Fit-for-Purpose Ki-67 Immunohistochemistry Assays for Breast Cancer.

New therapies are being developed for breast cancer, and in this process, some "old" biomarkers are reutilized and given a new purpose. It is not always recognized that by changing a biomarker's intended use, a new biomarker assay is created. The Ki-67 biomarker is typically assessed by immunohistochemistry (IHC) to provide a proliferative index in breast cancer. Canadian laboratories assessed the analytical performance and diagnostic accuracy of their Ki-67 IHC laboratory-developed tests (LDTs) of relevance for the LDTs' clinical utility. Canadian clinical IHC laboratories enrolled in the Canadian Biomarker Quality Assurance Pilot Run for Ki-67 in breast cancer by invitation. The Dako Ki-67 IHC pharmDx assay was employed as a study reference assay. The Dako central laboratory was the reference laboratory. Participants received unstained slides of breast cancer tissue microarrays with 32 cases and performed their in-house Ki-67 assays. The results were assessed using QuPath, an open-source software application for bioimage analysis. Positive percent agreement (PPA, sensitivity) and negative percent agreement (NPA, specificity) were calculated against the Dako Ki-67 IHC pharmDx assay for 5%, 10%, 20%, and 30% cutoffs. Overall, PPA and NPA varied depending on the selected cutoff; participants were more successful with 5% and 10%, than with 20% and 30% cutoffs. Only 4 of 16 laboratories had robust IHC protocols with acceptable PPA for all cutoffs. The lowest PPA for the 5% cutoff was 85%, for 10% was 63%, for 20% was 14%, and for 30% was 13%. The lowest NPA for the 5% cutoff was 50%, for 10% was 33%, for 20% was 50%, and for 30% was 57%. Despite many years of international efforts to standardize IHC testing for Ki-67 in breast cancer, our results indicate that Canadian clinical LDTs have a wide analytical sensitivity range and poor agreement for 20% and 30% cutoffs. The poor agreement was not due to the readout but rather due to IHC protocol conditions. International Ki-67 in Breast Cancer Working Group (IKWG) recommendations related to Ki-67 IHC standardization cannot take full effect without reliable fit-for-purpose reference materials that are required for the initial assay calibration, assay performance monitoring, and proficiency testing.

Contemporary Practice and Considerations for Real-World Data Source Identification and Feasibility Assessment.

PURPOSE: There has been rapid growth in the variety and number of real-world data (RWD) sources, as well as the number of regulatory documents that provide guidance for assessing the suitability of RWD sources for pharmacoepidemiology studies. This study aims to assess differences in RWD guidance and variability in current practice for identifying and assessing RWD for studies with regulatory purpose. METHODS: Key criteria for feasibility assessment were mapped against relevant regulatory guidance documents across US, EU, and Asia-Pacific regions. An online survey was designed and deployed to International Society for Pharmacoepidemiology members to understand current practice. Findings were summarized and used to inform key considerations and recommendations. RESULTS: Eleven RWD guidance documents were identified and mapped against 14 RWD assessment criteria. Variability was seen across these documents in guidance for these criteria. Between December 2022 and January 2023, 37 survey respondents reported having used RWD for post-marketing commitments (34, 92%) and/or background epidemiology (28, 76%). RWD were mostly identified through literature (33, 89%) and data landscaping (26, 70%); guidance documents referenced included: Food and Drug Administration (20, 54%), European Network for Centres for Pharmacoepidemiology and Pharmacovigilance (17, 46%), European Medical Agency (16, 43%), and Structured Process to Identify Fit-For-Purpose Data (11, 30%). Challenges for conducting feasibility assessments included RWD accessibility, ability to complete validation, and RWD provider responsiveness. CONCLUSIONS: Existing guidelines are used extensively by researchers, but key criteria for RWD identification and feasibility assessment are not reflected consistently and challenges remain. Recommendations have been made reflecting study findings.

Using validity theory and psychometrics to evaluate and support expanded uses of existing scales.

BACKGROUND: Scale development is a complex activity requiring significant investments of time and money to produce evidence of a scale's ability to produce reliable scores and valid inferences. With increasing use of clinical outcome assessments (COAs) in medical product development, evidentiary expectations of regulatory bodies to support inferences are a key consideration. The goal of this paper is to demonstrate how existing methods in measurement science can be used to identify and fill evidence gaps when considering re-purposing an existing scale for a new use case (e.g., new patient population, altering the recall period), rather than creating a new COA tool. METHODS: We briefly review select validity theory and psychometric concepts, linking them to the nomenclature in the COA/regulated space. Four examples (two in-text and two in online supplemental materials) of modifications are presented to demonstrate these ideas in practice for quality of life (QOL)-related measures. RESULTS: Each example highlights the initial process of evaluating the desired validity claims, identifying gaps in evidence to support these claims, and determining how such gaps could be filled, often without having to develop a new measure. CONCLUSIONS: If an existing scale, with minimal modification or additional evidence, can be shown to be fit for a new purpose, considerable effort can be saved and research waste avoided. In many cases, a new instrument is simply unnecessary. Far better to recycle an "old" scale for a new use-with sufficient evidence that it is fit for that purpose-than to "buy" a new one.

