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1.
Hum Mol Genet ; 33(3): 245-253, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-37903062

RESUMO

Progranulin is an evolutionarily conserved protein that has been implicated in human neurodevelopmental and neurodegenerative diseases. Human progranulin is comprised of multiple cysteine-rich, biologically active granulin peptides. Granulin peptides accumulate with age and stress, however their functional contributions relative to full-length progranulin remain unclear. To address this, we generated C. elegans strains that produced quantifiable levels of both full-length progranulin/PGRN-1 protein and cleaved granulin peptide. Using these strains, we demonstrated that even in the presence of intact PGRN-1, granulin peptides suppressed the activity of the lysosomal aspartyl protease activity, ASP-3/CTSD. Granulin peptides were also dominant over PGRN-1 in compromising animal fitness as measured by progress through development and stress response. Finally, the degradation of human TDP-43 was impaired when the granulin to PGRN-1 ratio was increased, representing a disease-relevant downstream impact of impaired lysosomal function. In summary, these studies suggest that not only absolute progranulin levels, but also the balance between full-length progranulin and its cleavage products, is important in regulating lysosomal biology. Given its relevance in human disease, this suggests that the processing of progranulin into granulins should be considered as part of disease pathobiology and may represent a site of therapeutic intervention.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Granulinas , Progranulinas , Animais , Humanos , Caenorhabditis elegans/fisiologia , Granulinas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Doenças Neurodegenerativas , Progranulinas/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo
2.
Nat Methods ; 20(7): 1104-1113, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37429962

RESUMO

Genetically encoded voltage indicators (GEVIs) enable optical recording of electrical signals in the brain, providing subthreshold sensitivity and temporal resolution not possible with calcium indicators. However, one- and two-photon voltage imaging over prolonged periods with the same GEVI has not yet been demonstrated. Here, we report engineering of ASAP family GEVIs to enhance photostability by inversion of the fluorescence-voltage relationship. Two of the resulting GEVIs, ASAP4b and ASAP4e, respond to 100-mV depolarizations with ≥180% fluorescence increases, compared with the 50% fluorescence decrease of the parental ASAP3. With standard microscopy equipment, ASAP4e enables single-trial detection of spikes in mice over the course of minutes. Unlike GEVIs previously used for one-photon voltage recordings, ASAP4b and ASAP4e also perform well under two-photon illumination. By imaging voltage and calcium simultaneously, we show that ASAP4b and ASAP4e can identify place cells and detect voltage spikes with better temporal resolution than commonly used calcium indicators. Thus, ASAP4b and ASAP4e extend the capabilities of voltage imaging to standard one- and two-photon microscopes while improving the duration of voltage recordings.


Assuntos
Encéfalo , Cálcio , Animais , Camundongos , Iluminação , Microscopia , Fótons
3.
Proc Natl Acad Sci U S A ; 120(18): e2220160120, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37094165

RESUMO

War is the cause of tremendous human suffering. To reduce such harm, governments have developed tools to alert civilians of imminent threats. Whether these systems are effective remains largely unknown. We study the introduction of an innovative smartphone application that notifies civilians of impending military operations developed in coordination with the Ukrainian government after the Russian invasion. We leverage quasi-experimental variation in the timing of more than 3,000 alerts to study civilian sheltering behavior, using high-frequency geolocation pings tied to 17 million mobile devices, 60% of the connected population in Ukraine. We find that, overall, civilians respond sharply to alerts, quickly seeking shelter. These rapid postalert changes in population movement attenuate over time, however, in a manner that cannot be explained by adaptive sheltering behavior or calibration to the signal quality of alerts. Responsiveness is weakest when civilians have been living under an extended state of emergency, consistent with the presence of an alert fatigue effect. Our results suggest that 35 to 45% of observed civilian casualties were avoided because of public responsiveness to the messaging system. Importantly, an additional 8 to 15% of civilian casualties observed during the later periods of the conflict could have been avoided with sustained public responsiveness to government alerts. We provide evidence that increasing civilians' risk salience through targeted government messaging can increase responsiveness, suggesting a potential policy lever for sustaining public engagement during prolonged episodes of conflict.


