bluuebunny/crossref_metadata_2025_split huggingface dataset:
Properties and clinical significance of an alkaline phosphatase-lipoprotein-X complex.
Authors: Weijers R N 
Published: February 2020

Abstract
The existence of an alkaline phosphatase-lipoprotein-X complex was demonstrated as an abnormally moving band in the agar-agarose gel alkaline phosphatase pattern of sera from 58 patients in a group of 72 patients whose sera contained lipoprotein-X. The position of the abnormally moving band in the agar-agarose gel alkaline phosphatase pattern and the percentage of alkaline phosphatase activity in the complex in relation to the total serum alkaline phosphatase activity depend on the serum lipoprotein-X concentration. The presence of the complex is a reliable indicator for cholestasis and of limited value in the differentiation between intrahepatic and extrahepatic cholestasis.
Improved separation of creatine kinase isoenzymes by use of DEAE-Sepharose Cl-6B.
Authors: Bondar R J , Shevchik D G , Hsu M Y , Kohler M M 
Published: February 2020

Abstract
We describe here a simple, rapid chromatographic procedure for quantitatively separating serum creatine kinase isoenzymes (EC 2.7.3.2), with diethylaminoethyl (DEAE)-Sepharose CL-6B as the anion-exchanger. We established the column bed height and the elution parameters by use of a simplex procedure. DEAE-Sepharose CL-6B equilibrated in tris(hydroxymethyl)aminomethane (50 mmol/L, pH 7.5, and containing 30 mmol of NaCl per liter) is packed into a miniature polystyrene column with bed dimensions of 0.7 x 1.5 cm. The DEAE-Sepharose column system was evaluated and compared with a DEAE-Sephadex A-50 column system. The results indicate that the Sepharose column yields MM, MB, and BB isoenzymes uniquely, without cross contamination. Coefficients of variation (CV’s) for 10 replicate column assays were 2.8, 5.9, and 15.2% for 569 U of MM per liter, 82.3 U of MB per liter, and 9.0 U of BB per liter, respectively. The serum sample was enriched with baboon heart extract. Day-to-day reproducibility for a serum control assayed on 10 days yielded CV’s of 4.6, 9.9, and 40.3% for 391, 45.3 and 1.9 U of isoenzymes MM, MB, and BB per liter, respectively. A reference interval for each isoenzymes was derived from data on 81 men and 63 women.
Restoration of lead-inhibited 5-aminolevulinate dehydratase activity in whole blood by heat, zinc ion, and (or) dithiothreitol.
Authors: Sakai T , Yanagihara S , Ushio K 
Published: February 2020

Abstract
We examined effects of heat, zinc, ion, and dithiothreitol in restoring the activity of lead-inhibited-5-aminolevulinate dehydratase (EC 4.2.1.24). The ratio of non-activated to activated activity produced by dithiothreitol correlated well with blood lead concentration among 35 lead workers. The individual effects of heat, zinc, or dithiothreitol differ from each other in the shift of pH optimum as well as in the extent to which activity is restored. Dual or triple combinations of these agents show additive or complementary restoration of activity. The combination of heat and zinc or zinc and dithiothreitol expands the range of optimum concentration of zinc in restoring activity. Using these combinations of agents, we can expect more accurate evaluation of lead exposure than by measuring only activation of zinc. Although dithiothreitol most powerfully restores activity, it restores not only the activity inhibited by lead exposure but also the activity removed by oxidation of SH-groups in the enzyme molecule.
Interferences appearing in fluorometrically measured liquid-chromatographic profiles of creatine kinase isoenzymes in serum.
Authors: Schlabach T D , Fulton J A , Mockridge P B , Toren E C 
Published: February 2020

Abstract
We observed nonenzymic peaks when serum isoenzymes of lactate dehydrogenase (EC 1.1.1.27; LD) and creatine kinase (EC 2.7.3.2.; CK) were separated by “high-performance” liquid chromatography and detected by continuously monitoring the column effluent for enzyme activity. Such background peaks were particularly apparent in CK isoenzyme profiles obtained from human sera. We observed two nonenzymic peaks with fluorescence detection, one in the CK-MB region, the other in the CK-BB region. Serum albumin was a major component in the artifactual CK-MB peak, with lipoprotein as a minor component. We present evidence that the material responsible for the other peak fluoresced quite strongly and is mostly pre-albumin.
Variability in the adsorption properties of microtitre plates used as solid supports in enzyme immunoassay.
Authors: Kricka L J , Carter T J , Burt S M , Kennedy J H , Holder R L , Halliday M I , Telford M E , Wisdom G B 
Published: February 2020

