Cut-off Values of Diagnostic Indices to Detect Iron Deficiency in Chinese Breast-fed Infants

Iron deficiency anemia is one of the most prevalent nutritional deficiency worldwide. The commonly used cut-off values for identifying iron deficiency are extrapolated from older children and may not be suitable for infants. Therefore, our study aimed to establish appropriate cut-off values for the evaluation of iron status in Chinese infants. Pregnant women who delivered at 〉37 gestational weeks with normal iron status were recruited. Later, infants with normal birth weight and who were breastfed in the first 4 months were selected. Blood samples were collected to assess hemoglobin, serum ferritin, soluble transferrin receptor, mean corpuscular volume and free erythrocyte protoporphyrin. Cut-offs of all iron indices were determined as the limit of 95% confidence interval.

Evaluation of an Innovative Diagnostic Method for Detection of Antibodies and Antigens

Reports manifest a continuing need for the development of rapid and on-site (point of care) assays. Current diagnostic methods commonly used for detection of antibodies and antigens have significant limitations. Scientists at Micro Detect, Inc. have developed an innovative diagnostic device (method) that can be utilized broadly for antibody/antigen interactions including diagnostic assays in the medical, veterinary and food industries. The developed device can be utilized for the detection of antibodies against a single antigen or vice versa. It can also be tailored for specific panels that detect antigens or antibodies for diverse infectious agents, proteins, hormones, tumor markers, autoimmune markers, and allergens. Additionally, it can also be used for detection of toxins, antitoxins, nucleic acids, enzymes, drugs, etc. in both humans and animals. Specimens used in different formats of the device can be tears, saliva, whole blood, serum, plasma, urine, stool, and other bodily discharges. The good intra and inter precisions and acceptable linearity of the device support reliable use of the device. The CV of the device is 1.9% - 2.2%. Likewise, the performance of the device using 92 confirmed negative and positive specimens via a typical assay showed 100% sensitivity, 80% specificity, 96.8% efficacy, 80% positive predictive value, and 100% negative predictive value. The results of our feasibility study suggest reliable utility of a device for rapid, easy-to-use, inexpensive, and on-site (point of care) diagnostic assays. This presents a potential breakthrough in diagnostic methodologies that can be integrated into modern medicine and food industries.

Relation of predictive value to sensitivity and specificity of a diagnostic test

This paper discusses how the positive and negative predictive values vary withcontrary variations of sensitivity and specificity at a certain disease prevalence.Let thesensitiviy be Se and the specificity be Sp at the initial cutoff point,correspondingly Se’and Sp’ at a new cutoff point:A=Se’/Se:B-(1-Sp’)/(1-Sp):C=Sp’/Sp;D=(I-Se’)/(I-Se).Moving the cutoff point from the initial point to the new point,if the contrary variationsof the sensitivity and specificity satisfy the inequality A】B,then the positive predictivevalue increases,otherwise it decreases or remains unchanged.If the variations satisfy theinequality C】D,then the negative prcdictive value increases,otherwise it decreasses or re-mains unchanged.

Determination of the diagnostic value of the resazurin reduction assay for evaluating boar semen by receiver operating characteristic analysis

Aim： To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods： The accuracy of the spectrophotometric application of the resazurin reduction assay was assessed using receiver operating characteristic （ROC） analysis. Results： Areas under ROC curves （AUC） for motile sperm concentration and sperm index （SI） （sperm concentration multiplied by the square root of percentage sperm motility multiplied by the percentage normal sperm morphology） were 0.922. The best discrimination between poor and good semen samples according to the SI was achieved at a cut-off point of A610 = 0.209, where high sensitivity （94.1%） and specificity （91.7%） were calculated. The assay was less accurate when motile sperm concentration was used as the criterion value, yielding sensitivity of 88.2% and specificity of 87.5%, respectively. Likelihood ratios （LR） indicate that absorbances lower than 0.209 were at least 11.3 times as likely to be found in good semen samples than those in poor according to the SI, whereas in the case of motile sperm concentration, the LR was calculated to be 7.06. Conclusion： These results show that the resazurin reduction assay combined with spectrophotometry is an accurate method of assessing the quality of boar semen.

