RESUMO
The MYCN oncoprotein binds active promoters in a heterodimer with its partner protein MAX. MYCN also interacts with the nuclear exosome, a 3'-5' exoribonuclease complex, suggesting a function in RNA metabolism. Here, we show that MYCN forms stable high-molecular-weight complexes with the exosome and multiple RNA-binding proteins. MYCN binds RNA in vitro and in cells via a conserved sequence termed MYCBoxI. In cells, MYCN associates with thousands of intronic transcripts together with the ZCCHC8 subunit of the nuclear exosome targeting complex and enhances their processing. Perturbing exosome function results in global re-localization of MYCN from promoters to intronic RNAs. On chromatin, MYCN is then replaced by the MNT(MXD6) repressor protein, inhibiting MYCN-dependent transcription. RNA-binding-deficient alleles show that RNA-binding limits MYCN's ability to activate cell growth-related genes but is required for MYCN's ability to promote progression through S phase and enhance the stress resilience of neuroblastoma cells.
Assuntos
Proteína Proto-Oncogênica N-Myc , Proteínas Nucleares , Proteínas Oncogênicas , Proteínas de Ligação a RNA , Proteína Proto-Oncogênica N-Myc/metabolismo , Proteína Proto-Oncogênica N-Myc/genética , Humanos , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Proteínas Oncogênicas/metabolismo , Proteínas Oncogênicas/genética , Regiões Promotoras Genéticas , Linhagem Celular Tumoral , Neuroblastoma/metabolismo , Neuroblastoma/genética , Neuroblastoma/patologia , Exossomos/metabolismo , Exossomos/genética , Íntrons , Ligação Proteica , Núcleo Celular/metabolismo , Complexo Multienzimático de Ribonucleases do Exossomo/metabolismo , Complexo Multienzimático de Ribonucleases do Exossomo/genética , Regulação Neoplásica da Expressão Gênica , RNA/metabolismo , RNA/genética , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Proliferação de CélulasRESUMO
Imiquimod is a small-molecule ligand of Toll-like receptor-7 (TLR7) that is licensed for the treatment of viral infections and cancers of the skin. Imiquimod has TLR7-independent activities that are mechanistically unexplained, including NLRP3 inflammasome activation in myeloid cells and apoptosis induction in cancer cells. We investigated the mechanism of inflammasome activation by imiquimod and the related molecule CL097 and determined that K+ efflux was dispensable for NLRP3 activation by these compounds. Imiquimod and CL097 inhibited the quinone oxidoreductases NQO2 and mitochondrial Complex I. This induced a burst of reactive oxygen species (ROS) and thiol oxidation, and led to NLRP3 activation via NEK7, a recently identified component of this inflammasome. Metabolic consequences of Complex I inhibition and endolysosomal effects of imiquimod might also contribute to NLRP3 activation. Our results reveal a K+ efflux-independent mechanism for NLRP3 activation and identify targets of imiquimod that might be clinically relevant.
Assuntos
Inflamassomos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Potássio/metabolismo , RNA Nuclear Pequeno/farmacologia , Animais , Complexo I de Transporte de Elétrons/metabolismo , Camundongos , Quinases Relacionadas a NIMA/metabolismo , Quinona Redutases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptor 7 Toll-Like/metabolismoRESUMO
OBJECTIVE: The hallmark oncogene MYC drives the progression of most tumours, but direct inhibition of MYC by a small-molecule drug has not reached clinical testing. MYC is a transcription factor that depends on several binding partners to function. We therefore explored the possibility of targeting MYC via its interactome in pancreatic ductal adenocarcinoma (PDAC). DESIGN: To identify the most suitable targets among all MYC binding partners, we constructed a targeted shRNA library and performed screens in cultured PDAC cells and tumours in mice. RESULTS: Unexpectedly, many MYC binding partners were found to be important for cultured PDAC cells but dispensable in vivo. However, some were also essential for tumours in their natural environment and, among these, the ATPases RUVBL1 and RUVBL2 ranked first. Degradation of RUVBL1 by the auxin-degron system led to the arrest of cultured PDAC cells but not untransformed cells and to complete tumour regression in mice, which was preceded by immune cell infiltration. Mechanistically, RUVBL1 was required for MYC to establish oncogenic and immunoevasive gene expression identifying the RUVBL1/2 complex as a druggable vulnerability in MYC-driven cancer. CONCLUSION: One implication of our study is that PDAC cell dependencies are strongly influenced by the environment, so genetic screens should be performed in vitro and in vivo. Moreover, the auxin-degron system can be applied in a PDAC model, allowing target validation in living mice. Finally, by revealing the nuclear functions of the RUVBL1/2 complex, our study presents a pharmaceutical strategy to render pancreatic cancers potentially susceptible to immunotherapy.
