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1.
Proc Natl Acad Sci U S A ; 120(7): e2210953120, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36745812

RESUMO

Opioid use produces enduring associations between drug reinforcement/euphoria and discreet or diffuse cues in the drug-taking environment. These powerful associations can trigger relapse in individuals recovering from opioid use disorder (OUD). Here, we sought to determine whether the epigenetic enzyme, histone deacetylase 5 (HDAC5), regulates relapse-associated behavior in an animal model of OUD. We examined the effects of nucleus accumbens (NAc) HDAC5 on both heroin- and sucrose-seeking behaviors using operant self-administration paradigms. We utilized cre-dependent viral-mediated approaches to investigate the cell-type-specific effects of HDAC5 on heroin-seeking behavior, gene expression, and medium spiny neuron (MSN) cell and synaptic physiology. We found that NAc HDAC5 functions during the acquisition phase of heroin self-administration to limit future relapse-associated behavior. Moreover, overexpressing HDAC5 in the NAc suppressed context-associated and reinstated heroin-seeking behaviors, but it did not alter sucrose seeking. We also found that HDAC5 functions within dopamine D1 receptor-expressing MSNs to suppress cue-induced heroin seeking, and within dopamine D2 receptor-expressing MSNs to suppress drug-primed heroin seeking. Assessing cell-type-specific transcriptomics, we found that HDAC5 reduced expression of multiple ion transport genes in both D1- and D2-MSNs. Consistent with this observation, HDAC5 also produced firing rate depression in both MSN classes. These findings revealed roles for HDAC5 during active heroin use in both D1- and D2-MSNs to limit distinct triggers of drug-seeking behavior. Together, our results suggest that HDAC5 might limit relapse vulnerability through regulation of ion channel gene expression and suppression of MSN firing rates during active heroin use.


Assuntos
Cocaína , Heroína , Camundongos , Animais , Camundongos Transgênicos , Heroína/metabolismo , Heroína/farmacologia , Cocaína/farmacologia , Reforço Psicológico , Comportamento de Procura de Droga/fisiologia , Epigênese Genética , Núcleo Accumbens/fisiologia , Autoadministração
2.
J Am Chem Soc ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842580

RESUMO

Nonribosomal cyclic peptides (NRcPs) are structurally complex natural products and a vital pool of therapeutics, particularly antibiotics. Their structural diversity arises from the ability of the multidomain enzyme assembly lines, nonribosomal peptide synthetases (NRPSs), to utilize bespoke nonproteinogenic amino acids, modify the linear peptide during elongation, and catalyze an array of cyclization modes, e.g., head to tail, side chain to tail. The study and drug development of NRcPs are often limited by a lack of easy synthetic access to NRcPs and their analogues, with selective macrolactamization being a major bottleneck. Herein, we report a generally applicable chemical macrocyclization method of unprecedented speed and selectivity. Inspired by biosynthetic cyclization, it combines the deprotected linear biosynthetic precursor peptide sequence with a highly reactive C-terminus to produce NRcPs and analogues in minutes. The method was applied to several NRcPs of varying sequences, ring sizes, and cyclization modes including rufomycin, colistin, and gramicidin S with comparable success. We thus demonstrate that the linear order of modules in NRPS enzymes that determines peptide sequence encodes the key structural information to produce peptides conformationally biased toward macrocyclization. To fully exploit this conformational bias synthetically, a highly reactive C-terminal acyl azide is also required, alongside carefully balanced pH and solvent conditions. This allows for consistent, facile cyclization of exceptional speed, selectivity, and atom efficiency. This exciting macrolactamization method represents a new enabling technology for the biosynthetic study of NRcPs and their development as therapeutics.

