The role of blood testing in prevention, diagnosis, and management of chronic diseases: A review.

Blood tests are vital to prevention, diagnosis, and management of chronic diseases. Despite this, it can be challenging to construct a comprehensive view of the clinical importance of blood testing because relevant literature is typically fragmented across different disease areas and patient populations. This lack of collated evidence can also make it difficult for primary care providers to adhere to best practices for blood testing across different diseases and guidelines. Thus, this review article synthesizes the recommendations for, and importance of, blood testing across several common chronic conditions encountered in primary care and internal medicine, including cardiovascular diseases, diabetes mellitus, chronic kidney disease, vitamin D deficiency, iron deficiency, and rheumatoid arthritis. Future research is needed to continue improving chronic disease management through clearer dissemination and awareness of clinical guidelines among providers, and better access to blood testing for patients (e.g., via pre-visit laboratory testing).

A medical chart audit to assess endocrinologist perceptions of the burden of endogenous Cushing's syndrome.

PURPOSE: This study was undertaken to assess the unmet needs within the endogenous Cushing's syndrome (CS) care paradigm from the endocrinologist's perspective, including data abstracted from patient charts. The study evaluated endocrinologists' perceptions on burden of illness and treatment rationale along with the long-term clinical burden of CS, tolerability of CS treatments, and healthcare resource utilization for CS. METHODS: Retrospective medical chart data from treated patients with a confirmed diagnosis of CS was abstracted using a cross-sectional survey to collect data from qualified endocrinologists. The survey included a case report form to capture patient medical chart data and a web-enabled questionnaire to capture practitioner-level data pertaining to endocrinologists' perceptions of disease burden, CS treatments, and treatment attributes. RESULTS: Sixty-nine endocrinologists abstracted data from 273 unique medical charts of patients with CS. Mean patient age was 46.5 ± 13.4 years, with a 60:40 (female:male) gender split. The mean duration of endogenous CS amongst patients was 4.1 years. Chart data indicated that patients experienced a high burden of comorbidities and symptoms, including fatigue, weight gain, and muscle weakness despite multi-modal treatment. When evaluating treatments for CS, endocrinologists rated improvement in health-related quality of life (HRQoL) as the most important treatment attribute (mean score = 7.8; on a scale of 1 = Not at all important to 9 = Extremely important). Surgical intervention was the modality endocrinologists were most satisfied with, but they agreed that there was a significant unmet treatment need for patients with CS. CONCLUSION: Endocrinologists recognized that patients with CS suffered from a debilitating condition with a high symptomatic and HRQoL burden and reported that improvement in HRQoL was the key treatment attribute influencing their treatment choices. This study highlights unmet needs for patients with CS. Patients with CS have a high rate of morbidity and comorbidity, even after treatment.

Systematic Literature Review of the Association of Fever and Elevated Temperature with Outcomes in Critically Ill Adult Patients.

Although most commonly associated with infection, elevated temperature and fever also occur in a variety of critically ill populations. Prior studies have suggested that fever and elevated temperature may be detrimental to critically ill patients and can lead to poor outcomes, but the evidence surrounding the association of fever with outcomes is rapidly evolving. To broadly assess potential associations of elevated temperature and fever with outcomes in critically ill adult patients, we performed a systematic literature review focusing on traumatic brain injury, stroke (ischemic and hemorrhagic), cardiac arrest, sepsis, and general intensive care unit (ICU) patients. Searches were conducted in Embase® and PubMed® from 2016 to 2021, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, including dual-screening of abstracts, full texts, and extracted data. In total, 60 studies assessing traumatic brain injury and stroke (24), cardiac arrest (8), sepsis (22), and general ICU (6) patients were included. Mortality, functional, or neurological status and length of stay were the most frequently reported outcomes. Elevated temperature and fever were associated with poor clinical outcomes in patients with traumatic brain injury, stroke, and cardiac arrest but not in patients with sepsis. Although a causal relationship between elevated temperature and poor outcomes cannot be definitively established, the association observed in this systematic literature review supports the concept that management of elevated temperature may factor in avoidance of detrimental outcomes in multiple critically ill populations. The analysis also highlights gaps in our understanding of fever and elevated temperature in critically ill adult patients.