Assuntos
ATPases Associadas a Diversas Atividades Celulares , Carcinoma Ductal Pancreático , DNA Helicases , Neoplasias Pancreáticas , Proteínas Proto-Oncogênicas c-myc , Animais , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , ATPases Associadas a Diversas Atividades Celulares/metabolismo , ATPases Associadas a Diversas Atividades Celulares/genética , Camundongos , Humanos , DNA Helicases/genética , DNA Helicases/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Linhagem Celular Tumoral , Proteínas de Transporte/metabolismo , Proteínas de Transporte/genéticaRESUMO
Generalist plant-feeding insects are characterised by a broad host repertoire that can comprise several families or even different orders of plants. The genetic and physiological mechanisms underlying the use of such a wide host range are still not fully understood. Earlier studies indicate that the consumption of different host plants is associated with host-specific gene expression profiles. It remained, however, unclear if and how larvae can alter these profiles in the case of a changing host environment. Using the polyphagous comma butterfly (Polygonia c-album) we show that larvae can adjust their transcriptional profiles in response to a new host plant. The switch to some of the host plants, however, resulted in a larger transcriptional response and, thus, seems to be more challenging. At a physiological level, no correspondence for these patterns could be found in larval performance. This suggests that a high transcriptional but also phenotypic flexibility are essential for the use of a broad and diverse host range. We furthermore propose that host switch tests in the laboratory followed by transcriptomic investigations can be a valuable tool to examine not only plasticity in host use but also subtle and/or transient trade-offs in the evolution of host plant repertoires.
Assuntos
Borboletas , Larva , Transcriptoma , Borboletas/genética , Animais , Larva/genética , Herbivoria , Plantas/genética , Especificidade de Hospedeiro/genéticaRESUMO
The analysis of real-world data (RWD) has become increasingly important in health research in recent years. With the BfArM Health Data Lab (HDL), which is currently being set up, researchers will in future be able to gain access to routine data from the statutory health insurance of around 74 million people in Germany. Data from electronic patient records can also be made available for research prospectively. In doing so, the Health Data Lab guarantees the highest data protection and IT security standards. The digital application process, the provision of data in secure processing environments as well as the features supporting the analyses such as catalogues of coding systems, a point-and-click analysis tool and predefined standard analyses increase user-friendliness for researchers. The use of the extensive health data accessible at HDL will open a wide range of future possibilities for improving the health system and the quality of care. This article begins by highlighting the advantages of the HDL and outlining the opportunities that the RWD offers for research in healthcare and for the population. The structure and central aspects of the HDL are explained afterwards. An outlook on the opportunities of linking different data is given. What the application and data usage processes at the HDL will look like is illustrated using the example of fictitious possibilities for analysing long COVID based on the routine data available at the HDL in the future.
