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Cell adhesion molecules are membrane-bound proteins predominantly expressed in the central nervous system along principal axonal pathways with key roles in nervous system development, neural cell differentiation and migration, axonal growth and guidance, myelination, and synapse formation. Here, we describe ten affected individuals with bi-allelic variants in the neuronal cell adhesion molecule NRCAM that lead to a neurodevelopmental syndrome of varying severity; the individuals are from eight families. This syndrome is characterized by developmental delay/intellectual disability, hypotonia, peripheral neuropathy, and/or spasticity. Computational analyses of NRCAM variants, many of which cluster in the third fibronectin type III (Fn-III) domain, strongly suggest a deleterious effect on NRCAM structure and function, including possible disruption of its interactions with other proteins. These findings are corroborated by previous in vitro studies of murine Nrcam-deficient cells, revealing abnormal neurite outgrowth, synaptogenesis, and formation of nodes of Ranvier on myelinated axons. Our studies on zebrafish nrcamaΔ mutants lacking the third Fn-III domain revealed that mutant larvae displayed significantly altered swimming behavior compared to wild-type larvae (p < 0.03). Moreover, nrcamaΔ mutants displayed a trend toward increased amounts of α-tubulin fibers in the dorsal telencephalon, demonstrating an alteration in white matter tracts and projections. Taken together, our study provides evidence that NRCAM disruption causes a variable form of a neurodevelopmental disorder and broadens the knowledge on the growing role of the cell adhesion molecule family in the nervous system.
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Transtornos do Neurodesenvolvimento , Doenças do Sistema Nervoso Periférico , Animais , Axônios/metabolismo , Adesão Celular/genética , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular Neuronais , Humanos , Camundongos , Hipotonia Muscular/genética , Hipotonia Muscular/metabolismo , Espasticidade Muscular/metabolismo , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismoRESUMO
Venous thromboembolism (VTE) and stroke carry significant mortality and morbidity in cancer patients. Direct oral anticoagulants (DOACs) have been demonstrated to be effective for the treatment of VTE and prevention of stroke in atrial fibrillation (AF). Bleeding rates are variable and are based on the cancer type and the patient's specific risk factors. There are approved specific antidotes for DOAC-associated bleeding. Other strategies are available for bleeding reversal, including the use of prothrombin complex concentrate (PCC). No randomized studies have compared head-to-head the efficacy and safety of reversal agents. We aim to examine the safety and effectiveness of hemostatic agents in cancer patients with DOAC-related major bleeding. A retrospective chart review study of patients at MD Anderson Cancer Center with DOAC-related major bleeding between 2014 and 2019. Bleeding severity and clinical hemostasis were described based on ISTH guidelines and the Sarode criteria, respectively. The rates of thrombotic complications and mortality at 30-day from the index bleeding event were described. We identified 23 patients with DOAC-related major bleeding; 14 patients received PCC and 9 patients received andexanet alfa. The most common sites of bleeding were the gastrointestinal tract and intracranial. Effective hemostasis and 30-day mortality were similar to reported results from other reports of outcomes of reversal agents for DOAC related-bleeding in non-cancer patients. One patient in each treatment group experienced a thrombotic event. Further larger scale studies are needed to confirm our findings in cancer patients.
