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1.
Regul Toxicol Pharmacol ; 147: 105558, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38145839

RESUMO

New Approach Methodologies (NAMs) are a rapidly growing set of tools/methods for use food, drug, consumer product, or chemical safety assessment paradigms. The massive growth in NAMs tech development, publication, and legislation has been paralleled by a growing sense of frustration. The challenge of realizing the systems-level changes needed to catalyze the broad-scale adoption and use of NAMs is substantial. This Commentary asserts that these challenges may be less unique than perceived to date, and points to specific opportunities to learn from decades of experience (both positive and negative) from the Quality Improvement (QI) movement in the public health and healthcare arenas. Specific recommendations to inform and guide NAMs development are offered.


Assuntos
Melhoria de Qualidade
2.
Regul Toxicol Pharmacol ; : 105668, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38936797

RESUMO

Drug-induced kidney injury (DIKI) refers to kidney damage resulting from the administration of medications. The aim of this project was to identify reliable urinary microRNA (miRNAs) biomarkers that can be used as potential predictors of DIKI before disease diagnosis. This study quantified a panel of six miRNAs (miRs-210-3p, 423-5p, 143-3p, 130b-3p, 486-5p, 193a-3p) across multiple time points using urinary samples from a previous investigation evaluating effects of a nephrotoxicant in cynomolgus monkeys. Exosome-associated miRNA exhibited distinctive trends when compared to miRNAs quantified in whole urine, which may reflect a different urinary excretion mechanism of miRNAs than those released passively into the urine. Although further research and mechanistic studies are required to elucidate how these miRNAs regulate signaling in disease pathways, we present, for the first time, data that several miRNAs displayed strong correlations with histopathology scores, thus indicating their potential use as biomarkers to predict the development of DIKI in preclinical studies and clinical trials. Also, these findings can potentially be translated into other non-clinical species or human for the detection of DIKI.

3.
Regul Toxicol Pharmacol ; 110: 104526, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726190

RESUMO

Robust genomic approaches are now available to realize improvements in efficiencies and translational relevance of cancer risk assessments for drugs and chemicals. Mechanistic and pathway data generated via genomics provide opportunities to advance beyond historical reliance on apical endpoints of uncertain human relevance. Published research and regulatory evaluations include many examples for which genomic data have been applied to address cancer risk assessment as a health protection endpoint. The alignment of mature, robust, reproducible, and affordable technologies with increasing demands for reduced animal testing sets the stage for this important transition. We present our shared vision for change from leading scientists from academic, government, nonprofit, and industrial sectors and chemical and pharmaceutical safety applications. This call to action builds upon a 2017 workshop on "Advances and Roadblocks for Use of Genomics in Cancer Risk Assessment." The authors propose a path for implementation of innovative cancer risk assessment including incorporating genomic signatures to assess mechanistic relevance of carcinogenicity and enhanced use of genomics in benchmark dose and point of departure evaluations. Novel opportunities for the chemical and pharmaceutical sectors to combine expertise, resources, and objectives to achieve a common goal of improved human health protection are identified.


Assuntos
Carcinógenos/toxicidade , Neoplasias/induzido quimicamente , Medição de Risco , Toxicogenética , Animais , Testes de Carcinogenicidade , Indústria Química , Indústria Farmacêutica , Humanos
4.
Cancer ; 125(24): 4471-4480, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31454424

