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Isoquinolone is one of the most common heterocyclic core structures in countless natural products and many bioactive compounds. Here, a highly efficient approach to synthesize isoquinolone scaffolds on DNA via rhodium(III)-catalyzed C-H activation has been described. This chemistry transformation is robust and has shown good compatibility with DNA, which is suitable for DNA-encoded library synthesis.
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ADN , Rodio , Rodio/química , Catálisis , Estructura Molecular , ADN/química , Isoquinolinas/química , Isoquinolinas/síntesis químicaRESUMEN
2- or 4-Pyridyl benzylic amines represent a privileged motif in drug discovery. However, the formation of heterocyclic benzylic amines with fully substituted α-carbons can require the execution of lengthy synthetic routes, which limit their application. Addition of various nucleophilic agents to Ellman's imines has been well established; however, there is no precedented literature reported for pyridyl-type nucleophiles, which are very important for medicinal chemistry. In this letter, we disclose the development of a one-step synthesis of heterocyclic benzylic amines with fully substituted α-carbons from heteroaryl halides and sulfinyl imines. Starting from 2,4-dibromopyridine, regioselective synthesis of 2- or 4-pyridyl benzylic amines could be achieved by choosing toluene or MTBE as a solvent.
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In this study, we systematically evaluate different ambiphilic organohalides for their ability to participate in anti-selective carbo- or heteroannulation with non-conjugated alkenyl amides under PdII /PdIV catalysis. Detailed optimization of the reaction conditions has led to protocols for synthesizing tetrahydropyridines, tetralins, pyrrolidines, and other carbo/heterocyclic cores via [n+2] (n=3-5) (hetero)annulation. Expansion of scope to otherwise unreactive ambiphilic haloketones through PdII /amine co-catalysis is also demonstrated. Compared to other annulation processes, this method proceeds via a distinct PdII /PdIV mechanism involving Wacker-type directed nucleopalladation. This difference results in unique reactivity and selectivity patterns, as revealed through assessment of reaction scope and competition experiments.
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Alquenos , Paladio , Catálisis , PirrolidinasRESUMEN
Protein arginine methyltransferase 5 (PRMT5) overexpression in hematologic and solid tumors methylates arginine residues on cellular proteins involved in important cancer functions including cell-cycle regulation, mRNA splicing, cell differentiation, cell signaling, and apoptosis. PRMT5 methyltransferase function has been linked with high rates of tumor cell proliferation and decreased overall survival, and PRMT5 inhibitors are currently being explored as an approach for targeting cancer-specific dependencies due to PRMT5 catalytic function. Here, we describe the discovery of potent and selective S-adenosylmethionine (SAM) competitive PRMT5 inhibitors, with in vitro and in vivo characterization of clinical candidate PF-06939999. Acquired resistance mechanisms were explored through the development of drug resistant cell lines. Our data highlight compound-specific resistance mutations in the PRMT5 enzyme that demonstrate structural constraints in the cofactor binding site that prevent emergence of complete resistance to SAM site inhibitors. PRMT5 inhibition by PF-06939999 treatment reduced proliferation of non-small cell lung cancer (NSCLC) cells, with dose-dependent decreases in symmetric dimethyl arginine (SDMA) levels and changes in alternative splicing of numerous pre-mRNAs. Drug sensitivity to PF-06939999 in NSCLC cells associates with cancer pathways including MYC, cell cycle and spliceosome, and with mutations in splicing factors such as RBM10. Translation of efficacy in mouse tumor xenograft models with splicing mutations provides rationale for therapeutic use of PF-06939999 in the treatment of splicing dysregulated NSCLC.
