基于智能手机的生物传感器及其在即时检测中的应用进展

日常健康管理对即时检测(POCT)的需求不断增加,而生物传感器作为一类高灵敏、微型化的生物标志物检测仪器,在POCT中具有巨大的应用潜能。近年来,智能手机的普及和生物传感器技术的进步促进了基于智能手机的生物传感器的发展,这类生物传感器具有便携、快速、低成本、易操作等优点,可以满足POCT对生物传感器日益严格的要求。从基于智能手机的光学生物传感器技术(包括显微镜成像技术、比色技术、荧光技术、生物发光技术和表面等离子共振SPR技术)和电化学生物传感器技术(包括电流法、电位法以及阻抗法)两个方面,介绍了基于智能手机的生物传感器及其在POCT研究中的应用,并关注了其在航天医学领域的应用潜力。     

基于CRISPR均相电化学生物传感器检测SARS-CoV-2和HIV-1方法的建立

目的 建立基于CRISPR-Cas13a系统的均相电化学生物传感器并用于病原微生物的核酸检测。方法通过逆转录-重组酶介导链替换核酸扩增技术（RT-RAA）对目标核酸进行扩增,经过体外转录后,激活Cas13a蛋白高效切割单链RNA的活性并对标记有亚甲基蓝（MB）的报告RNA进行剪切,构建CRISPR均相电化学生物传感器;通过遴选报告RNA上寡核苷酸的长度优化该传感器;利用该传感器检测新型冠状病毒（SARS-CoV-2）RNA和Ⅰ型人类免疫缺陷病毒（HIV-1）RNA,并对其检测性能进行评价。结果 建立了一种基于CRISPR-Cas13a系统和RT-RAA等温扩增技术的均相电化学生物传感器,利该方法使用相对应的扩增引物和CRISPR RNA(crRNA)后能稳定检测出低至102拷贝/μl的SARS-CoV-2 RNA和HIV-1 RNA,并与其他多种病原体未发生交叉反应。结论该基于CRISPR-Cas13a系统的均相电化学生物传感器具有制备简单、灵敏度高、特异性好和通用性强等优点,为病原微生物的现场快速检测提供了新的可行方案。     

肝癌循环肿瘤细胞研究进展

循环肿瘤细胞（CTC）作为一种可靠的生物标志物,具有无创、检测特异性高等优点。近年来,CTC检测已经广泛用于肝癌诊断,包括肝癌的早期诊断、复发诊断及预后判断等方面。综述CTC转移机制及转移特征、检测技术（包括物理检测和生物检测）的更新及综合应用,结合其在肝癌诊断中的相关研究进展,并对其应用前景进行展望。     

DNA电化学生物传感器检测病原微生物的应用研究进展

病原微生物的快速检测对于疫情防控具有重要意义。与传统检测方法相比,DNA电化学生物传感器在检测度、灵敏度、检测成本与便携性等方面有诸多优势。该文综述了DNA电化学生物传感器的工作原理及其在病原体检测中的应用,重点阐述了核酸四面体结构探针和新型纳米材料在DNA电化学生物传感器中的最新进展,以及DNA电化学生物传感器检测技术在病原体现场快速检测中面临的挑战和发展趋势。     

饮用水中总大肠菌群检测方法的研究进展

为保证饮用水的安全，寻找更快速、更灵敏、更特异的饮用水检测方法。本研究就饮用水中总大肠菌群检测方法的研究进展做一综述。总大肠菌群检测已经被广泛地应用在饮用水质的监测上，用于总大肠菌群检测的传统方法包括多管发酵法（MTF）和总大肠菌群滤膜法（MF），这两种方法都需要专门的培养基和孵育条件，都具有局限性。基于特异酶活性的检测方法提高了检测的速度和灵敏度，是一种很有潜力的替代传统方法的技术。近年来多种基于生物大分子的方法用于检测大肠菌群发展迅速，具有很高的灵敏度和特异性，但也存在某些缺陷。目前尚缺乏一种世界公认的饮用水总大肠菌群检测的标准方法。     

