Dried blood spots,valid screening for viral hepatitis and human immunodeficiency virus in real-life

AIM To detect chronic hepatitis B(CHB),chronic hepatitis C(CHC) and human immunodeficiency virus(HIV) infections in dried blood spot(DBS) and compare these samples to venous blood sampling in real-life.METHODS We included prospective patients with known viral infections from drug treatment centers,a prison and outpatient clinics and included blood donors as negative controls. Five drops of finger capillary blood were spotted on filter paper,and a venous blood sample was obtained. The samples were analyzed for HBs Ag,antiHBc,anti-HBs,anti-HCV,and anti-HIV levels as well as subjected to a combined nucleic acid test(NAT) for HBV DNA,HCV RNA and HIV RNA.RESULTS Samples from 404 subjects were screened(85 CHB,116 CHC,114 HIV and 99 blood donors). DBS had a sensitivity of > 96% and a specificity of > 98% for the detection of all three infections. NAT testing did not improve sensitivity,but correctly classified 95% of the anti-HCV-positive patients with chronic and past infections. Anti-HBc and anti-HBS showed low sensitivity in DBS(68% and 42%).CONCLUSION DBS sampling,combined with an automated analysis system,is a feasible screening method to diagnose chronic viral hepatitis and HIV infections outside of the health care system.

The Use of Dried Blood Spot Samples in Screening Drugs of Abuse

The present article will provide an overview of use of dried blood sampling method for analysis of drug of abuse. Relatively short half life and instability in blood, calls for alternative sampling method for determination of drugs of abuse. Dried blood spot (DBS) method has many advantages over the conventional sampling methods. The available method for DBS sample collection, storage and transport are described here. The techniques involved in and the factors that may influence the accuracy and reproducibility of the DBS methods for determination of drugs of abuse are presented. The DBS sampling has the potential to be a useful technique to detect drugs of abuse. The use of DBS for any drug should be judged against the potential error involved with the method.

Ethical and Regulatory Issues with Residual Newborn Screening Dried Bloodspots

After newborn screening is completed, most states retain leftover dried bloodspots. These dried bloodspots are stored for varying lengths of time among different state newborn screening programs. Dried bloodspots are a unique and valuable resource for the development of new newborn screening tests, quality assurance and biomedical research. Recent changes to the 2014 Newborn Screening Reauthorization Saves Lives Act require explicit parental consent for the retention and use of dried bloodspots in federally funded research. This has raised several ethical and regulatory issues and highlighted the challenges of respecting individual autonomy and public health goals. This article provides an overview of these issues and discusses methods for obtaining parental consent. These issues may be applicable to consent for the storage and use of biospecimens among other settings according to proposed changes to the Common Rule.

Productive test of a newly drying technology of veneer： intermittent-contact drying of veneer with flexible screen belt

A newly drying technology, intermittent-contact drying of veneer with flexible screen belt (ICD-fbs), was invented and used in poplar veneer drying. Productive test was carried out for validating the practical use of this drying method. The test result shows that to dispose flexible screen belts on the two sides of hot board could help steam discharge remarkably. The veneer dried using ICD-fsb method had smooth and level surface, less deformation and warping, even moisture content, and high utilization rate. The time for opening hot board to discharge steam,which, early or late, is a key to obtain good drying result, was determined at the time when the core's temperature of veneer reaches 100℃ (vaporization). Using ICD-fsb method, the shrinking rates in tangent of veneer were from 1.90% to 2.26% for veneer of 0.4 mm in thickness,2.49% to 4.50% for veneer of 1 mm in thickness and 1.34% to 3.30% for veneer of 1.7 mm in thickness, which are much lower than the results obtained by other drying methods. The method of ICD-fsb offers a reliable technological guarantee for solving the deformation problem of veneer drying, especially the deformation of wood from quick-growing plantation.

A Study on contact drying with flexible screen

Three types of material as platen in contact drying process were tested in Composition Board Laboratory of Northeast Forestry University in 1998. Poplar veneers were dried under’0.3 MPa at 160℃ or 180℃. Through comparison a non-metal flexible material was chosen as screen for designing contact dryer and replacing curved metal plate. The new type contact dryer solved the problem of long auxiliary time by loading wet veneers into press and unloading dried veneers out of press at the same time. This increased productivity. Veneer’s moisture content(MC) varied with drying time in index law. The process of contact drying with non-metal flexible screen was analyzed by stages of preheating, high-speed drying, retarded drying and extremely slow drying.

