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1.
BMC Nephrol ; 25(1): 45, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38297189

RESUMO

BACKGROUND: Individuals with chronic kidney disease experience difficult physical and psychological symptoms, that impact quality of life, and are at increased risk of anxiety and depression. Access to specialist psychological support is limited. This study aimed to support a new service development project, in collaboration with Kidney Care UK, to implement the Compassionate Mindful Resilience (CMR) programme, developed by MindfulnessUK, which provides accessible mindfulness techniques and practices to enhance compassion and resilience, and explore its feasibility for people living with stage 4 or 5 kidney disease and transplant. METHODS: A multi-method feasibility design was utilised. Participants over 18 years, from the UK, with stage 4 or 5 kidney disease or post-transplant, and who were not currently undergoing psychotherapy, were recruited to the four-week CMR programme. Data was collected at baseline, post-intervention and three-months post to measure anxiety, depression, self-compassion, mental wellbeing, resilience, and mindfulness. The acceptability of the intervention for a kidney disease population was explored through qualitative interviews with participants, and the Mindfulness Teacher. RESULTS: In total, 75 participants were recruited to the study, with 65 completing the CMR programme. The majority were female (66.2%) and post-transplant (63.1%). Analysis of completed outcome measures at baseline and post-intervention timepoints (n = 61), and three-months post intervention (n = 45) revealed significant improvements in participant's levels of anxiety (p < .001) and depression (p < .001), self-compassion (p = .005), mental wellbeing (p < .001), resilience (p.001), and mindfulness (p < .001). Thematic analysis of interviews with participants (n = 19) and Mindfulness Teacher (n = 1) generated three themes (and nine-subthemes); experiences of the CMR programme that facilitated subjective benefit, participants lived and shared experiences, and practicalities of programme participation. All participants interviewed reported that they found programme participation to be beneficial. CONCLUSION: The findings suggest that the CMR programme has the potential to improve psychological outcomes among people with chronic kidney disease. Future randomized controlled trials are required to further test its effectiveness.


Assuntos
Atenção Plena , Insuficiência Renal Crônica , Resiliência Psicológica , Adulto , Feminino , Humanos , Masculino , Empatia , Estudos de Viabilidade , Atenção Plena/métodos , Qualidade de Vida , Insuficiência Renal Crônica/psicologia , Insuficiência Renal Crônica/terapia
2.
Br J Sports Med ; 57(8): 441-449, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36754590

RESUMO

Using an expert consensus-based approach, a netball video analysis consensus (NVAC) group of researchers and practitioners was formed to develop a video analysis framework of descriptors and definitions of physical, technical and contextual aspects for netball research. The framework aims to improve the consistency of language used within netball investigations. It also aims to guide injury mechanism reporting and identification of injury risk factors. The development of the framework involved a systematic review of the literature and a Delphi process. In conjunction with commercially used descriptors and definitions, 19 studies were used to create the initial framework of key descriptors and definitions in netball. In a two round Delphi method consensus, each expert rated their level of agreement with each of the descriptors and associated definition on a 5-point Likert scale (1-strongly disagree; 2-somewhat disagree; 3-neither agree nor disagree; 4-somewhat agree; 5-strongly agree). The median (IQR) rating of agreement was 5.0 (0.0), 5.0 (0.0) and 5.0 (0.0) for physical, technical and contextual aspects, respectively. The NVAC group recommends usage of the framework when conducting video analysis research in netball. The use of descriptors and definitions will be determined by the nature of the work and can be combined to incorporate further movements and actions used in netball. The framework can be linked with additional data, such as injury surveillance and microtechnology data.


Assuntos
Basquetebol , Humanos , Consenso , Movimento , Técnica Delphi
3.
Am J Physiol Endocrinol Metab ; 320(4): E797-E807, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33645253