3.
Angew Chem Int Ed Engl ; 63(29): e202403493, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38662909

RESUMO

Cyclopropane fatty acid synthases (CFAS) are a class of S-adenosylmethionine (SAM) dependent methyltransferase enzymes able to catalyse the cyclopropanation of unsaturated phospholipids. Since CFAS enzymes employ SAM as a methylene source to cyclopropanate alkene substrates, they have the potential to be mild and more sustainable biocatalysts for cyclopropanation transformations than current carbene-based approaches. This work describes the characterisation of E. coli CFAS (ecCFAS) and its exploitation in the stereoselective biocatalytic synthesis of cyclopropyl lipids. ecCFAS was found to convert phosphatidylglycerol (PG) to methyl dihydrosterculate 1 with up to 58 % conversion and 73 % ee and the absolute configuration (9S,10R) was established. Substrate tolerance of ecCFAS was found to be correlated with the electronic properties of phospholipid headgroups and for the first time ecCFAS was found to catalyse cyclopropanation of both phospholipid chains to form dicyclopropanated products. In addition, mutagenesis and in silico experiments were carried out to identify the enzyme residues with key roles in catalysis and to provide structural insights into the lipid substrate preference of ecCFAS. Finally, the biocatalytic synthesis of methyl dihydrosterculate 1 and its deuterated analogue was also accomplished combining recombinant ecCFAS with the SAM regenerating AtHMT enzyme in the presence of CH3I and CD3I respectively.


Assuntos
Biocatálise , Ciclopropanos , Escherichia coli , Ciclopropanos/química , Ciclopropanos/metabolismo , Escherichia coli/enzimologia , Escherichia coli/metabolismo , Estereoisomerismo , Metiltransferases/metabolismo , Metiltransferases/química , Ácido Graxo Sintases/metabolismo , Ácido Graxo Sintases/química , Metano/análogos & derivados , Metano/química , Metano/metabolismo , Ácidos Graxos
4.
Addict Biol ; 28(10): e13335, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37753560

RESUMO

Use of addictive substances like cocaine produces enduring associations between the drug experience and cues in the drug-taking environment. In individuals with a substance use disorder (SUD) and attempting to remain abstinent, these powerful drug-cue associations can trigger a return to active drug use, but the molecular mechanisms regulating drug-cue associations remain poorly understood. The activity-regulated cytoskeleton-associated protein (Arc) is induced by cocaine in the nucleus accumbens (NAc), an important brain reward region, but Arc's NAc function in SUD-related behaviour remains unclear. We show here that cocaine self-administration (SA) in rats produced a significant upregulation of Arc protein in both the core and shell subregions of the NAc. Subregion-specific Arc reduction (shRNA) in the medial NAc Shell enhanced both context-associated and cue-reinstated cocaine seeking, but without altering the motivation to work for cocaine, the sensitivity to the reinforcing effects of cocaine or the ability of cocaine priming to reinstate drug seeking. In contrast, we observed no effects of Arc knockdown in the NAc core on any aspect of cocaine SA, extinction or reinstated cocaine seeking, suggesting that Arc functions within the medial NAc shell, but not NAc core, to limit the strength of drug-context and drug-cue associations that promote cocaine-seeking behaviour.

5.
Soc Psychiatry Psychiatr Epidemiol ; 58(1): 105-112, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35648175

RESUMO

PURPOSE: Women diagnosed with non-affective psychosis have a lower general fertility rate (GFR) and age-specific fertility rate (ASFR) than women in the general population. Contemporary data on GFR in this group remain limited, despite substantive changes in prescribing and management. We calculated contemporary estimates of the GFR and ASFR for women diagnosed with non-affective psychosis compared with the general population of women without this diagnosis. METHODS: A population-based design combined routinely collected historical maternity and psychiatric data from two representative areas of Scotland. Women were included from the NHS Grampian or Greater Glasgow and Clyde areas and were aged 15-44 between 2005 and 2013 inclusive. The 'exposed' group had a diagnosis of non-affective psychosis (ICD-10 F20-F29) and was compared to the general population of 'unexposed' women in the same geographical areas. RESULTS: Annual GFR between 2005 and 2013 for women with non-affective psychosis varied from 9.6 to 21.3 live births/1000 women per year in the exposed cohort and 52.7 to 57.8 live births/1000 women per year in the unexposed cohort, a rate ratio (RR) of 0.28 [p < 0.001; 95% CI (0.24, 0.32)]. ASFR for all 5-year age groups was lower in the exposed cohort than amongst unexposed women. CONCLUSION: We highlight continued low fertility rates in women with a diagnosis of non-affective psychosis, despite widespread availability of prolactin-sparing atypical antipsychotics. Accurate estimation of fertility rates remains crucial in developing needs-matched perinatal care for these women. Methodological improvements using routine datasets to investigate perinatal mental health are also urgently needed.