RESUMO

BACKGROUND: With increasing survival rates, a growing population of patients with cancer have received or will receive adjuvant therapy to prevent cancer recurrences. Patients and caregivers will confront the complexities of balancing the preventative benefits of adjuvant therapy with possible near-term or long-term adverse events (AEs). Adjuvant treatment-related AEs (from minimal to severe) can impact therapeutic adherence, quality of life, emotional and physical health, and survival. However, to the authors' knowledge, limited information is available regarding how stakeholders use or desire to use adjuvant-related AE information to inform the care of patients with cancer. METHODS: A qualitative, purposeful sampling approach was used to elicit stakeholder feedback via semistructured interviews (24 interviews). Drug development, drug regulatory, clinical, payer, and patient/patient advocacy stakeholders were questioned about the generation, dissemination, and use of adjuvant treatment-related AE information to inform the care of patients with cancer. Transcripts were coded independently by 2 senior health care researchers and reconciled to identify key themes. RESULTS: All stakeholder groups in the current study identified needed improvements in each of the following 4 areas: 1) improving the accessibility and relevance of AE-related information; 2) better integrating and implementing available information regarding AEs for decisions; 3) connecting contemporary cultural and economic value systems to the generation and use of information regarding adjuvant treatment-related AEs; and 4) addressing a lack of alignment and ownership of stakeholder efforts to improve the use of AE information in the adjuvant setting. CONCLUSIONS: Despite commonalities in the overall needs identified by the diverse stakeholders in the current study, broad systemic change has been stymied. The current study identified the lack of alignment and the absence of a central "owner" of these diffuse efforts as a previously unrecognized hurdle to realizing the desired systemic improvements. Future initiatives aimed at improving quality of life and outcomes for patients receiving adjuvant therapy through the improved use of AE information must address this challenge through innovative collectives and novel leadership strategies.


Assuntos
Quimioterapia Adjuvante/efeitos adversos , Neoplasias/epidemiologia , Cuidadores , Quimioterapia Adjuvante/métodos , Pesquisas sobre Atenção à Saúde , Pessoal de Saúde , Humanos , Neoplasias/terapia , Médicos , Pesquisa Qualitativa
5.
Am Heart J ; 167(3): 292-300, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24576511

RESUMO

This white paper provides a summary of a scientific proposal presented at a Cardiac Safety Research Consortium/Health and Environmental Sciences Institute/Food and Drug Administration-sponsored Think Tank, held at Food and Drug Administration's White Oak facilities, Silver Spring, MD, on July 23, 2013, with the intention of moving toward consensus on defining a new paradigm in the field of cardiac safety in which proarrhythmic risk would be primarily assessed using nonclinical in vitro human models based on solid mechanistic considerations of torsades de pointes proarrhythmia. This new paradigm would shift the emphasis from the present approach that strongly relies on QTc prolongation (a surrogate marker of proarrhythmia) and could obviate the clinical Thorough QT study during later drug development. These discussions represent current thinking and suggestions for furthering our knowledge and understanding of the public health case for adopting a new, integrated nonclinical in vitro/in silico paradigm, the Comprehensive In Vitro Proarrhythmia Assay, for the assessment of a candidate drug's proarrhythmic liability, and for developing a public-private collaborative program to characterize the data content, quality, and approaches required to assess proarrhythmic risk in the absence of a Thorough QT study. This paper seeks to encourage multistakeholder input regarding this initiative and does not represent regulatory guidance.


Assuntos
Arritmias Cardíacas/induzido quimicamente , Avaliação Pré-Clínica de Medicamentos/métodos , Técnicas de Patch-Clamp/métodos , Arritmias Cardíacas/prevenção & controle , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Humanos , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/prevenção & controle , Medição de Risco , Torsades de Pointes/induzido quimicamente , Torsades de Pointes/prevenção & controle , Estados Unidos
6.
Toxicol Pathol ; 42(7): 1092-104, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24670813

