Lysophosphatidylcholine acyltransferase 1 is involved in the regulation of exosome secretion and uptake in colorectal cancer cells

Lysophosphatidylcholine acyltransferase 1 (LPCAT1) is a phospholipid acyltransferase that promotes phospholipid synthesis and plasma membrane reconstruction. Exosomes play an important role in tumor metastasis. The release and uptake of exosomes are key steps of their functions and depend on plasma membrane fusion and plasma membrane receptors, respectively. The purpose of this study was to explore whether LPCAT1-induced plasma membrane remodeling would change the secretion and uptake behavior of exosomes in tumor cells. We first confirmed the abnormally high expression of LPCAT1 in colorectal cancer cells by quantitative real-time PCR (qPCR) and Western blot analysis. Then, SW620 cells were used as exosome source cells, and SW480 cells were used as exosome receiver cells. Exosomes from SW620 cells could effectively promote the migration of SW480 cells. When LPCAT1 expression was reduced via siRNA knockdown in the source cells, the secretion of exosomes was downregulated, thus weakening the pro-migratory effects of exosomes on target cells. Conversely, when LPCAT1 was knocked down in target cells, the uptake of exosomes in target cells also decreased sharply. These results undoubtedly revealed that LPCAT1 is functionally associated with the release and internalization of exosomes in colorectal cancer cells and could affect the paracrine effects of exosomes, preliminarily extending the classical metabolic function of LPCAT1 to exosome-related pathways.     

Real-time single particle mass spectrometry: a historical review of a quarter century of the chemical analysis of aerosols

Real-time single particle mass spectrometry, or continuous aerosol mass spectrometry, was originally developed in the 1970s for the purpose of identifying the chemical composition of airborne particulate matter in real-time. Although this technique has continued to evolve throughout the following decades, the fundamental characteristic of this method remains the same, involving the continuous introduction of solid particle or liquid droplets directly into the ion source region of a mass spectrometer. Continuous sample introduction allows for the chemical analysis of single airborne particles in real-time. A number of mass analyzers have been employed in real-time single particle mass spectrometry. The original real-time single particle mass spectrometer used a magnetic sector mass analyzer. Quadrupole, double-focusing, and ion trap mass spectrometers have also been utilized. The majority of the current real-time single particle mass spectrometry techniques use time-of-flight mass spectrometry. In the literature, a variety of general names have been applied to real-time single particle mass spectrometry methods. These names include direct-inlet mass spectrometry, on-line laser microprobe mass spectrometry, particle analysis by mass spectrometry, particle beam mass spectrometry, and rapid-single particle mass spectrometry. This review covers real-time single particle mass spectrometry techniques that were developed from 1973 through 1998, specifically for analyzing airborne particulate matter, including environmental aerosols, biological aerosols, and clean-room aerosols. Because the majority of the historical and current real-time single particle mass spectrometers have been employed for atmospheric aerosols, this topic is the primary focus of this review. This review does not include on-line mass spectrometry methods that are employed as a detector for other instrumental methods, such as liquid chromatography.     

Urinary exosomes and proteomics

A number of highly abundant proteins in urine have been identified through proteomics approaches, and some have been considered as disease-biomarker candidates. These molecules might be clinically useful in diagnosis of various diseases. However, none has proven to be specifically indicative of perturbations of cellular processes in cells associated with urogenital diseases. Exosomes could be released into urine which flows through the kidney, ureter, bladder and urethra, with a process of filtration and reabsorption. Urinary exosomes have been recently suggested as alternative materials that offer new opportunities to identify useful biomarkers, because these exosomes secreted from epithelial cells lining the urinary track might reflect the cellular processes associated with the pathogenesis of diseases in their donor cells. Proteomic analysis of such urinary exosomes assists the search of urinary biomarkers reflecting pathogenesis of various diseases and also helps understanding the function of urinary exosomes in urinary systems. Thus, it has been recently suggested that urinary exosomes are one of the most valuable targets for biomarker development and to understand pathophysiology of relevant diseases.     

Microorganism characterization by single particle mass spectrometry

In recent years a major effort by several groups has been undertaken to identify bacteria by mass spectrometry at the single cell level. The intent of this review is to highlight the recent progress made in the application of single particle mass spectrometry to the analysis of microorganisms. A large portion of the review highlights improvements in the ionization and mass analysis of bio-aerosols, or particles that contain biologically relevant molecules such as peptides or proteins. While these are not direct applications to bacteria, the results have been central to a progression toward single cell mass spectrometry. Developments in single particle matrix-assisted laser desorption/ionization (MALDI) are summarized. Recent applications of aerosol laser desorption/ionization (LDI) to the analysis of single microorganisms are highlighted. Successful applications of off-line and on-the-fly aerosol MALDI to microorganism detection are discussed. Limitations to current approaches and necessary future achievements are also addressed.     

