bluuebunny/crossref_metadata_2025_split huggingface dataset:
Benefits and risks of emerging genetic technologies: the need for regulation
Authors: Holtzman N A 
Published: January 2020

Abstract
Efforts to localize human genes to specific chromosomes and then to identify these genes and their role in specific diseases are increasing. These developments will expand the repertoire of genetic tests that are claimed to be predictive of future disease in the person being tested (pre-symptomatic tests) or in future offspring of those being tested (tests for reproductive options). In single-gene (mendelian) disorders, such tests may fail to detect all of the alleles capable of causing disease. In multifactorial disorders, positive results of tests for specific alleles will not always predict future disease because the other necessary factors may be absent. Policies are already in place to provide safe and effective clinical laboratory tests and interventions for subjects with positive test results, and to assure the quality of the laboratories performing such tests, but are not widely known or enforced for genetic tests.
Use of small-sample-based reference limits on a group basis
Authors: van der Meulen E A , Boogaard P J , van Sittert N J 
Published: January 2020

Abstract
The evaluation of a biochemical or hematological quantity measured in a study group of employees during occupational health assessments involves a comparison with a reference sample group. Part of this evaluation consists of checking whether the percentage of values larger than a predetermined upper reference limit is significantly larger than the percentage normally expected (2.5%, if the 97.5 percentile is used as the upper reference limit). The reference limit, however, is estimated from a random reference sample, the size of which, for many reasons, may be relatively small; as a consequence, the reference limit estimate will be imprecise. In situations in which the reference sample size is smaller than or not much larger than the study sample size, this imprecision results in the usual binomial test of significance being highly inappropriate. We provide an exact nonparametric test valid for all reference sample sizes.
Molecular diagnosis of acute intermittent porphyria by analysis of DNA extracted from hair roots
Authors: Schreiber W E , Fong F , Jamani A 
Published: January 2020

Abstract
Analysis for mutations in the porphobilinogen deaminase gene offers a more definitive diagnosis of acute intermittent porphyria (AIP) than do conventional biochemical tests. We used single-strand conformation polymorphism analysis followed by direct sequencing to identify a new G--&gt;A mutation at the last position of intron 7 in a patient with AIP. The mutation disrupts the invariant AG dinucleotide at the 3' splice acceptor site and therefore interferes with mRNA processing. To identify other individuals who inherited this mutation, we analyzed five hairs with intact roots collected by each participating family member and sent to us by mail. DNA was extracted from the hair roots and amplified by the polymerase chain reaction. The amplified products were digested with the restriction enzyme BsaJI to confirm the presence or absence of the mutation. All six family members who were known to have AIP tested positive, as did three members who had not been previously diagnosed. Hair roots provide a convenient, accessible, and economical alternative to blood as a source of DNA for molecular diagnostic testing.
Micromachined analyzers on a silicon chip
Authors: Arquint P , Koudelka-Hep M , van der Schoot B H , van der Wal P , de Rooij N F 
Published: January 2020

Abstract
For an example of a silicon-based micromachined analyzer, we describe a combined PO2, PCO2, and pH sensor designed for extracorporeal blood gas monitoring. The clinically well-accepted amperometric (PO2) and potentiometric (PCO2, pH) sensing principles are used, realized in a planar and miniaturized form on a single silicon chip (6 x 22 mm). The transducer part of the chip is fabricated by standard silicon technology. Polyacrylamide and polysiloxane polymeric layers, which are used as internal electrolyte and gas-permeable membrane, respectively, are deposited and patterned by photopolymerization. The entire sensor is fabricated on the wafer level by using integrated-circuit-compatible processes, thus allowing mass production. By integrating a flow-through channel directly on the chip, the sample size and the reagent consumption are substantially reduced. The device was characterized in aqueous solutions and in blood intended for transfusion. The sensor has a typical sensitivity of 0.36 nA/mmHg (PO2), -39 mV/decade (PCO2), and 51 mV/pH (pH); low drift; and a functional lifetime of &gt; 2 months. The analytical precision in the physiologically expected range is better than 2 mmHg for the PO2 and PCO2 sensor, and 0.02 pH unit for the pH sensor.
Improvements to immunoassays by use of covalent binding assay plates
Authors: Douglas A S , Monteith C A 
Published: January 2020

