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Combinations of anti-cancer drugs can overcome resistance and provide new treatments1,2. The number of possible drug combinations vastly exceeds what could be tested clinically. Efforts to systematically identify active combinations and the tissues and molecular contexts in which they are most effective could accelerate the development of combination treatments. Here we evaluate the potency and efficacy of 2,025 clinically relevant two-drug combinations, generating a dataset encompassing 125 molecularly characterized breast, colorectal and pancreatic cancer cell lines. We show that synergy between drugs is rare and highly context-dependent, and that combinations of targeted agents are most likely to be synergistic. We incorporate multi-omic molecular features to identify combination biomarkers and specify synergistic drug combinations and their active contexts, including in basal-like breast cancer, and microsatellite-stable or KRAS-mutant colon cancer. Our results show that irinotecan and CHEK1 inhibition have synergistic effects in microsatellite-stable or KRAS-TP53 double-mutant colon cancer cells, leading to apoptosis and suppression of tumour xenograft growth. This study identifies clinically relevant effective drug combinations in distinct molecular subpopulations and is a resource to guide rational efforts to develop combinatorial drug treatments.
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Antineoplásicos , Neoplasias do Colo , Neoplasias Pancreáticas , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Combinação de Medicamentos , Sinergismo Farmacológico , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogênicas p21(ras)/genéticaRESUMO
Infections with the pathogenic free-living amoebae Naegleria fowleri can lead to life-threatening illnesses including catastrophic primary amoebic meningoencephalitis (PAM). Efficacious treatment options for these infections are lacking and the mortality rate remains >95% in the US. Glycolysis is very important for the infectious trophozoite lifecycle stage and inhibitors of glucose metabolism have been found to be toxic to the pathogen. Recently, human enolase 2 (ENO2) phosphonate inhibitors have been developed as lead agents to treat glioblastoma multiforme (GBM). These compounds, which cure GBM in a rodent model, are well-tolerated in mammals because enolase 1 (ENO1) is the predominant isoform used systemically. Here, we describe findings that demonstrate these agents are potent inhibitors of N. fowleri ENO (NfENO) and are lethal to amoebae. In particular, (1-hydroxy-2-oxopiperidin-3-yl) phosphonic acid (HEX) was a potent enzyme inhibitor (IC50 = 0.14 ± 0.04 µM) that was toxic to trophozoites (EC50 = 0.21 ± 0.02 µM) while the reported CC50 was >300 µM. Molecular docking simulation revealed that HEX binds strongly to the active site of NfENO with a binding affinity of -8.6 kcal/mol. Metabolomic studies of parasites treated with HEX revealed a 4.5 to 78-fold accumulation of glycolytic intermediates upstream of NfENO. Last, nasal instillation of HEX increased longevity of amoebae-infected rodents. Two days after infection, animals were treated for 10 days with 3 mg/kg HEX, followed by one week of observation. At the end of the one-week observation, eight of 12 HEX-treated animals remained alive (resulting in an indeterminable median survival time) while one of 12 vehicle-treated rodents remained, yielding a median survival time of 10.9 days. However, intranasal HEX delivery was not curative as brains of six of the eight survivors were positive for amoebae. These findings suggest that HEX requires further evaluation to develop as a lead for treatment of PAM.
