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Interactions govern the flow of information and the formation of correlations between constituents of many-body quantum systems, dictating phases of matter found in nature and forms of entanglement generated in the laboratory. Typical interactions decay with distance and thus produce a network of connectivity governed by geometry-such as the crystalline structure of a material or the trapping sites of atoms in a quantum simulator1,2. However, many envisioned applications in quantum simulation and computation require more complex coupling graphs including non-local interactions, which feature in models of information scrambling in black holes3-6 and mappings of hard optimization problems onto frustrated classical magnets7-11. Here we describe the realization of programmable non-local interactions in an array of atomic ensembles within an optical cavity, in which photons carry information between atomic spins12-19. By programming the distance dependence of the interactions, we access effective geometries for which the dimensionality, topology and metric are entirely distinct from the physical geometry of the array. As examples, we engineer an antiferromagnetic triangular ladder, a Möbius strip with sign-changing interactions and a treelike geometry inspired by concepts of quantum gravity5,20-22. The tree graph constitutes a toy model of holographic duality21,22, in which the quantum system lies on the boundary of a higher-dimensional geometry that emerges from measured correlations23. Our work provides broader prospects for simulating frustrated magnets and topological phases24, investigating quantum optimization paradigms10,11,25,26 and engineering entangled resource states for sensing and computation27,28.
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Using an ensemble of atoms in an optical cavity, we engineer a family of nonlocal Heisenberg Hamiltonians with continuously tunable anisotropy of the spin-spin couplings. We thus gain access to a rich phase diagram, including a paramagnetic-to-ferromagnetic Ising phase transition that manifests as a diverging magnetic susceptibility at the critical point. The susceptibility displays a symmetry between Ising interactions and XY (spin-exchange) interactions of the opposite sign, which is indicative of the spatially extended atomic system behaving as a single collective spin. Images of the magnetization dynamics show that spin-exchange interactions protect the coherence of the collective spin, even against inhomogeneous fields that completely dephase the noninteracting and Ising systems. Our results underscore prospects for harnessing spin-exchange interactions to enhance the robustness of spin squeezing protocols.
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We report direct observations of photon-mediated spin-exchange interactions in an atomic ensemble. Interactions extending over a distance of 500 µm are generated within a cloud of cold rubidium atoms coupled to a single mode of light in an optical resonator. We characterize the system via quench dynamics and imaging of the local magnetization, verifying the coherence of the interactions and demonstrating optical control of their strength and sign. Furthermore, by initializing the spin-1 system in the m_{f}=0 Zeeman state, we observe correlated pair creation in the m_{f}=±1 states, a process analogous to spontaneous parametric down-conversion and to spin mixing in Bose-Einstein condensates. Our work opens new opportunities in quantum simulation with long-range interactions and in entanglement-enhanced metrology.
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We propose an experimentally realizable quantum spin model that exhibits fast scrambling, based on nonlocal interactions that couple sites whose separation is a power of 2. By controlling the relative strengths of deterministic, nonrandom couplings, we can continuously tune from the linear geometry of a nearest-neighbor spin chain to an ultrametric geometry in which the effective distance between spins is governed by their positions on a tree graph. The transition in geometry can be observed in quench dynamics, and is furthermore manifest in calculations of the entanglement entropy. Between the linear and treelike regimes, we find a peak in entanglement and exponentially fast spreading of quantum information across the system. Our proposed implementation, harnessing photon-mediated interactions among cold atoms in an optical cavity, offers a test case for experimentally observing the emergent geometry of a quantum many-body system.
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We propose a robust scheme for generating macroscopic superposition states of spin or motion with the aid of a single photon. Shaping the wave packet of the photon enables high-fidelity preparation of nonclassical states of matter even in the presence of photon loss. Success is heralded by photodetection, enabling the scheme to be implemented with a weak coherent field. We analyze applications to preparing Schrödinger cat states of a collective atomic spin or of a mechanical oscillator coupled to an optical resonator. The method generalizes to preparing arbitrary superpositions of coherent states, enabling full quantum control. We illustrate this versatility by showing how to prepare Dicke or Fock states, as well as superpositions in the Dicke or Fock basis.