Study on divertor heat flux under n=3 and n=4 resonant magnetic perturbations using infrared thermography diagnostic in EAST

Resonant magnetic perturbations(RMPs)with high toroidal mode number n are considered for controlling edge-localized modes(ELMs)and divertor heat flux in future ITER H-mode operations.In this paper,characteristics of divertor heat flux under high-nRMPs(n=3 and 4)in H-mode plasma are investigated using newly upgraded infrared thermography diagnostic in EAST.Additional splitting strike point(SSP)accompanying with ELM suppression is observed under both RMPs with n=3 and n=4,the SSP in heat flux profile agrees qualitatively with the modeled magnetic footprint.Although RMPs suppress ELMs,they increase the stationary heat flux during ELM suppression.The dependence of heat flux on q_(95)during ELM suppression is preliminarily investigated,and further splitting in the original strike point is observed at q 495=during ELM suppression.In terms of ELM pulses,the presence of RMPs shows little influence on transient heat flux distribution.

Determination of a Cut-Off Point of a Scale for Achievement Motive in Geriatrics That Predicts the Frequency of Undertaking Instrumental Activities of Daily Living in Community-Dwelling Elderly People

Background: Among elderly people, rehabilitation is important for reducing the risk of falls and hospitalization and to maintain an independent life for longer. Motivation is a factor for elderly people to lead an active daily life and leave home more frequently. Purpose: The purposes of this study were to determine the optimal cut-off point in the Scale for Achievement Motive in Geriatrics (SAMG) that could identify individuals as inactive or active, based on the Frenchay Activities Index (FAI), and to compare characteristics between active and inactive groups classified by the cut-off point. Methods: A cross-sectional study of 285 community-dwelling elderly people measured SAMG and FAI and physical function. Receiver operating characteristic (ROC) analysis was used to calculate the area under the curve (AUC) that was the optimal cut-off point for the SAMG total score, with the associated sensitivity and 1-specificity when compared with the FAI results. Demographic parameters and physical function were compared between two groups defined by cut-off point. Results: The AUC was 0.78, the optimal cut-off for SAMG total score for indicating inactivity was ≤48, the sensitivity was 77.98% and the 1-specificity was 75.00%. The group with SAMG score >48 was characterized by a significantly higher proportion of women, fewer people sharing a house, and participation in more hobbies. Discussion: A cut-off point of 48 in the SAMG could be a predictive index of motivation toward goals for individuals with inactive daily activities. The group with score higher than the cut-off was characterized by more women, fewer people living together, and more hobbies than the group with lower scores.

危害分析和关键控制点法在产前诊断技术服务医疗风险管理中的研究与应用

本文运用危害分析和关键控制点(HACCP)法对产前诊断技术服务医疗风险进行管控,以提高医疗机构风险防控效能,保障母婴安全。通过对产前诊断技术服务流程进行危害分析,建立4个维度(资质管理和组织建设、临床技术、实验室检测技术、医学影像诊断技术)18个关键控制点(CCP),针对CCP制订计划、实施管控措施、评价管控效果。HACCP实施后,产前诊断技术服务的风险行为减少,不良医疗结局(漏诊、误诊、投诉举报、医疗纠纷、行政处罚)发生率降低,同时,构建科学有效的风险管控体系,提高了机构及工作人员的风险预警意识和诊断技术水平。

Interpretation of data and treatment of Jing-well point temperatures test

The Jing-well point temperatures test method is a method to diagnose and guide the treatment of diseases by measuring the subjects' symmetrical well point temperature. it is improved from the method of knowing heat sensitivity. The application of Jing-well point temperatures test method is wide, and it can be used in internal and external gynecology and pediatrics and facial features department. at the same time, it has the advantage of objective and accurate diagnosis. The old law has some shortcomings, such as poor intuition, unavoidable omission of information, incomplete interpretation of information and so on. In this paper, Excel software is used to transform the data into line chart form, which improves the intuition and comprehensiveness of this method, so that the data can be better interpreted and used. It is newly proposed in this article that in addition to observing the longitudinal di fference of well point temperature, more attention should be paid to the horizontal contrast difference of well point temperature in different meridians. The article also summarizes a number of treatment methods, including acupuncture, moxa moxibustion, cupping and scraping, and the selection of acupoints, including mother acupoints, tenderness points and heat-sensitive moxibustion, so that doctors can combine traditional Chinese medicine professional knowledge in clinic.