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Neoplasias , Acidente Vascular Cerebral , Tromboembolia Venosa , Humanos , Anticoagulantes/uso terapêutico , Tromboembolia Venosa/tratamento farmacológico , Estudos Retrospectivos , Hemorragia/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Administração Oral , Neoplasias/tratamento farmacológicoRESUMO
Aquatic eco-neurotoxicology is an emerging field that requires new analytical systems to study the effects of pollutants on animal behaviors. This is especially true if we are to gain insights into one of the least studied aspects: the potential perturbations that neurotoxicants can have on cognitive behaviors. The paucity of experimental data is partly caused by a lack of low-cost technologies for the analysis of higher-level neurological functions (e.g., associative learning) in small aquatic organisms. Here, we present a proof-of-concept prototype that utilizes a new real-time animal tracking software for on-the-fly video analysis and closed-loop, external hardware communications to deliver stimuli based on specific behaviors in aquatic organisms, spanning three animal phyla: chordates (fish, frog), platyhelminthes (flatworm), and arthropods (crustacean). The system's open-source software features an intuitive graphical user interface and advanced adaptive threshold-based image segmentation for precise animal detection. We demonstrate the precision of animal tracking across multiple aquatic species with varying modes of locomotion. The presented technology interfaces easily with low-cost and open-source hardware such as the Arduino microcontroller family for closed-loop stimuli control. The new system has potential future applications in eco-neurotoxicology, where it could enable new opportunities for cognitive research in diverse small aquatic model organisms.
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Artrópodes , Software , Animais , Comportamento AnimalRESUMO
PURPOSE: It remains unclear whether time-to-surgery for distal radius fractures affects clinical, functional, or radiographic outcomes or health care costs/use. This systematic review investigated the outcomes of early versus delayed surgery for closed, isolated distal radius fractures in adult patients. METHODS: A comprehensive search of MEDLINE, Embase, and CINAHL databases was completed for all original case series, observational studies, and randomized controlled trials reporting clinical outcomes of both early and delayed surgically-treated distal radius fractures from database inception to July 01, 2022. A consistent threshold of two weeks was used to define early versus delayed treatment arms. RESULTS: Nine studies, including 16 intervention arms and 1,189 patients (858 early, 331 delayed), were included. Mean age was 58 years (range, 33-76). At more than one year, the frequency-weighted mean Disabilities of the Arm, Shoulder, and Hand score was 4 in the early group (n = 208; range, 1-17) and 21 in the delayed group (n = 181; range, 4-27). Range of motion, grip strength, and radiographic outcomes were comparable. The pooled mean complication rate (7% vs 5%) and revision rate (3.6% vs 1%) were very low in both groups. CONCLUSIONS: A delay in time-to-surgery greater than two weeks for distal radius fractures may be associated with inferior patient-reported outcomes. Early surgery was associated with improved long-term Disabilities of the Arm, Shoulder, and Hand scores. On the basis of the available evidence, range of motion, grip strength, and radiographic outcomes are similar. The complication and revision rates were very low in both groups and comparable. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.
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Fraturas do Rádio , Fraturas do Punho , Adulto , Humanos , Pessoa de Meia-Idade , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/cirurgia , Fixação de Fratura , Braço , Fixação Interna de Fraturas , Amplitude de Movimento Articular , Força da Mão , Resultado do Tratamento , Placas ÓsseasRESUMO
Many targeted natural product isolation approaches rely on the use of pre-existing bioactivity information to inform the strategy used for the isolation of new bioactive compounds. Bioactivity information can be available either in the form of prior assay data or via Structure Activity Relationship (SAR) information which can indicate a potential chemotype that exhibits a desired bioactivity. The work described herein utilizes a unique method of targeted isolation using structure-based virtual screening to identify potential antibacterial compounds active against MRSA within the marine sponge order Verongiida. This is coupled with molecular networking-guided, targeted isolation to provide a novel drug discovery procedure. A total of 12 previously reported bromotyrosine-derived alkaloids were isolated from the marine sponge species Pseudoceratina durissima, and the compound, (+)-aeroplysinin-1 (1) displayed activity against the MRSA pathogen (MIC: <32 µg/mL). The compounds (1−3, 6 and 9) were assessed for their central nervous system (CNS) interaction and behavioral toxicity to zebrafish (Danio rerio) larvae, whereby several of the compounds were shown to induce significant hyperactivity. Anthelmintic activity against the parasitic nematode Haemonchus contorutus was also evaluated (2−4, 6−8).