Assuntos
Antipsicóticos , Transtornos Psicóticos , Humanos , Feminino , Gravidez , Coeficiente de Natalidade , Antipsicóticos/uso terapêutico , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/epidemiologia , Transtornos Psicóticos/tratamento farmacológico , Escócia/epidemiologia
6.
J Strength Cond Res ; 37(4): 902-908, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35876437

RESUMO

ABSTRACT: Strand, KL, Ly, AS, Barry, SS, Liscano, JA, Trebotich, TL, Martin-Diala, C, Martin, E, and Signorile, JF. Validity and reliability of the seated medicine ball throw as a measure of upper body power in older women. J Strength Cond Res 37(4): 902-908, 2023-In women, aging is associated with diminishing upper body power, which may increase the risk of falls and fall-related injury; however, the validity and reliability of clinical tests to evaluate upper body power need to be confirmed. The seated medicine ball throw (SMBT) is an upper body performance test used to monitor muscle function among older individuals. The purpose of this study was to evaluate the validity and test-retest reliability of the SMBT in older women. Thirty-five women (age = 75.15 ± 6.39 years) participated in this study. Subjects performed SMBT trials using common ball masses (SMBT 4lb and SMBT 3kg ) over 3 sessions. Familiarization with the SMBT and chest press 1 repetition maximum (CP 1RM ) was provided on the first day. On day 2, subjects repeated the tests, but data were recorded. On day 3, SMBT was retested followed by an evaluation of chest press peak power (CP PP ) values at 30-80% of CP 1RM . Significant correlations ( p ≤ 0.05) were found between the CP PP and SMBT 4lb ( r = 0.775, p < 0.001) and SMBT 3kg ( r = 0.734, p < 0.001), and SMBT distance showed expected declines with age ( r = -0.724 to -0.626, p < 0.001), demonstrating its validity. High reliability between testing days was found, and Bland-Altman plots showed few points that fell outside the limits of agreement. In conclusion, the SMBT is a valid and highly reliable tool that can be used by health professionals to monitor deficits in upper body muscular power to improve treatment protocols in older women.


Assuntos
Força Muscular , Treinamento Resistido , Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Reprodutibilidade dos Testes , Força Muscular/fisiologia , Envelhecimento , Levantamento de Peso , Músculo Esquelético/fisiologia , Teste de Esforço/métodos
7.
J Strength Cond Res ; 37(5): 1124-1130, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36786819

RESUMO

ABSTRACT: Ly, A, Strand, KL, Courtney, KJ, Barry, SS, Liscano, JA, Trebotich, TL, Martin-Diala, C, Martin, E, and Signorile, JF. Reliability of gallon-jug shelf-transfer test power equations in older women. J Strength Cond Res 37(5): 1124-1130, 2023-This study examined the test-retest reliability of the gallon-jug shelf-transfer (GJST) test as a measure of upper-body functional power in older women. Although the validity of the predictive equations for power during the GJST test has been established, for the test to be viable in either a laboratory or clinical environment, between-day and within-day reliability must be established. Thirty-four independently living older women (mean ± SD : 75.0 ± 6.4 years) performed 2 sets of 3 repetitions of the GJST test on 2 days separated by at least 48 hours. Using the established predictive equations, the values for peak power and average power were then computed. Statistical analyses to assess reliability included intraclass correlation coefficient, coefficient of variation (CV), SEM , minimal detectable change (MDC), and Cronbach's α values. Furthermore, Bland-Altman plots evaluated the agreement between the tests. Intraclass correlation coefficient (>0.91, p < 0 001), CV (<8.1%), SEM (<5.94 W), MDC (<14 W), and Cronbach's α (>0.95) indicated excellent reliability. The lines of equality for all Bland-Altman plots fell within the 95% confidence interval of the mean difference, implying that there were no significant differences between tests. Furthermore, bias values were small (<11.15 W), and the limits of agreement (LOA) were within an acceptable range. Based on our statistical analyses, the GJST test is a highly reliable assessment for determining object transfer power for healthy older women.