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PURPOSE: Non-adherence/persistence to adjuvant endocrine therapy can negatively impact survival. Beliefs about medicines are known to affect adherence. This study aims to identify socio-demographic and clinical characteristics associated with medication beliefs among women taking aromatase inhibitors (AIs). METHODS: Women completed an online survey on beliefs about AI therapy [Beliefs about Medicines Questionnaire (BMQ)], beliefs about breast cancer [Assessment of Survivor Concerns scale (ASC)], and depression [Personal Health Questionnaire depression scale (PHQ-8)]. Socio-demographic and clinical characteristics were collected. Bivariate analyses and linear regression models were performed to investigate relationships between variables. RESULTS: A total of 224 women reported currently taking AI therapy and were included in the analysis. Significantly higher concern beliefs were found among women who had at least mild depression, experienced side effects from AIs, and previously stopped therapy with another AI. Significant correlations were found between concern and necessity beliefs and cancer and health worry. Women age 70 and older displayed less fear of cancer recurrence and health worry, and a trend towards lower necessity and concern beliefs. No differences were found for other variables. In the regression model, greater necessity beliefs were found with increases in the number of current prescription medications (B = 1.06, 95% CI 0.31-1.81, p = 0.006) and shorter duration of current AI therapy (B = -0.65, 95% CI -1.23 to -0.07, p = 0.029), whereas greater concern beliefs were associated with higher depression scores (B = 1.19, 95% CI 0.35-2.03, p = 0.006). CONCLUSIONS: Medication necessity and concern beliefs were associated with a definable subset of patients who may be at higher risk for non-persistence.
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Antineoplásicos Hormonais/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Idoso , Neoplasias da Mama/psicologia , Estudos Transversais , Medo , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Adesão à Medicação , Pessoa de Meia-Idade , Pós-MenopausaRESUMO
Males exhibit shorter life span and more cognitive deficits, in the absence of dementia, in aging human populations. In mammals, the X chromosome is enriched for neural genes and is a major source of biologic sex difference, in part, because males show decreased expression of select X factors (XY). While each sex (XX and XY) harbors one active X due to X chromosome inactivation in females, some genes, such as Kdm6a, transcriptionally escape silencing in females-resulting in lower transcript levels in males. Kdm6a is a known histone demethylase (H3K27me2/3) with multiple functional domains that is linked with synaptic plasticity and cognition. Whether elevating Kdm6a could benefit the aged male brain and whether this requires its demethylase function remains unknown. We used lentiviral-mediated overexpression of the X factor in the hippocampus of aging male mice and tested their cognition and behavior in the Morris water-maze. We found that acutely increasing Kdm6a-in a form without demethylase function-selectively improved learning and memory, in the aging XY brain, without altering total activity or anxiety-like measures. Further understanding the demethylase-independent downstream mechanisms of Kdm6a may lead to novel therapies for treating age-induced cognitive deficits in both sexes.
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Histona Desmetilases , Cromossomo X , Masculino , Humanos , Feminino , Animais , Camundongos , Idoso , Cromossomo X/metabolismo , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Encéfalo/metabolismo , Cognição , Envelhecimento/genética , MamíferosRESUMO
The loading of copper (Cu) into cytochrome c oxidase (COX) in mitochondria is essential for energy production in cells. Extensive studies have been performed to characterize mitochondrial cuproenzymes that contribute to the metallation of COX, such as Sco1, Sco2, and Cox17. However, limited information is available on the upstream mechanism of Cu transport and delivery to mitochondria, especially through Cu-impermeable membranes, in mammalian cells. The mitochondrial phosphate transporter SLC25A3, also known as PiC2, binds Cu+ and transports the ion through these membranes in eukaryotic cells, ultimately aiding in the metallation of COX. We used the well-established differentiation model of primary myoblasts derived from mouse satellite cells, wherein Cu availability is necessary for growth and maturation, and showed that PiC2 is a target of MTF1, and its expression is both induced during myogenesis and favored by Cu supplementation. PiC2 deletion using CRISPR/Cas9 showed that the transporter is required for proliferation and differentiation of primary myoblasts, as both processes are delayed upon PiC2 knock-out. The effects of PiC2 deletion were rescued by the addition of Cu to the growth medium, implying the deleterious effects of PiC2 knockout in myoblasts may be in part due to a failure to deliver sufficient Cu to the mitochondria, which can be compensated by other mitochondrial cuproproteins. Co-localization and co-immunoprecipitation of PiC2 and COX also suggest that PiC2 may participate upstream in the copper delivery chain into COX, as verified by in vitro Cu+-transfer experiments. These data indicate an important role for PiC2 in both the delivery of Cu to the mitochondria and COX, favoring the differentiation of primary myoblasts.
