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Androgen receptor (AR) signaling plays a key role in the progression of prostate cancer. This study describes the discovery and optimization of a novel series of AR PROTAC degraders that recruit the Cereblon (CRBN) E3 ligase. Having identified a series of AR ligands based on 4-(4-phenyl-1-piperidyl)-2-(trifluoromethyl)benzonitrile, our PROTAC optimization strategy focused on linker connectivity and CRBN ligand SAR to deliver potent degradation of AR in LNCaP cells. This work culminated in compounds 11 and 16 which demonstrated good rodent oral bioavailability. Subsequent SAR around the AR binding region brought in an additional desirable feature, degradation of the important treatment resistance mutation L702H. Compound 22 (AZ'3137) possessed an attractive profile showing degradation of AR and L702H mutant AR with good oral bioavailability across species. The compound also inhibited AR signaling in vitro and tumor growth in vivo in a mouse prostate cancer xenograft model.
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Disponibilidade Biológica , Neoplasias da Próstata , Receptores Androgênicos , Masculino , Animais , Humanos , Receptores Androgênicos/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/metabolismo , Administração Oral , Camundongos , Linhagem Celular Tumoral , Relação Estrutura-Atividade , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacocinética , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/química , Antagonistas de Receptores de Andrógenos/uso terapêutico , Antagonistas de Receptores de Andrógenos/farmacocinética , Descoberta de Drogas , Ensaios Antitumorais Modelo de Xenoenxerto , RatosRESUMO
Covalent hit identification is a viable approach to identify chemical starting points against difficult-to-drug targets. While most researchers screen libraries of <2k electrophilic fragments, focusing on lead-like compounds can be advantageous in terms of finding hits with improved affinity and with a better chance of identifying cryptic pockets. However, due to the increased molecular complexity, larger numbers of compounds (>10k) are desirable to ensure adequate coverage of chemical space. Herein, the approach taken to build a library of 12k covalent lead-like compounds is reported, utilizing legacy compounds, robust library chemistry, and acquisitions. The lead-like covalent library was screened against the antiapoptotic protein Bfl-1, and six promising hits that displaced the BIM peptide from the PPI interface were identified. Intriguingly, X-ray crystallography of lead-like compound 8 showed that it binds to a previously unobserved conformation of the Bfl-1 protein and is an ideal starting point for the optimization of Bfl-1 inhibitors.
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Cisteína , Desenho de Fármacos , Bibliotecas de Moléculas Pequenas , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Cristalografia por Raios X , Cisteína/química , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/química , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Relação Estrutura-Atividade , Modelos Moleculares , Antígenos de Histocompatibilidade MenorRESUMO
The glycine to cysteine mutation at codon 12 of Kirsten rat sarcoma (KRAS) represents an Achilles heel that has now rendered this important GTPase druggable. Herein, we report our structure-based drug design approach that led to the identification of 14, AZD4747, a clinical development candidate for the treatment of KRASG12C-positive tumors, including the treatment of central nervous system (CNS) metastases. Building on our earlier discovery of C5-tethered quinazoline AZD4625, excision of a usually critical pyrimidine ring yielded a weak but brain-penetrant start point which was optimized for potency and DMPK. Key design principles and measured parameters that give high confidence in CNS exposure are discussed. During optimization, divergence between rodent and non-rodent species was observed in CNS exposure, with primate PET studies ultimately giving high confidence in the expected translation to patients. AZD4747 is a highly potent and selective inhibitor of KRASG12C with an anticipated low clearance and high oral bioavailability profile in humans.