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Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Proteína-Arginina N-Metiltransferasas/antagonistas & inhibidores , S-Adenosilmetionina/metabolismo , Animales , Apoptosis , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Proliferación Celular , Resistencia a Medicamentos , Femenino , Humanos , Neoplasias Pulmonares/patología , RatonesRESUMEN
2,3-Dihydrobenzofurans and indolines are common substructures in medicines and natural products. Herein, we describe a method that enables direct access to these core structures from non-conjugated alkenyl amides and ortho-iodoanilines/phenols. Under palladium(II) catalysis this [3 + 2] heteroannulation proceeds in an anti-selective fashion and tolerates a wide variety of functional groups. N-Acetyl, -tosyl, and -alkyl substituted ortho-iodoanilines, as well as free -NH2 variants, are all effective. Preliminary results with carbon-based coupling partners also demonstrate the viability of forming indane core structures using this approach. Experimental and computational studies on reactions with phenols support a mechanism involving turnover-limiting, endergonic directed oxypalladation, followed by intramolecular oxidative addition and reductive elimination.
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Alquenos/química , Paladio/química , Compuestos de Anilina/química , Simulación por Computador , Fenoles/química , TermodinámicaRESUMEN
INTRODUCTION: There have been very few randomized clinical trials of interventions for alcohol use disorders (AUD) in people living with HIV (PLWH) in African countries. This is despite the fact that alcohol use is one of the modifiable risk factors for poor virological control in PLWH on antiretroviral therapy. METHODS: Sixteen clinic clusters in Zimbabwe were selected through stratified randomization and randomized 1: 1 to Intervention and Control arms. Inclusion criteria for individual participants were being adult, living with HIV and a probable alcohol use disorder as defined by a score of 6 (women) or 7 (men) on the Alcohol Use Disorders Identification Test (AUDIT). In the Intervention clusters, participants received 8 to 10 sessions of Motivational Interviewing blended with brief Cognitive Behavioural Therapy (MI-CBT). In the control clusters, participants received four Enhanced Usual Care (EUC) sessions based on the alcohol treatment module from the World Health Organisation mhGAP intervention guide. General Nurses from the clinics were trained to deliver both treatments. The primary outcome was a change in AUDIT score at six-month post-randomization. Viral load, functioning and quality of life were secondary outcomes. A random-effects analysis-of-covariance model was used to account for the cluster design. RESULTS: Two hundred and thirty-four participants (n = 108 intervention and n = 126 control) were enrolled across 16 clinics. Participants were recruited from November 2016 to November 2017 and followed through to May 2018. Their mean age was 43.3 years (SD = 9.1) and 78.6% (n = 184) were male. At six months, the mean AUDIT score fell by -6.15 (95% CI -6.32; -6.00) in the MI-CBT arm, compared to a fall of - 3.09 95 % CI - 3.21; -2.93) in the EUC arm (mean difference -3.09 (95% CI -4.53 to -1.23) (p = 0.05). Viral load reduced and quality of life and functioning improved in both arms but the difference between arms was non-significant. CONCLUSIONS: Interventions for hazardous drinking and AUD comprising brief, multiple alcohol treatment sessions delivered by nurses in public HIV facilities in low-income African countries can reduce problematic drinking among PLWH. Such interventions should be integrated into the primary care management of AUD and HIV and delivered by non-specialist providers. Research is needed on cost-effectiveness and implementation of such interventions, and on validation of cut-points for alcohol use scales in low resource settings, in partnership with those with lived experience of HIV and AUD.
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Alcoholismo/terapia , Infecciones por VIH/psicología , Intervención Psicosocial , Adulto , Terapia Cognitivo-Conductual , Femenino , Humanos , Masculino , Persona de Mediana Edad , Entrevista Motivacional , Enfermeras y EnfermerosRESUMEN
Indazoles represent a privileged motif in drug discovery. However, the formation of highly substituted indazoles can require the execution of lengthy synthetic routes with minimal opportunities to introduce diversity. In this report, we disclose the development of a late-stage diversification strategy for the 4- and 5-positions of 4,5,6-trisubstituted indazoles. A regioselective C-H functionalization and subsequent nucleophilic aromatic substitution provide two sequential points of diversification. The synthetic sequence delivers rapid access to an array of 4,5,6-trisubstituted indazoles in only four steps from readily available starting materials.