Holistic burden of illness in patients with endogenous Cushing's syndrome: A systematic literature review.

OBJECTIVE: The objective of this systematic literature review (SLR) was to summarize the latest studies evaluating the burden of illness in endogenous Cushing's syndrome (CS), including the impact of CS on overall and domain-specific health-related quality of life (HRQoL) and the economic burden of CS to provide a holistic understanding of disease and treatment burden. METHODS: An SLR was conducted in PubMed, MEDLINE and Embase using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist to identify peer-reviewed manuscripts and conference abstracts published in English from 2015 to December 4, 2020. RESULTS: Forty-five publications were eligible for inclusion; data were extracted from 37 primary studies while 8 SLRs were included for reference only. Thirty-one studies reported HRQoL using validated patient reported outcome (PRO) measures in pre- or post-surgery, radiotherapy and pharmacotherapy patients. Overall, this SLR found that patients with CS have worse outcomes relative to healthy populations across specific dimensions, such as depression, despite an improvement in HRQoL post-treatment. These findings reveal that CS symptoms are not fully resolved by the existing care paradigm. Few studies report on the economic burden of CS and currently available data indicate a high direct healthcare system cost burden. CONCLUSIONS: Patients with CS experience a significant, complex and multifactorial HRQoL burden. Symptom-specific burden studies are sparse in the literature and the understanding of long-term CS symptomatic burden and economic burden is limited. This review intends to provide an updated reference for clinicians, payers and other stakeholders on the burden of CS as reported in published literature and to encourage further research in this area.

A Systematic Literature Review to Assess Fever Management and the Quality of Targeted Temperature Management in Critically Ill Patients.

Targeted temperature management (TTM) has been proposed to reduce mortality and improve neurological outcomes in postcardiac arrest and other critically ill patients. TTM implementation may vary considerably among hospitals, and "high-quality TTM" definitions are inconsistent. This systematic literature review in relevant critical care conditions evaluated the approaches to and definitions of TTM quality with respect to fever prevention and the maintenance of precise temperature control. Current evidence on the quality of fever management associated with TTM in cardiac arrest, traumatic brain injury, stroke, sepsis, and critical care more generally was examined. Searches were conducted in Embase and PubMed (2016 to 2021) following PRISMA guidelines. In total, 37 studies were identified and included, with 35 focusing on postarrest care. Frequently-reported TTM quality outcomes included the number of patients with rebound hyperthermia, deviation from target temperature, post-TTM body temperatures, and number of patients achieving target temperature. Surface and intravascular cooling were used in 13 studies, while one study used surface and extracorporeal cooling and one study used surface cooling and antipyretics. Surface and intravascular methods had comparable rates of achieving target temperature and maintaining temperature. A single study showed that patients with surface cooling had a lower incidence of rebound hyperthermia. This systematic literature review largely identified cardiac arrest literature demonstrating fever prevention with multiple TTM approaches. There was substantial heterogeneity in the definitions and delivery of quality TTM. Further research is required to define quality TTM across multiple elements, including achieving target temperature, maintaining target temperature, and preventing rebound hyperthermia.

Evaluating the burden of endogenous Cushing's syndrome using a web-based questionnaire and validated patient-reported outcome measures.

INTRODUCTION: Endogenous Cushing's syndrome (CS) is a rare endocrine condition caused by chronic oversecretion of cortisol, resulting in a diverse constellation of symptoms. This study examined the ongoing burden of illness (BOI), from the first appearance of symptoms through treatment, which is currently not well evaluated. METHODS: A quantitative, cross-sectional, web-enabled survey including 5 validated patient reported outcomes (PRO) measures was conducted in patients with CS who had been diagnosed ≥ 6 months prior and who had received ≥ 1 treatment for their endogenous CS at the time of the survey. RESULTS: Fifty-five patients participated in this study; 85% were women. The mean age was 43.4 ± 12.3 years (± standard deviation, SD). On average, respondents reported a 10-year gap between the first occurrence of symptoms and diagnosis; 80% underwent surgical treatment for CS. Respondents experienced symptoms on 16 days in a typical month, and their health-related quality of life was moderately impacted based on the CushingQoL score. Weight gain, muscle fatigue, and weakness were the most common symptoms and 69% percent of patients reported moderate or severe fatigue using the Brief Fatigue Inventory. Following treatment, the occurrence of most symptoms declined over time, although anxiety and pain did not significantly decrease. Overall, 38% of participants reported an annual average of 25 missed workdays due to CS symptoms. CONCLUSIONS: These results demonstrate a BOI in CS despite ongoing treatment and illustrate the need for interventions to address persistent symptoms, particularly weight gain, pain, and anxiety.

