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1.
Nature ; 628(8007): 282-286, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38570690

RESUMEN

Polyatomic molecules have rich structural features that make them uniquely suited to applications in quantum information science1-3, quantum simulation4-6, ultracold chemistry7 and searches for physics beyond the standard model8-10. However, a key challenge is fully controlling both the internal quantum state and the motional degrees of freedom of the molecules. Here we demonstrate the creation of an optical tweezer array of individual polyatomic molecules, CaOH, with quantum control of their internal quantum state. The complex quantum structure of CaOH results in a non-trivial dependence of the molecules' behaviour on the tweezer light wavelength. We control this interaction and directly and non-destructively image individual molecules in the tweezer array with a fidelity greater than 90%. The molecules are manipulated at the single internal quantum state level, thus demonstrating coherent state control in a tweezer array. The platform demonstrated here will enable a variety of experiments using individual polyatomic molecules with arbitrary spatial arrangement.

2.
Int J Geriatr Psychiatry ; 39(2): e6062, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38380892

RESUMEN

OBJECTIVES: The COVID-19 pandemic and accompanying public health measures exacerbated many known risk factors for depression, while also increasing numerous health-related stressors for people with stroke history. Using a large longitudinal sample of older adults, the current study examined the prevalence of incident and recurrent depression among participants with stroke history, and also identified factors that were associated with depression during the pandemic among this population. METHODS: Data came from four waves of the Canadian Longitudinal Study on Aging's (CLSA) comprehensive cohort (n = 577 with stroke history; 46.1% female; 20.8% immigrants; mean age = 74.56 SD = 9.19). The outcome of interest was a positive screen for depression, based on the CES-D-10, collected during the 2020 CLSA COVID autumn questionnaire. Bivariate and multivariate logistic regression analyses were conducted to identify factors that were associated with depression. RESULTS: Approximately 1 in 2 (49.5%) participants with stroke history and a history of depression experienced a recurrence of depression early in the pandemic. Among those without a history of depression, approximately 1 in 7 (15.0%) developed depression for the first time during this period. The risk of depression was higher among immigrants, those who were lonely, those with functional limitations, and those who experienced COVID-19 related stressors, such as increased family issues, difficulty accessing healthcare, and becoming ill or having a loved one become ill or die during the pandemic. CONCLUSIONS: Interventions that target those with stroke history, both with and without a history of depression, are needed to buffer against the stressors of the COVID-19 pandemic and support the mental health of this population.


Asunto(s)
COVID-19 , Accidente Cerebrovascular , Humanos , Femenino , Anciano , Masculino , COVID-19/epidemiología , Canadá/epidemiología , Depresión/epidemiología , Estudios Longitudinales , Pandemias , Envejecimiento , Accidente Cerebrovascular/epidemiología
3.
Lancet ; 399(10342): 2212-2225, 2022 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-35691324