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Background: The National Patient Safety Agency reported over 20 000 safety incidents over a 3-year period, including 68 severe harms and 27 deaths. Dose delays and omissions persistently contributed to more than 50% of the reported incidents. Methods: A pilot was designed and data were collected before and after to measure how these ward-based technician roles affected the reporting of omitted or delayed doses, time efficiency, cost implications and the general productivity of the ward. Results: Three months after the start of the pilot, omitted doses were reduced from 14% to 5% and no incidents of harm had been reported. The 'perfect medication ward round' with no interruptions lasted 23 min compared with the longest medication ward round which lasted 116 min and was interrupted 11 times. Conclusions: The pilot shows that the introduction of pharmacy technicians results in fewer omitted doses and also addresses persistent staffing issues by ensuring better use of nursing time.
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Errores de Medicación/prevención & control , Grupo de Enfermería/normas , Servicio de Farmacia en Hospital/normas , Técnicos de Farmacia/normas , Rol Profesional , Humanos , Errores de Medicación/tendencias , Grupo de Enfermería/tendencias , Servicio de Farmacia en Hospital/tendencias , Técnicos de Farmacia/tendencias , Proyectos Piloto , Recursos Humanos/normas , Recursos Humanos/tendenciasRESUMEN
BACKGROUND: IV drugs are commonly prescribed for inpatient treatment. Where administered as infusions, drug dose loss is incurred if the infusion line is not flushed. Underdosing of IV antimicrobials is of particular concern as reduced treatment efficacy increases the risk of patient deterioration (including sepsis) and development of antimicrobial resistance. OBJECTIVES: To quantify drug loss, raise awareness and provide recommendations to address this patient safety risk effectively. METHODS: Percentage drug loss of 39 IV antimicrobials was calculated for a theoretical patient case scenario, using residual volumes for IV infusion lines utilized within this acute healthcare setting. An adult male patient (70 kg) with good renal function was assumed for drug dosing. Infusion volumes and doses are based on a widely used IV administration guide. RESULTS: Data revealed the scope and extent of antimicrobial drug losses where infusion lines were not flushed as ranging from 2% to 33%. More than 10% of the drug would be lost for 26 of the 39 antimicrobials assessed, with five of these yielding over 20% loss. CONCLUSIONS: The authors suggest that unintentional antimicrobial underdosing is going unnoticed in clinical practice. Where IV infusion is necessary, flushing of the infusion line to ensure total dose administration is strongly recommended. Risks associated with flushing lines (fluid overloading, bolus dosing, etc.) can be managed with simple measures. The authors call for a national body-led approach to effectively influence healthcare organizations in review of IV administration protocols, ensuring patient safety and care in the NHS.
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Rh-catalyzed C-H functionalization of O-pivaloyl benzhydroxamic acids with propene gas provides access to 4-methyl-substituted dihydroisoquinolones. Good to excellent levels of regioselectivity are achieved using [CptRhCl2]2 as a precatalyst under optimized conditions. Thorough examination of aryl/heteroaryl O-pivaloyl hydroxamic acid substrates, ligand effects on C-H site selectivity, alkene scope, and demonstration of scale are discussed within.
