Metabolic and Proteomic Divergence Is Present in Circulating Monocytes and Tissue-Resident Macrophages from Berkeley Sickle Cell Anemia and ß-Thalassemia Mice.

Sickle cell disease and ß-thalassemia represent hemoglobinopathies arising from dysfunctional or underproduced ß-globin chains, respectively. In both diseases, red blood cell injury and anemia are the impetus for end organ injury. Because persistent erythrophagocytosis is a hallmark of these genetic maladies, it is critical to understand how macrophage phenotype polarizations in tissue compartments can inform on disease progression. Murine models of sickle cell disease and ß-thalassemia allow for a basic understanding of the mechanisms and provide for translation to human disease. A multi-omics approach to understanding the macrophage metabolism and protein changes in two murine models of ß-globinopathy was performed on peripheral blood mononuclear cells as well as spleen and liver macrophages isolated from Berkley sickle cell disease (Berk-ss) and heterozygous B1/B2 globin gene deletion (Hbbth3/+) mice. The results from these experiments revealed that the metabolome and proteome of macrophages are polarized to a distinct phenotype in Berk-ss and Hbbth3/+ compared with each other and their common-background mice (C57BL6/J). Further, spleen and liver macrophages revealed distinct disease-specific phenotypes, suggesting that macrophages become differentially polarized and reprogrammed within tissue compartments. We conclude that tissue recruitment, polarization, and metabolic and proteomic reprogramming of macrophages in Berk-ss and Hbbth3/+ mice may be relevant to disease progression in other tissue.

Moderate hypoxia induces metabolic divergence in circulating monocytes and tissue resident macrophages from Berkeley sickle cell anemia mice.

Introduction: Human and murine sickle cell disease (SCD) associated pulmonary hypertension (PH) is defined by hemolysis, nitric oxide depletion, inflammation, and thrombosis. Further, hemoglobin (Hb), heme, and iron accumulation are consistently observed in pulmonary adventitial macrophages at autopsy and in hypoxia driven rodent models of SCD, which show distribution of ferric and ferrous Hb as well as HO-1 and ferritin heavy chain. The anatomic localization of these macrophages is consistent with areas of significant vascular remodeling. However, their contributions toward progressive disease may include unique, but also common mechanisms, that overlap with idiopathic and other forms of pulmonary hypertension. These processes likely extend to the vasculature of other organs that are consistently impaired in advanced SCD. Methods: To date, limited information is available on the metabolism of macrophages or monocytes isolated from lung, spleen, and peripheral blood in humans or murine models of SCD. Results: Here we hypothesize that metabolism of macrophages and monocytes isolated from this triad of tissue differs between Berkley SCD mice exposed for ten weeks to moderate hypobaric hypoxia (simulated 8,000 ft, 15.4% O2) or normoxia (Denver altitude, 5000 ft) with normoxia exposed wild type mice evaluated as controls. Discussion: This study represents an initial set of data that describes the metabolism in monocytes and macrophages isolated from moderately hypoxic SCD mice peripheral lung, spleen, and blood mononuclear cells.

Extracellular Vesicle Size Reveals Cargo Specific to Coagulation and Inflammation in Pediatric and Adult Sickle Cell Disease.

Aberrant coagulation in sickle cell disease (SCD) is linked to extracellular vesicle (EV) exposure. However, there is no consensus on the contributions of small EVs (SEVs) and large EVs (LEVs) toward underlying coagulopathy or on their molecular cargo. The present observational study compared the thrombin potential of SEVs and LEVs isolated from the plasma of stable pediatric and adult SCD patients. Further, EV lipid and protein contents were analyzed to define markers consistent with activation of thrombin and markers of underlying coagulopathy. Results suggested that LEVs-but not SEVs-from pediatrics and adults similarly enhanced phosphatidylserine (PS)-dependent thrombin generation, and cell membrane procoagulant PS (18:0;20:4 and 18:0;18:1) were the most abundant lipids found in LEVs. Further, LEVs showed activated coagulation in protein pathway analyses, while SEVs demonstrated high levels of cholesterol esters and a protein pathway analysis that identified complement factors and inflammation. We suggest that thrombin potential of EVs from both stable pediatric and adult SCD patients is similarly dependent on size and show lipid and protein contents that identify underlying markers of coagulation and inflammation.

Evaluating the Discriminatory Ability of the Sickle Cell Data Collection Program's Administrative Claims Case Definition in Identifying Adults With Sickle Cell Disease: Validation Study.