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Alcaloides , Anti-Helmínticos , Produtos Biológicos , Poríferos , Alcaloides/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Estrutura Molecular , Poríferos/química , Peixe-ZebraRESUMO
Due to increasing numbers of anthropogenic chemicals with unknown neurotoxic properties, there is an increasing need for a paradigm shift toward rapid and higher throughput behavioral bioassays. In this work, we demonstrate application of a purpose-built high throughput multidimensional behavioral test battery on larval stages of Danio rerio (zebrafish) at 5 days post fertilization (dpf). The automated battery comprised of the established spontaneous swimming (SS), simulated predator response (SPR), larval photomotor response (LPR) assays as well as a new thermotaxis (TX) assay. We applied the novel system to characterize environmentally relevant concentrations of emerging pharmaceutical micropollutants including anticonvulsants (gabapentin: 400 ng/L; carbamazepine: 3000 ng/L), inflammatory drugs (ibuprofen: 9800 ng/L), and antidepressants (fluoxetine: 300 ng/L; venlafaxine: 2200 ng/L). The successful integration of the thermal preference assay into a multidimensional behavioral test battery provided means to reveal ibuprofen-induced perturbations of thermal preference behaviors upon exposure during embryogenesis. Moreover, we discovered that photomotor responses in larval stages of fish are also altered by the as yet understudied anticonvulsant gabapentin. Collectively our results demonstrate the utility of high-throughput multidimensional behavioral ecotoxicity test batteries in prioritizing emerging risks associated with neuroactive drugs that can perturb neurodevelopment. Moreover, we showcase the added value of thermotaxis bioassays for preliminary screening of emerging contaminants.
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Poluentes Químicos da Água , Peixe-Zebra , Animais , Gabapentina/farmacologia , Ibuprofeno/farmacologia , Larva , Natação , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologiaRESUMO
Mucopolysaccharidosis IIIA (MPS IIIA, Sanfilippo syndrome type A), a paediatric neurological lysosomal storage disease, is caused by impaired function of the enzyme N-sulfoglucosamine sulfohydrolase (SGSH) resulting in impaired catabolism of heparan sulfate glycosaminoglycan (HS GAG) and its accumulation in tissues. MPS IIIA represents a significant proportion of childhood dementias. This condition generally leads to patient death in the teenage years, yet no effective therapy exists for MPS IIIA and a complete understanding of the mechanisms of MPS IIIA pathogenesis is lacking. Here, we employ targeted CRISPR/Cas9 mutagenesis to generate a model of MPS IIIA in the zebrafish, a model organism with strong genetic tractability and amenity for high-throughput screening. The sgshΔex5-6 zebrafish mutant exhibits a complete absence of Sgsh enzymatic activity, leading to progressive accumulation of HS degradation products with age. sgshΔex5-6 zebrafish faithfully recapitulate diverse CNS-specific features of MPS IIIA, including neuronal lysosomal overabundance, complex behavioural phenotypes, and profound, lifelong neuroinflammation. We further demonstrate that neuroinflammation in sgshΔex5-6 zebrafish is largely dependent on interleukin-1ß and can be attenuated via the pharmacological inhibition of Caspase-1, which partially rescues behavioural abnormalities in sgshΔex5-6 mutant larvae in a context-dependent manner. We expect the sgshΔex5-6 zebrafish mutant to be a valuable resource in gaining a better understanding of MPS IIIA pathobiology towards the development of timely and effective therapeutic interventions.