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Missense mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common cause of familial Parkinson's disease (PD); however, pathways regulating LRRK2 subcellular localization, function, and turnover are not fully defined. We performed quantitative mass spectrometry-based interactome studies to identify 48 novel LRRK2 interactors, including the microtubule-associated E3 ubiquitin ligase TRIM1 (tripartite motif family 1). TRIM1 recruits LRRK2 to the microtubule cytoskeleton for ubiquitination and proteasomal degradation by binding LRRK2911-919, a nine amino acid segment within a flexible interdomain region (LRRK2853-981), which we designate the "regulatory loop" (RL). Phosphorylation of LRRK2 Ser910/Ser935 within LRRK2 RL influences LRRK2's association with cytoplasmic 14-3-3 versus microtubule-bound TRIM1. Association with TRIM1 modulates LRRK2's interaction with Rab29 and prevents upregulation of LRRK2 kinase activity by Rab29 in an E3-ligase-dependent manner. Finally, TRIM1 rescues neurite outgrowth deficits caused by PD-driving mutant LRRK2 G2019S. Our data suggest that TRIM1 is a critical regulator of LRRK2, controlling its degradation, localization, binding partners, kinase activity, and cytotoxicity.
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Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Doença de Parkinson , Proteínas Serina-Treonina Quinases , Proteínas com Motivo Tripartido , Citoesqueleto , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Proteínas Associadas aos Microtúbulos , Microtúbulos , Mutação , Doença de Parkinson/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Fatores de Transcrição , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Proteínas rab de Ligação ao GTP/metabolismoRESUMO
Importance: The X chromosome represents 5% of the human genome in women and men, and its influence on cognitive aging and Alzheimer disease (AD) is largely unknown. Objective: To determine whether the X chromosome is associated with sex-specific cognitive change and tau pathology in aging and AD. Design, Setting, Participants: This study examined differential gene expression profiling of the X chromosome from an RNA sequencing data set of the dorsolateral prefrontal cortex obtained from autopsied, elderly individuals enrolled in the Religious Orders Study and Rush Memory and Aging Project joint cohorts. Samples were collected from the cohort study with enrollment from 1994 to 2017. Data were last analyzed in May 2021. Main Outcomes and Measures: The main analysis examined whether X chromosome gene expression measured by RNA sequencing of the dorsolateral prefrontal cortex was associated with cognitive change during aging and AD, independent of AD pathology and at the transcriptome-wide level in women and men. Whether X chromosome gene expression was associated with neurofibrillary tangle burden, a measure of tau pathology that influences cognition, in women and men was also explored. Results: Samples for RNA sequencing of the dorsolateral prefrontal cortex were obtained from 508 individuals (mean [SD] age at death, 88.4 [6.6] years; 315 [62.0%] were female; 197 [38.8%] had clinical diagnosis of AD at death; 293 [58.2%] had pathological diagnosis of AD at death) enrolled in the Religious Orders Study and Rush Memory and Aging Project joint cohorts and were followed up annually for a mean (SD) of 6.3 (3.9) years. X chromosome gene expression (29 genes), adjusted for age at death, education, and AD pathology, was significantly associated with cognitive change at the genome-wide level in women but not men. In the majority of identified X genes (19 genes), increased expression was associated with slower cognitive decline in women. In contrast with cognition, X chromosome gene expression (3 genes), adjusted for age at death and education, was associated with neuropathological tau burden at the genome-wide level in men but not women. Conclusions and Relevance: In this study, the X chromosome was associated with cognitive trajectories and neuropathological tau burden in aging and AD in a sex-specific manner. This is important because specific X chromosome factors could contribute risk or resilience to biological pathways of aging and AD in women, men, or both.
