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1.
Cell ; 186(16): 3499-3518.e14, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37437571

RESUMO

Chloroplasts are eukaryotic photosynthetic organelles that drive the global carbon cycle. Despite their importance, our understanding of their protein composition, function, and spatial organization remains limited. Here, we determined the localizations of 1,034 candidate chloroplast proteins using fluorescent protein tagging in the model alga Chlamydomonas reinhardtii. The localizations provide insights into the functions of poorly characterized proteins; identify novel components of nucleoids, plastoglobules, and the pyrenoid; and reveal widespread protein targeting to multiple compartments. We discovered and further characterized cellular organizational features, including eleven chloroplast punctate structures, cytosolic crescent structures, and unexpected spatial distributions of enzymes within the chloroplast. We also used machine learning to predict the localizations of other nuclear-encoded Chlamydomonas proteins. The strains and localization atlas developed here will serve as a resource to accelerate studies of chloroplast architecture and functions.


Assuntos
Vias Biossintéticas , Chlamydomonas reinhardtii , Proteínas de Cloroplastos , Chlamydomonas reinhardtii/metabolismo , Proteínas de Cloroplastos/metabolismo , Cloroplastos/metabolismo , Fotossíntese
2.
Cell ; 179(2): 417-431.e19, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31585081

RESUMO

Severe asthma patients with low type 2 inflammation derive less clinical benefit from therapies targeting type 2 cytokines and represent an unmet need. We show that mast cell tryptase is elevated in severe asthma patients independent of type 2 biomarker status. Active ß-tryptase allele count correlates with blood tryptase levels, and asthma patients carrying more active alleles benefit less from anti-IgE treatment. We generated a noncompetitive inhibitory antibody against human ß-tryptase, which dissociates active tetramers into inactive monomers. A 2.15 Å crystal structure of a ß-tryptase/antibody complex coupled with biochemical studies reveal the molecular basis for allosteric destabilization of small and large interfaces required for tetramerization. This anti-tryptase antibody potently blocks tryptase enzymatic activity in a humanized mouse model, reducing IgE-mediated systemic anaphylaxis, and inhibits airway tryptase in Ascaris-sensitized cynomolgus monkeys with favorable pharmacokinetics. These data provide a foundation for developing anti-tryptase as a clinical therapy for severe asthma.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Asma/terapia , Mastócitos/enzimologia , Mastócitos/imunologia , Triptases/antagonistas & inibidores , Triptases/imunologia , Adolescente , Regulação Alostérica/imunologia , Animais , Linhagem Celular , Feminino , Humanos , Macaca fascicularis , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Camundongos SCID , Coelhos
4.
Nature ; 628(8009): 804-810, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38538783

RESUMO

Sugarcane, the world's most harvested crop by tonnage, has shaped global history, trade and geopolitics, and is currently responsible for 80% of sugar production worldwide1. While traditional sugarcane breeding methods have effectively generated cultivars adapted to new environments and pathogens, sugar yield improvements have recently plateaued2. The cessation of yield gains may be due to limited genetic diversity within breeding populations, long breeding cycles and the complexity of its genome, the latter preventing breeders from taking advantage of the recent explosion of whole-genome sequencing that has benefited many other crops. Thus, modern sugarcane hybrids are the last remaining major crop without a reference-quality genome. Here we take a major step towards advancing sugarcane biotechnology by generating a polyploid reference genome for R570, a typical modern cultivar derived from interspecific hybridization between the domesticated species (Saccharum officinarum) and the wild species (Saccharum spontaneum). In contrast to the existing single haplotype ('monoploid') representation of R570, our 8.7 billion base assembly contains a complete representation of unique DNA sequences across the approximately 12 chromosome copies in this polyploid genome. Using this highly contiguous genome assembly, we filled a previously unsized gap within an R570 physical genetic map to describe the likely causal genes underlying the single-copy Bru1 brown rust resistance locus. This polyploid genome assembly with fine-grain descriptions of genome architecture and molecular targets for biotechnology will help accelerate molecular and transgenic breeding and adaptation of sugarcane to future environmental conditions.