Study on drying rate in contact drying with flexible screen

The moisture contents (MC) of popular veneers were tested in Composition Board Laboratory of Northeast Forestry University by contact drying with flexible screen. The influence factors considered included temperature, initial moisture contents (IMC), and veneer thickness. Veneer-drying laws under different hot press conditions were analyzed. The results showed that the drying rate increased with temperature rising. 160°C was considered to be more efficient than 140°C and 180°C because excessive high temperature has no significant contribution to drying rate. IMC had significant effect on drying rate. The veneer with high IMC had a higher drying rate at above fiber saturation point (FSP) and a lower drying rate at below FSP, compared to the veneer with low IMC. Average drying rate also varied with thickness in power law.

Screening of New High Quality and High Yield Sweet Potato Varieties in Zaozhuang of Shandong Province

[Objectives]To compare the growth period,dry matter content and yield of 12 different sweet potato varieties,so as to screen out new sweet potato varieties with high yield,high quality and high dry matter content suitable for cultivation in Zaozhuang of Shandong Province.[Methods]Field random arrangement,three replicates,and field observation were adopted,and data were surveyed and summarized.[Results]There were significant differences in the maturity period between varieties.Longshu 9,Hongxiangjiao,Sushu 8,Yanshu 25,and Yanshu 0747 in the fresh eating group were mature earlier,and Yuzi 7 was mature later;Xushu 32 in the starch group was mature earlier,while Xushu 22(ck),Shangshu 19,Jishu 25,and Jishu 98 had moderate maturity period,and Jixu 23 was mature later.The difference in the yield between the fresh eating group and the starch group reached a very significant level.In the fresh eating group,Yanshu 25 had the highest yield,followed by Longshu 9,and then Yanshu 0747;in the starch group,Jishu 98 had the highest yield,followed by Shangshu 19,and then Jixu 23.Besides,there were significant differences in the dry matter content between varieties.In the fresh eating group,Yuzi 7 had the highest dry matter content(30.4%),followed by Yanshu 25(28.1%),and then Yanshu 0747(28.1%);in the starch group,Xushu 32 had the highest dry matter content(33.6%),followed by Jishu 25(32%),and then Jishu 98(31.5%).[Conclusions]Combining the maturity period,yield,dry matter content,appearance,taste and unique ecological conditions in Zaozhuang area,the varieties suitable for cultivation in Zaozhuang area were screened:in the fresh eating group,it was Yanshu 25 and Longshu 9;in the starch group,it was Jishu 98,Shangshu 19,and Jixu 23.

THE PARAMETER DESIGN AND THE MECHANICAL MODEL OF PIANOWIRE PROBABILITY SCREEN

Based on the analysis of the piano wire’s vibration characteristics, the authors estab lished the mechanical model of piano wire proba bility screen , obtained the analytic so lution of thestable forced vibration of screen wires , and developed the para meter designfor m ula of the piano wire screen . The para meter design form ula has been used in coalpreparation industry .

RESEARCH ON THE QGS2020 TYPE PIANO-WIRE PROBABILITY SCREEN

Integrating the probability screen with the piano-wire screen, the authors developed the QGS2020 type piano-wire probability screen (PWPS), a new screen which has a large capacity, high efficiency, and no blinding. The results of the indus trial tests show that this screen is suitable for dry sCreening the fine particles from high-moisture raw coal. This paper describes the operation principles, the structure features and the mechanical model of the QGS2020 type PWPS, and also includes data from industrial tests.

THE DEVELOPMENT OF PIANO——WIRE PROBABILITY SCREEN

The Probability Sizing Screen (PSS) developed by China University of Mining and Technology has been used since 1980 for the screening of moist fine raw coal. More than 600PSS's have been installed in Chinese coal mines, bringing about economic benefits to both coal producers and consumers in terms of reduced energy saving, transpertation cost reduction,and environmental protection. While the PSS treats some high-moisture fine raw coal, the mesh apertures may be blinded by the fine particles stuck on the mesh wire of the screen. Recently, the authors have developed the Piano-wire Probability Screen, a new screen which screens moist fine raw coal. This screen assimilates advantages of PSS, having large deck inclination, large aperture and multideck. In addition the new screen uses piano-wire decks which have a new structure, great open area, and no blinding. The results of sizing fine moist raw coal in Lugou Coal Mine, Henan Province,show that the Piano-wire Probability Screen has a large capacity and high efficiency and is an efficient screen for separating moist raw coal with diameter of 6mm. This paper describes the results of fundamental studies on the Piano-wire Probability Screen. and also includes data from pilot-plant studies.