RESUMO

Differences were examined between male and female Sprague-Dawley rats in basal levels of a wide range of urinary biomarkers, including 7 recently qualified biomarkers. The data were generated from urine samples collected on 3 occasions from untreated rats included in a study of the effect of gentamicin nephrotoxicity on urinary renal biomarkers, reported in a companion article in this journal (Gautier et al. 2014). The performance of multiple assays (9 singleplex assays and 2 multiplex platforms from Rules Based Medicine [RBM] and Meso Scale Discovery [MSD]) was evaluated, and normal ranges and variability estimates were derived. While variability was generally greater on the RBM platform than other assays, the more striking difference in the results from different assays was in magnitude. Where differences were observed between assays for an individual biomarker, they were seen in both sexes and consistent across samples collected at different time points. Differences of up to 15-fold were observed for some biomarker values between assays indicating that results generated using different assays should not be compared. For 8 biomarkers, there was compelling evidence for a sex difference. Baseline values in males were significantly higher than in females for total protein, ß2-microglobulin, clusterin, cystatin-C, glutathione-S-transferase (GST-α), tissue inhibitor of metalloproteinases (TIMP-1), and vascular endothelial growth factor (VEGF); female values were significantly higher than that of males for albumin. The largest sex differences (male greater than female by 2- to 11-fold) were seen with ß2-microglobulin, GST-α, and TIMP-1. These data add substantially to the limited body of knowledge in this area and provide a useful framework for evaluation of the potential relevance of sex differences in the diagnostic performance of these biomarkers.


Assuntos
Bioensaio/métodos , Biomarcadores/urina , Fatores Sexuais , Animais , Clusterina/genética , Clusterina/metabolismo , Cistatina C/genética , Cistatina C/metabolismo , Feminino , Gentamicinas/administração & dosagem , Gentamicinas/efeitos adversos , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Valores de Referência , Reprodutibilidade dos Testes , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Microglobulina beta-2/genética , Microglobulina beta-2/metabolismo
7.
Toxicol Pathol ; 42(7): 1105-16, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24717899

RESUMO

Differences were examined between male and female Sprague-Dawley rats in the response of 16 urinary biomarkers (measured using several assay platforms) to renal injury produced by gentamicin administered subcutaneously for 10 days at a dosage of 75 mg/kg. Urinary biomarkers expressed as fold difference from contemporaneous controls and renal histopathology were assessed after 3 and 10 doses. On day 4, minimal proximal tubular changes were observed microscopically in all males but no females; on day 11, more extensive and more severe injury was observed to a similar extent in all animals of both sexes. Modest increases (maximum 5-fold) in all urinary biomarkers (except epidermal growth factor [EGF], which was decreased) on day 4 and marked elevations (maximum 271-fold) on day 11 were seen consistently in both sexes. However, the magnitude of the increases differed between the sexes. On day 4, despite the lack of tubular injury, many biomarkers were more elevated in females than males but this rarely led to statistically significant sex differences; only 2 biomarkers (ß2-microglobulin and total protein) showed a greater increase in males than females in line with the histopathology. On day 11, there were many more biomarkers that showed a statistically significant difference between the sexes in fold change with treatment; in line with the results on day 4, the majority of biomarkers were more increased in females than males. It remains unresolved if sex differences in the magnitude of biomarker response at injury threshold would lead to any difference in diagnostic interpretation between the sexes. These data highlight the need for publication of more studies using animals of both sexes to fully explore the influence of sex on the diagnostic performance of the novel biomarkers.


Assuntos
Biomarcadores/urina , Gentamicinas/efeitos adversos , Nefropatias/patologia , Rim/efeitos dos fármacos , Fatores Sexuais , Animais , Relação Dose-Resposta a Droga , Feminino , Gentamicinas/administração & dosagem , Rim/patologia , Nefropatias/induzido quimicamente , Masculino , Ratos , Ratos Sprague-Dawley , Microglobulina beta-2/urina
8.
Front Toxicol ; 6: 1352783, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590785

RESUMO

Traditional approaches to preclinical drug safety assessment have generally protected human patients from unintended adverse effects. However, these assessments typically occur too late to make changes in the formulation or in phase 1 and beyond, are highly dependent on animal studies and have the potential to lead to the termination of useful drugs due to liabilities in animals that are not applicable in patients. Collectively, these elements come at great detriment to both patients and the drug development sector. This phenomenon is particularly problematic in the area of cardiovascular safety assessment where preclinical attrition is high. We believe that a more efficient and translational approach can be defined. A multi-tiered assessment that leverages our understanding of human cardiovascular biology, applies human cell-based in vitro characterizations of cardiovascular responses to insult, and incorporates computational models of pharmacokinetic relationships would enable earlier and more translational identification of human-relevant liabilities. While this will take time to develop, the ultimate goal would be to implement such assays both in the lead selection phase as well as through regulatory phases.

