Trends in Blood Lead Levels Quantified by ICP-MS: A Reference Laboratory Retrospective Study.

BACKGROUND: Exposure to lead may cause severe adverse effects such as anemia, neurologic damage, developmental disorders, and reproductive disorders. Consequently, in 2021, the Centers for Disease Control and Prevention (CDC) reduced its blood lead reference value from 5 µg/dL to 3.5 µg/dL in pediatric patients, 1 to 5 years old. The objective of this study was to perform a retrospective analysis of patient blood lead concentrations reported by ARUP Laboratories to evaluate the frequency of blood lead concentrations greater than 3.5 µg/dL. METHODS: The analysis of blood lead concentration was performed in venous whole blood specimens using inductively coupled plasma mass spectrometry (ICP-MS). In addition, retrospective data analysis was performed to evaluate zinc protoporphyrin (ZPP) concentrations in adult patients with corresponding lead results, using the lead industrial exposure panel. The analysis for ZPP was performed using quantitative hematofluorometry. RESULTS: Retrospective data analysis identified a decline in blood lead concentrations from 2012 to 2021 for pediatric and adult patients. The calculated nonparametric 95% range for ZPP blood was 15 to 43 µg/dL and the ZPP heme ratio 26 to 74 µmol ZPP/mol heme. CONCLUSIONS: Lowering the blood lead reference value (BLRV) to 3.5 µg/dL presents an opportunity for healthcare providers and public health agencies to extend medical or environmental interventions for lead exposure in pediatric patients.

The Serological Sciences Network (SeroNet) for COVID-19: Depth and Breadth of Serology Assays and Plans for Assay Harmonization.

In October 2020, the National Cancer Institute (NCI) Serological Sciences Network (SeroNet) was established to study the immune response to COVID-19, and "to develop, validate, improve, and implement serological testing and associated technologies" (https://www.cancer.gov/research/key-initiatives/covid-19/coronavirus-research-initiatives/serological-sciences-network). SeroNet is comprised of 25 participating research institutions partnering with the Frederick National Laboratory for Cancer Research (FNLCR) and the SeroNet Coordinating Center. Since its inception, SeroNet has supported collaborative development and sharing of COVID-19 serological assay procedures and has set forth plans for assay harmonization. To facilitate collaboration and procedure sharing, a detailed survey was sent to collate comprehensive assay details and performance metrics on COVID-19 serological assays within SeroNet. In addition, FNLCR established a protocol to calibrate SeroNet serological assays to reference standards, such as the U.S. severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serology standard reference material and first WHO international standard (IS) for anti-SARS-CoV-2 immunoglobulin (20/136), to facilitate harmonization of assay reporting units and cross-comparison of study data. SeroNet institutions reported development of a total of 27 enzyme-linked immunosorbent assay (ELISA) methods, 13 multiplex assays, and 9 neutralization assays and use of 12 different commercial serological methods. FNLCR developed a standardized protocol for SeroNet institutions to calibrate these diverse serological assays to reference standards. In conclusion, SeroNet institutions have established a diverse array of COVID-19 serological assays to study the immune response to SARS-CoV-2 and vaccines. Calibration of SeroNet serological assays to harmonize results reporting will facilitate future pooled data analyses and study cross-comparisons. IMPORTANCE SeroNet institutions have developed or implemented 61 diverse COVID-19 serological assays and are collaboratively working to harmonize these assays using reference materials to establish standardized reporting units. This will facilitate clinical interpretation of serology results and cross-comparison of research data.

The Serological Sciences Network (SeroNet) for COVID-19: Depth and Breadth of Serology Assays and Plans for Assay Harmonization.

Background: In October 2020, the National Cancer Institute (NCI) Serological Sciences Network (SeroNet) was established to study the immune response to COVID-19, and "to develop, validate, improve, and implement serological testing and associated technologies." SeroNet is comprised of 25 participating research institutions partnering with the Frederick National Laboratory for Cancer Research (FNLCR) and the SeroNet Coordinating Center. Since its inception, SeroNet has supported collaborative development and sharing of COVID-19 serological assay procedures and has set forth plans for assay harmonization. Methods: To facilitate collaboration and procedure sharing, a detailed survey was sent to collate comprehensive assay details and performance metrics on COVID-19 serological assays within SeroNet. In addition, FNLCR established a protocol to calibrate SeroNet serological assays to reference standards, such as the U.S. SARS-CoV-2 serology standard reference material and First WHO International Standard (IS) for anti-SARS-CoV-2 immunoglobulin (20/136), to facilitate harmonization of assay reporting units and cross-comparison of study data. Results: SeroNet institutions reported development of a total of 27 ELISA methods, 13 multiplex assays, 9 neutralization assays, and use of 12 different commercial serological methods. FNLCR developed a standardized protocol for SeroNet institutions to calibrate these diverse serological assays to reference standards. Conclusions: SeroNet institutions have established a diverse array of COVID-19 serological assays to study the immune response to SARS-CoV-2 virus and vaccines. Calibration of SeroNet serological assays to harmonize results reporting will facilitate future pooled data analyses and study cross-comparisons.

Recovery, recycling and re-irradiation of enriched 104Ru metal targets for cost effective production of 105Rh.

Rhodium-105 (0.567 MeV ß-, 319 keV γ, 35.4 h half-life) was produced by neutron irradiation of enriched 104Ru (>99%) over multiple decades. A method is reported to recover the previously irradiated 104Ru (trapped in HCl as RuO42-) as the metal. The 104Ru was recovered in >93% yield and >98% enrichment. Neutron re-irradiation of the recycled 104Ru produced 105Rh, which was successfully radiolabeled with tetrathioethers in high yield. This recovery and recycling method for enriched 104Ru makes 105Rh production and utilization economical.