RESUMEN

BACKGROUND: Vaccination of children and young people against SARS-CoV-2 is recommended in some countries. Scarce data have been published on immune responses induced by COVID-19 vaccines in people younger than 18 years compared with the same data that are available in adults. METHODS: COV006 is a phase 2, single-blind, randomised, controlled trial of ChAdOx1 nCoV-19 (AZD1222) in children and adolescents at four trial sites in the UK. Healthy participants aged 6-17 years, who did not have a history of chronic respiratory conditions, laboratory-confirmed COVID-19, or previously received capsular group B meningococcal vaccine (the control), were randomly assigned to four groups (4:1:4:1) to receive two intramuscular doses of 5 × 1010 viral particles of ChAdOx1 nCoV-19 or control, 28 days or 84 days apart. Participants, clinical investigators, and the laboratory team were masked to treatment allocation. Study groups were stratified by age, and participants aged 12-17 years were enrolled before those aged 6-11 years. Due to the restrictions in the use of ChAdOx1 nCoV-19 in people younger than 30 years that were introduced during the study, only participants aged 12-17 years who were randomly assigned to the 28-day interval group had received their vaccinations at the intended interval (day 28). The remaining participants received their second dose at day 112. The primary outcome was assessment of safety and tolerability in the safety population, which included all participants who received at least one dose of the study drug. The secondary outcome was immunogenicity, which was assessed in participants who were seronegative to the nucleocapsid protein at baseline and received both prime and boost vaccine. This study is registered with ISRCTN (15638344). FINDINGS: Between Feb 15 and April 2, 2021, 262 participants (150 [57%] participants aged 12-17 years and 112 [43%] aged 6-11 years; due to the change in the UK vaccination policy, the study terminated recruitment of the younger age group before the planned number of participants had been enrolled) were randomly assigned to receive vaccination with two doses of either ChAdOx1 nCoV-19 (n=211 [n=105 at day 28 and n=106 at day 84]) or control (n=51 [n=26 at day 28 and n=25 at day 84]). One participant in the ChAdOx1 nCoV-19 day 28 group in the younger age bracket withdrew their consent before receiving a first dose. Of the participants who received ChAdOx1 nCoV-19, 169 (80%) of 210 participants reported at least one solicited local or systemic adverse event up to 7 days following the first dose, and 146 (76%) of 193 participants following the second dose. No serious adverse events related to ChAdOx1 nCoV-19 administration were recorded by the data cutoff date on Oct 28, 2021. Of the participants who received at least one dose of ChAdOx1 nCoV-19, there were 128 unsolicited adverse events up to 28 days after vaccination reported by 83 (40%) of 210 participants. One participant aged 6-11 years receiving ChAdOx1 nCoV-19 reported a grade 4 fever of 40·2°C on day 1 following first vaccination, which resolved within 24 h. Pain and tenderness were the most common local solicited adverse events for all the ChAdOx1 nCoV-19 and capsular group B meningococcal groups following both doses. Of the 242 participants with available serostatus data, 14 (6%) were seropositive at baseline. Serostatus data were not available for 20 (8%) of 262 participants. Among seronegative participants who received ChAdOx1 nCoV-19, anti-SARS-CoV-2 IgG and pseudoneutralising antibody titres at day 28 after the second dose were higher in participants aged 12-17 years with a longer interval between doses (geometric means of 73 371 arbitrary units [AU]/mL [95% CI 58 685-91 733] and 299 half-maximal inhibitory concentration [IC50; 95% CI 230-390]) compared with those aged 12-17 years who received their vaccines 28 days apart (43 280 AU/mL [95% CI 35 852-52 246] and 150 IC50 [95% CI 116-194]). Humoral responses were higher in those aged 6-11 years than in those aged 12-17 years receiving their second dose at the same 112-day interval (geometric mean ratios 1·48 [95% CI 1·07-2·07] for anti-SARS-CoV-2 IgG and 2·96 [1·89-4·62] for pseudoneutralising antibody titres). Cellular responses peaked after a first dose of ChAdOx1 nCoV-19 across all age and interval groups and remained above baseline after a second vaccination. INTERPRETATION: ChAdOx1 nCoV-19 is well tolerated and immunogenic in children aged 6-17 years, inducing concentrations of antibody that are similar to those associated with high efficacy in phase 3 studies in adults. No safety concerns were raised in this trial. FUNDING: AstraZeneca and the UK Department of Health and Social Care through the UK National Institute for Health and Care Research.


Asunto(s)
COVID-19 , Vacunas Meningococicas , Adolescente , Adulto , Anticuerpos Antivirales , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , ChAdOx1 nCoV-19 , Niño , Método Doble Ciego , Humanos , Inmunoglobulina G , SARS-CoV-2 , Método Simple Ciego
4.
Respir Res ; 24(1): 226, 2023 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-37742015

RESUMEN

BACKGROUND: Small airways disease plays a key role in the pathogenesis of chronic obstructive pulmonary disease (COPD) and is a major cause of obstruction; therefore, it is a critical pharmacotherapy target. This study evaluated lung deposition of two inhaled corticosteroid (ICS)/long-acting ß2-agonist/long-acting muscarinic antagonist single-inhaler triple therapies using in silico functional respiratory imaging (FRI). Deposition was assessed using real-world inhalation profiles simulating everyday use where optimal inhalation may be compromised. METHODS: Three-dimensional airway models were produced from 20 patients with moderate-to-very severe COPD. Total, central, and regional small airways deposition as a percentage of delivered dose of budesonide/glycopyrronium/formoterol fumarate dihydrate (BGF) 160/7.2/5 µg per actuation and fluticasone furoate/umeclidinium/vilanterol (FF/UM/VI) 100/62.5/25 µg were evaluated using in silico FRI based on in vitro aerodynamic particle size distributions of each device. Simulations were performed using multiple inhalation profiles of varying durations and flow rates representing patterns suited for a pressurized metered-dose inhaler or dry-powder inhaler (four for BGF, two for FF/UM/VI, with one common profile). For the common profile, deposition for BGF versus FF/UM/VI was compared post-hoc using paired t-tests. RESULTS: Across inhalation profiles, mean total lung deposition was consistently higher with BGF (47.0-54.1%) versus FF/UM/VI (20.8-22.7%) and for each treatment component, with greater deposition for BGF also seen in the central large airways. Mean regional small airways deposition was also greater across inhalation profiles with BGF (16.9-23.6%) versus FF/UM/VI (6.8-8.7%) and for each treatment component. For the common profile, total, central, and regional small airways deposition were significantly greater for BGF versus FF/UM/VI (nominal p < 0.001), overall and for treatment components; notably, regional small airways deposition of the ICS components was approximately five-fold greater with budesonide versus fluticasone furoate (16.1% vs. 3.3%). CONCLUSIONS: BGF was associated with greater total, central, and small airways deposition for all components versus FF/UM/VI. Importantly, using an identical inhalation profile, there was an approximately five-fold difference in small airways deposition for the ICS components, with only a small percentage of the ICS from FF/UM/VI reaching the small airways. Further research is needed to understand if the enhanced delivery of BGF translates to clinical benefits.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica , Humanos , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Fluticasona , Budesonida , Inhaladores de Polvo Seco , Pulmón/diagnóstico por imagen
5.
Inorg Chem ; 62(48): 19758-19770, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-37972340

