Partial heart transplant (PHT) is a recent clinical innovation involving the transplantation of a segment of the heart (valves) directly from the deceased donor into the recipient patient. This ...procedure holds out the possibility of significant benefit, especially for pediatric patients because these grafts show growth potential after transplant, reducing or eliminating the current need for repeat procedures. The clinical process for donation and transplant of partial heart (PH) grafts generally follows an organ clinical pathway; however, the Food and Drug Administration has recently stated its intent to regulate PH as tissues, raising a host of regulatory considerations. PHT requires donor testing and eligibility determinations within a short, clinically viable timeframe and, similar to organ transplant, involves donor-recipient matching. Waitlist allocation policies that are a regulatory focus of the Organ Procurement and Transplantation Network including equity and efficiency may become relevant. Oversight of PHT by the Organ Procurement and Transplantation Network could be accomplished through interpretation of the vascular composite allograft definition or through designation by the US Department of Health and Human Services of PH grafts as organs. While some clinical questions remain unanswered, it is important to carefully address these regulatory considerations to support the emergence of this innovation and ensure the continued trust of the donating public and the patients who may benefit from PHT.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Infectious disease transmission through organ and tissue transplantation has been associated with severe complications in recipients. Determination of donor-derived infectious risk associated with ...organ and tissue transplantation is challenging and limited by availability and performance characteristics of current donor epidemiologic screening (e.g., questionnaire) and laboratory testing tools. Common methods and standards for evaluating potential donors of organs and tissues are needed to facilitate effective data collection for assessing the risk for infectious disease transmission. Research programs can use advanced microbiological technologies to define infectious risks posed by pathogens that are known to be transplant transmissible and provide insights into transmission potential of emerging infectious diseases for which transmission characteristics are unknown. Key research needs are explored. Stakeholder collaboration for surveillance and research infrastructure is required to enhance transplant safety.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Organ procurement organizations (OPO) test potential deceased organ donors for infectious diseases required by policy, but many also perform testing for additional infections. The current state of ...donor testing in the United States is unknown. We sent an IRB approved survey to all 57 U.S. OPOs using REDCap. Descriptive statistics were performed. From the 57 OPOs, we received 46 (80.7%) unique responses with all 11 United Network of Organ Sharing regions represented. Forty of 46 (87%) OPO respondents consulted an Infectious Diseases physician when needed. Eighteen of 46 (39%) tested for West Nile virus (WNV) and 17 of 18 (94%) tested year‐round. Eleven of 46 (23.9%) tested for Strongyloides infection while 17 of 46 (37%) tested for Chagas disease. All OPOs performed prospective nucleic acid testing (NAT) for HIV, hepatitis B and hepatitis C on all donors. OPO testing of additional infections has increased since prior surveys but remains variable. Standardization of organ donor infectious diseases evaluation should be considered.
Responses from organ procurement organizations to a survey on testing of all deceased organ donors for infectious diseases shows that less than 40% tested for West Nile virus and Chagas disease, 24% tested for Strongyloides infection, while 100% tested for HIV, hepatitis B, and hepatitis C.
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BFBNIB, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
During 2018, a seabird mortality event occurred in central California, US, that affected Northern Fulmars (Fulmarus glacialis), Common Murres (Uria aalge), and Cassin's Auklets (Ptychoramphus ...aleuticus). An increase in beachcast birds were reported on standardized surveys in conjunction with an increased number of live-stranded birds admitted to rehabilitation centers. Neurologic symptoms were noted during intake examination for some birds. Coincident with the mortality event, increased levels of the harmful algal bloom toxins domoic acid and saxitoxin were recorded in Monterey Bay and Morro Bay. Birds that died in care and beachcast carcasses were submitted to the California Department of Fish and Wildlife–Marine Wildlife Veterinary Care and Research Center for postmortem examination (n=24). All examined birds were emaciated. Examined Common Murres and Cassin's Auklets had no gross evidence of preexisting disease; however, all examined Northern Fulmars exhibited severe pyogranulomatous inflammation of the urogenital system at gross postmortem exam. Tissues from nine Northern Fulmars were examined by histopathology, and samples from two Northern Fulmars were tested for the presence of domoic acid and saxitoxin. Histopathology revealed moderate to severe kidney infection by Eimeria sp. and gram-negative bacteria, intratubular urate stasis, ureter rupture, and emaciation. Additionally, domoic acid and saxitoxin were detected simultaneously in tissues of some tested birds. This communication highlights a novel pattern of cascading comorbidities in native seabirds from a mass stranding event.