Abstract
The uniformity of Xenobind covalent binding microwell plates was compared with that of passive binding plates by binding streptavidin to the plate surface, reacting the streptavidin with biotinylated alkaline phosphatase, and developing color with phenolphthalein monophosphate. Absorbance of the covalent binding plates at 570 nm was 0.95 A (CV 1.9%) compared with 0.35-0.5 A (CV 6.7-16.9%), for passive plates. No edge effect was observed with Xenobind covalent plates. Use of both plates in a model immunoassay gave a CV of 4% for the covalent binding plate and 12-15% for the passive binding plates. Moreover, the background absorbance (color development when no antigen was present) for the covalent binding plates was &lt; 0.05 A in all cases, whereas that for the passive binding plates ranged up to 0.45 A. The high background on passive plates results from displacement of capture antibody and (or) blocking agent from the plate, thereby providing a place for detector antibody binding.
Natural history and risk factors for early human atherogenesis. Pathobiological Determinants of Atherosclerosis in Youth (PDAY) Research Group
Authors: Strong J P 
Published: January 2020

Abstract
A multi-institutional study, Pathobiological Determinants of Atherosclerosis in Youth (PDAY), was initiated to document the natural history of atherosclerosis, its relationship to risk factors, and the pathobiology of lesion development in young subjects. Pathology laboratories in nine centers collected arteries and tissues from &gt; 2000 persons, ages 15-34 years, whose deaths were attributed to homicides, accidents, or suicides. Arteries were evaluated for lesions, and risk factors were analyzed in a central laboratory. Postmortem risk factors include serum lipoproteins, serum thiocyanate (smoking), glycohemoglobin (diabetes), thickness of panniculus adiposus (obesity), changes in small renal arteries (hypertension), and apoprotein isoforms. This PDAY study documents the development of atherosclerosis at an early age and shows that the recognized risk factors for coronary heart disease are associated with lesion development in the arteries of these young subjects. The findings provide a strong justification for reducing risk factors in young persons.
Rapid, automated quantification of total human chorionic gonadotropin in serum by a chemiluminescent enzyme immunometric assay
Authors: Vankrieken L , De Hertogh R 
Published: January 2020

Abstract
Total human chorionic gonadotropin (hCG-hCG beta) in serum was assayed with the immulite system, a fully automated random-access immunoassay analyzer that has a unique centrifugal procedure for solid-phase washing and a chemiluminescent detection system. The broad range of the hCG calibration curve (up to 5000 IU/L) is achieved by using a small serum sample size (5 microL), which provides sufficient volume for low-end sensitivity and prevents the possible high-dose hook effect in the working range of the assay. Within-run imprecision (CV) ranged from 3.9% to 5.9% for hCG between 10.5 and 2908 IU/L. Between-run imprecision ranged from 8.8% to 12.7% for hCG mean concentrations from 11.4 to 88.4 IU/L. The antibodies used in the immulite hCG assay system gave little or no interferences when high amounts of follitropin, lutropin, and thyrotropin were added. A complete recognition of the free beta-subunit of hCG was obtained (+/- 180%). In sera from women with molar pregnancies, we observed no high-dose hook effect at hCG concentrations up to 3000 kIU/L. The broad range of hCG concentrations encountered throughout normal pregnancy (up to 200 kIU/L) requires an extended working range to avoid high dilutions. In early pregnancy, accuracy in the range of 1000-5000 IU/L is enhanced by avoiding dilutions.
Can molecular markers now be used for early diagnosis of malignancy?
Authors: Duffy M J 
Published: January 2020