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Envelhecimento/fisiologia , Doença de Alzheimer , Cromossomos Humanos X , Córtex Pré-Frontal Dorsolateral , Caracteres Sexuais , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Cognição , Disfunção Cognitiva , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Emaranhados Neurofibrilares/patologia , TranscriptomaRESUMO
A major sex difference in Alzheimer's disease (AD) is that men with the disease die earlier than do women. In aging and preclinical AD, men also show more cognitive deficits. Here, we show that the X chromosome affects AD-related vulnerability in mice expressing the human amyloid precursor protein (hAPP), a model of AD. XY-hAPP mice genetically modified to develop testicles or ovaries showed worse mortality and deficits than did XX-hAPP mice with either gonad, indicating a sex chromosome effect. To dissect whether the absence of a second X chromosome or the presence of a Y chromosome conferred a disadvantage on male mice, we varied sex chromosome dosage. With or without a Y chromosome, hAPP mice with one X chromosome showed worse mortality and deficits than did those with two X chromosomes. Thus, adding a second X chromosome conferred resilience to XY males and XO females. In addition, the Y chromosome, its sex-determining region Y gene (Sry), or testicular development modified mortality in hAPP mice with one X chromosome such that XY males with testicles survived longer than did XY or XO females with ovaries. Furthermore, a second X chromosome conferred resilience potentially through the candidate gene Kdm6a, which does not undergo X-linked inactivation. In humans, genetic variation in KDM6A was linked to higher brain expression and associated with less cognitive decline in aging and preclinical AD, suggesting its relevance to human brain health. Our study suggests a potential role for sex chromosomes in modulating disease vulnerability related to AD.
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Doença de Alzheimer , Doença de Alzheimer/genética , Animais , Feminino , Masculino , Camundongos , Caracteres Sexuais , Testículo , Cromossomo X/genética , Cromossomo YRESUMO
Female longevity is observed in humans and much of the animal kingdom, but its causes remain elusive. Using a genetic manipulation that generates XX and XY mice, each with either ovaries or testes, we show that the female XX sex chromosome complement increases survival during aging in male and female mice. In combination with ovaries, it also extends lifespan. Understanding causes of sex-based differences in aging could lead to new pathways to counter age-induced decline in both sexes.
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Longevidade/fisiologia , Cromossomo X/genética , Animais , Feminino , Masculino , Camundongos , Ovário/metabolismo , Análise de SobrevidaRESUMO
Alzheimer's disease (AD) begins several decades before the onset of clinical symptoms, at a time when women may still undergo reproductive cycling. Whether ovarian functions alter substrates of AD pathogenesis is unknown. Here we show that ovarian cycle stages significantly modulate AD-related alterations in neural network patterns, cognitive impairments, and pathogenic protein production in the hAPP-J20 mouse model of AD. Female hAPP mice spent more time in estrogen-dominant cycle stages and these ovarian stages worsened AD-related network dysfunction and cognitive impairments. In contrast, progesterone-dominant stages and gonadectomy attenuated these AD-related deficits. Further studies revealed a direct role for estradiol in stimulating neural network excitability and susceptibility to seizures in hAPP mice and increasing amyloid beta levels. Understanding dynamic effects of the ovarian cycle on the female nervous system in disease, including AD, is of critical importance and may differ from effects on a healthy brain. The pattern of ovarian cycle effects on disease-related networks, cognition, and pathogenic protein expression may be relevant to young women at risk for AD.
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Doença de Alzheimer/complicações , Ondas Encefálicas/fisiologia , Encéfalo/patologia , Transtornos Cognitivos , Ciclo Menstrual/fisiologia , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Castração , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/patologia , Transtornos Cognitivos/fisiopatologia , Convulsivantes/toxicidade , Modelos Animais de Doenças , Estradiol/metabolismo , Comportamento Exploratório/fisiologia , Feminino , Humanos , Ciclo Menstrual/genética , Camundongos , Camundongos Transgênicos , Mutação/genética , Pentilenotetrazol/toxicidade , Progesterona/metabolismo , Convulsões/induzido quimicamente , Convulsões/fisiopatologiaRESUMO
PURPOSE: The shift from infusion to oral oncolytic therapy presents challenges to oncology practitioners. The purpose of this study was to describe how a statewide quality-improvement collaborative can enhance quality of care for patients receiving oral oncolytic therapy. METHODS: The Michigan Oncology Quality Consortium hosted a series of learning sessions focused on oral oncolytic quality improvement, providing multiple resources to oncology community practices. The first five participating practices reported which of the evidence-based Michigan Oncology Quality Consortium resources provided were implemented at their site. They also performed prepost self-assessments in October 2013 and April 2015 and another in December 2017 to assess sustainability. Concordance with the ASCO Quality Oncology Practice Initiative oral chemotherapy standards, including documentation (five measures), patient education (seven measures), and follow-up/monitoring (four measures), was compared. RESULTS: All practices showed improvement between 2013 and 2015 in documentation (32% to 88%; P = .03), patient education (37% to 100%; P could not be calculated), and monitoring (40% to 80%; P > .2). Overall, a significant improvement in concordance was observed (36% to 91%; P = .03). Use of resources from each practice varied, and practices that used more resources showed greater improvements. There was a slight decrease in overall concordance between 2015 and 2017, which was not found to be significant (91% to 84%; P = .53). CONCLUSION: Use of tools from a quality-improvement collaborative improved concordance with national standards of care. Large-scale deployment of this model program may provide a clinically efficient and effective mechanism to enhance widespread change.