Risk for transmission of SARS-CoV-2 through allogeneic human tissue transplantation is unknown. To further evaluate the risk of virus transmission, tissues were obtained from deceased donors who had ...tested positive for SARS-CoV-2 RNA via nasopharyngeal swab. This study evaluated an array of human tissues recovered for transplantation, including bone, tendon, skin, fascia lata, vascular tissues, and heart valves. Tissue samples and plasma or serum samples, if available, were tested for viral RNA (vRNA) using a real time PCR system for the presence of virus RNA. All samples were tested in quadruplicate for both subgenomic (sgRNA) and genomic (gRNA) RNA encoding the SARS-CoV-2 nucleocapsid gene. Amplification of a cellular housekeeping gene served as the positive control for every sample. A total of 47 tissue samples from 17 donors were tested for SARS-CoV-2 RNA. Four donors had plasma or serum available for paired testing. SARS-CoV-2 RNA was not detected from any tissue or plasma/serum sample tested. Based on these findings, risk of transmission through the transplantation of tissue types studied from SARS-CoV-2 infected donors is likely to be low.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract After two multistate outbreaks of allograft tissue‐transmitted tuberculosis (TB) due to viable bone, evidence‐based donor screening criteria were developed to decrease the risk of ...transmission to recipients. Exclusionary criteria, commentary, and references supporting the criteria are provided, based on literature search and expert opinion. Both exposure and reactivation risk factors were considered, either for absolute exclusion or for exclusion in combination with multiple risk factors. A criteria subset was devised for tissues containing viable cells. Risk factors for consideration included exposure (e.g., geographic birth and residence, travel, homelessness, incarceration, healthcare, and workplace) and reactivation (e.g., kidney disease, liver disease, history of transplantation, immunosuppressive medications, and age). Additional donor considerations include the possibility of sepsis and chronic illness. Donor screening criteria represent minimal criteria for exclusion and do not completely exclude all possible donor TB risks. Additional measures to reduce transmission risk, such as donor and product testing, are discussed but not included in the recommendations. Careful donor evaluation is critical to tissue safety.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Contemporary science is a field that is becoming increasingly computational. Today’s scientists not only leverage computational tools to conduct their investigations, they often must contribute to ...the design of the computational tools for their specific research. From a science education perspective, for students to learn authentic science practices, students must learn to use the tools of the trade. This necessity in science education has shaped recent K–12 science standards including the Next Generation Science Standards, which explicitly mention the use of computational tools and simulations. These standards, in particular, have gone further and mandated that
computational thinking
be taught and leveraged as a practice of science. While computational thinking is not a new term, its inclusion in K–12 science standards has led to confusion about what the term means in the context of science learning and to questions about how to differentiate computational thinking from other commonly taught cognitive skills in science like problem-solving, mathematical reasoning, and critical thinking. In this paper, we propose a definition of
computational thinking for science
(CT-S) and a framework for its operationalization in K–12 science education. We situate our definition and framework in Activity Theory, from the learning sciences, in order to position computational thinking as an input to and outcome of science learning that is mediated by computational tools.
Given the possibility for disease transmission, this study was performed to determine whether there is detectable SARS-CoV-2 viral RNA in the blood of deceased tissue donors. A retrospective analysis ...of blood samples from eligible deceased tissue donors from Oct 2019 through June 2020 was performed. Plasma aliquots were initially tested with a SARS-CoV-2 NAT Assay; positive samples were further tested using an alternate NAT and an antibody assay. The proportion of donors with confirmed RNAemia and 95% confidence intervals were computed. Of donor samples collected in 2019, 894 yielded valid results, with 6 initially positive, none of which confirmed positive by alternate NAT. Of donor samples collected in 2020, 2562 yielded valid initial NAT results, with 21 (0.8%) initially positive. Among those, 3 were confirmed by alternate NAT, 17 were not confirmed, and 1 had an invalid alternate NAT result. The rate of SARS-CoV-2 RNAemia in deceased tissue donors is approximately 1 per 1000, and it is unknown whether this RNAemia reflects the presence of infectious virus. Given these results, the risk of transmission through tissue is thought likely to be low.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Background
Evaluation of assay performance on postmortem blood specimens (obtained after cessation of the heartbeat) presents unique scientific and regulatory challenges. In the United States, assay ...performance is evaluated in part by spiking postmortem specimens.