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Antineoplásicos , Neoplasias Pulmonares , Neoplasias , Animais , Humanos , Antineoplásicos/farmacologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias/tratamento farmacológico , Desenho de Fármacos , Glicina/uso terapêutico , Mutação , Neoplasias Pulmonares/tratamento farmacológicoRESUMO
BACKGROUND: Gay, bisexual and other men who have sex with men (GBMSM) are overrepresented in cohorts of people who inject drugs. GBMSM's substance use is usually explored in the context of its contribution to sexual risk. We examined drug use practices, connectedness to other people who inject drugs, peer-to-peer injecting, and access to care among men who inject drugs in Melbourne, Australia. We aim to describe similarities and differences in these parameters for GBMSM and other men. METHODS: Data were drawn from a prospective cohort study of people who inject drugs conducted in Melbourne, Australia, since 2009. This cross-sectional study used data collected between 2016 and 2021. Descriptive statistics were used to assess differences between GBMSM and other men. RESULTS: Of 525 men who injected drugs over the study period, 48 (9%) identified as gay or bisexual, or reported sex with other men in the past 12 months. GBMSM and other men reported similar socio-demographics, drug practices (age of injecting initiation, most injected drug, peer-to-peer injecting, receptive syringe sharing) and access to injecting-specific care (drug treatment, source of needle-syringes). A significantly greater percentage of GBMSM reported past 12-month hepatitis C testing (69% vs. 52%, p = 0.028) and preferring methamphetamine (31% vs. 16%, p = 0.022). A higher percentage of GBMSM reported knowing > 50 other people who inject drugs (46% vs. 37%), but this difference was not statistically significant. Both groups primarily obtained injecting equipment from needle-syringe programs; a minority had accessed injecting-specific primary care. CONCLUSION: Men who injected drugs in this cohort and those who identified as GBMSM reported similar drug and health-seeking practices. The higher prevalence of methamphetamine injecting among GBMSM may warrant different harm reduction support for this group. Health promotion should utilise opportunities to connect men who inject drugs in Melbourne to injecting-specific primary health care.
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Metanfetamina , Minorias Sexuais e de Gênero , Abuso de Substâncias por Via Intravenosa , Transtornos Relacionados ao Uso de Substâncias , Masculino , Humanos , Abuso de Substâncias por Via Intravenosa/epidemiologia , Estudos Transversais , Homossexualidade Masculina , Estudos Prospectivos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Austrália/epidemiologiaRESUMO
Objective: This descriptive feasibility study aimed to assess dietary intake, sports nutrition knowledge, and nutrition information source in collegiate athletes. Participants: Fourteen indoor volleyball female collegiate athletes from a National Collegiate Athletic Association Division I university. Methods: Participants completed a Nutrition for Sports Knowledge Questionnaire (NSKQ) once and dietary and body composition assessments over four time points. Results: Pre-season mean energy and carbohydrate intake were lower than the American College of Sports Medicine Recommendations (25 ± 6.4 vs 37-41 kcal/kg BW/day and 3 ± 0.9 vs 6-10 g/kg BW/day; respectively). Off-season carbohydrate intake followed similar trends. The average score on the NSKQ was 45 ± 9.6% out of 100. Athletic trainers were identified as a top nutrition source followed by strength and conditioning coaches and nutritionists. Conclusion: Female volleyball athletes have inadequate dietary intake and sports nutrition knowledge and may benefit from nutrition education and counseling by trained sports nutrition experts.Supplemental data for this article can be accessed online at https://doi.org/10.1080/07448481.2021.1987919.
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Fonte de Informação , Esportes , Humanos , Feminino , Estudos de Viabilidade , Universidades , Estudantes , Atletas , Ingestão de Alimentos , CarboidratosRESUMO
BACKGROUND: Gay and bisexual men (GBM) have higher substance use prevalences than general population samples - often attributed to stigmatisation of sexual minority identities. We examined how influential public health research on substance use among GBM interprets this behaviour and what GBM-specific identities emerge through the discourses employed. METHODS: We searched Web of Science for publications on substance use among GBM, selecting 60 of the most cited papers published during 2000-2020. We studied the language used to describe and interpret drug-using behaviour using critical discourse analysis, focusing on interpretive repertoires and subject positions. RESULTS: Three distinct discursive tendencies were identified. First, in constructing a target population, GBM who use illicit drugs are positioned as deficient, socially irresponsible, and maladapted to dealing with stigmatisation and HIV risks. Second, in shifting the focus beyond the individual, the gay community is conceptualised as offering a safe space for socialisation. Nonetheless, gay community spaces are problematised as promoting substance use among vulnerable GBM through aggravating loneliness and normalising drug use as a form of maladaptive (avoidance) coping. Third, counterdiscursive movements add nuance, context, and comparisons that relativise rather than generalise substance use and focus on pleasure and self-determination. Such discourses centre the need for interventions that disrupt homophobic socio-structures instead of individualising approaches to limit non-conformity. CONCLUSION: 'Expert' assessments of substance use among GBM perpetuate pathologising understandings of this behaviour and promote abject subject positions, contributing to perpetuations of intergroup stigma and social exclusion based on drug and sexual practices. Our findings highlight the need for deliberate and critical engagement with prior research and a conscious effort to disrupt dominant discourses on GBM's substance use.