Evaluating Low Cost and Sustainable High Quality Cassava Drying Technologies among Small and Medium Processors in Uganda

Cassava regarded as a white gold of Africa is driving the agricultural commercialization and industrialization with small to medium technologies in Uganda. There is an over-whelming demand for high quality cassava flour （HQCF） by Bakeries, beverage industry, paper board and composite end markets. The end market for HQCF dictates on its quality attributes and rewards for its quality in terms of price offered within their minimum standards. However, obtaining sustainable amounts of HQCF for these markets calls for devoted efforts. Limited types of HQCF processing technologies exist and if they exist, their efficiency, costs and sustainability are not well understood. We evaluated high quality cassava drying technologies in Northern and Eastern Uganda in two years using naturally ventilated wooden screen solar drying structures and open air sun drying structures. Naturally ventilated wooden screen solar dryers produced clean dry high quality cassava chips free off insect and bird contamination and caused faster drying to less than 14.3% MC in 1.5 hours than open outside drying conditions. We recommend naturally ventilated wooden screen solar dryers for small and medium cassava processors during dry and rainy season. Halftone to one tone cassava chips dryers per day drying unit can cost one 2,258-4,338 USD to make it functional. Also open outside raised metallic racks with black surface can give good results on a good sunny day especially for starters on small scale basis. A small durable unit of 150 kilograms per day can be made with 500 USD.

对辊式干辣椒脱帽装置设计与试验

针对辣椒机械化脱帽存在的辣椒损伤大、辣椒蒂去除不净等问题,结合辣椒物理力学特性及机械化加工要求,设计了一种对辊式干辣椒脱帽装置。该装置关键部件包括滚筒、脱帽辊和筛网3部分,采用旋转滚筒和回转辊轴的方式实现辣椒脱帽。通过对脱帽装置工作过程分析,确定了去除辣椒蒂的临界条件。借助辣椒受力及运动特征研究,确定了滚筒及脱帽辊的关键参数。滚筒直径为1.8 m、长度为6.0 m、转速为28.83 r/min,脱帽辊的直径为36.0 mm、间隙为0.5 mm、转速为134.21 r/min。通过对筛面利用系数分析,确定了筛分效率较高的方形筛网,且筛面利用系数为60.5%。通过Design-Expert 12软件进行试验设计及数据处理,明确了滚筒转速、脱帽辊转速对损伤率、脱净率的影响规律,并确定了较优参数组合,为辣椒机械化加工技术及装备研发提供理论依据。试验结果表明,该装置损伤率为0.6%,脱净率为98.8%,符合行业标准且满足辣椒机械加工要求。

干血斑中34种苯二氮卓类物质的实时直接分析-串联质谱快速筛查研究

该文通过优化仪器条件和前处理方法建立了实时直接分析-串联质谱快速筛查干血斑(DBS)中34种苯二氮卓类物质(BZDs)的方法。首先将50μL血液沉积在采血卡上形成DBS,DBS经溶剂充分提取后取上层溶液,使用DART 12Dip-It^(TM)模块进样5μL,在多反应监测模式下检测。结果表明:选用400℃作为载气加热器温度,以乙酸乙酯-水(体积比3∶1)混合溶剂提取DBS样品,所得响应强度较高且建立的筛查方法选择性良好,无延迟效应影响,除阿地唑仑、奥沙西泮和α-羟基三唑仑外,其他物质的检出限均在5~50 ng/mL。所建方法可在90.3%的阳性检材中成功筛选出BZDs物质,方法快速、简便、有效,适用于服药自杀等类案件中DBS检材的快速筛查检验。

Optimization and application of a dried blood spot-based genetic screening method for thalassemia in Shenzhen newborns