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Infecções Protozoárias do Sistema Nervoso Central , Naegleria fowleri , Fosfopiruvato Hidratase , Animais , Naegleria fowleri/efeitos dos fármacos , Infecções Protozoárias do Sistema Nervoso Central/tratamento farmacológico , Infecções Protozoárias do Sistema Nervoso Central/parasitologia , Fosfopiruvato Hidratase/metabolismo , Fosfopiruvato Hidratase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Camundongos , Ratos , Humanos , Simulação de Acoplamento MolecularRESUMO
Current evidence suggests that plasma cell-free DNA (cfDNA) is fragmented around a mode of 166 bp. Data supporting this view has been mainly acquired through the analysis of double-stranded cfDNA. The characteristics and diagnostic potential of single-stranded and damaged double-stranded cfDNA in healthy individuals and cancer patients remain unclear. Here, through a combination of high-affinity magnetic bead-based DNA extraction and single-stranded DNA sequencing library preparation (MB-ssDNA), we report the discovery of a large proportion of cfDNA fragments centered at â¼50 bp. We show that these "ultrashort" cfDNA fragments have a greater relative abundance in plasma of healthy individuals (median = 19.1% of all sequenced cfDNA fragments, n = 28) than in plasma of patients with cancer (median = 14.2%, n = 21, P < 0.0001). The ultrashort cfDNA fragments map to accessible chromatin regions of blood cells, particularly in promoter regions with the potential to adopt G-quadruplex (G4) DNA secondary structures. G4-positive promoter chromatin accessibility is significantly enriched in ultrashort plasma cfDNA fragments from healthy individuals relative to patients with cancers (P < 0.0001), in whom G4-cfDNA enrichment is inversely associated with copy number aberration-inferred tumor fractions. Our findings redraw the landscape of cfDNA fragmentation by identifying and characterizing a novel population of ultrashort plasma cfDNA fragments. Sequencing of MB-ssDNA libraries could facilitate the characterization of gene regulatory regions and DNA secondary structures via liquid biopsy. Our data underline the diagnostic potential of ultrashort cfDNA through classification for cancer patients.
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Ácidos Nucleicos Livres , Neoplasias , Biomarcadores Tumorais/genética , Ácidos Nucleicos Livres/genética , DNA/genética , DNA de Cadeia Simples , Humanos , Neoplasias/diagnóstico , Neoplasias/genética , Análise de Sequência de DNARESUMO
Quantifying carbon fluxes into and out of coastal soils is critical to meeting greenhouse gas reduction and coastal resiliency goals. Numerous 'blue carbon' studies have generated, or benefitted from, synthetic datasets. However, the community those efforts inspired does not have a centralized, standardized database of disaggregated data used to estimate carbon stocks and fluxes. In this paper, we describe a data structure designed to standardize data reporting, maximize reuse, and maintain a chain of credit from synthesis to original source. We introduce version 1.0.0. of the Coastal Carbon Library, a global database of 6723 soil profiles representing blue carbon-storing systems including marshes, mangroves, tidal freshwater forests, and seagrasses. We also present the Coastal Carbon Atlas, an R-shiny application that can be used to visualize, query, and download portions of the Coastal Carbon Library. The majority (4815) of entries in the database can be used for carbon stock assessments without the need for interpolating missing soil variables, 533 are available for estimating carbon burial rate, and 326 are useful for fitting dynamic soil formation models. Organic matter density significantly varied by habitat with tidal freshwater forests having the highest density, and seagrasses having the lowest. Future work could involve expansion of the synthesis to include more deep stock assessments, increasing the representation of data outside of the U.S., and increasing the amount of data available for mangroves and seagrasses, especially carbon burial rate data. We present proposed best practices for blue carbon data including an emphasis on disaggregation, data publication, dataset documentation, and use of standardized vocabulary and templates whenever appropriate. To conclude, the Coastal Carbon Library and Atlas serve as a general example of a grassroots F.A.I.R. (Findable, Accessible, Interoperable, and Reusable) data effort demonstrating how data producers can coordinate to develop tools relevant to policy and decision-making.
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Carbono , Solo , Carbono/química , Solo/química , Ecossistema , Áreas Alagadas , PolíticasRESUMO
Open-shell materials bearing multiple spin centres provide a key route to efficient charge transport in single-molecule electronic devices. They have narrow energy gaps, and their molecular orbitals align closely to the Fermi level of the metallic electrodes, thus allowing efficient electronic transport and higher conductance. Maintaining and stabilising multiple open-shell states - especially in contact with metallic electrodes - is however very challenging, generally requiring a continuous chemical or electrochemical potential to avoid self-immolation of the open-shell character. To overcome this issue, we designed, synthesised, and measured the conductance of a series of bis(indeno) fused acenes, where stability is imparted by a close-shell quinoidal conformation in resonance with the diradical electronic configuration. We show here that these compounds have anti-ohmic behaviour, with conductance increasing with increasing molecular length, at an unprecedented rate and across the entire bias window ([[EQUATION]]). Density Functional Theory (DFT) calculations support our findings, showing the rapidly narrowing HOMO-LUMO gap, unique to these diradicaloid structures, is responsible for the observed behaviour. Our results provide a framework for achieving efficient transport in neutral compounds and demonstrate the promise that diradicaloid materials have in single-molecule electronics, owing to their great stability and unique electronic structure.
