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1.
J Exp Bot ; 75(9): 2733-2739, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38349794

RESUMO

A role for l-ascorbate as the precursor of several plant compounds adds to its already broad metabolic utility. There are many examples of plant species in which oxalate and l-threonate are formed from l-ascorbate breakdown, and a number of roles have been proposed for this: structural, physiological, and biochemical. On the other hand, the synthesis of l-tartrate from l-ascorbate remains limited to a very few species, amongst which we must be grateful to count the domesticated grapevine Vitis vinifera and its relatives on which wine production is based. Pathways for the degradation of ascorbate were first proposed ~50 years ago and have formed the basis of more recent biochemical and molecular analyses. The present review seeks to summarize some of these findings and to propose opportunities for future research.


Assuntos
Ácido Ascórbico , Ácido Ascórbico/metabolismo , Plantas/metabolismo , Redes e Vias Metabólicas , Vitis/metabolismo
2.
Clin Infect Dis ; 78(4): 833-841, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37823484

RESUMO

BACKGROUND: The gastrointestinal microbiota is an important line of defense against colonization with antimicrobial resistant (AR) bacteria. In this post hoc analysis of the phase 3 ECOSPOR III trial, we assessed impact of a microbiota-based oral therapeutic (fecal microbiota spores, live; VOWST Oral Spores [VOS], formerly SER-109]; Seres Therapeutics) compared with placebo, on AR gene (ARG) abundance in patients with recurrent Clostridioides difficile infection (rCDI). METHODS: Adults with rCDI were randomized to receive VOS or placebo orally for 3 days following standard-of-care antibiotics. ARG and taxonomic profiles were generated using whole metagenomic sequencing of stool at baseline and weeks 1, 2, 8, and 24 posttreatment. RESULTS: Baseline (n = 151) and serial posttreatment stool samples collected through 24 weeks (total N = 472) from 182 patients (59.9% female; mean age: 65.5 years) in ECOSPOR III as well as 68 stool samples obtained at a single time point from a healthy cohort were analyzed. Baseline ARG abundance was similar between arms and significantly elevated versus the healthy cohort. By week 1, there was a greater decline in ARG abundance in VOS versus placebo (P = .003) in association with marked decline of Proteobacteria and repletion of spore-forming Firmicutes, as compared with baseline. We observed abundance of Proteobacteria and non-spore-forming Firmicutes were associated with ARG abundance, while spore-forming Firmicutes abundance was negatively associated. CONCLUSIONS: This proof-of-concept analysis suggests that microbiome remodeling with Firmicutes spores may be a potential novel approach to reduce ARG colonization in the gastrointestinal tract.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Microbiota , Adulto , Humanos , Feminino , Idoso , Masculino , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Transplante de Microbiota Fecal , Clostridioides difficile/genética , Farmacorresistência Bacteriana , Infecções por Clostridium/microbiologia , Bactérias , Firmicutes
3.
Exp Neurol ; 370: 114562, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37802381

RESUMO

Parkinson's disease is a neurological disorder characterized by degeneration of midbrain dopamine neurons, which results in numerous adaptations in basal ganglia circuits. Research over the past twenty-five years has identified that midbrain dopamine neurons of the substantia nigra pars compacta (SNc) and ventral tegmental area (VTA) co-release multiple other transmitters including glutamate and GABA, in addition to their canonical transmitter, dopamine. This review summarizes previous work characterizing neurotransmitter co-release from dopamine neurons, work examining potential changes in co-release dynamics that result in animal models of Parkinson's disease, and future opportunities for determining how dysfunction in co-release may contribute to circuit dysfunction in Parkinson's disease.


Assuntos
Doença de Parkinson , Animais , Substância Negra , Área Tegmentar Ventral , Transmissão Sináptica , Neurônios Dopaminérgicos , Neurotransmissores
4.
Proc Natl Acad Sci U S A ; 120(42): e2309843120, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37812725

RESUMO

The burst firing of midbrain dopamine neurons releases a phasic dopamine signal that mediates reinforcement learning. At many synapses, however, high firing rates deplete synaptic vesicles (SVs), resulting in synaptic depression that limits release. What accounts for the increased release of dopamine by stimulation at high frequency? We find that adaptor protein-3 (AP-3) and its coat protein VPS41 promote axonal dopamine release by targeting vesicular monoamine transporter VMAT2 to the axon rather than dendrites. AP-3 and VPS41 also produce SVs that respond preferentially to high-frequency stimulation, independent of their role in axonal polarity. In addition, conditional inactivation of VPS41 in dopamine neurons impairs reinforcement learning, and this involves a defect in the frequency dependence of release rather than the amount of dopamine released. Thus, AP-3 and VPS41 promote the axonal polarity of dopamine release but enable learning by producing a distinct population of SVs tuned specifically to high firing frequency that confers the phasic release of dopamine.