Assuntos
Genoma de Planta , Poliploidia , Saccharum , Cromossomos de Plantas/genética , Genoma de Planta/genética , Haplótipos/genética , Hibridização Genética/genética , Melhoramento Vegetal , Saccharum/classificação , Saccharum/genética , Biotecnologia , Padrões de Referência , DNA de Plantas/genética
5.
Nat Chem Biol ; 20(3): 291-301, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37770698

RESUMO

Diverse mechanisms have been described for selective enrichment of biomolecules in membrane-bound organelles, but less is known about mechanisms by which molecules are selectively incorporated into biomolecular assemblies such as condensates that lack surrounding membranes. The chemical environments within condensates may differ from those outside these bodies, and if these differed among various types of condensate, then the different solvation environments would provide a mechanism for selective distribution among these intracellular bodies. Here we use small molecule probes to show that different condensates have distinct chemical solvating properties and that selective partitioning of probes in condensates can be predicted with deep learning approaches. Our results demonstrate that different condensates harbor distinct chemical environments that influence the distribution of molecules, show that clues to condensate chemical grammar can be ascertained by machine learning and suggest approaches to facilitate development of small molecule therapeutics with optimal subcellular distribution and therapeutic benefit.


Assuntos
Condensados Biomoleculares , Aprendizado de Máquina
6.
Blood ; 141(11): 1316-1321, 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36493342

RESUMO

Myelodysplastic neoplasms (MDSs) and chronic myelomonocytic leukemia (CMML) are clonal disorders driven by progressively acquired somatic mutations in hematopoietic stem cells (HSCs). Hypomethylating agents (HMAs) can modify the clinical course of MDS and CMML. Clinical improvement does not require eradication of mutated cells and may be related to improved differentiation capacity of mutated HSCs. However, in patients with established disease it is unclear whether (1) HSCs with multiple mutations progress through differentiation with comparable frequency to their less mutated counterparts or (2) improvements in peripheral blood counts following HMA therapy are driven by residual wild-type HSCs or by clones with particular combinations of mutations. To address these questions, the somatic mutations of individual stem cells, progenitors (common myeloid progenitors, granulocyte monocyte progenitors, and megakaryocyte erythroid progenitors), and matched circulating hematopoietic cells (monocytes, neutrophils, and naïve B cells) in MDS and CMML were characterized via high-throughput single-cell genotyping, followed by bulk analysis in immature and mature cells before and after AZA treatment. The mutational burden was similar throughout differentiation, with even the most mutated stem and progenitor clones maintaining their capacity to differentiate to mature cell types in vivo. Increased contributions from productive mutant progenitors appear to underlie improved hematopoiesis in MDS following HMA therapy.


Assuntos
Leucemia Mielomonocítica Crônica , Síndromes Mielodisplásicas , Humanos , Leucemia Mielomonocítica Crônica/tratamento farmacológico , Leucemia Mielomonocítica Crônica/genética , Leucemia Mielomonocítica Crônica/metabolismo , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética , Células-Tronco Hematopoéticas/metabolismo , Monócitos , Células Clonais
7.
Mol Psychiatry ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38355787

RESUMO

Individuals suffering from chronic pain develop substance use disorders (SUDs) more often than others. Understanding the shared genetic influences underlying the comorbidity between chronic pain and SUDs will lead to a greater understanding of their biology. Genome-wide association statistics were obtained from the UK Biobank for multisite chronic pain (MCP, Neffective = 387,649) and from the Million Veteran Program and the Psychiatric Genomics Consortium meta-analyses for alcohol use disorder (AUD, Neffective = 296,974), cannabis use disorder (CanUD, Neffective = 161,053), opioid use disorder (OUD, Neffective = 57,120), and problematic tobacco use (PTU, Neffective = 270,120). SNP-based heritability was estimated for each of the traits and genetic correlation (rg) analyses were performed to assess MCP-SUD pleiotropy. Bidirectional Mendelian Randomization analyses evaluated possible causal relationships. Finally, to identify and characterize individual loci, we performed a genome-wide pleiotropy analysis and a brain-wide analysis using imaging phenotypes available from the UK Biobank. MCP was positively genetically correlated with AUD (rg = 0.26, p = 7.55 × 10-18), CanUD (rg = 0.37, p = 8.21 × 10-37), OUD (rg = 0.20, p = 1.50 × 10-3), and PTU (rg = 0.29, p = 8.53 × 10-12). Although the MR analyses supported bi-directional relationships, MCP had larger effects on AUD (pain-exposure: beta = 0.18, p = 8.21 × 10-4; pain-outcome: beta = 0.07, p = 0.018), CanUD (pain-exposure: beta = 0.58, p = 2.70 × 10-6; pain-outcome: beta = 0.05, p = 0.014) and PTU (pain-exposure: beta = 0.43, p = 4.16 × 10-8; pain-outcome: beta = 0.09, p = 3.05 × 10-6) than the reverse. The genome-wide analysis identified two SNPs pleiotropic between MCP and all SUD investigated: IHO1 rs7652746 (ppleiotropy = 2.69 × 10-8), and CADM2 rs1248857 (ppleiotropy = 1.98 × 10-5). In the brain-wide analysis, rs7652746 was associated with multiple cerebellum and amygdala imaging phenotypes. When analyzing MCP pleiotropy with each SUD separately, we found 25, 22, and 4 pleiotropic variants for AUD, CanUD, and OUD, respectively. To our knowledge, this is the first large-scale study to provide evidence of potential causal relationships and shared genetic mechanisms underlying MCP-SUD comorbidity.