BACKGROUND: Sickle cell disease (SCD) was first recognized in 1910 and identified as a genetic condition in 1949. However, there is not a universal clinical registry that can be used currently to estimate its prevalence. The Sickle Cell Data Collection (SCDC) program, funded by the Centers for Disease Control and Prevention, funds state-level grantees to compile data within their states from various sources including administrative claims to identify individuals with SCD. The performance of the SCDC administrative claims case definition has been validated in a pediatric population with SCD, but it has not been tested in adults. OBJECTIVE: The objective of our study is to evaluate the discriminatory ability of the SCDC administrative claims case definition to accurately identify adults with SCD using Medicaid insurance claims data. METHODS: Our study used Medicaid claims data in combination with hospital-based medical record data from the Alabama, Georgia, and Wisconsin SCDC programs to identify individuals aged 18 years or older meeting the SCDC administrative claims case definition. In order to validate this definition, our study included only those individuals who were identified in both Medicaid's and the partnering clinical institution's records. We used clinical laboratory tests and diagnostic algorithms to determine the true SCD status of this subset of patients. Positive predictive values (PPV) are reported overall and by state under several scenarios. RESULTS: There were 1219 individuals (354 from Alabama and 865 from Georgia) who were identified through a 5-year time period. The 5-year time period yielded a PPV of 88.4% (91% for data from Alabama and 87% for data from Georgia), when only using data with laboratory-confirmed (gold standard) cases as true positives. With a narrower time period (3-year period) and data from 3 states (Alabama, Georgia, and Wisconsin), a total of 1432 individuals from these states were included in our study. The overall 3-year PPV was 89.4% (92%, 93%, and 81% for data from Alabama, Georgia, and Wisconsin, respectively) when only considering laboratory-confirmed cases as true cases. CONCLUSIONS: Adults identified as having SCD from administrative claims data based on the SCDC case definition have a high probability of truly having the disease, especially if those hospitals have active SCD programs. Administrative claims are thus a valuable data source to identify adults with SCD in a state and understand their epidemiology and health care service usage.

A randomized clinical trial of the efficacy and safety of rivipansel for sickle cell vaso-occlusive crisis.

The efficacy and safety of rivipansel, a predominantly E-selectin antagonist, were studied in a phase 3, randomized, controlled trial for vaso-occlusive crisis (VOC) requiring hospitalization (RESET). A total of 345 subjects (204 adults and 141 children) were randomized and 320 were treated (162 with rivipansel, 158 with placebo) with an IV loading dose, followed by up to 14 additional 12-hourly maintenance doses of rivipansel or placebo, in addition to standard care. Rivipansel was similarly administered during subsequent VOCs in the Open-label Extension (OLE) study. In the full analysis population, the median time to readiness for discharge (TTRFD), the primary end point, was not different between rivipansel and placebo (-5.7 hours, P = .79; hazard ratio, 0.97), nor were differences seen in secondary end points of time to discharge (TTD), time to discontinuation of IV opioids (TTDIVO), and cumulative IV opioid use. Mean soluble E-selectin decreased 61% from baseline after the loading dose in the rivipansel group, while remaining unchanged in the placebo group. In a post hoc analysis, early rivipansel treatment within 26.4 hours of VOC pain onset (earliest quartile of time from VOC onset to treatment) reduced median TTRFD by 56.3 hours, reduced median TTD by 41.5 hours, and reduced median TTDIVO by 50.5 hours, compared with placebo (all P < .05). A similar subgroup analysis comparing OLE early-treatment with early-treatment RESET placebo showed a reduction in TTD of 23.1 hours (P = .062) and in TTDIVO of 30.1 hours (P = .087). Timing of rivipansel administration after pain onset may be critical to achieving accelerated resolution of acute VOC. Trial Registration: Clinicaltrials.gov, NCT02187003 (RESET), NCT02433158 (OLE).

Evaluation of a patient specific, targeted-intensity pharmacologic thromboprophylaxis protocol in hospitalized patients with COVID-19.