Abstract
Most of the presently available cancer markers are neither specific for malignancy nor allow early diagnosis. However, the recent elucidation of the molecular events occurring during tumorigenesis may provide new markers that are likely to be both specific for cancer and sensitive for early disease. The key molecules undergoing alterations during carcinogenesis are the cellular oncogenes and suppressor genes. Alterations in these genes can be detected in cells shed from malignant and premalignant lesions. Thus, mutant p53 genes have been found in urine from patients with bladder cancer, mutant ras genes in stools from patients with colorectal and pancreatic cancers, and both mutant p53 and ras genes in sputum from patients with lung cancer. These findings show that the genetic alterations in cancer can be detected in fluids or secretions that had contact with the malignant tissue. The preliminary studies, however, had small numbers of both patients and controls and used time-consuming, labor-intensive, and expensive assays. For routine applications, these assays must be simplified, automated, and tested for sensitivity, specificity, and predictive value.
Free and complexed prostate-specific antigen (PSA): in vitro stability, epitope map, and development of immunofluorometric assays for specific and sensitive detection of free PSA and PSA-alpha 1-antichymotrypsin complex
Authors: Pettersson K , Piironen T , Seppälä M , Liukkonen L , Christensson A , Matikainen M T , Suonpää M , Lövgren T , Lilja H 
Published: January 2020

Abstract
Generation of 15 monoclonal antibodies (MAbs) allowed construction of epitope maps and specific two-site immunofluorometric assays for free prostate-specific antigen (PSA) and PSA complexed with alpha 1-antichymotrypsin (ACT). Close correlation of PSA concentrations obtained with the use of different assays of free PSA suggested extensive similarity in immunodetection of free PSA in serum. Assays of the PSA-ACT complex overestimated the concentration of PSA-ACT in serum because of nonspecific adsorbance of ACT or cathepsin G-complexed ACT to the solid phase. This interference was substantially decreased in the presence of heparin. In studying the stability of purified PSA and PSA-ACT complexes formed in vitro, we found that the free PSA was stable during storage for 4 weeks at 35 degrees C, whereas PSA-ACT complexes largely dissociated in these conditions. The instability of PSA-ACT complexes was counteracted by storage at low temperatures, by adjusting the pH of the storage buffer between 6.8 and 7.4, and through addition of 100-1000-fold molar excess of native ACT. The ease of calibration and the accuracy of free PSA assays in comparison with assays of the PSA-ACT complex suggest that measurements of free to total PSA most accurately reflect the inverse of the proportion of PSA complexed to ACT in serum.
AquaLite bioluminescence assay of thyrotropin in serum evaluated
Authors: Sgoutas D S , Tuten T E , Verras A A , Love A , Barton E G 
Published: January 2020

Abstract
We studied a new commercially available thyrotropin (TSH) assay, the AquaLite Bioluminescence TSH-Immunoassay (SeaLite Inc.). This assay has a detection limit of 0.005 mIU/L and a functional sensitivity of 0.017 mIU/L and meets the requirements of a third-generation TSH assay. Using this assay, we measured serum TSH in 153 euthyroid individuals and in the following patients: 32 primary hypothyroids; 38 primary hyperthyroids; 35 with thyroid cancer receiving suppressive therapy with levothyroxine (L-T4); 33 receiving replacement L-T4 aimed at reaching and maintaining a euthyroid status; 23 with subclinical hyperthyroidism; and 52 hospitalized for nonthyroidal illnesses (NTI). The AquaLite TSH assay perfectly discriminated hypothyroid and untreated hyperthyroid patients from euthyroid subjects and clearly discriminated between overtly and mildly hyperthyroid patients. Intermethod comparisons showed that the AquaLite and the Nichols assays were more effective than the ACS-180 and the TOSOH assays in discriminating among hyperthyroid patients, including patients over-treated with L-T4.
Detection of point mutations in T lymphocytes
Authors: van Zeeland A A , Jansen J G , Mohn G R , Vrieling H , Tates A D , Lohman P H 
Published: January 2020

Abstract
We exposed experimental animals to a series of alkylating agents that induced mutations at the X-linked hprt gene of T lymphocytes. We then isolated the mutant cells and analyzed the molecular nature of the mutations by amplification of hprt cDNA sequences with the use of reverse transcriptase PCR followed by DNA sequence analysis, and then correlated the mutational spectra obtained to the spectra of DNA adducts caused by the alkylating agents used. The nature of the base-pair changes causing the mutations was characteristic for the reaction pattern of the genotoxic agent with DNA. However, we also found a clear influence of DNA repair processes; i.e., in those cells that were able to remove certain types of DNA damage, the class of mutations expected from that type of damage was reduced.
Prostatic acid phosphatase assay with self-indicating substrate 2,6-dichloro-4-acetylphenyl phosphate
Authors: Osawa S , Iida S , Yonemitsu H , Kuroiwa K , Katayama K , Nagasawa T 
Published: January 2020

