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The use of formal privacy to protect the confidentiality of responses in the 2020 Decennial Census of Population and Housing has triggered renewed interest and debate over how to measure the disclosure risks and societal benefits of the published data products. We argue that any proposal for quantifying disclosure risk should be based on prespecified, objective criteria. We illustrate this approach to evaluate the absolute disclosure risk framework, the counterfactual framework underlying differential privacy, and prior-to-posterior comparisons. We conclude that satisfying all the desiderata is impossible, but counterfactual comparisons satisfy the most while absolute disclosure risk satisfies the fewest. Furthermore, we explain that many of the criticisms levied against differential privacy would be levied against any technology that is not equivalent to direct, unrestricted access to confidential data. More research is needed, but in the near term, the counterfactual approach appears best-suited for privacy versus utility analysis.
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Confidencialidade , Revelação , Privacidade , Medição de Risco , CensosRESUMO
BACKGROUND AIMS: Hu8F4 is a T-cell receptor-like antibody with high affinity for the leukemia-associated antigen PR1/HLA-A2 epitope. Adapted into a chimeric antigen receptor (CAR) format, Hu8F4-CAR is composed of the Hu8F4 single-chain variable fragment, the human IgG1 CH2CH3 extracellular spacer domain, a human CD28 costimulatory domain and the human CD3ζ signaling domain. We have demonstrated high efficacy of Hu8F4-CAR-T cells against PR1/HLA-A2-expressing cell lines and leukemic blasts from patients with acute myeloid leukemia in vitro. Previous studies have shown that modification of the Fc domains of IgG4 CH2CH3 spacer regions can eliminate activation-induced cell death and off-target killing mediated by mouse Fc gamma receptor-expressing cells. METHODS: We generated Hu8F4-CAR(PQ) with mutated Fc receptor binding sites on the CH2 domain of Hu8F4-CAR to prevent unwanted interactions with Fc gamma receptor-expressing cells in vivo. RESULTS: The primary human T cells transduced with Hu8F4-CAR(PQ) can specifically lyse HLA-A2+ PR1-expressing leukemia cell lines in vitro. Furthermore, both adult donor-derived and cord blood-derived Hu8F4-CAR(PQ)-T cells are active and can eliminate U937 leukemia cells in NSG mice. CONCLUSIONS: Herein, we demonstrate that modification of the IgG1-based spacer can eliminate Fc receptor binding-induced adverse effects and Hu8F4-CAR(PQ)-T cells can kill leukemia in vivo.
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Arterial calcification due to deficiency of CD73 (ACDC) is a rare genetic disease caused by a loss-of-function mutation in the NT5E gene encoding the ecto-5'-nucleotidase (cluster of differentiation 73, CD73) enzyme. Patients with ACDC develop vessel arteriomegaly, tortuosity, and vascular calcification in their lower extremity arteries. Histological analysis shows that patients with ACDC vessels exhibit fragmented elastin fibers similar to that seen in aneurysmal-like pathologies. It is known that alterations in transforming growth factor ß (TGFß) pathway signaling contribute to this elastin phenotype in several connective tissue diseases, as TGFß regulates extracellular matrix (ECM) remodeling. Our study investigates whether CD73-derived adenosine modifies TGFß signaling in vascular smooth muscle cells (SMCs). We show that Nt5e-/- SMCs have elevated contractile markers and elastin gene expression compared with Nt5e+/+ SMCs. Ecto-5'-nucleotidase (Nt5e)-deficient SMCs exhibit increased TGFß-2 and activation of small mothers against decapentaplegic (SMAD) signaling, elevated elastin transcript and protein, and potentiate SMC contraction. These effects were diminished when the A2b adenosine receptor was activated. Our results identify a novel link between adenosine and TGFß signaling, where adenosine signaling via the A2b adenosine receptor attenuates TGFß signaling to regulate SMC homeostasis. We discuss how disruption in adenosine signaling is implicated in ACDC vessel tortuosity and could potentially contribute to other aneurysmal pathogenesis.