Assuntos
Atenção à Saúde , Síndrome de COVID-19 Pós-Aguda , Humanos , Alemanha , Registros Eletrônicos de SaúdeRESUMO
INTRODUCTION: Preclinical, epidemiological, and small clinical studies suggest that green tea extract (GTE) and its major active component epigallocatechingallate (EGCG) exhibit antineoplastic effects in the colorectum. METHODS: A randomized, double-blind trial of GTE standardized to 150 mg of EGCG b.i.d. vs placebo over 3 years was conducted to prevent colorectal adenomas (n = 1,001 with colon adenomas enrolled, 40 German centers). Randomization (1:1, n = 879) was performed after a 4-week run-in with GTE for safety assessment. The primary end point was the presence of adenoma/colorectal cancer at the follow-up colonoscopy 3 years after randomization. RESULTS: The safety profile of GTE was favorable with no major differences in adverse events between the 2 well-balanced groups. Adenoma rate in the modified intention-to-treat set (all randomized participants [intention-to-treat population] and a follow-up colonoscopy 26-44 months after randomization; n = 632) was 55.7% in the placebo and 51.1% in the GTE groups. This 4.6% difference was not statistically significant (adjusted relative risk 0.905; P = 0.1613). The respective figures for the per-protocol population were 54.3% (151/278) in the placebo group and 48.3% (129/267) in the GTE group, indicating a slightly lower adenoma rate in the GTE group, which was not significant (adjusted relative risk 0.883; P = 0.1169). DISCUSSION: GTE was well tolerated, but there was no statistically significant difference in the adenoma rate between the GTE and the placebo groups in the whole study population.
Assuntos
Adenoma , Neoplasias Colorretais , Adenoma/prevenção & controle , Antioxidantes/uso terapêutico , Neoplasias Colorretais/prevenção & controle , Método Duplo-Cego , Humanos , Extratos Vegetais/uso terapêutico , CháRESUMO
Bupropion is hydroxylated to its primary active metabolite hydroxybupropion by cytochrome P450 enzyme CYP2B6. In vitro data suggest the existence of alternative hydroxylation pathways mediated by the highly polymorphic enzyme CYP2C19. However, the impact of its genetic variants on bupropion metabolism in vivo is still under investigation. We report the case of a 28-year-old male Caucasian outpatient suffering from major depressive disorder who did not respond to a treatment with bupropion. Therapeutic drug monitoring revealed very low serum concentrations of both bupropion and hydroxybupropion. Genotyping identified a heterozygous status for the gain-of-function allele with the genotype CYP2C19*1/*17 predicting enhanced enzymatic activity. The present case shows a reduced bupropion efficacy, which may be explained by a reduced active moiety of bupropion and its active metabolite hydroxybupropion, due to alternative hydroxylation pathways mediated by CYP2C19 in an individual with CYP2C19 rapid metabolizer status. The case report thus illustrates the clinical relevance of therapeutic drug monitoring in combination with pharmacogenetics diagnostics for a personalized treatment approach.
Assuntos
Antidepressivos de Segunda Geração/sangue , Bupropiona/análogos & derivados , Bupropiona/sangue , Citocromo P-450 CYP2C19/genética , Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/genética , Adulto , Antidepressivos de Segunda Geração/uso terapêutico , Bupropiona/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Humanos , MasculinoRESUMO
Processing of and responding to various signals is an essential cellular function that influences survival, homeostasis, development, and cell death. Extra- or intracellular signals are perceived via specific receptors and transduced in a particular signalling pathway that results in a precise response. Reversible post-translational redox modifications of cysteinyl and methionyl residues have been characterised in countless signal transduction pathways. Due to the low reactivity of most sulfur-containing amino acid side chains with hydrogen peroxide, for instance, and also to ensure specificity, redox signalling requires catalysis, just like phosphorylation signalling requires kinases and phosphatases. While reducing enzymes of both cysteinyl- and methionyl-derivates have been characterised in great detail before, the discovery and characterisation of MICAL proteins evinced the first examples of specific oxidases in signal transduction. This article provides an overview of the functions of MICAL proteins in the redox regulation of cellular functions.