Surgical and Patient-Centered Outcomes of Open versus Arthroscopic Ganglion Cyst Excision: A Systematic Review.

Introduction As the popularity of wrist arthroscopy grows, it continues to prove useful in the treatment of ganglion cysts. Previous studies comparing an arthroscopic technique to traditional open excision have demonstrated generally equivalent results regarding complications and cyst recurrence. However, this systematic review compares the two treatment methods not only regarding cyst recurrence but also regarding patient-centered outcomes. Additionally, new studies in the available literature may allow for further analysis. Methods This systematic review identified 23 articles published between 2000 and 2021 that met inclusion criteria. Articles were assessed for quality, and reported cyst recurrence rates, patient satisfaction, patients' preoperative and postoperative pain, and complications associated with either open or arthroscopic excisions were pooled into open excision and arthroscopic excision groups for analysis. Results In total, 23 studies accounted for 1,670 cases. Pooled data for patient-centered outcomes indicated a significantly higher patient satisfaction rate (89.2 vs 85.6%, p < 0.001) and higher reported pain relief (69.5 vs. 66.7%, p = 0.011) associated with arthroscopic excision versus open excision. Recurrence rates were also significantly lower for the arthroscopic excision group (9.4 vs. 11.2%, p < 0.001). Overall, the complication rate was significantly lower for arthroscopic excision (7.5 vs. 10.7%, p < 0.001), but the complication profile distinctly differed between the two methods. Conclusions Both arthroscopic and open excision of dorsal wrist ganglions are viable treatment options. However, the results of this meta-analysis suggest benefits associated with the arthroscopic technique in both patient-centered outcomes and in traditional, surgical outcomes. This may prove advantageous as wrist arthroscopy becomes more common.

Detection of SARS-COV-2 by functionally imprinted micelles.

The near real-time detection of airborne particles-of-interest is needed for avoiding current/future threats. The incorporation of imprinted particles into a micelle-based electrochemical cell produced a signal when brought into contact with particle analytes (such as SARS-COV-2), previously imprinted onto the structure. Nanoamp scales of signals were generated from what may've been individual virus-micelle interactions. The system showed selectivity when tested against similar size and morphology particles. The technology was compatible with airborne aerosol sampling techniques. Overall, the application of imprinted micelle technology could provide near real-time detection methods to a host of possible analytes of interest in the field. Supplementary Information: The online version contains supplementary material available at 10.1557/s43579-022-00242-0.

Anion exchange and extraction chromatography tandem column isolation of zirconium-89 (89Zr) from cyclotron bombarded targets using an automated fluidic platform.

The long-lived positron emitter 89Zr is a highly promising nuclide employed in diagnostic Positron Emission Tomography (PET) imaging. Methods of radiochemical processing to obtain 89Zr for clinical use are traditionally performed with a single hydroxamate resin column. Herein, we present a tandem column purification method for the preparation of high-purity 89Zr from cyclotron bombarded natural Y metal foils. The primary column is a macroporous, strongly basic anion exchange resin on styrene divinylbenzene co-polymer. The secondary microcolumn, with an internal volume of 33 µL, is packed with an extraction chromatography resin (ExCR) loaded with di-(2-ethylhexyl)phosphoric acid (HDEHP). A condition of "inverted selectivity" is presented, wherein the 89Zr elution from the primary column is synonymous with the load condition on the secondary column. The ability to transfer 89Zr from one column to the next allows two sequential purification steps to be performed prior to the final elution of the 89Zr product. This approach assures delivery of high purity 89Zr. The tandem column purification process has been implemented into a prototype automated fluidic system. Optimization of the method is presented, followed by evaluation of the process using seven cyclotron bombarded Y metal foil targets. Once optimized, we found that 93.7 ± 2.3% of the 89Zr present in the foils was recovered in the secondary column elution fraction (0.8 M oxalic acid). Radiochromatograms of the product elution peaks enabled determination of full width at half-maximum (FWHM) and 89Zr collection yields as a function of volume. Because of the small size of the secondary microcolumn, a 89Zr product volume of ∼0.28 mL is reported, which provides a substantially increased nuclide concentration over traditional methods. Finally, we evaluated the transchelation of the resulting 89Zr oxalate product to deferoxamine mesylate (DFOM) salt. We observed effective specific activities (ESA) and bindable metals concentrations ([MB]) that exceed those reported by the traditional single hydroxamate column method.