RESUMO

Application of glucose clamp methodologies in multicenter studies brings challenges for standardization. The Restoring Insulin Secretion (RISE) Consortium implemented a hyperglycemic clamp protocol across seven centers using a combination of technical and management approaches to achieve standardization. Two-stage hyperglycemic clamps with glucose targets of 200 mg/dL and >450 mg/dL were performed utilizing a centralized spreadsheet-based algorithm that guided dextrose infusion rates using bedside plasma glucose measurements. Clamp operators received initial and repeated training with ongoing feedback based on surveillance of clamp performance. The precision and accuracy of the achieved stage-specific glucose targets were evaluated, including differences by study center. We also evaluated robustness of the method to baseline physiologic differences and on-study treatment effects. The RISE approach produced high overall precision (3%-9% variance in achieved plasma glucose from target at various times across the procedure) and accuracy (SD < 10% overall). Statistically significant but numerically small differences in achieved target glucose concentrations were observed across study centers, within the magnitude of the observed technical variability. Variation of the achieved target glucose over time in placebo-treated individuals was low (<3% variation), and the method was robust to differences in baseline physiology (youth vs. adult, IGT vs. diabetes status) and differences in physiology induced by study treatments. The RISE approach to standardization of the hyperglycemic clamp methodology across multiple study centers produced technically excellent standardization of achieved glucose concentrations. This approach provides a reliable method for implementing glucose clamp methodology across multiple study centers.NEW & NOTEWORTHY The Restoring Insulin Secretion (RISE) study centers undertook hyperglycemic clamps using a simplified methodology and a decision guidance algorithm implemented in an easy-to-use spreadsheet. This approach, combined with active management including ongoing central data surveillance and routine feedback to study centers, produced technically excellent standardization of achieved glucose concentrations on repeat studies within and across study centers.


Assuntos
Glicemia/metabolismo , Técnica Clamp de Glucose/normas , Adolescente , Adulto , Algoritmos , Glicemia/análise , Criança , Diabetes Mellitus Tipo 2/sangue , Feminino , Glucose/administração & dosagem , Glucose/farmacologia , Técnica Clamp de Glucose/métodos , Teste de Tolerância a Glucose/métodos , Teste de Tolerância a Glucose/normas , Humanos , Hiperglicemia/sangue , Hiperglicemia/induzido quimicamente , Secreção de Insulina/efeitos dos fármacos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
4.
BMC Nurs ; 20(1): 253, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930234

RESUMO

BACKGROUND: Mindfulness can potentially positively impact well-being and resilience in undergraduate nursing students. The psychological well-being of such students undertaking clinical training is paramount to ensure optimal learning, and to equip them with skills to manage their wellbeing in future clinical practice. The aim of our study was to explore the views of undergraduate nursing students in relation to understanding and engaging with mindfulness, and how mindfulness could best be delivered within their university programme. METHODS: An online survey was administered via a cloud-based student response system to a convenience sample of first year undergraduate nursing students completing a Bachelor of Science (BSc) Honours (Hons) degree in nursing at a University in the United Kingdom. Data were analysed using descriptive statistics and thematic analysis. RESULTS: The survey achieved a response rate of 78% (n = 208). Seventy-nine percent of participants had heard of mindfulness and were interested in taking part in a mindfulness programme. Respondents reported that the ideal delivery of the programme would consist of weekly 45-min, in person group sessions, over a 6-week period. Respondents also indicated that a mobile application could potentially facilitate participation in the programme. Thematic analysis of open-ended comments, and free text, within the survey indicated 4 overarching themes: 1) Perceptions of what mindfulness is; 2) Previous mindfulness practice experiences; 3) Impact of mindfulness in nursing; 4) The need for a future well-being initiative for undergraduate nursing students. CONCLUSIONS: Undergraduate nursing students perceived that a mindfulness programme has the potential to enhance well-being and future clinical practice. This student cohort are familiar with mindfulness and want more integrated within their undergraduate curriculum. Further research is required to examine the effectiveness of a tailored mindfulness intervention for this population that incorporates the use of both face-to-face and mobile delivery.

5.
Drug Metab Dispos ; 47(5): 484-492, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30787098

RESUMO

The accurate prediction of human pharmacokinetics is critically important in modern drug discovery since it drives both pharmacological and toxicological effects. Although significant progress has been made in predicting drug disposition by hepatic drug-metabolizing enzymes, predicting transporter-mediated clearance is still highly uncertain. Furthermore, different approaches are often used to predict clearance with and without transporter involvement, hence the major clearance pathway for a compound must first be determined to know which approach to use. As a result of these challenges, a novel unified method has been developed using cryopreserved suspended human hepatocytes to predict human hepatic clearance for both enzyme- and transporter-mediated mechanisms. This method hypothesizes that, once in vitro metabolic stability is scaled by partition coefficients between hepatocytes and buffer with 4% bovine serum albumin, in vivo clearance can be better predicted. With this method, good in vitro-in vivo correlation of human hepatic clearance has been obtained for a set of 32 structurally diverse compounds, including such transporters as organic anion-transporting polypeptide substrates. The clearance predictions for most compounds are within 3-fold of observed values. This is the first time that multiple compounds result in good in vitro-in vivo extrapolation using an entirely "bottom-up" approach without any empirical scaling factor when transporter-mediated clearance is involved. Potential exceptions are compounds with significant biliary and/or extra-hepatic clearance. The method offers an alternative approach to more accurately predict human hepatic clearance when multiple complex mechanisms are involved.


