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1.
Cell ; 168(5): 878-889.e29, 2017 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-28235199

RESUMO

Design of small molecules that disrupt protein-protein interactions, including the interaction of RAS proteins and their effectors, may provide chemical probes and therapeutic agents. We describe here the synthesis and testing of potential small-molecule pan-RAS ligands, which were designed to interact with adjacent sites on the surface of oncogenic KRAS. One compound, termed 3144, was found to bind to RAS proteins using microscale thermophoresis, nuclear magnetic resonance spectroscopy, and isothermal titration calorimetry and to exhibit lethality in cells partially dependent on expression of RAS proteins. This compound was metabolically stable in liver microsomes and displayed anti-tumor activity in xenograft mouse cancer models. These findings suggest that pan-RAS inhibition may be an effective therapeutic strategy for some cancers and that structure-based design of small molecules targeting multiple adjacent sites to create multivalent inhibitors may be effective for some proteins.


Assuntos
Antineoplásicos/farmacologia , Terapia de Alvo Molecular , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/química , Animais , Antineoplásicos/química , Calorimetria , Linhagem Celular , Fibroblastos/metabolismo , Xenoenxertos , Humanos , Camundongos , Transplante de Neoplasias , Neoplasias/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras , Transdução de Sinais , Bibliotecas de Moléculas Pequenas
2.
J Chem Inf Model ; 63(6): 1656-1667, 2023 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-36897766

RESUMO

The recently developed AlphaFold2 (AF2) algorithm predicts proteins' 3D structures from amino acid sequences. The open AlphaFold protein structure database covers the complete human proteome. Using an industry-leading molecular docking method (Glide), we investigated the virtual screening performance of 37 common drug targets, each with an AF2 structure and known holo and apo structures from the DUD-E data set. In a subset of 27 targets where the AF2 structures are suitable for refinement, the AF2 structures show comparable early enrichment of known active compounds (avg. EF 1%: 13.0) to apo structures (avg. EF 1%: 11.4) while falling behind early enrichment of the holo structures (avg. EF 1%: 24.2). With an induced-fit protocol (IFD-MD), we can refine the AF2 structures using an aligned known binding ligand as the template to improve the performance in structure-based virtual screening (avg. EF 1%: 18.9). Glide-generated docking poses of known binding ligands can also be used as templates for IFD-MD, achieving similar improvements (avg. EF 1% 18.0). Thus, with proper preparation and refinement, AF2 structures show considerable promise for in silico hit identification.


Assuntos
Benchmarking , Furilfuramida , Humanos , Sítios de Ligação , Simulação de Acoplamento Molecular , Ligação Proteica , Fator 1 de Elongação de Peptídeos/metabolismo , Proteínas/química , Ligantes
3.
BMC Pregnancy Childbirth ; 21(1): 51, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33435904

RESUMO

BACKGROUND: Severe early onset (less than 34 weeks gestation) intrahepatic cholestasis of pregnancy (ICP) affects 0.1% of pregnant women in Australia and is associated with a 3-fold increased risk of stillbirth, fetal hypoxia and compromise, spontaneous preterm birth, as well as increased frequencies of pre-eclampsia and gestational diabetes. ICP is often familial and overlaps with other cholestatic disorders. Treatment options for ICP are not well established, although there are limited data to support the use of ursodeoxycholic acid (UDCA) to relieve pruritus, the main symptom. Rifampicin, a widely used antibiotic including in pregnant women, is effective in reducing pruritus in non-pregnancy cholestasis and has been used as a supplement to UDCA in severe ICP. Many women with ICP are electively delivered preterm, although there are no randomised data to support this approach. METHODS: We have initiated an international multicentre randomised clinical trial to compare the clinical efficacy of rifampicin tablets (300 mg bd) with that of UDCA tablets (up to 2000 mg daily) in reducing pruritus in women with ICP, using visual pruritus scores as a measuring tool. DISCUSSION: Our study will be the first to examine the outcomes of treatment specifically in the severe early onset form of ICP, comparing "standard" UDCA therapy with rifampicin, and so be able to provide for the first-time high-quality evidence for use of rifampicin in severe ICP. It will also allow an assessment of feasibility of a future trial to test whether elective early delivery in severe ICP is beneficial. TRIAL IDENTIFIERS: Australian New Zealand Clinical Trials Registration Number (ANZCTR): 12618000332224p (29/08/2018). HREC No: HREC/18/WCHN/36. EudraCT number: 2018-004011-44. IRAS: 272398. NHMRC registration: APP1152418 and APP117853.