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BACKGROUND: Alcohol use in HIV infected patients is associated with risky sexual behaviour, poor adherence to Highly Active Antiretroviral Therapy, treatment failure and increased physiologic harm. The objectives of the study were to pilot the outcome assessments to be used in the trial proper, assess the feasibility of delivery of a brief MI/CBT intervention compared to an WHO mhGAP intervention for problematic alcohol use in PLWH in Zimbabwe, and pilot the effectiveness (on alcohol use, functionality and CD4 count) of these interventions at 3 months in a randomised controlled trial design. METHODS: An intervention for HIV infected patients with problematic alcohol use, developed through adaptation of existing evidence based psychological treatments, was assessed for its feasibility at a tertiary HIV care clinic in Zimbabwe. Registered general nurses, using a manualised protocol, delivered the intervention. Forty patients were recruited and randomised to receive either an MI/CBT intervention or the WHO mhGAP Intervention Guide for AUDs (n = 20 patients per group). RESULTS: Out of 40 participants enrolled, 31 were successfully followed up for 3 months with a loss to follow-up rate of 23%. There was a statistically significant decrease in AUDIT score over time in both groups (p < 0.001), however no statistically significant group difference with a mean difference of 0.80, standard error of 2.07 and p = 0.70. For the CD4 count, the median and interquartile ranges at baseline for MI/CBT and WHO mhGAP IG groups were 218 (274) and 484 (211.50), respectively. At follow-up, median and interquartile ranges for the CD4 count for MI/CBT and WHO mhGAP IG groups were 390 (280) and 567 (378), respectively, indicative of improvement in immunological parameters in both arms. CONCLUSION: The findings from this pilot study suggests that a brief MI/CBT delivered by Registered General Nurses for problematic alcohol use is feasible in this population but will require the implementation of additional measures to improve retention. However, mechanisms to improve retention need special attention. Trial registration Pan African Clinical Trial Registry, current PACTR201509001211149.
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Trastornos Relacionados con Alcohol/epidemiología , Trastornos Relacionados con Alcohol/terapia , Instituciones de Atención Ambulatoria/organización & administración , Infecciones por VIH/epidemiología , Psicoterapia/métodos , Adulto , Terapia Antirretroviral Altamente Activa/métodos , Recuento de Linfocito CD4 , Terapia Cognitivo-Conductual/métodos , Estudios de Factibilidad , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Entrevista Motivacional/métodos , Enfermeras y Enfermeros/organización & administración , Proyectos Piloto , Psicoterapia Breve , Calidad de Vida , Conducta Sexual , Factores Socioeconómicos , Carga Viral , ZimbabweRESUMEN
The copper-catalyzed hydroboration of benzylidenecyclopropanes, conveniently accessed in one step from readily available benzaldehydes, is reported. Under otherwise identical reaction conditions, two distinct phosphine ligands grant access to different products by either suppressing or promoting cyclopropane opening via ß-carbon elimination. Computational studies provide insight into how the rigidity and steric environment of these different bis-phosphine ligands influence the relative activation energies of ß-carbon elimination versus protodecupration from the key benzylcopper intermediate. The method tolerates a wide variety of heterocycles prevalent in clinical and pre-clinical drug development, giving access to valuable synthetic intermediates. The versatility of the tertiary cyclopropylboronic ester products is demonstrated through several derivatization reactions.
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Hormones of the neurotrophin family, nerve growth factor (NGF), brain derived neurotrophic factor (BDNF), neurotrophin 3 (NT3), and neurotrophin 4 (NT4), are known to activate the family of Tropomyosin receptor kinases (TrkA, TrkB, and TrkC). Moreover, inhibition of the TrkA kinase pathway in pain has been clinically validated by the NGF antibody tanezumab, leading to significant interest in the development of small molecule inhibitors of TrkA. Furthermore, Trk inhibitors having an acceptable safety profile will require minimal brain availability. Herein, we discuss the discovery of two potent, selective, peripherally restricted, efficacious, and well-tolerated series of pan-Trk inhibitors which successfully delivered three candidate quality compounds 10b, 13b, and 19. All three compounds are predicted to possess low metabolic clearance in human that does not proceed via aldehyde oxidase-catalyzed reactions, thus addressing the potential clearance prediction liability associated with our current pan-Trk development candidate PF-06273340.