Assuntos
Hepatócitos/metabolismo , Fígado/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Taxa de Depuração Metabólica/fisiologia , Transporte Biológico/fisiologia , Humanos , Cinética , Transportadores de Ânions Orgânicos/metabolismo
6.
Xenobiotica ; 49(12): 1447-1457, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30747552

RESUMO

1. The absorption, metabolism, and excretion of a single oral 450-mg dose of [14C]-(S)-6-(3-cyclopentyl-2-(4-trifluoromethyl)-1H-imidazol-1-yl)propanamido)nicotinic acid (PF-04991532), a hepatoselective glucokinase activator, was investigated in humans. Mass balance was achieved with ∼94.6% of the administered dose recovered in urine and feces. The total administered radioactivity excreted in feces and urine was 70.6% and 24.1%, respectively. Unchanged PF-04991532 collectively accounted for ∼47.2% of the dose excreted in feces and urine, suggestive of moderate metabolic elimination in humans. 2. The biotransformation pathways involved acyl glucuronidation (M1), amide bond hydrolysis (M3), and CYP3A4-mediated oxidative metabolism on the cyclopentyl ring in PF-04991532 yielding monohydroxylated isomers (M2a-d). Unchanged PF-04991532 was the major circulating component (64.4% of total radioactivity) whereas M2a-d collectively represented 28.9% of the total plasma radioactivity. 3. Metabolites M2a-d were not detected systemically in rats and dogs, the preclinical species for the toxicological evaluation of PF-04991532. In contrast, cynomologus monkeys dosed orally with unlabeled PF-04991532 revealed M2a-d in circulation, whose UV abundance was comparable to the profile in humans. This observation suggested that monkeys could potentially serve as a non-rodent alternative for studying the toxicity of PF-04991532 and its metabolites M2a-d. 4. The present results are in excellent agreement with our previously generated metabolite scouting data, which provided preliminary evidence for the disproportionate metabolism of PF-04991532 in humans.


Assuntos
Imidazóis/farmacocinética , Ácidos Nicotínicos/farmacocinética , Adolescente , Adulto , Animais , Radioisótopos de Carbono/administração & dosagem , Radioisótopos de Carbono/farmacocinética , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Fezes/química , Humanos , Imidazóis/metabolismo , Inativação Metabólica , Macaca fascicularis , Masculino , Pessoa de Meia-Idade , Ácidos Nicotínicos/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Adulto Jovem
7.
J Am Chem Soc ; 139(9): 3528-3536, 2017 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-28230359

RESUMO

A compact and stable bicyclic bridged ketal was developed as a ligand for the asialoglycoprotein receptor (ASGPR). This compound showed excellent ligand efficiency, and the molecular details of binding were revealed by the first X-ray crystal structures of ligand-bound ASGPR. This analogue was used to make potent di- and trivalent binders of ASGPR. Extensive characterization of the function of these compounds showed rapid ASGPR-dependent cellular uptake in vitro and high levels of liver/plasma selectivity in vivo. Assessment of the biodistribution in rodents of a prototypical Alexa647-labeled trivalent conjugate showed selective hepatocyte targeting with no detectable distribution in nonparenchymal cells. This molecule also exhibited increased ASGPR-directed hepatocellular uptake and prolonged retention compared to a similar GalNAc derived trimer conjugate. Selective release in the liver of a passively permeable small-molecule cargo was achieved by retro-Diels-Alder cleavage of an oxanorbornadiene linkage, presumably upon encountering intracellular thiol. Therefore, the multicomponent construct described here represents a highly efficient delivery vehicle to hepatocytes.