Patients with COVID-19 are at higher risk of thrombosis due to the inflammatory nature of their disease. A higher-intensity approach to pharmacologic thromboprophylaxis may be warranted. The objective of this retrospective cohort study was to determine if a patient specific, targeted-intensity pharmacologic thromboprophylaxis protocol incorporating severity of illness, weight, and biomarkers decreased incidence of thrombosis in hospitalized patients with COVID-19. Included patients were hospitalized with COVID-19 and received thromboprophylaxis within 48 h of admission. Exclusion criteria included receipt of therapeutic anticoagulation prior to or within 24 h of admission, history of heparin-induced thrombocytopenia, extracorporeal membrane oxygenation, pregnancy, or incarceration. Per-protocol patients received thromboprophylaxis according to institutional protocol involving escalated doses of anticoagulants based upon severity of illness, total body weight, and biomarker thresholds. The primary outcome was thrombosis. Secondary outcomes included major bleeding, mortality, and identification of risk factors for thrombosis. Of 1189 patients screened, 803 were included in the final analysis. The median age was 54 (42-65) and 446 (55.5%) were male. Patients in the per-protocol group experienced significantly fewer thrombotic events (4.4% vs. 10.7%, p = 0.002), less major bleeding (3.1% vs. 9.6%, p < 0.001), and lower mortality (6.3% vs. 11.8%, p = 0.02) when compared to patients treated off-protocol. Significant predictors of thrombosis included mechanical ventilation and male sex. Post-hoc regression analysis identified mechanical ventilation, major bleeding, and D-dimer ≥ 1500 ng/mL FEU as significant predictors of mortality. A targeted pharmacologic thromboprophylaxis protocol incorporating severity of illness, body weight, and biomarkers appears effective and safe for preventing thrombosis in patients with COVID-19.

Metal forms and dynamics in urban stormwater runoff: New insights from diffusive gradients in thin-films (DGT) measurements.

Stormwater runoff typically contains significant quantities of metal contaminants that enter urban waterways over short durations and represent a potential risk to water quality. The origin of metals within the catchment and processes that occur over the storm can control the partitioning of metals between a range of different forms. Understanding the fraction of metals present in a form that is potentially bioavailable to aquatic organisms is useful for environmental risk assessment. To help provide this information, the forms and dynamics of metal contaminants in an urban system were assessed across a storm. Temporal patterns in the concentration of metals in dissolved and particulate (total suspended solids; TSS) forms were assessed from water samples, and diffusive gradients in thin-films (DGTs) were deployed to measure the DGT-labile time-integrated metal concentration. Results indicate that the concentrations of dissolved and TSS-associated metals increased during the storm, with the metals Al, Cd, Co, Cu, Pb and Zn representing the greatest concern relative to water quality guideline values (GVs). The portion of labile metal as measured by DGT devices indicated that during the storm a substantial fraction (∼98%) of metals were complexed and pose a lower risk of acute toxicity to aquatic organisms. Comparison of DGT results to GVs indicate that current GVs are likely quite conservative when assessing stormwater pollution risks with regards to metal contaminants. This study provides valuable insight into the forms and dynamics of metals in an urban system receiving stormwater inputs and assists with the development of improved approaches for the assessment of short-term, intermittent discharge events.

Murine models of sickle cell disease and beta-thalassemia demonstrate pulmonary hypertension with distinctive features.

Sickle cell anemia and ß-thalassemia intermedia are very different genetically determined hemoglobinopathies predisposing to pulmonary hypertension. The etiologies responsible for the associated development of pulmonary hypertension in both diseases are multi-factorial with extensive mechanistic contributors described. Both sickle cell anemia and ß-thalassemia intermedia present with intra and extravascular hemolysis. And because sickle cell anemia and ß-thalassemia intermedia share features of extravascular hemolysis, macrophage iron excess and anemia we sought to characterize the common features of the pulmonary hypertension phenotype, cardiac mechanics, and function as well as lung and right ventricular metabolism. Within the concept of iron, we have defined a unique pulmonary vascular iron accumulation in lungs of sickle cell anemia pulmonary hypertension patients at autopsy. This observation is unlike findings in idiopathic or other forms of pulmonary arterial hypertension. In this study, we hypothesized that a common pathophysiology would characterize the pulmonary hypertension phenotype in sickle cell anemia and ß-thalassemia intermedia murine models. However, unlike sickle cell anemia, ß-thalassemia is also a disease of dyserythropoiesis, with increased iron absorption and cellular iron extrusion. This process is mediated by high erythroferrone and low hepcidin levels as well as dysregulated iron transport due transferrin saturation, so there may be differences as well. Herein we describe common and divergent features of pulmonary hypertension in aged Berk-ss (sickle cell anemia) and Hbbth/3+ (intermediate ß-thalassemia) mice and suggest translational utility as proof-of-concept models to study pulmonary hypertension therapeutics specific to genetic anemias.