Assuntos
Proteínas dos Microfilamentos/fisiologia , Oxigenases de Função Mista/fisiologia , Oxirredução , Transdução de Sinais , Animais , Catálise , Cisteína/química , Proteínas do Citoesqueleto/metabolismo , Genoma , Humanos , Peróxido de Hidrogênio/química , Cinética , Oxirredutases/metabolismo , Oxigênio/metabolismo , Fosforilação , Ligação ProteicaRESUMO
PURPOSE: Adverse drug reactions (ADR) account for 5 to 7% of emergency department (ED) consultations. We aimed to assess medication risk profiles for ADRs leading to ED visits. METHODS: We analysed medication intake and patient demographics in a prospective multi-centre observational study collecting ADR cases in four large EDs in Germany. Odds ratios (OR) were calculated to relate drug classes taken to those suspicious for an ADR after a causality assessment. RESULTS: A total of 2215 cases of ED visits due to ADRs were collected. The median age of the cohort was 73 years; in median, six co-morbidities and an intake of seven drugs were documented. Antineoplastic/immunomodulating agents had the highest OR for being suspected for an ADR (OR 20.45, 95% CI 14.54-28.77), followed by antithrombotics (OR 2.94, 95% CI 2.49-3.47), antibiotics (OR 2.65, 95% CI 1.78-3.95), systemic glucocorticoids (OR 2.43, 95% CI 1.54-3.82) and drugs affecting the central nervous system (CNS), such as antipsychotics (OR 2.36, 95% CI 1.46-3.81), antidepressants (OR 2.10, 95% CI 1.57-2.83), antiparkinsonian medication (OR 2.11, 95% CI 1.15-3.84), opioids (OR 1.79, 95% CI 1.26-2.54) and non-opioid analgesics (OR 1.32, 95% CI 1.01-1.72). CONCLUSIONS: Patients experiencing ADRs leading to ED visits are commonly old, multi-morbid and multi-medicated. CNS drugs may be more relevant than prior expected. With calculating ORs, we could replicate involvement of antineoplastic agents, antithrombotics, antibiotics, systemic glucocorticoids and non-opioid analgesics as frequently suspected for ADRs in EDs. TRIAL REGISTRATION: DRKS-ID: DRKS00008979.
Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Alemanha , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
BACKGROUND: Bavaria, a large federal state in Germany, has been declared free from infections with Bovine Alphaherpesvirus 1 (BoHV-1) in 2011. To maintain this status the cattle population is monitored for antibodies against BoHV-1 regularly. Several years ago, infrequent but recurrent problems in this sero-surveillance were statistically put into correlation with the presence of antibodies against Bovine Alphaherpesvirus 2 (BoHV-2). In Europe, BoHV-2 is primarily known as the agent causing bovine herpes mammillitis. However, very little information about BoHV-2 infections in Bavaria is available so far. Therefore, the aims of this study were to determine BoHV-2 seroprevalences and to detect virus genomes in potential clinical samples. RESULTS: 6801 blood sera of healthy cattle from all over Bavaria were tested for antibodies against BoHV-2, revealing an overall seroprevalence of 5.51%. Interestingly, seroprevalences markedly varied between the North and the South of Bavaria, namely from 0.42 to 11.17%. Concurrently, the previously reported relation between the epidemiologically inexplicable sero-reactivities in BoHV-1 ELISAs and the presence of BoHV-2 infections were statistically corroborated in this study. To detect BoHV-2 genomes a fast and sensitive real time PCR was established. Using a multiple PCR strategy, tissue samples from skin lesions at relevant localizations, corresponding lymph nodes, and trigeminal ganglia from 111 animals, as well as nasal swabs from 918 bovines with respiratory symptoms were tested. However, BoHV-2 genomes were not detected in any of these samples. CONCLUSIONS: BoHV-2 antibodies were found in samples from bovines all over Bavaria, albeit with an explicit South-North-divide. BoHV-2 genomes, however, could not be detected in any of the analyzed samples, indicating that acute clinical cases as well as obvious virus reactivation are relatively rare. Consequently, the future spread of BoHV-2 infections throughout Bavaria, particularly, after eradicating BoHV-1, has to be further monitored.
Assuntos
Doenças dos Bovinos/virologia , Infecções por Herpesviridae/veterinária , Herpesvirus Bovino 2/isolamento & purificação , Animais , Anticorpos Antivirais/análise , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Alemanha , Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/imunologia , Herpesvirus Bovino 2/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Estudos SoroepidemiológicosRESUMO
INTRODUCTION: Due to a continuing increase of bacterial resistance in common uropathogens, we wanted to revisit our standards for the diagnosis and treatment of lower urinary tract infections, in the setting of urological outpatient care in a conurbation in Germany. PATIENTS AND METHODS: All subjects presenting with significant bacteriuria at our urology clinics in Mülheim, Germany, in 2011 were included. Comorbidity, bacterial species, urinary tract symptoms, and empirically prescribed antibiotics were taken from the patients' records. RESULTS: In 2011, a total of 1,324 patients were included (793 female, 531 male). Of the 771 patients with symptomatic bacteriuria, 647 received antibiotic treatment, as well as 116 of 409 patients with asymptomatic bacteriuria. Escherichia coli was identified in 60% of the included patients. In 427 E. coli infections, bacterial resistance was found in 14% of 316 cases treated with quinolone, in 21% of 53 cases treated with co-trimoxazole, and in only 3% of 58 cases treated with nitrofurantoin. CONCLUSIONS: We found a high use of fluoroquinolones for empirical first-line antibiotics in the treatment of lower urinary tract infections. In our regional setting, antibiotic stewardship needs to be promoted, along national and international guidelines, to avoid unnecessary prescription of fluoroquinolones for empirical treatment.
