bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kinetic Analyses of Parathyroid Hormone Clearance as Measured by Three Rapid Immunoassays during Parathyroidectomy
Authors: Bieglmayer Christian , Prager Gerhard , Niederle Bruno 
Published: January 2020

Abstract
Background: Rapid intraoperative parathyroid hormone (PTH) measurements are an important prerequisite for minimally invasive parathyroidectomy, serving as a feasible marker for “cure” because of the short half-life of PTH. Because automated analysis may facilitate monitoring, two automated PTH assays were compared with an established manual method.
Methods: We collected 109 plasma samples during minimally invasive surgery on 20 patients with primary hyperparathyroidism and single-gland disease. PTH was analyzed manually with a test from Nichols and by two automated assays from Diagnostic Product Corporation (DPC) and Roche, respectively. PTH half-life and residual concentrations were calculated by two kinetic models.
Results: Despite good overall correlations between methods [DPC = 1.07(Nichols) − 12 ng/L; r = 0.95, Sy|x = 26 ng/L and Roche = 1.16(Nichols) − 2.82 ng/L; r = 0.98; Sy|x = 16 ng/L], marked interindividual differences were observed. The iterative kinetic model failed with a nonuniform PTH decrease, but the interpolative model produced valid results. The mean (SD) half-life of 3.7 ± 1.4 min with DPC differed significantly (P &lt;0.05) from the 4.3 ± 1.6 min with Roche (Nichols, 4.0 ± 1.6 min). DPC produced significantly lower mean residual PTH (15 ng/L) vs Roche (27 ng/L); Nichols results were between them (20 ng/L). However, these differences were clinically irrelevant.
Conclusions: Automated methods are as suitable as the manual test. The preoperative baseline PTH is necessary but is insufficient for kinetic calculations.
Automated Transport and Sorting System in a Large Reference Laboratory: Part 1. Evaluation of Needs and Alternatives and Development of a Plan
Authors: Hawker Charles D , Garr Susan B , Hamilton Leslie T , Penrose John R , Ashwood Edward R , Weiss Ronald L 
Published: January 2020

Abstract
Background: Our laboratory, a large, commercial, esoteric reference laboratory, sought some form of total laboratory automation to keep pace with rapid growth of specimen volumes as well as to meet competitive demands for cost reduction and improved turnaround time.
Methods: We conducted a systematic evaluation of our needs, which led to the development of a plan to implement an automated transport and sorting system. We systematically analyzed and studied our specimen containers, test submission requirements and temperatures, and the workflow and movement of people, specimens, and information throughout the laboratory. We performed an intricate timing study that identified bottlenecks in our manual handling processes. We also evaluated various automation options.
Results: The automation alternative viewed to best meet our needs was a transport and sorting system from MDS AutoLab. Our comprehensive plan also included a new standardized transport tube; a centralized automated core laboratory for higher volume tests; a new “automation-friendly” software system for order entry, tracking, and process control; a complete reengineering of our order-entry, handling, and tracking processes; and remodeling of our laboratory facility and specimen processing area.
Conclusions: The scope of this project and its potential impact on overall laboratory operations and performance justified the extensive time we invested (nearly 4 years) in a systematic approach to the evaluation, design, and planning of this project.
Design and Use of a Peptide Nucleic Acid for Detection of the Heteroplasmic Low-Frequency Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-like Episodes (MELAS) Mutation in Human Mitochondrial DNA
Authors: Hancock Diane K , Schwarz Frederick P , Song Fenhong , Wong Lee-Jun C , Levin Barbara C 
Published: January 2020