Transcriptome-Wide Off-Target Effects of Steric-Blocking Oligonucleotides.

Steric-blocking oligonucleotides (SBOs) are short, single-stranded nucleic acids designed to modulate gene expression by binding to RNA transcripts and blocking access from cellular machinery such as splicing factors. SBOs have the potential to bind to near-complementary sites in the transcriptome, causing off-target effects. In this study, we used RNA-seq to evaluate the off-target differential splicing events of 81 SBOs and differential expression events of 46 SBOs. Our results suggest that differential splicing events are predominantly hybridization driven, whereas differential expression events are more common and driven by other mechanisms (including spurious experimental variation). We further evaluated the performance of in silico screens for off-target splicing events, and found an edit distance cutoff of three to result in a sensitivity of 14% and false discovery rate (FDR) of 99%. A machine learning model incorporating splicing predictions substantially improved the ability to prioritize low edit distance hits, increasing sensitivity from 4% to 26% at a fixed FDR of 90%. Despite these large improvements in performance, this approach does not detect the majority of events at an FDR <99%. Our results suggest that in silico methods are currently of limited use for predicting the off-target effects of SBOs, and experimental screening by RNA-seq should be the preferred approach.

Defining the Clinical, Emotional, Social, and Financial Burden of Congenital Athymia.

INTRODUCTION: Characterize the burden of illness in pediatric patients with congen̄ital athymia who were receiving supportive care. METHODS: This cross-sectional study of adult caregivers of patients with congenital athymia used both a quantitative survey and qualitative interviews. Caregivers of patients currently receiving supportive care responded to questions about the past 12 months and completed the parent proxy version of the Pediatric Quality of Life Inventory Generic instrument (PedsQL) for patients aged 2-4 years. For caregivers of patients who had received supportive care in the past, questions were asked about the period when they were receiving supportive care only. RESULTS: The sample included caregivers of 18 patients, 5 who were currently receiving supportive care and 13 who received investigational cultured human thymus tissue implantation before study enrollment and had received supportive care in the past. The impact of congenital athymia was substantial. Reports included the need to live in isolation (100% of respondents); caregiver emotional burden such as fear of death, infection, and worries about the future (100%); financial hardship (78%); and the inability to meet family/friends (72%). Patients had frequent and prolonged hospitalizations (78%) and had high utilization of procedures, medications, and home medical supplies. Caregiver-reported PedsQL scores for patients currently receiving supportive care (n = 4) indicated low health-related quality of life. CONCLUSIONS: Caregivers of patients with congenital athymia reported high clinical, emotional, social, and financial burden on patients and their families.

Economic burden of congenital athymia in the United States for patients receiving supportive care during the first 3 years of life.