Assuntos
Antipruriginosos/uso terapêutico , Colestase Intra-Hepática/tratamento farmacológico , Complicações na Gravidez/tratamento farmacológico , Rifampina/uso terapêutico , Ácido Ursodesoxicólico/uso terapêutico , Antipruriginosos/administração & dosagem , Austrália , Feminino , Humanos , Gravidez , Resultado da Gravidez , Rifampina/administração & dosagem , Resultado do Tratamento , Ácido Ursodesoxicólico/administração & dosagem
4.
Biochemistry ; 59(4): 479-490, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-31869219

RESUMO

Point mutations in human isocitrate dehydrogenase 1 (IDH1) can drive malignancies, including lower-grade gliomas and secondary glioblastomas, chondrosarcomas, and acute myeloid leukemias. These mutations, which usually affect residue R132, ablate the normal activity of catalyzing the NADP+-dependent oxidation of isocitrate to α-ketoglutarate (αKG) while also acquiring a neomorphic activity of reducing αKG to d-2-hydroxyglutarate (D2HG). Mutant IDH1 can be selectively therapeutically targeted due to structural differences that occur in the wild type (WT) versus mutant form of the enzyme, though the full mechanisms of this selectivity are still under investigation. Here we probe the mechanistic features of the neomorphic activity and selective small molecule inhibition through a new lens, employing WaterMap and molecular dynamics simulations. These tools identified a high-energy path of water molecules connecting the inhibitor binding site with the αKG and NADP+ binding sites in mutant IDH1. This water path aligns spatially with the α10 helix from WT IDH1 crystal structures. Mutating residues at the termini of this water path specifically disrupted inhibitor binding and/or D2HG production, revealing additional key residues to consider in optimizing druglike molecules against mutant IDH1. Taken together, our findings from molecular simulations and mutant enzyme kinetic assays provide insight into how disrupting water paths through enzyme active sites can impact not only inhibitor potency but also substrate recognition and activity.


Assuntos
Isocitrato Desidrogenase/química , Isocitrato Desidrogenase/genética , Sítios de Ligação/genética , Fenômenos Biofísicos , Catálise , Domínio Catalítico/genética , Glutaratos/metabolismo , Humanos , Isocitrato Desidrogenase/antagonistas & inibidores , Isocitratos , Ácidos Cetoglutáricos/metabolismo , Cinética , Simulação de Dinâmica Molecular , Mutação/genética , Água/química
5.
Biochemistry ; 58(21): 2542-2554, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31042025

RESUMO

KRAS is the most commonly mutated oncogene in human cancer, with particularly high mutation frequencies in pancreatic cancers, colorectal cancers, and lung cancers [Ostrem, J. M., and Shokat, K. M. (2016) Nat. Rev. Drug Discovery 15, 771-785]. The high prevalence of KRAS mutations and its essential role in many cancers make it a potentially attractive drug target; however, it has been difficult to create small molecule inhibitors of mutant K-Ras proteins. Here, we identified a putative small molecule binding site on K-RasG12D using computational analyses of the protein structure and then used a combination of computational and biochemical approaches to discover small molecules that may bind to this pocket, which we have termed the P110 site, due to its adjacency to proline 110. We confirmed that one compound, named K-Ras allosteric ligand KAL-21404358, bound to K-RasG12D, as measured by microscale thermophoresis, a thermal shift assay, and nuclear magnetic resonance spectroscopy. KAL-21404358 did not bind to four mutants in the P110 site, supporting our hypothesis that KAL-21404358 binds to the P110 site of K-RasG12D. This compound impaired the interaction of K-RasG12D with B-Raf and disrupted the RAF-MEK-ERK and PI3K-AKT signaling pathways. We synthesized additional compounds, based on the KAL-21404358 scaffold with more potent binding and greater aqueous solubility. In summary, these findings suggest that the P110 site is a potential site for binding of small molecule allosteric inhibitors of K-RasG12D.