RESUMEN

Selective halogenation is necessary for a range of fine chemical applications, including the development of therapeutic drugs. While synthetic processes to achieve C-H halogenation require harsh conditions, enzymes such as nonheme iron halogenases carry out some types of C-H halogenation, i.e., chlorination or bromination, with ease, while others, i.e., fluorination, have never been observed in natural or engineered nonheme iron enzymes. Using density functional theory and correlated wave function theory, we investigate the differences in structural and energetic preferences of the smaller fluoride and the larger chloride or bromide intermediates throughout the catalytic cycle. Although we find that the energetics of rate-limiting hydrogen atom transfer are not strongly impacted by fluoride substitution, the higher barriers observed during the radical rebound reaction for fluoride relative to chloride and bromide contribute to the difficulty of C-H fluorination. We also investigate the possibility of isomerization playing a role in differences in reaction selectivity, and our calculations reveal crucial differences in terms of isomer energetics of the key ferryl intermediate between fluoride and chloride/bromide intermediates. While formation of monodentate isomers believed to be involved in selective catalysis is shown for chloride and bromide intermediates, we find that formation of the fluoride monodentate intermediate is not possible in our calculations, which lack additional stabilizing interactions with the greater protein environment. Furthermore, the shorter Fe-F bonds are found to increase isomerization reaction barriers, suggesting that incorporation of residues that form a halogen bond with F and elongate Fe-F bonds could make selective C-H fluorination possible in nonheme iron halogenases. Our work highlights the differences between the fluoride and chloride/bromide intermediates and suggests potential steps toward engineering nonheme iron halogenases to enable selective C-H fluorination.


Asunto(s)
Fluoruros , Hierro , Hierro/química , Bromuros , Cloruros , Halogenación
6.
Stroke ; 53(3): 728-738, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35143325

RESUMEN

BACKGROUND: A small randomized controlled trial suggested that dabigatran may be as effective as warfarin in the treatment of cerebral venous thrombosis (CVT). We aimed to compare direct oral anticoagulants (DOACs) to warfarin in a real-world CVT cohort. METHODS: This multicenter international retrospective study (United States, Europe, New Zealand) included consecutive patients with CVT treated with oral anticoagulation from January 2015 to December 2020. We abstracted demographics and CVT risk factors, hypercoagulable labs, baseline imaging data, and clinical and radiological outcomes from medical records. We used adjusted inverse probability of treatment weighted Cox-regression models to compare recurrent cerebral or systemic venous thrombosis, death, and major hemorrhage in patients treated with warfarin versus DOACs. We performed adjusted inverse probability of treatment weighted logistic regression to compare recanalization rates on follow-up imaging across the 2 treatments groups. RESULTS: Among 1025 CVT patients across 27 centers, 845 patients met our inclusion criteria. Mean age was 44.8 years, 64.7% were women; 33.0% received DOAC only, 51.8% received warfarin only, and 15.1% received both treatments at different times. During a median follow-up of 345 (interquartile range, 140-720) days, there were 5.68 recurrent venous thrombosis, 3.77 major hemorrhages, and 1.84 deaths per 100 patient-years. Among 525 patients who met recanalization analysis inclusion criteria, 36.6% had complete, 48.2% had partial, and 15.2% had no recanalization. When compared with warfarin, DOAC treatment was associated with similar risk of recurrent venous thrombosis (aHR, 0.94 [95% CI, 0.51-1.73]; P=0.84), death (aHR, 0.78 [95% CI, 0.22-2.76]; P=0.70), and rate of partial/complete recanalization (aOR, 0.92 [95% CI, 0.48-1.73]; P=0.79), but a lower risk of major hemorrhage (aHR, 0.35 [95% CI, 0.15-0.82]; P=0.02). CONCLUSIONS: In patients with CVT, treatment with DOACs was associated with similar clinical and radiographic outcomes and favorable safety profile when compared with warfarin treatment. Our findings need confirmation by large prospective or randomized studies.