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5'-Nucleotidase , Adenosina , Adenosina/metabolismo , Elastina/genética , Transdução de Sinais , Fator de Crescimento Transformador betaRESUMO
Virus infection is sensed in the cytoplasm by retinoic acid-inducible gene I (RIG-I, also known as DDX58), which requires RNA and polyubiquitin binding to induce type I interferon (IFN) and activate cellular innate immunity. We show that the human IFN-inducible oligoadenylate synthetases-like (OASL) protein has antiviral activity and mediates RIG-I activation by mimicking polyubiquitin. Loss of OASL expression reduced RIG-I signaling and enhanced virus replication in human cells. Conversely, OASL expression suppressed replication of a number of viruses in a RIG-I-dependent manner and enhanced RIG-I-mediated IFN induction. OASL interacted and colocalized with RIG-I, and through its C-terminal ubiquitin-like domain specifically enhanced RIG-I signaling. Bone-marrow-derived macrophages from mice deficient for Oasl2 showed that among the two mouse orthologs of human OASL, Oasl2 is functionally similar to human OASL. Our findings show a mechanism by which human OASL contributes to host antiviral responses by enhancing RIG-I activation.
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2',5'-Oligoadenilato Sintetase/imunologia , RNA Helicases DEAD-box/imunologia , Infecções por Vírus de DNA/imunologia , Interferon Tipo I/imunologia , Infecções por Vírus de RNA/imunologia , 2',5'-Oligoadenilato Sintetase/genética , Animais , Proteína DEAD-box 58 , Células HCT116 , Células HEK293 , Humanos , Imunidade Inata , Fator Regulador 7 de Interferon/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Poliubiquitina , Ligação Proteica/imunologia , Interferência de RNA , RNA Interferente Pequeno , Receptores Imunológicos , Transdução de Sinais/imunologia , Replicação Viral/imunologiaRESUMO
The lack of organs available for transplantation is a global problem. The high mortality rates on the waiting list and the high number of discarded livers are reasons to develop new tools in the preservation and transplantation process. New tools should also be available for low-income countries. This article reports the development of customized normothermic machine perfusion (NMP). An ex vivo dual perfusion machine was designed, composed of a common reservoir organ box (CRO), a centrifugal pump (portal system, low pressure), and a roller pump (arterial system, high pressure). Porcine livers (n = 5) were perfused with an oxygenated normothermic (37â) strategy for 3 hours. Hemodynamic variables, metabolic parameters, and bile production during preservation were analyzed. Arterial and portal flow remain stable during perfusion. Total bilirubin production was 11.25 mL (4-14.5) at 180 minutes. The median pH value reached 7.32 (7.25-7.4) at 180 minutes. Lactate values decreased progressively to normalization at 120 minutes. This perfusion setup was stable and able to maintain the metabolic activity of a liver graft in a porcine animal model. Design and initial results from this customized NMP are promising for a future clinical application in low-income countries.
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Fígado/metabolismo , Preservação de Órgãos/métodos , Perfusão/instrumentação , Animais , Desenho de Equipamento , Feminino , Hemodinâmica , Fígado/irrigação sanguínea , Transplante de Fígado , SuínosRESUMO
PURPOSE: The goals are to gauge caregivers' knowledge of at-home asthma triggers and identify the areas on which educational campaigns can focus to alleviate a child's asthma symptoms. DESIGN AND METHODS: Families with children with moderate to severe asthmatic symptoms who had been recently hospitalized or in the emergency room were invited to participate in a home visit program. As part of the home visit, caregivers of the asthmatic children were asked a series of questions on asthma triggers and the measures for eliminating the triggers (N = 218). RESULTS: Findings show a gap between caregivers' perception of asthma triggers and the actions to mitigate or avoid such triggers. CONCLUSIONS: Overall findings show that home environments were suboptimal for the management and control of child asthma conditions. Knowledge about home triggers as well as the actions and efforts by caregivers and landlords to mitigate these was found to be inadequate. Even when caregivers are aware of the presence of at-home triggers, actions to minimize exposure to the trigger do not always follow due to a lack of power, resource, and knowledge. PRACTICE IMPLICATIONS: The findings raise the need for additional research to investigate the reasons for the lack of actions, advocacy for low-income families to live in a healthy environment, continued education and empowerment, and patient/caregiver-doctor partnership. Additionally, the provision of community support through community advocacy and training of culturally competent healthcare providers are needed for the successful management of pediatric asthma among African American children.