9.
Toxicol Pathol ; 41(8): 1146-58, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23531791

RESUMO

Cardiac troponin (cTn) has been utilized to assess acute myocardial injury, but the cTn response in active/ongoing chronic injury is not well documented. The purpose of this study was to characterize the cardiac troponin I (cTnI), cardiac troponin T (cTnT), high-sensitivity cTnI, hematology, and clinical chemistry responses in rats treated with doxorubicin. Rats treated with 1, 2, or 3 mg/kg/week (wk) of doxorubicin for 2, 4, or 6 wks were sacrificed after 0, 2, or 4 wks of recovery and compared to untreated controls and animals treated with doxorubicin/dexrazoxane (50 mg/kg/wk) or etoposide (1 and 3 mg/kg/wk). The incidence and mean magnitude of cTn response increased with increasing dose and/or duration of doxorubicin treatment. Conversely, dexrazoxane/doxorubicin was partially protective for cardiotoxicity, and minimal cardiotoxicity occurred with etoposide treatment. Both cTnI and cTnT effectively identified doxorubicin-induced injury as indicated by vacuolation of cardiomyocytes of the atria/ventricles. The association between the cTn responses and histological changes was greater at the higher total exposures, but the magnitude of cTn response did not match closely with histologic grade. The high-sensitivity cTnI assay was also effective in identifying cardiac injury. Alterations occurred in the hematology and clinical chemistry parameters and reflected both dose and duration of doxorubicin treatment.


Assuntos
Doxorrubicina/toxicidade , Cardiopatias/sangue , Cardiopatias/induzido quimicamente , Troponina I/sangue , Troponina T/sangue , Animais , Peso Corporal/efeitos dos fármacos , Testes de Química Clínica , Ingestão de Alimentos/efeitos dos fármacos , Coração/efeitos dos fármacos , Cardiopatias/metabolismo , Testes Hematológicos , Masculino , Miocárdio/química , Ratos , Ratos Sprague-Dawley , Sensibilidade e Especificidade , Testes de Toxicidade
10.
Toxicol Pathol ; 41(3): 445-53, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22991386

RESUMO

The Health and Environmental Sciences Institute Cardiac Biomarkers Working Group surveyed the pharmaceutical development community to investigate practices in assessing hemostasis, including detection of hypocoagulable and hypercoagulable states. Scientists involved in discovery, preclinical, and clinical research were queried on laboratory evaluation of endothelium, platelets, coagulation, and fibrinolysis during safety assessment studies. Results indicated that laboratory assessment of hemostasis is inconsistent among institutions and not harmonized between preclinical and clinical studies. Hemostasis testing in preclinical drug safety studies primarily focuses on the risk of bleeding, whereas the clinical complication of thrombosis is seldom assessed. Our results reveal the need for broader utilization of biomarkers to detect altered hemostasis (e.g., endothelial and platelet activation) to improve preclinical safety assessments early in the drug development process. Survey respondents indicated a critical lack of validated markers of hypercoagulability and subclinical thrombosis in animal testing. Additional obstacles included limited blood volume, lack of cross-reacting antibodies for hemostasis testing in laboratory species, restricted availability of specialized hemostasis analyzers, and few centers of expertise in animal hemostasis testing. Establishment of translatable biomarkers of prothrombotic states in multiple species and strategic implementation of testing on an industry-wide basis are needed to better avert untoward drug complications in patient populations.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/normas , Indústria Farmacêutica/organização & administração , Hemostasia/efeitos dos fármacos , Tromboembolia/induzido quimicamente , Animais , Pesquisa Biomédica , Testes de Coagulação Sanguínea , Hemostasia/fisiologia , Humanos , Projetos de Pesquisa , Medição de Risco/métodos , Medição de Risco/normas , Inquéritos e Questionários , Tromboembolia/sangue , Tromboembolia/diagnóstico
11.
Regul Toxicol Pharmacol ; 65(1): 38-46, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23044254