Asunto(s)
Anticoagulantes/administración & dosificación , Dabigatrán/administración & dosificación , Trombosis Intracraneal/tratamiento farmacológico , Trombosis de la Vena/tratamiento farmacológico , Warfarina/administración & dosificación , Administración Oral , Adulto , Anciano , Anticoagulantes/efectos adversos , Dabigatrán/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Warfarina/efectos adversos
7.
Nicotine Tob Res ; 24(7): 1020-1027, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-34893915

RESUMEN

BACKGROUND: The number of countries mandating a nicotine addiction warning label ("warnings") on nicotine vaping products (NVPs) has been increasing. This study examined associations between noticing NVP warnings, perceptions of NVPs, and intentions to use NVPs. AIM AND METHODS: Cross-sectional analysis of 12 619 adult NVP users, cigarette smokers, concurrent users of both cigarettes and NVPs, and quitters who participated in the 2018 International Tobacco Control (ITC) Project Four Country Smoking and Vaping Survey (England, Australia, Canada, USA). Logistic regression analyses examined associations between noticing warnings in the past 30 days and perceptions of nicotine harm, NVP harm relative to cigarettes, and NVP addictiveness relative to cigarettes. Associations were also explored between noticing warnings and intentions to use NVPs. RESULTS: Noticing warnings was higher among NVP users (18.8%) than nonusers (2.1%). Noticing warnings was associated with perceiving nicotine to pose little or no harm to health among NVP users, but there was no association among nonusers. There was little evidence of an association between noticing warnings and perceptions of NVP harms relative to smoking among NVP users and non-users. Noticing warnings was associated with perceiving NVPs as less addictive than cigarettes among nonusers but not NVP users. Among exclusive smokers, noticing warnings was associated with intending to start using NVPs. Among NVP users, there was little evidence of an association between noticing warnings and intentions to continue using/stopping NVPs. CONCLUSIONS: Noticing NVP warnings was not associated with increased NVP and nicotine harm perceptions or decreased intentions to use NVPs among adult smokers and vapers. IMPLICATIONS: Our findings suggest that noticing NVP warnings may not influence NVP risk perceptions or deter NVP use among adult smokers and vapers. Future research should investigate the impact of warnings on youth and adults who have never smoked or vaped.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Vapeo , Adolescente , Adulto , Estudios Transversales , Humanos , Nicotina/efectos adversos , Fumadores , Fumar/efectos adversos , Vapeo/efectos adversos
8.
Tob Control ; 31(1): 107-111, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33115961

RESUMEN

BACKGROUND AND AIMS: In May 2017, black-and-white text nicotine addiction warning labels ('warnings') and health and safety leaflets ('leaflets') became mandatory for nicotine vaping products (NVPs) in England, in accordance with the European Union's Tobacco Products Directive. We compared changes over time in noticing warnings and leaflets, recall of warnings about nicotine and concerns about using NVP due to noticing warnings in England, compared with Canada, the US and Australia, where no warnings and leaflets were mandated. DESIGN: 19 005 adult (aged 18+) NVP users, smokers and quitters of cigarettes and NVP from the 2016 and 2018 International Tobacco Control Four Country Smoking and Vaping Surveys in England, Canada, the US and Australia, recruited via probability and non-probability sampling. FINDINGS: Noticing warnings increased in England from 4.9% (2016) to 9.4% (2018) (adjusted OR/AOR=1.64, 95% CI=1.15-2.36); this change was larger than changes in Canada (AOR=2.51, 95% CI=1.71-3.69) and the US (AOR=2.22, 95% CI=1.45-3.39). Recall of a nicotine warning increased in England from 86% (2016) to 94.9% (2018) (AOR=5.50, 95% CI=1.57-19.27) but not significantly elsewhere. Noticing leaflets increased in England from 14.6% (2016) to 19.1% (2018) (AOR=1.42, 95% CI=1.15-1.74); this change was larger than in Canada (AOR=1.42, 95% CI=1.12-1.79), the US (AOR=1.55, 95% CI=1.17-2.06) and Australia (AOR=1.51, 95% CI=1.02-2.22). Among those noticing warnings, concern about NVP use did not change significantly between 2016 and 2018 (all countries p>0.081). CONCLUSIONS: Introduction of mandatory NVP warnings and leaflets in England was associated with small increases in noticing them but not with changes in concerns about NVP use.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Vapeo , Adulto , Canadá/epidemiología , Humanos , Nicotina , Fumadores , Fumar/efectos adversos , Fumar/epidemiología , Fumar Tabaco , Vapeo/efectos adversos
9.
Biophys J ; 120(11): 2181-2191, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33798566