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Descubrimiento de Drogas , Dolor/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Animales , Humanos , Ligandos , Simulación del Acoplamiento Molecular , Conformación Proteica , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacocinética , Inhibidores de Proteínas Quinasas/uso terapéutico , Piridinas/química , Piridinas/farmacocinética , Piridinas/farmacología , Piridinas/uso terapéutico , Ratas , Proteínas Tirosina Quinasas Receptoras/química , Proteínas Tirosina Quinasas Receptoras/metabolismo , Solubilidad , Relación Estructura-Actividad , Distribución TisularRESUMEN
BACKGROUND: Alcohol use is associated with poor HIV treatment outcomes. This study aimed to understand patients' perceptions of the impact of alcohol use in the context of HIV care. METHODS: The study design was a descriptive qualitative study of HIV positive individuals receiving antiretroviral treatment. The study involved four focus group discussions with male and female participants at a tertiary center, city clinic, and rural church. We employed convenience sampling and invited patients coming for their routine visits and medication refills to participate. RESULTS: Participants had an awareness of both the direct and indirect effects of alcohol use. The direct effects related to the incompatibility of HIV medication and alcohol. The indirect effects related to the negative impact of alcohol on treatment adherence. Participants proffered reasons why HIV infected individuals on HIV treatment drink and felt that patients had to make a deliberate choice to stop drinking. Participants displayed some knowledge of interventions for drinking cessation and highlighted the use of pharmacological interventions to stop drinking. Participants indicated that they preferred HIV counselors to provide counseling services in view of the existing relationships that patients had with counselors. CONCLUSION: People living with HIV have adequate knowledge of the effects of alcohol use in the context of HIV treatment. Stigma and the time taken to engage in an alcohol use intervention appeared to be the main impediments to uptake. The current model of HIV treatment, based on trust with the HIV care team, and maintenance of this trust, could bolster the uptake of an intervention. Involvement of HIV patients in their treatment is necessary to improve treatment outcomes in the context of alcohol use.
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Small molecules containing cyclopropane-heteroatom linkages are commonly needed in medicinal chemistry campaigns yet are problematic to prepare using existing methods. To address this issue, a scalable Chan-Lam cyclopropylation reaction using potassium cyclopropyl trifluoroborate has been developed. With phenol nucleophiles, the reaction effects O-cyclopropylation, whereas with 2-pyridones, 2-hydroxybenzimidazoles, and 2-aminopyridines the reaction brings about N-cyclopropylation. The transformation is catalyzed by Cu(OAc)2 and 1,10-phenanthroline and employs 1 atm of O2 as the terminal oxidant. This method is operationally convenient to perform and provides a simple, strategic disconnection toward the synthesis of cyclopropyl aryl ethers and cyclopropyl amine derivatives bearing an array of functional groups.
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Compuestos Aza/química , Cobre/química , Ciclopropanos/síntesis química , Compuestos Heterocíclicos/química , Fenoles/química , Catálisis , Ciclopropanos/química , Estructura MolecularRESUMEN
BACKGROUND: Interventions for alcohol use disorders (AUDs) in HIV infected individuals have been primarily targeted at HIV risk reduction and improved antiretroviral treatment adherence. However, reduction in alcohol use is an important goal. Alcohol use affects other key factors that may influence treatment course and outcome. In this study the authors aim to administer an adapted intervention for AUDs to reduce alcohol use in people living with HIV/AIDS (PLWHA). METHODS: This study is a cluster randomised controlled trial at 16 HIV care clinics. A motivational interviewing and cognitive behavioural therapy based intervention for AUDs, developed through adaptation and piloted in Zimbabwe, will be administered to PLWHA with AUDs recruited at HIV clinics. The intervention will be administered over 16 sessions at 8 HIV clinics. This intervention will be compared with an equal attention control in the form of the World Health Organization Mental Health Gap Action Programme (WHO mhGAP) guide, adapted for the Zimbabwean context. General function, quality of life, and adherence to highly active antiretroviral treatment (HAART) will be secondary outcomes. Booster sessions will be administered to both groups at 3 and 6 months respectively. The primary outcome measure will be the Alcohol Use Disorder Identification Test (AUDIT) score. The World Health Organisation Disability Assessment Schedule 2.0 (WHODAS 2.0), World Health Organisation Quality of Life (WHOQoL) HIV, viral load, and CD4 counts will be secondary outcome measures. Outcome assessments will be administered at baseline, 3, 6, and 12 months. Moderating factors such as perceived social support, how people cope with difficult situations and post-traumatic exposure and experience will be assessed at baseline. Trained research assistants will recruit participants. The outcome assessors who will be trained in administering the outcome and moderating tools will be blinded to the treatment arms allocated to the participants. However, the principal investigator, participants and intervention staff will be unblinded. Data will be analysed using STATA Version 14. Primary and secondary outcomes will be measured at four time points that is; at baseline, 3, 6, and 12 months respectively. All participants will be included in the analysis of primary and secondary outcome measures. The mean AUDIT scores will be compared between groups using student t-tests. Multilevel logistic regression analysis will be performed for binominal variables and multilevel linear regression for continuous variables. Descriptive statistics will be computed for baseline and follow-up assessments. DISCUSSION: The study will be the first to address problematic alcohol use in PLWHA in Zimbabwe. It seeks to use local resources in delivering a modified, brief, evidence-based, and culturally contextualised intervention. The study results will determine the effectiveness of adapting psychological interventions for AUDs in HIV infected adults using a task-sharing framework. TRIAL REGISTRATION: Pan African Clinical Trial Registry, PACTR201509001211149 . Registered 22 July 2015.
