bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prostate-specific Antigen: A Cancer Fighter and a Valuable Messenger?
Authors: Diamandis Eleftherios P 
Published: January 2020

Abstract
Background: Prostate-specific antigen (PSA) is a valuable prostatic cancer biomarker that is now widely used for population screening, diagnosis, and monitoring of patients with prostate cancer. Despite the voluminous literature on this biomarker, relatively few reports have addressed the issue of its physiological function and its connection to the pathogenesis and progression of prostate and other cancers.
Approach: I here review literature dealing with PSA physiology and pathobiology and discuss reports that either suggest that PSA is a beneficial molecule with tumor suppressor activity or that PSA has deleterious effects in prostate, breast, and possibly other cancers.
Content: The present scientific literature on PSA physiology and pathobiology is confusing. A group of reports have suggested that PSA may act as a tumor suppressor, a negative regulator of cell growth, and an apoptotic molecule, whereas others suggest that PSA may, through its chymotrypsin-like activity, promote tumor progression and metastasis.
Summary: The physiological function of PSA is still not well understood. Because PSA is just one member of the human kallikrein gene family, it is possible that its biological functions are related to the activity of other related kallikreins. Only when the physiological functions of PSA and other kallikreins are elucidated will we be able to explain the currently apparently conflicting experimental data.
Prevention of in Vitro Lipolysis by Tetrahydrolipstatin
Authors: Krebs Michael , Stingl Harald , Nowotny Peter , Weghuber Daniel , Bischof Martin , Waldhäusl Werner , Roden Michael 
Published: January 2020

AbstractBackground: Metabolic effects of free fatty acids (FFAs) frequently are tested using combined infusion of triglycerides and heparin, which stimulates lipolysis in vivo. Ongoing in vitro lipolysis, however, probably produces falsely high plasma FFA concentrations under these conditions. Therefore, this study aims to assess the efficacy of tetrahydrolipstatin (THL) in inhibiting plasma lipolytic activity and to improve plasma FFA determination.Methods: Plasma concentrations of FFAs and glycerol were measured in five healthy subjects in the presence and absence of THL. Blood was drawn at baseline, during infusion of a triglyceride emulsion (1.5 mL/min), and during infusion of triglycerides plus heparin (0.2 IU · kg−1 · min−1). In addition, the effects of storage temperature of the samples were analyzed.Results: In samples frozen immediately after collection, plasma FFAs were 28% lower in the presence of THL than in its absence (P = 0.008). When THL-free plasma was incubated for 3 h on ice or at room temperature, plasma FFAs were 22% (P = 0.02) and 91% (P = 0.0004) higher, respectively, than in samples frozen immediately. The addition of THL blunted temperature-dependent in vitro lipolysis by 88% (P &lt;0.01) and 89% (P &lt;0.001) after incubation on ice and at room temperature, respectively. Changes in plasma glycerol concentrations exhibited similar behavior.Conclusions: THL, which is safe and easy to handle, is a potent inhibitor of in vitro lipolysis and could, therefore, be added to blood samples drawn during triglyceride/heparin infusions to allow more accurate determination of plasma FFA concentrations.
Genotyping of Factor V G1691A (Leiden) without the Use of PCR by Invasive Cleavage of Oligonucleotide Probes
Authors: Hessner Martin J , Budish Mary Ann , Friedman Kenneth D 
Published: January 2020

Abstract
Background: The factor V G1691A Leiden (FVL) mutation is the most common known hereditary risk factor for venous thrombosis.
Methods: Third Wave Technologies, Inc. (Madison, WI) has developed a new microtiter plate-based assay that does not require PCR, restriction digestion, or gel electrophoresis. This technology system, termed the InvaderTM assay, utilizes a 5′ “invading” oligonucleotide and a partially overlapping 3′ “signal” oligonucleotide, which together form a specific structure when bound to a complementary genomic DNA template. A thermostable flap endonuclease cleaves this structure, releasing the 5′ flap from the signal oligonucleotide. Increased temperature and an excess of the signal probe enable multiple probes to be cleaved for each target sequence present without temperature cycling. The cleaved probes then direct cleavage of a secondary probe, which is 5′ end-labeled with fluorescein but is quenched by an internal dye. Upon cleavage, the fluorescein-labeled product is detected using a standard fluorescence plate reader. Genotypes are determined by net wild-type/mutant signal ratio.
Results: Complete concordance was observed, after resolution of four discordances, when 1369 individuals (1264 wild type, 102 heterozygous, 3 homozygous) were FVL genotyped by both the Invader assay and by allele-specific PCR.
Conclusion: We conclude that FVL genotyping using invasive cleavage of oligonucleotide probes is a rapid and reliable alternative to genotyping by more traditional PCR-based methods.
Genetic Analysis of DNA Excreted in Urine: A New Approach for Detecting Specific Genomic DNA Sequences from Cells Dying in an Organism
Authors: Botezatu Irina , Serdyuk Ol’ga , Potapova Galina , Shelepov Valery , Alechina Raisa , Molyaka Yuriy , Anan’ev Vitaliy , Bazin Igor , Garin August , Narimanov Mehti , Knysh Vasiliy , Melkonyan Hovsep , Umansky Samuil , Lichtenstein Anatoly 
Published: January 2020