Assuntos
Sítio Alostérico/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/química , Domínio Catalítico , Linhagem Celular Tumoral , Descoberta de Drogas/métodos , Escherichia coli/metabolismo , Células HEK293 , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Proteínas Mutantes/antagonistas & inibidores , Proteínas Mutantes/química , Fosfatidilinositol 3-Quinases/metabolismo , Ligação Proteica , Estrutura Secundária de Proteína , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Transfecção
6.
Prehosp Emerg Care ; 22(4): 506-510, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29447489

RESUMO

BACKGROUND: Backboards have been shown to cause pain in uninjured patients. This may alter physical exam findings, leading emergency department (ED) providers to suspect a spinal injury when none exists resulting in additional imaging of the thoracolumbar spine. New York had previously employed a "Spinal Immobilization" protocol that included compulsory backboard application for all patients with suspected spinal injuries. In 2015, New York instituted a new "Spinal Motion Restriction" protocol that made backboard use optional for these patients. The objective of this study was to determine if this protocol change was associated with decreased backboard utilization and ED thoracolumbar spine imaging. METHODS: This was a retrospective before-and-after chart review of subjects transported by a single emergency medical services (EMS) agency to one of four EDs for emergency calls dispatched as motor vehicle collisions (MVC). EMS and ED data were included for all calls within a 6-month interval before and after the protocol change. The protocol change was implemented in the second half of 2015. Subject demographics, backboard use, and spine imaging were reviewed for the intervals January-June 2015 and January-June 2016. RESULTS: There were 818 subjects in the before period and 796 subjects in the after period. Subjects were similar in terms of gender, age and type of MVC in both periods. A backboard was utilized for 440 (54%) subjects in the before period and 92 (12%) subjects in the after period (p < 0.001). ED thoracic spine imaging was performed on 285 (35%) subjects in the before period, and 235 (30%) subjects in the after period (p = 0.02). ED lumbar spine imaging was performed for 335 (41%) subjects in the before period, and 281 (35%) subjects in the after period (p = 0.02). CONCLUSION: A shift from a spinal immobilization protocol to a spinal motion restriction protocol was associated with a decrease in backboard utilization by EMS providers and a decrease in thoracolumbar spine imaging by ED providers.


Assuntos
Protocolos Clínicos , Diagnóstico por Imagem/métodos , Serviços Médicos de Emergência , Imobilização/instrumentação , Traumatismos da Coluna Vertebral/diagnóstico por imagem , Acidentes de Trânsito , Adolescente , Adulto , Feminino , Humanos , Masculino , Auditoria Médica , Pessoa de Meia-Idade , New York , Estudos Retrospectivos
7.
J Interprof Care ; 31(1): 122-124, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27918860

RESUMO

There is a growing interest in interprofessional care (IPC) as a way to provide better healthcare. However, it is difficult to evaluate this mode of healthcare delivery because identifying the appropriate measurement tool is a challenge, given the wide diversity in team composition and settings. Adding to this complexity is a key gap in the IPC evaluation research: the client/patient perspective. This perspective has generally not been included in the development of IPC healthcare team evaluations. The authors received a Canadian Institute for Health Research Planning Grant to host a one-day forum with 24 participants from across Canada representing health professions such as social work, medicine, occupational therapy, and physical therapy, in addition to researchers, client/patient advocates, and hospital administrators. The overarching goal of the forum was to create a demonstration project that supports the development of an IPC assessment tool for healthcare teams that includes clients/patients. Using a concept mapping methodology, participants discussed client/patient inclusion in IPC assessments, and through a consensus process, chose a demonstration project for further development.


Assuntos
Relações Interprofissionais , Equipe de Assistência ao Paciente/normas , Indicadores de Qualidade em Assistência à Saúde , Comportamento Cooperativo , Processos Grupais , Pessoal de Saúde/psicologia , Administradores Hospitalares/psicologia , Humanos , Pacientes/psicologia , Projetos de Pesquisa , Pesquisadores/psicologia , Assistentes Sociais/psicologia
8.
PLoS Pathog ; 10(1): e1003888, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24465208

RESUMO

Leishmania parasites alternate between extracellular promastigote stages in the insect vector and an obligate intracellular amastigote stage that proliferates within the phagolysosomal compartment of macrophages in the mammalian host. Most enzymes involved in Leishmania central carbon metabolism are constitutively expressed and stage-specific changes in energy metabolism remain poorly defined. Using (13)C-stable isotope resolved metabolomics and (2)H2O labelling, we show that amastigote differentiation is associated with reduction in growth rate and induction of a distinct stringent metabolic state. This state is characterized by a global decrease in the uptake and utilization of glucose and amino acids, a reduced secretion of organic acids and increased fatty acid ß-oxidation. Isotopomer analysis showed that catabolism of hexose and fatty acids provide C4 dicarboxylic acids (succinate/malate) and acetyl-CoA for the synthesis of glutamate via a compartmentalized mitochondrial tricarboxylic acid (TCA) cycle. In vitro cultivated and intracellular amastigotes are acutely sensitive to inhibitors of mitochondrial aconitase and glutamine synthetase, indicating that these anabolic pathways are essential for intracellular growth and virulence. Lesion-derived amastigotes exhibit a similar metabolism to in vitro differentiated amastigotes, indicating that this stringent response is coupled to differentiation signals rather than exogenous nutrient levels. Induction of a stringent metabolic response may facilitate amastigote survival in a nutrient-poor intracellular niche and underlie the increased dependence of this stage on hexose and mitochondrial metabolism.