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Asma , Cuidadores , Criança , Humanos , Cuidadores/educação , Negro ou Afro-Americano , Visita Domiciliar , Asma/terapia , PercepçãoAssuntos
Calcificação Vascular , Calcificação Vascular/metabolismo , Animais , Humanos , CamundongosRESUMO
OBJECTIVE: The recessive disease arterial calcification due to deficiency of CD73 (ACDC) presents with extensive nonatherosclerotic medial layer calcification in lower extremity arteries. Lack of CD73 induces a concomitant increase in TNAP (tissue nonspecific alkaline phosphatase; ALPL), a key enzyme in ectopic mineralization. Our aim was to investigate how loss of CD73 activity leads to increased ALPL expression and calcification in CD73-deficient patients and assess whether this mechanism may apply to peripheral artery disease calcification. Approach and Results: We previously developed a patient-specific disease model using ACDC primary dermal fibroblasts that recapitulates the calcification phenotype in vitro. We found that lack of CD73-mediated adenosine signaling reduced cAMP production and resulted in increased activation of AKT. The AKT/mTOR (mammalian target of rapamycin) axis blocks autophagy and inducing autophagy prevented calcification; however, we did not observe autophagy defects in ACDC cells. In silico analysis identified a putative FOXO1 (forkhead box O1 protein) binding site in the human ALPL promoter. Exogenous AMP induced FOXO1 nuclear localization in ACDC but not in control cells, and this was prevented with a cAMP analogue or activation of A2a/2b adenosine receptors. Inhibiting FOXO1 reduced ALPL expression and TNAP activity and prevented calcification. Mutating the FOXO1 binding site reduced ALPL promoter activation. Importantly, we provide evidence that non-ACDC calcified femoropopliteal arteries exhibit decreased CD73 and increased FOXO1 levels compared with control arteries. CONCLUSIONS: These data show that lack of CD73-mediated cAMP signaling promotes expression of the human ALPL gene via a FOXO1-dependent mechanism. Decreased CD73 and increased FOXO1 was also observed in more common peripheral artery disease calcification.
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5'-Nucleotidase/deficiência , Fibroblastos/enzimologia , Proteína Forkhead Box O1/metabolismo , Doença Arterial Periférica/enzimologia , Artéria Poplítea/enzimologia , Calcificação Vascular/enzimologia , 5'-Nucleotidase/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Autofagia , Estudos de Casos e Controles , Células Cultivadas , Feminino , Fibroblastos/patologia , Proteína Forkhead Box O1/genética , Proteínas Ligadas por GPI/deficiência , Proteínas Ligadas por GPI/genética , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/genética , Doença Arterial Periférica/patologia , Artéria Poplítea/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Calcificação Vascular/genética , Calcificação Vascular/patologia , Adulto JovemRESUMO
ABSTRACT: Mycobacterium infection remains a leading cause of morbidity and mortality worldwide. Although rare, thoracic cardiovascular complications are associated with devastating consequences if not promptly diagnosed using computed tomography. Intrapulmonary complications include tuberculous aortitis, Rasmussen aneurysms, involvement of bronchial and nonbronchial systemic arteries, and thromboembolic events. Extrapulmonary complications include pericarditis, myocarditis, endocarditis, involvement of coronary arteries, annular-subvalvular left ventricle aneurysms and mediastinal fibrosis. This article will review these complications and their computed tomography features.