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Modelos Animais de Doenças , Hidrolases/genética , Mucopolissacaridose III , Animais , Humanos , Mucopolissacaridose III/metabolismo , Mucopolissacaridose III/patologia , Mutação , Fenótipo , Peixe-ZebraRESUMO
To further knowledge on cell wall composition in early land plants, we localized cell wall constituents in placental cells of the liverwort Marchantia polymorpha L. using monoclonal antibodies (MAbs) in the transmission electron microscope and histochemical staining. The placenta of M. polymorpha is similar to the majority of bryophytes in that both generations contain transfer cells with extensive wall ingrowths. Although the four major cell wall polymers, i.e., cellulose, pectins, hemicelluloses, and arabinogalactan proteins, are present, there are variations in the richness and specificity across generations. An abundance of homogalacturonan pectins in all placental cell walls is consistent with maintaining cell wall permeability and an acidic apoplastic pH necessary for solute transport. Although similar in ultrastructure, transfer cell walls on the sporophyte side in M. polymorpha are enriched with xyloglucans and diverse AGPs not detected on the gametophyte side of the placenta. Gametophyte wall ingrowths are more uniform in polymer composition. Lastly, extensins and callose are not components of transfer cell walls of M. polymorpha, which deviates from studies on transfer cells in other plants. The difference in polymer localizations in transfer cell walls between generations is consistent with directional movement from gametophyte to sporophyte in this liverwort.
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Parede Celular/química , Células Germinativas Vegetais/química , Marchantia/química , Parede Celular/ultraestrutura , Células Germinativas Vegetais/ultraestrutura , Microscopia Eletrônica de Transmissão , PolímerosRESUMO
Identifying novel marine-derived neuroactive chemicals with therapeutic potential is difficult due to inherent complexities of the central nervous system (CNS), our limited understanding of the molecular foundations of neuro-psychiatric conditions, as well as the limited applications of effective high-throughput screening models that recapitulate functionalities of the intact CNS. Furthermore, nearly all neuro-modulating chemicals exhibit poorly characterized pleiotropic activities often referred to as polypharmacology. The latter renders conventional target-based in vitro screening approaches very difficult to accomplish. In this context, chemobehavioural phenotyping using innovative small organism models such as planarians and zebrafish represent powerful and highly integrative approaches to study the impact of new chemicals on central and peripheral nervous systems. In contrast to in vitro bioassays aimed predominantly at identification of chemicals acting on single targets, phenotypic chemobehavioural analysis allows for complex multi-target interactions to occur in combination with studies of polypharmacological effects of chemicals in a context of functional and intact milieu of the whole organism. In this review, we will outline recent advances in high-throughput chemobehavioural phenotyping and provide a future outlook on how those innovative methods can be utilized for rapidly screening and characterizing marine-derived compounds with prospective applications in neuropharmacology and psychosomatic medicine.
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Organismos Aquáticos/química , Descoberta de Drogas , Psicotrópicos/química , Descoberta de Drogas/tendências , Avaliação Pré-Clínica de Medicamentos/tendências , Psicotrópicos/isolamento & purificaçãoRESUMO
Stearoyl-acyl carrier protein desaturase (SACPD-C) has been reported to control the accumulation of seed stearic acid; however, no study has previously reported its involvement in leaf stearic acid content and impact on leaf structure and morphology. A subset of an ethyl methanesulfonate mutagenized population of soybean (Glycine max) 'Forrest' was screened to identify mutants within the GmSACPD-C gene. Using a forward genetics approach, one nonsense and four missense Gmsacpd-c mutants were identified to have high levels of seed, nodule, and leaf stearic acid content. Homology modeling and in silico analysis of the GmSACPD-C enzyme revealed that most of these mutations were localized near or at conserved residues essential for diiron ion coordination. Soybeans carrying Gmsacpd-c mutations at conserved residues showed the highest stearic acid content, and these mutations were found to have deleterious effects on nodule development and function. Interestingly, mutations at nonconserved residues show an increase in stearic acid content yet retain healthy nodules. Thus, random mutagenesis and mutational analysis allows for the achievement of high seed stearic acid content with no associated negative agronomic characteristics. Additionally, expression analysis demonstrates that nodule leghemoglobin transcripts were significantly more abundant in soybeans with deleterious mutations at conserved residues of GmSACPD-C. Finally, we report that Gmsacpd-c mutations cause an increase in leaf stearic acid content and an alteration of leaf structure and morphology in addition to differences in nitrogen-fixing nodule structure.