Assuntos
Receptor de Asialoglicoproteína/metabolismo , Compostos Bicíclicos com Pontes/química , Hepatócitos/metabolismo , Cetonas/química , Fígado/metabolismo , Polímeros/química , Compostos Bicíclicos com Pontes/metabolismo , Cristalografia por Raios X , Portadores de Fármacos/química , Humanos , Cetonas/metabolismo , Fígado/citologia , Modelos Moleculares , Estrutura Molecular , Polímeros/metabolismo
8.
Drug Metab Dispos ; 45(5): 576-580, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28258068

RESUMO

The ability to predict human liver-to-plasma unbound partition coefficient (Kpuu) is of great importance to estimate unbound liver concentration, develop PK/PD relationships, predict efficacy and toxicity in the liver, and model the drug-drug interaction potential for drugs that are asymmetrically distributed into the liver. A novel in vitro method has been developed to predict in vivo Kpuu with good accuracy using cryopreserved suspension hepatocytes in InVitroGRO HI media with 4% BSA. Validation was performed using six OATP substrates with rat in vivo Kpuu data from i.v. infusion studies where a steady state was achieved. Good in vitro-in vivo correlation (IVIVE) was observed as the in vitro Kpuu values were mostly within 2-fold of in vivo Kpuu Good Kpuu IVIVE in human was also observed with in vivo Kpuu data of dehydropravastatin from positron emission tomography and in vivo Kpuu data from PK/PD modeling for pravastatin and rosuvastatin. Under the specific Kpuu assay conditions, the drug-metabolizing enzymes and influx/efflux transporters appear to function at physiologic levels. No scaling factors are necessary to predict in vivo Kpuu from in vitro data. The novel in vitro Kpuu method provides a useful tool in drug discovery to project in vivo Kpuu.


Assuntos
Descoberta de Drogas/métodos , Hepatócitos/metabolismo , Fígado/metabolismo , Modelos Biológicos , Transportadores de Ânions Orgânicos/metabolismo , Preparações Farmacêuticas/sangue , Animais , Células Cultivadas , Hepatócitos/efeitos dos fármacos , Humanos , Masculino , Preparações Farmacêuticas/metabolismo , Valor Preditivo dos Testes , Ratos , Ratos Wistar , Especificidade por Substrato
9.
Cutan Ocul Toxicol ; 36(3): 211-219, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27817210

RESUMO

Context Incontinence-associated dermatitis (IAD) is a type of moisture-associated dermatitis caused by repeated skin exposure to urine or stool. A product that could mitigate such symptoms would have a significant impact on cost of care and patients' quality of life. Objective This study compared the clinical efficacy of RD1433 and a comparator product (Vaseline®) in preventing and treating experimental IAD skin lesions. Materials and methods For the "prevention" part of the study, skin sites in eight human volunteers were treated daily for 5 d with either RD1433 or Vaseline® immediately prior to synthetic urine exposure. In the "treatment" part, exposure to synthetic urine was substituted for Vaseline® or RD1433 application on the first 2 d to promote the development of skin lesions prior to the application of the products from day three. Product efficacy was quantified by visual scoring and an array of biophysical instruments. Results Both RD1433 and Vaseline® significantly reduced lesion progression when applied as a prophylactic. When applied as a treatment (following establishment of skin lesions), RD1433 demonstrated a statistically significant improvement in several measures of skin function whereas there was no statistically significant improvement following treatment with Vaseline®. Conclusions The findings of this study suggest that RD1433 may be superior to Vaseline® in the prevention and treatment of experimental IAD lesions. Clearly, further work is required to establish the efficacy of RD1433 with patients in a clinical environment.


Assuntos
Dermatite , Substâncias Protetoras/uso terapêutico , Creme para a Pele/uso terapêutico , Incontinência Urinária/complicações , Administração Tópica , Adulto , Idoso , Idoso de 80 Anos ou mais , Dermatite/tratamento farmacológico , Dermatite/etiologia , Dermatite/prevenção & controle , Éteres/uso terapêutico , Feminino , Fluorocarbonos/uso terapêutico , Humanos , Irritantes , Masculino , Pessoa de Meia-Idade , Vaselina/uso terapêutico , Politetrafluoretileno/uso terapêutico , Pele/efeitos dos fármacos , Resultado do Tratamento , Urina
10.
Angew Chem Int Ed Engl ; 56(51): 16218-16222, 2017 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-29073340

RESUMO

Targeting of the human ribosome is an unprecedented therapeutic modality with a genome-wide selectivity challenge. A liver-targeted drug candidate is described that inhibits ribosomal synthesis of PCSK9, a lipid regulator considered undruggable by small molecules. Key to the concept was the identification of pharmacologically active zwitterions designed to be retained in the liver. Oral delivery of the poorly permeable zwitterions was achieved by prodrugs susceptible to cleavage by carboxylesterase 1. The synthesis of select tetrazole prodrugs was crucial. A cell-free in vitro translation assay containing human cell lysate and purified target mRNA fused to a reporter was used to identify active zwitterions. In vivo PCSK9 lowering by oral dosing of the candidate prodrug and quantification of the drug fraction delivered to the liver utilizing an oral positron emission tomography 18 F-isotopologue validated our liver-targeting approach.