Assuntos
Aminoácidos/metabolismo , Ciclo do Ácido Cítrico/fisiologia , Glucose/metabolismo , Leishmania mexicana/metabolismo , Leishmaniose Cutânea/metabolismo , Mitocôndrias/metabolismo , Aminoácidos/genética , Animais , Feminino , Glucose/genética , Leishmania mexicana/genética , Leishmaniose Cutânea/genética , Macrófagos/metabolismo , Macrófagos/parasitologia , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/genética
9.
Bioorg Med Chem Lett ; 26(2): 262-264, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26718843

RESUMO

The total synthesis of a biotinylated derivative of methyl rocaglate is described. This compound was accessed from synthetic methyl rocaglate (2) via formation of the propargyl amide and subsequent click reaction with a biotin azide. Affinity purification revealed that biotinylated rocaglate (8) and methyl rocaglate (2) bind with high specificity to translation factors eIF4AI/II. This remarkable selectivity is in line with that found for the more complex rocaglate silvestrol (3).


Assuntos
Benzofuranos/química , Biotina/química , Fator de Iniciação 4A em Eucariotos/química , Animais , Benzofuranos/síntese química , Benzofuranos/farmacologia , Biotina/síntese química , Biotina/farmacologia , Fator de Iniciação 4A em Eucariotos/metabolismo , Camundongos , Coelhos , Triterpenos/química
10.
BMC Fam Pract ; 16: 135, 2015 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26463083

RESUMO

BACKGROUND: Mental health and/or substance use issues are associated with significant disparities in morbidity and mortality. The aim of this study was to identify the mechanisms underlying poor primary care access for this population. METHOD: This was a community-based participatory action qualitative study, in which 85 adults who self-identified as having a serious mental health and/or substance use issue and 17 service providers from various disciplines who worked with this population participated in a semi-structured interview. RESULTS: Client, service provider and health system barriers to access were identified. Client factors, including socioeconomic and psychological barriers, make it difficult for clients to access primary care, keep appointments, and/or prioritize their own health care. Provider factors, including knowledge and personal values related to mental health and substance use, determine the extent to which clients report their specific needs are met in the primary care setting. Health system factors, such as models of primary care delivery, determine the context within which both client and service provider factors operate. CONCLUSIONS: This study helps elucidate the mechanisms behind poor primary health care access among people with substance use and/or mental health issues. The results suggest that interdisciplinary, collaborative models of primary healthcare may improve accessibility and quality of care for this population, and that more education about mental health and substance use issues may be needed to support service providers in providing adequate care for their clients.


Assuntos
Acessibilidade aos Serviços de Saúde , Transtornos Mentais/terapia , Atenção Primária à Saúde , Transtornos Relacionados ao Uso de Substâncias/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Atitude do Pessoal de Saúde , Canadá , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde/organização & administração , Pesquisa Qualitativa , Adulto Jovem
11.
Am J Gastroenterol ; 109(1): 76-84, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24366234