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Glycine max/enzimologia , Oxigenases de Função Mista/metabolismo , Mutação/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Nódulos Radiculares de Plantas/metabolismo , Ácidos Esteáricos/metabolismo , Alelos , Sequência de Aminoácidos , Sequência de Bases , Sequência Conservada , Análise Mutacional de DNA , Regulação da Expressão Gênica de Plantas , Testes Genéticos , Leghemoglobina/metabolismo , Oxigenases de Função Mista/química , Oxigenases de Função Mista/genética , Modelos Moleculares , Folhas de Planta/anatomia & histologia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Sementes/metabolismo , Glycine max/genética , Homologia Estrutural de ProteínaRESUMO
Introduction: Leptoids, the food-conducting cells of polytrichaceous mosses, share key structural features with sieve elements in tracheophytes, including an elongated shape with oblique end walls containing modified plasmodesmata or pores. In tracheophytes, callose is instrumental in developing the pores in sieve elements that enable efficient photoassimilate transport. Aside from a few studies using aniline blue fluorescence that yielded confusing results, little is known about callose in moss leptoids. Methods: Callose location and abundance during the development of leptoid cell walls was investigated in the moss Polytrichum commune using aniline blue fluorescence and quantitative immunogold labeling (label density) in the transmission electron microscope. To evaluate changes during abiotic stress, callose abundance in leptoids of hydrated plants was compared to plants dried for 14 days under field conditions. A bioinformatic study to assess the evolution of callose within and across bryophytes was conducted using callose synthase (CalS) genes from 46 bryophytes (24 mosses, 15 liverworts, and 7 hornworts) and one representative each of five tracheophyte groups. Results: Callose abundance increases around plasmodesmata from meristematic cells to end walls in mature leptoids. Controlled drying resulted in a significant increase in label density around plasmodesmata and pores over counts in hydrated plants. Phylogenetic analysis of the CalS protein family recovered main clades (A, B, and C). Different from tracheophytes, where the greatest diversity of homologs is found in clade A, the majority of gene duplication in bryophytes is in clade B. Discussion: This work identifies callose as a crucial cell wall polymer around plasmodesmata from their inception to functioning in leptoids, and during water stress similar to sieve elements of tracheophytes. Among bryophytes, mosses exhibit the greatest number of multiple duplication events, while only two duplications are revealed in hornwort and none in liverworts. The absence in bryophytes of the CalS 7 gene that is essential for sieve pore development in angiosperms, reveals that a different gene is responsible for synthesizing the callose associated with leptoids in mosses.
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Chemobehavioural phenotyping presents unique opportunities for analyzing neurotoxicants and discovering behavior-modifying neuroceuticals in small aquatic model organisms such as zebrafish (Danio rerio). A recently popularized approach in this field involves the utilization of zebrafish embryos for a photo-motor response (PMR) bioassay. The PMR bioassay entails stimulating zebrafish embryos between 24 and 36 h post fertilization (hpf) with a high-intensity light stimulus, inducing a transient increase in the frequency of photo-induced embryo body flexions. These flexions can be computationally analyzed to derive behavioral signatures, enabling the categorization of neuromodulating chemicals. Despite the significant advantages of the PMR bioassay, its widespread implementation is hindered by lack of well described and straightforward high-throughput bioinformatic analysis of behavioral data. In this methods article, we present an easily implementable bioinformatics protocol specifically designed for rapid behavioral analysis of large cohorts of zebrafish specimens in PMR bioassays. We also address common pitfalls encountered during PMR analysis, discuss its limitations, and propose future directions for developing next-generation biometric analysis techniques in chemobehavioural assays utilizing zebrafish embryos.