Abstract
We evaluated the variability in the amount of protein adsorbed onto the surface of individual wells of an assortment of microtitre plates by use of procedures involving enzyme-protein conjugates. Coefficients of variation in adsorbed protein ranged from 5.2 to 29.5%. Microtitre plates show a distinct “edge effect”; wells at the edges of a plate adsorb more protein than those in the interior, which markedly affects results from immunoassays involving such plates. In a sandwich enzyme immunoassay the results for an individual sample varied by +/− 18%; in a competitive assay, values read from different calibration curves in the same plate varied by +/− 11%. Scanning electron microscopy and birefringence studies demonstrated no marked physical differences between individual wells on a plate. The variability in the amount of protein adsorbed onto the surface of individual wells on the same microtitre plate seriously affects the reliability and interpretation of results of immunoassays in which such plates are used as solid supports.
Carcinoembryonic antigen assayed by column chromatography on polyacrylamide gel.
Authors: Weissman E B 
Published: February 2020

Abstract
I evaluated a commercially available polyacrylamide column (Clinetics Corp.) for use in assaying for carcinoembryonic antigen. The procedure eliminates the need for dialysis and 50 samples, assayed in duplicate, may be completed in 5 h. In general, results by this technique are 1.0 microgram/L (range 0.5-2.0) lower than by the conventional dialysis method (r = 0.9876). Sensitivity approximates 0.5 microgram/L. Within-day precision for two pools of patients’ plasma (n = 10) was mean = 2.29 (SEM 0.05) microgram/L with CV = 6.55% and mean = 10.61 (SEM 0.10) microgram/L with CV = 2.92%, respectively; between-day precision (n = 6) was mean = 3.90 (SEM 0.16) microgram/L with CV = 10.0% and mean = 10.1 (SEM 0.37) microgram/L, CV = 8.91%, respectively. The precentage analytical recovery of added carcinoembryonic antigen was about 80% at concentrations of approximately 8 and 12 microgram/L, 73% at 18 microgram/L.
A coupled-enzyme equilibrium method for measuring urea in serum: optimization and evaluation of the AACC study group on urea candidate reference method.
Authors: Sampson E J , Baird M A , Burtis C A , Smith E M , Witte D L , Bayse D D 
Published: February 2020

Abstract
We describe a coupled-enzyme equilibrium method for measuring urea in serum, which is performed on supernates prepared by treating each specimen with Ba(OH)2 and ZnSO4 (Somogyi reagent). Analytical recovery of [14C]urea added to a variety of matrices was essentially complete (mean, 100.6%) for the supernates after precipitation. Nine variables were univariately examined in arriving at the reaction conditions for the method: glutamate dehydrogenase, urease, 2-oxoglutarate, ADP, Tris . HCI, NADH, EDTA, pH, and temperature. The reagent is stable for at least 48 days at--20 degrees C and for 23 days at 4 degrees C. Mean analytical recovery of urea (14 mmol/L) added to seven different specimens (three different matrices) was 100.8%. The analytical linear range of the method extends to 30 mmol of urea per liter. Of 22 potential interferents, only bilirubin at 1 mmol/L (580 mg/L), hemoglobin at 10 g/L, and hydroxyurea at 6 mmol/L showed more than 2% interference. We discuss precision and effects of specimen dilution, and compare results for 100 human serum specimens with those measured for the same specimens with four other urea methods. We examined the effects of measuring a blank, consisting of sample and reagent without urease, with each specimen.
Liquid-chromatographic method for simultaneous determination of phenytoin and 5-(4-hydroxyphenyl)-5-phenylhydantoin in plasma and urine.
Authors: Sawchuk R J , Cartier L L 
Published: February 2020