RESUMO

OBJECTIVES: Intrahepatic cholestasis of pregnancy (ICP) has a complex etiology with a significant genetic component. Heterozygous mutations of canalicular transporters occur in a subset of ICP cases and a population susceptibility allele (p.444A) has been identified in ABCB11. We sought to expand our knowledge of the detailed genetic contribution to ICP by investigation of common variation around candidate loci with biological plausibility for a role in ICP (ABCB4, ABCB11, ABCC2, ATP8B1, NR1H4, and FGF19). METHODS: ICP patients (n=563) of white western European origin and controls (n=642) were analyzed in a case-control design. Single-nucleotide polymorphism (SNP) markers (n=83) were selected from the HapMap data set (Tagger, Haploview 4.1 (build 22)). Genotyping was performed by allelic discrimination assay on a robotic platform. Following quality control, SNP data were analyzed by Armitage's trend test. RESULTS: Cochran-Armitage trend testing identified six SNPs in ABCB11 together with six SNPs in ABCB4 that showed significant evidence of association. The minimum Bonferroni corrected P value for trend testing ABCB11 was 5.81×10(-4) (rs3815676) and for ABCB4 it was 4.6×10(-7)(rs2109505). Conditional analysis of the two clusters of association signals suggested a single signal in ABCB4 but evidence for two independent signals in ABCB11. To confirm these findings, a second study was performed in a further 227 cases, which confirmed and strengthened the original findings. CONCLUSIONS: Our analysis of a large cohort of ICP cases has identified a key role for common variation around the ABCB4 and ABCB11 loci, identified the core associations, and expanded our knowledge of ICP susceptibility.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/genética , Colestase Intra-Hepática/genética , Complicações na Gravidez/genética , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Estudos de Casos e Controles , Colestase Intra-Hepática/etnologia , Europa (Continente) , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Heterozigoto , Humanos , Proteína 2 Associada à Farmacorresistência Múltipla , Mutação , Polimorfismo de Nucleotídeo Único , Gravidez , Complicações na Gravidez/etnologia , População Branca/genética
12.
BMC Biol ; 11: 67, 2013 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-23763941

RESUMO

BACKGROUND: The carbon metabolism of the blood stages of Plasmodium falciparum, comprising rapidly dividing asexual stages and non-dividing gametocytes, is thought to be highly streamlined, with glycolysis providing most of the cellular ATP. However, these parasitic stages express all the enzymes needed for a canonical mitochondrial tricarboxylic acid (TCA) cycle, and it was recently proposed that they may catabolize glutamine via an atypical branched TCA cycle. Whether these stages catabolize glucose in the TCA cycle and what is the functional significance of mitochondrial metabolism remains unresolved. RESULTS: We reassessed the central carbon metabolism of P. falciparum asexual and sexual blood stages, by metabolically labeling each stage with 13C-glucose and 13C-glutamine, and analyzing isotopic enrichment in key pathways using mass spectrometry. In contrast to previous findings, we found that carbon skeletons derived from both glucose and glutamine are catabolized in a canonical oxidative TCA cycle in both the asexual and sexual blood stages. Flux of glucose carbon skeletons into the TCA cycle is low in the asexual blood stages, with glutamine providing most of the carbon skeletons, but increases dramatically in the gametocyte stages. Increased glucose catabolism in the gametocyte TCA cycle was associated with increased glucose uptake, suggesting that the energy requirements of this stage are high. Significantly, whereas chemical inhibition of the TCA cycle had little effect on the growth or viability of asexual stages, inhibition of the gametocyte TCA cycle led to arrested development and death. CONCLUSIONS: Our metabolomics approach has allowed us to revise current models of P. falciparum carbon metabolism. In particular, we found that both asexual and sexual blood stages utilize a conventional TCA cycle to catabolize glucose and glutamine. Gametocyte differentiation is associated with a programmed remodeling of central carbon metabolism that may be required for parasite survival either before or after uptake by the mosquito vector. The increased sensitivity of gametocyte stages to TCA-cycle inhibitors provides a potential target for transmission-blocking drugs.


Assuntos
Estágios do Ciclo de Vida , Malária Falciparum/parasitologia , Mitocôndrias/metabolismo , Parasitos/crescimento & desenvolvimento , Parasitos/metabolismo , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/metabolismo , Animais , Ciclo do Ácido Cítrico/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Eritrócitos/parasitologia , Fluoracetatos/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Glucose/metabolismo , Glutamina/metabolismo , Humanos , Estágios do Ciclo de Vida/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Mitocôndrias/efeitos dos fármacos , Modelos Biológicos , Parasitos/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Reprodução Assexuada/efeitos dos fármacos
13.
Anesth Analg ; 117(2): 471-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23757476