AIMS: Congenital athymia is an ultra-rare pediatric condition characterized by the lack of thymus in utero and the naïve T cells critical for infection defense and immune regulation. Patients with congenital athymia receive supportive care to minimize and treat infections, autoimmune phenomena, and autologous graft-versus-host disease (aGVHD) manifestations, but historically, die within the first 3 years of life with supportive care only. We estimated the healthcare resource utilization and economic burden of supportive care over patients' first 3 years of life in the United States. METHODS: A medical chart audit by the treating physician was used to collect patient data from birth to age 3 on clinical manifestations associated with congenital athymia (clinical manifestations due to underlying syndromic conditions excluded). Using costs and charges from publicly available sources, the total economic burden of direct medical costs and charges for the first 3 years of life (considered "lifetime" for patients receiving supportive care) and differences in economic burden between patients with higher and lower inpatient hospitalization durations were estimated. RESULTS: All patients (n = 10) experienced frequent infections and aGVHD manifestations; 40% experienced ≥1 episode of sepsis, and 20% had recurrent sepsis episodes annually. The estimated mean 3-year economic burden per patient was US$5,534,121 (2020 US dollars). The annual mean inpatient hospitalization duration was 150.6 days. Inpatient room charges accounted for 79% of the economic burden, reflecting the high costs of specialized care settings required to prevent infection, including isolation. Patients with high inpatient utilization (n = 5; annual mean inpatient hospitalization duration, 289.6 days) had an estimated 3-year economic burden of US$9,926,229. LIMITATIONS: The total economic burden may not be adequately represented due to underestimation of some direct costs or overestimation of others. CONCLUSIONS: Current treatment of patients with congenital athymia (supportive care) presents a high economic burden to the healthcare system.

The Impact of Undetected In Vitro Hemolysis or Sample Contamination on Patient Care and Outcomes in Point-of-Care Testing: A Retrospective Study.

BACKGROUND: Point-of-care (POC) testing is an integral diagnostic component in clinical settings like the emergency department (ED). However, most POC testing devices are unable to detect endogenous interferents such as hemolysis, which typically occurs during sample collection and handling and can falsely increase measured potassium (pseudohyperkalemia), a phenomenon we hypothesized may significantly impact patient care. METHODS: In this retrospective study, we evaluated 100 unique admissions to the Oregon Health & Science University ED, presenting with elevated potassium measured at the POC. To evaluate whether in vitro hemolysis had occurred, POC test results were compared to repeat testing of the original specimen, or other specimens tested within 90 minutes in the Core laboratory. Review of associated Electronic Health Records determined whether elevated potassium initially measured using the POC analyzer was real, or due to in vitro hemolysis or contamination, and whether pseudohyperkalemia impacted patient management or care. RESULTS: Of the 100 admissions with hyperkalemia measured using a POC analyzer, 40% were found to have pseudohyperkalemia due to hemolysis or contamination. Of these 40 patients, 6 experienced repeated testing, and an additional 5 were noted to have altered patient management, specifically due to pseudohyperkalemia. CONCLUSIONS: This study demonstrates the incidence of in vitro hemolysis, which is unknown to the POC operator, is high in patients who show an elevated potassium as measured at the POC. Furthermore, in vitro hemolysis can significantly impact patient management, suggesting that minimizing the incidence of unrecognized hemolysis will benefit hospital efficiency, decrease waste, and improve patient care.

ATP7B variant c.1934T > G p.Met645Arg causes Wilson disease by promoting exon 6 skipping.

Wilson disease is a recessive genetic disorder caused by pathogenic loss-of-function variants in the ATP7B gene. It is characterized by disrupted copper homeostasis resulting in liver disease and/or neurological abnormalities. The variant NM_000053.3:c.1934T > G (Met645Arg) has been reported as compound heterozygous, and is highly prevalent among Wilson disease patients of Spanish descent. Accordingly, it is classified as pathogenic by leading molecular diagnostic centers. However, functional studies suggest that the amino acid change does not alter protein function, leading one ClinVar submitter to question its pathogenicity. Here, we used a minigene system and gene-edited HepG2 cells to demonstrate that c.1934T > G causes ~70% skipping of exon 6. Exon 6 skipping results in frameshift and stop-gain, leading to loss of ATP7B function. The elucidation of the mechanistic effect for this variant resolves any doubt about its pathogenicity and enables the development of genetic medicines for restoring correct splicing.

Gas-phase molybdenum-99 separation from uranium dioxide by fluoride volatility using nitrogen trifluoride.