模型参数点估计的可靠性:以CDM为例

心理学研究中,不恰当的模型参数估计框架或收敛准则严重影响模型参数点估计的可靠性,进而影响到研究结论的可靠性。本研究提出了基于MLE-EM的CDM模型参数估计新框架,以及新收敛判断方法。通过模拟研究与实证数据分析的方式,探索了新参数估计框架和新收敛判断方法的表现,并与已有模型参数估计框架及收敛判断方法进行了比较。结果显示,新的模型参数估计框架及收敛准则的表现优于已有的模型参数估计框架及收敛准则,能有效提高模型参数点估计的可靠性。

C肽及胰岛自身抗体在糖尿病分型诊断中的价值研究

目的探讨空腹C肽(FC-P)、餐后2小时C肽(P2hC-P)及胰岛自身抗体在糖尿病分型诊断中的价值。方法分析148例1型糖尿病(T1DM)患者与353例2型糖尿病(T2DM)患者的基本特征、实验室检查结果(包括C肽水平、胰岛自身抗体)存在的差异。根据病程将各型患者又分别分为3个亚组(0~年组、2~年组、5~年组),比较各亚组患者入院时及胰岛素强化治疗后的FC-P、P2hC-P水平差异。绘制ROC曲线分析FC-P、P2hC-P对糖尿病分型的诊断价值。结果T2DM患者年龄、病程、BMI、FC-P、P2hC-P均高于T1DM患者(均P<0.01),两组空腹血糖(FBG)、糖化血红蛋白(HbA1c)水平的差异无统计学意义(均P>0.05)。T2DM组患者谷氨酸脱羧酶抗体(GADA)、胰岛细胞抗体(ICA)、蛋白酪氨酸磷酸酶抗体(IA-2A)、锌转运蛋白8抗体(ZnT8A)均为阴性,T1DM患者GADA、ICA、胰岛素自身抗体(IAA)、IA-2A、ZnT8A的水平均显著高于T2DM患者(均P<0.01)。T2DM不同病程亚组患者的FC-P、P2hC-P水平均高于T1DM组(均P<0.05)。ROC曲线分析显示病程<2年的患者入院时检测FC-P、P2hC-P明确糖尿病分型的最佳临界值分别为0.165nmol/L、0.323nmol/L;胰岛素强化治疗后检测FC-P、P2hC-P的最佳临界值分别为0.318nmol/L、1.268nmol/L。胰岛素强化治疗后P2hC-P的AUC最大,为0.938,灵敏度为92.91%,特异度为88%,诊断准确度较高。结论C肽可作为鉴别T1DM、T2DM的指标,且餐后C肽的诊断价值高于FC-P,同时联合GADA、ZnT8A、IA-2A及年龄、BMI等临床特征可降低T1DM的临床漏诊率及误诊率。

分子诊断试剂设计开发过程的关键控制点和常见问题分析

分子诊断试剂的设计开发过程是体外诊断试剂质量管理体系的关键环节。该研究结合分子诊断体外诊断试剂的技术设计特点,分析设计开发过程中应关注的关键控制点。同时从注册质量管理体系角度出发,分析设计开发过程的常见问题,旨在为企业开展该类试剂的设计开发及注册质量管理体系建立提供技术参考,提高企业的产品研制效率,优化企业的质量管理体系,提升注册申报效率及质量。

Integrated microfluidic devices for in vitro diagnostics at point of care

Given the continuous and growing demand for point of care(POC)diagnostic tests,attention has been shifted toward integration and miniaturization of laboratory protocols into“sample-in-answer-out”devices.Microfluidic technologies have been considered an ideal solution to address the requirements of POC diagnostics since many laboratory functions can be miniaturized and incorporated onto a single integrated chip.In this review,we summarize the advances of integrated microfluidic devices for POC diagnostics in the last 3 years.Particularly,we summarize current materials used for microfluidic chip fabrication,discuss the innovation of versatile integrated microfluidic devices,especially the strategies for simplifying sample preparation in manual or self-driven systems,and new detection methods of microfluidic chips.In addition,we describe new integrated microfluidic devices for POC diagnostics of protein-targeted immunodiagnostics,nucleic acid molecular tests,and small molecule metabolites analysis.We also provide future perspectives and current challenges for clinical translation and commercialization of these microfluidic technologies.