Abstract
We characterized six self-indicating substrates, synthesized as the derivative compounds of acetylphenyl phosphate, for serum prostatic acid phosphatase (PAP) activity. One of the substrates, 2,6-dichloro-4-acetylphenyl phosphate (DCAPP), is superior to others in terms of stability, affinity, and low Km for PAP. The hydrolyzed product, 2,6-dichloro-4-acetylphenol (DCAP), has a maximum absorption at 334.2 nm, a pKa of 4.15, and a molar absorptivity at 340 nm of 21,490 L.mol-1.cm-1 in citrate-HCl buffer, pH 5.4. PAP activity was assessed by subtracting tartaric acid-inhibited acid phosphatase activity from total acid phosphatase activity. Our assay system involving DCAPP is a unique kinetic method that shows good reproducibility, wide analytical dynamic range, and high specificity for PAP. Moreover, it is easily adaptable to automated analyzers because the product, DCAP, can be monitored at 340 nm.
Ultrasensitive assay of prostate-specific antigen used for early detection of prostate cancer relapse and estimation of tumor-doubling time after radical prostatectomy
Authors: Yu H , Diamandis E P , Prestigiacomo A F , Stamey T A 
Published: January 2020

Abstract
We used an ultrasensitive prostate-specific antigen (PSA) assay with a detection limit of 0.02 microgram/L for long-term monitoring of PSA changes in 5 patients who were cured by radical prostatectomy and in 10 patients who had failed prostatectomies; 5 patients who underwent cystoprostatectomy were also evaluated with one sample after surgery. Relapse-free periods, determined on the basis of criteria designed specifically for the ultrasensitive assay or proposed for other currently available PSA assays, were calculated for the patients with failed prostatectomies. Tumor-doubling times were also calculated, postsurgery, according to a model that assumes exponential tumor growth over time. We found that prostate cancer relapse, on average, could be diagnosed 420 or 883 days earlier with the ultrasensitive assay than with assays having detection limits of 0.1 or 0.3 microgram/L, respectively. Tumor-doubling times, calculated after radical prostatectomy, ranged from 67 to 568 days among the 10 patients. We also present evidence that even more-sensitive PSA assays might be able to further reduce the relapse-free periods in approximately 50% of the prostate cancer patients who ultimately relapse.
Two alpha-chain hemoglobin variants, Hb Broussais and Hb Cemenelum, characterized by cation-exchange HPLC, isoelectric focusing, and peptide sequencing
Authors: Turpeinen U , Sipilä I , Anttila P , Karjalainen U , Kuronen B , Kalkkinen N , Ahola T , Stenman U H 
Published: January 2020

Abstract
We here report the characteristics of two rare alpha-chain hemoglobin (Hb) variants. The variants were found during quantification of HbA1c by cation-exchange HPLC with the Diamat glycohemoglobin analyzer. They were further characterized by isoelectric focusing and PolyCAT A cation-exchange chromatography. The structure of the abnormal Hbs was established by amino acid analysis after separation of the globin chains by reversed-phase chromatography, digestion with trypsin, separation of the peptides by reversed-phase chromatography, and amino acid sequencing. These studies showed that the two variants were Hb Broussais [alpha 90 (FG2)Lys--&gt;Asn] and Hb Cemenelum [alpha 92 (FG4)Arg--&gt;Trp].
Chromatographic evaluation of minor hemoglobins: clinical significance of hemoglobin A1d, comparison with hemoglobin A1c, and possible interferences
Authors: Bissé E , Huaman-Guillen P , Wieland H 
Published: January 2020