Abstract
Background: Most pathogenic human mitochondrial DNA (mtDNA) mutations are heteroplasmic (i.e., mutant and wild-type mtDNA coexist in the same individual) and are difficult to detect when their concentration is a small proportion of that of wild-type mtDNA molecules. We describe a simple methodology to detect low proportions of the single base pair heteroplasmic mutation, A3243G, that has been associated with the disease mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) in total DNA extracted from blood.
Methods: Three peptide nucleic acids (PNAs) were designed to bind to the wild-type mtDNA in the region of nucleotide position 3243, thus blocking PCR amplification of the wild-type mtDNA while permitting the mutant DNA to become the dominant product and readily discernable. DNA was obtained from both apparently healthy and MELAS individuals. Optimum PCR temperatures were based on the measured ultraviolet thermal stability of the DNA/PNA duplexes. The presence or absence of the mutation was determined by sequencing.
Results: In the absence of PNAs, the heteroplasmic mutation was either difficult to detect or undetectable by PCR and sequencing. Only PNA 3 successfully inhibited amplification of the wild-type mtDNA while allowing the mutant mtDNA to amplify. In the presence of PNA 3, we were able to detect the heteroplasmic mutation when its concentration was as low as 0.1% of the concentration of the wild-type sequence.
Conclusion: This methodology permits easy detection of low concentrations of the MELAS A3243G mutation in blood by standard PCR and sequencing methods.
Direct Assay for Cobalamin Bound to Transcobalamin (Holo-Transcobalamin) in Serum
Authors: Ulleland Marius , Eilertsen Ingar , Quadros Edward V , Rothenberg Sheldon P , Fedosov Sergey N , Sundrehagen Erling , Örning Lars 
Published: January 2020

Abstract
Background: Only cobalamin carried by transcobalamin (holo-transcobalamin) is available for cellular uptake and hence is physiologically relevant. However, no reliable or accurate methods for quantifying holo-transcobalamin are available. We report a novel holo-transcobalamin assay based on solid-phase capture of transcobalamin.
Methods: A monoclonal antibody specific for human transcobalamin with an affinity constant &gt;1010 L/mol was immobilized on magnetic microspheres to capture and concentrate transcobalamin. The cobalamin bound to transcobalamin was then released and assayed by a competitive binding radioassay. The quantification of holo-transcobalamin was accomplished using calibrators composed of recombinant, human holo-transcobalamin.
Results: The assay was specific for holo-transcobalamin and had a detection limit of 5 pmol/L. Within-run and total imprecision (CV) was 5% and 8–9%, respectively. The working range (CV &lt;20%) was 5–370 pmol/L. Dilutions of serum were linear in the assay range. The recovery of recombinant, human holo-transcobalamin added to serum was 93–108%. A 95% reference interval of 24–157 pmol/L was established for holo-transcobalamin in 105 healthy volunteers 20–80 years of age. For 72 of these sera, holo-haptocorrin and total cobalamin were also determined. Whereas holo-haptocorrin correlated well (r2 = 0.87) with total cobalamin, holo-transcobalamin correlated poorly (r2 = 0.23) with total cobalamin or holo-haptocorrin.
Conclusions: The solid-phase capture assay provides a simple, reliable method for quantitative determination of holo-transcobalamin in serum.
Bioluminescent Method for Detecting Telomerase Activity
Authors: Xu Shun-Qing , He Min , Yu Hong-Ping , Wang Xiao-Yang , Tan Xiang-Lin , Lu Bin , Sun Xi , Zhou Yi-Kai , Yao Qun-Feng , Xu Yong-Jun , Zhang Zhi-Ren 
Published: January 2020

Abstract
Background: Telomerase is a promising biomarker in cancer diagnosis and therapy. The elongation of telomeric repeats catalyzed by telomerase is accompanied by release of six PPi for each TTAGGG repeat (1 pmol PPi/310 pg telomeric repeats). We developed a novel method to measure telomerase activity by use of an enzymatic luminometric PPi assay (ELIPA).
Methods: Extracts of cell lines and tissues were incubated with primer at 30 °C for 30 min. Released PPi was converted to ATP by sulfurylase, and ATP was detected by a luciferase bioluminescence system. The ELIPA results were compared with results obtained with the conventional telomeric repeat amplification (TRAP)-ELISA in 42 lung carcinoma tissues and 27 control tissues without malignancy.
Results: The lower detection limits of ELIPA and TRAP-ELISA were 5 and 10 cells, respectively. The within-run imprecision (CV) of ELIPA was ≤12%. When compared with TRAP-ELISA, the correlation coefficient (r) was 0.79. When we used the cutoff value from ROC analysis to distinguish malignant and nonmalignant tissues, the sensitivity and specificity of ELIPA were 83% and 96%, respectively, whereas the sensitivity and specificity of TRAP-ELISA were 71% and 96%, respectively.
Conclusion: ELIPA is a simple and sensitive homogeneous method to quantify telomerase activity.
Cancer Biomarkers: Easier Said Than Done
Authors: Pritzker Kenneth PH 
Published: January 2020