Assuntos
Dopamina , Vesículas Sinápticas , Dopamina/metabolismo , Vesículas Sinápticas/metabolismo , Proteínas Vesiculares de Transporte de Monoamina/genética , Proteínas Vesiculares de Transporte de Monoamina/metabolismo , Axônios/metabolismo , Mesencéfalo/metabolismo
5.
J Alzheimers Dis ; 95(4): 1417-1425, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37694364

RESUMO

BACKGROUND: We have limited evidence for the relationship of high sugar intake with dementia risk. OBJECTIVE: To determine whether high sugar intake is associated with an increased risk of dementia in community-dwelling older adultsMethods:This study included 789 participants of the Rush Memory and Aging Project (community-based longitudinal cohort study of older adults free of known dementia at enrollment), with annual clinical assessments and complete nutrient data (obtained by validated food frequency questionnaire). Clinical diagnosis of dementia is based on the criteria of the joint working group of the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association. We used Cox proportional hazard models. RESULTS: 118 participants developed dementia during 7.3±3.8 years of follow-up. Those in the highest quintile of total sugar intake were twice as likely to develop dementia than those in the lowest quintile (Q5 versus Q1:HR=2.10 (95% CI: 1.05, 4.19) when adjusted for age, sex, education, APOEɛ4 allele, calories from sources other than sugar, physical activity, and diet score. Higher percent calories from sugar were positively associated with dementia risk (ß=0.042, p = 0.0009). In exploratory analyses, the highest versus lowest quintile of fructose and sucrose in the diet had higher dementia risk by 2.8 (95% CI: 1.38, 5.67) and 1.93 (95% CI: 1.05, 3.54) times, respectively. CONCLUSIONS: A higher intake of total sugar or total calories from sugar is associated with increased dementia risk in older adults. Among simple sugars, fructose (e.g., sweetened beverages, snacks, packaged desserts) and sucrose (table sugar in juices, desserts, candies, and commercial cereals) are associated with higher dementia risk.


Assuntos
Doença de Alzheimer , Vida Independente , Humanos , Idoso , Estudos Longitudinais , Sacarose Alimentar , Açúcares , Frutose
6.
bioRxiv ; 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37609166

RESUMO

The burst firing of midbrain dopamine neurons releases a phasic dopamine signal that mediates reinforcement learning. At many synapses, however, high firing rates deplete synaptic vesicles (SVs), resulting in synaptic depression that limits release. What accounts for the increased release of dopamine by stimulation at high frequency? We find that adaptor protein-3 (AP-3) and its coat protein VPS41 promote axonal dopamine release by targeting vesicular monoamine transporter VMAT2 to the axon rather than dendrites. AP-3 and VPS41 also produce SVs that respond preferentially to high frequency stimulation, independent of their role in axonal polarity. In addition, conditional inactivation of VPS41 in dopamine neurons impairs reinforcement learning, and this involves a defect in the frequency dependence of release rather than the amount of dopamine released. Thus, AP-3 and VPS41 promote the axonal polarity of dopamine release but enable learning by producing a novel population of SVs tuned specifically to high firing frequency that confers the phasic release of dopamine.