Assuntos
Nível de Saúde , Humanos , Feminino , Idoso , Reprodutibilidade dos Testes
8.
BMC Infect Dis ; 22(1): 805, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36307776

RESUMO

BACKGROUND: Urinary tract infections are one of the most common infections in primary and secondary care, with the majority of antimicrobial therapy initiated empirically before culture results are available. In some cases, however, over 40% of the bacteria that cause UTIs are resistant to some of the antimicrobials used, yet we do not know how the patient outcome is affected in terms of relapse, treatment failure, progression to more serious illness (bacteraemia) requiring hospitalization, and ultimately death. This study analyzed the current patterns of antimicrobial use for UTI in the community in Scotland, and factors for poor outcomes. OBJECTIVES: To explore antimicrobial use for UTI in the community in Scotland, and the relationship with patient characteristics and antimicrobial resistance in E. coli bloodstream infections and subsequent mortality. METHODS: We included all adult patients in Scotland with a positive blood culture with E. coli growth, receiving at least one UTI-related antimicrobial (amoxicillin, amoxicillin/clavulanic acid, ciprofloxacin, trimethoprim, and nitrofurantoin) between 1st January 2009 and 31st December 2012. Univariate and multivariate logistic regression analysis was performed to understand the impact of age, gender, socioeconomic status, previous community antimicrobial exposure (including long-term use), prior treatment failure, and multi-morbidity, on the occurrence of E. coli bacteraemia, trimethoprim and nitrofurantoin resistance, and mortality. RESULTS: There were 1,093,227 patients aged 16 to 100 years old identified as receiving at least one prescription for the 5 UTI-related antimicrobials during the study period. Antimicrobial use was particularly prevalent in the female elderly population, and 10% study population was on long-term antimicrobials. The greatest predictor for trimethoprim resistance in E. coli bacteraemia was increasing age (OR 7.18, 95% CI 5.70 to 9.04 for the 65 years old and over group), followed by multi-morbidity (OR 5.42, 95% CI 4.82 to 6.09 for Charlson Index 3+). Prior antimicrobial use, along with prior treatment failure, male gender, and higher deprivation were also associated with a greater likelihood of a resistant E. coli bacteraemia. Mortality was significantly associated with both having an E. coli bloodstream infection, and those with resistant growth. CONCLUSION: Increasing age, increasing co-morbidity, lower socioeconomic status, and prior community antibiotic exposure were significantly associated with a resistant E. coli bacteraemia, which leads to increased mortality.


Assuntos
Bacteriemia , Infecções por Escherichia coli , Infecções Urinárias , Adulto , Humanos , Idoso , Masculino , Feminino , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Escherichia coli , Nitrofurantoína , Farmacorresistência Bacteriana , Infecções Urinárias/microbiologia , Infecções por Escherichia coli/microbiologia , Trimetoprima , Bacteriemia/tratamento farmacológico , Bacteriemia/epidemiologia , Amoxicilina , Testes de Sensibilidade Microbiana
9.
Int J Biometeorol ; 66(9): 1915-1927, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35835887

RESUMO

The recent report of the Intergovernmental Panel on Climate Change is stark in its warnings about the changing climate, including future increases in the frequency and intensity of extremely hot weather. The well-established impacts of extreme heat on human health have led to widespread implementation of national and city-wide heat plans for mitigating such impacts. Evaluations of the effectiveness of some heat plans have been published, with previous reviews highlighting key methodological challenges. This article reviews methods used since and that address those challenges, so helping to set an agenda for improving evaluations of heat plans in terms of their effectiveness in reducing heat-health impacts. We examined the reviews that identified the methodological challenges and systematically searched the literature to find evaluations that had since been conducted. We found 11 evaluations. Their methods help address the key challenge of identifying study control groups and address other challenges to a limited extent. For future evaluations, we recommend: utilising recent evaluation methodologies, such as difference-in-differences quasi-experimental designs where appropriate; cross-agency working to utilise data on morbidity and confounders; adoption of a proposed universal heat index; and greater publication of evaluations. More evaluations should assess morbidity outcomes and be conducted in low- and middle-income countries. Evaluations of heat plans globally should employ robust methodologies, as demonstrated in existing studies and potentially transferrable from other fields. Publication of such evaluations will advance the field and thus help address some of the health challenges resulting from our changing climate.


Assuntos
Calor Extremo , Mudança Climática , Previsões , Temperatura Alta , Humanos , Morbidade
10.
Org Biomol Chem ; 19(1): 156-161, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33179689

RESUMO

A mild, chemoselective and sustainable biocatalysed synthesis of sulfoxides has been developed exploiting CALB and using AcOEt with a dual role of more environmentally friendly reaction solvent and enzyme substrate. A series of sulfoxides, including the drug omeprazole, have been synthesised in high yields and with excellent E-factors.