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Analysis of volatile organic compounds (VOCs) in exhaled breath (EB) has shown great potential for disease detection including lung cancer, infectious respiratory diseases, and chronic obstructive pulmonary disease. Although many breath sample collection and analytical methods have been developed for breath analysis, analysis of metabolic VOCs in exhaled breath is still a challenge for clinical application. Many carbonyl compounds in exhaled breath are related to the metabolic processes of diseases. This work reports a method of ultrahigh-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-MS) for the analysis of a broad range of carbonyl metabolites in exhaled breath. Carbonyl compounds in the exhaled breath were captured by a fabricated silicon microreactor with a micropillar array coated with 2-(aminooxy)ethyl-N,N,N-trimethylammonium (ATM) triflate. A total of six subgroups consisting of saturated aldehydes and ketones, hydroxy-aldehydes, and hydroxy-ketones, unsaturated 2-alkenals, and 4-hydroxy-2-alkenals were identified in the exhaled breath. The combination of a silicon microreactor for the selective capture of carbonyl compounds with UHPLC-MS analysis may provide a quantitative method for the analysis of carbonyls to identify disease markers in exhaled breath.
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Silício , Compostos Orgânicos Voláteis , Cromatografia Líquida de Alta Pressão , Compostos Orgânicos Voláteis/análise , Aldeídos/análise , Cetonas/análise , Testes Respiratórios/métodosRESUMO
Consolidative radiation therapy (RT) for advanced-stage diffuse large B-cell lymphoma (DLBCL) remains controversial, with routine practice continuing to include RT in patients with initial bulky disease or residual masses. Positron emission tomography (PET)-computed tomography is a sensitive modality for detecting the presence of residual disease at the end of treatment (EOT). A PET-guided approach to selectively administering RT has been the policy in British Columbia since 2005. Patients with advanced-stage DLBCL diagnosed from 1 January 2005 to 1 March 2017 and treated with at least 6 cycles of R-CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone plus rituximab), who underwent EOT PET, were included in this analysis. Those with complete metabolic response (PET-negative [PET-NEG]) were observed; those with PET-positive (PET-POS) scans were offered consolidative RT, when feasible. Of the patient records reviewed, 723 were identified, with median follow-up of 4.3 years: 517 (72%) were PET-NEG; 206 (28%) were PET-POS. Time to progression (TTP) and overall survival (OS) at 3 years were 83% vs 56% and 87% vs 64%, in patients with PET-NEG and PET-POS scans, respectively. PET-POS patients with nonprogressing disease treated with consolidative RT (109 and 206; 53%) had outcomes approaching those of PET-NEG patients, with 3-year estimates of 76% and 80% for TTP and OS. PET-NEG patients who had bulky disease (≥10 cm) at diagnosis had outcomes indistinguishable from those without bulk, despite the omission of RT. These data suggest that patients with advanced-stage DLBCL who are PET-NEG at EOT and receive no RT have excellent outcomes. 18F-fluorodeoxyglucose-PET can reliably guide selective administration of consolidative RT, even in patients with initially bulky disease.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma Difuso de Grandes Células B/radioterapia , Tomografia por Emissão de Pósitrons , Radioterapia Adjuvante/métodos , Radioterapia Guiada por Imagem/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Ciclofosfamida/administração & dosagem , Progressão da Doença , Doxorrubicina/administração & dosagem , Feminino , Radioisótopos de Flúor , Fluordesoxiglucose F18 , Humanos , Estimativa de Kaplan-Meier , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Rituximab/administração & dosagem , Método Simples-Cego , Resultado do Tratamento , Carga Tumoral , Vincristina/administração & dosagem , Adulto JovemRESUMO