7.
Telemed J E Health ; 29(9): 1275-1288, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36787486

RESUMO

Introduction: With the coronavirus disease 2019 (COVID-19) pandemic, use of telehealth technology increased dramatically. Nonpharmacological approaches to pain management may be well suited for virtual care. Yet, it is not widely understood if this treatment modality is effective when delivered via videoconferencing. This review examines the effectiveness of movement-based and psychologically informed chronic pain management interventions delivered via videoconferencing compared to in-person care. Methods: Searches of MEDLINE® (via Ovid®), Embase (via Elsevier), CINAHL Complete (via EBSCO), and Cochrane Central Register of Controlled Trials (via Ovid) were performed from inception to June 10, 2021. All articles meeting eligibility criteria were included for data abstraction. Results: Eight thousand two hundred fifty-two citations were identified, and after removing duplicates, 4,661 citations remained. One study investigating acceptance and commitment therapy met eligibility criteria. The noninferiority randomized trial found no statistically significant difference in outcomes between delivery modalities. A horizon scan was conducted to assess planned or recent studies. Horizon scan results yielded six protocols in trial databases, one pilot study, and three published protocols for ongoing studies. Discussion: Findings from this study indicate that virtually delivered pain management is a possible substitute for in-person care. Given the paucity of evidence on this topic, further comparative and adequately powered studies that assess the impact of movement-based and psychologically informed pain management delivered via videoconferencing are needed. Conclusions: Research is needed to understand patient preferences of such interventions within a variety of settings. Such evaluations will be needed to guide clinical and operations practice to optimize equitable deployment and access to high-quality health care delivered via videoconferencing.


Assuntos
Terapia de Aceitação e Compromisso , COVID-19 , Dor Crônica , Humanos , Dor Crônica/terapia , Projetos Piloto , Comunicação por Videoconferência
8.
Mol Pharmacol ; 103(3): 188-198, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36456191

RESUMO

A dopamine D2 receptor mutation was recently identified in a family with a novel hyperkinetic movement disorder. That allelic variant D2-I212F is a constitutively active and G protein-biased receptor. We now describe mice engineered using CRISPR-Cas9-mediated gene editing technology to carry the D2-I212F variant. Drd2I212F mice exhibited gait abnormalities resembling those in other mouse models of chorea and/or dystonia and had striatal D2 receptor expression that was decreased approximately 30% per Drd2I212F allele. Electrically evoked inhibitory postsynaptic conductances in midbrain dopamine neurons and striatum from Drd2I212F mice, caused by G protein activation of potassium channels, exhibited slow kinetics (e.g., approximately four- to sixfold slower decay) compared with Drd2 +/+ mice. Current decay initiated by photolytic release of the D2 antagonist sulpiride from CyHQ-sulpiride was also ∼fourfold slower in midbrain slices from Drd2I212F mice than Drd2 +/+ mice. Furthermore, in contrast to Drd2 +/+ mice, in which dopamine is several-fold more potent at neurons in the nucleus accumbens than in the dorsal striatum, reflecting activation of Gα o versus Gα i, dopamine had similar potencies in those two brain regions of Drd2I212F mice. Repeated cocaine treatment, which decreases dopamine potency in the nucleus accumbens of Drd2 +/+ mice, had no effect on dopamine potency in Drd2 I212F mice. The results demonstrate the pathogenicity of the D2-I212F mutation and the utility of this mouse model for investigating the role of pathogenic DRD2 variants in early-onset hyperkinetic movement disorders. SIGNIFICANCE STATEMENT: The first dopamine receptor mutation to cause a movement disorder, D2-I212F, was recently identified. The mutation makes receptor activation of G protein-mediated signaling more efficient. To confirm the pathogenesis of D2-I212F, this study reports that mice carrying this mutation have gait abnormalities consistent with the clinical phenotype. The mutation also profoundly alters D2 receptor expression and function in vivo. This mouse model will be useful for further characterization of the mutant receptor and for evaluation of potential therapeutic drugs.


Assuntos
Dopamina , Transtornos dos Movimentos , Receptores de Dopamina D2 , Animais , Humanos , Camundongos , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Marcha/genética , Hipercinese , Mutação , Receptores de Dopamina D2/genética , Receptores de Dopamina D2/metabolismo , Sulpirida
9.
J Clin Psychol ; 79(4): 954-968, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36269895

RESUMO

OBJECTIVES: Moral reasoning is an underexamined and potentially useful area of research relative to the care of moral injury in veterans. However, the most widely used measure of moral reasoning, the moral foundations questionnaire (MFQ), has not been validated in this population. METHODS: Post-9/11 veterans (N = 311) completed questionnaires which included the MFQ. Veterans' scores were compared to the general US population. Confirmatory factor analysis was used to test existing models of the MFQ in the sample. Exploratory factor analysis (EFA) was also used to examine potentially improved model fits. RESULTS: The two leading, preexisting MFQ models were both poor fits for the data. EFA results produced a four-factor model for the veteran sample using 25 of the original 30 items of the MFQ. CONCLUSIONS: Measuring moral reasoning among veterans may be important in understanding the experience of moral injury. However, the most widely used scale (MFQ) performs poorly among a sample of post-9/11 veterans, indicating that veterans may respond differently to the measure than the general US population. Military culture may uniquely influence veterans' moral reasoning, suggesting the need for military specific measures for this construct.


