Using a spike-in experiment to evaluate analysis of LC-MS data

BACKGROUND: Recent advances in liquid chromatography-mass spectrometry (LC-MS) technology have led to more effective approaches for measuring changes in peptide/protein abundances in biological samples. Label-free LC-MS methods have been used for extraction of quantitative information and for detection of differentially abundant peptides/proteins. However, difference detection by analysis of data derived from label-free LC-MS methods requires various preprocessing steps including filtering, baseline correction, peak detection, alignment, and normalization. Although several specialized tools have been developed to analyze LC-MS data, determining the most appropriate computational pipeline remains challenging partly due to lack of established gold standards. RESULTS: The work in this paper is an initial study to develop a simple model with "presence" or "absence" condition using spike-in experiments and to be able to identify these "true differences" using available software tools. In addition to the preprocessing pipelines, choosing appropriate statistical tests and determining critical values are important. We observe that individual statistical tests could lead to different results due to different assumptions and employed metrics. It is therefore preferable to incorporate several statistical tests for either exploration or confirmation purpose. CONCLUSIONS: The LC-MS data from our spike-in experiment can be used for developing and optimizing LC-MS data preprocessing algorithms and to evaluate workflows implemented in existing software tools. Our current work is a stepping stone towards optimizing LC-MS data acquisition and testing the accuracy and validity of computational tools for difference detection in future studies that will be focused on spiking peptides of diverse physicochemical properties in different concentrations to better represent biomarker discovery of differentially abundant peptides/proteins

Application of social vulnerability indicators to climate change for the southwest coastal areas of Taiwan

The impact of climate change on the coastal zones of Taiwan not only affects the marine environment, ecology, and human communities whose economies rely heavily on marine activities, but also the sustainable development of national economics. The southwest coast is known as the area most vulnerable to climate change; therefore, this study aims to develop indicators to assess social vulnerability in this area of Taiwan using the three dimensions of susceptibility, resistance, and resilience. The modified Delphi method was used to develop nine criteria and 26 indexes in the evaluation, and the analytic hierarchy process method was employed to evaluate the weight of each indicator based on the perspectives of experts collected through questionnaire surveys. The results provide important information pertaining to the vulnerability of the most susceptive regions, the lowest-resistance areas, and the least resilient townships on the southwest coast. The most socially vulnerable areas are plotted based on the present analysis. Experts can consider the vulnerability map provided here when developing adaptation policies. It should be kept in mind that improving the capacities of resistance and resilience is more important than reducing susceptibility in Taiwan

Protective effects of Scoparia dulcis L. extract on high glucose-induced injury in human retinal pigment epithelial cells

Diabetic retinopathy (DR) is a major cause of vision loss in diabetic patients. Hyperglycemia-induced oxidative stress and the accumulation of inflammatory factors result in blood-retinal barrier dysfunction and the pathogenesis of DR. Scoparia dulcis L. extract (SDE), a traditional Chinese medicine, has been recently recognized for its various pharmacological effects, including anti-diabetic, anti-hyperlipidemia, anti-inflammatory, and anti-oxidative activities. However, there is no relevant research on the protective effect of SDE in DR. In this study, we treated high glucose (50 mM) in human retinal epithelial cells (ARPE-19) with different concentrations of SDE and analyzed cell viability, apoptosis, and ROS production. Moreover, we analyzed the expression of Akt, Nrf2, catalase, and HO-1, which showed that SDE dose-dependently reduced ROS production and attenuated ARPE-19 cell apoptosis in a high-glucose environment. Briefly, we demonstrated that SDE exhibited an anti-oxidative and anti-inflammatory ability in protecting retinal cells from high-glucose (HG) treatment. Moreover, we also investigated the involvement of the Akt/Nrf2/HO-1 pathway in SDE-mediated protective effects. The results suggest SDE as a nutritional supplement that could benefit patients with DR

A Combined DNA-Affinic Molecule and N-Mustard Alkylating Agent Has an Anti-Cancer Effect and Induces Autophagy in Oral Cancer Cells