Assuntos
Etnicidade , Guerra , Humanos , Ucrânia , Federação Russa
4.
Nat Chem Biol ; 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884806

RESUMO

Impaired redox metabolism is a key contributor to the etiology of many diseases, including primary mitochondrial disorders, cancer, neurodegeneration and aging. However, mechanistic studies of redox imbalance remain challenging due to limited strategies that can perturb redox metabolism in various cellular or organismal backgrounds. Most studies involving impaired redox metabolism have focused on oxidative stress; consequently, less is known about the settings where there is an overabundance of NADH reducing equivalents, termed reductive stress. Here we introduce a soluble transhydrogenase from Escherichia coli (EcSTH) as a novel genetically encoded tool to promote reductive stress in living cells. When expressed in mammalian cells, EcSTH, and a mitochondrially targeted version (mitoEcSTH), robustly elevated the NADH/NAD+ ratio in a compartment-specific manner. Using this tool, we determined that metabolic and transcriptomic signatures of the NADH reductive stress are cellular background specific. Collectively, our novel genetically encoded tool represents an orthogonal strategy to promote reductive stress.

5.
Nature ; 567(7747): 249-252, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30842658

RESUMO

The liver is the most common site of metastatic disease1. Although this metastatic tropism may reflect the mechanical trapping of circulating tumour cells, liver metastasis is also dependent, at least in part, on the formation of a 'pro-metastatic' niche that supports the spread of tumour cells to the liver2,3. The mechanisms that direct the formation of this niche are poorly understood. Here we show that hepatocytes coordinate myeloid cell accumulation and fibrosis within the liver and, in doing so, increase the susceptibility of the liver to metastatic seeding and outgrowth. During early pancreatic tumorigenesis in mice, hepatocytes show activation of signal transducer and activator of transcription 3 (STAT3) signalling and increased production of serum amyloid A1 and A2 (referred to collectively as SAA). Overexpression of SAA by hepatocytes also occurs in patients with pancreatic and colorectal cancers that have metastasized to the liver, and many patients with locally advanced and metastatic disease show increases in circulating SAA. Activation of STAT3 in hepatocytes and the subsequent production of SAA depend on the release of interleukin 6 (IL-6) into the circulation by non-malignant cells. Genetic ablation or blockade of components of IL-6-STAT3-SAA signalling prevents the establishment of a pro-metastatic niche and inhibits liver metastasis. Our data identify an intercellular network underpinned by hepatocytes that forms the basis of a pro-metastatic niche in the liver, and identify new therapeutic targets.


Assuntos
Hepatócitos/patologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Fígado/patologia , Metástase Neoplásica , Neoplasias Pancreáticas/patologia , Microambiente Tumoral , Animais , Carcinoma Ductal Pancreático/patologia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/secundário , Feminino , Interleucina-6/metabolismo , Masculino , Camundongos , Fator de Transcrição STAT3/metabolismo , Proteína Amiloide A Sérica/metabolismo
6.
J Am Chem Soc ; 146(6): 3742-3754, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38316637

RESUMO

Cobalt polypyridyl complexes stand out as efficient catalysts for electrochemical proton reduction, but investigations into their operating mechanisms, with broad-reaching implications in catalyst design, have been limited. Herein, we investigate the catalytic activity of a cobalt(II) polypyridyl complex bearing a pendant pyridyl base with a series of organic acids spanning 20 pKa units in acetonitrile. Structural analysis, as well as electrochemical studies, reveals that the Co(III) hydride intermediate is formed through reduction of the Co(II) catalyst followed by direct metal protonation in the initial EC step despite the presence of the pendant base, which is commonly thought of as a more kinetically accessible protonation site. Protonation of the pendant base occurs after the Co(III) hydride intermediate is further reduced in the overall ECEC pathway. Additionally, when the acid used is sufficiently strong, the Co(II) catalyst can be protonated, and the Co(III) hydride can react directly with acid to release H2. With thorough mechanistic understanding, the appropriate electroanalytical methods were identified to extract rate constants for the elementary steps over a range of conditions. Thermodynamic square schemes relating catalytic intermediates proposed in the three electrocatalytic HER mechanisms were constructed. These findings reveal a full description of the HER electrocatalysis mediated by this molecular system and provide insights into strategies to improve synthetic fuel-forming catalysts operative through metal hydride intermediates.