Abstract
Background: Cell-free DNA from dying cells recently has been discovered in human blood plasma. In experiments performed on animals and humans, we examined whether this cell-free DNA can cross the kidney barrier and be used as a diagnostic tool.
Methods: Mice received subcutaneous injections of either human Raji cells or purified 32P-labeled DNA. DNA was isolated from urine and analyzed by measurement of radioactivity, agarose gel electrophoresis, and PCR. In humans, the permeability of the kidney barrier to polymeric DNA was assessed by detection in urine of sequences that were different from an organism bulk nuclear DNA.
Results: In the experiments on laboratory animals, we found that ∼0.06% of injected DNA was excreted into urine within 3 days in a polymeric form and that human-specific Alu sequences that passed through the kidneys could be amplified by PCR. In humans, male-specific sequences could be detected in the urine of females who had been transfused with male blood as well as in DNA isolated from urine of women pregnant with male fetuses. K-ras mutations were detected in the urine of patients with colon adenocarcinomas and pancreatic carcinomas.
Conclusions: The data suggest that the kidney barrier in rodents and humans is permeable to DNA molecules large enough to be analyzed by standard genetic methodologies.
Opportunistic Discovery of Occult Disease by Use of Test Panels in New, Symptomatic Primary Care Outpatients: Yield and Cost of Case Finding
Authors: Takemura Yuzuru , Ishida Haku , Inoue Yuji , Kobayashi Hiroyuki , Beck J Robert 
Published: January 2020

Abstract
Background: Diagnostic test panels have been advocated by the Japan Society of Clinical Pathology for evaluation of presenting complaints of new outpatients in primary care medicine. The tests have additional potential utility for opportunistic finding of asymptomatic diseases, but data are lacking on the number of new conditions identified by the test panels and on the cost per identified case.
Methods: We studied 540 new, symptomatic patients at the Comprehensive Medicine Clinics of National Defense Medical College during 1991–1997. All underwent testing with the “Essential Laboratory Tests” panel (2) [ELT(2) panel]. This panel includes hematologic tests, urinalysis, total protein, C-reactive protein, albumin, cholesterol, triglycerides, glucose, urea nitrogen, creatinine, uric acid, serum protein fractionation, six enzymes, and optional tests, including x-rays, electrocardiogram, and fecal occult blood.
Results: The ELT(2) panel uncovered 276 additional diagnoses of asymptomatic disease or abnormal health status. The most frequent occult condition was hyperlipidemia (100 cases) followed by liver dysfunction (53 cases). Clinical efficiency of the panel (occult diseases/patient) varied depending on the category of tentative initial diagnosis, with the highest efficiency in patients with cardiovascular disease. We created smaller panels by combining 11 basic tests [called the ELT(1) baseline panel] with one or more additional tests from the ELT(2) and analyzed their cost-effectiveness. Addition of four tests (total cholesterol, alanine aminotransferase, glucose, and uric acid) improved both clinical efficiency (0.41 occult disease/patient) and economic efficiency [¥2372 (∼$22.50 US)/occult disease] at a cost-effectiveness of ¥177 per incremental case of occult disease. Addition of further tests decreased cost-effectiveness.
Conclusions: Although the ELT(2) panel has supplemental utility for opportunistic screening of some significant, occult diseases and conditions, universal utilization of the full panel is not supported by the cost-effectiveness found in this study.
Quantification and Characterization of Pregnancy-associated Complexes of Angiotensinogen and the Proform of Eosinophil Major Basic Protein in Serum and Amniotic Fluid
Authors: Christiansen Michael , Jaliashvili Irakli , Overgaard Michael T , Ensinger Christian , Obrist Peter , Oxvig Claus 
Published: January 2020