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Antineoplásicos , Oncologia , Neoplasias/epidemiologia , Padrões de Prática Médica , Administração Oral , Antineoplásicos/administração & dosagem , Documentação , Humanos , Oncologia/métodos , Oncologia/normas , Michigan , Neoplasias/tratamento farmacológico , Educação de Pacientes como Assunto , Padrões de Prática Médica/normas , Melhoria de Qualidade , Qualidade da Assistência à SaúdeRESUMO
Sleep deprivation is a public health epidemic that causes wide-ranging deleterious consequences, including impaired memory and cognition. Protein synthesis in hippocampal neurons promotes memory and cognition. The kinase complex mammalian target of rapamycin complex 1 (mTORC1) stimulates protein synthesis by phosphorylating and inhibiting the eukaryotic translation initiation factor 4E-binding protein 2 (4EBP2). We investigated the involvement of the mTORC1-4EBP2 axis in the molecular mechanisms mediating the cognitive deficits caused by sleep deprivation in mice. Using an in vivo protein translation assay, we found that loss of sleep impaired protein synthesis in the hippocampus. Five hours of sleep loss attenuated both mTORC1-mediated phosphorylation of 4EBP2 and the interaction between eukaryotic initiation factor 4E (eIF4E) and eIF4G in the hippocampi of sleep-deprived mice. Increasing the abundance of 4EBP2 in hippocampal excitatory neurons before sleep deprivation increased the abundance of phosphorylated 4EBP2, restored the amount of eIF4E-eIF4G interaction and hippocampal protein synthesis to that seen in mice that were not sleep-deprived, and prevented the hippocampus-dependent memory deficits associated with sleep loss. These findings collectively demonstrate that 4EBP2-regulated protein synthesis is a critical mediator of the memory deficits caused by sleep deprivation.
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Fatores de Iniciação em Eucariotos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Transtornos da Memória/metabolismo , Biossíntese de Proteínas , Privação do Sono/metabolismo , Animais , Western Blotting , Cognição , Proteínas do Citoesqueleto/metabolismo , Chaperona BiP do Retículo Endoplasmático , Ensaio de Imunoadsorção Enzimática , Fator de Iniciação 4E em Eucariotos/metabolismo , Fator de Iniciação Eucariótico 4G/metabolismo , Proteínas de Choque Térmico/metabolismo , Hipocampo/metabolismo , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Fosforilação , Puromicina/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Estatísticas não ParamétricasRESUMO
Ubiquitin-binding domains (UBDs) are crucial for recruiting many proteins to sites of DNA damage. Here we characterize C1orf124 (Spartan; referred to as DVC1), which has an UBZ4-type UBD found predominantly in DNA repair proteins. DVC1 associates with DNA replication factories and localizes to sites of DNA damage in human cells, in a manner that requires the ability of the DVC1 UBZ domain to bind to ubiquitin polymers in vitro and a conserved PCNA-interacting motif. DVC1 interacts with the p97 protein 'segregase'. We show that DVC1 recruits p97 to sites of DNA damage, where we propose that p97 facilitates the extraction of the translesion synthesis (TLS) polymerase (Pol) η during DNA repair to prevent excessive TLS and limit the incidence of mutations induced by DNA damage. We introduce DVC1 as a regulator of cellular responses to DNA damage that prevents mutations when DNA damage occurs.