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Doenças Cardiovasculares/diagnóstico por imagem , Tuberculose Pulmonar/complicações , Doença da Artéria Coronariana/diagnóstico por imagem , Endocardite/diagnóstico por imagem , Aneurisma Cardíaco/diagnóstico por imagem , Humanos , Mediastinite/diagnóstico por imagem , Pericardite/diagnóstico por imagem , Esclerose/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Tuberculose Pulmonar/diagnóstico por imagemRESUMO
Psychiatric drugs are among the leading medications prescribed for humans, with their presence in aquatic environments raising concerns relating to potentially harmful effects on non-target organisms. Nortriptyline (NTP) is a selective serotonin-norepinephrine reuptake inhibitor antidepressant, widely used in clinics and found in environmental water matrices. In this study, we evaluated the toxic effects of NTP on zebrafish (Danio rerio) embryos and early larval stages. Developmental and mortality analyses were performed on zebrafish exposed to NTP for 168 h at concentrations ranging from 500 to 46,900 µg/L. Locomotor behaviour and acetylcholinesterase (AChE) activity were evaluated by exposing embryos/larvae to lower NTP concentrations (0.006-500 µg/L). The median lethal NTP concentration after 168 h exposure was 2190 µg/L. Although we did not identify significant developmental changes in the treated groups, lack of equilibrium was already visible in surviving larvae exposed to ≥ 500 µg/L NTP. The behavioural analyses showed that NTP was capable of modifying zebrafish larvae swimming behaviour, even at extremely low (0.006 and 0.088 µg/L) environmentally relevant concentrations. We consistently observed a significant reduction in AChE activity in the animals exposed to 500 µg/L NTP. Our results highlight acute toxic effects of NTP on the early-life stages of zebrafish. Most importantly, exposure to environmentally relevant NTP concentrations may affect zebrafish larvae locomotor behaviour, which in turn could reduce the fitness of the species. More studies involving chronic exposure and sensitive endpoints are warranted to better understand the effect of NTP in a more realistic exposure scenario.
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Inibidores da Captação Adrenérgica/toxicidade , Antidepressivos Tricíclicos/toxicidade , Nortriptilina/toxicidade , Inibidores Seletivos de Recaptação de Serotonina/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Acetilcolinesterase/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Larva/efeitos dos fármacos , Locomoção/efeitos dos fármacosRESUMO
The discovery of efficient organocatalysts is generally carried out by thorough experimental screening of different candidates. We recently reported an efficient organocatalyst for iminium-ion-based asymmetric Diels-Alder reactions following a rational design approach. This result encouraged us to test this optimal catalyst in the mechanistically related Friedel-Crafts alkylation of indoles, but to our surprise, almost null enantioselectivity was observed. The results did not significantly improve with structurally related catalysts, and a totally unexpected facial selectivity inversion was also noticed. Using DFT calculations by modeling the competing transition structures with ONIOM, we could unravel the origins of those findings, further employed to predict the most efficient catalyst for this new transformation. The computational results were validated experimentally (up to 92:8 er), providing another successful example of a general strategy to accelerate catalyst development which still remains underexplored.
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A series of levoglucosenone-derived 1,2,3-triazoles and isoxazoles featuring a flexible spacer between the heteroaromatic and anhydropyranose cores have been designed and synthesized following an hetero Michael // 1,3-dipolar cycloaddition path. The use of a design of experiments approach allowed the optimization of the oxa-Michael reaction with propargyl alcohol as nucleophile, a key step for the synthesis of the target compounds. All of the compounds were tested for their anticancer activity on MDA-MB-231 cells, featuring mutant p53. The results highlighted the importance of the introduction of the flexible spacer as well as the higher activity of oxa-Michael isoxazole-derivatives. The most prominent compounds also showed anti-proliferative activities against lung and colon cancer cell lines. The compounds showed enhanced cytotoxic effects in the presence of mutant p53, determined both by endogenous mutant p53 knock down (R280K) and by reintroducing p53 R280K in cells lacking p53 expression.