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Síndromes Neurotóxicas , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Embrião não MamíferoRESUMO
Assessment of animals' sensory-motor functions requires precise and electronically controlled stimuli to induce and quantify specific behavioral phenotypes. However, accessible and inexpensive tools for conducting diverse sensory-motor biotests with fish are lacking. In this work, we present an open-source software and hardware interface that enables automated delivery of three independent and fully programmable stimuli for behavioral bioassays. We demonstrate the proof-of-concept application of this low-cost technology in establishing reproducible fear responses using a mechanical tap-startle stimulus in larval zebrafish. This response is characterized by a sudden burst of motion in response to a nondirectional mechanical stimulus delivered to the fish chamber. We propose that the simplicity and flexibility of this interface offer innovative opportunities for studying sensory-motor functions in various fields, including neurobiology, neuropharmacology, neurotoxicology, and aquatic ecotoxicology.
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Perciformes , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Comportamento Animal/fisiologia , Larva/fisiologia , SoftwareRESUMO
Longitudinal monitoring of patients with advanced cancers is crucial to evaluate both disease burden and treatment response. Current liquid biopsy approaches mostly rely on the detection of DNA-based biomarkers. However, plasma RNA analysis can unleash tremendous opportunities for tumor state interrogation and molecular subtyping. Through the application of deep learning algorithms to the deconvolved transcriptomes of RNA within plasma extracellular vesicles (evRNA), we successfully predicted consensus molecular subtypes in patients with metastatic colorectal cancer. Analysis of plasma evRNA also enabled monitoring of changes in transcriptomic subtype under treatment selection pressure and identification of molecular pathways associated with recurrence. This approach also revealed expressed gene fusions and neoepitopes from evRNA. These results demonstrate the feasibility of using transcriptomic-based liquid biopsy platforms for precision oncology approaches, spanning from the longitudinal monitoring of tumor subtype changes to the identification of expressed fusions and neoantigens as cancer-specific therapeutic targets, sans the need for tissue-based sampling. SIGNIFICANCE: The development of an approach to interrogate molecular subtypes, cancer-associated pathways, and differentially expressed genes through RNA sequencing of plasma extracellular vesicles lays the foundation for liquid biopsy-based longitudinal monitoring of patient tumor transcriptomes.
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Biomarcadores Tumorais , Vesículas Extracelulares , Perfilação da Expressão Gênica , Transcriptoma , Humanos , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Perfilação da Expressão Gênica/métodos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/sangue , Biópsia Líquida/métodos , Neoplasias Colorretais/genética , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , Neoplasias/sangue , Neoplasias/patologiaRESUMO
Recent research has found that individuals often vary in how consistently they express their behavior over time (i.e., behavioral predictability) and suggested that these individual differences may be heritable. However, little is known about the intrinsic factors that drive variation in the predictability of behavior. Indeed, whether variation in behavioral predictability is sex-specific is not clear. This is important, as behavioral predictability has been associated with vulnerability to predation, suggesting that the predictability of behavioral traits may have key fitness implications. We investigated whether male and female eastern mosquitofish (Gambusia holbrooki) differed in the predictability of their risk-taking behavior. Specifically, over a total of 954 behavioral trials, we repeatedly measured risk-taking behavior with three commonly used assays-refuge-use, thigmotaxis, and foraging latency. We predicted that there would be consistent sex differences in both mean-level risk-taking behavior and behavioral predictability across the assays. We found that risk-taking behavior was repeatable within each assay, and that some individuals were consistently bolder than others across all three assays. There were also consistent sex differences in mean-level risk-taking behavior, with males being bolder across all three assays compared to females. In contrast, both the magnitude and direction of sex differences in behavioral predictability were assay-specific. Taken together, these results highlight that behavioral predictability may be independent from underlying mean-level behavioral traits and suggest that males and females may differentially adjust the consistency of their risk-taking behavior in response to subtle changes in environmental conditions.