8.
Int J Neuropsychopharmacol ; 27(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38315678

RESUMO

BACKGROUND: Previous preclinical and human studies have shown that a high-fat ketogenic diet and ketone supplements (KS) are efficacious in reducing alcohol craving, alcohol consumption, and signs of alcohol withdrawal. However, the effects of KS on alcohol sensitivity are unknown. METHODS: In this single-blind, cross-over study, 10 healthy participants (3 females) were administered a single, oral dose of a KS (25 g of ketones from D-ß-hydroxybutyric acid and R-1,3-butanediol) or placebo 30 minutes before an oral alcohol dose (0.25 g/kg for women; 0.31 g/kg for men). Assessments of breath alcohol concentration and blood alcohol levels (BAL) and responses on the Drug Effect Questionnaire were repeatedly obtained over 180 minutes after alcohol consumption. In a parallel preclinical study, 8 Wistar rats (4 females) received an oral gavage of KS (0.42 g ketones/kg), water, or the sweetener allulose (0.58 g/kg) followed 15 minutes later by an oral alcohol dose (0.8 g/kg). BAL was monitored for 240 minutes after alcohol exposure. RESULTS: In humans, the intake of KS before alcohol significantly blunted breath alcohol concentration and BAL, reduced ratings of alcohol liking and wanting more, and increased disliking for alcohol. In rats, KS reduced BAL more than either allulose or water. CONCLUSION: KS altered physiological and subjective responses to alcohol in both humans and rats, and the effects were likely not mediated by the sweetener allulose present in the KS drink. Therefore, KS could potentially reduce the intoxicating effects of alcohol.


Assuntos
Alcoolismo , Síndrome de Abstinência a Substâncias , Masculino , Humanos , Ratos , Feminino , Animais , Estudos Cross-Over , Cetonas/farmacologia , Voluntários Saudáveis , Método Simples-Cego , Ratos Wistar , Etanol/farmacologia , Edulcorantes , Concentração Alcoólica no Sangue , Suplementos Nutricionais , Água
9.
Psychol Med ; 54(8): 1779-1786, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38317430

RESUMO

BACKGROUND: Elucidation of the interaction of biological and psychosocial/environmental factors on opioid dependence (OD) risk can inform our understanding of the etiology of OD. We examined the role of psychosocial/environmental factors in moderating polygenic risk for opioid use disorder (OUD). METHODS: Data from 1958 European ancestry adults who participated in the Yale-Penn 3 study were analyzed. Polygenic risk scores (PRS) were based on a large-scale multi-trait analysis of genome-wide association studies (MTAG) of OUD. RESULTS: A total of 420 (21.1%) individuals had a lifetime diagnosis of OD. OUD PRS were positively associated with OD (odds ratio [OR] 1.42, 95% confidence interval [CI] 1.21-1.66). Household income and education were the strongest correlates of OD. Among individuals with higher OUD PRS, those with higher education level had lower odds of OD (OR 0.92, 95% CI 0.85-0.98); and those with posttraumatic stress disorder (PTSD) were more likely to have OD relative to those without PTSD (OR 1.56, 95% CI 1.04-2.35). CONCLUSIONS: Results suggest an interplay between genetics and psychosocial environment in contributing to OD risk. While PRS alone do not yet have useful clinical predictive utility, psychosocial factors may help enhance prediction. These findings could inform more targeted clinical and policy interventions to help address this public health crisis.