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Antineoplásicos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Desenho de Fármacos , Glucose/análogos & derivados , Isoxazóis/farmacologia , Triazóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Glucose/síntese química , Glucose/química , Glucose/farmacologia , Humanos , Isoxazóis/química , Estrutura Molecular , Relação Estrutura-Atividade , Triazóis/químicaRESUMO
The Republic of Panama has the second most unequally distributed wealth in Central America, has recently entered the list of countries affected by the COVID-19 pandemic, and has one of the largest testing rate per inhabitant in the region and consequently the highest incidence rate of COVID-19, making it an ideal location to discuss potential scenarios for assessing epidemic preparedness, and to outline research opportunities in the Region of the Americas. We address two timely important questions: What are the unique risks of COVID-19 in Panama that could help other countries in the Region be better prepared? And what kind of scientific knowledge can Panama contribute to the regional and global study of COVID-19? This paper provides suggestions about how the research community could support local health authorities plan for different scenarios and decrease public anxiety. It also presents basic scientific opportunities about emerging pandemic pathogens towards promoting global health from the perspective of a middle income country.
La República de Panamá es el segundo país de Centroamérica con la distribución más desigual de la riqueza, ha resultado afectado recientemente por la pandemia de COVID-19 y tiene una de las mayores tasas de pruebas diagnósticas por habitante de la región y, por consiguiente, la mayor tasa de incidencia de COVID-19. Estos aspectos la convierten en un lugar ideal para examinar posibles escenarios de evaluación de la preparación para la epidemia y para plantear oportunidades de investigación en la Región de las Américas. Se abordan dos preguntas importantes y oportunas: ¿Cuáles son los riesgos singulares de la COVID-19 en Panamá que podrían ayudar a otros países de la Región a estar mejor preparados? y ¿Qué tipo de conocimiento científico puede aportar Panamá al estudio regional y mundial de la COVID-19? En este artículo se presentan sugerencias sobre la forma en que la comunidad de investigadores podría apoyar a las autoridades sanitarias locales a planificar medidas ante diferentes escenarios y disminuir la ansiedad de la población. También se presentan oportunidades científicas básicas sobre patógenos pandémicos emergentes para promover la salud mundial desde la perspectiva de un país de ingresos medios.
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Aterosclerose , Calcinose , Calcificação Vascular , Aterosclerose/genética , Aterosclerose/metabolismo , Calcinose/metabolismo , Epigênese Genética , Humanos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Calcificação Vascular/genética , Calcificação Vascular/metabolismoRESUMO
BACKGROUND: Malaria control in Panama is problematic due to the high diversity of morphologically similar Anopheles mosquito species, which makes identification of vectors of human Plasmodium challenging. Strategies by Panamanian health authorities to bring malaria under control targeting Anopheles vectors could be ineffective if they tackle a misidentified species. METHODS: A rapid mass spectrometry identification procedure was developed to accurately and timely sort out field-collected Neotropical Anopheles mosquitoes into vector and non-vector species. Matrix-assisted laser desorption/ionization (MALDI) mass spectra of highly-abundant proteins were generated from laboratory-reared mosquitoes using different extraction protocols, body parts, and sexes to minimize the amount of material from specimen vouchers needed and optimize the protocol for taxonomic identification. Subsequently, the mass spectra of field-collected Neotropical Anopheles mosquito species were classified using a combination of custom-made unsupervised (i.e., Principal component analysis-PCA) and supervised (i.e., Linear discriminant analysis-LDA) classification algorithms. RESULTS: Regardless of the protocol used or the mosquito species and sex, the legs contained the least intra-specific variability with enough well-preserved proteins to differentiate among distinct biological species, consistent with previous literature. After minimizing the amount of material needed from the voucher, one leg was enough to produce reliable spectra between specimens. Further, both PCA and LDA were able to classify up to 12 mosquito species, from different subgenera and seven geographically spread localities across Panama using mass spectra from one leg pair. LDA demonstrated high discriminatory power and consistency, with validation and cross-validation positive identification rates above 93% at the species level. CONCLUSION: The selected sample processing procedure can be used to identify field-collected Anopheles species, including vectors of Plasmodium, in a short period of time, with a minimal amount of tissue and without the need of an expert mosquito taxonomist. This strategy to analyse protein spectra overcomes the drawbacks of working without a reference library to classify unknown samples. Finally, this MALDI approach can aid ongoing malaria eradication efforts in Panama and other countries with large number of mosquito's species by improving vector surveillance in epidemic-prone sites such as indigenous Comarcas.