7.
Genome Res ; 31(12): 2327-2339, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34815311

RESUMO

Chromatin accessibility states that influence gene expression and other nuclear processes can be altered in disease. The constellation of transcription factors and chromatin regulatory complexes in cells results in characteristic patterns of chromatin accessibility. The study of these patterns in tissues has been limited because existing chromatin accessibility assays are ineffective for archival formalin-fixed, paraffin-embedded (FFPE) tissues. We have developed a method to efficiently extract intact chromatin from archival tissue via enhanced cavitation with a nanodroplet reagent consisting of a lipid shell with a liquid perfluorocarbon core. Inclusion of nanodroplets during the extraction of chromatin from FFPE tissues enhances the recovery of intact accessible and nucleosome-bound chromatin. We show that the addition of nanodroplets to the chromatin accessibility assay formaldehyde-assisted isolation of regulatory elements (FAIRE), does not affect the accessible chromatin signal. Applying the technique to FFPE human tumor xenografts, we identified tumor-relevant regions of accessible chromatin shared with those identified in primary tumors. Further, we deconvoluted non-tumor signal to identify cellular components of the tumor microenvironment. Incorporation of this method of enhanced cavitation into FAIRE offers the potential for extending chromatin accessibility to clinical diagnosis and personalized medicine, while also enabling the exploration of gene regulatory mechanisms in archival samples.

8.
Metab Eng ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38936762

RESUMO

Biological conversion of lignin from biomass offers a promising strategy for sustainable production of fuels and chemicals. However, aromatic compounds derived from lignin commonly contain methoxy groups, and O-demethylation of these substrates is often a rate-limiting reaction that influences catabolic efficiency. Several enzyme families catalyze aromatic O-demethylation, but they are rarely compared in vivo to determine an optimal biocatalytic strategy. Here, two pathways for aromatic O-demethylation were compared in Pseudomonas putida KT2440. The native Rieske non-heme iron monooxygenase (VanAB) and, separately, a heterologous tetrahydrofolate-dependent demethylase (LigM) were constitutively expressed in P. putida, and the strains were optimized via adaptive laboratory evolution (ALE) with vanillate as a model substrate. All evolved strains displayed improved growth phenotypes, with the evolved strains harboring the native VanAB pathway exhibiting growth rates ∼1.8x faster than those harboring the heterologous LigM pathway. Enzyme kinetics and transcriptomics studies investigated the contribution of selected mutations toward enhanced utilization of vanillate. The VanAB-overexpressing strains contained the most impactful mutations, including those in VanB, the reductase for vanillate O-demethylase, PP_3494, a global regulator of vanillate catabolism, and fghA, involved in formaldehyde detoxification. These three mutations were combined into a single strain, which exhibited approximately 5x faster vanillate consumption than the wild-type strain in the first 8 h of cultivation. Overall, this study illuminates the details of vanillate catabolism in the context of two distinct enzymatic mechanisms, yielding a platform strain for efficient O-demethylation of lignin-related aromatic compounds to value-added products.

9.
Pediatr Blood Cancer ; : e31169, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961583

RESUMO

Methotrexate is a critical component of curative chemotherapy for pediatric acute lymphoblastic leukemia (ALL), but is associated with neurotoxicity. Information on long-term outcomes following an acute neurotoxic event is limited. Therefore, this report compares neurocognitive performance more than 12 months post diagnosis (mean = 4 years) between ALL patients with (n = 25) and without (n = 146) a history of acute neurotoxicity. Compared to children with no documented on-treatment neurotoxic event, children who experienced a neurotoxic event during treatment exhibited poorer performance on measures of fine motor function (p = .02) and attention (p = .02). Children with ALL who experience acute neurotoxicity may be candidates for early neuropsychological screening and intervention.