床旁检验在急性冠脉综合征患者中的应用探讨

目的探究床旁检验（POCT）在急性冠脉综合征患者中的应用价值。方法选取2011年3月～2013年3月心内科收治的急性冠脉综合征患者108例，作为研究对象。所有的患者均行床旁检验（POCT）及检验科送捡，出院前对患者各项检查进行综合评估确定诊断。依据检验的方式不同分为床旁检验纽和检验科送检纽，比较两中检验方式的检验时间、检验结果及与最终检查结果符合度情况。综合以上数据探讨POCT在急性冠脉综合征患者中的应用价值。结果床旁检验组检验时间显著短于检验科送检组（P〈0．05），检测结果（肌红蛋白、肌钙蛋白Ⅰ、肌酸激酶同工酶）在这两种检验方式中病无差异性（P〉0．05）；在急性冠脉综合征确诊的患者中，两种检验方式检验符合度情况也无差异性（P〉0．05）。结论床旁检验和检验科抽血送检均可有助于急性冠脉综合征的早期诊断，诊断结果无差异性，但是床旁检验能缩短检验结果时间，为急诊治疗争取更佳时间。     

即时检验血糖仪检测指尖血及静脉全血血糖的临床分析

目的：探究即时检验血糖仪（ POCT ）检测指尖血及静脉全血血糖的临床效果。方法选取收治的18例糖尿病患者，作为研究的对象。取指尖血、静脉血经POCT实行血糖检测，并通过生化分析仪对患者的血浆葡萄糖水平进行检测，比较两个不同部位检测结果。结果指尖血、静脉全血通过POCT检测血糖的结果，存在一定的负偏倚，偏倚的范围在－1．52％～－14．1％的范围，且在20％之内。静脉全血测定结果的偏倚，明显高于指尖血测定的结果，差异具有统计学意义，P＜0．05。结论指尖血、静脉全血血糖经POCT检测，可满足临床血糖水平的检测需求，且指尖血检测的结果与生化分析仪检测血浆葡萄糖的水平更加相近。     

基于表面等离子体共振原理的核酸检测技术

目的 建立基于表面等离子体共振(surface plasmon resonance,SPR)生物传感器的核酸检测技术,为实时、在线检测航天微生物奠定技术基础.方法 应用本实验室建立的便携式生物分子在线分析系统(portable online bio-molecules analyzer,POBA),在传感器表面固化探针分子,对溶液中的靶序列进行杂交检测,研究该检测方法的灵敏度、特异性及可重复性等.结果 实验中建立的核酸检测方法能够实现对靶序列的实时检测,检测下限达2.3 nmol/L,进行9次杂交检测的变异系数为3.5%,重复进行30次检测的变异系数为14.7%.结论 本实验建立的核酸检测方法,具有灵敏度高、特异性强、可重复性好等优点,SPR传感器技术在核酸杂交检测工作中有着广阔的应用前景.     

POCT发展现状及临床应用

POCT（point of care testing,POCT）作为临床检验领域新出现的一种检验手段,正日益受到人们的重视。最近美国国家临床生化科学院（NACB）在其制定的“POCT循证文件”草案中,将POCT定义为：“在接近病人治疗处,由未接受临床实验室学科训练的临床人员或者病人（自我检测）进行的临床检验,是在传统、核心或中心实验室以外进行的一切检验”。     

合成生物学技术在地雷检测中的应用

近年来,随着合成生物学技术的发展,许多基于合成生物学的生物传感器检测方法应运而生。其中基于合成生物学的地雷检测技术能够提供较高的检测特异性,并且使用安全,价格低廉。本文主要介绍一些利用合成生物学技术的方法,通过检测地雷泄漏物24,,6-三硝基甲苯（TNT）来实现地雷的生物检测。     

Massive parallel sequencing applied to the molecular autopsy in sudden cardiac death in the young

Sudden cardiac death in the young is a very traumatic event that occurs often in apparently healthy individuals without an explainable cause of death after a comprehensive medico-legal investigation. Knowledge about the pathologies with a risk of sudden death is increasingly showing a greater underlying genetic heterogeneity, which provides one of the main handicaps for molecular autopsy. On the other hand the enormous technological advances in sequencing technologies, allow us to analyse as many genes as we want at a cost increasingly reduced. The sum of these two factors (increased knowledge of genetics and available technologies) allow us to make an individualized study of the causes of sudden cardiac death in young adults, through massive sequencing of all potential genes involved in the process. We define this approach as massive genomic autopsy, and with this review we will try to explain the possible scenarios and methods available for its implementation.     