AbstractBackground: The proform of eosinophil major basic protein (ProMBP) exists in serum from pregnant women complexed with a variable fraction of angiotensinogen (Ang). A subfraction further binds complement C3dg in a 2:2:2 complex. The function, physiology, and clinical importance of ProMBP complexes are unknown, and the specific quantification of these complexes has not been possible.Methods: We developed an ELISA for the ProMBP/Ang complexes, using a monoclonal antibody against ProMBP for capture and a chicken anti-human Ang antiserum for detection. Calibrators were standardized with WHO IRP 78/610 for pregnancy proteins in the assay range 0.95–15.6 mIU/L.Results: The concentrations of ProMBP/Ang complexes in serum of nonpregnant blood donors (n = 79) were log-normally distributed with a central 95th interval of 985-3655 mIU/L. In pregnancy, mean serum concentrations were increased from week 7, and the concentrations reached term concentrations in week 18. ProMBP/Ang complexes eluted in gel filtration as a broad peak with a molecular mass of ∼230 kDa. The concentration of ProMBP/Ang/C3dg increased during blood coagulation, suggesting that the ProMBP/Ang/C3dg complex may be a marker of complement activation.Conclusions: ProMBP/Ang complexes are present in serum from nonpregnant persons as well as pregnant women, and the direct assays described here will make it possible to study the biochemistry and the clinical significance of different ProMBP complexes in pathological conditions and pregnancy.
Evidence-based Implementation of Free Phenytoin Therapeutic Drug Monitoring
Authors: Burt Martha , Anderson David C , Kloss Julie , Apple Fred S 
Published: January 2020

AbstractBackground: The majority of laboratories measure total phenytoin concentration for therapeutic drug monitoring. However, there are substantial interindividual variations in free phenytoin concentrations, the pharmacologically active component.Methods: We describe the process and data used to implement monitoring of free phenytoin only in an urban medical center. Over a 6-week period, total and free phenytoin concentrations were measured, clinical charts reviewed, and indications for alterations in the percentage of free phenytoin fraction were determined.Results: Of the 189 phenytoin requests from 139 patients, 136 data points were analyzed. Free phenytoin concentrations were 6.8–35.3%, with 50% outside the expected range of 8–12%. Clinical indications likely responsible for variations were hypoalbuminemia, drug interactions, uremia, pregnancy, and age. Overall, 30% of patients demonstrated a discrepancy between therapeutic, subtherapeutic, or supratherapeutic concentrations between free and total phenytoin concentrations. The largest discordance (53%) occurred in the patient group with free phenytoin &lt;8% or &gt;12%.Conclusions: This study supports previous clinical findings that monitoring total phenytoin is not as reliable as free phenytoin as a clinical indicator for therapeutic and nontherapeutic concentrations. Thus, we recommend that therapeutic monitoring should use free phenytoin concentrations only.
Bone Lead Concentrations Assessed by in Vivo X-Ray Fluorescence
Authors: Ambrose Theresa M , Al-Lozi Muhammad , Scott Mitchell G 
Published: January 2020

Abstract
The assessment of past chronic lead exposure is difficult. Chronic lead burden is not always correctly assessed using laboratory-based tests that are useful for acute or recent exposures. We describe a case of suspected chronic lead exposure that illustrated the need for improved and possibly noninvasive methods to determine cumulative lead body burden. X-Ray fluorescence (XRF) is discussed as a method to obtain in vivo bone lead measurements. We discuss the potential of such measurements as accurate biomarkers of cumulative exposure and whether XRF can be used for retroactive exposure assessment or to predict risk of future health problems.
Understanding and Identifying Monoclonal Gammopathies
Authors: Attaelmannan Mohammed , Levinson Stanley S 
Published: January 2020

AbstractMonoclonal gammopathies reflect conditions in which abnormal amounts of immunoglobulins are produced by a clone that developed from a single pro-B germ cell. The condition may reflect a disease process or be benign. The primary purpose of this review is to emphasize routine clinical laboratory techniques that currently are recommended for use in identifying monoclonal gammopathies from serum and urine. Selection of the preferred technique and correct interpretation often is dependent on an understanding of the immunological basis and clinical sequelae associated with these conditions. For this reason, we first briefly discuss the structure, production, and nature of immunoglobulins, and then describe important features of the associated diseases. Finally, we discuss strengths and weaknesses of the techniques and make reference to current recommendations to facilitate optimal testing. We discuss in detail high-resolution electrophoresis, methods for quantifying immunoglobulins, immunofixation electrophoresis, problems associated with analysis of urine immunoglobulins, and identification of cryoglobulins and immune complexes.
Multifaceted Approach to the Diagnosis and Classification of Acute Leukemias
Authors: McKenna Robert W 
Published: January 2020