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Síndrome de Inmunodeficiencia Adquirida/terapia , Trastornos Relacionados con Alcohol/terapia , Terapia Antirretroviral Altamente Activa , Infecciones por VIH/terapia , Cumplimiento de la Medicación , Calidad de Vida , Síndrome de Inmunodeficiencia Adquirida/epidemiología , Síndrome de Inmunodeficiencia Adquirida/psicología , Actividades Cotidianas/psicología , Adulto , Consumo de Bebidas Alcohólicas/epidemiología , Consumo de Bebidas Alcohólicas/psicología , Consumo de Bebidas Alcohólicas/terapia , Trastornos Relacionados con Alcohol/epidemiología , Trastornos Relacionados con Alcohol/psicología , Terapia Antirretroviral Altamente Activa/psicología , Análisis por Conglomerados , Terapia Cognitivo-Conductual/métodos , Intervención Médica Temprana/métodos , Femenino , Estudios de Seguimiento , Infecciones por VIH/epidemiología , Infecciones por VIH/psicología , Humanos , Masculino , Cumplimiento de la Medicación/psicología , Proyectos Piloto , Calidad de Vida/psicología , Zimbabwe/epidemiologíaRESUMEN
Here, we report accessing small 3-fluoropyrrolidines and 3,3-difluoropyrrolidines through a 1,3-dipolar cycloaddition with a simple azomethine ylide and a variety of vinyl fluorides and vinyl difluorides. We demonstrate that vinyl fluorides within α,ß-unsaturated, styrenyl and even enol ether systems can participate in the cycloaddition reaction. The vinyl fluorides are relatively easy to synthesize through a variety of methods, making the 3-fluoropyrrolidines very accessible.
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Compuestos Azo/química , Pirrolidinas/síntesis química , Tiosemicarbazonas/química , Reacción de Cicloadición , Estructura Molecular , Pirrolidinas/química , EstereoisomerismoRESUMEN
BACKGROUND: The use of simulated patients to teach in psychiatry has not been reported from low-income countries. This is the first study using simulation teaching in psychiatry in Africa. The aim of this study was to introduce a novel method of psychiatric teaching to medical students at the University of Zimbabwe and assess its feasibility and preliminary effectiveness. We selected depression to simulate because students in Zimbabwe are most likely to see cases of psychoses during their ward-based clinical exposure. METHODS: Zimbabwean psychiatrists adapted scenarios on depression and suicide based on ones used in London. Zimbabwean post-graduate trainee psychiatrists were invited to carry out the teaching and psychiatric nursing staff were recruited and trained in one hour to play the simulated patients (SPs). All students undertaking their psychiatry placement (n = 30) were allocated into groups for a short didactic lecture on assessing for clinical depression and then rotated around 3 scenarios in groups of 4-5 and asked to interview a simulated patient with signs of depression. Students received feedback from peers, SPs and facilitators. Students completed the Confidence in Assessing and Managing Depression (CAM-D) questionnaire before and after the simulation session and provided written free-text feedback. RESULTS: Post-graduate trainers, together with one consultant, facilitated the simulated teaching after three hours training. Student confidence scores increased from mean 15.90 to 20.05 (95% CI = 2.58- 5.71) t (20) = 5.52, (p > 0.0001) following the simulation teaching session. Free-text feedback was positive overall with students commenting that it was "helpful", "enjoyable" and "boosted confidence". CONCLUSIONS: In Zimbabwe, simulation teaching was acceptable and could be adapted with minimal effort by local psychiatrists and implemented by post-graduate trainees and one consultant, Students found it helpful and enjoyable and their confidence increased after the teaching. It offers students a broader exposure to psychiatric conditions than they receive during clinical attachment to the inpatient wards. Involving psychiatry trainees and nursing staff may be a sustainable approach in a setting with small number of consultants and limited funds to pay for professional actors.