Assuntos
Fígado/efeitos dos fármacos , Inibidores de PCSK9 , Pró-Proteína Convertase 9/biossíntese , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Dose-Resposta a Droga , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Fígado/enzimologia , Fígado/metabolismo , Estrutura Molecular , Pró-Proteína Convertase 9/metabolismo , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade
11.
Drug Metab Dispos ; 44(3): 460-5, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26700955

RESUMO

A novel cytochrome P450 (P450) reaction phenotyping method for low-clearance compounds has been developed for eight P450 enzymes (CYP1A2, 2B6, 2D6, 2C8, 2C9, 2C19, 3A, and 3A4) and pan-cytochrome using the hepatocyte relay approach. Selective mechanism-based inhibitors were used to inactivate the individual P450 enzymes during preincubation, and inactivators were removed from the incubation before adding substrates to minimize reversible inhibition and maximize inhibitor specificity. The inhibitors were quite selective for specific P450 isoforms using the following inhibitor concentrations and preincubation times: furafylline (1 µM, 15 minutes) for CYP1A2, phencyclidine (20 µM, 15 minutes) for 2B6, paroxetine (1.8 µM, 15 minutes) for CYP2D6, gemfibrozil glucuronide (100 µM, 30 minutes) for 2C8, tienilic acid (15 µM, 30 minutes) for 2C9, esomeprazole (8 µM, 15 minutes) for 2C19, troleandomycin (25 µM, 15 minutes) for 3A4/5, CYP3cide (2 µM, 15 minutes) for 3A4, and 1-aminobenzotriazole (1 mM, 30 minutes) supplemented with tienilic acid (15 µM, 30 minutes) for pan-cytochrome. The inhibitors were successfully applied to the hepatocyte relay method in a 48-well format for P450 reaction phenotyping of low-clearance compounds. This novel method provides a new approach for determining the fraction metabolized of low-turnover compounds that are otherwise challenging with the traditional methods, such as chemical inhibitors with human liver microsomes and hepatocytes or human recombinant P450 enzymes.


Assuntos
Inibidores das Enzimas do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Hepatócitos/metabolismo , Interações Medicamentosas/fisiologia , Feminino , Humanos , Cinética , Masculino , Microssomos Hepáticos/metabolismo
12.
Drug Metab Dispos ; 43(2): 190-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25384899

RESUMO

A previous report from our laboratory disclosed the identification of PF-04991532 [(S)-6-(3-cyclopentyl-2-(4-trifluoromethyl)-1H-imidazol-1-yl)propanamido)nicotinic acid] as a hepatoselective glucokinase activator for the treatment of type 2 diabetes mellitus. Lack of in vitro metabolic turnover in microsomes and hepatocytes from preclinical species and humans suggested that metabolism would be inconsequential as a clearance mechanism of PF-04991532 in vivo. Qualitative examination of human circulating metabolites using plasma samples from a 14-day multiple ascending dose clinical study, however, revealed a glucuronide (M1) and monohydroxylation products (M2a and M2b/M2c) whose abundances (based on UV integration) were greater than 10% of the total drug-related material. Based on this preliminary observation, mass balance/excretion studies were triggered in animals, which revealed that the majority of circulating radioactivity following the oral administration of [¹4C]PF-04991532 was attributed to an unchanged parent (>70% in rats and dogs). In contrast with the human circulatory metabolite profile, the monohydroxylated metabolites were not detected in circulation in either rats or dogs. Available mass spectral evidence suggested that M2a and M2b/M2c were diastereomers derived from cyclopentyl ring oxidation in PF-04991532. Because cyclopentyl ring hydroxylation on the C-2 and C-3 positions can generate eight possible diastereomers, it was possible that additional diastereomers may have also formed and would need to be resolved from the M2a and M2b/M2c peaks observed in the current chromatography conditions. In conclusion, the human metabolite scouting study in tandem with the animal mass balance study allowed early identification of PF-04991532 oxidative metabolites, which were not predicted by in vitro methods and may require additional scrutiny in the development phase of PF-04991532.