RESUMEN

Long interspersed nuclear element-1 (L1) is a retrotransposable element that autonomously replicates in the human genome, resulting in DNA damage and genomic instability. Activation of L1 in senescent cells triggers a type I interferon response and age-associated inflammation. Two open reading frames encode an ORF1 protein functioning as messenger RNA chaperone and an ORF2 protein providing catalytic activities necessary for retrotransposition. No function has been identified for the conserved, disordered N-terminal region of ORF1. Using microscopy and NMR spectroscopy, we demonstrate that ORF1 forms liquid droplets in vitro in a salt-dependent manner and that interactions between its N-terminal region and coiled-coil domain are necessary for phase separation. Mutations disrupting blocks of charged residues within the N-terminus impair phase separation, whereas some mutations within the coiled-coil domain enhance phase separation. Demixing of the L1 particle from the cytosol may provide a mechanism to protect the L1 transcript from degradation.


Asunto(s)
Elementos de Nucleótido Esparcido Largo , Chaperonas Moleculares , Humanos , Elementos de Nucleótido Esparcido Largo/genética , Sistemas de Lectura Abierta , Dominios Proteicos , ARN Mensajero
10.
Int J Aging Hum Dev ; 93(4): 986-1011, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-32757618

RESUMEN

Drawing from a sociocultural life course perspective, this study examines the linkages between two age-related family transitions: young adult children leaving home and parental retirement. A sample of 580 ethnically diverse parents aged 50+ with at least one adult child aged 19-35 living in Metro Vancouver, British Columbia, Canada, was used in this study based on four cultural groups: British-, Chinese-, Persian/Iranian-, or South Asian-Canadian. Separate survival analyses are used to predict the timing of, and associations between children's leaving home and parents' retirement. Later timing of adult children's leaving home is associated with delays in retirement of parents and is influenced by a number of predictors. Main and interaction effects were supported for ethnicity, where belonging to the Persian/Iranian ethnic group (compared to British) delays home leaving, and belonging to Persian/Iranian and South Asian ethnic groups (compared to British) delays retirement timing.


Asunto(s)
Padres , Jubilación , Hijos Adultos , Colombia Británica , Humanos , Irán
11.
Bull World Health Organ ; 98(7): 458-466, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32742031

RESUMEN

OBJECTIVE: To investigate international consumption patterns of child-appropriate oral formulations of antibiotics by formulation type, with a focus on dispersible tablets, using data from a global sales database. METHOD: Antibiotic sales data for 2015 covering 74 countries and regional country groups were obtained from the MIDAS® pharmaceutical sales database, which includes samples of pharmacy wholesalers and retailers. The focus was on sales of child-appropriate oral formulations of Access antibiotics in the 2017 World Health Organization's WHO Model list of essential medicines for children. Sales volumes are expressed using a standard unit (i.e. one tablet, capsule, ampoule or vial or 5 mL of liquid). Sales were analysed by antibiotic, WHO region and antibiotic formulation. FINDINGS: Globally, 17.7 billion standard units of child-appropriate oral antibiotic formulations were sold in 2015, representing 24% of total antibiotic sales of 74.4 billion units (both oral and parenteral) in the database. The top five child-appropriate Access antibiotics by sales volume were amoxicillin, amoxicillin with clavulanic acid, trimethoprim-sulfamethoxazole, cefalexin and ampicillin. The proportion of the top five sold for use as a syrup varied between 42% and 99%. Dispersible tablets represented only 22% of all child-appropriate oral formulation sales and made up only 15% of sales of 10 selected Access antibiotics on the model list for children. CONCLUSION: Globally most child-appropriate oral antibiotics were not sold as dispersible tablets in 2015, as recommended by WHO. There is a clear need for novel solid forms of antibiotics suitable for use in children.