RESUMO

BACKGROUND: Postoperative delirium in the elderly, measured days after surgery, is associated with significant negative clinical outcomes. In this study, we evaluated the prevalence and in-hospital outcomes of delirium diagnosed immediately after general anesthesia and surgery in elderly patients. METHODS: Consecutive English-speaking surgical candidates, aged 70 years or older, were prospectively enrolled during July to August 2010. After surgery, each participant was evaluated for a Diagnostic and Statistical Manual of Mental Disorders IV diagnosis of delirium in the postanesthesia care unit (PACU) and repeatedly thereafter while hospitalized. Delirium in the PACU was evaluated for an independent association with change in cognitive function from preoperative baseline testing and discharge disposition. RESULTS: Ninety-one (58% female) patients, 78% of whom were living independently before surgery, were found to have a prevalence of delirium in the PACU of 45% (41/91); 74% (14/19) of all delirium episodes detected during subsequent hospitalization started in the PACU. Early delirium was independently associated with impaired cognition (i.e., decreased category word fluency) relative to presurgery baseline testing (adjusted difference [95% confidence interval] for change in T-score: -6.02 [-10.58 to -1.45]; P = 0.01). Patients whose delirium had resolved by postoperative day 1 showed negative outcomes that were intermediate in severity between those who were never delirious during hospitalization and those whose delirium in the PACU persisted after transfer to hospital wards (adjusted probability [95% confidence interval] of discharge to institution: 3% [0%-10%], 26% [1%-51%], 39% [0%-81%] for the 3 groups, respectively). CONCLUSIONS: Delirium in the PACU is common, but not universal. It is associated with subsequent delirium on the ward, and potentially with a decline in cognitive function and increased institutionalization at hospital discharge.


Assuntos
Anestesia Geral/efeitos adversos , Delírio/diagnóstico , Diagnóstico Precoce , Atividades Cotidianas , Assistência ao Convalescente , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Período de Recuperação da Anestesia , Baltimore/epidemiologia , Cognição , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/psicologia , Delírio/epidemiologia , Delírio/psicologia , Delírio/terapia , Feminino , Humanos , Institucionalização , Modelos Lineares , Modelos Logísticos , Masculino , Análise Multivariada , Testes Neuropsicológicos , Alta do Paciente , Transferência de Pacientes , Valor Preditivo dos Testes , Prevalência , Prognóstico , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Sala de Recuperação , Fatores de Risco , Fatores de Tempo
14.
BMC Sports Sci Med Rehabil ; 15(1): 72, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37365624

RESUMO

BACKGROUND: The hamstrings are an important muscle group that contribute to horizontal force during sprint acceleration and are also the most injured muscle group in running-based sports. Given the significant time loss associated with hamstrings injury and impaired sprinting performance following return to sport, identifying exercises that drive adaptations that are both protective of strain injury and beneficial to sprint performance is important for the strength and conditioning professional. This paper describes the study protocol investigating the effects of a 6-week training program using either the hip-dominant Romanian deadlift (RDL) or the knee-dominant Nordic hamstring exercise (NHE) on hamstring strain injury risk factors and sprint performance. METHODS: A permuted block randomized (1:1 allocation) intervention trial will be conducted involving young, physically-active men and women. A target sample size of 32 will be recruited and enrolled participants will undergo baseline testing involving extended-field-of-view ultrasound imaging and shear wave elastography of the biceps femoris long head muscle, maximal hamstrings strength testing in both the RDL and NHE, and on-field sprint performance and biomechanics. Participants will complete the 6-week training intervention using either the RDL or NHE, according to group allocation. Baseline testing will be repeated at the end of the 6-week intervention followed by 2 weeks of detraining and a final testing session. The primary outcome will be regional changes in fascicle length with secondary outcomes including pennation angle, muscle cross sectional area, hamstring strength, and maximal sprint performance and biomechanics. An exploratory aim will determine changes in shear wave velocity. DISCUSSION: Despite extensive research showing the benefits of the NHE on reducing hamstring strain injury risk, alternative exercises, such as the RDL, may offer similar or potentially even greater benefits. The findings of this study will aim to inform future researchers and practitioners investigating alternatives to the NHE, such as the RDL, in terms of their effectiveness in reducing rates of hamstring strain injury in larger scale prospective intervention studies. TRIAL REGISTRATION: The trial is prospectively registered on ClinicalTrials.gov (NCT05455346; July 15, 2022).