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Educación de Pregrado en Medicina , Simulación de Paciente , Aprendizaje Basado en Problemas/organización & administración , Psiquiatría/educación , Adulto , Competencia Clínica , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/psicología , Trastorno Depresivo/terapia , Estudios de Factibilidad , Femenino , Retroalimentación Formativa , Humanos , Masculino , Autoeficacia , Adulto Joven , ZimbabweRESUMEN
The hepatocyte growth factor (HGF)/c-Met signaling axis is deregulated in many cancers and plays important roles in tumor invasive growth and metastasis. An exclusively selective c-Met inhibitor (S)-6-(1-(6-(1-methyl-1H-pyrazol-4-yl)-[1,2,4]triazolo[4,3-b]pyridazin-3-yl)ethyl)quinoline (8) was discovered from a highly selective high-throughput screening hit via structure-based drug design and medicinal chemistry lead optimization. Compound 8 had many attractive properties meriting preclinical evaluation. Broad off-target screens identified 8 as a pan-phosphodiesterase (PDE) family inhibitor, which was implicated in a sustained increase in heart rate, increased cardiac output, and decreased contractility indices, as well as myocardial degeneration in in vivo safety evaluations in rats. Compound 8 was terminated as a preclinical candidate because of a narrow therapeutic window in cardio-related safety. The learning from multiparameter lead optimization and strategies to avoid the toxicity attrition at the late stage of drug discovery are discussed.
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Cardiomiopatías/enzimología , Inhibidores de Fosfodiesterasa/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Quinolinas/farmacología , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Animales , Femenino , Humanos , Ratones , Ratones Desnudos , Modelos Moleculares , Inhibidores de Fosfodiesterasa/química , Inhibidores de Proteínas Quinasas/química , Quinolinas/química , Ratas , Proteínas Tirosina Quinasas Receptoras/químicaRESUMEN
The c-MET receptor tyrosine kinase is an attractive oncology target because of its critical role in human oncogenesis and tumor progression. An oxindole hydrazide hit 6 was identified during a c-MET HTS campaign and subsequently demonstrated to have an unusual degree of selectivity against a broad array of other kinases. The cocrystal structure of the related oxindole hydrazide c-MET inhibitor 10 with a nonphosphorylated c-MET kinase domain revealed a unique binding mode associated with the exquisite selectivity profile. The chemically labile oxindole hydrazide scaffold was replaced with a chemically and metabolically stable triazolopyrazine scaffold using structure based drug design. Medicinal chemistry lead optimization produced 2-(4-(1-(quinolin-6-ylmethyl)-1H-[1,2,3]triazolo[4,5-b]pyrazin-6-yl)-1H-pyrazol-1-yl)ethanol (2, PF-04217903), an extremely potent and exquisitely selective c-MET inhibitor. 2 demonstrated effective tumor growth inhibition in c-MET dependent tumor models with good oral PK properties and an acceptable safety profile in preclinical studies. 2 progressed to clinical evaluation in a Phase I oncology setting.