Evidence supporting a role for circulating macrophages in the regression of vascular remodeling following sub-chronic exposure to hemoglobin plus hypoxia.

Macrophages are a heterogeneous population with both pro- and anti-inflammatory functions play an essential role in maintaining tissue homeostasis, promoting inflammation under pathological conditions, and tissue repair after injury. In pulmonary hypertension, the M1 phenotype is more pro-inflammatory compared to the M2 phenotype, which is involved in tissue repair. The role of macrophages in the initiation and progression of pulmonary hypertension is well studied. However, their role in the regression of established pulmonary hypertension is not well known. Rats chronically exposed to hemoglobin (Hb) plus hypoxia (HX) share similarities to humans with pulmonary hypertension associated with hemolytic disease, including the presence of a unique macrophage phenotype surrounding distal vessels that are associated with vascular remodeling. These lung macrophages are characterized by high iron content, HO-1, ET-1, and IL-6, and are recruited from the circulation. Depletion of macrophages in this model prevents the development of pulmonary hypertension and vascular remodeling. In this study, we specifically investigate the regression of pulmonary hypertension over a four-week duration after rats were removed from Hb + HX exposure with and without gadolinium chloride administration. Withdrawal of Hb + HX reversed systolic pressures and right ventricular function after Hb + Hx exposure in four weeks. Our data show that depleting circulating monocytes/macrophages during reversal prevents complete recovery of right ventricular systolic pressure and vascular remodeling in this rat model of pulmonary hypertension at four weeks post exposure. The data presented offer a novel insight into the role of macrophages in the processes of pulmonary hypertension regression in a rodent model of Hb + Hx-driven disease.

Hemopexin dosing improves cardiopulmonary dysfunction in murine sickle cell disease.

Hemopexin (Hpx) is a crucial defense protein against heme liberated from degraded hemoglobin during hemolysis. High heme stress creates an imbalance in Hpx bioavailability, favoring heme accumulation and downstream pathophysiological responses leading to cardiopulmonary disease progression in sickle cell disease (SCD) patients. Here, we evaluated a model of murine SCD, which was designed to accelerate red blood cell sickling, pulmonary hypertension, right ventricular dysfunction, and exercise intolerance by exposure of the mice to moderate hypobaric hypoxia. The sequence of pathophysiology in this model tracks with circulatory heme accumulation, lipid oxidation, extensive remodeling of the pulmonary vasculature, and fibrosis. We hypothesized that Hpx replacement for an extended period would improve exercise tolerance measured by critical speed as a clinically meaningful therapeutic endpoint. Further, we sought to define the effects of Hpx on upstream cardiopulmonary function, histopathology, and tissue oxidation. Our data shows that tri-weekly administrations of Hpx for three months dose-dependently reduced heme exposure and pulmonary hypertension while improving cardiac pressure-volume relationships and exercise tolerance. Furthermore, Hpx administration dose-dependently attenuated pulmonary fibrosis and oxidative modifications in the lung and myocardium of the right ventricle. Observations in our SCD murine model are consistent with pulmonary vascular and right ventricular pathology at autopsy in SCD patients having suffered from severe pulmonary hypertension, right ventricular dysfunction, and sudden cardiac death. This study provides a translational evaluation supported by a rigorous outcome analysis demonstrating therapeutic proof-of-concept for Hpx replacement in SCD.

Surprising Pseudogobius: Molecular systematics of benthic gobies reveals new insights into estuarine biodiversity (Teleostei: Gobiiformes).

Snubnose gobies (genus Pseudogobius: Gobionellinae) are ubiquitous to, and important components of, estuarine ecosystems of the Indo-west Pacific. These small benthic fishes occur in freshwater, brackish and marine habitats such as mangroves, sheltered tide pools and lowland streams, and represent a model group for understanding the biodiversity and biogeography of estuarine fauna. To develop the species-level framework required for a concurrent morphological taxonomic appraisal, we undertook thorough sampling around the extensive Australian coastline, referenced to international locations, as part of a molecular systematic review using both nuclear and mitochondrial markers. The results indicate that while there are currently eight recognised species, the true diversity is close to double this, with a hotspot of endemism located in Australia. Complicated patterns were observed in southern Australia owing to two differing zones of introgression/admixture. Key drivers of diversity in the group appear to include plate tectonics, latitude, and historic barriers under glacial maxima, where an interplay between ready dispersal and habitat specialisation has led to regional panmixia but frequent geographic compartmentalisation within past and present landscapes. The findings have significant implications for biodiversity conservation, coastal and estuarine development, the basic foundations of field ecology, and for applied use such as in biomonitoring.