RESUMO

Cardiovascular (CV) safety concerns are a significant source of drug development attrition in the pharmaceutical industry today. Though current nonclinical testing paradigms have largely prevented catastrophic CV events in Phase I studies, many challenges relating to the inability of current nonclinical safety testing strategies to model patient outcomes persist. Contemporary approaches include a spectrum of evaluations of CV structure and function in a variety of laboratory animal species. These approaches might be improved with a more holistic integration of these evaluations in repeat-dose studies, addition of novel endpoints with greater sensitivity and translational application, and use of more relevant animal models. Particular opportunities present with advances in imaging capabilities applicable to rodent and non-rodent species, technical capabilities for measuring CV function in repeat-dose animal studies, detection and quantitation of microRNAs and wider use of alternative animal models. Strategic application of these novel opportunities considering putative CV risk associated with the molecular drug target as well as inherent risks present in the target patient population could tailor or 'personalize' nonclinical safety assessment as a more translational evaluation. This paper is a call to action for the clinical and nonclinical drug safety communities to assess these opportunities to determine their utility in filling potential gaps in our current cardiovascular safety testing paradigms.


Assuntos
Doenças Cardiovasculares/induzido quimicamente , Desenho de Fármacos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Animais , Modelos Animais de Doenças , Indústria Farmacêutica/métodos , Determinação de Ponto Final , Humanos , MicroRNAs/metabolismo , Projetos de Pesquisa , Medição de Risco/métodos , Especificidade da Espécie
12.
Front Pharmacol ; 14: 1210579, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37502215

RESUMO

The COVID-19 pandemic sparked the development of novel anti-viral drugs that have shown to be effective in reducing both fatality and hospitalization rates in patients with elevated risk for COVID-19 related morbidity or mortality. Currently, nirmatrelvir/ritonavir (Paxlovid™) fixed-dose combination is recommended by the World Health Organization for treatment of COVID-19. The ritonavir component is an inhibitor of cytochrome P450 (CYP) 3A, which is used in this combination to achieve needed therapeutic concentrations of nirmatrelvir. Because of the critical pharmacokinetic effect of this mechanism of action for Paxlovid™, co-administration with needed medications that inhibit or induce CYP3A is contraindicated, reflecting concern for interactions with the potential to alter the efficacy or safety of co-administered drugs that are also metabolized by CYP3A. Some herbal medicines are known to interact with drug metabolizing enzymes and transporters, including but not limited to inhibition or induction of CYP3A and P-glycoprotein. As access to these COVID-19 medications has increased in low- and middle-income countries (LMICs), understanding the potential for herb-drug interactions within these regions is important. Many studies have evaluated the utility of herbal medicines for COVID-19 treatments, yet information on potential herb-drug interactions involving Paxlovid™, specifically with herbal medicines commonly used in LMICs, is lacking. This review presents data on regionally-relevant herbal medicine use (particularly those promoted as treatments for COVID-19) and mechanism of action data on herbal medicines to highlight the potential for herbal medicine interaction Herb-drug interaction mediated by ritonavir-boosted antiviral protease inhibitors This work highlights potential areas for future experimental studies and data collection, identifies herbal medicines for inclusion in future listings of regionally diverse potential HDIs and underscores areas for LMIC-focused provider-patient communication. This overview is presented to support governments and health protection entities as they prepare for an increase of availability and use of Paxlovid™.