BACKGROUND: Racial inequities exist in treatment and outcomes in patients with acute stroke. OBJECTIVES: Our objective was to determine if racial inequities exist in the time-lapse between patient presentation and provider assessment in patients with stroke-like symptoms in Emergency Departments (ED) across the U.S. METHODS: This study is a retrospective, observational study of the National Hospital Ambulatory Medical Care Survey (NHAMCS) 2014-2018. We identified visits with stroke-like symptoms and stratified the proportion of door-to-provider (DTP) times by racial groups. We used broad and narrow definitions of stroke-like symptoms. We performed bivariate and multivariate analyses using race and clinical and demographic characteristics as covariates. RESULTS: Between 2014-2018, there were an average of 138.58 million annual ED visits. Of the total ED visits, 0.36% to 7.39% of the ED visits presented with stroke-like symptoms, and the average DTP time ranged from 39 to 49 min. The proportion of the visits with a triage level of 1 (immediate) or 2 (emergent) ranged from 16.03% to 23.27% for stroke-like symptoms. We did not find statistically significant racial inequities in DTP or ED triage level. We found significantly longer DTP times in non-Hispanic blacks (15.88 min, 95% CI: 4.29-27.48) and Hispanics (by 14.77 min, 95% CI: 3.37-26.16) than non-Hispanic whites that presented with atypical stroke-like symptoms. We observed that non-Hispanic whites were significantly more diagnosed with a stroke/TIA than other racial minority groups (p = 0.045) for atypical stroke-like symptoms. CONCLUSION: In our population-based analysis, we did not identify systemic racial inequities in the DTP times or ED triage level at ED triage for stroke-like symptoms.
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Acidente Vascular Cerebral , Triagem , Humanos , Serviço Hospitalar de Emergência , Hispânico ou Latino , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Estados Unidos/epidemiologia , Disparidades em Assistência à Saúde/etnologia , Disparidades em Assistência à Saúde/estatística & dados numéricosRESUMO
Most studies in molecular electronics focus on altering the molecular wire backbone to tune the electrical properties of the whole junction. However, it is often overlooked that the chemical structure of the groups anchoring the molecule to the metallic electrodes influences the electronic structure of the whole system and, therefore, its conductance. We synthesised electron-accepting dithienophosphole oxide derivatives and fabricated their single-molecule junctions. We found that the anchor group has a dramatic effect on charge-transport efficiency: in our case, electron-deficient 4-pyridyl contacts suppress conductance, while electron-rich 4-thioanisole termini promote efficient transport. Our calculations show that this is due to minute changes in charge distribution, probed at the electrode interface. Our findings provide a framework for efficient molecular junction design, especially valuable for compounds with strong electron withdrawing/donating backbones.
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People with alcohol-related liver disease (ALD) experience stigma and discrimination. This review summarises the evidence on stigma in healthcare and its implications for people with ALD, drawing from the literature on the stigma associated with mental illness and, specifically, alcohol use disorder (AUD). Public stigma, self-stigma and structural stigma all contribute to failure to seek help or delays in seeking help, inferior healthcare, and negative health outcomes, which increase the overall burden of ALD. Stigma can be experienced, but also anticipated and avoided, with both scenarios negatively impacting on ALD healthcare. Blaming people with ALD for their condition is central to the stigma of ALD. Stigma affects ALD healthcare at all stages, from prevention, early detection and intervention, to allocation of scarce resources in liver transplantation. People with lived experience need to be empowered to lead action against the stigmatisation of patients with ALD. Promulgating a dynamic model of individual and social responsibility for AUD, a continuum model of harmful alcohol use, and establishing training on ALD-related stigma for healthcare professionals are strategies to address stigma. Integrating addiction and ALD services, providing stigma-free prevention, and overcoming the frequent separation of addiction services from general healthcare are necessary. Beyond healthcare, addressing social inequality, the social dimensions of ALD risk and outcomes, and ensuring equal access to services is necessary to improve outcomes for all people with ALD. More research is needed on the stigma of ALD in low- and middle-income countries and in countries with restrictive drinking norms. Interventions to reduce the stigma of ALD and facilitate early help-seeking need to be developed and evaluated.