Stormwater treatment for reuse: Current practice and future development - A review.

Stormwater harvesting is an effective measure to mitigate flooding risk and pollutant migration in our urban environment with the continuously increasing impermeable faction. Treatment of harvested stormwater also provides the fit-for-purpose water sources as an alternative to potable water supply ensuring the reliability and sustainability of the water management in the living complex. In order to provide the water management decision-maker with a broad range of related technology database and to facilitate the implementation of stormwater harvesting in the future, a comprehensive review was undertaken to understand the corresponding treatment performance, the applicable circumstances of current stormwater treatment and harvesting technologies. Technologies with promising potential for stormwater treatment were also reviewed to investigate the feasibility of being used in an integrated process. The raw stormwater quality and the required quality for different levels of stormwater reuses (irrigation, recreational, and potable) were reviewed and compared. The required level of treatment is defined for different 'fit-for-purpose' uses of harvested stormwater. Stormwater biofilter and constructed wetland as the two most advanced and widely used stormwater harvesting and treatment technologies, their main functionality, treatment performance and adequate scale of the application were reviewed based on published peer-reviewed articles and case studies. Excessive microbial effluent that exists in stormwater treated using these two technologies has restricted the stormwater reuse in most cases. Water disinfection technologies developed for wastewater and surface water treatment but with high potential to be used for stormwater treatment have been reviewed. Their feasibility and limitation for stormwater treatment are presented with respect to different levels of fit-for-purpose reuses. Implications for future implementation of stormwater treatment are made on proposing treatment trains that are suitable for different fit-for-purpose stormwater reuses.

A human receptor occupancy assay to measure anti-PD-1 binding in patients with prior anti-PD-1.

Receptor occupancy (RO) assessment by flow cytometry is an important pharmacodynamic (PD) biomarker in the clinical development of large molecules such as monoclonal therapeutic antibodies (mAbs). The total-drug-bound RO assay format directly assesses mAb binding to cell surface targets using anti-drug detection antibodies. Here, we generated a flow cytometry detection antibody specifically binding to mAbs of the IgG1 P329GLALA backbone. Using this reagent, we developed a total-drug-bound RO assay format for RG7769, a bi-specific P329GLALA containing mAb targeting PD-1 and TIM3 on T cells. In its fit-for-purpose validated version, this RO assay has been used in the Phase-I dose escalation study of RG7769, informing on peripheral T cell RO and RG7769 antibody binding capacity (ABC). We assessed RG7769 RO in checkpoint-inhibitor (CPI) naïve patients and anti-PD-1 CPI experienced patients using our novel assay. Here, we show that in both groups, complete T cell RO can be achieved (~100%). However, we found that the maximum number of T cell binding sites for RG7769 pre-dosing was roughly twofold lower in patients recently having undergone anti-PD-1 treatment. We show that this is due to steric hindrance exerted by competing mAbs masking the available drug binding sites. Our findings highlight the importance of quantitative mAb assessment in addition to relative RO especially in the context of patients who have previously received anti-PD-1 treatment.

Validation, certification and registration of veterinary diagnostic test kits by the World Organisation for Animal Health Secretariat for Registration of Diagnostic Kits.

In the field of diagnostic test validation, World Organisation for Animal Health (OIE) Reference Laboratories (RLs) have a pivotal role and provide the international community with impartial advice and support in the selection, development and validation of diagnostic tests, which can be applied to the specialist diseases for which they are designated. National RLs provide an invaluable function in supporting the introduction, ongoing validation and application of validated diagnostic tests in line with international standards. Experienced staff with extensive knowledge of such systems and access to specialist facilities for conducting work are available to monitor changes or advancements in technology. They consider their relevance and value to evolving diagnostic test requirements. Reference Laboratories often have a broad mandate of activity linking research or development programmes and surveillance activities to benefit the continual assessment and, if necessary, improvement of diagnostic tools. Reference Laboratories maintain or have access to unique biological archives (known positive and negative sample populations) and produce international reference standards, both of which are vital in establishing the necessary and detailed validation of any diagnostic test. Reference Laboratories act either singularly or in collaborative partnerships with other RLs or science institutes, but also, when required, and with impartiality, with the commercial sector, to ensure new tests are validated according to OIE standards. They promote and apply formal programmes of quality assurance (including proficiency testing programmes) for newly validated tests, ensuring ongoing monitoring and compliance with standards, or as required set out any limitations or uncertainties. Reference Laboratories publish information on test validation in the scientific literature and on relevant websites, as well as disseminating information at workshops and international conferences. Furthermore, they can offer training in the processes and systems underpinning test validation.