Mesenchymal stem cell-derived exosome: The likely game-changer in stem cell research

Stem cell research is a promising area of transplantation and regenerative medicine with tremendous potential for improving the clinical treatment and diagnostic options across a variety of conditions and enhancing understanding of human development. Over the past few decades, mesenchymal stem cell (MSCs) studies have exponentially increased with a promising outcome. However, regardless of the huge investment and the research attention given to stem cell research, FDA approval for clinical use is still lacking. Amid the challenges confronting stem cell research as a cell-based product, there appears to be evidence of superior effect and heightened potential success in its expressed vesicles, exosomes, as cell-free products. In addition to their highly desirable intrinsic biologically unique structural, compositional, and morphological characteristics, as well as predominant physiochemical stability and biocompatibility properties, exosomes can also be altered to enhance their therapeutic capability or diagnostic imaging potential via physical, chemical, and biological modification approaches. More importantly, the powerful therapeutic potential and superior biological functions of exosomes, particularly, regarding engineered exosomes as cell-free products, and their utilization in a new generation of nanomedicine treatment, vaccination, and diagnosis platforms, brings hope of a change in the near future. This viewpoint discusses the trend of stem cell research and why stem cell-derived exosomes could be the game-changer.     

Immunoregulatory effects of human amniotic mesenchymal stem cells and their exosomes on human peripheral blood mononuclear cells

Background: The immunomodulatory effects of mesenchymal stem cells (MSCs) and their exosomes have been receiving increasing attention. This study investigated the immunoregulatory effects of human amniotic mesenchymal stem cells (hAMSCs) and their exosomes on phytohemagglutinin (PHA)-induced peripheral blood mononuclear cells (PBMCs). Methods: The hAMSCs used in the experiment were identified by light microscopy and flow cytometry, and the differentiation ability of the cells was determined by Oil Red O and Alizarin Red staining. The expressions of transforming growth factor (TGF)-β, indoleamine 2,3-dioxygenase (IDO), cyclooxygenase-2 (COX-2), hepatocyte growth factor (HGF), and interleukin (IL)-6 were detected by quantitative real-time polymerase chain reaction and western blotting. PBMCs, hAMSCs, and their exosomes were collected for in vitro group culture. Then the immunoregulatory ability of hAMSCs and their exosomes were analyzed by flow cytometry and Enzyme-linked immunosorbent assay. Results: The hAMSCs and exosomes were successfully extracted from the human amniotic membrane. TGF-β, IDO, COX-2, HGF, and IL-6 were significantly expressed in hAMSCs. In vitro co-culture showed that hAMSCs promoted the proliferation of Th2 cells in PHA-induced PBMCs, while hAMSCs and exosomes inhibited the secretion of TNF-α in PHA-induced PBMCs, and promoted the secretion of IL-4 and IL-10, and hAMSCs had more significant effects than exosomes. Conclusions: hAMSCs or exosomes could exert immunoregulatory effects on PHA-induced PBMCs by affecting Th2 cell proliferation and cytokine secretion.     

Anesthesia gas monitoring: central system or stand-alone?

Two approaches to intraoperative anesthetic gas monitoring exist today. Central, mass-spectrometer-based systems share cost and analyzer time among several remote locations. Stand-alone monitors are usually infrared analyzers and are dedicated to a single monitoring location. The advantages and disadvantages of each are due primarily to the shared versus dedicated approaches. Dedicated analyzers, while limited somewhat by infrared technology, offer uninterrupted, real-time analysis of anesthetic and respiratory gases. Central systems offer excellent monitoring but are limited to periodic updates of each monitored location. This article attempts a complete analysis of these and other factors affecting the use, reliability, and cost effectiveness of these two approaches to anesthesia gas monitoring.     

Mirror Langmuir probe: a technique for real-time measurement of magnetized plasma conditions using a single Langmuir electrode

A new method for the real-time evaluation of the conditions in a magnetized plasma is described. The technique employs an electronic "mirror Langmuir probe" (MLP), constructed from bipolar rf transistors and associated high-bandwidth electronics. Utilizing a three-state bias wave form and active feedback control, the mirror probe's I-V characteristic is continuously adjusted to be a scaled replica of the "actual" Langmuir electrode immersed in a plasma. Real-time high-bandwidth measurements of the plasma's electron temperature, ion saturation current, and floating potential can thereby be obtained using only a single electrode. Initial tests of a prototype MLP system are reported, proving the concept. Fast-switching metal-oxide-semiconductor field-effect transistors produce the required three-state voltage bias wave form, completing a full cycle in under 1 mus. Real-time outputs of electron temperature, ion saturation current, and floating potential are demonstrated, which accurately track an independent computation of these values from digitally stored I-V characteristics. The MLP technique represents a significant improvement over existing real-time methods, eliminating the need for multiple electrodes and sampling all three plasma parameters at a single spatial location.     