Assuntos
Antibacterianos/uso terapêutico , Infecções Urinárias/diagnóstico , Infecções Urinárias/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Assistência Ambulatorial , Farmacorresistência Bacteriana , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
F-BAR proteins are prime candidates to regulate membrane curvature and dynamics during different developmental processes. Here, we analyzed nostrin, a so-far-unknown Drosophila melanogaster F-BAR protein related to Cip4. Genetic analyses revealed a strong synergism between nostrin and cip4 functions.Whereas single mutant flies are viable and fertile, combined loss of nostrin and cip4 results in reduced viability and fertility. Double mutant escaper flies show enhanced wing polarization defects and females exhibit strong egg chamber encapsulation defects. Live imaging analysis suggests that the observed phenotypes are caused by an impaired turnover of E-cadherin at the membrane. Simultaneous knockdown of Cip4 and Nostrin strongly increases the formation of tubular E-cadherin vesicles at adherens junctions. Cip4 and Nostrin localize at distinct membrane subdomains. Both proteins prefer similar membrane curvatures but seem to form distinct membrane coats and do not heterooligomerize. Our data suggest an important synergistic function of both F-BAR proteins in membrane dynamics. We propose a cooperative recruitment model, in which Cip4 initially promotes membrane invagination and early-actin-based endosomal motility, and Nostrin makes contacts with microtubules through the kinesin Khc-73 for trafficking of recycling endosomes.
Assuntos
Caderinas/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Óvulo/fisiologia , Asas de Animais/embriologia , Junções Aderentes/metabolismo , Animais , Proteínas de Transporte/genética , Diferenciação Celular , Linhagem Celular , Proteínas de Drosophila/genética , Drosophila melanogaster/embriologia , Drosophila melanogaster/genética , Endocitose/genética , Endocitose/fisiologia , Endossomos/metabolismo , Células Epiteliais/citologia , Cinesinas/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Morfogênese/fisiologia , Transporte Proteico/fisiologia , Interferência de RNA , RNA Interferente PequenoRESUMO
BACKGROUND: Multiple sclerosis (MS) patients are at risk of renewed disease activity after discontinuing natalizumab (NAT) treatment. OBJECTIVE: Assessing the implication of T helper 17 (Th17) cells in MS reactivation after NAT cessation. METHODS: We monitored frequencies of Th17 cells and interleukin (IL)-17 cytokine levels in blood samples of 57 MS patients, without, during, and after NAT exposure. RESULTS: Frequencies of both Th17 cells and, in part, also IL-17 levels, in peripheral blood increased under prolonged NAT therapy, returned to baseline after NAT withdrawal and became almost undetectable in blood samples of individuals who experienced relapses during the wash-out phase. CONCLUSION: Assessing the Th17-cell/IL-17 axis might help to predict rebound MS activity after NAT withdrawal.
Assuntos
Esclerose Múltipla/diagnóstico , Esclerose Múltipla/tratamento farmacológico , Natalizumab/farmacologia , Células Th17/citologia , Adulto , Feminino , Humanos , Interleucina-17/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Células Th17/efeitos dos fármacos , Adulto JovemRESUMO
We describe the design, fabrication, and characterization of a one-dimensional silicon photonic crystal cavity in which a central slot is used to enhance the overlap between highly localized optical and mechanical modes. The optical mode has an extremely small mode volume of 0.017(λvacâ/ân)3, and an optomechanical vacuum coupling rate of 310 kHz is measured for a mechanical mode at 2.69 GHz. With optical quality factors up to 1.2 × 105, fabricated devices are in the resolved-sideband regime. The electric field has its maximum at the slot wall and couples to the in-plane breathing motion of the slot. The optomechanical coupling is thus dominated by the moving-boundary effect, which we simulate to be six times greater than the photoelastic effect, in contrast to most structures, where the photoelastic effect is often the primary coupling mechanism.