Methods
Fifty‐four specimens obtained from decedents known to be infected with human immunodeficiency virus (HIV), hepatitis C virus (HCV), or hepatitis B virus (HBV), including some coinfections, were tested for each virus using Food and Drug Administration (FDA)‐licensed donor screening tests for nucleic acid, antibody, and antigen.
Results
For each disease, >95% of subjects who were reported to have an infection at the time of death had a positive test result on at least one of the donor screening assays for that infection.
Conclusion
Licensed donor screening tests were positive on postmortem specimens obtained within 24 hours of death from individuals dying with HIV, HCV, and/or HBV, and were able to detect presence of the virus. The use of multiple tests (including antibody and direct viral detection methods) is necessary to adequately evaluate donors.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The marine biotoxin domoic acid (DA) is an analog of the neurotransmitter glutamate that exerts potent excitatory activity in the brain, heart, and other tissues. Produced by the diatom
...Pseudo-nitzschia
spp., DA accumulates in marine invertebrates, fish, and sediment. Southern sea otters (
Enhydra lutris nereis
) feed primarily on invertebrates, including crabs and bivalves, that concentrate and slowly depurate DA. Due to their high prey consumption (25% of body weight/day), sea otters are commonly exposed to DA. A total of 823 necropsied southern sea otters were examined to complete this study; first we assessed 560 subadult, adult, and aged adult southern sea otters sampled from 1998 through 2012 for DA-associated pathology, focusing mainly on the central nervous system (CNS) and cardiovascular system. We applied what was learned to an additional cohort of necropsied sea otters of all demographics (including fetuses, pups, juveniles, and otters examined after 2012:
n
= 263 additional animals). Key findings derived from our initial efforts were consistently observed in this more demographically diverse cohort. Finally, we assessed the chronicity of DA-associated pathology in the CNS and heart independently for 54 adult and aged adult sea otters. Our goals were to compare the temporal consistency of DA-associated CNS and cardiovascular lesions and determine whether multiple episodes of DA toxicosis could be detected on histopathology. Sea otters with acute, fatal DA toxicosis typically presented with neurological signs and severe, diffuse congestion and multifocal microscopic hemorrhages (microhemorrhages) in the brain, spinal cord, cardiovascular system, and eyes. The congestion and microhemorrhages were associated with detection of high concentrations of DA in postmortem urine or gastrointestinal content and preceded histological detection of cellular necrosis or apoptosis. Cases of chronic DA toxicosis often presented with cardiovascular pathology that was more severe than the CNS pathology; however, the lesions at both sites were relatively quiescent, reflecting previous damage. Sea otters with fatal subacute DA toxicosis exhibited concurrent CNS and cardiovascular pathology that was characterized by progressive lesion expansion and host response to DA-associated tissue damage. Acute, subacute, and chronic cases had the same lesion distribution in the CNS and heart. CNS pathology was common in the hippocampus, olfactory, entorhinal and parahippocampal cortex, periventricular neuropil, and ventricles. The circumventricular organs were identified as important DA targets; microscopic examination of the pituitary gland, area postrema, other circumventricular organs, and both eyes facilitated confirmation of acute DA toxicosis in sea otters. DA-associated histopathology was also common in cardiomyocytes and coronary arterioles, especially in the left ventricular free wall, papillary muscles, cardiac apex, and atrial free walls. Progressive cardiomyocyte loss and arteriosclerosis occurred in the same areas, suggesting a common underlying mechanism. The temporal stage of DA-associated CNS pathology matched the DA-associated cardiac pathology in 87% (
n
= 47/54) of cases assessed for chronicity, suggesting that the same underlying process (e.g., DA toxicosis) was the cause of these lesions. This temporally matched pattern is also indicative of a single episode of DA toxicosis. The other 13% of examined otters (
n
= 7/54) exhibited overlapping acute, subacute, or chronic DA pathology in the CNS and heart, suggestive of recurrent DA toxicosis. This is the first rigorous case definition to facilitate diagnosis of DA toxicosis in sea otters. Diagnosing this common but often occult condition is important for improving clinical care and assessing population-level impacts of DA exposure in this federally listed threatened subspecies. Because the most likely source of toxin is through prey consumption, and because humans, sea otters, and other animals consume the same marine foods, our efforts to characterize health effects of DA exposure in southern sea otters can provide strong collateral benefits.
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