15.
J Biol Chem ; 286(31): 27706-17, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21636575

RESUMO

Leishmania parasites proliferate within nutritionally complex niches in their sandfly vector and mammalian hosts. However, the extent to which these parasites utilize different carbon sources remains poorly defined. In this study, we have followed the incorporation of various (13)C-labeled carbon sources into the intracellular and secreted metabolites of Leishmania mexicana promastigotes using gas chromatography-mass spectrometry and (13)C NMR. [U-(13)C]Glucose was rapidly incorporated into intermediates in glycolysis, the pentose phosphate pathway, and the cytoplasmic carbohydrate reserve material, mannogen. Enzymes involved in the upper glycolytic pathway are sequestered within glycosomes, and the ATP and NAD(+) consumed by these reactions were primarily regenerated by the fermentation of phosphoenolpyruvate to succinate (glycosomal succinate fermentation). The initiating enzyme in this pathway, phosphoenolpyruvate carboxykinase, was exclusively localized to the glycosome. Although some of the glycosomal succinate was secreted, most of the C4 dicarboxylic acids generated during succinate fermentation were further catabolized in the TCA cycle. A high rate of TCA cycle anaplerosis was further suggested by measurement of [U-(13)C]aspartate and [U-(13)C]alanine uptake and catabolism. TCA cycle anaplerosis is apparently needed to sustain glutamate production under standard culture conditions. Specifically, inhibition of mitochondrial aconitase with sodium fluoroacetate resulted in the rapid depletion of intracellular glutamate pools and growth arrest. Addition of high concentrations of exogenous glutamate alleviated this growth arrest. These findings suggest that glycosomal and mitochondrial metabolism in Leishmania promastigotes is tightly coupled and that, in contrast to the situation in some other trypanosomatid parasites, the TCA cycle has crucial anabolic functions.


Assuntos
Ácido Aspártico/metabolismo , Ciclo do Ácido Cítrico , Ácido Glutâmico/biossíntese , Leishmania mexicana/metabolismo , Ácido Succínico/metabolismo , Animais , Sequência de Bases , Carbono/metabolismo , Primers do DNA , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Glucose/metabolismo , Leishmania mexicana/genética , Leishmania mexicana/crescimento & desenvolvimento , Espectroscopia de Ressonância Magnética
16.
J Nat Prod ; 75(8): 1500-4, 2012 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-22817615

RESUMO

The first total synthesis of the low-abundance natural product 2''',5'''-diepisilvestrol (4) is described. The key step involved a Mitsunobu coupling between cyclopenta[b]benzofuran phenol 7 and dioxane lactol 6. Deprotection then gave a 1:2.6 ratio of natural product 2''',5'''-diepisilvestrol (4) and its C1 epimer 1''',2''',5'''-triepisilvestrol (15) in 50% overall yield. An in vitro protein translation inhibition assay showed that 2''',5'''-diepisilvestrol (4) was considerably less active than episilvestrol (2), while the unnatural isomer 1''',2''',5'''-triepisilvestrol (15) was essentially inactive, showing that the configuration at C1''' and C2''' has a large effect on the biological activity.


Assuntos
Benzofuranos/síntese química , Triterpenos/síntese química , Benzofuranos/química , Benzofuranos/farmacologia , Cristalografia por Raios X , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Estereoisomerismo , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/farmacologia
17.
ANZ J Surg ; 92(9): 2305-2311, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35674397

RESUMO

BACKGROUND: Frailty predicts adverse perioperative outcomes and increased mortality in patients having vascular surgery. Frailty assessment is a potential tool to inform resource allocation, and shared decision-making about vascular surgery in the resource constrained COVID-19 pandemic environment. This cohort study describes the prevalence of frailty in patients having vascular surgery and the association between frailty, mortality and perioperative outcomes. METHODS: The COVID-19 Vascular Service in Australia (COVER-AU) prospective cohort study evaluates 30-day and six-month outcomes for consecutive patients having vascular surgery in 11 Australian vascular units, March-July 2020. The primary outcome was mortality, with secondary outcomes procedure-related outcomes and hospital utilization. Frailty was assessed using the nine-point visual Clinical Frailty Score, scores of 5 or more considered frail. RESULTS: Of the 917 patients enrolled, 203 were frail (22.1%). The 30 day and 6 month mortality was 2.0% (n = 20) and 5.9% (n = 35) respectively with no significant difference between frail and non-frail patients (OR 1.68, 95%CI 0.79-3.54). However, frail patients stayed longer in hospital, had more perioperative complications, and were more likely to be readmitted or have a reoperation when compared to non-frail patients. At 6 months, frail patients had twice the odds of major amputation compared to non-frail patients, after adjustment (OR 2.01; 95% CI 1.17-3.78), driven by a high rate of amputation during the period of reduced surgical activity. CONCLUSION: Our findings highlight that older, frail patients, experience potentially preventable adverse outcomes and there is a need for targeted interventions to optimize care, especially in times of healthcare stress.