11.
J Am Chem Soc ; 142(37): 15764-15779, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32811149

RESUMO

The cytochromes P450 are heme-dependent enzymes that catalyze many vital reaction processes in the human body related to biodegradation and biosynthesis. They typically act as mono-oxygenases; however, the recently discovered P450 subfamily TxtE utilizes O2 and NO to nitrate aromatic substrates such as L-tryptophan. A direct and selective aromatic nitration reaction may be useful in biotechnology for the synthesis of drugs or small molecules. Details of the catalytic mechanism are unknown, and it has been suggested that the reaction should proceed through either an iron(III)-superoxo or an iron(II)-nitrosyl intermediate. To resolve this controversy, we used stopped-flow kinetics to provide evidence for a catalytic cycle where dioxygen binds prior to NO to generate an active iron(III)-peroxynitrite species that is able to nitrate l-Trp efficiently. We show that the rate of binding of O2 is faster than that of NO and also leads to l-Trp nitration, while little evidence of product formation is observed from the iron(II)-nitrosyl complex. To support the experimental studies, we performed density functional theory studies on large active site cluster models. The studies suggest a mechanism involving an iron(III)-peroxynitrite that splits homolytically to form an iron(IV)-oxo heme (Compound II) and a free NO2 radical via a small free energy of activation. The latter activates the substrate on the aromatic ring, while compound II picks up the ipso-hydrogen to form the product. The calculations give small reaction barriers for most steps in the catalytic cycle and, therefore, predict fast product formation from the iron(III)-peroxynitrite complex. These findings provide the first detailed insight into the mechanism of nitration by a member of the TxtE subfamily and highlight how the enzyme facilitates this novel reaction chemistry.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Compostos Férricos/metabolismo , Nitrocompostos/metabolismo , Ácido Peroxinitroso/metabolismo , Biocatálise , Teoria da Densidade Funcional , Compostos Férricos/química , Modelos Moleculares , Conformação Molecular , Nitrocompostos/química , Ácido Peroxinitroso/química
12.
J Neurosci ; 38(42): 8956-8966, 2018 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-30185459

RESUMO

A single BDNF microinfusion into prelimbic (PrL) cortex immediately after the last cocaine self-administration session decreases relapse to cocaine-seeking. The BDNF effect is blocked by NMDAR antagonists. To determine whether synaptic activity in putative excitatory projection neurons in PrL cortex is sufficient for BDNF's effect on relapse, the PrL cortex of male rats was infused with an inhibitory Designer Receptor Exclusively Activated by Designer Drugs (DREADD) viral vector driven by an αCaMKII promoter. Immediately after the last cocaine self-administration session, rats were injected with clozapine-N-oxide 30 min before an intra-PrL BDNF microinfusion. DREADD-mediated inhibition of the PrL cortex blocked the BDNF-induced decrease in cocaine-seeking after abstinence and cue-induced reinstatement after extinction. Unexpectedly, DREADD inhibition of PrL neurons in PBS-infused rats also reduced cocaine-seeking, suggesting that divergent PrL pathways affect relapse. Next, using a cre-dependent retroviral approach, we tested the ability of DREADD inhibition of PrL projections to the NAc core or the paraventricular thalamic nucleus (PVT) to alter cocaine-seeking in BDNF- and PBS-infused rats. Selective inhibition of the PrL-NAc pathway at the end of cocaine self-administration blocked the BDNF-induced decrease in cocaine-seeking but had no effect in PBS-infused rats. In contrast, selective inhibition of the PrL-PVT pathway in PBS-infused rats decreased cocaine-seeking, and this effect was prevented in BDNF-infused rats. Thus, activity in the PrL-NAc pathway is responsible for the therapeutic effect of BDNF on cocaine-seeking whereas inhibition of activity in the PrL-pPVT pathway elicits a similar therapeutic effect in the absence of BDNF.SIGNIFICANCE STATEMENT The major issue in cocaine addiction is the high rate of relapse. However, the neuronal pathways governing relapse remain unclear. Using a pathway-specific chemogenetic approach, we found that BDNF differentially regulates two key prelimbic pathways to guide long-term relapse. Infusion of BDNF in the prelimbic cortex during early withdrawal from cocaine self-administration decreases relapse that is prevented when neurons projecting from the prelimbic cortex to the nucleus accumbens core are inhibited. In contrast, BDNF restores relapse when neurons projecting from the prelimbic cortex to the posterior paraventricular thalamic nucleus are inhibited. This study demonstrates that two divergent cortical outputs mediate relapse that is regulated in opposite directions by infusing BDNF in the prelimbic cortex during early withdrawal from cocaine.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/fisiologia , Cocaína/administração & dosagem , Comportamento de Procura de Droga/fisiologia , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Animais , Fator Neurotrófico Derivado do Encéfalo/administração & dosagem , Clozapina/administração & dosagem , Clozapina/análogos & derivados , Comportamento de Procura de Droga/efeitos dos fármacos , Masculino , Núcleos da Linha Média do Tálamo/efeitos dos fármacos , Núcleos da Linha Média do Tálamo/fisiologia , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Neurônios/efeitos dos fármacos , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/fisiologia , Córtex Pré-Frontal/efeitos dos fármacos , Ratos Sprague-Dawley
13.
J Am Chem Soc ; 141(1): 216-222, 2019 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-30516965