Performance Characteristics of BinaxNOW COVID-19 Antigen Card for Screening Asymptomatic Individuals in a University Setting.

We compared the performance of the Abbott BinaxNOW COVID-19 antigen card to that of a standard reverse transcription-PCR (RT-PCR) assay (Thermo Fisher TaqPath COVID-19 Combo kit) for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2,645 asymptomatic students presenting for screening at the University of Utah. SARS-CoV-2 RNA was detected in 1.7% of the study participants by RT-PCR. BinaxNOW identified 24 infections but missed 21 infections that were detected by RT-PCR. The analytical sensitivity (positive agreement) and analytical specificity (negative agreement) for the BinaxNOW were 53.3% and 100%, respectively, compared to the RT-PCR assay. The median cycle threshold (CT ) value in the specimens that had concordant positive BinaxNOW antigen results was significantly lower than that of specimens that were discordant (CT of 17.6 versus 29.6; P < 0.001). In individuals with presumably high viral loads (CT of <23.0), a 95.8% positive agreement was observed between the RT-PCR assay and BinaxNOW. Due to the possibility of false-negative results, caution must be taken when utilizing rapid antigen testing for screening asymptomatic individuals.

Patterns of Neonatal Co-Exposure to Gabapentin and Commonly Abused Drugs Observed in Umbilical Cord Tissue.

Gabapentin was thought to have low abuse potential, but it is increasingly being abused by people with substance use disorder in an attempt to potentiate the euphoric effects from opioids and other CNS depressants. Additionally, infants co-exposed to gabapentin and opioids during pregnancy tend to exhibit prolonged and more severe neonatal abstinence syndrome. In this study, we describe positivity rates among commonly abused drugs and rates of co-medication with gabapentin in a large dataset of umbilical cord tissue specimens (n = 25,422) submitted for routine newborn drug testing at a national clinical reference laboratory (ARUP Laboratories, Salt Lake City, UT, USA). Detection of prenatal drug exposure in umbilical cord tissue specimens was accomplished using a semi-quantitative liquid chromatography-tandem mass spectrometry assay designed to detect 47 specific drugs and drug metabolites including opioids, stimulants, sedative-hypnotics and hallucinogens. A positive result for at least one of the measured drugs or drug metabolites was reported in 7,054 (28%) of the umbilical cord tissues analyzed. Gabapentin had a positivity rate of ~2% with 562 positive results. Of the 562 gabapentin-positive samples, 395 (70%) also had a positive result for at least one other drug or drug metabolite, with the highest co-positivity rate observed for norbuprenorphine (32%, n = 182) followed by amphetamine (15%, n = 84), buprenorphine (13%, n = 74), methamphetamine (12%, n = 68), morphine (11%, n = 64), fentanyl (10%, n = 54) and naloxone (10%, n = 54). Notably, the concentration of gabapentin in gabapentin-positive umbilical cord specimens was higher in buprenorphine-containing specimens as compared to specimens containing other opioids, stimulants or benzodiazepines. Identification of neonatal co-exposure to gabapentin and opioids, particularly buprenorphine, may guide clinicians in rapid initiation of monitoring and intervention for neonatal abstinence syndrome.

Evaluation of 72Se/72As generator and production of 72Se for supplying 72As as a potential PET imaging radionuclide.

Positron-emitting 72As is the PET imaging counterpart for beta-emitting 77As. Its parent, no carrier added (n.c.a.) 72Se, was produced for a 72Se/72As generator by irradiating an enriched 7°Ge metal-graphite target via the 70Ge(α, 2 n)72Se reaction. Target dissolution used a fast, environmentally friendly method with 93% radioactivity recovery. Chromatographic parameters of the 72Se/72As generator were evaluated, the eluted n.c.a. 72As was characterized with a phantom imaging study, and the previously reported trithiol and aryl-dithiol ligand systems were radiolabeled with the separated n.c.a. 72As in high yield.

A trithiol bifunctional chelate for 72,77As: A matched pair theranostic complex with high in vivo stability.

INTRODUCTION: Trithiol chelates are suitable for labeling radioarsenic (72As: 2.49 MeV ß+, 26 h; 77As: 0.683 MeV ß-, 38.8 h) to form potential theranostic radiopharmaceuticals for PET imaging and therapy. To investigate the in vivo stability of trithiol chelates complexed with no carrier added (nca) radioarsenic, a bifunctional trithiol chelate was developed, and conjugated to bombesin(7-14)NH2 as a model peptide. METHODS: A trithiol-BBN(7-14)NH2 bioconjugate and its arsenic complex were synthesized and characterized. The trithiol-BBN(7-14)NH2 conjugate was radiolabeled with 77As, its in vitro stability assessed, and biodistribution studies were performed in CF-1 normal mice of free [77As]arsenate and 77As-trithiol- BBN(7-14)NH2. RESULTS: The trithiol-BBN(7-14)NH2 conjugate, its precursors and its As-trithiol-BBN(7-14)NH2 complex were fully characterized. Radiolabeling studies with nca 77As resulted in over 90% radiochemical yield of 77As-trithiol-BBN, which was stable for over 48 h. Biodistribution studies were performed with both free [77As]arsenate and Sep-Pak® purified 77As-trithiol-BBN(7-14)NH2. Compared to the fast renal clearance of free [77As]arsenate, 77As-trithiol-BBN(7-14)NH2 demonstrated increased retention with clearance mainly through the hepatobiliary system, consistent with the lipophilicity of the 77As-trithiol-BBN(714)NH2 complex. CONCLUSION: The combined in vitro stability of 77As-trithiol-BBN(7-14)NH2 and the biodistribution results demonstrate its high in vivo stability, making the trithiol a promising platform for developing radioarsenic-based theranostic radiopharmaceuticals.