Assuntos
COVID-19 , Fragilidade , Idoso , Amputação Cirúrgica , Austrália/epidemiologia , COVID-19/epidemiologia , Estudos de Coortes , Idoso Fragilizado , Fragilidade/epidemiologia , Avaliação Geriátrica , Humanos , Tempo de Internação , Pandemias , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Fatores de Risco , Procedimentos Cirúrgicos Vasculares/efeitos adversos
18.
J Psychiatr Ment Health Nurs ; 28(1): 83-89, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33320390

RESUMO

WHAT IS KNOWN?: Police and mental health services benefit from meaningful service user engagement. Partnerships with organizations that are representative of community members-such as service users-are the most empowering model of collaboration. WHAT THIS PAPER ADDS?: Describes how a service user organization can effectively advocate for change in the policing and mental health systems through both mutual collaboration and external pressure. IMPLICATIONS FOR PRACTICE?: Methods of creating change that can save lives through partnerships with service user organizations can be applied by service user organizations, police and mental health services. The methods described have the potential to reduce deaths and injury as a result of police action or mental healthcare practices.


Assuntos
Serviços de Saúde Mental , Polícia , Humanos , Organizações
19.
J Hered ; 101(4): 413-22, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20219886

RESUMO

Dispersal and gene flow are important processes affecting the evolutionary potential of wild populations. Assessing the importance of such patterns is thus critical, especially in contexts where environmental attributes may enhance or restrict the movements of individuals across patchy habitats. A landscape genetics approach is effective in that respect as it combines spatial and genetic data to identify landscape features that play a role in shaping genetic structure. The primary objective of our research was to characterize the determinants of population genetic structure in the eastern chipmunk (Tamias striatus) over a large heterogeneous study area in southern Quebec and Ontario, Canada. We genotyped 572 individuals using 7 microsatellites loci and found an average F(ST) of 0.127 +/- 0.035 among our 7 sampling sites. We found evidence that major rivers act as important barriers to gene flow at a large scale. We also detected a signal of male-biased gene flow at all scales considered. Our findings highlight the importance of simultaneously taking into account landscape elements and geographic distance, considering the scale at which determinants of genetic structure may act and using the appropriate measures to detect sex-biased dispersal based on the characteristics of the sampling design.


Assuntos
Fluxo Gênico/genética , Sciuridae/genética , Animais , Canadá , Estruturas Genéticas , Genética Populacional , Genótipo , Geografia , Masculino , Repetições de Microssatélites , Ontário , Dinâmica Populacional , Quebeque
20.
Arch Womens Ment Health ; 13(4): 339-45, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20101421

RESUMO

Anxiety and depression during pregnancy increase the risk for an adverse pregnancy outcome and neurodevelopmental problems in the child. The aim of this study was to investigate anxiety and depression in women with a medical disorder of pregnancy compared with control antenatal women, and any association with saliva cortisol. One hundred and twenty pregnant women (60 with a known medical disorder and 60 without, mean gestation 32 weeks) completed five self-rating questionnaires (Spielberger State and Trait Anxiety, Edinburgh Postnatal Depression Scale (EPDS), the Adult Wellbeing Scale and a Life Events Questionnaire). Diurnal saliva samples were obtained from 39 women with a medical disorder and 50 controls for cortisol analysis. The medical disorders group were significantly more anxious and depressed than the controls (mean (SD)) state anxiety 40.0 (11.5) vs. 31.6 (8.8), p = 0.00; trait anxiety 39.4 (9.5) vs. 35.2 (9.2), p = 0.02; adult wellbeing 15.9 (7.5) vs. 12.3 (7.5) p = 0.01; and EPDS 9.6 (5.4) vs. 5.9 (4.8), p = 0.00). There was no difference in the life events scores between the groups. The subgroup of women suffering from hyperemesis gravidarum had particularly high EPDS scores, (16.2 (3), n = 5, p = 0.00) compared with controls. There were no significant differences in the cortisol levels between the groups. Some women with a medical disorder during pregnancy showed considerably elevated levels of anxiety and depression. Health professionals need to be aware that these women need extra psychological support.


Assuntos
Ansiedade/metabolismo , Depressão/metabolismo , Hidrocortisona/metabolismo , Complicações na Gravidez/psicologia , Saliva/química , Adulto , Ansiedade/epidemiologia , Ansiedade/psicologia , Biomarcadores/metabolismo , Estudos de Casos e Controles , Comorbidade , Depressão/epidemiologia , Depressão/psicologia , Feminino , Idade Gestacional , Humanos , Acontecimentos que Mudam a Vida , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/metabolismo , Resultado da Gravidez , Fatores de Risco , Reino Unido/epidemiologia , Adulto Jovem
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