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Drogas Ilícitas , Minorias Sexuais e de Gênero , Transtornos Relacionados ao Uso de Substâncias , Bissexualidade , Homossexualidade Masculina , Humanos , Masculino , Saúde Pública , Comportamento Sexual , Transtornos Relacionados ao Uso de Substâncias/epidemiologiaRESUMO
miR-486 is a muscle-enriched microRNA, or "myomiR," that has reduced expression correlated with Duchenne muscular dystrophy (DMD). To determine the function of miR-486 in normal and dystrophin-deficient muscles and elucidate miR-486 target transcripts in skeletal muscle, we characterized mir-486 knockout mice (mir-486 KO). mir-486 KO mice developed disrupted myofiber architecture, decreased myofiber size, decreased locomotor activity, increased cardiac fibrosis, and metabolic defects were exacerbated in mir-486 KO:mdx 5cv (DKO) mice. To identify direct in vivo miR-486 muscle target transcripts, we integrated RNA sequencing and chimeric miRNA eCLIP sequencing to identify key transcripts and pathways that contribute towards mir-486 KO and dystrophic disease pathologies. These targets included known and novel muscle metabolic and dystrophic structural remodeling factors of muscle and skeletal muscle contractile transcript targets. Together, our studies identify miR-486 as essential for normal muscle function, a driver of pathological remodeling in dystrophin-deficient muscle, a useful biomarker for dystrophic disease progression, and highlight the use of multiple omic platforms to identify in vivo microRNA target transcripts.
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Distrofina , MicroRNAs , Animais , Distrofina/genética , Camundongos , Camundongos Endogâmicos mdx , MicroRNAs/genética , MicroRNAs/metabolismo , Músculo Esquelético/metabolismo , Transcriptoma/genéticaRESUMO
KRAS is an archetypal high-value intractable oncology drug target. The glycine to cysteine mutation at codon 12 represents an Achilles heel that has now rendered this important GTPase druggable. Herein, we report our structure-based drug design approach that led to the identification of 21, AZD4625, a clinical development candidate for the treatment of KRASG12C positive tumors. Highlights include a quinazoline tethering strategy to lock out a bio-relevant binding conformation and an optimization strategy focused on the reduction of extrahepatic clearance mechanisms seen in preclinical species. Crystallographic analysis was also key in helping to rationalize unusual structure-activity relationship in terms of ring size and enantio-preference. AZD4625 is a highly potent and selective inhibitor of KRASG12C with an anticipated low clearance and high oral bioavailability profile in humans.
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Antineoplásicos , Neoplasias Pulmonares , Antineoplásicos/farmacologia , Desenho de Fármacos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Quinazolinas/farmacologia , Relação Estrutura-AtividadeRESUMO
A reagent-controlled stereodivergent carbocyclisation of aryl aldimine-derived, photocatalytically generated, α-amino radicals possessing adjacent conjugated alkenes, affording either bicyclic or tetracyclic products, is described. Under net reductive conditions using commercial Hantzsch ester, the α-amino radical species underwent a single stereoselective cyclisation to give trans-configured amino-indane structures in good yield, whereas using a substituted Hantzsch ester as a milder reductant afforded cis-fused tetracyclic tetrahydroquinoline frameworks, resulting from two consecutive radical cyclisations. Judicious choice of the reaction conditions allowed libraries of both single and dual cyclisation products to be synthesised with high selectivity, notable predictability, and good-to-excellent yields. Computational analysis employing DFT revealed the reaction pathway and mechanistic rationale behind this finely balanced yet readily controlled photocatalytic system.