Assuntos
Estudo de Associação Genômica Ampla , Herança Multifatorial , Transtornos Relacionados ao Uso de Opioides , Humanos , Masculino , Transtornos Relacionados ao Uso de Opioides/genética , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Feminino , Adulto , Pessoa de Meia-Idade , Fatores de Risco , Predisposição Genética para Doença , Transtornos de Estresse Pós-Traumáticos/genética , Transtornos de Estresse Pós-Traumáticos/epidemiologia , População Branca/genética , Escolaridade , Interação Gene-Ambiente
10.
Nat Chem Biol ; 18(12): 1298-1306, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35761089

RESUMO

Biomolecular condensates compartmentalize and regulate assemblies of biomolecules engaged in vital physiological processes in cells. Specific proteins and nucleic acids engaged in shared functions occur in any one kind of condensate, suggesting that these compartments have distinct chemical specificities. Indeed, some small-molecule drugs concentrate in specific condensates due to chemical properties engendered by particular amino acids in the proteins in those condensates. Here we argue that the chemical properties that govern molecular interactions between a small molecule and biomolecules within a condensate can be ascertained for both the small molecule and the biomolecules. We propose that learning this 'chemical grammar', the rules describing the chemical features of small molecules that engender attraction or repulsion by the physicochemical environment of a specific condensate, should enable design of drugs with improved efficacy and reduced toxicity.


Assuntos
Condensados Biomoleculares , Proteínas , Proteínas/química
11.
Immunity ; 42(4): 704-18, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25840682

RESUMO

B helper follicular T (Tfh) cells are critical for long-term humoral immunity. However, it remains unclear how these cells are recruited and contribute to secondary immune responses. Here we show that primary Tfh cells segregate into follicular mantle (FM) and germinal center (GC) subpopulations that display distinct gene expression signatures. Restriction of the primary Tfh cell subpopulation in the GC was mediated by downregulation of chemotactic receptor EBI2. Following collapse of the GC, memory T cells persisted in the outer follicle where they scanned CD169(+) subcapsular sinus macrophages. Reactivation and intrafollicular expansion of these follicular memory T cells in the subcapsular region was followed by their extrafollicular dissemination via the lymphatic flow. These data suggest that Tfh cells integrate their antigen-experience history to focus T cell help within the GC during primary responses but act rapidly to provide systemic T cell help after re-exposure to the antigen.


Assuntos
Linfócitos B/citologia , Linhagem da Célula/imunologia , Centro Germinativo/citologia , Imunidade Humoral , Linfócitos T Auxiliares-Indutores/citologia , Animais , Linfócitos B/imunologia , Diferenciação Celular , Linhagem da Célula/genética , Movimento Celular/imunologia , Proliferação de Células , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Centro Germinativo/imunologia , Memória Imunológica , Camundongos , Camundongos Knockout , Cultura Primária de Células , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/imunologia , Lectina 1 Semelhante a Ig de Ligação ao Ácido Siálico/genética , Lectina 1 Semelhante a Ig de Ligação ao Ácido Siálico/imunologia , Transdução de Sinais , Linfócitos T Auxiliares-Indutores/imunologia
12.
J Org Chem ; 89(9): 5927-5940, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38651750

RESUMO

A key factor in the development of selective nucleophilic addition to allenamides is controlling the reactivity of electrophilic intermediates, which is generally achieved using an electrophilic activator via conjugated iminium intermediates. In this combined experimental and computational study, we show that a general and highly chemoselective hydroamination of allenamides can be accomplished using a combination of 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) and NaOAc. Experimental mechanistic studies revealed that HFIP mediates proton transfer to activate the allenamide, while the acetate additive significantly contributes to N-selective interception. This strategy enables a general hydroamination of allenamides without the use of metals. We demonstrated that various functionalized 1,3-diamines could be readily synthesized and diversified into value-added structural motifs. Detailed mechanistic investigations using the density functional theory revealed the role of NaOAc in the formation of reactive electrophilic intermediates, which ultimately governed the selective formation of 1,3-diamine products. Critically, calculations of the potential energy surface around the proton-transfer transition state revealed that two different reactive electrophilic intermediates were formed when NaOAc was added.