Asunto(s)
Antibacterianos/uso terapéutico , Utilización de Medicamentos/estadística & datos numéricos , Administración Oral , Niño , Preescolar , Comercio , Bases de Datos Factuales , Humanos , Lactante , Comprimidos
12.
Horm Behav ; 113: 13-20, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31054274

RESUMEN

Anabolic-androgenic steroids (AAS) are drugs of abuse that impair behavior and cognition. In a rodent model of AAS abuse, testosterone-treated male rats expend more physical effort, by repeatedly pressing a lever for a large reward in an operant discounting task. However, since modern society prioritizes cognitive over physical effort, it is important to determine if AAS limit cognitive effort. Here we tested the effects of AAS on a novel cognitive-effort discounting task. Each operant chamber had 3 nose-pokes, opposite 2 levers and a pellet dispenser. Rats pressed a lever to illuminate 1 nose-poke; they responded in the illuminated nose-poke to receive sugar pellets. For the 'easy' lever, the light remained on for 1 s, and a correct response earned 1 pellet. For the 'hard' lever, the light duration decreased from 1 s to 0.1 s across 5 blocks of trials, and a correct response earned 4 pellets. As the duration of the nose-poke light decreased, all rats decreased their choice of the hard lever in a modest discounting curve. Task accuracy also decreased significantly across the 5 blocks of trials. However, there was no effect of testosterone on choice of the hard lever or task accuracy. Antagonism of dopamine D1 or D2 receptors had no effect on lever choice or task accuracy. However, serotonin depletion significantly decreased preference for the hard lever, and impaired task accuracy. Thus, physical effort discounting depends on dopamine activity, while cognitive effort discounting task is sensitive to serotonin. AAS impair physical effort discounting, but not cognitive effort discounting.


Asunto(s)
Anabolizantes/farmacología , Andrógenos/farmacología , Cognición/efectos de los fármacos , Condicionamiento Operante/efectos de los fármacos , Esteroides/farmacología , Animales , Dopamina/farmacología , Dopamina/fisiología , Antagonistas de Dopamina/farmacología , Masculino , Ratas , Ratas Long-Evans , Receptores de Dopamina D2/efectos de los fármacos , Receptores de Dopamina D2/metabolismo , Recompensa , Testosterona/farmacología
13.
14.
Nephrology (Carlton) ; 24(3): 308-315, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29717528

RESUMEN

AIM: While the prevalence of end stage kidney disease in New Zealand (NZ) is well defined, the prevalence of chronic kidney disease (CKD) in NZ is unknown. To estimate the prevalence of and risk factors for CKD in the southern region of New Zealand. METHODS: A retrospective electronic health record cohort study using data from the Southern Primary Care register covering 94% of the population. Patients, 20 years or older were identified and linked to laboratory results for serum creatinine and urinary albumin excretion. Chronic kidney disease was defined as an estimated glomerular filtration rate of less than 60 mL/min per 1.73 m2 (G3-5) or the presence of albuminuria of greater than 3 mg/mmol (A2-3). Diabetes was identified from a national virtual diabetes database. From this, we estimated the prevalence of CKD by age, gender, ethnicity, deprivation and the presence of diabetes mellitus. RESULTS: Of a total adult population of 211 980, 159 799 had a serum creatinine checked and 27 905 had an estimate of albuminuria. The estimated prevalence of CKD was 11.8%. 6.3% of total population had CKD stage G3a, 2.4% G3b, 0.8% G4, 0.2% G5, 1.8% A2 albuminuria and 0.3% A3 albuminuria. Increasing age, female sex, ethnic group, social deprivation and diabetes mellitus were associated with an increased risk of CKD. 11 351 patients had a diagnosis of diabetes mellitus and were almost universally tested (99.3%) for CKD. The presence of albuminuria was strongly correlated with ethnic group, male sex and living in a deprived area. The retrospective electronic health record study with associated selection and testing bias are potential limitations of the present study. CONCLUSION: Chronic kidney disease prevalence in this region appears to be similar to other reported populations. The majority of those at risk for CKD were tested for reduced eGFR. The presence of albuminuria, an integral component of CKD diagnostic criteria, was under utilized in the non-diabetic population.