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BACKGROUND: Taurine has become a popular supplement among athletes attempting to improve performance. While the effectiveness of taurine as an ergogenic aid remains controversial, this paper summarizes the current evidence regarding the efficacy of taurine in aerobic and anaerobic performance, metabolic stress, muscle soreness, and recovery. METHODS: Google Scholar, Web of Science, and MedLine (PubMed) searches were conducted through September 2020. Peer-reviewed studies that investigated taurine as a single ingredient at dosages of < 1 g - 6 g, ranging from 10 to 15 min-to-2 h prior to exercise bout or chronic dose (7 days- 8 weeks) of consumption were included. Articles were excluded if taurine was not the primary or only ingredient in a supplement or food source, not published in peer-reviewed journals, if participants were older than 50 years, articles published before 1999, animal studies, or included participants with health issues. A total of 19 studies met the inclusion criteria for the review. RESULTS: Key results include improvements in the following: VO2max, time to exhaustion (TTE; n = 5 articles), 3 or 4 km time-trial (n = 2 articles), anaerobic performance (n = 7 articles), muscle damage (n = 3 articles), peak power (n = 2 articles), recovery (n = 1 article). Taurine also caused a change in metabolites: decrease in lactate, creatine kinase, phosphorus, inflammatory markers, and improved glycolytic/fat oxidation markers (n = 5 articles). Taurine dosing appears to be effective at ~ 1-3 g/day acutely across a span of 6-15 days (1-3 h before an activity) which may improve aerobic performance (TTE), anaerobic performance (strength, power), recovery (DOMS), and a decrease in metabolic markers (creatine kinase, lactate, inorganic phosphate). CONCLUSIONS: Limited and varied findings prohibit definitive conclusions regarding the efficacy of taurine on aerobic and anaerobic performance and metabolic outcomes. There are mixed findings for the effect of taurine consumption on improving recovery from training bouts and/or mitigating muscle damage. The timing of taurine ingestion as well as the type of exercise protocol performed may contribute to the effectiveness of taurine as an ergogenic aid. More investigations are needed to better understand the potential effects of taurine supplementation on aerobic and anaerobic performance, muscle damage, metabolic stress, and recovery.
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Desempenho Atlético/fisiologia , Suplementos Nutricionais , Substâncias para Melhoria do Desempenho/administração & dosagem , Taurina/administração & dosagem , Glicemia/metabolismo , Regulação da Temperatura Corporal , Cálcio/metabolismo , Metabolismo Energético , Humanos , Inflamação/prevenção & controle , Ácido Láctico/sangue , Metabolismo dos Lipídeos , Força Muscular , Mialgia/prevenção & controle , Estresse Oxidativo , Consumo de Oxigênio , Substâncias para Melhoria do Desempenho/farmacocinética , Taurina/farmacocinéticaRESUMO
In recent years, the emergence of targeted covalent inhibitors which bind to the G12C mutant of KRAS have offered a solution to this previously intractable target. Inhibitors of KRASG12C tend to be structurally complex, displaying features such as atropisomerism, chiral centres and a reactive covalent warhead. Such molecules result in lengthy and challenging syntheses, and as a consequence critical decisions need to be made at the design level to maximise the chances of success. Here we take a retrospective look into how computational chemistry can help guide and prioritise medicinal chemistry efforts in the context of a series of conformationally restricted tetracyclic quinolines.
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ABSTRACT: Brandenberger, KJ, Warren, GL, Ingalls, CP, Otis, JS, and Doyle, JA. Downhill running impairs activation and strength of the elbow flexors. J Strength Cond Res 35(8): 2145-2150, 2021-The purpose of this study was to determine if knee extensor injury induced by 1 hour of downhill running attenuated force production in the elbow flexors. Subjects completed either downhill running for 1 hour (injured group; n = 6) or sedentary behavior (control group; n = 6). Strength and voluntary activation (%VA) were measured by isometric twitch interpolation of the elbow flexor and knee extensor muscles at the following time points in relation to the injury: before injury (Pre), after injury (Post), 24 hours after injury (24Post), and 48 hours after injury (48Post). Mean (±SE) knee extensor strength was significantly reduced (53.5 ± 9.9%) Post and remained reduced at 24Post and 48Post in the injury group. Knee extensor muscle twitch strength was reduced Post and 24Post after the downhill run (p < 0.022). Elbow flexor muscle strength was significantly reduced Post (13.2 ± 3.9%) and 24Post (17.3 ± 4.0%). Elbow flexor muscle twitch strength was not significantly different at any time point. Elbow flexor muscle %VA was not significantly reduced compared with Pre, at Post (16.2 ± 5.1%), 24Post (20.9 ± 6.7%), or 48Post (12.9 ± 4.5%). A 1-hour downhill run significantly injured the knee extensors. The elbow flexor muscles remained uninjured, but strength of these muscles was impaired by reduced %VA. These data suggest muscle injury can lead to prolonged strength deficits in muscles distant from the injury and should be accounted for when scheduling training that may lead to delayed-onset muscle soreness.