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Anopheles/classificação , Mosquitos Vetores/classificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Malária/transmissão , Panamá , Plasmodium/fisiologiaRESUMO
Hospital leaders encourage morning discharge of patients to boost patient flow. This work presents a detailed process of a building model for forecasting patient discharge before noon applying the Box-Jenkins methodology using weekly historic data. Accurately forecasting is of crucial importance to plan early discharge activities, influenced by the fluctuations in daily discharges process. The objective is to find an appropriate autoregressive integrated moving average (ARIMA) model for forecasting the rate of patients out by noon based on the lowest error in a statistical forecast by applying the mean absolute percentage error. The results obtained demonstrate that a nonseasonal ARIMA model classified as ARIMA(2,1,1) offers a good fit to actual discharge-before-noon data and proposes hospital leaders short-term prediction that could facilitate decision-making process, which is important in an uncertain health care system environment.
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Previsões/métodos , Modelos Estatísticos , Alta do Paciente/estatística & dados numéricos , Humanos , Fatores de TempoRESUMO
Streptococcus pneumoniae (pneumococcus) is a major human pathogen. It is a common colonizer of the human respiratory track, where it utilizes cell-cell communication systems to coordinate population-level behaviors. We reasoned that secreted peptides that are highly expressed during infection are pivotal for virulence. Thus, we used in silico pattern searches to define a pneumococcal secretome and analyzed the transcriptome of the clinically important PMEN1 lineage to identify which peptide-encoding genes are highly expressed in vivo. In this study, we characterized virulence peptide 1 (vp1), a highly expressed Gly-Gly peptide-encoding gene in chinchilla middle ear effusions. The vp1 gene is widely distributed across pneumococcus as well as encoded in related species. Studies in the chinchilla model of middle ear infection demonstrated that VP1 is a virulence determinant. The vp1 gene is positively regulated by a transcription factor from the Rgg family and its cognate SHP (short hydrophobic peptide). In vitro data indicated that VP1 promotes increased thickness and biomass for biofilms grown on chinchilla middle ear epithelial cells. Furthermore, the wild-type biofilm is restored with the exogenous addition of synthetic VP1. We conclude that VP1 is a novel streptococcal regulatory peptide that controls biofilm development and pneumococcal pathogenesis.
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Biofilmes/crescimento & desenvolvimento , Streptococcus pneumoniae/metabolismo , Virulência/genética , Animais , Proteínas de Bactérias/metabolismo , Comunicação Celular/fisiologia , Chinchila , Bases de Dados de Ácidos Nucleicos , Orelha Média/microbiologia , Regulação Bacteriana da Expressão Gênica/genética , Otite Média/microbiologia , Peptídeos/metabolismo , Infecções Pneumocócicas/metabolismo , Análise de Sequência de DNA/métodos , Streptococcus/metabolismo , Streptococcus pneumoniae/genética , Fatores de Virulência/genética , Fatores de Virulência/metabolismoRESUMO
Uridine triacetate has been shown to be an effective antidote against mortality and toxicity caused by either overdoses or exaggerated susceptibility to the widely used anticancer agents 5-fluorouracil (5-FU) and capecitabine. However, a direct assessment of efficacy based on when emergency treatment was initiated was not clinically feasible. In this study we used mouse models of 5-FU overdose and of dihydropyrimidine dehydrogenase (DPD) deficiency to compare the efficacy of uridine triacetate in reducing toxicity and mortality when treatment was initiated at time points from 4 to 144â¯h after administration of 5-FU. We found that uridine triacetate was effective both in the 5-FU overdose and DPD deficiency models. Starting treatment within 24â¯h was most effective at reducing toxicity and mortality in both models, while treatment starting more than 96 to 120â¯h after 5-FU was far less effective. Uridine triacetate also reduced mortality in the DPD deficiency model when mice were treated with the 5-FU prodrug capecitabine. The results of this study are supportive of clinical observations and practice, indicating that efficacy declined progressively with later and later treatment initiation. Prompt treatment with uridine triacetate, within 24â¯h, conferred the greatest protection against 5-FU overexposure.