Assuntos
Ativadores de Enzimas/farmacocinética , Glucoquinase/metabolismo , Hipoglicemiantes/farmacocinética , Imidazóis/farmacocinética , Fígado/efeitos dos fármacos , Ácidos Nicotínicos/farmacocinética , Idoso , Animais , Animais Endogâmicos , Biotransformação , Radioisótopos de Carbono , Cães , Avaliação Pré-Clínica de Medicamentos , Ativadores de Enzimas/análise , Ativadores de Enzimas/sangue , Ativadores de Enzimas/urina , Fezes/química , Feminino , Glucoquinase/química , Meia-Vida , Humanos , Hipoglicemiantes/análise , Hipoglicemiantes/sangue , Hipoglicemiantes/urina , Imidazóis/análise , Imidazóis/sangue , Imidazóis/urina , Fígado/enzimologia , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Estrutura Molecular , Ácidos Nicotínicos/análise , Ácidos Nicotínicos/sangue , Ácidos Nicotínicos/urina , Especificidade de Órgãos , Ratos Sprague-Dawley
13.
Drug Metab Dispos ; 42(11): 1926-39, 2014 11.
Artigo em Inglês | MEDLINE | ID: mdl-25142735

RESUMO

The present article summarizes Metabolites in Safety Testing (MIST) studies on a glucokinase activator, N,N-dimethyl-5-((2-methyl-6-((5-methylpyrazin-2-yl)carbamoyl)benzofuran-4-yl)oxy)pyrimidine-2-carboxamide (PF-04937319), which is under development for the treatment of type 2 diametes mellitus. Metabolic profiling in rat, dog, and human hepatocytes revealed that PF-04937319 is metabolized via oxidative (major) and hydrolytic pathways (minor). N-Demethylation to metabolite M1 [N-methyl-5-((2-methyl-6-((5-methylpyrazin-2-yl)carbamoyl)benzofuran-4-yl)oxy)pyrimidine-2-carboxamide] was the major metabolic fate of PF-04937319 in human (but not rat or dog) hepatocytes, and was catalyzed by CYP3A and CYP2C isoforms. Qualitative examination of circulating metabolites in humans at the 100- and 300-mg doses from a 14-day multiple dose study revealed unchanged parent drug and M1 as principal components. Because M1 accounted for 65% of the drug-related material at steady state, an authentic standard was synthesized and used for comparison of steady-state exposures in humans and the 3-month safety studies in rats and dogs at the no-observed-adverse-effect level. Although circulating levels of M1 were very low in beagle dogs and female rats, adequate coverage was obtained in terms of total maximal plasma concentration (∼7.7× and 1.8×) and area under the plasma concentration-time curve (AUC; 3.6× and 0.8× AUC) relative to the 100- and 300-mg doses, respectively, in male rats. Examination of primary pharmacology revealed M1 was less potent as a glucokinase activator than the parent drug (compound PF-04937319: EC50 = 0.17 µM; M1: EC50 = 4.69 µM). Furthermore, M1 did not inhibit major human P450 enzymes (IC50 > 30 µM), and was negative in the Salmonella Ames assay, with minimal off-target pharmacology, based on CEREP broad ligand profiling. Insights gained from this analysis should lead to a more efficient and focused development plan for fulfilling MIST requirements with PF-04937319.


Assuntos
Benzofuranos/farmacocinética , Ativadores de Enzimas/farmacocinética , Glucoquinase/metabolismo , Pirimidinas/farmacocinética , Animais , Área Sob a Curva , Benzofuranos/sangue , Cães , Ativadores de Enzimas/sangue , Feminino , Humanos , Pirimidinas/sangue , Ratos
14.
Bioorg Med Chem Lett ; 24(3): 839-44, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24418771

RESUMO

Identification of orally active, small molecule antagonists of the glucagon receptor represents a novel treatment paradigm for the management of type 2 diabetes mellitus. The present work discloses novel glucagon receptor antagonists, identified via conformational constraint of current existing literature antagonists. Optimization of lipophilic ligand efficiency (LLE or LipE) culminated in enantiomers (+)-trans-26 and (-)-trans-27 which exhibit good physicochemical and in vitro drug metabolism profiles. In vivo, significant pharmacokinetic differences were noted with the two enantiomers, which were primarily driven through differences in clearance rates. Enantioselective oxidation by cytochrome P450 was ruled out as a causative factor for pharmacokinetic differences.