10.
Endocr Pract ; 30(1): 11-18, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37805100

RESUMO

OBJECTIVE: To assess the effect of relacorilant, a selective glucocorticoid receptor modulator under investigation for the treatment of patients with endogenous hypercortisolism (Cushing syndrome [CS]), on the heart rate-corrected QT interval (QTc). METHODS: Three clinical studies of relacorilant were included: (1) a first-in-human, randomized, placebo-controlled, ascending-dose (up to 500 mg of relacorilant) study in healthy volunteers; (2) a phase 1 placebo- and positive-controlled thorough QTc (TQT) study of 400 and 800 mg of relacorilant in healthy volunteers; and (3) a phase 2, open-label study of up to 400 mg of relacorilant administered daily for up to 16 weeks in patients with CS. Electrocardiogram recordings were taken, and QTc change from baseline (ΔQTc) was calculated. The association of plasma relacorilant concentration with the effect on QTc in healthy volunteers was assessed using linear mixed-effects modeling. RESULTS: Across all studies, no notable changes in the electrocardiogram parameters were observed. At all time points and with all doses of relacorilant, including supratherapeutic doses, ΔQTc was small, generally negative, and, in the placebo-controlled studies, similar to placebo. In the TQT study, placebo-corrected ΔQTc with relacorilant was small and negative, whereas placebo-corrected ΔQTc with moxifloxacin positive control showed rapid QTc prolongation. These results constituted a negative TQT study. The model-estimated slopes of the concentration-QTc relationship were slightly negative, excluding an association of relacorilant with prolonged QTc. CONCLUSION: At all doses studied, relacorilant consistently demonstrated a lack of QTc prolongation in healthy volunteers and patients with CS, including in the TQT study. Ongoing phase 3 studies will help further establish the overall benefit-risk profile of relacorilant.


Assuntos
Síndrome de Cushing , Síndrome do QT Longo , Humanos , Estudos Cross-Over , Síndrome de Cushing/tratamento farmacológico , Relação Dose-Resposta a Droga , Método Duplo-Cego , Eletrocardiografia , Voluntários Saudáveis , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/tratamento farmacológico , Moxifloxacina , Receptores de Glucocorticoides , Ensaios Clínicos Controlados Aleatórios como Assunto , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto
11.
Artif Organs ; 48(6): 675-682, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38321771

RESUMO

INTRODUCTION: For the Veterans Health Administration (VHA) to continue to perform complex cardiothoracic surgery, there must be an established pathway for providing urgent/emergent extracorporeal life support (ECLS). Partnership with a nearby tertiary care center with such expertise may be the most resource-efficient way to provide ECLS services to patients in post-cardiotomy cardiogenic shock or respiratory failure. The goal of this project was to assess the efficiency, safety, and outcomes of surgical patients who required transfer for perioperative ECLS from a single stand-alone Veterans Affairs Medical Center (VAMC) to a separate ECLS center. METHODS: Cohort consisted of all cardiothoracic surgery patients who experienced cardiogenic shock or refractory respiratory failure at the local VAMC requiring urgent or emergent institution of ECLS between 2019 and 2022. The primary outcomes are the safety and timeliness of transport. RESULTS: Mean time from the initial shock call to arrival at the ECLS center was 2.8 h. There were no complications during transfer. Six patients (86%) survived to decannulation. CONCLUSION: These results suggest that complex cardiothoracic surgery can be performed within the VHA system and when there is an indication for ECLS, those services can be safely and effectively provided at an affiliated, properly equipped center.