Dans le domaine de la validation des tests de diagnostic, les Laboratoires de référence de l'Organisation mondiale de la santé animale (OIE) jouent un rôle central et fournissent à la communauté internationale des conseils impartiaux ainsi qu'un soutien pour la sélection, la mise au point et la validation des tests de diagnostic utilisés pour la détection des maladies correspondant à leur domaine de spécialisation. Les Laboratoires de référence nationaux remplissent une fonction inestimable en facilitant l'introduction, la validation continue et l'application de tests de diagnostic validés conformément aux normes internationales. Ces laboratoires sont dotés de personnels expérimentés possédant une connaissance approfondie de ces systèmes et qui ont accès à des installations spécialisées pour mener à bien leurs opérations et suivre de près les changements ou les avancées technologiques. Ils peuvent ainsi examiner leur pertinence et intérêt au regard de l'évolution des exigences relatives aux tests de diagnostic. Le mandat des Laboratoires de référence recouvre souvent un large éventail d'activités reliant les programmes de recherche ou développement et les activités de surveillance, ce qui permet de réaliser une évaluation continue des outils diagnostiques et, si besoin, de procéder à leur amélioration. Les Laboratoires de référence entretiennent ou ont accès à des banques de matériels biologiques uniques (panels d'échantillons positifs et négatifs connus) et produisent des réactifs de référence internationale, deux catégories de matériels essentielles pour procéder à la validation point par point d'un test diagnostique suivant les critères requis. Les Laboratoires de référence interviennent individuellement ou en partenariat avec d'autres Laboratoires de référence ou instituts scientifiques, mais aussi, lorsque c'est nécessaire et dans le respect des règles d'impartialité, avec le secteur privé, afin de s'assurer que les nouveaux tests sont validés conformément aux normes de l'OIE. Ils soutiennent et appliquent des programmes officiels d'assurance de la qualité (y compris en participant à des programmes d'essais d'aptitude inter-laboratoires) pour les tests nouvellement validés et garantissent leur suivi continu ainsi que leur conformité avec les normes, ou, suivant les cas, définissent les limites ou le niveau d'incertitude à prendre en considération. Les Laboratoires de référence publient les données relatives à la validation des tests dans des journaux scientifique et sur les sites Web pertinents et diffusent également des informations sur le sujet lors d'ateliers et de conférences internationales. En outre, ils peuvent proposer des formations sur les procédures et les systèmes qui sous-tendent la validation des tests.

En el terreno de la validación de pruebas de diagnóstico, los Laboratorios de Referencia de la Organización Mundial de Sanidad Animal (OIE) cumplen una función central y proporcionan a la comunidad internacional servicios de apoyo y asesoramiento imparcial para la selección, el desarrollo y la validación de pruebas de diagnóstico, que pueden aplicarse a la enfermedad para la que cada laboratorio esté designado. Los laboratorios de referencia nacionales cumplen una inestimable función de apoyo a la implantación, la continua validación y la utilización de pruebas de diagnóstico validadas con arreglo a las normas internacionales. Disponen de personal experimentado y muy buen conocedor de estos sistemas y de acceso a instalaciones especializadas de trabajo, lo que les permite seguir de cerca los cambios o adelantos tecnológicos y estudiar su utilidad o interés en relación con la evolución de los requisitos de las pruebas de diagnóstico. Los Laboratorios de Referencia suelen tener un mandato amplio, que a los programas de investigación y desarrollo aúna actividades de vigilancia, en aras de la continua evaluación y, en caso necesario, mejora de las herramientas de diagnóstico. Estos laboratorios poseen (o tienen acceso a) archivos biológicos únicos (conjuntos de muestras probadamente positivas y negativas) y elaboran patrones de referencia internacional, elementos ambos indispensables para llevar a buen fin la necesaria validación detallada de toda prueba de diagnóstico. Los Laboratorios de Referencia pueden trabajar en solitario o en colaboración con otros Laboratorios de Referencia, con institutos científicos e incluso, cuando hace falta, y procediendo con imparcialidad, con entidades del sector privado, a fin de garantizar que toda nueva prueba sea validada con arreglo a las normas de la OIE. También promueven y llevan adelante programas oficiales de garantía de la calidad de pruebas recién validadas (incluidos programas de pruebas de competencia), lo que asegura un seguimiento continuo y el cumplimiento de la normativa en todo momento, o fijan, cuando es necesario, limitaciones o niveles de incertidumbre. Asimismo, estos laboratorios publican datos sobre la validación de pruebas en revistas científicas y sitios web conexos y difunden información al respecto en talleres y conferencias internacionales. Además, pueden impartir formación sobre los procesos y sistemas que fundamentan la validación de pruebas de diagnóstico.