AbstractUntil recently, the diagnosis and classification of acute myeloid (AML) and acute lymphoblastic (ALL) leukemias was based almost exclusively on well-defined morphologic criteria and cytochemical stains. Although most cases can be diagnosed by these methods, there is only modest correlation between morphologic categories and treatment responsiveness and prognosis. The expansion of therapeutic options and improvement in remission induction and disease-free survival for both AML and ALL have stimulated emphasis on defining good and poor treatment response groups. This is most effectively accomplished by a multifaceted approach to diagnosis and classification using immunophenotyping, cytogenetics, and molecular analysis in addition to the traditional methods. Immunophenotyping is important in characterizing morphologically poorly differentiated acute leukemias and in defining prognostic categories of ALL. Cytogenetic and molecular studies provide important prognostic information and are becoming vitally important in determining the appropriate treatment protocol. With optimal application of these techniques in the diagnosis of acute leukemias, treatment strategies can be more specifically directed and new therapeutic approaches can be evaluated more effectively.
Cardiac Troponin T and I in End-Stage Renal Failure
Authors: Wayand Diana , Baum Hannsjörg , Schätzle Gabriele , Schärf Julia , Neumeier Dieter 
Published: January 2020

AbstractBackground: In patients suffering from end-stage renal failure, cardiac troponin T (cTnT) and I (cTnI) may be increased in serum without other signs of acute myocardial damage. Whether these increases are specific to myocardial injury or nonspecific is not completely clear.Methods: We investigated time courses of cTnT and cTnI over 1 year and the clinical outcome over 2 years in 59 patients with end-stage renal failure undergoing chronic hemodialysis. At the start of the study, we divided the patients into two groups, group 1, without history of cardiac failure, and group 2, with history of cardiac failure, and looked for differences between the groups in later adverse outcome. cTnT was measured using the Enzymun® troponin T assay on an ES 700 analyzer (Roche). cTnI was measured on a Stratus® II analyzer (Dade Behring). Creatinine and blood urea nitrogen were measured on a Vitros® 950 IRC (Ortho).Results: Dialysis acutely increased cTnT (P &lt;0.01) and decreased cTnI (P &lt;0.001) regardless of the dialysis membrane used. Although statistically not significant, cTnT but not cTnI was increased more frequently in group 2 than in group 1, in some cases over the whole study period. Five patients (8.5%) died of cardiac complications within 2 years; all of them had mostly increased cTnT and, in one or more samples, increased cTnI.Conclusions: Dialysis alters measured cTnT and cTnI concentrations in serum. In patients suffering from end-stage renal failure, sporadic or persistently increased cTnT and cTnI appear to predict cardiac complications. Because of the effects of the dialysis procedure on troponin values, we recommend that blood be collected before dialysis.
Determination of Total Interleukin-8 in Whole Blood after Cell Lysis
Authors: Reinsberg Jochen , Dembinski Jörg , Dorn Christoph , Behrendt Daniela , Bartmann Peter , van der Ven Hans 
Published: January 2020