13.
Toxicol Pathol ; 40(4): 682-94, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22301952

RESUMO

N-phenylanthranilic acid is a chloride channel blocker that causes renal papillary necrosis in rats. Studies were conducted in two strains of male rats to evaluate novel biomarkers of nephrotoxicity. Han-Wistar rats were given daily oral doses of 50, 350, or up to 700 mg/kg/day of NPAA, and Sprague-Dawley rats were given 50 or 400 mg/kg/day of NPAA. Rats were euthanized on days 8 and 15. The candidate kidney injury biomarkers renal papillary antigen-1 (RPA-1, for collecting duct injury), clusterin (for general kidney injury), α-glutathione-S-transferase (a proximal tubular marker), and µ-glutathione-S-transferase (a distal tubular marker) were measured in urine by enzyme immunoassay. Characteristic degeneration and necrosis of the collecting duct and renal papilla were observed in Han-Wistar rats at the high dose on day 8 and at the mid and high doses on day 15, and in Sprague-Dawley rats given the high dose on days 8 and 15. Increases in urinary RPA-1, and to a lesser extent urine clusterin, were generally associated with the presence of collecting duct injury and were more sensitive than BUN and serum creatinine. On the other hand, decreases in α-glutathione-S-transferase without proximal tubule lesions in both strains and decreases in µ-glutathione-S-transferase in Sprague-Dawley rats only were not associated with morphological proximal or distal tubule abnormalities, so both were of less utility. It was concluded that RPA-1 is a new biomarker with utility in the detection of collecting duct injury in papillary necrosis in male rats.


Assuntos
Nefropatias/induzido quimicamente , Túbulos Renais Coletores/efeitos dos fármacos , ortoaminobenzoatos/toxicidade , Análise de Variância , Animais , Biomarcadores/análise , Biomarcadores/sangue , Biomarcadores/urina , Nitrogênio da Ureia Sanguínea , Clusterina/urina , Creatinina/sangue , Glutationa Transferase/urina , Histocitoquímica , Nefropatias/sangue , Nefropatias/patologia , Nefropatias/urina , Túbulos Renais Coletores/patologia , Masculino , Necrose , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Testes de Toxicidade
14.
Front Toxicol ; 4: 991590, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36211197

RESUMO

Genotoxicity testing relies on the detection of gene mutations and chromosome damage and has been used in the genetic safety assessment of drugs and chemicals for decades. However, the results of standard genotoxicity tests are often difficult to interpret due to lack of mode of action information. The TGx-DDI transcriptomic biomarker provides mechanistic information on the DNA damage-inducing (DDI) capability of chemicals to aid in the interpretation of positive in vitro genotoxicity data. The CometChip® assay was developed to assess DNA strand breaks in a higher-throughput format. We paired the TGx-DDI biomarker with the CometChip® assay in TK6 cells to evaluate three model agents: nitrofurantoin (NIT), metronidazole (MTZ), and novobiocin (NOV). TGx-DDI was analyzed by two independent labs and technologies (nCounter® and TempO-Seq®). Although these anti-infective drugs are, or have been, used in human and/or veterinary medicine, the standard genotoxicity testing battery showed significant genetic safety findings. Specifically, NIT is a mutagen and causes chromosome damage, and MTZ and NOV cause chromosome damage in conventional in vitro tests. Herein, the TGx-DDI biomarker classified NIT and MTZ as non-DDI at all concentrations tested, suggesting that NIT's mutagenic activity is bacterial specific and that the observed chromosome damage by MTZ might be a consequence of in vitro test conditions. In contrast, NOV was classified as DDI at the second highest concentration tested, which is in line with the fact that NOV is a bacterial DNA-gyrase inhibitor that also affects topoisomerase II at high concentrations. The lack of DNA damage for NIT and MTZ was confirmed by the CometChip® results, which were negative for all three drugs except at overtly cytotoxic concentrations. This case study demonstrates the utility of combining the TGx-DDI biomarker and CometChip® to resolve conflicting genotoxicity data and provides further validation to support the reproducibility of the biomarker.