Abstract
Background: Biological and technical advances have led to greatly increased research and development of cancer biomarkers. This overview lists some of the challenges and barriers to developing novel effective cancer biomarkers and enablers to facilitate cancer biomarker development.
Methods: Current scientific literature regarding development of biomarkers for cancer and other diseases was reviewed.
Results: Challenges to developing cancer biomarkers include better understanding of biological heterogeneity, including host/tumor heterogeneity; analytical factors, such as interferences and analytical sensitivity; clinical pathologic factors, such as current histopathologic standards; and health service and market factors. More standardized biomarker definitions, standardization of cancer biology terminology, and high-quality reference materials (specimen and clinical data repositories) were identified as factors required to support advances in cancer biomarkers.
Conclusions: With the above enablers, novel cancer biomarkers may be useful, both for assessing early and established neoplasia more precisely and for contributing data toward development of novel practical concepts regarding cancer biology.
Measurement of the Noncomplexed Free Fraction of Tissue Inhibitor of Metalloproteinases 1 in Plasma by Immunoassay
Authors: Holten-Andersen Mads N , Christensen Ib Jarle , Nielsen Hans Jørgen , Lilja Hans , Murphy Gillian , Jensen Vibeke , Brünner Nils , Piironen Timo 
Published: January 2020

Abstract
Background: We previously found differences in total concentrations of tissue inhibitor of metalloproteinases 1 (TIMP-1) in plasma from donors and cancer patients. Because TIMP-1 can exist in more than one molecular form, a new immunoassay to specifically detect free TIMP-1 was developed and concentrations were determined in plasma from healthy donors and colorectal cancer (CRC) patients.
Methods: We established and validated an immunoassay for the specific measurement of free TIMP-1 that uses a polyclonal anti-TIMP-1 antibody for capture and a monoclonal anti-TIMP-1 antibody that binds only free TIMP-1 for detection of antigen. Plasma samples from healthy donors and CRC patients were assayed for free TIMP-1. Total TIMP-1 was measured by our previously published assay.
Results: The mean (SD) concentrations of free TIMP-1 were similar in citrate [55.5 (11.5) μg/L] and EDTA plasma [58.9 (13.3) μg/L] from 76 donors (r2 = 0.82). In 154 donors, the ratio of free TIMP-1 [mean (SD), 64.5 (18.0) μg/L] to total TIMP-1 [83.8 (19.8) μg/L] in EDTA plasma was 0.77. Plasma concentrations of free and total TIMP-1 correlated significantly to age (free, r2 = 0.19; total, r2 = 0.27; P &lt;0.0001), increasing 50% over an age span of 45 years. Free and total TIMP-1 were significantly increased in CRC patients (P &lt;0.0001), whereas the ratio of free to total TIMP-1 (mean, 0.58) was significantly lower than in donors.
Conclusions: Most of the TIMP-1 in donor plasma is present in its free form, and free TIMP-1 increases with age. Free and total TIMP-1 are increased in CRC patient plasma, but the ratio of free to total TIMP-1 is significantly lower in these patients than in donors.
Temperature-controlled Primer Limit for Multiplexing of Rapid, Quantitative Reverse Transcription-PCR Assays: Application to Intraoperative Cancer Diagnostics
Authors: Raja Siva , El-Hefnawy Talal , Kelly Lori A , Chestney Melissa L , Luketich James D , Godfrey Tony E 
Published: January 2020

Abstract
Background: Rapid-cycling, real-time PCR instruments bring the opportunity for improved intraoperative detection of metastasis to sentinel lymph nodes. Rapid, standardized, and internally controlled assays need to be developed that are sensitive and accurate.
Methods: We describe rapid, multiplexed, internally controlled, quantitative reverse transcription-PCR (QRT-PCR) assays for tyrosinase and carcinoembryonic antigen mRNAs on the SmartCycler (Cepheid). We used a temperature-controlled primer-limiting approach to eliminate amplification of the endogenous control gene as soon as its signal had reached threshold. Positive-control oligonucleotide mimics were incorporated into all reactions to differentiate failed reactions from true negative samples.
Results: The optimized assays for rapid QRT-PCR yielded results with threshold cycle values that were only 1–2 cycles higher than slower, more conventional protocols. In rapid PCR, the temperature-controlled multiplex assay was quantitative over a dynamic range of at least 15 cycles, compared with only 6 cycles for conventional multiplexing methods. All histologically positive lymph nodes examined were also QRT-PCR positive for the appropriate marker, and the exogenous, internal positive-control mimics produced signals in all negative samples.
Conclusion: Internally controlled, rapid QRT-PCR assays can be performed in an intraoperative time frame and with sufficient sensitivity to detect histologically identified metastases to lymph nodes.
Genetic Covariation between Serum γ-Glutamyltransferase Activity and Cardiovascular Risk Factors
Authors: Whitfield John B , Zhu Gu , Nestler John E , Heath Andrew C , Martin Nicholas G 
Published: January 2020