The role of fit-for-purpose assays within tiered testing approaches: A case study evaluating prioritized estrogen-active compounds in an in vitro human uterotrophic assay.

Chemical risk assessment relies on toxicity tests that require significant numbers of animals, time and costs. For the >30,000 chemicals in commerce, the current scale of animal testing is insufficient to address chemical safety concerns as regulatory and product stewardship considerations evolve to require more comprehensive understanding of potential biological effects, conditions of use, and associated exposures. We demonstrate the use of a multi-level new approach methodology (NAMs) strategy for hazard- and risk-based prioritization to reduce animal testing. A Level 1/2 chemical prioritization based on estrogen receptor (ER) activity and metabolic activation using ToxCast data was used to select 112 chemicals for testing in a Level 3 human uterine cell estrogen response assay (IKA assay). The Level 3 data were coupled with quantitative in vitro to in vivo extrapolation (Q-IVIVE) to support bioactivity determination (as a surrogate for hazard) in a tissue-specific context. Assay AC50s and Q-IVIVE were used to estimate human equivalent doses (HEDs), and HEDs were compared to rodent uterotrophic assay in vivo-derived points of departure (PODs). For substances active both in vitro and in vivo, IKA assay-derived HEDs were lower or equivalent to in vivo PODs for 19/23 compounds (83%). Activity exposure relationships were calculated, and the IKA assay was as or more protective of human health than the rodent uterotrophic assay for all IKA-positive compounds. This study demonstrates the utility of biologically relevant fit-for-purpose assays and supports the use of a multi-level strategy for chemical risk assessment.

Quality Governance in Biomedical Research.

Quality research data are essential for quality decision-making and thus for unlocking true innovation potential to ultimately help address unmet medical needs.The factors influencing quality are diverse. They depend on institution type and experiment type and can be of both technical and cultural nature. A well-thought-out governance mechanism will help understand, monitor, and control research data quality in a research institution.In this chapter we provide practical guidance for simple, effective, and sustainable quality governance, tailored to the needs of an organization performing nonregulated preclinical research and owned by all stakeholders.GLP regulations have been developed as a managerial framework under which nonclinical safety testing of pharmaceutical and other products should be conducted. One could argue whether these regulations should be applied to all nonclinical biomedical studies. However, the extensive technical requirements of GLP may not always be fit to the wide variety of studies outside the safety arena and may be seen as overly prescriptive and bureaucratic. In addition, GLP regulations do not take into account scientific excellence in terms of study design or adequacy of analytical methods. For these reasons and in order to allow a lean and fit for purpose approach, the content of this chapter is independent from GLP. Nevertheless, certain topics covered by GLP can be seen as valuable across biomedical research. Examples are focus on transparency and the importance of clear roles and responsibilities for different functions participating in a study.

The gulf between emergency plans and the resources needed: a global review.

Preparedness for an animal emergency event reduces a country's economic and production losses and decreases animal disease threats to neighbouring countries. Investing in animal disease preparedness reduces economic expenditures during an emergency as well as in recovery. An essential component of animal disease preparedness is a national contingency plan that is fit for purpose. This useful document should be frequently updated and can be modified with new information from self-assessments and after-action reports, which should identify resource needs and improvements to be made. National contingency plans are recommended in global international guidance and by animal health and veterinary organisations. Despite this, some countries lack national contingency plans that are fit for purpose, or the resources to implement them. This review concentrates on trends in national contingency planning around the world. In 2018 and 2019, the authors surveyed existing global animal disease contingency plans. Of the 181 Members of the World Organisation for Animal Health (OIE), 163 were reported to have some form of national contingency plan. (Over the course of the review from 2018 to 2019, the 182nd Member joined the OIE. This review examines only the 181 that were Members when the survey began.) The authors review current global animal emergency preparedness and discuss the gaps that have been identified. They discuss global trends, examining developing concepts and novel approaches that may aid improvements in global national contingency planning and enhance the global capacity to prepare for animal disease where gaps exist.