Reliability and validity of a smartphone-based assessment of gait parameters across walking speed and smartphone locations: Body,bag, belt,hand, and pocket

The assessment of spatiotemporal gait parameters is a useful clinical indicator of health status. Unfortunately, most assessment tools require controlled laboratory environments which can be expensive and time consuming. As smartphones with embedded sensors are becoming ubiquitous, this technology can provide a cost-effective, easily deployable method for assessing gait. Therefore, the purpose of this study was to assess the reliability and validity of a smartphone-based accelerometer in quantifying spatiotemporal gait parameters when attached to the body or in a bag, belt, hand, and pocket. Thirty-four healthy adults were asked to walk at self-selected comfortable, slow, and fast speeds over a 10-m walkway while carrying a smartphone. Step length, step time, gait velocity, and cadence were computed from smartphone-based accelerometers and validated with GAITRite. Across all walking speeds, smartphone data had excellent reliability (ICC_2,1 ≥ 0.90) for the body and belt locations, with bag, hand, and pocket locations having good to excellent reliability (ICC_2,1 ≥ 0.69). Correlations between the smartphone-based and GAITRite-based systems were very high for the body (r = 0.89, 0.98, 0.96, and 0.87 for step length, step time, gait velocity, and cadence, respectively). Similarly, Bland-Altman analysis demonstrated that the bias approached zero, particularly in the body, bag, and belt conditions under comfortable and fast speeds. Thus, smartphone-based assessments of gait are most valid when placed on the body, in a bag, or on a belt. The use of a smartphone to assess gait can provide relevant data to clinicians without encumbering the user and allow for data collection in the free-living environment.     

Biomedical devices in meniscal repair

Preservation of the menisci is increasingly emphasized in orthopedic care of the knee. Techniques are rapidly emerging that allow easier accomplishment of this goal. In particular, the development of all-inside arthroscopic meniscal repair devices has facilitated more ready repair. A number of laboratory and clinical studies have examined these devices and comparisons with more traditional techniques have been made. Numerous reports of potential complications from these new technologies have also been described in the literature. This review covers the current options for treatment of meniscal repair, laboratory and clinical data, and also potential complications.     

mVEGAS – mobile smartphone-based spatiotemporal gait analysis in healthy and ataxic gait disorders

BackgroundQuantitative gait assessment is increasingly applied in fall risk stratification, diagnosis, and disease monitoring of neuro-geriatric gait disorders. Its broad application, however, demands for low-cost and mobile solutions that facilitate high-quality assessment outside laboratory settings. The aim of this study was to present and evaluate the concurrent validity of a mobile and low-cost gait assessment tool (mVEGAS) that combines body-fixed inertial sensors and a smartphone-based video capture for spatiotemporal identification of gait sequences.MethodsInitially, we examined potential interferences of wearing mVEGAS with walking performance in a cohort of 20 young healthy individuals (31.1 ± 10.1 years; 8 females). Subsequently, we assessed the concurrent validity of mVEGAS as compared to a pressure-sensitive gait carpet (GAITRite) in a cohort of 26 healthy individuals (55.8 ± 14.3 years; 10 females) and 26 patients (55.7 ± 14.0; 14 females) with moderate to severe degrees of cerebellar gait ataxia. All participants were instructed to walk at preferred, slow, and fast walking speed and standard average and variability gait measures including velocity, stride length, stride time, base of support, swing and double support phase were examined for agreement between the two systems by absolute error and intraclass correlation coefficients (ICC).ResultsWearing mVEGAS did only marginally interfere with normal walking behavior. mVEGAS-derived average and variability gait measures exhibited good to excellent concurrent validity in healthy individuals (ICCs ranging between 0.645 and 1.000) and patients with gait ataxia (ICCs ranging between 0.788 and 1.000)SignificancemVEGAS may facilitate high-quality and long-term gait monitoring in different non-specialized environments such as medical practices, nursing homes or community centers.     

Potential role of imaging for assessing acute pancreatitis-induced acute kidney injury

Acute kidney injury (AKI) is a common complication of acute pancreatitis (AP) that is associated with increased mortality. Conventional assessment of AKI is based on changes in serum creatinine concentration and urinary output. However, these examinations have limited accuracy and sensitivity for the diagnosis of early-stage AKI. This review summarizes current evidence on the use of advanced imaging approaches and artificial intelligence (AI) for the early prediction and diagnosis of AKI in patients with AP. CT scores, CT post-processing technology, Doppler ultrasound, and AI technology provide increasingly valuable information for the diagnosis of AP-induced AKI. Magnetic resonance imaging (MRI) also has potential for the evaluation of AP-induced AKI. For the accurate diagnosis of early-stage AP-induced AKI, more studies are needed that use these new techniques and that use AI in combination with advanced imaging technologies.     