Abstract
Background: Several studies have shown that variation in serum γ-glutamyltransferase (GGT) in the population is associated with risk of death or development of cardiovascular disease, type 2 diabetes, stroke, or hypertension. This association is only partly explained by associations between GGT and recognized risk factors. Our aim was to estimate the relative importance of genetic and environmental sources of variation in GGT as well as genetic and environmental sources of covariation between GGT and other liver enzymes and markers of cardiovascular risk in adult twin pairs.
Methods: We recruited 1134 men and 2241 women through the Australian Twin Registry. Data were collected through mailed questionnaires, telephone interviews, and by analysis of blood samples. Sources of variation in GGT, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) and of covariation between GGT and cardiovascular risk factors were assessed by maximum-likelihood model-fitting.
Results: Serum GGT, ALT, and AST were affected by additive genetic and nonshared environmental factors, with heritabilities estimated at 0.52, 0.48, and 0.32, respectively. One-half of the genetic variance in GGT was shared with ALT, AST, or both. There were highly significant correlations between GGT and body mass index; serum lipids, lipoproteins, glucose, and insulin; and blood pressure. These correlations were more attributable to genes that affect both GGT and known cardiovascular risk factors than to environmental factors.
Conclusions: Variation in serum enzymes that reflect liver function showed significant genetic effects, and there was evidence that both genetic and environmental factors that affect these enzymes can also affect cardiovascular risk.
Comparison of Two Provocative Tests for Calcitonin in Medullary Thyroid Carcinoma: Omeprazole vs Pentagastrin
Authors: Vitale Giovanni , Ciccarelli Antonio , Caraglia Michele , Galderisi Maurizio , Rossi Riccardo , Del Prete Salvatore , Abbruzzese Alberto , Lupoli Giovanni 
Published: January 2020

Abstract
Background: Provocative tests for calcitonin (CT) are fundamental in the diagnosis and follow-up of C-cell disease and in the detection of hereditary medullary thyroid carcinoma (MTC) carriers with unknown RET mutations. A recent report has proposed omeprazole, which can increase endogenous gastrin (GT), as a new provocative test for MTC.
Methods: We compared the omeprazole test (20 mg twice a day for 4 days) to the pentagastrin test (0.5 μg/kg of body weight) for the diagnosis and management of MTC. Twenty healthy individuals and 20 MTC patients with mildly or moderately increased basal CT serum concentrations underwent the pentagastrin and omeprazole tests.
Results: In MTC patients, the pentagastrin test produced a significantly higher increase in serum CT than did omeprazole. After the pentagastrin injection, several patients reported unpleasant side effects, including substantial tightness in 38 of 40 participants. No adverse effects were observed during the omeprazole test. A significant direct correlation was recorded between CT% (ratio of CT peak to basal value × 100) and GT% (ratio of GT peak to basal value × 100) during the omeprazole test in MTC patients (r = 0.73; P &lt;0.001).
Conclusions: In spite of several adverse effects, pentagastrin remains the best provocative test for the diagnosis of MTC. Omeprazole may be useful when pentagastrin is contraindicated or refused because of the unpleasant side effects, but further validation is needed.
The carnivorous digestive system and bamboo diet of giant pandas may shape their low gut bacterial diversity
Authors: Guo Wei , Chen Yinfeng , Wang Chengdong , Ning Ruihong , Zeng Bo , Tang Jingsi , Li Caiwu , Zhang Mingwang , Li Yan , Ni Qingyong , Ni Xueqin , Zhang Hemin , li Desheng , Zhao Jiangchao , Li Ying 
Published: January 2020