Assuntos
Benzamidas/química , Pirimidinas/química , Receptores de Glucagon/antagonistas & inibidores , Administração Intravenosa , Administração Oral , Animais , Benzamidas/farmacocinética , Benzamidas/farmacologia , Células Cultivadas , Cães , Ligantes , Conformação Molecular , Estrutura Molecular , Oxirredução , Ligação Proteica/efeitos dos fármacos , Pirimidinas/farmacocinética , Pirimidinas/farmacologia , Ratos , Ratos Wistar , Estereoisomerismo
15.
medRxiv ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38883745

RESUMO

Background: Implicit bias can influence behavior and decision-making. In clinical settings, implicit bias may influence treatment decisions and contribute to health disparities. Given documented Black-White disparities in vascular care, the purpose of this study was to examine the prevalence and degree of unconscious bias and awareness of bias among vascular surgeons treating peripheral artery disease (PAD). Methods: The sampling frame included all vascular surgeons who participate in the Vascular Quality Initiative (VQI). Participants completed a survey which included demographic questions, the race implicit association test (IAT) to measure magnitude of unconscious bias, and six bias awareness questions to measure conscious bias. The magnitude of unconscious bias was no preference; or slight, moderate, or strong in the direction of pro-White or pro-Black. Data from participants were weighted to account for nonresponse bias and known differences in the characteristics of surgeons who chose to participate compared to the full registry. We stratified unconscious and conscious findings by physician race/ethnicity, physician sex, and years of experience. Finally, we examined the relationship between unconscious and conscious bias. Results: There were 2,512 surgeons in the VQI registry, 304 of whom completed the survey, including getting IAT results. Most participants (71.6%) showed a pro-White bias with 73.0% of this group in the moderate and strong categories. While 77.5% of respondents showed conscious awareness of bias, of those whose conscious results showed lack of awareness, 67.8% had moderate or strong bias, compared to 55.7% for those with awareness. Bias magnitude varied based on physician race/ethnicity and years of experience. Women were more likely than men to report awareness of biases and potential impact of bias on decision-making. Conclusions: Most people have some level of unconscious bias, developed from early life reinforcements, social stereotypes, and learned experiences. Regarding health disparities, however, these are important findings in a profession that takes care of patients with PAD due to heavy burden of comorbid conditions and high proportion of individuals from structurally vulnerable groups. Given the lack of association between unconscious and conscious awareness of biases, awareness may be an important first step in mitigation to minimize racial disparities in healthcare.

16.
Drug Metab Dispos ; 41(12): 2018-23, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23857891

RESUMO

In vitro-in vivo correlation (IVIVC) of intrinsic clearance in preclinical species of rat and dog was established using the hepatocyte relay method to support high-confidence prediction of human pharmacokinetics for low-clearance compounds. Good IVIVC of intrinsic clearance was observed for most of the compounds, with predicted values within 2-fold of the observed values. The exceptions involved transporter-mediated uptake clearance or metabolizing enzymes with extensive extrahepatic contribution. This is the first assay available to address low clearance challenges in preclinical species for IVIVC in drug discovery. It extends the utility of the hepatocyte relay method in addressing low clearance issues.


Assuntos
Hepatócitos/metabolismo , Taxa de Depuração Metabólica/efeitos dos fármacos , Animais , Cães , Descoberta de Drogas/métodos , Avaliação Pré-Clínica de Medicamentos , Masculino , Proteínas de Membrana Transportadoras/metabolismo , Ratos , Ratos Wistar
17.
Bioorg Med Chem Lett ; 23(24): 6588-92, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24239482

RESUMO

Glucokinase (hexokinase IV) continues to be a compelling target for the treatment of type 2 diabetes given the wealth of supporting human genetics data and numerous reports of robust clinical glucose lowering in patients treated with small molecule allosteric activators. Recent work has demonstrated the ability of hepatoselective activators to deliver glucose lowering efficacy with minimal risk of hypoglycemia. While orally administered agents require a considerable degree of passive permeability to promote suitable exposures, there is no such restriction on intravenously delivered drugs. Therefore, minimization of membrane diffusion in the context of an intravenously agent should ensure optimal hepatic targeting and therapeutic index. This work details the identification a hepatoselective GKA exhibiting the aforementioned properties.