15.
Toxicol Sci ; 190(2): 127-132, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36165699

RESUMO

Use of molecular data in human and ecological health risk assessments of industrial chemicals and agrochemicals has been anticipated by the scientific community for many years; however, these data are rarely used for risk assessment. Here, a logic framework is proposed to explore the feasibility and future development of transcriptomic methods to refine and replace the current apical endpoint-based regulatory toxicity testing paradigm. Four foundational principles are outlined and discussed that would need to be accepted by stakeholders prior to this transformative vision being realized. Well-supported by current knowledge, the first principle is that transcriptomics is a reliable tool for detecting alterations in gene expression that result from endogenous or exogenous influences on the test organism. The second principle states that alterations in gene expression are indicators of adverse or adaptive biological responses to stressors in an organism. Principle 3 is that transcriptomics can be employed to establish a benchmark dose-based point of departure (POD) from short-term, in vivo studies at a dose level below which a concerted molecular change (CMC) is not expected. Finally, Principle 4 states that the use of a transcriptomic POD (set at the CMC dose level) will support a human health-protective risk assessment. If all four principles are substantiated, this vision is expected to transform aspects of the industrial chemical and agrochemical risk assessment process that are focused on establishing safe exposure levels for mammals across numerous toxicological contexts resulting in a significant reduction in animal use while providing equal or greater protection of human health. Importantly, these principles and approaches are also generally applicable for ecological safety assessment.


Assuntos
Testes de Toxicidade , Transcriptoma , Animais , Humanos , Medição de Risco/métodos , Benchmarking , Mamíferos
16.
Toxicol Sci ; 188(1): 4-16, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35404422

RESUMO

There is growing recognition across broad sectors of the scientific community that use of genomic biomarkers has the potential to reduce the need for conventional rodent carcinogenicity studies of industrial chemicals, agrochemicals, and pharmaceuticals through a weight-of-evidence approach. These biomarkers fall into 2 major categories: (1) sets of gene transcripts that can identify distinct tumorigenic mechanisms of action; and (2) cancer driver gene mutations indicative of rapidly expanding growth-advantaged clonal cell populations. This call-to-action article describes a collaborative approach launched to develop and qualify biomarker gene expression panels that measure widely accepted molecular pathways linked to tumorigenesis and their activation levels to predict tumorigenic doses of chemicals from short-term exposures. Growing evidence suggests that application of such biomarker panels in short-term exposure rodent studies can identify both tumorigenic hazard and tumorigenic activation levels for chemical-induced carcinogenicity. In the future, this approach will be expanded to include methodologies examining mutations in key cancer driver gene mutation hotspots as biomarkers of both genotoxic and nongenotoxic chemical tumor risk. Analytical, technical, and biological validation studies of these complementary genomic tools are being undertaken by multisector and multidisciplinary collaborative teams within the Health and Environmental Sciences Institute. Success from these efforts will facilitate the transition from current heavy reliance on conventional 2-year rodent carcinogenicity studies to more rapid animal- and resource-sparing approaches for mechanism-based carcinogenicity evaluation supporting internal and regulatory decision-making.


Assuntos
Neoplasias , Roedores , Animais , Biomarcadores Tumorais/genética , Carcinogênese , Testes de Carcinogenicidade , Carcinógenos/toxicidade , Genômica , Neoplasias/induzido quimicamente , Neoplasias/genética
17.
PLoS One ; 17(1): e0261853, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35025926

RESUMO

Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is used worldwide to test and trace the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). "Extraction-less" or "direct" real time-reverse transcription polymerase chain reaction (RT-PCR) is a transparent and accessible qualitative method for SARS-CoV-2 detection from nasopharyngeal or oral pharyngeal samples with the potential to generate actionable data more quickly, at a lower cost, and with fewer experimental resources than full RT-qPCR. This study engaged 10 global testing sites, including laboratories currently experiencing testing limitations due to reagent or equipment shortages, in an international interlaboratory ring trial. Participating laboratories were provided a common protocol, common reagents, aliquots of identical pooled clinical samples, and purified nucleic acids and used their existing in-house equipment. We observed 100% concordance across laboratories in the correct identification of all positive and negative samples, with highly similar cycle threshold values. The test also performed well when applied to locally collected patient nasopharyngeal samples, provided the viral transport media did not contain charcoal or guanidine, both of which appeared to potently inhibit the RT-PCR reaction. Our results suggest that direct RT-PCR assay methods can be clearly translated across sites utilizing readily available equipment and expertise and are thus a feasible option for more efficient COVID-19 coronavirus disease testing as demanded by the continuing pandemic.