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Alcoolismo , Hepatopatias , Atenção à Saúde , Pessoal de Saúde , Humanos , Estigma SocialRESUMO
Infection with pathogenic free-living amoebae, including Naegleria fowleri, Acanthamoeba spp., and Balamuthia mandrillaris, can lead to life-threatening illnesses, primarily because of catastrophic central nervous system involvement. Efficacious treatment options for these infections are lacking, and the mortality rate due to infection is high. Previously, we evaluated the N. fowleri glucokinase (NfGlck) as a potential target for therapeutic intervention, as glucose metabolism is critical for in vitro viability. Here, we extended these studies to the glucokinases from two other pathogenic free-living amoebae, including Acanthamoeba castellanii (AcGlck) and B. mandrillaris (BmGlck). While these enzymes are similar (49.3% identical at the amino acid level), they have distinct kinetic properties that distinguish them from each other. For ATP, AcGlck and BmGlck have apparent Km values of 472.5 and 41.0 µM, while Homo sapiens Glck (HsGlck) has a value of 310 µM. Both parasite enzymes also have a higher apparent affinity for glucose than the human counterpart, with apparent Km values of 45.9 µM (AcGlck) and 124 µM (BmGlck) compared to ~8 mM for HsGlck. Additionally, AcGlck and BmGlck differ from each other and other Glcks in their sensitivity to small molecule inhibitors, suggesting that inhibitors with pan-amoebic activity could be challenging to generate.
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Acanthamoeba , Amebíase , Amoeba , Balamuthia mandrillaris , Naegleria fowleri , Amebíase/tratamento farmacológico , Amebíase/parasitologia , Glucoquinase , HumanosRESUMO
INTRODUCTION: Healthcare expenditure is on the rise placing greater emphasis on operational excellence, cost containment, and high quality of care. Significant variation is seen in operating room (OR) costs with common surgical procedures such as laparoscopic appendectomy. Surgeons can influence cost through the selection of instrumentation for common surgical procedures such as laparoscopic appendectomy. We aimed to quantify the cost of laparoscopic appendectomy in our healthcare system and compare cost variations to operative times and outcomes. METHODS AND PROCEDURES: We performed a retrospective review of laparoscopic appendectomies in a large regional healthcare system during one-year period (2018). Operating room supply costs and procedure durations were obtained for each hospital. The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) outcomes and demographics were compared to the costs for each hospital. RESULTS: A total of 4757 laparoscopic appendectomies were performed at 20 hospitals (27 to 522 per hospital) by 233 surgeons. The average supply cost per case ranged from $650 to $1067. Individual surgeon cost ranged from $197 to $1181. The average operative time was 41 min (range 33 to 60 min). There was no association between lower cost and longer operative time. The patient demographics and comorbidities were similar between sites. There were no significant differences in postoperative complications between high- and low-cost centers. The items with the greatest increase in cost were single-use energy devices (SUD) and endoscopic stapler. We estimate that a saving of over $417 per case is possible by avoiding the use of energy devices and may be as high as $ 984 by adding selective use of staplers. These modifications would result in an annual savings of $1 million for our health system and more than $ 125 million nationwide. CONCLUSION: Performing laparoscopic appendectomy with reusable instruments and finding alternatives to expensive energy devices and staplers can significantly decrease costs and does not increase operative time or postoperative complications.