Assuntos
Oxigenação por Membrana Extracorpórea , Hospitais de Veteranos , Choque Cardiogênico , United States Department of Veterans Affairs , Humanos , Oxigenação por Membrana Extracorpórea/métodos , Estados Unidos , Choque Cardiogênico/terapia , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Insuficiência Respiratória/terapia , Procedimentos Cirúrgicos Cardíacos/métodos , Estudos Retrospectivos , Transferência de Pacientes
12.
J Head Trauma Rehabil ; 39(3): 218-230, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38709830

RESUMO

OBJECTIVE: To describe associations between a history of traumatic brain injury (TBI) and the severity of tinnitus-related functional impairment among a national, stratified random sample of veterans diagnosed with tinnitus by the Department of Veterans Affairs (VA) healthcare system. SETTING: A multimodal (mailed and internet) survey administered in 2018. Participants: VA healthcare-using veterans diagnosed with tinnitus; veterans with comorbid TBI diagnosis were oversampled. DESIGN: A population-based survey. MAIN MEASURES: TBI history was assessed using International Classification of Diseases (ICD) diagnosis codes in veterans' VA electronic health records. The severity of participants' overall tinnitus-related functional impairment was measured using the Tinnitus Functional Index. Population prevalence and 95% confidence intervals (CIs) were estimated using inverse probability weights accounting for sample stratification and survey nonresponse. Veterans' relative risk ratios of very severe or moderate/severe tinnitus-related functional impairment, versus none/mild impairment, were estimated by TBI history using bivariable and multivariable multinomial logistic regression. RESULTS: The population prevalence of TBI was 5.6% (95% CI: 4.8-6.4) among veterans diagnosed with tinnitus. Veterans with a TBI diagnosis, compared with those without a TBI diagnosis, had 3.6 times greater likelihood of rating their tinnitus-related impairment as very severe (95% CI: 2.1-6.3), and 1.5 times greater likelihood of rating their impairment as moderate/severe (95% CI: 1.0-2.4), versus none/mild. CONCLUSIONS: These findings suggest an important role of TBI in the severity of tinnitus-related functional impairment among veterans. This knowledge can help inform the integration of tinnitus management services into the care received by veterans with TBI.


Assuntos
Lesões Encefálicas Traumáticas , Índice de Gravidade de Doença , Zumbido , Veteranos , Humanos , Zumbido/epidemiologia , Masculino , Feminino , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/epidemiologia , Estados Unidos , Pessoa de Meia-Idade , Adulto , Idoso , Prevalência
13.
Artigo em Inglês | MEDLINE | ID: mdl-38944415

RESUMO

Corynebacterium glutamicum ATCC 13032 is a promising microbial chassis for industrial production of valuable compounds, including aromatic amino acids derived from the shikimate pathway. In this work, we developed two whole-cell, transcription factor based fluorescent biosensors to track cis, cis-muconic acid (ccMA) and chorismate in C. glutamicum. Chorismate is a key intermediate in the shikimate pathway from which value-added chemicals can be produced, and a shunt from the shikimate pathway can divert carbon to ccMA, a high value chemical. We transferred a ccMA-inducible transcription factor, CatM, from Acinetobacter baylyi ADP1 into C. glutamicum and screened a promoter library to isolate variants with high sensitivity and dynamic range to ccMA by providing benzoate, which is converted to ccMA intracellularly. The biosensor also detected exogenously supplied ccMA, suggesting the presence of a putative ccMA transporter in C. glutamicum, though the external ccMA concentration threshold to elicit a response was 100-fold higher than the concentration of benzoate required to do so through intracellular ccMA production. We then developed a chorismate biosensor, in which a chorismate inducible promoter regulated by natively expressed QsuR was optimized to exhibit a dose-dependent response to exogenously supplemented quinate (a chorismate precursor). A chorismate-pyruvate lyase encoding gene, ubiC, was introduced into C. glutamicum to lower the intracellular chorismate pool, which resulted in loss of dose-dependence to quinate. Further, a knockout strain that blocked the conversion of quinate to chorismate, also resulted in absence of dose-dependence to quinate, validating that the chorismate biosensor is specific to intracellular chorismate pool. The ccMA and chorismate biosensors were dually inserted into C. glutamicum to simultaneously detect intracellularly produced chorismate and ccMA. Biosensors, such as those developed in this study, can be applied in C. glutamicum for multiplex sensing to expedite pathway design and optimization through metabolic engineering in this promising chassis organism.