Effect of short-term dietary exposure on metal assimilation and metallothionein induction in the estuarine fish Pseudogobius sp.

Metals introduced into the urban aquatic environment through anthropogenic activities have the potential to accumulate in organisms via multiple uptake routes. Understanding the impact different routes have on metal accumulation is important for the continued management of these ecosystems, where current water quality guidelines (WQGs) tend to be derived from aqueous metal exposure tests. In this study, the estuarine fish Pseudogobius sp. was exposed to a mixture of cadmium (Cd) and zinc (Zn) radiotracers dissolved in water or present in experimental food. Metal-spiked food was presented to fish as a single 'pulse-chase' feed or as three consecutive feeds, where the cumulative metal dose provided by both treatments was equal. Fish did not accumulate either metal from water, even after the length of exposure was increased from 12 h to 36 h. Fish did accumulate metals from diet and the assimilation efficiency (AE) was low following a single feed (12% for both Cd and Zn). Following multiple feeds fish displayed a significantly higher AE for zinc only, suggesting that fish are susceptible to retention of dietary Zn over an extended time period albeit at lower daily loadings. The final body burden and efflux rate did not differ between feeding regimes. Tissue accumulation of Cd and Zn indicated metal specific distribution. The gastro-intestinal (GI) tract contained >90% of total Cd body burden, whilst the carcass accounted for the majority (70-88%) of Zn body burden. There was significant induction of the biomarker metallothionein (MT) in the GI tract. These results demonstrate the differences in Cd and Zn metal uptake characteristics in this estuarine fish species, and how feeding frequency and metal loading of food may influence assimilation. This study highlights the importance of considering the inclusion of dietary exposures in WQG frameworks.

Improving Preventive Care for Children With Sickle Cell Anemia: A Quality Improvement Initiative.

Sickle cell disease is a complex chronic disorder associated with increased morbidity and early mortality. The Pediatric Quality Measures Program has developed new sickle cell-specific quality measures focused on hydroxyurea (HU) counseling and annual transcranial Doppler (TCD) screening; however, these measures have not been used in a clinical setting to inform quality improvement (QI) efforts. METHODS: From 2017 to 2018, 9 sickle cell subspecialty clinics from the Pacific Sickle Cell Regional Collaborative conducted a year-long QI collaborative focused on improving the percentage of patients with HU counseling and TCD screening based on the new quality measures. After an initial kick-off meeting, the 9 sites participated in monthly conference calls. We used run charts annotated with plan-do-study-act cycle activities to track each site's monthly progress and the overall mean percentage for the entire collaborative. RESULTS: There was an overall improvement in the aggregate HU counseling from 85% to 98% (P < 0.01). For TCD screening, referral frequency changed from 85% to 90% (P = 0.76). For both measures, the variation in frequencies decreased over the year. CONCLUSION: Over 1 year, we found that a regional QI collaborative increased HU counseling. Although referral for TCD screening increased, there was no overall change in TCD completion. Overall, this QI report's findings can help clinicians adopt and implement these quality measures to improve outcomes in children.

Ovarian stimulation for fertility preservation in an oncology patient with etonogestrel implant in place.

PURPOSE: To describe a case of a young woman who presented for fertility preservation and underwent ovarian stimulation with an etonogestrel implant in place. METHODS: A 24-year old, gravida 0, with an etonogestrel implant and newly diagnosed lower extremity sarcoma and DVT desiring oocyte cryopreservation prior to adjuvant chemotherapy and radiation. To avoid delay in her oncologic care and allow for continued use of contraception post-retrieval, the patient underwent controlled ovarian hyperstimulation (COH) without removal of the etonogestrel implant. RESULTS: Baseline labs included follicle-stimulating hormone 9 mIU/mL, luteinizing hormone 4.9 mIU/mL, estradiol 42 pg/mL, anti-Müllerian hormone 5.1 ng/mL, and antral follicle count greater than 40. The patient was placed on an antagonist protocol and stimulated with 125 IU Gonal-F and 75 IU Menopur. She received a total of 12 days of gonadotropin stimulation. On the day of trigger, her estradiol was 1472 pg/mL, lead follicle 21.5 mm with a total of 25 follicles measured > 12 mm. She was triggered with 5000 U hCG. She had a total of 23 oocytes retrieved, 17 of which were metaphase II and vitrified. CONCLUSIONS: COH and successful oocyte cryopreservation can be achieved in patients with an etonogestrel implant in situ without apparent detrimental effects to oocyte yield or maturity. Due to the etonogestrel implant's inhibitory effects on LH, it is recommended to use an hCG trigger for final oocyte maturation.