La préparation aux urgences de santé animale atténue les pertes économiques et productives des pays affectés et réduit la menace de propagation de maladies aux pays voisins. Les investissements dédiés à la préparation aux maladies animales réduisent les dépenses économiques durant l'urgence ainsi que pendant la phase de redressement. L'une des composantes essentielles de la préparation aux situations d'urgence zoosanitaire est le plan national d'intervention, qui doit être adapté aux objectifs visés. Il convient de mettre à jour régulièrement ce document de programmation et de le modifier au vu des renseignements nouveaux émanant des autoévaluations ou des rapports postérieurs à l'adoption de mesures ­ lesquels doivent préciser les ressources requises et les améliorations à apporter. Les directives internationales et les organisations vétérinaires et de santé animale recommandent de se doter de plans nationaux d'intervention d'urgence. Pourtant, certains pays ne disposent ni de plans nationaux d'intervention adaptés aux objectifs visés, ni des ressources nécessaires à leur mise en œuvre. L'analyse présentée par les auteurs est axée sur les tendances observées dans le monde en matière de planification nationale des interventions d'urgence. En 2018 et 2019, les auteurs ont fait le point sur les plans d'urgence existants dans le domaine de la santé animale. Il ressort de leur enquête que 163 des 181 Membres de l'Organisation mondiale de la santé animale (OIE) disposaient d'un plan national d'urgence, sous une forme ou une autre. (Au cours de cette enquête conduite de 2018 à 2019, un 182e Membre a adhéré à l'OIE. L'analyse présentée par les auteurs ne concerne que les 181 pays ayant la qualité de Membre au début de l'enquête.) Les auteurs passent en revue le niveau actuel de préparation aux urgences zoosanitaires dans le monde et analysent les lacunes constatées. Ils évoquent les tendances mondiales et soulignent les concepts en cours d'élaboration ainsi que les approches novatrices susceptibles de contribuer à l'amélioration des plans nationaux d'intervention d'urgence à l'échelle mondiale et au renforcement des capacités de préparation aux maladies animales dans les pays où des lacunes existent encore.

La preparación para episodios de emergencia relacionados con los animales reduce las pérdidas económicas y de producción que sufre un país y rebaja el nivel de las amenazas zoosanitarias que pesan sobre los países vecinos. El hecho de invertir en la preparación para enfermedades animales reduce los gastos no solo cuando adviene la emergencia, sino también durante la fase de recuperación. Uno de los componentes básicos de este proceso de preparación es un plan nacional de emergencia que esté adaptado a su finalidad. Se trata de un documento muy útil, que conviene actualizar con frecuencia y puede ser enriquecido a medida que los procesos de autoevaluación y los informes retrospectivos (que ayudan a determinar los recursos necesarios y las mejoras requeridas) vayan deparando nueva información. Tanto las guías internacionales de ámbito mundial como las organizaciones de sanidad animal y veterinaria recomiendan disponer de un plan nacional de emergencia. Pese a ello, hay países que carecen de un plan de este tipo adaptado a sus fines o de los recursos necesarios para ponerlo en práctica. Los autores se centran aquí en las tendencias en todo el mundo de los procesos de elaboración de planes nacionales de emergencia. En 2018 y 2019 examinaron los planes para emergencias zoosanitarias existentes en el mundo y constataron que, de los 181 Países Miembros de la Organización Mundial de Sanidad Animal (OIE), 163 disponen de algún tipo de plan nacional de emergencia. (Entre 2018 y 2019, en el curso del estudio, un nuevo País Miembro, el 182º, se incorporó a la OIE, pero los resultados aquí descritos se refieren solo a los 181 que eran Miembros cuando empezó el estudio.) Los autores describen la situación mundial actual en cuanto a preparación para emergencias relacionadas con los animales y señalan las carencias detectadas. Después exponen las tendencias de ámbito mundial, examinando conceptos nacientes y planteamientos novedosos que pueden ayudar a mejorar la elaboración en el mundo de planes nacionales de emergencia y a reforzar la capacidad general de preparación para enfermedades animales allí donde existen deficiencias.

A combined simulation-optimisation modelling framework for assessing the energy use of urban water systems.

Reliance on new and alternative water supply sources is a desirable option for upgrading existing and ageing urban water system infrastructure that is no longer able to cater for steadily increasing water demand. This transformation will increasingly involve the use of decentralised, more complex and energy intensive urban water systems. Modelling capability that takes a holistic systems approach to optimize the dynamic interactions between water and energy is needed to evaluate the performance of fit-for-purpose water supply systems for the urban sector. This paper presents a simulation-optimisation model to concurrently simulate and optimize an urban water supply system based on minimum energy use when water of alternative quality is supplied to different users on a 'fit-for-purpose' basis. The model uses a System Dynamics approach to simulate the energy use of different water supply systems in the form of stocks and flows combined with a Genetic Algorithm (GA) technique to optimize energy use while satisfying all the water demands. The comprehensive model framework is built on a Matlab/Simulink® platform. Life Cycle Energy Assessment (LCEA) is used to generate the embodied energy use variables which are input to the simulation-optimisation model. The model is sufficiently flexible to accommodate water supply systems of variable spatial scales and analyse water and energy use at variable time scales. The application of the modelling framework on the Aurora urban development estate, Australia, shows that the model produces essential information about the water supply and energy use intensity according to specified criteria.