Background To optimize and apply an approach suitable for large-scale neonatal thalassemia genetic screening in China,thalassemia genotypes were determined by polymerase chain reaction-reverse dot blot using DNA extracted from dried blood spots(DBS)obtained from newborn screening programs.Methods Firstly,the most suitable commercial DNA extraction kit for DBS was screened.Then,the appropriate amount of DBS required for the automated high-throughput DNA extraction system was evaluated.Finally,the thalassemia prevalence and genotype spectrum in Shenzhen were investigated in 2028 newborns using the optimized screening procedure.Results The Magentec extraction kit was best suited for the automated DBS DNA extraction system using eight 3-mm DBS discs.The neonatal thalassemia prevalence in Shenzhen was 9.12%;6.31%α-thalassemia,2.37%β-thalassemia,and 0.44%α-/β-thalassemia.Conclusions Genetic screening based on DBS can precisely identify the thalassemia genotypes.Bothα-andβ-thalassemia are widely distributed in Shenzhen newborns.Newborn genetic screening is important for establishing a comprehensive thalassemia prevention program and for public education.

干血斑保存温度对新生儿遗传代谢病筛查结果的影响

目的探讨血斑卡在不同储存温度条件下对筛查标志物检测结果的影响,为提高新生儿遗传代谢病筛查前样本质量提供参考依据。方法纳入宜宾市妇幼保健院新生儿100例,每例采集干血斑3份,分别放置于2~8℃冷藏、20~24℃常温及37℃孵箱三种不同温度,储存48小时后进行新生儿遗传代谢病筛查,对不同储存条件下的结果进行分析。结果TSH、Phe、17α-OHP及G-6-PD四项指标的在不同保存条件下的检测结果均存在差异(P<0.05)。以低温存储的样本作为参考,发现37℃储存样本检测结果的精密度、及与参考值的相关性相对于常温存储均有所下降。从筛查结果的角度,37℃样本检测中产生了大量的假阳性结果,尤其是在G-6-PD缺乏症的检测中,假阳性率达到了90%。结论样本保存不当可能影响检测精密度、增加检测假阳性率。干血斑样本应尽量在低温运输及存储,尤其应当避免暴露于37℃及以上的环境,避免因保存不当产生假阳性结果。

Screening of amino acids in dried blood spots by stable isotope derivatization-liquid chromatography-electrospray ionization mass spectrometry

Direct infusion mass spectrometry(DIMS) is a powerful technique in clinical diagnosis for screening neonatal amino acid metabolic disorders from dried blood spots(DBS).However,DIMS sometimes generated false-positive results for analysis of amino acids.In this work,we utilized a stable isotope derivatization method,combining with liquid chromatography tandem mass spectrometry(SID-LC-MS),to improve the specificity for screening amino acids in DBS specimens.A pair of isotope reagents,p-(dimethylamino)phenyl isothiocyanate(DMAP-NCS) and 4-isothiocyanato-N,N-bis(methyl-[2H2])aniline([2H4]DMAP-NCS),was synthesized and used to label amino acids in DBS specimens.The [2H4]DMAP-NCS labelled amino acid standards were used as internal standards to compensate the matrix effect.This method was validated by measuring linearity,recovery and accuracy.The results showed that the developed SID-LC-MS method can be used for sensitive and selective determination of 12 diagnostically important amino acids in DBS specimens.

HIV screening and retention in care in people who use drugs in Madrid, Spain: a prospective study

Background::The burden of human immunodeficiency virus(HIV)infection in people who use drugs(PWUD)is significant.We aimed to screen HIV infection among PWUD and describe their retention in HIV care.Besides,we also screen for hepatitis C virus(HCV)infection among HIV-seropositive PWUD and describe their linkage to care.Methods::We conducted a prospective study in 529 PWUD who visited the"Ca?ada Real Galiana"(Madrid,Spain).The study period was from June 1,2017,to May 31,2018.HIV diagnosis was performed with a rapid antibody screening test at the point-of-care(POC)and HCV diagnosis with immunoassay and PCR tests on dried blood spot(DBS)in a central laboratory.Positive PWUD were referred to the hospital.We used the Chi-square or Fisher’s exact tests,as appropriate,to compare rates between groups.Results::Thirty-five(6.6%)participants were positive HIV antibodies,but 34 reported previous HIV diagnoses,and 27(76%)had prior antiretroviral therapy.Among patients with a positive HIV antibody test,we also found a higher prevalence of homeless(P<0.001)and injection drug use(PWID)(P<0.001),and more decades of drug use(P=0.002).All participants received HIV test results at the POC.Of the 35 HIV positives,28(80%)were retained in HIV medical care at the end of the HIV screening study(2018),and only 22(62.9%)at the end of 2020.Moreover,12/35(34.3%)were positive for the HCV RNA test.Of the latter,10/12(83.3%)were contacted to deliver the HCV results test(delivery time of 19 days),5/12(41.7%)had an appointment and were attended at the hospital and started HCV therapy,and only 4/12(33.3%)cleared HCV.Conclusions::We found almost no new HIV-infected PWUD,but their cascade of HIV care was low and remains a challenge in this population at risk.The high frequency of active hepatitis C in HIV-infected PWUD reflects the need for HCV screening and reinforcing the link to care.