Abstract
We describe a liquid-chromatographic assay for phenytoin and its para-hydroxylated metabolite, 5-(4-hydroxyphenyl)-5-phenylhydantoin, in plasma and urine. Unlike previously reported methods, this procedure is sensitive enough to allow quantitation of the unconjugated metabolite in plasma at concentrations observed clinically (50-500 microgram/L). Simultaneous measurements of the drug and its metabolite in plasma and urine may be helpful in explaining changes in the apparent clearance of phenytoin, assumed to occur through its metabolite. The method may also be used, without modification, for analysis for phenobarbital and carbamazepine in plasma. The accuracy of our method for these three drugs was assessed for 25 months in quality-assurance program for determining drug concentrations. Regression slopes for measured vs reported values for phenytoin, phenobarbital, and carbamazepine were 1.02, 0.99, and 0.99, respectively.
Creatine kinase radioimmunoassay and isoenzyme electrophoresis compared in the diagnosis of acute myocardial infarction.
Authors: Homburger H A , Jacob G L 
Published: February 2020

Abstract
We compared, in 116 patients, the relative usefulness of results of tests for creatine kinase B isoenzymes, as measured by radioimmunoassay, and the MB isoenzyme, as measured by electrophoresis, in diagnosis of acute myocardial infarction. The radioimmunoassay was specific for isoenzymes of creatine kinase containing the B subunit. All patients with acute transmural infarcts had positive test results by both techniques, but concentrations of B-isoenzymes were more frequently above normal than were MB bands in the case of patients with acute subendocardial infarcts and in the case of all patients with acute myocardial infarcts from whom sera were collected more than 24 h after onset of chest pain. Concentrations of B-isoenzymes also were increased, even when MB bands were not electrophoretically detectable, in specimens from several patients without documented actue myocardial infarcts. These abnormal results presumably were caused by increased concentrations of the BB isoenzyme in serum. Accordingly, an increased concentration of B-isoenzymes had less diagnostic specificity and predictive value for acute myocardial infarction than did a detectable MB band. Results of isoenzyme electrophoresis were more reliable for establishing this diagnosis, but the results of radioimmunoassay were more reliable for excluding it in patients with chest pain as the primary symptom.
Current results of left ventricular assist device therapy in France: the ASSIST-ICD registry
Authors: Anselmi Amedeo , Galand Vincent , Vincentelli André , Boule Stéphane , Dambrin Camille , Delmas Clément , Barandon Laurent , Pernot Mathieu , Kindo Michel , Tam Hoang Minh , Gaudard Philippe , Rouviere Philippe , Senage Thomas , Michel Magali , Boignard Aude , Chavanon Olivier , Verdonk Constance , Para Marylou , Gariboldi Vlad , Pelce Edeline , Pozzi Matteo , Obadia Jean-François , Anselme Frederic , Litzler Pierre-Yves , Babatasi Gerard , Belin Annette , Garnier Fabien , Bielefeld Marie , Guihaire Julien , Kloeckner Martin , Radu Costin , Lellouche Nicolas , Bourguignon Thierry , Genet Thibaud , D’Ostrevy Nicolas , Duband Benjamin , Jouan Jerome , Bories Marie Cécile , Vanhuyse Fabrice , Blangy Hugues , Colas Fabrice , Verhoye Jean-Philippe , Martins Raphael , Flecher Erwan 
Published: February 2020

Abstract

OBJECTIVES
Our goal was to provide a picture of left ventricular assist device (LVAD) activity in France between 2007 and 2016 based on the multicentric ASSIST-ICD registry.

METHODS
We retrospectively collected 136 variables including in-hospital data, follow-up survival rates and adverse events from 671 LVAD recipients at 20 out of 24 LVAD implant centres in France. The average follow-up time was 1.2 years (standard deviation: 1.4); the total follow-up time was 807.5 patient-years.

RESULTS
The included devices were the HeartMate II®, HeartWare LVAS® or Jarvik 2000®. The overall likelihood of being alive while on LVAD support or having a transplant (primary end point) at 1, 2, 3 and 5 years postimplantation was 65.2%, 59.7%, 55.9% and 47.7%, respectively, given a cumulative incidence of 29.2% of receiving a transplant at year 5. At implantation, 21.5% of patients were on extracorporeal life support. The overall rate of cardiogenic shock at implantation was 53%. The major complications were driveline infection (26.1%), pump pocket or cannula infection (12.6%), LVAD thrombosis (12.2%), ischaemic (12.8%) or haemorrhagic stroke (5.4%; all strokes 18.2%), non-cerebral haemorrhage (9.1%) and LVAD exchange (5.2%). The primary end point (survival) was stratified by age at surgery and by the type of device used, with inference from baseline profiles. The primary end point combined with an absence of complications (secondary end point) was also stratified by device type.