AbstractBackground: It has been shown that a high percentage of interleukin-8 (IL-8) in blood is cell associated. Recently, a simple method for determination of cell-associated IL-8 in whole blood after cell lysis has been described. The purpose of this study was to evaluate this method, to examine the influence of preanalytic sample handling, and to establish the concentration range of total IL-8 and its relation to age and sex in healthy subjects.Methods: Total IL-8 content of whole blood was determined after lysing blood cells with Milenia® cell lysis solution. IL-8 in the resulting blood lysate was measured with the IMMULITE® IL-8 immunoassay.Results: When freshly drawn blood was stored up to 48 h on ice, no significant changes in total IL-8 were measured in the subsequently prepared lysate, whereas with storage at room temperature, total IL-8 increased after 3 h from 94 ± 13 ng/L to 114 ± 16 ng/L (n = 10). In lysate stored for 48 h at 4 °C, marginal changes of the IL-8 concentration were noted, with storage at room temperature, only 76% ± 5% (n = 12) of initial concentration was recovered. From lysate frozen at −20 and −80 °C, respectively, 84% ± 4% and 93% ± 2% of initial IL-8 was recovered after 70 days (n = 10). IL-8 was measured with comparable precision in plasma (CV, 3.2–4.2%) and blood lysate (CV, 3.7–4.1%). When plasma was diluted with cell lysis solution, a slightly overestimated recovery (125% ± 3%) was observed; for lysate specimens with a cell lysis solution content ≥75%, the recovery after dilution was 98% ± 2%. In lysate prepared from 12 blood samples with exogenous IL-8 added, IL-8 recovery was 104% ± 2% (recovery from plasma &lt;35%). The median total IL-8 in blood lysates from 103 healthy subjects (22–61 years) was 83 ng/L of blood (2.5–97.5 percentile range, 49–202 ng/L of blood). In females but not in males, total IL-8 increased significantly with advancing age (P &lt;0.002). We found grossly increased total IL-8 in six pregnant women with amniotic infection syndrome.Conclusions: The evaluated method allows the assessment of total IL-8 in blood with good performance when appropriate conditions of sample pretreatment are considered. The values in healthy volunteers all were above the detection limit of the IL-8 assay; therefore, slight changes of total IL-8 could be noted. Thus, the present method is a suitable tool to study the diagnostic relevance of total IL-8 in blood.
Genetic Algorithm for Scheduling of Laboratory Personnel
Authors: Boyd James C , Savory John 
Published: January 2020

Abstract
Background: Staffing core laboratories with appropriate skilled workers requires a process to schedule these individuals so that all workstations are appropriately filled and all the skills of each worker are exercised periodically to maintain competence.
Methods: We applied a genetic algorithm to scheduling laboratory personnel. Our program, developed in Visual Basic 4.0, maximizes the value of a fitness function that measures how well a given scheduling of individuals and their skills matches a set of work tasks for a given work shift. The user provides in an Excel spreadsheet the work tasks, individuals available to work on any given date, and skills each individual possesses. The user also specifies the work shift to be scheduled, the range of dates to be scheduled, the number of days that an individual stays on a given workstation before rotating, and various parameters for the genetic algorithm if they differ from the default values.
Results: For &gt;22 months, the program matched individuals to those tasks for which they were qualified and maintained personnel skills by rotating job duties. The schedules generated by the program allowed supervisory personnel to anticipate dates far in advance of when worker availability would be limited, so staffing could be adjusted. In addition, the program helped to identify skills for which too few individuals had been trained. This program has been well accepted by the staff in the clinical laboratories of a 670-bed university medical center, saving 37 h of labor per month, or approximately $11 000 per year, in time that supervisory personnel have spent developing work schedules.
Conclusions: The genetic algorithm approach appears to be useful for scheduling in highly technical work environments that employ multiskilled workers.
Comparison of HPLC and Small Column (CDTect) Methods for Disialotransferrin
Authors: Turpeinen Ursula , Methuen Taina , Alfthan Henrik , Laitinen Kalevi , Salaspuro Mikko , Stenman Ulf-Håkan 
Published: January 2020

AbstractBackground: Current methods for determination of carbohydrate-deficient transferrin (CDT) are based on separation of the CDT fraction by ion-exchange chromatography on minicolumns and quantification by immunoassay. Alternatively, the transferrin isoforms can be separated by HPLC anion-exchange chromatography and quantified by absorbance. This method has been reported to improve the validity of CDT as a marker of chronic alcohol abuse.Methods: HPLC on either MonoQ or ResourceQ anion-exchange columns was used to separate and quantify isoforms of transferrin with detection at 460 nm. The result was expressed as the percentage of the disialo form (pI 5.7) of total transferrin (DST). The commercial CDTectTM assay was used as a comparison method. Serum samples from nondrinkers (n = 57), moderate drinkers (n = 77), and heavy drinkers (n = 139) were analyzed.Results: In ROC analysis for differentiation between moderate and heavy drinkers, the area under the curve (AUC) for the HPLC method was 0.87 (95% confidence interval, 0.81–0.93), whereas that for CDTect was 0.72 (95% confidence interval, 0.64–0.80). At 90% specificity, the sensitivity of DST was 63% (95% confidence interval, 53–73%) compared with 33% (22–44%) for CDT. The reference interval of the HPLC method was 0.68–1.7%.Conclusions: The HPLC anion-exchange method for quantification of CDT provides substantially better separation between moderate and heavy drinkers than the CDTect method.