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Apendicite , Prestação Integrada de Cuidados de Saúde , Laparoscopia , Apendicectomia/métodos , Apendicite/cirurgia , Controle de Custos , Humanos , Laparoscopia/métodos , Duração da Cirurgia , Estudos RetrospectivosRESUMO
OBJECTIVES: Pediatric skull fracture association with the cranial sutures (crossing, widening, or contacting 2 or more cranial sutures) is suggestive of abusive injury. We studied the efficacy of head computed tomography (CT) versus skull radiographs in identifying pediatric skull fracture association with cranial sutures and reviewed head CT literature recommendations for pediatric head trauma. METHODS: Retrospective review was performed of skull radiographs and head CT at a tertiary care, free-standing children's hospital (2012-2019). Statistical 2-proportion Z test determined efficacy of head CT versus skull radiographs in assessing cranial suture involvement with fractures. RESULTS: Forty-seven children with 56 abusive skull fractures and 47 children with 54 accidental skull fractures were evaluated, ages 1 to 36 months. Of the 110 total skull fractures evaluated, 51 abusive and 41 accidental skull fractures had terminal ends contacting cranial sutures for a total of 92 (84%). Twelve abusive fractures (24%) crossed sutures; no accidental fractures crossed sutures (P < 0.01). Of the 12 abusive cases with skull fractures that crossed sutures, 7 were definitively identified only on CT (P < 0.01). Widened sutures were documented in 4 (8%) of the abusive cases with skull fracture; none in the accidental cases. All 4 of these cases were equally identified on both skull radiography and CT imaging. In 21 of 47 abusive versus 5 of 47 accidental cases, CT identified skull fractures lines that extended to cranial sutures that were not definitive on skull radiography (P = 0.00022). CONCLUSIONS: Cranial suture involvement with pediatric skull fractures is common. Head CT significantly aided in the identification of skull fractures contacting and crossing cranial sutures in abusive cases, supporting eliminating concurrent skull radiographs.
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Lesões Acidentais , Maus-Tratos Infantis , Traumatismos Craniocerebrais , Fraturas Cranianas , Criança , Maus-Tratos Infantis/diagnóstico , Pré-Escolar , Suturas Cranianas/diagnóstico por imagem , Traumatismos Craniocerebrais/diagnóstico por imagem , Humanos , Lactente , Estudos Retrospectivos , Fraturas Cranianas/diagnóstico por imagem , Fraturas Cranianas/etiologia , SuturasRESUMO
Strategies commonly used for the synthesis of functionalised bicyclo[1.1.1]pentanes (BCP) rely on the reaction of [1.1.1]propellane with anionic or radical intermediates. In contrast, electrophilic activation has remained a considerable challenge due to the facile decomposition of BCP cations, which has severely limited the applications of this strategy. Herein, we report the electrophilic activation of [1.1.1]propellane in a halogen bond complex, which enables its reaction with electron-neutral nucleophiles such as anilines and azoles to give nitrogen-substituted BCPs that are prominent motifs in drug discovery. A detailed computational analysis indicates that the key halogen bonding interaction promotes nucleophilic attack without sacrificing cage stabilisation. Overall, our work rehabilitates electrophilic activation of [1.1.1]propellane as a valuable strategy for accessing functionalised BCPs.
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Herbicide resistance in weeds can be conferred by target-site and/or non-target-site mechanisms, such as rapid metabolic detoxification. Resistance to the very-long-chain fatty acid-inhibiting herbicide, S-metolachlor, in multiple herbicide-resistant populations (CHR and SIR) of waterhemp (Amaranthus tuberculatus) is conferred by rapid metabolism compared with sensitive populations. However, enzymatic pathways for S-metolachlor metabolism in waterhemp are unknown. Enzyme assays using S-metolachlor were developed to determine the specific activities of glutathione S-transferases (GSTs) and cytochrome P450 monooxygenases (P450s) from CHR and SIR seedlings to compare with tolerant corn and sensitive waterhemp (WUS). GST activities were greater (â¼2-fold) in CHR and SIR compared to WUS but much less than corn. In contrast, P450s in microsomal extracts from CHR and SIR formed O-demethylated S-metolachlor, and their NADPH-dependent specific activities were greater (>20-fold) than corn or WUS. Metabolite profiles of S-metolachlor generated via untargeted and targeted liquid chromatography-mass spectrometry from CHR and SIR differed from WUS, with greater relative abundances of O-demethylated S-metolachlor and O-demethylated S-metolachlor-glutathione conjugates formed by CHR and SIR. In summary, our results demonstrate that S-metolachlor metabolism in resistant waterhemp involves Phase I and Phase II metabolic activities acting in concert, but the initial O-demethylation reaction confers resistance.