14.
Proc Natl Acad Sci U S A ; 118(3)2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33431688

RESUMO

The C-terminal domain (CTD) kinase I (CTDK-1) complex is the primary RNA Polymerase II (Pol II) CTD Ser2 kinase in budding yeast. CTDK-1 consists of a cyclin-dependent kinase (CDK) Ctk1, a cyclin Ctk2, and a unique subunit Ctk3 required for CTDK-1 activity. Here, we present a crystal structure of CTDK-1 at 1.85-Å resolution. The structure reveals that, compared to the canonical two-component CDK-cyclin system, the third component Ctk3 of CTDK-1 plays a critical role in Ctk1 activation by stabilizing a key element of CDK regulation, the T-loop, in an active conformation. In addition, Ctk3 contributes to the assembly of CTDK-1 through extensive interactions with both Ctk1 and Ctk2. We also demonstrate that CTDK-1 physically and genetically interacts with the serine/arginine-like protein Gbp2. Together, the data in our work reveal a regulatory mechanism of CDK complexes.


Assuntos
Quinases Ciclina-Dependentes/ultraestrutura , Proteínas Quinases/ultraestrutura , RNA Polimerase II/ultraestrutura , Proteínas de Saccharomyces cerevisiae/ultraestrutura , Transcrição Gênica , Sequência de Aminoácidos/genética , Núcleo Celular/genética , Núcleo Celular/ultraestrutura , Cristalografia por Raios X , Quinases Ciclina-Dependentes/genética , Ciclinas/química , Ciclinas/ultraestrutura , Complexos Multiproteicos/genética , Complexos Multiproteicos/ultraestrutura , Fosforilação , Conformação Proteica , Proteínas Quinases/genética , RNA Polimerase II/genética , Proteínas de Ligação a RNA/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/ultraestrutura , Proteínas de Saccharomyces cerevisiae/genética
15.
Proc Natl Acad Sci U S A ; 118(24)2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34103399

RESUMO

Exposure to adversity can accelerate biological aging. However, existing biomarkers of early aging are either costly and difficult to collect, like epigenetic signatures, or cannot be detected until late childhood, like pubertal onset. We evaluated the hypothesis that early adversity is associated with earlier molar eruption, an easily assessed measure that has been used to track the length of childhood across primates. In a preregistered analysis (n = 117, ages 4 to 7 y), we demonstrate that lower family income and exposure to adverse childhood experiences (ACEs) are significantly associated with earlier eruption of the first permanent molars, as rated in T2-weighted magnetic resonance images (MRI). We replicate relationships between income and molar eruption in a population-representative dataset (National Health and Nutrition Examination Survey; n = 1,973). These findings suggest that the impact of stress on the pace of biological development is evident in early childhood, and detectable in the timing of molar eruption.


Assuntos
Experiências Adversas da Infância , Dente Molar/crescimento & desenvolvimento , Criança , Pré-Escolar , Feminino , Humanos , Renda , Imageamento por Ressonância Magnética , Masculino , Dente Molar/diagnóstico por imagem , Erupção Dentária
16.
J Neurosci ; 42(44): 8237-8251, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36192151