Abstract

Giant pandas have an exclusive diet of bamboo; however, their gut microbiotas are more similar to carnivores than herbivores in terms of bacterial composition and their functional potential. This is inconsistent with observations that typical herbivores possess highly diverse gut microbiotas. It is unclear why the gut bacterial diversity of giant pandas is so low. Herein, the dynamic variations in the gut microbiota of eight giant panda cubs were measured using 16S rRNA gene paired-end sequencing during a dietary switch. Similar data from red panda (an herbivorous carnivore) and carnivorous species were compared with that of giant pandas. In addition, mice were fed a high-bamboo diet (80% bamboo and 20% rat feed) to determine whether a bamboo diet could lower the gut bacterial diversity in a non-carnivorous digestive tract. The diversity of giant panda gut microbiotas decreased significantly after switching from milk and complementary food to bamboo diet. Carnivorous species living on a plant-based diet, including giant and red pandas, possess a lower microbial diversity than other carnivore species. Mouse gut microbiota diversity significantly increased after adding high-fibre bamboo to their diet. Findings suggest that a very restricted diet (bamboo) within a carnivorous digestive system might be critical for shaping a low gut bacterial diversity in giant pandas.
Glucagon-like peptide-1 receptor agonists and the risk of cardiovascular events in diabetes patients surviving an acute myocardial infarction
Authors: Trevisan Marco , Fu Edouard L , Szummer Karolina , Norhammar Anna , Lundman Pia , Wanner Christoph , Sjölander Arvid , Jernberg Tomas , Carrero Juan Jesus 
Published: January 2020

Abstract

Aims
Trial evidence indicates that glucagon-like peptide-1 receptor agonists (GLP-1 RAs) may reduce the risk of cardiovascular (CV) events in patients with diabetes and myocardial infarction (MI). We aimed to expand this observation to routine care settings.

Methods and results
Prospective observational study including all patients with diabetes surviving an MI and registered in the nationwide SWEDEHEART registry during 2010–17. Multivariable Cox regression analyses were used to estimate the association between GLP-1 RAs use and the study outcome, which was a composite of stroke, heart failure, Re-infarction, or CV death. Covariates included demographics, comorbidities, presentation at admission, and use of secondary CV prevention therapies. In total, 17 868 patients with diabetes were discharged alive after a first event of MI. Their median age was 71 years, 36% were women and their median estimated glomerular filtration rate was 75 mL/min/1.73m2. Of those, 365 (2%) were using GLP-1 RAs. During median 3 years of follow-up, 7005 patients experienced the primary composite outcome. Compared with standard of diabetes care, use of GLP-1 RAs was associated with a lower event risk [adjusted hazard ratio (HR) 0.72; 95% confidence interval (CI): 0.56–0.92], mainly attributed to a lower rate of re-infarction and stroke. Results were similar after propensity score matching or when compared with users of sulfonylurea. There was no suggestion of heterogeneity across subgroups of age, sex, chronic kidney disease, and STEMI.

Conclusion
GLP-1 RAs use, compared with standard of diabetes care, was associated with lower risk for major CV events in healthcare-managed survivors of an MI.
Technical aspects of uniportal video-assisted thoracoscopic double sleeve bronchovascular resections
Authors: Gonzalez-Rivas Diego , Garcia Alejandro , Chen Chang , Yang Yang , Jiang Lei , Sekhniaidze Dmitrii , Jiang Gening , Zhu Yuming 
Published: January 2020

Summary
Double sleeve, bronchial and vascular reconstructions are challenging procedures indicated for centrally located tumours to avoid pneumonectomy. Traditionally, these resections have been performed by thoracotomy, but thanks to advances in imaging systems, better surgical instruments and the gained experience in video-assisted thoracic surgery (VATS), the scenario now is different. During the last decade, we have seen a rapid evolution of the uniportal VATS technique from simple lobectomies to advanced double sleeve bronchovascular procedures and carinal resections. The advantages of VATS over open surgery for major lung resections in terms of postoperative pain and morbidity, length of hospital stay and quality of life have prompted experienced surgeons to adopt uniportal VATS for cases requiring a sleeve resection. However, when a double bronchial and vascular sleeve resection is required, the adoption rate of minimally invasive surgery is still very low even for very experienced VATS surgeons. The difficulty of tumour mobilization, complexity of the suturing technique and the concern about possible uncontrolled massive bleeding during VATS are the main reasons for this low rate of adoption. In this article, we describe the technical aspects and tricks of this procedure when it is done by the uniportal VATS approach.