Real-time electrical detection of epidermal skin MoS2 biosensor for point-of-care diagnostics

Various approaches have been proposed for point-of-care diagnostics, and in particular, optical detection is preferred because it is relatively simple and fast. At the same time, field-effect transistor （FET）-based biosensors have attracted great attention because they can provide highly sensitive and label-free detection. In this work we present highly sensitive, epidermal skin-type point-of-care devices with system-level integration of flexible MOS2 FET biosensors, read-out circuits, and light-emitting diode （LEDs） that enable real-time detection of prostate cancer antigens （PSA）. Regardless of the physical forms or mechanical stress conditions, our proposed high-performance MoS2 biosensors can detect a PSA concentration of 1 pg.mL-1 without specific surface treatment for anti-PSA immobilization on the MoS2 surface on which we characterize and confirm physisorption of anti-PSA using Kelvin probe force microscopy （KPFM） and tapping-mode atomic force microscopy （tm-AFM）. Furthermore, current modulation induced by the binding process was stably maintained for longer than 2-3 min. The results indicate that flexible MoS2-based FET biosensors have great potential for point-of-care diagnostics for prostate cancer as well as other biomarkers.

评价卡托普利试验诊断原发性醛固酮增多症的价值

目的:评价卡托普利试验对于原发性醛固酮增多症的诊断意义,并计算最佳诊断切点。方法:1994-06至2012-05期间解放军总医院内分泌科收治的96例综合临床表现、实验室检查及辅助检查明确诊断为原发性醛固酮增多症患者为原发性醛固酮增多症组,同时收集45例高度怀疑原发性醛固酮增多症,并经生化检查、辅助检查及功能试验检查结果排除原发性醛固酮增多症,被诊断为原发性高血压的患者为原发性高血压组。住院期间患者均行卡托普利试验,并应用受试者工作特征(ROC)曲线对卡托普利试验的醛固酮水平及试验后醛固酮与肾素水平进行评价,分析其诊断效能,并得出最佳诊断切点及对应的敏感性和特异性。结果 :卡托普利试验后1 h、2 h的醛固酮水平的ROC曲线下面积(AUC)为0.831和0.818,试验后1 h、2 h的醛固酮与肾素比值的AUC分别是0.909和0.922;试验后1 h醛固酮水平的切点为544.95 pmol/L,敏感性为70%,特异性为90.7%,试验后2 h醛固酮水平的切点为466.8 pmol/L,敏感性为69.8%;特异性为70.5%;试验后1 h醛固酮与肾素比值的切点为34.6[ng/dl:μg/(ml·h)],敏感性78.3%;特异性88.4%。试验后2 h醛固酮与肾素比值的AUC最大,该指标有较高的诊断价值,诊断切点为42.2[ng/dl:μg/(ml·h)],敏感性和特异性分别为76.7%和95.3%。结论:卡托普利试验后1 h、2 h后醛固酮水平及醛固酮与肾素的比值均对原发性醛固酮增多症有诊断价值,以卡托普利试验后2 h醛固酮与肾素比值的诊断价值最大。

耳穴诊断技术研究进展

目的:探讨目前耳穴诊断技术的研究进展。方法:通过检索近20年国内外耳穴诊断技术的相关文献,并从传统耳穴诊断技术、近年新技术和国外的耳穴诊断技术这3方面分析总结目前耳穴诊断方式和技术的应用状况及利弊。结果:目前国内耳穴诊断技术方法众多,每项技术具有其优缺点,综合运用这些技术能大大提高诊断疾病的准确性,但耗时、耗力、费用相对高。同时,与中国不同原理的欧洲耳穴诊断技术则具有快捷、高效、相对廉价等优点,但缺点是该诊断技术找到的是治疗点,与疾病的诊断、疾病的性质不存在确定的相关性。结论:我国亟需挖掘简便、客观、全面检测病变部位的耳穴诊疗技术,因此把我国与欧洲诊断技术相结合进行研究,有可能是耳穴诊断技术发展的一个新方向。