RESUMO

Cytochromes P450 (CYPs) catalyze various oxidative transformations in drug metabolism, xenobiotic degradation, and natural product biosynthesis. Here we report biochemical, structural, and theoretical studies of TxtC, an unusual bifunctional CYP involved in the biosynthesis of the EPA-approved herbicide thaxtomin A. TxtC was shown to hydroxylate two remote sites within the Phe residue of its diketopiperazine substrate thaxtomin D. The reactions follow a preferred order, with hydroxylation of the α-carbon preceding functionalization of the phenyl group. To illuminate the molecular basis for remote site functionalization, X-ray crystal structures of TxtC in complex with the substrate and monohydroxylated intermediate were determined. Electron density corresponding to a diatomic molecule (probably dioxygen) was sandwiched between the heme iron atom and Thr237 in the TxtC-intermediate structure, providing insight into the mechanism for conversion of the ferrous-dioxygen complex into the reactive ferryl intermediate. The substrate and monohydroxylated intermediate adopted similar conformations in the active site, with the π-face of the phenyl group positioned over the heme iron atom. Docking simulations reproduced this observation and identified a second, energetically similar but conformationally distinct binding mode in which the α-hydrogen of the Phe residue is positioned over the heme prosthetic group. Molecular dynamics simulations confirmed that the α-hydrogen is sufficiently close to the ferryl oxygen atom to be extracted by it and indicated that the two substrate conformations cannot readily interconvert in the active site. These results indicate that TxtC is able to hydroxylate two spatially remote sites by binding distinct conformations of the substrate and monohydroxylated intermediate.


Assuntos
Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/metabolismo , Indóis/metabolismo , Piperazinas/metabolismo , Sítios de Ligação , Biocatálise , Hidroxilação , Indóis/química , Modelos Moleculares , Piperazinas/química , Conformação Proteica , Especificidade por Substrato
14.
Eur J Neurosci ; 50(3): 2477-2491, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30251397

RESUMO

Drug use leads to addiction in some individuals, but the underlying brain mechanisms that control the transition from casual drug use to an intractable substance use disorder (SUD) are not well understood. Gene x environment interactions such as the frequency of drug use and the type of substance used likely to promote maladaptive plastic changes in brain regions that are critical for controlling addiction-related behavior. Epigenetics encompasses a broad spectrum of mechanisms important for regulating gene transcription that are not dependent on changes in DNA base pair sequences. This review focuses on the proteins and complexes contributing to epigenetic modifications in the nucleus accumbens (NAc) following drug experience. We discuss in detail the three major mechanisms: histone acetylation and deacetylation, histone methylation, and DNA methylation. We discuss how drug use alters the regulation of the associated proteins regulating these processes and highlight how experimental manipulations of these proteins in the NAc can alter drug-related behaviors. Finally, we discuss the ways that histone modifications and DNA methylation coordinate actions by recruiting large epigenetic enzyme complexes to aid in transcriptional repression. Targeting these multiprotein epigenetic enzyme complexes - and the individual proteins that comprise them - might lead to effective therapeutics to reverse or treat SUDs in patients.