Assuntos
Militares , Transtornos de Estresse Pós-Traumáticos , Veteranos , Humanos , Psicometria/métodos , Inquéritos e Questionários , Princípios Morais
10.
bioRxiv ; 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38168421

RESUMO

Activity-dependent protein synthesis is crucial for many long-lasting forms of synaptic plasticity. However, our understanding of the translational mechanisms controlling inhibitory synapses is limited. One distinct form of inhibitory long-term potentiation (iLTP) enhances postsynaptic clusters of GABAARs and the primary inhibitory scaffold, gephyrin, to promote sustained synaptic strengthening. While we previously found that persistent iLTP requires mRNA translation, the precise mechanisms controlling gephyrin translation during this process remain unknown. Here, we identify miR153 as a novel regulator of Gphn mRNA translation which controls gephyrin protein levels and synaptic clustering, ultimately impacting GABAergic synaptic structure and function. We find that iLTP induction downregulates miR153, reversing its translational suppression of Gphn mRNA and allowing for increased de novo gephyrin protein synthesis and synaptic clustering during iLTP. Finally, we find that reduced miR153 expression during iLTP is driven by an excitation-transcription coupling pathway involving calcineurin, NFAT and HDACs, which also controls the miRNA-dependent upregulation of GABAARs. Overall, this work delineates a miRNA-dependent post-transcriptional mechanism that controls the expression of the key synaptic scaffold, gephyrin, and may converge with parallel miRNA pathways to coordinate gene upregulation to maintain inhibitory synaptic plasticity.

11.
J Physiol ; 600(22): 4897-4916, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36156249

RESUMO

Excitatory inputs drive burst firing of locus coeruleus (LC) noradrenaline (NA) neurons in response to a variety of stimuli. Though a small number of glutamatergic LC afferents have been investigated, the overall landscape of these excitatory inputs is largely unknown. The current study used an optogenetic approach to isolate three glutamatergic afferents: the prefrontal cortex (PFC), lateral hypothalamus (LH) and periaqueductal grey (PAG). AAV5-DIO-ChR2 was injected into each region in male and female CaMKII-Cre mice and the properties of excitatory inputs on LC-NA cells were measured. Notably we found differences among these inputs. First, the pattern of axonal innervation differed between inputs such that LH afferents were concentrated in the posterior portion of the LC-NA somatic region while PFC afferents were denser in the medial dendritic region. Second, basal intrinsic properties varied for afferents, with LH inputs having the highest connectivity and the largest amplitude excitatory postsynaptic currents while PAG inputs had the lowest initial release probability. Third, while orexin and oxytocin had minimal effects on any input, dynorphin strongly inhibited excitatory inputs originating from the LH and PAG, and corticotrophin releasing factor (CRF) selectively inhibited inputs from the PAG. Overall, these results demonstrate that individual afferents to the LC have differing properties, which may contribute to the modularity of the LC and its ability to mediate various behavioural outcomes. KEY POINTS: Excitatory inputs to the locus coeruleus (LC) are important for driving noradrenaline neuron activity and downstream behaviours in response to salient stimuli, but little is known about the functional properties of different glutamate inputs that innervate these neurons We used a virus-mediated optogenetic approach to compare glutamate afferents from the prefrontal cortex (PFC), the lateral hypothalamus (LH) and the periaqueductal grey (PAG). While PFC was predicted to make synaptic inputs, we found that the LH and PAG also drove robust excitatory events in LC noradrenaline neurons. The strength, kinetics, and short-term plasticity of each input differed as did the extent of neuromodulation by both dynorphin and corticotrophin releasing factor. Thus each input displayed a unique set of basal properties and modulation by peptides. This characterization is an important step in deciphering the heterogeneity of the LC.