神光Ⅲ主机通用诊断搭载平台的研制

神光Ⅲ主机通用诊断搭载平台提供各种诊断系统送进和收回的搭载功能,便于诊断系统的拆装和维护保养,同时提供精确的径向、指向瞄准能力,能将诊断系统送至靶室内指定位置,并且能在不破坏靶室真空的状态下安装、调试和维护诊断系统。将通用诊断搭载平台安装在神光Ⅲ原型装置上进行精度检测,得到其真空状态下的径向、X和Y方向指向定位精度分别为36,13,8μm,全行程的径向复位精度、X和Y方向指向复位精度分别达到20,30,12μm。搭载分幅相机诊断包进行激光打靶考核,实验结果表明:其指向瞄准精度、真空性能、接口等均满足使用要求,并具备了对抗强电磁干扰与辐射的能力。

短时强降水诊断物理量敏感性的点对面检验

对诊断物理量的准确认识可以帮助提高短时强降水的预报准确率,并帮助理解产生短时强降水的可能机制。考虑我国降水观测网的布设特点,结合NCEP最终分析资料的物理量场,以大气水汽总量和最优抬升指数为例,通过点对面检验分析了多个用于表征短时强降水环境特征的诊断物理量的敏感性。结果表明:常规的点对点检验是点对面检验的特殊情况。大气水汽总量和最优抬升指数对短时强降水的指示均存在最佳阈值,且140 km范围内的大气状况才对某点3 h内能否出现短时强降水有直接影响。对于水平分辨率为1°×1°的NCEP资料,建议点对面检验的搜索半径和记录数阈值分别为140 km和2个记录。对多个诊断物理量对比分析显示,短时强降水对水汽相关量最为敏感,其次是表征热力条件的物理量,而表征动力条件和垂直风切变的量的指示意义不够显著。

不同年龄层次糖尿病患者糖化血红蛋白诊断标准研究

目的探讨不同年龄层次的糖尿病患者糖化血红蛋白(Hb A1c)诊断标准。方法选取210例患者,以60岁为分界点,分别计算<60岁的患者和≥60岁患者的Hb A1c诊断切点。结果 1210例患者尤登指数最大点所对应的Hb A1c切点为6.2%,其诊断敏感性为71.5%,特异性为35.1%;2Hb A1c≥6.2%患糖尿病率为75.4%;Hb A1c<6.2%患糖尿病率为31.0%,差异有统计学意义(P<0.01);3年龄≥60岁的患者尤登指数最大点所对应的Hb A1c切点为6.3%,年龄<60岁的患者尤登指数最大点所对应的Hb A1c切点为6.0%;4在≥60岁的患者中,以切点6.3%作为诊断切点对糖尿病诊断率明显高于以6.2%为诊断切点的诊断率(P<0.05);在<60岁的患者中,以切点为6.0%作为诊断切点对糖尿病诊断率明显高于其他两个诊断切点(P<0.05)。结论不同年龄层次Hb A1c诊断切入点不同,≥60岁的患者诊断切入点为6.3%,<60岁的患者诊断切入点为6.0%。

X射线点投影技术在高能量密度物理相关实验中的应用

利用激光驱动4.8 keV左右的Ti等离子体X射线源作为背光,通过静态成像实验研究了针孔辅助点投影诊断方法及其特点。进行了点投影技术动态诊断应用探索,建立了光子能量约4.8 keV、时间分辨力约100 ps、空间分辨约10μm的动态诊断实验平台。并简要介绍了此诊断平台上开展的流体力学不稳定性研究、激光加速射流、材料预压缩特性研究等一系列实验结果。

湿地边界确定研究进展

本文分析了目前湿地边界确定存在的困难及各种湿地边界指标及其标准在湿地边界确定过程中存在的问题,将系统论的基本原理与自然地理学相结合,分析了湿地系统与陆地系统和水体系统之间本质特征的区别,认为:由于湿地边界存在的客观性,湿地边界确定的困难并不能说明其边界就不能确定;用人为“规定”的标准来确定湿地的边界是不科学的,任何自然综合体的边界只能认识而不是人为规定的;由于湿地多样性,从湿地本身特征无法确定湿地边界的情况下,由于湿地是位于水陆交错带的一个自然综合体,只要抓住了湿地隐域性的本质,确定了水体系统与陆地系统的边界也就确定湿地系统的边界。通过对湿地边界各种指标的合理性和可重复性分析,提出地带性土壤诊断层尖灭点作为湿地边界指标,分析了其科学性和可行性,并提出了湿地边界确定的方法。