RESUMO
An all-optical transistor is a device in which a gate light pulse switches the transmission of a target light pulse with a gain above unity. The gain quantifies the change of the transmitted target photon number per incoming gate photon. We study the quantum limit of one incoming gate photon and observe a gain of 20. The gate pulse is stored as a Rydberg excitation in an ultracold gas. The transmission of the subsequent target pulse is suppressed by Rydberg blockade, which is enhanced by a Förster resonance. The detected target photons reveal in a single shot with a fidelity above 0.86 whether a Rydberg excitation was created during the gate pulse. The gain offers the possibility to distribute the transistor output to the inputs of many transistors, thus making complex computational tasks possible.
Assuntos
Anorexia Nervosa/fisiopatologia , Encéfalo/fisiopatologia , Medo/fisiologia , Anorexia Nervosa/complicações , Ansiedade/complicações , Ansiedade/fisiopatologia , Mapeamento Encefálico , Ingestão de Alimentos , Feminino , Resposta Galvânica da Pele , Humanos , Imageamento por Ressonância Magnética , Vias NeuraisRESUMO
The OECD validation study of the zebrafish embryo acute toxicity test (ZFET) for acute aquatic toxicity testing evaluated the ZFET reproducibility by testing 20 chemicals at 5 different concentrations in 3 independent runs in at least 3 laboratories. Stock solutions and test concentrations were analytically confirmed for 11 chemicals. Newly fertilised zebrafish eggs (20/concentration and control) were exposed for 96h to chemicals. Four apical endpoints were recorded daily as indicators of acute lethality: coagulation of the embryo, lack of somite formation, non-detachment of the tail bud from the yolk sac and lack of heartbeat. Results (LC50 values for 48/96h exposure) show that the ZFET is a robust method with a good intra- and inter-laboratory reproducibility (CV<30%) for most chemicals and laboratories. The reproducibility was lower (CV>30%) for some very toxic or volatile chemicals, and chemicals tested close to their limit of solubility. The ZFET is now available as OECD Test Guideline 236. Considering the high predictive capacity of the ZFET demonstrated by Belanger et al. (2013) in their retrospective analysis of acute fish toxicity and fish embryo acute toxicity data, the ZFET is ready to be considered for acute fish toxicity for regulatory purposes.
Assuntos
Testes de Toxicidade Aguda/métodos , Poluentes Químicos da Água/toxicidade , Animais , Laboratórios , Dose Letal Mediana , Organização para a Cooperação e Desenvolvimento Econômico , Reprodutibilidade dos Testes , Peixe-ZebraRESUMO
Speech is a promising biomarker for schizophrenia spectrum disorder (SSD) and major depressive disorder (MDD). This proof of principle study investigates previously studied speech acoustics in combination with a novel application of voice pathology features as objective and reproducible classifiers for depression, schizophrenia, and healthy controls (HC). Speech and voice features for classification were calculated from recordings of picture descriptions from 240 speech samples (20 participants with SSD, 20 with MDD, and 20 HC each with 4 samples). Binary classification support vector machine (SVM) models classified the disorder groups and HC. For each feature, the permutation feature importance was calculated, and the top 25% most important features were used to compare differences between the disorder groups and HC including correlations between the important features and symptom severity scores. Multiple kernels for SVM were tested and the pairwise models with the best performing kernel (3-degree polynomial) were highly accurate for each classification: 0.947 for HC vs. SSD, 0.920 for HC vs. MDD, and 0.932 for SSD vs. MDD. The relatively most important features were measures of articulation coordination, number of pauses per minute, and speech variability. There were moderate correlations between important features and positive symptoms for SSD. The important features suggest that speech characteristics relating to psychomotor slowing, alogia, and flat affect differ between HC, SSD, and MDD.