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Acetamidas/farmacologia , Amaranthus/metabolismo , Resistência a Herbicidas , Herbicidas/farmacologia , Zea mays/metabolismo , Amaranthus/efeitos dos fármacos , Redes e Vias Metabólicas , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/metabolismo , Zea mays/efeitos dos fármacosRESUMO
Low success rates during drug development are due, in part, to the difficulty of defining drug mechanism-of-action and molecular markers of therapeutic activity. Here, we integrated 199,219 drug sensitivity measurements for 397 unique anti-cancer drugs with genome-wide CRISPR loss-of-function screens in 484 cell lines to systematically investigate cellular drug mechanism-of-action. We observed an enrichment for positive associations between the profile of drug sensitivity and knockout of a drug's nominal target, and by leveraging protein-protein networks, we identified pathways underpinning drug sensitivity. This revealed an unappreciated positive association between mitochondrial E3 ubiquitin-protein ligase MARCH5 dependency and sensitivity to MCL1 inhibitors in breast cancer cell lines. We also estimated drug on-target and off-target activity, informing on specificity, potency and toxicity. Linking drug and gene dependency together with genomic data sets uncovered contexts in which molecular networks when perturbed mediate cancer cell loss-of-fitness and thereby provide independent and orthogonal evidence of biomarkers for drug development. This study illustrates how integrating cell line drug sensitivity with CRISPR loss-of-function screens can elucidate mechanism-of-action to advance drug development.
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Antineoplásicos/farmacologia , Sistemas CRISPR-Cas , Desenvolvimento de Medicamentos/métodos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Redes Reguladoras de Genes/efeitos dos fármacos , Aptidão Genética/efeitos dos fármacos , Mapas de Interação de Proteínas/efeitos dos fármacos , Antineoplásicos/toxicidade , Biomarcadores/metabolismo , Linhagem Celular Tumoral , Técnicas de Inativação de Genes , Redes Reguladoras de Genes/genética , Aptidão Genética/genética , Genômica , Humanos , Modelos Lineares , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Preparações Farmacêuticas/metabolismo , Software , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Metabolic resistance to 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicides is a threat in controlling waterhemp (Amaranthus tuberculatus) in the USA. We investigated resistance mechanisms to syncarpic acid-3 (SA3), a nonselective, noncommercial HPPD-inhibiting herbicide metabolically robust to Phase I oxidation, in multiple-herbicide-resistant (MHR) waterhemp populations (SIR and NEB) and HPPD inhibitor-sensitive populations (ACR and SEN). Dose-response experiments with SA3 provided ED50 -based resistant : sensitive ratios of at least 18-fold. Metabolism experiments quantifying parent SA3 remaining in excised leaves during a time course indicated MHR populations displayed faster rates of SA3 metabolism compared to HPPD inhibitor-sensitive populations. SA3 metabolites were identified via LC-MS-based untargeted metabolomics in whole plants. A Phase I metabolite, likely generated by cytochrome P450-mediated alkyl hydroxylation, was detected but was not associated with resistance. A Phase I metabolite consistent with ketone reduction followed by water elimination was detected, creating a putative α,ß-unsaturated carbonyl resembling a Michael acceptor site. A Phase II glutathione-SA3 conjugate was associated with resistance. Our results revealed a novel reduction-dehydration-GSH conjugation detoxification mechanism. SA3 metabolism in MHR waterhemp is thus atypical compared to commercial HPPD-inhibiting herbicides. This previously uncharacterized detoxification mechanism presents a unique opportunity for future biorational design by blocking known sites of herbicide metabolism in weeds.