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Cotovelo , Força Muscular , Humanos , Joelho , Articulação do Joelho , Músculo EsqueléticoRESUMO
BACKGROUND: The global coronavirus disease 2019 (COVID-19) pandemic caused state-wide shutdowns of elective surgical activities in March and April of 2020 forcing graduate medical education program directors and their trainees in the United States to quickly adapt to new rules and circumstances. AIM: The aim of this study was to determine the effect of the current pandemic on pediatric anesthesiology fellow education and wellness nationally in order to guide creation of optimal support systems for fellows during the ongoing pandemic. METHODS: In July 2020, an electronically distributed survey was sent to all United States-based pediatric anesthesiology fellowship program directors who were asked to distribute the survey to all current/graduating fellows. RESULTS: A total of 75 out of 184 pediatric anesthesiology fellows (41%) responded to the survey. Major domains identified include reduction of clinical time, financial impact, mental health/wellness effects, and concerns about the overall quality of the fellowship educational experience. Respondents indicated that the pandemic has led to personal quarantine (and/or illness) leave time (21.3%), changes in finances (42.7%) and career opportunities (37.3%), decreased clinical education/experience (28%), and a dissatisfaction with the modified didactic experience (22.7%). In addition, a majority of respondents (97.3%) experienced increased stressors during this pandemic, including worry for family members (80%), stress due to changes in certifying examinations (76%), and fear of contracting COVID-19 from a patient (72%). CONCLUSION: While the results of this survey are only one snapshot in time during an evolving pandemic, these results highlight important domains where program directors and other departmental leaders might focus limited resources to maximize the educational experiences and overall wellness for pediatric anesthesiology fellows.
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Anestesiologia/educação , COVID-19/prevenção & controle , Bolsas de Estudo/métodos , Nível de Saúde , Saúde Mental , Pediatria/educação , Educação de Pós-Graduação em Medicina/métodos , Inquéritos Epidemiológicos/métodos , Inquéritos Epidemiológicos/estatística & dados numéricos , Humanos , Pandemias , SARS-CoV-2 , Estados UnidosRESUMO
BACKGROUND: Blood transfusions in the neonatal patient population are common, but there are no established guidelines regarding transfusion thresholds. Little is known about postoperative outcomes in neonates who receive preoperative blood transfusions (PBTs). METHODS: Using the American College of Surgeons National Surgical Quality Improvement Program-Pediatric Participant Use Data Files from 2012 to 2015, we identified all neonates who underwent surgery. Mortality and composite morbidity (defined as any postoperative complication) in neonates who received a PBT within 48 hours of surgery were compared with that in neonates who did not receive a transfusion. RESULTS: A total of 12 184 neonates were identified, of whom 1209 (9.9%) received a PBT. Neonates who received a PBT had higher rates of preoperative comorbidities and worse postoperative outcomes when compared with those who did not receive a transfusion (composite morbidity: 46.2% vs 16.2%; P < .01). On multivariable regression analysis, PBTs were independently associated with increased 30-day morbidity (odds ratio [OR] = 1.90; 95% confidence interval [CI]: 1.63-2.22; P < .01) and mortality (OR = 1.98; 95% CI: 1.55-2.55; P < .01). In a propensity score-matched analysis, PBTs continued to be associated with increased 30-day morbidity (OR = 1.53; 95% CI: 1.29-1.81; P < .01) and mortality (OR = 1.58; 95% CI: 1.24-2.01; P = .01). CONCLUSIONS: In a propensity score-matched model, PBTs are independently associated with increased morbidity and mortality in neonates who undergo surgery. Prospective data are needed to better understand the potential effects of a red blood cell transfusion in this patient population.