Asunto(s)
Albuminuria , Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas , Fallo Renal Crónico , Insuficiencia Renal Crónica , Adulto , Anciano , Albuminuria/diagnóstico , Albuminuria/epidemiología , Albuminuria/etiología , Creatinina/sangre , Nefropatías Diabéticas/diagnóstico , Nefropatías Diabéticas/epidemiología , Nefropatías Diabéticas/etiología , Progresión de la Enfermedad , Femenino , Tasa de Filtración Glomerular , Humanos , Fallo Renal Crónico/diagnóstico , Fallo Renal Crónico/epidemiología , Masculino , Persona de Mediana Edad , Nueva Zelanda/epidemiología , Prevalencia , Atención Primaria de Salud/métodos , Atención Primaria de Salud/estadística & datos numéricos , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/epidemiología , Insuficiencia Renal Crónica/fisiopatología , Estudios Retrospectivos , Factores de Riesgo
16.
J Genet Couns ; 26(1): 32-39, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27277130

RESUMEN

The introduction of cell-free DNA prenatal genetic screening has rekindled discussion of ethical and social questions surrounding prenatal testing, perceptions of disability, and abortion. The growing use of prenatal genetic screening presents a unique opportunity to assess decision-making around new methods of prenatal testing; especially as there is little available research comparing individual and cultural differences that affect a pregnant woman's decision-making on prenatal testing. We performed a content analysis of online pregnancy forums in the United States and Mainland China. Content from January 2012 to December 2013 was identified through search methodologies and refined to remove duplication. China-based content was translated by a native Mandarin speaker. We used qualitative analysis methods to identify common themes in the dataset. There were 333 English responses and 519 Mandarin responses. Three main themese were identified in the data: decision making factors, attitude towards the pregnancy, and attitudes towards abortion. Women's narratives reflected how broader social forces can have an impact on intimate personal decision-making. Women in the Mandarin dataset evoked stronger narratives of community and/or family decision-making in pregnancy and were more accepting of the possibility of abortion in the event of a finding of fetal abnormality. Narrative in the English dataset more frequently evoked ideas of unconditional love, regardless of fetal diagnosis, but also acknowledged much stronger support services for individuals with disability and less awareness of stigma. These results highlight the necessity of awareness around how broader cultural and social factors can consciously or unconsciously impact women's decisions and highlight potential focus areas for future counseling efforts.


Asunto(s)
Aborto Inducido , Toma de Decisiones , Pruebas Genéticas/ética , Padres/psicología , Diagnóstico Prenatal/psicología , Adulto , China , Femenino , Asesoramiento Genético , Humanos , Masculino , Narración , Embarazo , Diagnóstico Prenatal/ética , Estados Unidos , Adulto Joven
17.
Proc Natl Acad Sci U S A ; 111(30): 11013-8, 2014 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-24994902

RESUMEN

Poly-ß-1,6-N-acetyl-D-glucosamine (PNAG) is an exopolysaccharide produced by a wide variety of medically important bacteria. Polyglucosamine subunit B (PgaB) is responsible for the de-N-acetylation of PNAG, a process required for polymer export and biofilm formation. PgaB is located in the periplasm and likely bridges the inner membrane synthesis and outer membrane export machinery. Here, we present structural, functional, and molecular simulation data that suggest PgaB associates with PNAG continuously during periplasmic transport. We show that the association of PgaB's N- and C-terminal domains forms a cleft required for the binding and de-N-acetylation of PNAG. Molecular dynamics (MD) simulations of PgaB show a binding preference for N-acetylglucosamine (GlcNAc) to the N-terminal domain and glucosammonium to the C-terminal domain. Continuous ligand binding density is observed that extends around PgaB from the N-terminal domain active site to an electronegative groove on the C-terminal domain that would allow for a processive mechanism. PgaB's C-terminal domain (PgaB310-672) directly binds PNAG oligomers with dissociation constants of ∼1-3 mM, and the structures of PgaB310-672 in complex with ß-1,6-(GlcNAc)6, GlcNAc, and glucosamine reveal a unique binding mode suitable for interaction with de-N-acetylated PNAG (dPNAG). Furthermore, PgaB310-672 contains a ß-hairpin loop (ßHL) important for binding PNAG that was disordered in previous PgaB42-655 structures and is highly dynamic in the MD simulations. We propose that conformational changes in PgaB310-672 mediated by the ßHL on binding of PNAG/dPNAG play an important role in the targeting of the polymer for export and its release.