ExpoQual: Evaluating measured and modeled human exposure data.

Recent rapid technological advances are producing exposure data sets for which there are no available data quality assessment tools. At the same time, regulatory agencies are moving in the direction of data quality assessment for environmental risk assessment and decision-making. A transparent and systematic approach to evaluating exposure data will aid in those efforts. Any approach to assessing data quality must consider the level of quality needed for the ultimate use of the data. While various fields have developed approaches to assess data quality, there is as yet no general, user-friendly approach to assess both measured and modeled data in the context of a fit-for-purpose risk assessment. Here we describe ExpoQual, an instrument developed for this purpose which applies recognized parameters and exposure data quality elements from existing approaches for assessing exposure data quality. Broad data streams such as quantitative measured and modeled human exposure data as well as newer and developing approaches can be evaluated. The key strength of ExpoQual is that it facilitates a structured, reproducible and transparent approach to exposure data quality evaluation and provides for an explicit fit-for-purpose determination. ExpoQual was designed to minimize subjectivity and to include transparency in aspects based on professional judgment. ExpoQual is freely available on-line for testing and user feedback (exposurequality.com).

The contribution of lot-to-lot variation to the measurement uncertainty of an LC-MS-based multi-mycotoxin assay.

Multi-mycotoxin determination by LC-MS is commonly based on external solvent-based or matrix-matched calibration and, if necessary, the correction for the method bias. In everyday practice, the method bias (expressed as apparent recovery RA), which may be caused by losses during the recovery process and/or signal/suppression enhancement, is evaluated by replicate analysis of a single spiked lot of a matrix. However, RA may vary for different lots of the same matrix, i.e., lot-to-lot variation, which can result in a higher relative expanded measurement uncertainty (U r ). We applied a straightforward procedure for the calculation of U r from the within-laboratory reproducibility, which is also called intermediate precision, and the uncertainty of RA (ur,RA). To estimate the contribution of the lot-to-lot variation to U r , the measurement results of one replicate of seven different lots of figs and maize and seven replicates of a single lot of these matrices, respectively, were used to calculate U r . The lot-to-lot variation was contributing to ur,RA and thus to U r for the majority of the 66 evaluated analytes in both figs and maize. The major contributions of the lot-to-lot variation to ur,RA were differences in analyte recovery in figs and relative matrix effects in maize. U r was estimated from long-term participation in proficiency test schemes with 58%. Provided proper validation, a fit-for-purpose U r of 50% was proposed for measurement results obtained by an LC-MS-based multi-mycotoxin assay, independent of the concentration of the analytes.

Animal Models of Seizures and Epilepsy: Past, Present, and Future Role for the Discovery of Antiseizure Drugs.

The identification of potential therapeutic agents for the treatment of epilepsy requires the use of seizure models. Except for some early treatments, including bromides and phenobarbital, the antiseizure activity of all clinically used drugs was, for the most part, defined by acute seizure models in rodents using the maximal electroshock and subcutaneous pentylenetetrazole seizure tests and the electrically kindled rat. Unfortunately, the clinical evidence to date would suggest that none of these models, albeit useful, are likely to identify those therapeutics that will effectively manage patients with drug resistant seizures. Over the last 30 years, a number of animal models have been developed that display varying degrees of pharmacoresistance, such as the phenytoin- or lamotrigine-resistant kindled rat, the 6-Hz mouse model of partial seizures, the intrahippocampal kainate model in mice, or rats in which spontaneous recurrent seizures develops after inducing status epilepticus by chemical or electrical stimulation. As such, these models can be used to study mechanisms of drug resistance and may provide a unique opportunity for identifying a truly novel antiseizure drug (ASD), but thus far clinical evidence for this hope is lacking. Although animal models of drug resistant seizures are now included in ASD discovery approaches such as the ETSP (epilepsy therapy screening program), it is important to note that no single model has been validated for use to identify potential compounds for as yet drug resistant seizures, but rather a battery of such models should be employed, thus enhancing the sensitivity to discover novel, highly effective ASDs. The present review describes the previous and current approaches used in the search for new ASDs and offers some insight into future directions incorporating new and emerging animal models of therapy resistance.

Pathway Based Toxicology and Fit-for-Purpose Assays.