新疆杏制干品种的筛选及制干工艺的初步研究

【目的】筛选适宜的杏制干品种并对其制干工艺进行研究。【方法】对大胡安娜、佳娜丽、库买提、赛买提等46个杏品种的鲜杏自然晾晒制干,通过对46个品种的杏干果肉的总糖、总酸、制干比等指标测定及感官评价,筛选出适宜的杏制干品种。以库买提为原料,通过采用促干剂、蒸汽漂烫、NaHSO3溶液浸泡、漂烫结合NaHSO3溶液浸泡等处理方法,经过自然晾晒得到杏干,并对杏干的总糖、总酸、制干比、水分、残留SO2量进行测定以确定最佳制干工艺。【结果】适宜的制干品种为大胡安娜、黑叶杏、库买提、佳娜丽等。最佳制干工艺条件为整果经90℃热水漂烫3 min,再浸泡于浓度为3.75 g/L的NaHSO3溶液中1 h后晾晒。【结论】采用该工艺提高了制干速率,制干时间缩短2 d,且杏干感官品质好。

GSP分析仪筛查新生儿疾病的性能验证和应用

目的用全自动荧光免疫分析仪(Genetic Screening Processor,GSP)检测新生儿先天性甲状腺功能减低症(congenital hypothyroidism,CH)和先天性肾上腺皮质增生症(congenital adrenal hyperplasia,CAH)筛查的指标——促甲状腺激素(thyroidstimulating hormone,TSH)和17羟基孕酮(17-OH-progesterone,17-OHP),评估GSP应用于临床的可行性。方法检测美国疾病预防与控制中心(Centers for Disease Control and Prevention,CDC)的滤纸干血片标本和GSP配套试剂盒内质控品,计算GSP的正确度、精密度和线性;检测临床明确诊断的标本,TSH 1 012例(阳性60例,阴性952例)和17-OHP 991例(阳性34例,阴性957例),ROC曲线统计确定初始cut-off值,比对与临床诊断的一致性。结果 TSH和17OHP的批内不精密度分别为6.69%~12.6%和7.52%~9.29%,批间不精密度分别为6.91%~10.96%和6.86%~12.36%;偏移分别为-14.28%^-0.74%和-0.45%~12.54%;检测结果线性良好;初始cut-off值为23.43 U/m L(TSH)和21.42 ng/m L(17-OHP),敏感性为100%,特异性依次为98.11%和99.58%,与临床诊断结果一致性好。结论 GSP作为新生儿疾病筛查领域的首台全自动荧光免疫分析仪,满足实验室要求,可作为常规技术应用于CH和CAH的筛查。

分离自腌干鱼的抗氧化发酵菌株的筛选及鉴定

以符合耐盐、耐高低温、产酸等要求和过氧化氢耐受能力为指标,对分离自传统腌干鱼制品的29株乳酸菌进行初筛,再以抗脂质过氧化率、羟自由基清除率和还原力为复筛指标评价了菌株不同组分的体外抗氧化能力,以期获得具有优良抗氧化活性的发酵菌株。结果表明,15株乳酸菌符合腌干鱼发酵要求,菌株间的抗氧化活性差异明显,其中以L4、L11和L21综合抗氧化活性最好。经VITEK-2微生物鉴定系统和16S r DNA分子鉴定,确定L4、L11和L21分别为戊糖片球菌(Pediococcus pentosaceus)、植物乳杆菌(Lactobacillus plantarum)和干酪乳杆菌(L.casei)。