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Transfusão de Sangue/mortalidade , Complicações Pós-Operatórias/epidemiologia , Cuidados Pré-Operatórios , Procedimentos Cirúrgicos Operatórios/mortalidade , Transfusão de Sangue/estatística & dados numéricos , Comorbidade , Intervalos de Confiança , Bases de Dados Factuais , Transfusão de Eritrócitos/efeitos adversos , Transfusão de Eritrócitos/mortalidade , Transfusão de Eritrócitos/estatística & dados numéricos , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro/sangue , Masculino , Razão de Chances , Complicações Pós-Operatórias/mortalidade , Pontuação de Propensão , Melhoria de Qualidade , Análise de Regressão , Resultado do TratamentoRESUMO
BACKGROUND: Managing pediatric crises necessitates the acquisition of unique skills and confidence in its execution. Our aim was to develop and assess a curriculum based on the constructivist learning environment to enhance learning, orientation, and preparation of graduating pediatric anesthesiology fellows. METHODS: Fifty pediatric anesthesiology fellows from 9 academic institutions in the United States were recruited for an advanced boot camp over a 2-year period. Training stations were developed using high-fidelity simulation, standardized patients, self-reflection modules, and facilitated discussions. The curriculum was evaluated using an anonymous survey that assessed knowledge, self-confidence, appropriateness of case-scenario complexity, and usefulness for transitioning into an independent practitioner on a Likert scale (1 = strongly disagree to 5 = strongly agree). Data points were expressed as the median and interquartile range (IQR). RESULTS: Ninety-eight percent of the fellows completed a survey. Fellow perceptions of the advanced boot camp was positive. The median scores (IQR) for knowledge, self-confidence, appropriateness of case complexity, and usefulness for transition in 2017 were 5 (3,5), 4.5 (3,5), 5 (3,5), and 5 (3,5), respectively, and 5 (3,5), 4.5 (3,5), 5 (4,5), and 5 (3,5), respectively, in 2018. The IQR in the assessment for an appropriate level of complexity for their level of training, narrowed in 2018 (4,5), when compared with 2017 (3,5). CONCLUSIONS: Fellow responses support the idea that the advanced boot camp provided tools and strategies for their transition. A narrowed IQR regarding the appropriate level of complexity of scenarios in 2018, when compared with 2017, might suggest an improvement in the curriculum.
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Attempts to directly drug the important oncogene KRAS have met with limited success despite numerous efforts across industry and academia. The KRASG12C mutant represents an "Achilles heel" and has recently yielded to covalent targeting with small molecules that bind the mutant cysteine and create an allosteric pocket on GDP-bound RAS, locking it in an inactive state. A weak inhibitor at this site was optimized through conformational locking of a piperazine-quinazoline motif and linker modification. Subsequent introduction of a key methyl group to the piperazine resulted in enhancements in potency, permeability, clearance, and reactivity, leading to identification of a potent KRASG12C inhibitor with high selectivity and excellent cross-species pharmacokinetic parameters and in vivo efficacy.
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Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Piperazinas/uso terapêutico , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Quinazolinas/uso terapêutico , Quinolonas/uso terapêutico , Regulação Alostérica , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacocinética , Células CACO-2 , Linhagem Celular Tumoral , Desenho de Fármacos , Humanos , Masculino , Camundongos Nus , Conformação Molecular , Mutação , Piperazinas/síntese química , Piperazinas/farmacocinética , Proteínas Proto-Oncogênicas p21(ras)/genética , Quinazolinas/síntese química , Quinazolinas/farmacocinética , Quinolonas/síntese química , Quinolonas/farmacocinética , Ratos Wistar , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Introduction: KRAS is one of the most important oncology drug targets, playing a pivotal role in the initiation and progression of many human tumors. It has long been held undruggable due to many previously failed attempts to both directly and indirectly target this challenging GTPase protein family.Areas covered: This review covers patent applications claiming inhibitors of the mutant GTPase KRASG12C that act via covalent modification of cysteine at codon 12 in the period of 2014 to the present. A total of 37 PCT applications from 9 applicants are evaluated, with the discussion organized alphabetically by assignee name.Expert opinion: The last 5 years have seen an explosion in interest around this important target with many companies aiming to capitalize on the breakthrough discovery of covalent allosteric inhibitors of the glycine to cysteine mutant form of the enzyme. The first agents from this effort have now entered clinical trials and preliminary data are encouraging with responses seen in both lung adenocarcinoma and colorectal cancer patients.