A trial of antithrombotic therapy in patients with refractory migraine and antiphospholipid antibodies: A retrospective study of 75 patients.

OBJECTIVE: It has been reported that patients with antiphospholipid antibodies (aPL) and refractory migraine may experience symptomatic improvement with antithrombotic therapy, but this phenomenon has not been well studied. This study was undertaken to detail the response to trials of antithrombotic therapy in these patients. METHODS: This is a retrospective study of 75 patients with refractory migraine and aPL who were given a 2-4 week trial of aspirin, clopidogrel and/or anticoagulation. Major response was defined as 50-100% improvement in frequency and/or severity of migraine; minor response: 25-49% improvement; no response: <25% improvement. RESULTS: 66 patients were given a trial of aspirin: 47% responded (21% major); 60 patients were given a trial of clopidogrel: 83% responded (67% major); and 34 patients were given a trial of anticoagulation (usually apixaban): 94% responded (85% major). The response rate to any anti-thrombotic therapy was 89% (83% major). Many patients also noted improvement in non-headache symptoms. No patient experienced stroke. There was no major bleeding during any 2-4 week treatment trial and only 3 of 69 patients maintained on an antithrombotic regimen for a median follow up of 29.9 months (5-100) experienced major bleeding. CONCLUSIONS: There was a high rate of symptomatic response to antithrombotic therapy in this context and long-term follow up suggested an individualized symptom-derived antithrombotic regimen may be associated with a low bleeding risk. Our data support consideration of a 2-4 week trial of antithrombotic therapy, usually starting with antiplatelet therapy, in aPL-positive patients with refractory migraine, particularly if other treatment options have been exhausted. As a retrospective study, our data provide only Class IV level of evidence, but they suggest randomized controlled trials are warranted to validate these encouraging findings.

Newborn Screening Practices and Alpha-Thalassemia Detection - United States, 2016.

Alpha-thalassemia comprises a group of inherited disorders in which alpha-hemoglobin chain production is reduced. Depending on the genotype, alpha-thalassemia results in moderate to profound anemia, hemolysis, growth delays, splenomegaly, and increased risk for thromboembolic events; certain patients might require chronic transfusions. Although alpha-thalassemia is not a core condition of the United States Recommended Uniform Screening Panel* for state newborn screening programs, methodologies used by some newborn screening programs to detect sickle cell disease, which is a core panel condition, also detect a quantitative marker of alpha-thalassemia, hemoglobin (Hb) Bart's, an abnormal type of hemoglobin. The percentage of Hb Bart's detected correlates with alpha-thalassemia severity. The Association of Public Health Laboratories' Hemoglobinopathy Workgroup conducted a survey of state newborn screening programs' alpha-thalassemia screening methodologies and reporting and follow-up practices. Survey findings indicated that 41 of 44 responding programs (93%) report some form of alpha-thalassemia results and 57% used a two-method screening protocol. However, the percentage of Hb Bart's used for thalassemia classification, the types of alpha-thalassemia reported, and the recipients of this information varied widely. These survey findings highlight the opportunity for newborn screening programs to revisit their policies as they reevaluate their practices in light of the recently released guideline from the Clinical and Laboratory Standards Institute (CLSI) on Newborn Screening for Hemoglobinopathies (1). Although deferring to local programs for policies, the report used a cutoff of 25% Hb Bart's in its decision tree, a value many programs do not use. Standardization of screening and reporting might lead to more timely diagnoses and health care services and improved outcomes for persons with a clinically significant alpha-thalassemia.

Bioaccumulation kinetics of cadmium and zinc in the freshwater decapod crustacean Paratya australiensis following multiple pulse exposures.