Assuntos
Encéfalo/metabolismo , Epigênese Genética/fisiologia , Transtornos Relacionados ao Uso de Substâncias/genética , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Animais , Cromatina/genética , Cromatina/metabolismo , Metilação de DNA/fisiologia , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Humanos , Transtornos Relacionados ao Uso de Substâncias/psicologia
15.
Int J Behav Nutr Phys Act ; 15(1): 60, 2018 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-29954449

RESUMO

BACKGROUND: Obesity is a major public health concern requiring innovative interventions that support people to lose weight and keep it off long term. However, weight loss maintenance remains a challenge and is under-researched, particularly in men. The Football Fans in Training (FFIT) programme engages men in weight management through their interest in football, and encourages them to incorporate small, incremental physical activity and dietary changes into daily life to support long-term weight loss maintenance. In 2011/12, a randomised controlled trial (RCT) of FFIT demonstrated effectiveness and cost-effectiveness at 12 months. The current study aimed to investigate long-term maintenance of weight loss, behavioural outcomes and lifetime cost-effectiveness following FFIT. METHODS: A longitudinal cohort study comprised 3.5-year follow-up of the 747 FFIT RCT participants. Men aged 35-65 years, BMI ≥ 28 kg/m2 at RCT baseline who consented to long-term follow-up (n = 665) were invited to participate: those in the FFIT Follow Up Intervention group (FFIT-FU-I) undertook FFIT in 2011 during the RCT; the FFIT Follow Up Comparison group (FFIT-FU-C) undertook FFIT in 2012 under routine (non-research) conditions. The primary outcome was objectively-measured weight loss (from baseline) at 3.5 years. Secondary outcomes included changes in self-reported physical activity and diet at 3.5 years. Cost-effectiveness was estimated at 3.5 years and over participants' lifetime. RESULTS: Of 665 men invited, 488 (73%; 65% of the 747 RCT participants) attended 3.5-year measurements. The FFIT-FU-I group sustained a mean weight loss of 2.90 kg (95% CI 1.78, 4.02; p < 0.001) 3.5 years after starting FFIT; 32.2% (75/233) weighed ≥5% less than baseline. The FFIT-FU-C group had lost 2.71 kg (1.65, 3.77; p < 0.001) at the 3.5-year measurements (2.5 years after starting FFIT); 31.8% (81/255) weighed ≥5% less than baseline. There were significant sustained improvements in self-reported physical activity and diet in both groups. The estimated incremental cost-effectiveness of FFIT was £10,700-£15,300 per QALY gained at 3.5 years, and £1790-£2200 over participants' lifetime. CONCLUSIONS: Participation in FFIT under research and routine conditions leads to long-term weight loss and improvements in physical activity and diet. Investment in FFIT is likely to be cost-effective as part of obesity management strategies in countries where football is popular. TRIAL REGISTRATION: ISRCTN32677491 , 20 October 2011.


Assuntos
Avaliação de Programas e Projetos de Saúde/métodos , Futebol , Programas de Redução de Peso/economia , Programas de Redução de Peso/métodos , Adulto , Idoso , Índice de Massa Corporal , Estudos de Coortes , Análise Custo-Benefício , Dieta , Exercício Físico , Seguimentos , Promoção da Saúde/métodos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Tempo , Resultado do Tratamento
17.
Behav Cogn Psychother ; 45(3): 209-224, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28166849

RESUMO

BACKGROUND: Psychological therapy services are often required to demonstrate their effectiveness and are implementing systematic monitoring of patient progress. A system for measuring patient progress might usefully 'inform supervision' and help patients who are not progressing in therapy. AIMS: To examine if continuous monitoring of patient progress through the supervision process was more effective in improving patient outcomes compared with giving feedback to therapists alone in routine NHS psychological therapy. METHOD: Using a stepped wedge randomized controlled design, continuous feedback on patient progress during therapy was given either to the therapist and supervisor to be discussed in clinical supervison (MeMOS condition) or only given to the therapist (S-Sup condition). If a patient failed to progress in the MeMOS condition, an alert was triggered and sent to both the therapist and supervisor. Outcome measures were completed at beginning of therapy, end of therapy and at 6-month follow-up and session-by-session ratings. RESULTS: No differences in clinical outcomes of patients were found between MeMOS and S-Sup conditions. Patients in the MeMOS condition were rated as improving less, and more ill. They received fewer therapy sessions. CONCLUSIONS: Most patients failed to improve in therapy at some point. Patients' recovery was not affected by feeding back outcomes into the supervision process. Therapists rated patients in the S-Sup condition as improving more and being less ill than patients in MeMOS. Those patients in MeMOS had more complex problems.