Assuntos
Dinorfinas , Locus Cerúleo , Masculino , Feminino , Camundongos , Animais , Locus Cerúleo/metabolismo , Dinorfinas/farmacologia , Ácido Glutâmico/farmacologia , Hormônio Liberador da Corticotropina/metabolismo , Norepinefrina/farmacologia , Hormônio Adrenocorticotrópico
12.
Antibiotics (Basel) ; 11(9)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36140013

RESUMO

Clostridioides difficile infection (CDI) is classified as an urgent health threat by the Centers for Disease Control and Prevention (CDC), and affects nearly 500,000 Americans annually. Approximately 20−25% of patients with a primary infection experience a recurrence, and the risk of recurrence increases with subsequent episodes to greater than 40%. The leading risk factor for CDI is broad-spectrum antibiotics, which leads to a loss of microbial diversity and impaired colonization resistance. Current FDA-approved CDI treatment strategies target toxin or toxin-producing bacteria, but do not address microbiome disruption, which is key to the pathogenesis of recurrent CDI. Fecal microbiota transplantation (FMT) reduces the risk of recurrent CDI through the restoration of microbial diversity. However, FDA safety alerts describing hospitalizations and deaths related to pathogen transmission have raised safety concerns with the use of unregulated and unstandardized donor-derived products. SER-109 is an investigational oral microbiome therapeutic composed of purified spore-forming Firmicutes. SER-109 was superior to a placebo in reducing CDI recurrence at Week 8 (12% vs. 40%, respectively; p < 0.001) in adults with a history of recurrent CDI with a favorable observed safety profile. Here, we discuss the role of the microbiome in CDI pathogenesis and the clinical development of SER-109, including its rigorous manufacturing process, which mitigates the risk of pathogen transmission. Additionally, we discuss compositional and functional changes in the gastrointestinal microbiome in patients with recurrent CDI following treatment with SER-109 that are critical to a sustained clinical response.

13.
Nanoscale Horiz ; 7(10): 1201-1209, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-35913108

RESUMO

Understanding and controlling the orbital alignment of molecules placed between electrodes is essential in the design of practically-applicable molecular and nanoscale electronic devices. The orbital alignment is highly determined by the molecule-electrode interface. Dependence of orbital alignment on the molecular anchor group for single molecular junctions has been intensively studied; however, when scaling-up single molecules to large parallel molecular arrays (like self-assembled monolayers (SAMs)), two challenges need to be addressed: 1. Most desired anchor groups do not form high quality SAMs. 2. It is much harder to tune the frontier molecular orbitals via a gate voltage in SAM junctions than in single molecular junctions. In this work, we studied the effect of the molecule-electrode interface in SAMs with a micro-pore device, using a recently developed tetrapodal anchor to overcome challenge 1, and the combination of a single layered graphene top electrode with an ionic liquid gate to solve challenge 2. The zero-bias orbital alignment of different molecules was signalled by a shift in conductance minimum vs. gate voltage for molecules with different anchoring groups. Molecules with the same backbone, but a different molecule-electrode interface, were shown experimentally to have conductances that differ by a factor of 5 near zero bias. Theoretical calculations using density functional theory support the trends observed in the experimental data. This work sheds light on how to control electron transport within the HOMO-LUMO energy gap in molecular junctions and will be applicable in scaling up molecular electronic systems for future device applications.

14.
Hortic Res ; 9: uhac118, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35928398

RESUMO

Several vineyard techniques have been proposed to delay grape maturity in light of the advanced maturation driven by increasingly frequent water and heat stress events that are detrimental to grape quality. These studies differ in terms of their experimental conditions, and in the present work we have attempted to summarize previous observations in a quantitative, data-driven systematic review. A meta-analysis of quantitative data gathered across 43 relevant studies revealed the overall significance of the proposed treatments and evaluated the impact of different experimental conditions on the outcome of antitranspirants, delayed pruning and late source limitation. Antitranspirants were most effective when applied twice and closer to veraison, while di-1-p-menthene increased the ripening delay by about 1 °Brix compared to kaolin. Larger ripening delays were achieved with delayed pruning of low-yielding vines or by pruning at later stages of apical bud development. Late defoliation or shoot trimming delayed ripening in high-yielding vines and represent suitable solutions for late-harvested varieties, but became ineffective where the treatment decreased yield. This quantitative meta-analysis of 242 primary observations uncovers factors affecting the efficacy of vineyard practices to delay ripening, which should be carefully considered by grape growers attempting to achieve this outcome.