The field of toxicity testing for non-pharmaceutical chemicals is in flux with multiple initiatives in North America and the EU to move away from animal testing to mode-of-action based in vitro assays. In this arena, there are still obstacles to overcome, such as developing appropriate cellular assays, creating pathway-based dose-response models and refining in vitro-in vivo extrapolation (IVIVE) tools. Overall, it is necessary to provide assurances that these new approaches are adequately protective of human and ecological health. Another major challenge for individual scientists and regulatory agencies is developing a cultural willingness to shed old biases developed around animal tests and become more comfortable with mode-of-action based assays in human cells. At present, most initiatives focus on developing in vitro alternatives and assessing how well these alternative methods reproduce past results related to predicting organism level toxicity in intact animals. The path forward requires looking beyond benchmarking against high dose animal studies. We need to develop targeted cellular assays, new cell biology-based extrapolation models for assessing regions of safety for chemical exposures in human populations, and mode-of-action-based approaches which are constructed on an understanding of human biology. Furthermore, it is essential that assay developers have the flexibility to 'validate' against the most appropriate mode-of-action data rather than against apical endpoints in high dose animal studies. This chapter demonstrates the principles of fit-for-purpose assay development using pathway-targeted case studies. The projects include p53-mdm2-mediated DNA-repair, estrogen receptor-mediated cell proliferation and PPARα receptor-mediated liver responses.

Analytical procedure validation and the quality by design paradigm.

Since the adoption of the ICH Q8 document concerning the development of pharmaceutical processes following a quality by design (QbD) approach, there have been many discussions on the opportunity for analytical procedure developments to follow a similar approach. While development and optimization of analytical procedure following QbD principles have been largely discussed and described, the place of analytical procedure validation in this framework has not been clarified. This article aims at showing that analytical procedure validation is fully integrated into the QbD paradigm and is an essential step in developing analytical procedures that are effectively fit for purpose. Adequate statistical methodologies have also their role to play: such as design of experiments, statistical modeling, and probabilistic statements. The outcome of analytical procedure validation is also an analytical procedure design space, and from it, control strategy can be set.

Evaluation of a Nursing Intranet Using a Two-Phase Approach.

An intranet is a beneficial tool, most commonly utilised and researched in corporate settings, but can also be found within healthcare. An organisational intranet has many of the same functions as the internet while also having a security firewall associated with it, meaning that only those with security access to the site are able to gain access. An evaluation study, using a two-phase process, of a Nursing Intranet within a healthcare organisation in one urban hospital in New Zealand is presented. First a content audit was undertaken, before using a selected framework to evaluate the content, design and functionality of the Nursing Intranet. The results from this evaluation identified some strengths, but also areas to improve. Further research, including the development of tools to evaluate intranets in a healthcare setting are needed to ensure information is more readily accessible to health professional staff.

In vitro permeation of nicotine and tobacco specific nitrosamines from smokeless tobacco product extracts in a 3D buccal tissue model.

Tobacco product use is a risk factor in the development of oral cancer, although epidemiology studies show this risk is far less with smokeless tobacco product use than cigarette smoking. While smokeless tobacco contains harmful and potentially harmful constituents (HPHCs), the oral permeation of HPHCs in oral tobacco products is not completely understood. To improve the understanding, three different extract concentrations of the CORESTA reference products (CRP) for snus (CRP1.1) and moist snuff (CRP2.1) were applied to cellular tissue derived from two donors of EpiOral™ model, a 3D human buccal model, and permeation of nicotine and tobacco-specific nitrosamines (TSNAs) were measured over two hours. Permeation of 0.15% caffeine in complete artificial saliva and cell viability were also measured. Results showed that a consistent and concentration dependent cumulative permeation of nicotine and TSNAs was observed with high percent recovery in all conditions. A high degree of sensitivity was seen for all analytes, with minimal cytotoxicity for both CRPs. The data presented here show the EpiOral™ model is fit-for-purpose to evaluate the permeation of nicotine and TSNAs in nicotine-containing snus and moist snuff oral tobacco.

Validation of two LCHRMS methods for large-scale untargeted metabolomics of serum samples: Strategy to establish method fitness-for-purpose.