Stormwater runoff has been identified as a major source of metal contaminants in urban waterways, where during storm events organisms tend to be exposed to short-term pulses, rather than a constant exposure of contaminants. Current water quality guidelines (WQGs) are generally derived using data from continuous exposure toxicity tests, where there is an assumption that chronic exposures provide a meaningful way of assessing the impacts and effects in organisms as a result of these pulsed storm events. In this current study the radioisotopes 109Cd and 65Zn were used to explore uptake, depuration and organ distribution in the decapod crustacean Paratya australiensis, over three short-term (<10 h) exposures. Exposures to radiolabelled cadmium only, zinc only or a mixture of cadmium and zinc were followed by depuration in metal- and isotope-free water for 7 days. Whole-body metal concentrations were determined by live-animal gamma-spectrometry and an anatomical distribution of the radioisotopes was visualised using autoradiography post-mortem. Both metals were significantly accumulated over the pulsed exposure period. In both treatments cadmium and zinc body burden increased at the same rate over the three pulses. Final metal body burden did not markedly differ when shrimp were exposed to metals individually compared to a binary mixture. Over the course of the depuration period, cadmium efflux was minimal, whereas zinc efflux was significant. Autoradiography indicated the presence of both metals in the gills and hepatopancreas throughout the depuration period. These results demonstrate how short-term repeated exposures result in the accumulation of contaminants by shrimp. This study highlights the importance of considering the inclusion of pulsed toxicity tests in frameworks when deriving WQGs.

Metabolomics Provide Sensitive Insights into the Impacts of Low Level Environmental Contamination on Fish Health-A Pilot Study.

This exploratory study aims to investigate the health of sand flathead (Platycephalus bassensis) sampled from five sites in Port Phillip Bay, Australia using gas chromatography-mass spectrometry (GC-MS) metabolomics approaches. Three of the sites were the recipients of industrial, agricultural, and urban run-off and were considered urban sites, while the remaining two sites were remote from contaminant inputs, and hence classed as rural sites. Morphological parameters as well as polar and free fatty acid metabolites were used to investigate inter-site differences in fish health. Significant differences in liver somatic index (LSI) and metabolite abundance were observed between the urban and rural sites. Differences included higher LSI, an increased abundance of amino acids and energy metabolites, and reduced abundance of free fatty acids at the urban sites compared to the rural sites. These differences might be related to the additional energy requirements needed to cope with low-level contaminant exposure through energy demanding processes such as detoxification and antioxidant responses as well as differences in diet between the sites. In this study, we demonstrate that metabolomics approaches can offer a greater level of sensitivity compared to traditional parameters such as physiological parameters or biochemical markers of fish health, most of which showed no or little inter-site differences in the present study. Moreover, the metabolite responses are more informative than traditional biomarkers in terms of biological significance as disturbances in specific metabolic pathways can be identified.

Dietary Uptake and Depuration Kinetics of Perfluorooctane Sulfonate, Perfluorooctanoic Acid, and Hexafluoropropylene Oxide Dimer Acid (GenX) in a Benthic Fish.

Per- and poly-fluoroalkyl substances (PFAS) are ubiquitously distributed throughout aquatic environments and can bioaccumulate in organisms. We examined dietary uptake and depuration of a mixture of 3 PFAS: perfluorooctanoic acid (PFOA; C8 HF15 O2 ), perfluorooctane sulfonate (PFOS; C8 HF17 SO3 ), and hexafluoropropylene oxide dimer acid (HPFO-DA; C6 HF11 O3 ; trade name GenX). Benthic fish (blue spot gobies, Pseudogobius sp.) were fed contaminated food (nominal dose 500 ng g-1 ) daily for a 21-d uptake period, followed by a 42-d depuration period. The compounds PFOA, linear-PFOS (linear PFOS), and total PFOS (sum of linear and branched PFOS) were detected in freeze-dried fish, whereas GenX was not, indicating either a lack of uptake or rapid elimination (<24 h). Depuration rates (d-1 ) were 0.150 (PFOA), 0.045 (linear-PFOS), and 0.042 (linear+branched-PFOS) with corresponding biological half-lives of 5.9, 15, and 16 d, respectively. The PFOS isomers were eliminated differently, resulting in enrichment of linear-PFOS (70-90%) throughout the depuration period. The present study is the first reported study of GenX dietary bioaccumulation potential in fish, and the first dietary study to investigate uptake and depuration of multiple PFASs simultaneously, allowing us to determine that whereas PFOA and PFOS accumulated as expected, GenX, administered in the same way, did not appear to bioaccumulate. Environ Toxicol Chem 2020;39:595-603. © 2019 SETAC.