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PURPOSE: In metastatic colorectal cancer, the detection of RAS mutations by circulating tumor DNA (ctDNA) has emerged as a valid and noninvasive alternative approach to determining RAS status. However, some RAS mutations may be missed, that is, false negatives can occur, possibly compromising important treatment decisions. We propose a statistical model to assess the probability of false negatives when performing ctDNA testing for RAS. METHODS: Cohorts of 172 subjects with tissue and multipanel ctDNA testing from MD Anderson Cancer Center and 146 subjects from Massachusetts General Hospital were collected. We developed a Bayesian model that uses observed frequencies of reference mutations (the maximum of APC and TP53) to provide information about the probability of KRAS false negatives. The model was alternatively trained on one cohort and tested on the other. All data were collected on Guardant assays. RESULTS: The model suggests that negative KRAS findings are believable when the maximum of APC and TP53 frequencies is at least 8% (corresponding posterior probability of false negative <5%). Validation studies demonstrated the ability of our tool to discriminate between false-negative and true-negative subjects. Simulations further confirmed the utility of the proposed approach. CONCLUSION: We suggest clinicians use the tool to more precisely quantify KRAS false-negative ctDNA results when at least one of the reference mutations (APC, TP53) is observed; usage may be especially important for subjects with a maximum reference frequency of <8%. Extension of the methodology to predict false negatives of other genes is possible. Additional reference genes can also be considered. Use of personal training data sets is supported. An open-source R Shiny application is available for public use.
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DNA Tumoral Circulante , Neoplasias do Colo , Humanos , DNA Tumoral Circulante/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Teorema de Bayes , Mutação/genéticaRESUMO
Previous studies implicated protein arginine methyltransferase 5 (PRMT5) as a synthetic lethal target for MTAP-deleted (MTAP del) cancers; however, the pharmacologic characterization of small-molecule inhibitors that recapitulate the synthetic lethal phenotype has not been described. MRTX1719 selectively inhibited PRMT5 in the presence of MTA, which is elevated in MTAP del cancers, and inhibited PRMT5-dependent activity and cell viability with >70-fold selecti-vity in HCT116 MTAP del compared with HCT116 MTAP wild-type (WT) cells. MRTX1719 demonstrated dose-dependent antitumor activity and inhibition of PRMT5-dependent SDMA modification in MTAP del tumors. In contrast, MRTX1719 demonstrated minimal effects on SDMA and viability in MTAP WT tumor xenografts or hematopoietic cells. MRTX1719 demonstrated marked antitumor activity across a panel of xenograft models at well-tolerated doses. Early signs of clinical activity were observed including objective responses in patients with MTAP del melanoma, gallbladder adenocarcinoma, mesothelioma, non-small cell lung cancer, and malignant peripheral nerve sheath tumors from the phase I/II study. SIGNIFICANCE: PRMT5 was identified as a synthetic lethal target for MTAP del cancers; however, previous PRMT5 inhibitors do not selectively target this genotype. The differentiated binding mode of MRTX1719 leverages the elevated MTA in MTAP del cancers and represents a promising therapy for the â¼10% of patients with cancer with this biomarker. See related commentary by Mulvaney, p. 2310. This article is featured in Selected Articles from This Issue, p. 2293.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Linhagem Celular Tumoral , Mutações Sintéticas Letais , Inibidores Enzimáticos/farmacologia , Proteína-Arginina N-MetiltransferasesRESUMO
Analysis of sensorimotor behavioral responses to stimuli such as light can provide an enhanced relevance during rapid prioritisation of chemical risk. Due to technical limitations, there have been, however, only minimal studies on using invertebrate phototactic behaviors in aquatic ecotoxicity testing. In this work, we demonstrate an innovative, purpose-built analytical system for a high-throughput phototactic biotest with nauplii of euryhaline brine shrimp Artemia franciscana. We also, for the first time, present a novel and dedicated bioinformatic approach that facilitates high-throughput analysis of phototactic behaviors at scale with great fidelity. The nauplii exhibited consistent light-seeking behaviors upon extinguishing a brief programmable light stimulus (5500K, 400 lux) without habituation. A proof-of-concept validation involving the short-term exposure of eggs (24 h) and instar I larval stages (6 h) to sub-lethal concentrations of insecticides organophosphate chlorpyrifos (10 µg/L) and neonicotinoid imidacloprid (50 µg/L) showed perturbation in light seeking behaviors in the absence of or minimal alteration in general mobility. Our preliminary data further support the notion that phototactic bioassays can represent an attractive new avenue in behavioral ecotoxicology because of their potential sensitivity, responsiveness, and low cost.