RESUMO

Human childhood is characterized by dramatic changes in the mind and brain. However, little is known about the large-scale intrinsic cortical network changes that occur during childhood because of methodological challenges in scanning young children. Here, we overcome this barrier by using sophisticated acquisition and analysis tools to investigate functional network development in children between the ages of 4 and 10 years ([Formula: see text]; 50 female, 42 male). At multiple spatial scales, age is positively associated with brain network segregation. At the system level, age was associated with segregation of systems involved in attention from those involved in abstract cognition, and with integration among attentional and perceptual systems. Associations between age and functional connectivity are most pronounced in visual and medial prefrontal cortex, the two ends of a gradient from perceptual, externally oriented cortex to abstract, internally oriented cortex. These findings suggest that both ends of the sensory-association gradient may develop early, in contrast to the classical theories that cortical maturation proceeds from back to front, with sensory areas developing first and association areas developing last. More mature patterns of brain network architecture, controlling for age, were associated with better visuospatial reasoning abilities. Our results suggest that as cortical architecture becomes more specialized, children become more able to reason about the world and their place in it.SIGNIFICANCE STATEMENT Anthropologists have called the transition from early to middle childhood the "age of reason", when children across cultures become more independent. We employ cutting-edge neuroimaging acquisition and analysis approaches to investigate associations between age and functional brain architecture in childhood. Age was positively associated with segregation between cortical systems that process the external world and those that process abstract phenomena like the past, future, and minds of others. Surprisingly, we observed pronounced development at both ends of the sensory-association gradient, challenging the theory that sensory areas develop first and association areas develop last. Our results open new directions for research into how brains reorganize to support rapid gains in cognitive and socioemotional skills as children reach the age of reason.


Assuntos
Mapeamento Encefálico , Cognição , Humanos , Criança , Masculino , Feminino , Pré-Escolar , Encéfalo/diagnóstico por imagem , Sensação , Resolução de Problemas , Imageamento por Ressonância Magnética
17.
J Am Chem Soc ; 145(2): 1367-1377, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36595559

RESUMO

Strong-field hexadentate ligands were synthesized and coordinated to cobalt metal centers to result in three new low-spin to low-spin Co(III/II) redox couples. The ligand backbone has been modified with dimethyl amine groups to result in redox potential tuning of the Co(III/II) redox couples from -200 to -430 mV versus Fc+/0. The redox couples surprisingly undergo a reversible molecular switch rearrangement from five-coordinate Co(II) to six-coordinate Co(III) despite the ligands being hexadentate. The complexes exhibit modestly faster electron self-exchange rate constants of 2.2-4.2 M-1 s-1 compared to the high-spin to low-spin redox couple [Co(bpy)3]3+/2+ at 0.27 M-1 s-1, which is attributed to the change in spin state being somewhat offset by this coordination switching behavior. The complexes were utilized as redox shuttles in dye-sensitized solar cells with the near-IR AP25 + D35 dye system and exhibited improved photocurrents over the [Co(bpy)3]3+/2+ redox shuttle (19.8 vs 18.0 mA/cm2). Future directions point toward pairing the low-spin to low-spin Co(II/III) tunable series to dyes with significantly more negative highest occupied molecular orbital potentials that absorb into the near-IR where outer sphere redox shuttles have failed to produce efficient dye regeneration.


Assuntos
Cobalto , Luz Solar , Ligantes , Oxirredução , Corantes
18.
Cancer ; 129(8): 1287-1294, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36692972

RESUMO

BACKGROUND: High-dose methotrexate (HD-MTX; 5000 mg/m2 ) is an important component of curative therapy in many treatment regimens for high-risk pediatric acute lymphoblastic leukemia (ALL). However, methotrexate therapy can result in dose-limiting neurotoxicity, which may disproportionately affect Latino children. This study evaluated risk factors for neurotoxicity after HD-MTX in an ethnically diverse population of patients with ALL. METHODS: The authors retrospectively reviewed the medical records of patients who were diagnosed with ALL and treated with HD-MTX at Texas Children's Cancer Center (2010-2017). Methotrexate neurotoxicity was defined as a neurologic episode (e.g., seizures or stroke-like symptoms) occurring within 21 days of HD-MTX that resulted in methotrexate treatment modifications. Mixed effects multivariable logistic regression was used to estimate the odds ratio (OR) and corresponding 95% confidence interval (CI) for the association between clinical factors and neurotoxicity. RESULTS: Overall, 351 patients (58.1% Latino) who received 1183 HD-MTX infusions were evaluated. Thirty-five patients (10%) experienced neurotoxicity, 71% of whom were Latino. After adjusting for clinical risk factors, the authors observed that serum creatinine elevations ≥50% of baseline were associated with a three-fold increased odds (OR, 3.32; 95% CI, 0.98-11.21; p = .05) for neurotoxicity compared with creatinine elevation <25%. Notably, predictors of neurotoxicity differed by ethnicity. Specifically, Latino children experienced a nearly six-fold increase in neurotoxicity odds (OR, 5.80; 95% CI, 1.39-24.17; p = .02) with serum creatinine elevation ≥50% compared with creatinine elevation <25%. CONCLUSIONS: The current findings indicate that serum creatinine elevations ≥50% may be associated with an increased risk for neurotoxicity among Latino children with ALL and may identify potential candidates for therapeutic or supportive care interventions.