Production of the important 99mTc medical isotope parent, molybdenum-99 (99Mo), via the fissioning of high- and low-enriched uranium (HEU/LEU) targets followed by target dissolution in acid and solution-phase purification of 99Mo is time-consuming, generates quantities of corrosive radioactive waste, and can result in the release of an array of radionuclides to the atmosphere. An alternative 99Mo purification method has been devised that has the potential to alleviate many of these issues. Herein, we demonstrate the feasibility of a rapid Mo/Tc gas-phase separation from UO2. The results indicate that volatile [99Mo]Mo can be captured downstream of the reacted solid mixture on a column bed (trap) of alumina; the majority of the captured [99Mo]Mo can be subsequently eluted from the alumina trap with a few milliliters of water. >1.0 × 105 single pass decontamination of U and the collected [99Mo]Mo product is demonstrated. This simple thermo-fluorination technique has the potential to provide a rapid methodology for routine 99Mo production.

Perspectives On Blood-Based Point-Of-Care Diagnostics.

BACKGROUND: Point of Care (POC) diagnostics are an essential component of modern medicine and are employed in a variety of clinical disciplines to improve patient outcomes and provider efficiency. Despite these benefits, there are aspects of POC testing which may still hold room for improvement. In the present study, a group of healthcare professionals familiar with different facets of blood-based POC testing provided their perspectives on the benefits and challenges of POC testing within their respective fields. MATERIALS AND METHODS: The study was conducted from April to June 2019, in Colorado, United States of America. Five healthcare professionals, each working in a distinct field (anesthesiology, nursing, emergency medicine, trauma surgery, and POC management) were interviewed. Results from each of the interviews were transcribed as qualitative perspectives on POC diagnostics. DISCUSSION: The general consensus among participants in this study is that POC testing is tremendously beneficial, providing rapid test results, increased access to diagnostics, and improvements in hospital efficiency. However, significant challenges remain in blood-based POC diagnostics, particularly in maintaining sample quality, due to the fact that devices used for sample acquisition and handling are not designed for POC. This raises the possibility for interferents like hemolysis to occur, which may alter diagnostic results. Errors in POC diagnostics, whether due to sample, operator, or instrument error, may cause providers to lose confidence in the test. This lack of confidence can lead to duplicate testing and delayed patient diagnoses. CONCLUSION: The perspectives presented in this study suggest there is a significant need for improvement in the pre-analytical phase of POC testing, and that current practice employs specimen collection technology not designed for POC. Therefore, one hypothesis is that the introduction of a collection device designed specifically for POC could reduce pre-analytical errors, standardize sample quality, improve efficiency, and further benefit patient care.

Development of an autonomous solvent extraction system to isolate astatine-211 from dissolved cyclotron bombarded bismuth targets.

Cyclotron-produced astatine-211 (211At) shows tremendous promise in targeted alpha therapy (TAT) applications due to its attractive half-life and its 100% α-emission from nearly simultaneous branched alpha decay. Astatine-211 is produced by alpha beam bombardment of naturally monoisotopic bismuth metal (209Bi) via the (α, 2n) reaction. In order to isolate the small mass of 211At (specific activity = 76 GBq·µg-1) from several grams of acid-dissolved Bi metal, a manual milliliter-scale solvent extraction process using diisopropyl ether (DIPE) is routinely performed at the University of Washington. As this process is complex and time consuming, we have developed a fluidic workstation that can perform the method autonomously. The workstation employs two pumps to concurrently deliver the aqueous and organic phases to a mixing tee and in-line phase mixer. The mixed phases are routed to a phase settling reservoir, where they gravity settle. Finally, each respective phase is withdrawn into its respective pump. However, development of a phase boundary sensor, placed in tandem with the phase settling reservoir, was necessary to communicate to the system when withdrawal of the denser aqueous phase was complete (i.e., the intersection of the two phases was located). The development and optimization of the autonomous solvent extraction system is described, and the 211At yields from several ~1.1 GBq-level 211At processing runs are reported.

Manipulation of mass transport rates using bead-in-a-tube method.

In ultralow Pu analyses, the gold standard is thermal ionization mass spectrometry (TIMS), which requires pure sources to achieve its performance. This purity is achieved through step-wise purifications. In this work single, anion-exchange beads were trapped in the tubing to allow for dynamic solution cycling over the surface of the beads to improve the rates of metal complex uptake. Rates of Pu sorption on single ∼900 µm SIR-1200 and ∼620 µm Reillex-HPQ beads were determined for single beads trapped in a tube with syringe pump driven dynamic solution cycling over the bead, improving sorption and desorption rates. A static control was used as a comparison. Using 238Pu to enable facile activity-based measurements, rates were determined by measuring the residual Pu after contact with beads using liquid scintillation analysis (LSA) for fixed periods of time. Syringe pump driven dynamic solution cycling results in ∼5 and ∼15-fold improvements in the sorption rates for SIR-1200 and Reillex-HPQ. Impacts on desorption were also examined.