CONCLUSIONS
The ASSIST-ICD registry provides a real-life picture of LVAD use in 20 of the 24 implant centres in France. Despite older average age and a higher proportion of patients chosen for destination therapy, survival rates improved compared to those in previous national registry results. This LVAD registry contrasts with other international registries because patients with implants have more severe disease, and the national policy for graft attribution is distinct. We recommend referring patients for LVAD earlier and suggest a discussion of the optimal timing of a transplant for bridged patients (more dismal results after the second year of support?).
Catheter ablation of arrhythmogenic right ventricular cardiomyopathy ventricular tachycardia: 18-year experience in 284 patients
Authors: Liang Erpeng , Wu Lingmin , Fan Siyang , Hu Feng , Zheng Lihui , Liu Shangyu , Fan Xiaohan , Chen Gang , Ding Ligang , Niu Guodong , Yao Yan 
Published: February 2020

Abstract

Aims
The study aims to describe the long-term outcome of radiofrequency catheter ablation for ventricular tachycardia (VT) in a large cohort arrhythmogenic right ventricular cardiomyopathy (ARVC) patients.

Methods and results
Radiofrequency catheter ablation was performed in 284 ARVC patients due to VT between July 2000 and January 2019. An endocardial approach was used initially, with epicardial ablation procedures reserved for those patients who failed an endocardial ablation. Activation, entrainment, pace and substrate mapping strategies were used with regional ablation applied. A total of 393 ablation procedures were performed including endocardial approach only (n = 377) and endo and epicardial combined (n = 16). Right ventricular basal free wall was accounted as the primary substrate of VT in 258 (65.6%) patients. There were 81 patients underwent redo ablation procedure (second time = 81; ≥3 times = 28). New targets were observed in 68.8% of redo procedures. There were 171 VT recurrences and 19 deaths occurred during the follow-up. Ventricular tachycardia-free survival rate of the first, second, and last ablation procedure was 56.7%, 73.2%, and 78.1%, respectively. Multivariate analysis showed ≥3 induced VTs in the procedure was correlated with rehospitalized VT recurrence [hazard ratio (HR) 1.467, 95% confidence interval (CI) 1.052–2.046; P = 0.024]. For all-cause mortality, rehospitalized VT and ≥3 induced VTs were the independent risk factors (HR 2.954, 95% CI 1.8068.038; P = 0.034; HR 3.189, 95% CI 1.073–9.482; P = 0.037).

Conclusion
Endocardial ablation is effective to ARVC VT though it may require repeated procedures. Induced multiple VTs was correlated with worse outcomes.
Baby Genomics: Tracing the Evolutionary Changes That Gave Rise to Placentation
Authors: Hao Yue , Lee Hyuk Jin , Baraboo Michael , Burch Katherine , Maurer Taylor , Somarelli Jason A , Conant Gavin C 
Published: February 2020

AbstractIt has long been challenging to uncover the molecular mechanisms behind striking morphological innovations such as mammalian pregnancy. We studied the power of a robust comparative orthology pipeline based on gene synteny to address such problems. We inferred orthology relations between human genes and genes from each of 43 other vertebrate genomes, resulting in ∼18,000 orthologous pairs for each genome comparison. By identifying genes that first appear coincident with origin of the placental mammals, we hypothesized that we would define a subset of the genome enriched for genes that played a role in placental evolution. We thus pinpointed orthologs that appeared before and after the divergence of eutherian mammals from marsupials. Reinforcing previous work, we found instead that much of the genetic toolkit of mammalian pregnancy evolved through the repurposing of preexisting genes to new roles. These genes acquired regulatory controls for their novel roles from a group of regulatory genes, many of which did in fact originate at the appearance of the eutherians. Thus, orthologs appearing at the origin of the eutherians are enriched in functions such as transcriptional regulation by Krüppel-associated box-zinc-finger proteins, innate immune responses, keratinization, and the melanoma-associated antigen protein class. Because the cellular mechanisms of invasive placentae are similar to those of metastatic cancers, we then used our orthology inferences to explore the association between placenta invasion and cancer metastasis. Again echoing previous work, we find that genes that are phylogenetically older are more likely to be implicated in cancer development.
The Country That Never Retires: The Gendered Pathways to Retirement in South Korea
Authors: Lee Yeonjin , Yeung Wei-Jun Jean 
Published: February 2020