Although surgery or the combination of chemotherapy and radiation are reported to improve the quality of life and reduce symptoms in patients with oral cancer, the prognosis of oral cancer remains generally poor. DNA alkylating agents, such as N-mustard, play an important role in cancer drug development. BO-1051 is a new 9-anilinoacridine N-mustard-derivative anti-cancer drug that can effectively target a variety of cancer cell lines and inhibit tumorigenesis in vivo. However, the underlying mechanism of BO-1051-mediated tumor suppression remains undetermined. In the present study, BO-1051 suppressed cell viability with a low IC50 in oral cancer cells, but not in normal gingival fibroblasts. Cell cycle analysis revealed that the tumor suppression by BO-1051 was accompanied by cell cycle arrest and downregulation of stemness genes. The enhanced conversion of LC3-I to LC3-II and the formation of acidic vesicular organelles indicated that BO-1501 induced autophagy. The expression of checkpoint kinases was upregulated as demonstrated with Western blot analysis, showing that BO-1051 could induce DNA damage and participate in DNA repair mechanisms. Furthermore, BO-1051 treatment alone exhibited a moderate tumor suppressive effect against xenograft tumor growth in immunocompromised mice. Importantly, the combination of BO-1051 and radiation led to a potent inhibition on xenograft tumorigenesis. Collectively, our findings demonstrated that BO-1051 exhibited a cytotoxic effect via cell cycle arrest and the induction of autophagy. Thus, the combination of BO-1051 and radiotherapy may be a feasible therapeutic strategy against oral cancer in the future

Research and Development of Next Generation Air Cushion Smart System for Pressure Ulcer

本論文的目標是建立一套新世代壓瘡預防空氣坐墊之智慧型系統，目的在於解決壓瘡的問題。壓瘡是一個存在許久的議題，它不只會對病患本身及其家庭造成生理與經濟上的影響，對於護理人員乃至於整個醫療體系而言都是一大挑戰，可見壓瘡預防的重要性。 為了能夠設計出有效預防壓瘡的智慧型系統，本文首先針對壓瘡的形成做探討，並研究市面上相關的壓瘡預防產品以及研究文獻。再根據壓瘡的特性、成因及醫療上的對策，設計出可自動化降低壓瘡形成的個人化裝置。最後，從材料選擇、坐墊硬體設計及製作、氣囊熱壓成型製程、電路設計到最後軟硬體機電整合，製作出了壓瘡預防空氣坐墊之智慧型系統原型。此智慧型系統有三大功能：一、自動調整壓力，為乘坐者提供適當的臀部支撐及釋放壓力。二、調整乘坐者坐姿。三、量測乘坐者體重。 我們應用Arduino控制器來操控獨立氣囊陣列的充、放氣行為，藉由調整氣囊的壓力來釋放臀部的局部壓力，並且透過壓力感測器主動偵測每個獨立氣囊的壓力來作為自動充、放氣的依據，甚至能夠為乘坐者調整坐姿。同時，將偵測到的壓力求取平均值，換算為乘坐者的體重。The purpose of this thesis is to develop the Next Generational Air Cushion Smart System for preventing Pressure Ulcer. The goal is to solve the general problem of pressure ulcer for paralyzed patients, such as patients with spinal cord injury. Pressure ulcer is the issue that has existed for a long time. It not only brings physical and financial problems to patients themselves and their families, but also becomes a big challenge for medical professionals and even the whole medical system are affected. Thus, it is important to find a solution for preventing pressure ulcer. In order to design a smart system that can prevent pressure ulcer effectively, firstly, this study investigated the causes of pressure ulcer. We also summarized the previous researches and current commercialized products. Secondly, we identified a suitable solution based on the causes and disease process of pressure ulcer. Finally, we built a prototype of smart system based on an air cushion array for pressure ulcer. Material selection, fabrication of metal molds and thermoforming process, hardware implementation, circuit design as well as integration of hardware and software mechatronics were developed in this study. Three major functions of our smart system were developed and investigated, including: automatic adjustment of appropriate pressure, adjustment of the posture, and weight measurement. This study controls inflated and deflated actions of individual gasbag array to release the pressure of partial buttock by using an open access controller: Arduino. We defined inflated and deflated actions to adjust appropriate pressure and the posture by using pressure sensors to detect the pressure in each individual gasbag actively. At the same time, we calculate the average pressure and convert it into weight information

Dual-Domain Maximum Power Tracking for Multi-Input RF Energy Harvesting with a Reconfigurable Rectifier Array

This work proposes a dual-domain maximum power tracking (MPPT) technique for multiple-input RF energy harvesting systems. A differential rectifier array is used to implement 4-channel reconfigurable RF to DC power conversion, and an adjustable 4-bit capacitor array is designed to improve the impedance matching between the antennas and the rectifiers. Using the perturbation and observation (P&O) method, both arrays are adaptively configured in the background with the variations of the input energy and output loading. Experimental results show that the proposed circuit successfully tracks the maximum power points while harvesting RF energy, with the peak conversion efficiency of 49.06% when the input energy is −6 dBm. With the proposed dual-domain MPPT, the high efficiency range of the energy harvesting system is greatly extended to 21 dB (−21–0 dBm)