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4-Hidroxifenilpiruvato Dioxigenase , Amaranthus , Dioxigenases , Herbicidas , Desidratação , Glutationa , Resistência a Herbicidas , Herbicidas/farmacologiaRESUMO
BACKGROUND: People with chronic kidney disease (CKD) are at high risk of polypharmacy. However, no previous study has investigated international prescribing patterns in this group. This article aims to examine prescribing and polypharmacy patterns among older people with advanced CKD across the countries involved in the European Quality (EQUAL) study. METHODS: The EQUAL study is an international prospective cohort study of patients ≥65 years of age with advanced CKD. Baseline demographic, clinical and medication data were analysed and reported descriptively. Polypharmacy was defined as ≥5 medications and hyperpolypharmacy as ≥10. Univariable and multivariable linear regressions were used to determine associations between country and the number of prescribed medications. Univariable and multivariable logistic regression were used to determine associations between country and hyperpolypharmacy. RESULTS: Of the 1317 participants from five European countries, 91% were experiencing polypharmacy and 43% were experiencing hyperpolypharmacy. Cardiovascular medications were the most prescribed medications (mean 3.5 per person). There were international differences in prescribing, with significantly greater hyperpolypharmacy in Germany {odds ratio (OR) 2.75 [95% confidence interval (CI) 1.73-4.37]; P < 0.001, reference group UK}, the Netherlands [OR 1.91 (95% CI 1.32-2.76); P = 0.001] and Italy [OR 1.57 (95% CI 1.15-2.15); P = 0.004]. People in Poland experienced the least hyperpolypharmacy [OR 0.39 (95% CI 0.17-0.87); P = 0.021]. CONCLUSIONS: Hyperpolypharmacy is common among older people with advanced CKD, with significant international differences in the number of medications prescribed. Practice variation may represent a lack of consensus regarding appropriate prescribing for this high-risk group for whom pharmacological treatment has great potential for harm as well as benefit.
Assuntos
Prescrição Inadequada/prevenção & controle , Preparações Farmacêuticas/administração & dosagem , Polimedicação , Padrões de Prática Médica/estatística & dados numéricos , Garantia da Qualidade dos Cuidados de Saúde , Insuficiência Renal Crônica/tratamento farmacológico , Idoso , Feminino , Alemanha/epidemiologia , Humanos , Itália/epidemiologia , Masculino , Países Baixos/epidemiologia , Polônia/epidemiologia , Estudos Prospectivos , Pesquisa Qualitativa , Insuficiência Renal Crônica/epidemiologiaRESUMO
OBJECTIVE. The purpose of this study was to assess the incidence of pediatric skull fractures contacting cranial sutures in abusive versus accidental trauma. MATERIALS AND METHODS. A retrospective review was conducted of head CT studies performed for pediatric head trauma at a free-standing tertiary care children's hospital from 2012 to 2019. Statistical odds ratios were evaluated to assess the significance of skull fracture extension to sutures in abusive versus accidental injury. A two-proportion Z-test was used to determine the statistical significance of suture type contacted by skull fractures in accidental versus abusive injury. RESULTS. The records of 47 children with 57 abusive skull fractures and 47 children with 54 accidental skull fractures were evaluated. The patients were 1-36 months old. Fifty-one abusive skull fractures (89%) terminated in contact with a cranial suture; 35 of the 51 (69%) touched two or more sutures, and 12 touched three or more sutures. Forty-two of the 54 (78%) accidental skull fractures contacted a suture; only 3 of the 42 (7%) touched two sutures, and none touched more than two sutures (odds ratio, 28.4 [95% CI, 7.6-105.9]; p < .001). In the abusive fractures, the suture most commonly contacted by a fracture line was the lambdoid (43%; p < .04), followed by the sagittal (23%), coronal (21%), temporal-squamous (12%), and metopic (1%) sutures. There was no statistical difference in which suture was contacted by fracture lines in accidental cases. CONCLUSION. Skull fracture contacting cranial sutures is common in abusive and accidental pediatric head trauma. However, that a fracture contacts two or more cranial sutures is an imaging finding not previously described that has a significantly higher association with abusive than with accidental head injury.
Assuntos
Maus-Tratos Infantis/estatística & dados numéricos , Traumatismos Craniocerebrais/diagnóstico por imagem , Traumatismos Craniocerebrais/terapia , Fraturas Cranianas/diagnóstico por imagem , Fraturas Cranianas/terapia , Suturas/estatística & dados numéricos , Tomografia Computadorizada por Raios X/métodos , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos RetrospectivosRESUMO
In this review, the synthesis of 33 agrochemicals that received an international standardization organization (ISO) name between January 2015 and December 2018 is described. The aim is to showcase the broad range and scope of reactions, reagents and intermediates used to discover and produce the latest active ingredients addressing the crop protection industry's needs.