Structural crack detection without updated baseline model by single and multiobjective optimization

Identification, localization and quantification of structural damage can be performed through a model-updating procedure. Model-updating methods require a baseline finite element (FE) model of the undamaged structure, which imposes a restriction on their applicability and can become very problematic especially for large and complex civil structures. Modeling errors in the baseline model whose effects exceed the modal sensitivity to damage are critical and make an accurate estimation of damage impossible. This paper presents an identification algorithm using modal data for assessing structural damage that is based on FE-updating procedures and takes modeling error into account. To overcome its influence, differences of mode shapes and frequencies before and after damage for both numerical model and experimental measurements are used instead of the mode shapes and frequencies themselves. To formulate the objective function, two different approaches have been considered taking into account how these differences are grouped: a single-objective approach and a multiobjective approach. The effectiveness of both approaches is verified against numerical and experimental results.     

A robust single row facility layout problem with fuzzy random variables

The facility layout problem is the optimal arrangement of facilities in the plant area. Based on layout configurations, there are several types of the facility layout problem. The single row facility layout problem (SRFLP) is one them in which facilities have to be placed along a line. Although there are exact approaches, based on the integer programming model for solving SRFLP, a huge number of variables and constraints should be used in this model. This paper presents a new exact method to SRFLP based on a new class of variables and an extended branch and bound method (B&B). First, the SRFLP is formulated by new decision variables. To solve it, a new branching scheme for B&B algorithm is presented. Subsequently, we introduce a fuzzy robust single row facility layout problem (FRSRFLP) and solve it by a real expected value method and a fuzzy stochastic chance-constrained programming based on possibility and necessity measures together with an extended B&B method. Furthermore, the proposed methods are applied for solving some benchmark problems to show their efficiency.     

两栖仿生机器蟹单足运动控制系统

建立了两栖仿生机器蟹的单足运动控制系统。系统采用了基于TMS320LF2407芯片的硬件结构。在VC6．0中编制了上位控制程序，用多项式的方法实现了足尖路径的实时规划。采用了Bang—Bang控制和PID调节相结合的双模控制算法实现位置伺服控制。     

Raloxifene-loaded and aptamer-bonded exosomes induce autophagic and apoptotic death in HeLa cells by enhancing the lysosomotropic effect

Background: Raloxifene, a selective estrogen receptor modulator, is also known to be a lysosomotropic agent. The bioavailability of raloxifene is around 2% due to extensive hepatic transport. Exosomes are nanosized vesicles that are naturally released from cells. Method: In this study, exosomes released from HeLa cervical cancer cells were loaded with raloxifene to increase its bioavailability, and an aptamer was attached to the exosome membrane for targeting only HeLa cells. Characterization of exosomes isolated from HeLa cells was performed by transmission electron microscopy, zeta sizer, and western blotting. In addition, the cytotoxic, apoptotic, autophagic, and lysosomotropic effects of the prepared Exo-Apt-Ral formulation on HeLa cervical cancer cells were investigated. Results: According to zeta analysis, the sizes of the empty exosome and Exo-Apt-Ral formulation were measured as 66 ± 12 and 120 ± 21 nm, respectively. There was a rise in the lysosomal permeability of HeLa cells after the Exo-Apt-Ral application. In addition, both apoptotic and autophagic death mechanisms were triggered in HeLa cells after the Exo-Apt-Ral application. Conclusion: This study showed that raloxifene functionalized by loading into aptamer-bound exosomes can be a new targeted drug carrier system for cervical cancer.     

Implementation of adaptive indoor comfort temperature control via embedded system for air-conditioning unit

Environmental control strategy via computerized implementation is one of the most efficient approaches to integrate new advanced knowledge in research of human thermal comfort to a mechanical air-conditioning unit. Recently, a new conceptual development in designing air-conditioning systems has indicated that the indoor comfort temperature strongly depends upon changes of the outdoor air temperature rather than to be a conventional fixed temperature set-point. The explanation is due to occupants’ adaptability of thermal comfort to a dynamic environment in terms of their clothing and/or activities while the outdoor temperature can be explicitly used as an ultimate indicator of such changes to empirical function of the indoor comfort temperature. In this paper, the first prototype embedded system is developed to emulate such an adaptive algorithm to numerically determine an indoor comfort temperature for a real-time control in an air-conditioning system. From a theoretical point of view, an adaptive comfort model together with grey prediction model is presented for exploring a practical application of a comfort temperature-based control for a single air-conditioned space, so as to show the viability of the proposed methodology by simulated results. The field studies by interview survey of satisfaction on thermal comfort within an air-conditioned reading room of a library confirm the viability of the proposed real-time computerized implementation of adaptive indoor comfort temperature via the embedded system for a conventional air-conditioning unit in practical uses.     