Assuntos
Ativadores de Enzimas/química , Glucoquinase/química , Hipoglicemiantes/química , Regulação Alostérica , Animais , Células Cultivadas , Diabetes Mellitus Tipo 2/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos , Ativadores de Enzimas/metabolismo , Ativadores de Enzimas/uso terapêutico , Glucoquinase/metabolismo , Hepatócitos/citologia , Hepatócitos/enzimologia , Humanos , Hipoglicemiantes/metabolismo , Hipoglicemiantes/uso terapêutico , Imidazóis/química , Injeções Intravenosas , Niacina/análogos & derivados , Niacina/química , Ratos , Distribuição Tecidual
18.
Bioorg Med Chem Lett ; 23(10): 3051-8, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23562063

RESUMO

A novel and potent small molecule glucagon receptor antagonist for the treatment of diabetes mellitus is reported. This candidate, (S)-3-[4-(1-{3,5-dimethyl-4-[4-(trifluoromethyl)-1H-pyrazol-1-yl]phenoxy}butyl)benzamido]propanoic acid, has lower molecular weight and lipophilicity than historical glucagon receptor antagonists, resulting in excellent selectivity in broad-panel screening, lower cytotoxicity, and excellent overall in vivo safety in early pre-clinical testing. Additionally, it displays low in vivo clearance and excellent oral bioavailability in both rats and dogs. In a rat glucagon challenge model, it was shown to reduce the glucagon-elicited glucose excursion in a dose-dependent manner and at a concentration consistent with its rat in vitro potency. Its properties make it an excellent candidate for further investigation.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Desenho de Fármacos , Propionatos/farmacologia , Receptores de Glucagon/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Físico-Química , Cães , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Haplorrinos , Humanos , Fígado/citologia , Camundongos , Estrutura Molecular , Propionatos/administração & dosagem , Propionatos/síntese química , Ratos , Bibliotecas de Moléculas Pequenas/administração & dosagem , Bibliotecas de Moléculas Pequenas/síntese química , Relação Estrutura-Atividade
19.
Bioorg Med Chem Lett ; 23(16): 4571-8, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23831135

RESUMO

Glucokinase activators are a class of experimental agents under investigation as a therapy for Type 2 diabetes mellitus. An X-ray crystal structure of a modestly potent agent revealed the potential to substitute the common heterocyclic amide donor-acceptor motif for a pyridone moiety. We have successfully demonstrated that both pyridone and pyrimidone heterocycles can be used as a potent donor-acceptor substituent. Several sub-micromolar analogs that possess the desired partial activator profile were synthesized and characterized. Unfortunately, the most potent activators suffered from sub-optimal pharmacokinetic properties. Nonetheless, these donor-acceptor motifs may find utility in other glucokinase activator series or beyond.


Assuntos
Ativadores de Enzimas/química , Glucoquinase/metabolismo , Pirimidinonas/síntese química , Regulação Alostérica , Motivos de Aminoácidos , Animais , Sítios de Ligação , Modelos Moleculares , Pirimidinonas/química , Ratos
20.
Healthcare (Basel) ; 11(22)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37998417

RESUMO

BACKGROUND: Kidney disease is a progressive, debilitating condition. Patients experience challenging physical and psychological symptoms and are at increased risk of anxiety, depression, and poor mental wellbeing. Access to specialist psychological or social support is limited, with inadequate provision of psychosocial support available across UK renal units. The COSMIC study (examining the acceptability and feasibility of the Compassionate Mindful Resilience programme for adult patients with chronic kidney disease) aimed to support a new service development project, in partnership with Kidney Care UK, by implementing the Compassionate Mindful Resilience (CMR) programme, developed by MindfulnessUK, and explore its feasibility for patients with stage 4 or 5 kidney disease and kidney transplant recipients. This paper reports on the qualitative exploratory work which examined the experiences of study participants, their adherence to practice, and the acceptability of the intervention. METHOD: Participants (n = 19) took part in semi-structured interviews, which were transcribed, coded, and thematically analysed. RESULTS: Three themes (and nine subthemes) were reported: experiences of the CMR programme that facilitated subjective benefit, participants' lived and shared experiences, and the practicalities of CMR programme participation. All participants reported that they found taking part in the CMR programme to be a beneficial experience. CONCLUSION: The CMR programme was found to be an acceptable intervention for people living with kidney disease and provided tools and techniques that support the mental health and wellbeing of this patient group. Further qualitative exploration into participant experience should be integrated within future trials of this intervention.

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