Untargeted metabolomics by LCHRMS is a powerful tool to enhance our knowledge of pathophysiological processes. Whereas validation of a bioanalytical method is customary in most analytical chemistry fields, it is rarely performed for untargeted metabolomics. This study aimed to establish and validate an analytical platform for a long-term, clinical metabolomics study. Sample preparation was performed with an automated liquid handler and four analytical methods were developed and evaluated. The validation study spanned three batches with twelve runs using individual serum samples and various quality control samples. Data was acquired with untargeted acquisition and only metabolites identified at level 1 were evaluated. Validation parameters were set to evaluate key performance metrics relevant for the intended application: reproducibility, repeatability, stability, and identification selectivity, emphasizing dataset intrinsic variance. Concordance of semi-quantitative results between methods was evaluated to identify potential bias. Spearman rank correlation coefficients (rs) were calculated from individual serum samples. Of the four methods tested, two were selected for validation. A total of 47 and 55 metabolites (RPLC-ESI+- and HILIC-ESI--HRMS, respectively) met specified validation criteria. Quality assurance involved system suitability testing, sample release, run release, and batch release. The median repeatability and within-run reproducibility as coefficient of variation% for metabolites that passed validation on RPLC-ESI+- and HILIC-ESI--HRMS were 4.5 and 4.6, and 1.5 and 3.8, respectively. Metabolites that passed validation on RPLC-ESI+-HRMS had a median D-ratio of 1.91, and 89 % showed good signal intensity after ten-fold dilution. The corresponding numbers for metabolites with the HILIC-ESI--HRMS method was 1.45 and 45 %, respectively. The rs median ({range}) for metabolites that passed validation on RPLC-ESI+- was 0.93 (N = 9 {0.69-0.98}) and on HILIC-ESI--HRMS was 0.93 (N = 22 {0.55-1.00}). The validated methods proved fit-for-purpose and the laboratory thus demonstrated its capability to produce reliable results for a large-scale, untargeted metabolomics study. This validation not only bolsters the reliability of the assays but also significantly enhances the impact and credibility of the hypotheses generated from the studies. Therefore, this validation study serves as a benchmark in the documentation of untargeted metabolomics, potentially guiding future endeavors in the field.

An Alternative Rapid Confirmation Method for Identifying Listeria monocytogenes from a Variety of 125 g Food Samples Within Two Days of a PCR Presumptive Positive.

Cultural confirmation following detection of a Listeria monocytogenespresumptive positive can take 3-7 days to finalize; this uncertainty is a point of frustration for food producers needing to make time-sensitive disposition decisions. To address the demand for shortened time-to-results, an alternative L. monocytogenes confirmation method consisting of two components, (i) a secondary screen using a different rapid method, and (ii) concurrent cultural isolation followed by next-day colony identification was evaluated. For the study, four food matrices (hot dogs, peanut butter, frozen vegetables, and multicomponent frozen meals) were inoculated with low levels (0.36-1.39 MPN/125 g) of L. monocytogenes per the AOAC guidelines for a matrix study. Analyses were performed on 125 g test portions and started with a PCR primary screen (Bio-Rad iQ-Check Listeria monocytogenes II). Next, all enriched food samples underwent a secondary screen by bioMérieux's GENE-UP LMO2 Real-Time PCR and VIDAS LMX ELFA along with streaking onto RAPID'L.mono Agar. Presumptive positive L. monocytogenes colonies were identified utilizing a high throughput rapid identification method (Hygiena's BAX System L. monocytogenes Real-Time PCR assay, Neogen's ANSR isothermal nucleic acid amplification assay, and Bruker's MALDI Biotyper). Importantly, this study evaluated multiple commercially available options for the secondary screen (n = 2) and rapid identification (n = 3) to allow for easy adoption by testing laboratories. Overall, there was no statistically significant difference (p ≤ 0.05) between the number of L. monocytogenes-positive 125 g samples obtained by the cultural reference method and the alternative confirmation methods (regardless of which method combinations were evaluated). Additionally, this study supports that, when both the primary and secondary screen methods yield a positive result, the sample could be considered a confirmed positive for L. monocytogenes.

Frameworks, Dimensions, Definitions of Aspects, and Assessment Methods for the Appraisal of Quality of Health Data for Secondary Use: Comprehensive Overview of Reviews.

BACKGROUND: Health care has not reached the full potential of the secondary use of health data because of-among other issues-concerns about the quality of the data being used. The shift toward digital health has led to an increase in the volume of health data. However, this increase in quantity has not been matched by a proportional improvement in the quality of health data. OBJECTIVE: This review aims to offer a comprehensive overview of the existing frameworks for data quality dimensions and assessment methods for the secondary use of health data. In addition, it aims to consolidate the results into a unified framework. METHODS: A review of reviews was conducted including reviews describing frameworks of data quality dimensions and their assessment methods, specifically from a secondary use perspective. Reviews were excluded if they were not related to the health care ecosystem, lacked relevant information related to our research objective, and were published in languages other than English. RESULTS: A total of 22 reviews were included, comprising 22 frameworks, with 23 different terms for dimensions, and 62 definitions of dimensions. All dimensions were mapped toward the data quality framework of the European Institute for Innovation through Health Data. In total, 8 reviews mentioned 38 different assessment methods, pertaining to 31 definitions of the dimensions. CONCLUSIONS: The findings in this review revealed a lack of consensus in the literature regarding the terminology, definitions, and assessment methods for data quality dimensions. This creates ambiguity and difficulties in developing specific assessment methods. This study goes a step further by assigning all observed definitions to a consolidated framework of 9 data quality dimensions.