Abstract

Objectives
Among all Organization for Economic Cooperation and Development countries, South Korean older adults work until the latest age. We investigate the extent to which work experiences over the life course and family circumstances can be associated with older workers’ incentives to remain in the labor force beyond the statutory pension age. We explore gender-specific patterns of labor force exit and labor force re-entry in later life.

Methods
Using panel data of South Korean older workers and retirees from 2006 to 2016, we estimate multilevel discrete-time models with random effects to predict their labor force transition process that unfolds over time.

Results
Results show that skilled manual workers are less likely to exit employment and more likely to re-enter the labor force. A longer history of self-employment is related to later retirement. The relationship between career characteristics and the risk of retirement is only significant for men. Late-aged employment transition among women appears to be more related to family conditions. Women who receive financial support from adult offspring are more likely to remain out of the labor force but this relationship is not pronounced among men.

Discussion
Policies aimed at extending working lives need to provide various types of social support to older job seekers, especially those who had low-class jobs and those without family networks.
Technology and Caregiving: Emerging Interventions and Directions for Research
Authors: Lindeman David A , Kim Katherine K , Gladstone Caroline , Apesoa-Varano Ester Carolina 
Published: February 2020

Abstract
An array of technology-based interventions has increasingly become available to support family caregivers, primarily focusing on health and well-being, social isolation, financial, and psychological support. More recently the emergence of new technologies such as mobile and cloud, robotics, connected sensors, virtual/augmented/mixed reality, voice, and the evermore ubiquitous tools supported by advanced data analytics, coupled with the integration of multiple technologies through platform solutions, have opened a new era of technology-enabled interventions that can empower and support family caregivers. This paper proposes a conceptual framework for identifying and addressing the challenges that may need to be overcome to effectively apply technology-enabled solutions for family caregivers. The paper identifies a number of challenges that either moderate or mediate the full use of technologies for the benefit of caregivers. The challenges include issues related to equity, inclusion, and access; ethical concerns related to privacy and security; political and regulatory factors affecting interoperability and lack of standards; inclusive/human-centric design and issues; and inherent economic and distribution channel difficulties. The paper concludes with a summary of research questions and issues that form a framework for global research priorities.
The Emerging Intersection Between Injection Drug Use and Early Syphilis in Nonurban Areas of Missouri, 2012–2018
Authors: Reno Hilary , Fox Branson , Highfill Craig , McKee Angela , Trolard Anne , Liang Stephen Y , Stoner Bradley P , Meyerson Beth E 
Published: February 2020

Abstract

Background
The national rate of syphilis has increased among persons who inject drugs (PWID). Missouri is no exception, with increases in early syphilis (ES), congenital syphilis, and PWID, especially in nonurban counties.

Methods
Disease intervention specialist records for ES cases in Missouri (2012–2018) were examined. Drug use was classified as injection drug use (IDU) (opioid or methamphetamine) or non-IDU (opioid, methamphetamine, or cocaine). Rates were compared based on residence, sex of sex partner, and drug use.

Results
Rates of ES in Missouri increased 365%, particularly in small metropolitan and rural areas (1170%). Nonurban areas reported a higher percentage of persons with ES who used injection drugs (12%–15%) compared with urban regions (2%–5%). From 2012 to 2018, women comprised an increasing number of ES cases (8.3%–21%); 93% of women were of childbearing age. Increasingly more women in rural areas with ES also reported IDU during this time (8.4%–21.1%).

Conclusions
As syphilis increases in small metropolitan and rural regions, access to high-quality and outreach-based sexual health services is imperative. Healthcare policy to equip health departments with harm reduction services and drug treatment resources offers an opportunity to impact both syphilis increases as well as health outcomes associated with IDU.