Abstract
Using an HPLC procedure, we evaluated &gt; 10 minor hemoglobins (Hbs) in healthy adults, individuals on long-term aspirin therapy, diabetic subjects, and uremic patients. Hb A1c and Hb A1d3 were the most abundant and important minor Hb components, respectively, accounting for 4.10% +/- 0.50% and 3.46% +/- 0.43% of total Hb in 361 healthy subjects. Acetylated Hb A was a potential interferent in the measurement of Hb A1c. The amounts of both Hb A1d3 and Hb A1carb were significantly increased in uremic patients, indicating that these Hb adducts may be carbamylated. There was a significant correlation (r = 0.69, P &lt; 0.0001) between the amounts of Hb A1d3 and plasma urea in uremic patients. Nonuremic subjects were clearly separated from uremic patients with regard to the Hb A1d3 content of their total Hb. Our data suggest that Hb A1d3 is useful for assessment of the uremic state and that the combination of Hb A1c and Hb A1d3 could be well-suited for simultaneous control of carbohydrate and urea metabolism.
Rapid gas-chromatographic assay of lactulose and mannitol for estimating intestinal permeability
Authors: Celli M , D'Eufemia P , Dommarco R , Finocchiaro R , Aprigliano D , Martino F , Cardi E , Giardini O 
Published: January 2020

Abstract
We developed a gas-chromatographic method to determine urinary mannitol and lactulose. The procedure for purification of urine by a resin was optimized for purification of analytes and high recovery; the aliquot of resin chosen (500 mg) was kept in contact with the urine for 1 min. The recoveries of mannitol and lactulose were &gt; 85% at concentrations that include both normal and pathological values. Sugars were converted to oximes before the silylation step to avoid multiple peaks for the anomeric forms. The calibration was linear over the range 0.1-1 microgram of sugar injected. Analytical recovery of the sugars ranged from 90% to 95.3% for mannitol and from 90.4% to 95.8% for lactulose. The mean within-day imprecision (CV) was 6.2% for mannitol and 4.7% for lactulose; the between-day CV was 6.7% for mannitol and 5.1% for lactulose. A lactulose/mannitol ratio of 0.035 completely differentiated 28 normal children and 28 children with active gluten-sensitive enteropathy, whose mean ratios were 0.022 (SD 0.007) and 0.084 (SD 0.054), respectively.
Diagnosis of human heritable diseases--laboratory approaches and outcomes
Authors: Dowton S B , Slaugh R A 
Published: January 2020

Abstract
Detection of mutant human genes is rapidly becoming an integral part of clinical practice. Human disease may arise by genetic deletion, insertion, fusion, point mutation, or amplification of unstable sequences. Such changes in structure may occur in germ cells or somatically. Rapid advances in understanding the complex nuclear and mitochondrial genomes necessitates deployment of a variety of methods to identify aberrant genes. These techniques include polymerase chain reaction, Southern transfer, and allele-specific hybridization studies, as well as methods to unmask mismatches between mutant and normal sequences. Development of protein truncation tests has added a vehicle for assessing larger DNA segments for mutations that cause premature translational termination. Linkage analysis remains an important tool where direct assay of disease-causing mutations is not possible. Considerations of confidentiality, informed consent, and insurability are important whenever genetic testing is used. These issues will assume increasing importance as presymptomatic testing for heritable predispositions emerges for common conditions.
For goodness' sake: expected therapeutic benefit as a basis for healthcare delivery
Authors: Denton T A , Diamond G A 
Published: January 2020

Abstract
The current debate on our healthcare system has focused primarily on the cost of care. Because of drastically rising costs and their burden on our economy, government and the private sector have developed many approaches to reduce these costs. Managed care, special contracting arrangements, and government fiat have all been used to stem the tide of rising costs--with variable success. We propose that the primary goal of healthcare is the provision of patient benefit, and we describe a model that calculates an expected benefit in terms of survival and quality of life. We have applied this model to a cohort of patients undergoing coronary angiography to determine the distributions of benefit. Furthermore, we describe a reimbursement strategy that relates the expected therapeutic benefit to the reimbursement received for that therapy--the greater the benefit, the greater the reimbursement. The future of our healthcare system lies in keeping the patient at the center of the debate on the delicate balance between optimal care and societal cost.