Assuntos
Síndromes Neurotóxicas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Criança , Humanos , Metotrexato , Antimetabólitos Antineoplásicos/uso terapêutico , Creatinina , Estudos Retrospectivos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Síndromes Neurotóxicas/epidemiologia , Síndromes Neurotóxicas/etiologia
19.
Ann Surg ; 278(5): e995-e1002, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36805578

RESUMO

INTRODUCTION: The opioid epidemic is a public health issue in the United States. The objective of this study was to evaluate the association between naloxone coprescription mandates and postoperative outcomes. BACKGROUND: Data on naloxone coprescription mandates show mixed evidence for fatal overdoses in the broader population. How these mandates have impacted surgical patients has not been fully explored. METHODS: Healthcare claims data were used to identify all patients undergoing 1 of 50 common procedures between January 1, 2004, and June 30, 2019, and categorized as high risk for opioid overdose. The primary outcomes were an emergency department visit or hospital admission within 30 postoperative days. To reduce confounding, the association between this outcome and the implementation of naloxone coprescription mandates was estimated using a difference-in-differences approach. RESULTS: The study included 429,878 surgical patients with an average age of 54.8 years (SD=15.9 years) and with 257,728 females (60.0%). There was no significant association between naloxone prescribing mandates and the primary outcomes. After adjustment for potential confounders, the incidence of hospital admission was 3.26% after implementation of a naloxone coprescription mandate compared with 3.33% before (difference change: -0.08%, 95% CI: -0.44% to 0.29%, P =0.68). The incidence of an emergency department visit was 7.06% after implementation of a naloxone coprescription mandate compared with 7.73% before (difference: -0.67%, 95% CI: -1.39% to 0.05%, P =0.07). These results were robust to a variety of sensitivity and subgroup analyses. CONCLUSIONS: Naloxone coprescription mandates were not associated with a statistically or clinically significant change in emergency department visits or hospital admissions within 30 postoperative days.


Assuntos
Overdose de Drogas , Naloxona , Feminino , Humanos , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Naloxona/uso terapêutico , Analgésicos Opioides/uso terapêutico , Hospitalização , Serviço Hospitalar de Emergência
20.
Cytotherapy ; 25(9): 1006-1015, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37061898

RESUMO

BACKGROUND AIMS: In-process monitoring and control of biomanufacturing workflows remains a significant challenge in the development, production, and application of cell therapies. New process analytical technologies must be developed to identify and control the critical process parameters that govern ex vivo cell growth and differentiation to ensure consistent and predictable safety, efficacy, and potency of clinical products. METHODS: This study demonstrates a new platform for at-line intracellular analysis of T-cells. Untargeted mass spectrometry analyses via the platform are correlated to conventional methods of T-cell assessment. RESULTS: Spectral markers and metabolic pathways correlated with T-cell activation and differentiation are detected at early time points via rapid, label-free metabolic measurements from a minimal number of cells as enabled by the platform. This is achieved while reducing the analytical time and resources as compared to conventional methods of T-cell assessment. CONCLUSIONS: In addition to opportunities for fundamental insight into the dynamics of T-cell processes, this work highlights the potential of in-process monitoring and dynamic feedback control strategies via metabolic modulation to drive T-cell activation, proliferation, and differentiation throughout biomanufacturing.


Assuntos
Redes e Vias Metabólicas , Linfócitos T , Espectrometria de Massas , Diferenciação Celular , Proliferação de Células
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