Asunto(s)
Amidohidrolasas/química , Biopelículas , Proteínas de Escherichia coli/química , Escherichia coli/fisiología , Periplasma/química , Polisacáridos Bacterianos/química , beta-Glucanos/química , Amidohidrolasas/genética , Amidohidrolasas/metabolismo , Transporte Biológico Activo/fisiología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Simulación del Acoplamiento Molecular , Periplasma/genética , Periplasma/metabolismo , Polisacáridos Bacterianos/genética , Polisacáridos Bacterianos/metabolismo , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , beta-Glucanos/metabolismo
19.
EMBO J ; 30(12): 2477-89, 2011 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-21556048

RESUMEN

The MEF2 factors regulate transcription during cardiac and skeletal myogenesis. MEF2 factors establish skeletal muscle commitment by amplifying and synergizing with MyoD. While phosphorylation is known to regulate MEF2 function, lineage-specific regulation is unknown. Here, we show that phosphorylation of MEF2C on T(80) by skeletal myosin light chain kinase (skMLCK) enhances skeletal and not cardiac myogenesis. A phosphorylation-deficient MEF2C mutant (MEFT80A) enhanced cardiac, but not skeletal myogenesis in P19 stem cells. Further, MEFT80A was deficient in recruitment of p300 to skeletal but not cardiac muscle promoters. In gain-of-function studies, skMLCK upregulated myogenic regulatory factor (MRF) expression, leading to enhanced skeletal myogenesis in P19 cells and more efficient myogenic conversion. In loss-of-function studies, MLCK was essential for efficient MRF expression and subsequent myogenesis in embryonic stem (ES) and P19 cells as well as for proper activation of quiescent satellite cells. Thus, skMLCK regulates MRF expression by controlling the MEF2C-dependent recruitment of histone acetyltransferases to skeletal muscle promoters. This work identifies the first kinase that regulates MyoD and Myf5 expression in ES or satellite cells.


Asunto(s)
Proteínas de Dominio MADS/metabolismo , Desarrollo de Músculos/fisiología , Músculo Esquelético/citología , Músculo Esquelético/enzimología , Factores Reguladores Miogénicos/metabolismo , Quinasa de Cadena Ligera de Miosina/fisiología , Secuencia de Aminoácidos , Animales , Carcinoma Embrionario/enzimología , Carcinoma Embrionario/patología , Línea Celular Tumoral , Células HEK293 , Humanos , Proteínas de Dominio MADS/fisiología , Factores de Transcripción MEF2 , Ratones , Datos de Secuencia Molecular , Factores Reguladores Miogénicos/fisiología , Células Madre Neoplásicas/enzimología , Células Madre Neoplásicas/patología , Especificidad de Órganos , Fosforilación , Treonina/metabolismo
20.
J Biol Chem ; 288(6): 4389-404, 2013 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-23266826

RESUMEN

The inhibition of MyoD expression is important for obtaining muscle progenitors that can replenish the satellite cell niche during muscle repair. Progenitors could be derived from either embryonic stem cells or satellite cells. Hedgehog (Hh) signaling is important for MyoD expression during embryogenesis and adult muscle regeneration. To date, the mechanistic understanding of MyoD regulation by Hh signaling is unclear. Here, we demonstrate that the Hh effector, Gli2, regulates MyoD expression and associates with MyoD gene elements. Gain- and loss-of-function experiments in pluripotent P19 cells show that Gli2 activity is sufficient and required for efficient MyoD expression during skeletal myogenesis. Inhibition of Hh signaling reduces MyoD expression during satellite cell activation in vitro. In addition to regulating MyoD expression, Hh signaling regulates MyoD transcriptional activity, and MyoD activates Hh signaling in myogenic conversion assays. Finally, Gli2, MyoD, and MEF2C form a protein complex, which enhances MyoD activity on skeletal muscle-related promoters. We therefore link Hh signaling to the function and expression of MyoD protein during myogenesis in stem cells.


Asunto(s)
Regulación de la Expresión Génica/fisiología , Proteínas Hedgehog/metabolismo , Proteína MioD/biosíntesis , Células Madre Pluripotentes/metabolismo , Células Satélite del Músculo Esquelético/metabolismo , Transducción de Señal/fisiología , Animales , Línea Celular , Proteínas Hedgehog/genética , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Factores de Transcripción MEF2 , Ratones , Ratones Transgénicos , Complejos Multiproteicos/genética , Complejos Multiproteicos/metabolismo , Desarrollo de Músculos/fisiología , Factores Reguladores Miogénicos/genética , Factores Reguladores Miogénicos/metabolismo , Células Madre Pluripotentes/citología , Células Satélite del Músculo Esquelético/citología , Proteína Gli2 con Dedos de Zinc
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