Mesenchymal stem cells,secretome and biomaterials in <i>in-vivo</i> animal models: Regenerative medicine application in cutaneous wound healing

The treatment of nonhealing and chronic cutaneous wounds still needs a clinical advancement to be effective. Both mesenchymal stem cells (MSCs), obtained from different sources, and their secretome derived thereof (especially exosomes) can activate signaling pathways related to promotion of cell migration, vascularization, collagen deposition, and inflammatory response demonstrating prohealing, angiogenetic and anti-scarring capacities. On the other hand, biodegradable biomimetic scaffolds can facilitate endogenous cell attachment and proliferation as well as extracellular matrix production. In this Review, we revise the complex composites made by biomimetic scaffolds, mainly hydrogels, and MSC-derived exosomes constructed for cutaneous wound healing. Studies demonstrate that there exists a synergistic action of scaffolds with encapsulated exosomes, displaying a sustained release profiles to facilitate longlasting healing effects. It can be envisioned that dressings made by biomimetic hydrogels and MSC-derived exosomes will be clinically applied in the near future for the effective treatment of nonhealing and chronic wounds.     

基于FPGA的单粒子气溶胶质谱时序控制系统

在单粒子气溶胶的粒径分布和化学组分实时分析的激光质谱系统中，应用现场可编程门阵列技术，讨论了高速数字电路中的精确定时问题，并研制了一套测量系统，对实际大气中气溶胶粒子进行粒径大小的统计分布和质谱的测定。     

Ab-initio primitive cell parameters from single convergent-beam electron diffraction patterns: a converse route to the identification of microcrystals with electrons.

A new method for the ab initio derivation of Buerger-reduced primitive cell parameters from coordinate measurements of spots on single convergent-beam electron diffraction (CBED) patterns is described, which does not involve trial-and-error. The pattern can be taken along any zone axis, and misorientations of the crystallite by as much as a few degrees are taken into account without loss of accuracy. This derivation of cell parameters by least-squares analysis of the measurements has been automated in a program called NRCBED. Present accuracy is about 1% on lengths and 2 degrees on angles, but could be significantly improved by modelling projector lens aberrations, or by using a microscope without a projector lens. With present technology, it is possible to obtain a CBED pattern and a semi-quantitative energy-dispersive X-ray (EDX) analysis simultaneously from a single microcrystal a few hundred Angstr?ms across. It becomes therefore possible to identify the material of the crystal on a single CBED pattern: a cell parameter database for known compounds is searched with the primitive cell parameters obtained in the above way, and with a mask describing the EDX results qualitatively. Feasibility is demonstrated on a crystallite of CeO2 500 Angstr?ms across. With this new approach, trial-and-error should disappear from the solution of other long-standing problems: interpretation of X-ray powder patterns for new compounds in the presence of impurity lines, or in the case of multiple phases should become straight-forward.     

基于SIMULINK-S函数的联合站脱水单神经元PID仿真

集输联合站的油水分离是保证产出原油质量的关键工艺过程。该文在对油水分离沉降过程动态特性深入研究的基础之上,给出了其数学模型。单神经元PID控制具有自学习和自适应能力,在一定程度上解决了传统PID调节器不易在线实时整定参数的不足,提高了控制器对系统和环境变化的适应能力。 SIMULINK中可用S-Function方便灵活地构建各种自定义仿真模型。该文使用SIMULINK中的S-Function Builder模块以快速构建单神经元PID控制模块,并在SIMU-LINK中对单神经元PID控制方案进行了仿真研究,仿真结果表明该算法可获得更好的调节质量。     

单螺杆压缩机的新进展

从基础理论、机床、刀具和技术创新等角度，指出了提高产品质量的途径。顺德正力精工综合运用这些技术，提高了单螺杆压缩机在高压下工作时的效率，延长了星轮的寿命，使产品达到国际先进水平。     

Human following of a mobile service robot with single laser range finder

The human following becomes one of the significant procedure in human-friendly navigation of mobile robots.Many potential applications of human-following technology are developed lately.This paper sugg...     

基于协商的Multi-Agent生产计划与调度系统

目前企业使用的ERP系统中由于计划与能力计算的分离以及调度信息不能及时反馈 ,已很难适应敏捷制造的需要。Agent技术是进行分布式制造系统建模的一种主要方法之一。工作中心是各种生产能力单元的通称 ,也是发生加工成本的实体 ,各工作中心Agent之间通过协商与协作 ,形成一个基于能力与成本的Multi Agent集成生产计划与调度系统 ,使企业具有实时应变性。