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Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Animais , Progressão da Doença , Descoberta de Drogas , Humanos , Terapia de Alvo Molecular , Neoplasias/patologia , Patentes como AssuntoRESUMO
BACKGROUND: Direct-acting antivirals (DAA) have revolutionised hepatitis C virus (HCV) treatment, and most regimens include an NS5A inhibitor. Certain amino-acid substitutions confer resistance to NS5A inhibitors, termed resistance-associated substitutions (RAS). If present at baseline, they can reduce virological response rates. Population-based sequencing (PBS) is generally used for baseline sequencing, however next generation sequencing (NGS) reduces the threshold for detection of sequences encoding RAS from 20% to 5%. We determined the prevalence of NS5A RAS at baseline amongst Australian chronically infected with genotype (GT)1a, GT1b and GT3 HCV, using both PBS and NGS. METHODS: Samples from DAA-naïve individuals were received at the Victorian Infectious Disease Reference Laboratory between June 2016 and December 2018. All samples were analysed for NS5A RAS using PBS. A subset of GT1 HCV samples were processed using NGS technology (Vela Diagnostics, Singapore) to determine the improvement in sensitivity. RESULTS: In total, 672 samples were analysed using PBS. The baseline prevalence of NS5A RAS was 7.6% for GT1a (n = 25/329), 15.7% for GT1b (n = 8/51) and 15.1% for GT3 (n = 44/292). NGS only marginally increased sensitivity for NS5A RAS at baseline in GT1a (16% vs 17%) and GT1b (29% vs 36%). CONCLUSION: The prevalence of NS5A RAS in GT1a HCV in Australia was low compared with international data, and was similar to other reported international prevalence for GT1b and GT3 infection. NGS at baseline only marginally increased sensitivity for the detection of NS5A RAS in patients with GT1 HCV and cannot be recommended for routine use at baseline in clinical practice.
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Farmacorresistência Viral , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Proteínas não Estruturais Virais/genética , Substituição de Aminoácidos , Austrália/epidemiologia , Feminino , Genótipo , Hepatite C Crônica/virologia , Humanos , Masculino , Prevalência , RNA Viral/genética , Análise de Sequência de RNARESUMO
BACKGROUND: In Australia, Hepatitis C Virus (HCV) treatment is declining, despite broad access to direct-acting antiviral medication. People who inject drugs are proportionally over-represented in emergency department presentations. Emergency department assessment of people who have injected drugs for HCV presents an opportunity to engage this marginalised population with treatment. We describe the outcomes of risk-based screening and point-of-care anti-HCV testing for emergency department patients, and linkage to outpatient antiviral treatment. METHODS: During the three-month study period, consecutive adult patients who presented to the emergency department during the study times were screened for risk factors and offered the OraQuick oral HCV antibody test. Those with reactive results were offered venepuncture in the emergency department for confirmatory testing and direct-acting antiviral treatment in clinic. The main outcome measures were the number and proportion of viremic participants that were linked to the hepatitis clinic, commenced treatment and achieved a sustained viral response. Secondary outcome measures were the proportion (%) of presentations screened that were oral antibody reactive, and the prevalence and type of HCV risk factors. RESULTS: During the study period, 2408 of the 3931 (61%) presentations to the emergency department were eligible for screening. Of these 2408 patients, 1122 (47%) participated, 307 (13%) declined participation and 977 (41%) could not be approached during their time in the emergency department. Among the 1122 participants, 378 (34%) reported at least one risk factor. Subsequently, 368 (97%) of the 378 participants underwent OraQuick anti-HCV test, and 50 (14%) had a reactive result. A risk factor of ever having injected drugs was present in 44 (88%) of participants who were sero-positive. Of the 45 that had blood tested, 30 (67%) were HCV ribonucleic acid (RNA) positive. Three participants died. Of the 27 remaining participants, 10 (37%) commenced treatment and 7 of these 10 (70%) obtained a cure. There was a high rate of homelessness (24%) among anti-HCV positive participants. CONCLUSION: Among emergency department participants with a risk factor for HCV, positive serology was common using a rapid point-of-care test. A history of injecting drug use was identified as the risk factor with highest yield for positive HCV serology, and is suitable as a single screening question. However, linkage to care post ED presentation was low in this marginalised population. There is a need for new pathways to improve the care cascade for marginalised individuals living with HCV infection.