Assuntos
Teste para COVID-19/métodos , COVID-19/diagnóstico , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Transcrição Reversa/genética , SARS-CoV-2/genética , COVID-19/virologia , Estudos de Viabilidade , Humanos , Nasofaringe/virologia , Pandemias/prevenção & controle , Sensibilidade e Especificidade , Testes Sorológicos/métodos , Manejo de Espécimes/métodos
18.
Int J Toxicol ; 30(3): 272-86, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21527643

RESUMO

There are several recent examples where clinically significant, safety-related, drug effects on hemodynamics or cardiac function were not apparent until large clinical trials were completed or the drugs entered the consumer market. Such late-stage safety issues can have significant impact on patient health and consumer confidence, as well as ramifications for the regulatory, pharmaceutical, and financial communities. This manuscript provides recommendations that evolved from a 2009 HESI workshop on the need for improved translation of nonclinical cardiovascular effects to the clinical arena. The authors conclude that expanded and improved efforts to perform sensitive yet specific evaluations of functional cardiovascular parameters in nonclinical studies will allow pharmaceutical companies to identify suspect drugs early in the discovery and development process while allowing promising drugs to proceed into clinical development.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Coração/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Humanos
19.
Front Allergy ; 2: 700533, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35386979

RESUMO

Motivation: The availability of databases identifying allergenic proteins via a transparent and consensus-based scientific approach is of prime importance to support the safety review of genetically-modified foods and feeds, and public safety in general. Over recent years, screening for potential new allergens sequences has become more complex due to the exponential increase of genomic sequence information. To address these challenges, an international collaborative scientific group coordinated by the Health and Environmental Sciences Institute (HESI), was tasked to develop a contemporary, adaptable, high-throughput process to build the COMprehensive Protein Allergen REsource (COMPARE) database, a publicly accessible allergen sequence data resource along with bioinformatics analytical tools following guidelines of FAO/WHO and CODEX Alimentarius Commission. Results: The COMPARE process is novel in that it involves the identification of candidate sequences via automated keyword-based sorting algorithm and manual curation of the annotated sequence entries retrieved from public protein sequence databases on a yearly basis; its process is meant for continuous improvement, with updates being transparently documented with each version; as a complementary approach, a yearly key-word based search of literature databases is added to identify new allergen sequences that were not (yet) submitted to protein databases; in addition, comments from the independent peer-review panel are posted on the website to increase transparency of decision making; finally, sequence comparison capabilities associated with the COMPARE database was developed to evaluate the potential allergenicity of proteins, based on internationally recognized guidelines, FAO/WHO and CODEX Alimentarius Commission.

20.
medRxiv ; 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33880478

RESUMO

Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is used worldwide to test and trace the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). "Extraction-less" or "direct" real time-reverse transcription polymerase chain reaction (RT-PCR) is an open-access qualitative method for SARS-CoV-2 detection from nasopharyngeal or oral pharyngeal samples with the potential to generate actionable data more quickly, at a lower cost, and with fewer experimental resources than full RT-qPCR. This study engaged 10 global testing sites, including laboratories currently experiencing testing limitations due to reagent or equipment shortages, in an international interlaboratory ring trial. Participating laboratories were provided a common protocol, common reagents, aliquots of identical pooled clinical samples, and purified nucleic acids and used their existing in-house equipment. We observed 100% concordance across laboratories in the correct identification of all positive and negative samples, with highly similar cycle threshold values. The test also performed well when applied to locally collected patient nasopharyngeal samples, provided the viral transport media did not contain charcoal or guanidine, both of which appeared to potently inhibit the RT-PCR reaction. Our results suggest that open-access, direct RT-PCR assays are a feasible option for more efficient COVID-19 coronavirus disease testing as demanded by the continuing pandemic.

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