Emerging methods in economic modeling of imaging costs and outcomes a short report on discrete event simulation

RATIONALE AND OBJECTIVES: This short report provides a non-technical overview of one emerging modeling technique, discrete event simulation (DES). METHODS: A selective review of the literature that has applied DES methods to evaluate imaging technologies. RESULTS: Mathematical models to evaluate the likely costs and outcomes of health technologies have become increasingly accepted. Increasing experience has also brought a mounting awareness of the limitations of conventional modeling techniques such as decision trees and Markov processes. Patient-level simulation, including DES, may provide a more flexible approach to modeling for economic evaluation of health technologies. CONCLUSIONS: The strengths of DES suggest that it may have an increasingly important role in the future modeling of annual screening programs, diagnosis, and treatment of chronic recurrent disease and modeling the utilization of imaging equipment.     

U-turn speed is a valid and reliable smartphone-based measure of multiple sclerosis-related gait and balance impairment

BackgroundPeople living with multiple sclerosis (MS) experience impairments in gait and mobility, that are not fully captured with manually timed walking tests or rating scales administered during periodic clinical visits. We have developed a smartphone-based assessment of ambulation performance, the 5 U-Turn Test (5UTT), a quantitative self-administered test of U-turn ability while walking, for people with MS (PwMS).Research questionWhat is the test-retest reliability and concurrent validity of U-turn speed, an unsupervised self-assessment of gait and balance impairment, measured using a body-worn smartphone during the 5UTT?Methods76 PwMS and 25 healthy controls (HCs) participated in a cross-sectional non-randomised interventional feasibility study. The 5UTT was self-administered daily and the median U-turn speed, measured during a 14-day session, was compared against existing validated in-clinic measures of MS-related disability.ResultsU-turn speed, measured during a 14-day session from the 5UTT, demonstrated good-to-excellent test-retest reliability in PwMS alone and combined with HCs (intraclass correlation coefficient [ICC] = 0.87 [95 % CI: 0.80–0.92]) and moderate-to-excellent reliability in HCs alone (ICC = 0.88 [95 % CI: 0.69–0.96]). U-turn speed was significantly correlated with in-clinic measures of walking speed, physical fatigue, ambulation impairment, overall MS-related disability and patients’ self-perception of quality of life, at baseline, Week 12 and Week 24. The minimal detectable change of the U-turn speed from the 5UTT was low (19.42 %) in PwMS and indicates a good precision of this measurement tool when compared with conventional in-clinic measures of walking performance.SignificanceThe frequent self-assessment of turn speed, as an outcome measure from a smartphone-based U-turn test, may represent an ecologically valid digital solution to remotely and reliably monitor gait and balance impairment in a home environment during MS clinical trials and practice.     

Radiation-induced temporary hair loss as a radiation damage only occurring in patients who had the combination of MDCT and DSA

As imaging technologies become increasingly advanced, it is possible to obtain detailed morphological information as well as functional imaging data. In some imaging technologies, the radiation dose increases with the ability to obtain better images or more detailed information. We encountered three cases of temporary bandage-shaped hair loss, which was caused by perfusion studies of the head by multi-detector row computed tomography (MDCT) for evaluation of cerebral blood flow in patients with vascular disorders. In all three patients with temporary hair loss, two angiographies of the head had been performed in the period of serial CT examinations. This suggested the possibility that radiation exposure from angiography performed in serial examinations, combined with the perfusion studies of the head with MDCT, played an important role in this temporary, bandage-shaped hair loss. Radiologists should be aware that a cumulative or multiplier effect of radiation exposure from multiple diagnostic techniques may result in hair loss and other types of radiation complications.     

ACR Appropriateness Criteria Indeterminate Renal Mass

Renal masses are increasingly detected in asymptomatic individuals as incidental findings. An indeterminate renal mass is one that cannot be diagnosed confidently as benign or malignant at the time it is discovered. CT, ultrasonography, and MRI of renal masses with fast-scan techniques and intravenous (IV) contrast are the mainstays of evaluation. Dual-energy CT, contrast-enhanced ultrasonography, PET/CT, and percutaneous biopsy are all technologies that are gaining traction in the characterization of the indeterminate renal mass. In cases in which IV contrast cannot be used, whether because of IV contrast allergy or renal insufficiency, renal mass classification with CT is markedly limited. In the absence of IV contrast, ultrasonography, MRI, and biopsy have some advantages. Owing to the low malignant and metastatic potential of small renal cell carcinomas (≤4 cm in diameter), active surveillance is additionally emerging as a diagnostic strategy for patients who have high surgical risk or limited life expectancy.The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 3 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and application by the panel of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.