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Behavioral phenotypic analysis is an emerging and increasingly important toolbox in aquatic ecotoxicology. In this regard digital video recording has recently become a standard in obtaining behavioral data. Subsequent analysis requires applications of specialized software for detecting and reconstructing animal locomotory trajectories as well as extracting quantitative biometric endpoints associated with specific behavioral traits. Despite some profound advantages for behavioral ecotoxicology, there is a notable lack of standardization of procedures and guidelines that would aid in consistently acquiring high-quality digital videos. The latter are fundamental for using animal tracking software successfully and to avoid issues such as identification switching, incorrect interpolation, and low tracking visibility. Achieving an optimized tracking not only saves user time and effort to analyze the results but also provides high-fidelity data with minimal artifacts. In the present study we, for the first time, provide an easily accessible guide on how to set up and optimize digital video acquisition while minimizing pitfalls in obtaining the highest-quality data for subsequent animal tracking. We also discuss straightforward digital video postprocessing techniques that can be employed to further enhance tracking consistency or improve the videos that were acquired in otherwise suboptimal settings. The present study provides an essential guidebook for any aquatic ecotoxicology studies that utilize digital video acquisition systems for evaluation of behavioral endpoints. Environ Toxicol Chem 2022;41:2342-2352. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
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Ecotoxicologia , Software , Animais , Comportamento AnimalRESUMO
Contamination of the environment by pharmaceutical pollutants poses an increasingly critical threat to aquatic ecosystems around the world. This is particularly true of psychoactive compounds, such as antidepressant drugs, which have become ubiquitous contaminants and have been demonstrated to modify aquatic animal behaviours at very low concentrations (i.e. ng/L). Despite raising risks to the hydrosphere, there is a notable paucity of data on the long term, multigenerational effects of antidepressants at environmentally realistic concentrations. Moreover, current research has predominantly focused on mean-level effects, with little research on variation among and within individuals when considering key behavioural traits. In this work, we used a multigenerational exposure of a freshwater snail (Physa acuta) to an environmentally relevant concentration of the antidepressant fluoxetine (mean measured concentration: 32.7 ng/L, SE: 2.3). The snails were allowed to breed freely in large mesocosm populations over 3 years. Upon completion of the exposure, we repeatedly measured the locomotory activity (624 measures total), reproductive output (234 measures total) as well as morphometric endpoints (78 measures total). While we found no mean-level differences between treatments in locomotory activities, we did find that fluoxetine exposed snails (n = 46) had significantly reduced behavioural plasticity (i.e. VW; within-individual variation) in activity levels compared to unexposed snails (n = 32). As a result, fluoxetine exposed snails demonstrated significant behavioural repeatability, which was not the case for unexposed snails. Further, we report a reduction in egg mass production in fluoxetine exposed snails, and a marginally non-significant difference in morphology between treatment groups. These results highlight the potential detrimental effects of long-term fluoxetine exposure on non-target organisms at environmentally realistic dosages. Additionally, our findings demonstrate the underappreciated potential for psychoactive contaminants to have impacts beyond mean-level effects, with consequences for population resilience to current and future environmental challenges.