Assuntos
Feedback Formativo , Psicoterapia/métodos , Adulto , Feminino , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Resultado do Tratamento
18.
J Appl Res Intellect Disabil ; 30(2): 383-394, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26918272

RESUMO

BACKGROUND: Day services for people with intellectual disabilities are experiencing a global paradigm shift towards innovative person-centred models of care. This study maps changing trends in day service utilization to highlight how policy, emergent patterns and demographic trends influence service delivery. METHODS: National intellectual disability data (1998-2013) were analysed using WINPEPI software and mapped using QGIS Geographic Information System. RESULTS: Statistically significant changes indicated fewer people availing of day services as a proportion of the general population; more males; fewer people aged <35; a doubling in person-centred plans; and an emerging urban/rural divide. Day services did not change substantially and often did not reflect demand. CONCLUSIONS: Emergent trends can inform future direction of disability services. Government funds should support individualized models, more adaptive to changing trends. National databases need flexibility to respond to policy and user demands. Future research should focus on day service utilization of younger people and the impact of rurality on service availability, utilization, quality and migration.

19.
Biochem Soc Trans ; 44(3): 738-44, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27284036

RESUMO

Catalysts are a vital part of synthetic chemistry. However, there are still many important reactions for which catalysts have not been developed. The use of enzymes as biocatalysts for synthetic chemistry is growing in importance due to the drive towards sustainable methods for producing both bulk chemicals and high value compounds such as pharmaceuticals, and due to the ability of enzymes to catalyse chemical reactions with excellent stereoselectivity and regioselectivity. Such challenging transformations are a common feature of natural product biosynthetic pathways. In this mini-review, we discuss the potential to use biosynthetic pathways as a starting point for biocatalyst discovery. We introduce the reader to natural product assembly and tailoring, then focus on four classes of enzyme that catalyse C─H bond activation reactions to functionalize biosynthetic precursors. Finally, we briefly discuss the challenges involved in novel enzyme discovery.


Assuntos
Produtos Biológicos/metabolismo , Vias Biossintéticas , Enzimas/metabolismo , Biologia Sintética/métodos
20.
Lancet ; 383(9919): 796-806, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24290404

RESUMO

BACKGROUND: Pelvic organ prolapse is common and is strongly associated with childbirth and increasing age. Women with prolapse are often advised to do pelvic floor muscle exercises, but evidence supporting the benefits of such exercises is scarce. We aimed to establish the effectiveness of one-to-one individualised pelvic floor muscle training for reducing prolapse symptoms. METHODS: We did a parallel-group, multicentre, randomised controlled trial at 23 centres in the UK, one in New Zealand, and one in Australia, between June 22, 2007, and April 9, 2010. Female outpatients with newly-diagnosed, symptomatic stage I, II, or III prolapse were randomly assigned (1:1), by remote computer allocation with minimsation, to receive an individualised programme of pelvic floor muscle training or a prolapse lifestyle advice leaflet and no muscle training (control group). Outcome assessors, and investigators who were gynaecologists at trial sites, were masked to group allocation; the statistician was masked until after data analysis. Our primary endpoint was participants' self-report of prolapse symptoms at 12 months. Analysis was by intention-to-treat analysis. This trial is registered, number ISRCTN35911035. FINDINGS: 447 eligible patients were randomised to the intervention group (n=225) or the control group (n=222). 377 (84%) participants completed follow-up for questionnaires at 6 months and 295 (66%) for questionnaires at 12 months. Women in the intervention group reported fewer prolapse symptoms (ie, a significantly greater reduction in the pelvic organ prolapse symptom score [POP-SS]) at 12 months than those in the control group (mean reduction in POP-SS from baseline 3.77 [SD 5.62] vs 2.09 [5.39]; adjusted difference 1.52, 95% CI 0.46-2.59; p=0.0053). Findings were robust to missing data. Eight adverse events (six vaginal symptoms, one case of back pain, and one case of abdominal pain) and one unexpected serious adverse event, all in women from the intervention group, were regarded as unrelated to the intervention or to participation in the study. INTERPRETATION: One-to-one pelvic floor muscle training for prolapse is effective for improvement of prolapse symptoms. Long-term benefits should be investigated, as should the effects in specific subgroups. FUNDING: Chief Scientist Office of the Scottish Government Health and Social Care Directorates, New Zealand Lottery Board, and National Health and Medical Research Council (Australia).


Assuntos
Terapia por Exercício/métodos , Prolapso de Órgão Pélvico/terapia , Assistência Ambulatorial , Feminino , Humanos , Pessoa de Meia-Idade , Diafragma da Pelve , Medicina de Precisão/métodos , Resultado do Tratamento
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