Tandem column isolation of zirconium-89 from cyclotron bombarded yttrium targets using an automated fluidic platform: Anion exchange to hydroxamate resin columns.

The development of a tandem column purification method for the preparation of high-purity 89Zr(IV) oxalate is presented. The primary column was a macroporous strongly basic anion exchange resin on styrene divinylbenzene co-polymer. The secondary column, with an internal volume of 33 µL, was packed with hydroxamate resin. A condition of inverted selectivity was developed, whereby the 89Zr eluent solution for the primary column is equivalent to the 89Zr load solution for the secondary column. The ability to transfer 89Zr from one column to the next allows two sequential column clean-up methods to be performed prior to the final elution of the 89Zr(IV) oxalate. This approach assures delivery of high purity 89Zr product and assures a 89Zr product that is eluted in a substantially smaller volume than is possible when using the traditionally-employed single hydroxamate resin column method. The tandem column purification process has been implemented into a prototype automated fluidic system. The system is configured with on-line gamma detection so column effluents can be monitored in near-real time. The automated method was tested using seven cyclotron bombarded Y foil targets. It was found that 95.1 ±â€¯1.3% of the 89Zr present in the foils was recovered in the secondary column elution fraction. Furthermore, elution peak analysis of several 89Zr elution profile radiochromatograms made possible the determination of 89Zr recovery as a function of volume; a 89Zr product volume that contains 90% of the mean secondary column elution peak can be obtained in 0.29 ±â€¯0.06 mL (representing 86 ±â€¯5% of the 89Zr activity in the target). This product volume represents a significant improvement in radionuclide product concentration over the predominant method used in the field. In addition to the reduced 89Zr product elution volume, titrations of the 89Zr product with deferoxamine mesylate salt across two preparatory methods resulted in mean effective specific activity (ESA) values of 279 and 340 T Bq·mmole-1 and mean bindable metals concentrations ([MB]) of 13.5 and 16.7 nmole·g-1. These ESA and [MB] values infer that the 89Zr(IV) oxalate product resulting from this tandem column isolation method has the highest purity reported to date.

Critical differences in drug metabolic properties of human hepatic cellular models, including primary human hepatocytes, stem cell derived hepatocytes, and hepatoma cell lines.

Primary human hepatocytes (PHH), HepaRG™, HepG2, and two sources of induced pluripotent stem cell (iPSC) derived hepatocytes were characterized regarding gene expression and function of key hepatic proteins, important for the metabolic fate of drugs. The gene expression PCA analysis showed a distance between the two iPSC derived hepatocytes as well as the HepG2 and HepaRG™ cells to the three PHH donors and PHH pool, which were clustered more closely together. Correlation-based hierarchical analysis clustered HepG2 close to the stem cell derived hepatocytes both when the expression of 91 genes related to liver function or only cytochrome P450 (P450) genes were analyzed indicating the non-liver feature and a similar low P450 profile in these cell models. The specific P450 activities and the metabolic pattern of well-characterized drug substances in the cell models demonstrated that iPSC derived hepatocytes had modest levels of CYP3A and CYP2C9, while CYP1A2, 2B6, 2C8, 2C9, 2C19, and 2D6 were barely detectable. High expression of several extrahepatic P450s such as CYP1A1 and 1B1 detected in the stem cell derived hepatocytes may have significant effects on metabolite profiles. However, one of the iPSC derived hepatocytes demonstrated significant combined P450 and conjugating enzyme activity of certain drugs. HepaRG™ cells showed many metabolic properties similar to PHHs and will in many respects be a good model in studies of metabolic pathways and induction of drug metabolism whereas there is still ground to cover before iPSC derived hepatocytes will be seen as a substitute to PHH in drug metabolism studies.