15.
JACC Clin Electrophysiol ; 8(6): 782-791, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35738855

RESUMO

BACKGROUND: Smart watches and wearable technology capable of heart rhythm assessment have increased in use in the general population. The Apple Watch Series 4 (AW4) and KardiaBand (KB) are devices capable of obtaining single-lead electrocardiographic recordings, presenting a novel opportunity for the detection of paroxysmal arrhythmias. OBJECTIVES: The aim of this study was to assess the diagnostic utility of the AW4 and KB in an elderly outpatient population. METHODS: Consecutive recordings were taken from patients attending cardiology outpatient clinic from the AW4 and KB concurrently with 12-lead electrocardiography. Automated diagnoses and blinded single-lead electrocardiographic tracing interpretations by 2 cardiologists were analyzed. Analysis was also conducted to assess the effect of combined device and clinician interpretation. RESULTS: One hundred twenty-five patients were prospectively recruited (mean age 76 ± 7 years, 62% men). The accuracy of the automated rhythm assessment was higher with the KB than the AW4 (74% vs 65%). For the detection of atrial fibrillation, the sensitivity and negative predictive value of the KB were 89% and 97%, respectively, and of the AW4 were 19% and 82%, respectively. Using hybrid automated and clinician interpretation, the overall accuracy of the KB and AW4 was 91% and 87%, respectively. CONCLUSIONS: The KB automated algorithm outperformed the AW4 in its accuracy and sensitivity for detecting atrial fibrillation in the outpatient setting. Clinician assessment of the single-lead electrocardiogram improved accuracy. These findings suggest that although these devices' tracings are of sufficient quality, automated diagnosis alone is not sufficient for making clinical decisions about atrial fibrillation diagnosis and management.


Assuntos
Fibrilação Atrial , Dispositivos Eletrônicos Vestíveis , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Fibrilação Atrial/diagnóstico , Eletrocardiografia , Feminino , Humanos , Masculino , Valor Preditivo dos Testes
16.
Sci Adv ; 8(24): eabm2781, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35714181

RESUMO

An electron is usually considered to have only one form of kinetic energy, but could it have more, for its spin and charge, by exciting other electrons? In one dimension (1D), the physics of interacting electrons is captured well at low energies by the Tomonaga-Luttinger model, yet little has been observed experimentally beyond this linear regime. Here, we report on measurements of many-body modes in 1D gated wires using tunneling spectroscopy. We observe two parabolic dispersions, indicative of separate Fermi seas at high energies, associated with spin and charge excitations, together with the emergence of two additional 1D "replica" modes that strengthen with decreasing wire length. The interaction strength is varied by changing the amount of 1D intersubband screening by more than 45%. Our findings not only demonstrate the existence of spin-charge separation in the whole energy band outside the low-energy limit of the Tomonaga-Luttinger model but also set a constraint on the validity of the newer nonlinear Tomonaga-Luttinger theory.

17.
Cell Rep ; 39(7): 110823, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35584679

RESUMO

Substantia nigra pars compacta (SNc) dopamine neurons play a key role in regulating the activity of striatal circuits within the basal ganglia. In addition to dopamine, these neurons release several other transmitters, including the major inhibitory neurotransmitter γ-aminobutyric acid (GABA). Both dopamine and GABA are loaded into SNc synaptic vesicles by the vesicular monoamine transporter 2 (VMAT2), and co-release of GABA provides strong inhibition to the striatum by directly inhibiting striatal medium spiny projection neurons (MSNs) through activation of GABAA receptors. Here, we found that despite both dopamine and GABA being co-packaged by VMAT2, the properties of transmission, including Ca2+ sensitivity, release probability, and requirement of active zone scaffolding proteins, differ between the two transmitters. Moreover, the extent by which presynaptic neuromodulators inhibit co-transmission also varied. Differences in modulation and the mechanisms controlling release allow for independent regulation of dopamine and GABA signals despite both being loaded via similar mechanisms.


Assuntos
Corpo Estriado , Dopamina , Gânglios da Base/metabolismo , Corpo Estriado/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Substância Negra/metabolismo , Ácido gama-Aminobutírico/metabolismo
18.
BMJ ; 377: e068390, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35418416

RESUMO

OBJECTIVE: To determine the impact of lifestyle factors on life expectancy lived with and without Alzheimer's dementia. DESIGN: Prospective cohort study. SETTING: The Chicago Health and Aging Project, a population based cohort study in the United States. PARTICIPANTS: 2449 men and women aged 65 years and older. MAIN EXPOSURE: A healthy lifestyle score was developed based on five modifiable lifestyle factors: a diet for brain health (Mediterranean-DASH Diet Intervention for Neurodegenerative Delay-MIND diet score in upper 40% of cohort distribution), late life cognitive activities (composite score in upper 40%), moderate or vigorous physical activity (≥150 min/week), no smoking, and light to moderate alcohol consumption (women 1-15 g/day; men 1-30 g/day). MAIN OUTCOME: Life expectancy with and without Alzheimer's dementia in women and men. RESULTS: Women aged 65 with four or five healthy factors had a life expectancy of 24.2 years (95% confidence interval 22.8 to 25.5) and lived 3.1 years longer than women aged 65 with zero or one healthy factor (life expectancy 21.1 years, 19.5 to 22.4). Of the total life expectancy at age 65, women with four or five healthy factors spent 10.8% (2.6 years, 2.0 to 3.3) of their remaining years with Alzheimer's dementia, whereas women with zero or one healthy factor spent 19.3% (4.1 years, 3.2 to 5.1) with the disease. Life expectancy for women aged 65 without Alzheimer's dementia and four or five healthy factors was 21.5 years (20.0 to 22.7), and for those with zero or one healthy factor it was 17.0 years (15.5 to 18.3). Men aged 65 with four or five healthy factors had a total life expectancy of 23.1 years (21.4 to 25.6), which is 5.7 years longer than men aged 65 with zero or one healthy factor (life expectancy 17.4 years, 15.8 to 20.1). Of the total life expectancy at age 65, men with four or five healthy factors spent 6.1% (1.4 years, 0.3 to 2.0) of their remaining years with Alzheimer's dementia, and those with zero or one healthy factor spent 12.0% (2.1 years, 0.2 to 3.0) with the disease. Life expectancy for men aged 65 without Alzheimer's dementia and four or five healthy factors was 21.7 years (19.7 to 24.9), and for those with zero or one healthy factor life expectancy was 15.3 years (13.4 to 19.1). CONCLUSION: A healthy lifestyle was associated with a longer life expectancy among men and women, and they lived a larger proportion of their remaining years without Alzheimer's dementia. The life expectancy estimates might help health professionals, policy makers, and stakeholders to plan future healthcare services, costs, and needs.


Assuntos
Doença de Alzheimer , Idoso , Estudos de Coortes , Feminino , Estilo de Vida Saudável , Humanos , Expectativa de Vida , Estilo de Vida , Masculino , Estudos Prospectivos , Fatores de Risco , Estados Unidos/epidemiologia
20.
BMJ Case Rep ; 15(2)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35135791

RESUMO

A woman in her 80s was referred as an emergency case with a large oedematous and ulcerating lesion of the right breast. There was a 5-month history of increasing breast volume with new onset skin breakdown and discharge. Imaging revealed an extensive heterogeneous mass requiring drainage. No diagnosis was received from multiple biopsies and immediate surgical resection of the breast and axillary sampling was prioritised given the deteriorating patient condition. Postoperative histology identified a biphasic Adenomyoepithelioma of low malignant potential, a rare presentation compounding the complexity of management. The diagnostic uncertainty of this case highlighted the importance of MDT collaboration and the flexibility of current management pathways when dealing with cases requiring urgent surgical intervention. Axillary sampling in the context of unsuccessful preoperative biopsy represented a comprehensive means for assessing the need for further surgical or systemic management in the context of unconfirmed malignancy in a deteriorating patient.


Assuntos
Adenomioepitelioma , Neoplasias da Mama , Adenomioepitelioma/diagnóstico por imagem , Adenomioepitelioma/cirurgia , Biópsia , Mama/diagnóstico por imagem , Mama/cirurgia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/cirurgia , Feminino , Humanos , Incerteza
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