13.
J Pathol ; 261(4): 413-426, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37768107

RESUMO

Integration and mining of bioimaging data remains a challenge and lags behind the rapidly expanding digital pathology field. We introduce Hourglass, an open-access analytical framework that streamlines biology-driven visualization, interrogation, and statistical assessment of multiparametric datasets. Cognizant of tissue and clinical heterogeneity, Hourglass systematically organizes observations across spatial and global levels and within patient subgroups. Applied to an extensive bioimaging dataset, Hourglass promptly consolidated a breadth of known interleukin-6 (IL-6) functions via its downstream effector STAT3 and uncovered a so-far unknown sexual dimorphism in the IL-6/STAT3-linked intratumoral T-cell response in human pancreatic cancer. As an R package and cross-platform application, Hourglass facilitates knowledge extraction from multi-layered bioimaging datasets for users with or without computational proficiency and provides unique and widely accessible analytical means to harness insights hidden within heterogeneous tissues at the sample and patient level. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Interleucina-6 , Neoplasias Pancreáticas , Humanos , Interleucina-6/genética , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Fenótipo , Reino Unido , Fator de Transcrição STAT3/genética
14.
Alcohol Alcohol ; 59(3)2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38606931

RESUMO

AIMS: Among individuals with alcohol use disorder (AUD), sleep disturbances are pervasive and contribute to the etiology and maintenance of AUD. However, despite increased attention toward the relationship between alcohol use and sleep, limited empirical research has systematically examined whether reductions in drinking during treatment for AUD are associated with improvements in sleep problems. METHODS: We used data from a multisite, randomized, controlled trial that compared 6 months of treatment with gabapentin enacarbil extended-release with placebo for adults with moderate-to-severe AUD (N = 346). The Timeline Follow-back was used to assess WHO risk drinking level reductions and the Pittsburgh Sleep Quality Index was used to assess sleep quality over the prior month at baseline and the end of treatment. RESULTS: Sleep problem scores in the active medication and placebo groups improved equally. Fewer sleep problems were noted among individuals who achieved at least a 1-level reduction (B = -0.99, 95% confidence interval (CI) [-1.77, -0.20], P = .014) or at least a 2-level reduction (B = -0.80, 95% CI [-1.47, -0.14], P = .018) in WHO risk drinking levels at the end of treatment. Reductions in drinking, with abstainers excluded from the analysis, also predicted fewer sleep problems at the end of treatment (1-level: B = -1.01, 95% CI [-1.83, -0.20], P = .015; 2-level: B = -0.90, 95% CI [-1.59, -0.22], P = .010). CONCLUSIONS: Drinking reductions, including those short of abstinence, are associated with improvements in sleep problems during treatment for AUD. Additional assessment of the causal relationships between harm-reduction approaches to AUD and improvements in sleep is warranted.


Assuntos
Alcoolismo , Adulto , Humanos , Consumo de Bebidas Alcoólicas/terapia , Alcoolismo/complicações , Alcoolismo/tratamento farmacológico , Organização Mundial da Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Ann Intern Med ; 176(3): 289-297, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36716451

RESUMO

BACKGROUND: Studies have shown that magnetic resonance imaging (MRI) does not have clinically important effects on the device parameters of non-MRI-conditional implantable cardioverter-defibrillators (ICDs). However, data on non-MRI-conditional ICD detection and treatment of arrhythmias after MRI are limited. OBJECTIVE: To examine if non-MRI-conditional ICDs have preserved shock function of arrhythmias after MRI. DESIGN: Prospective cohort study. (ClinicalTrials.gov: NCT01130896). SETTING: 1 center in the United States. PATIENTS: 629 patients with non-MRI-conditional ICDs enrolled consecutively between February 2003 and January 2015. INTERVENTIONS: 813 total MRI examinations at a magnetic field strength of 1.5 Tesla using a prespecified safety protocol. MEASUREMENTS: Implantable cardioverter-defibrillator interrogations were collected after MRI. Clinical outcomes included arrhythmia detection and treatment, generator or lead exchanges, adverse events, and death. RESULTS: During a median follow-up of 2.2 years from MRI to latest available ICD interrogation before generator or lead exchange in 536 patients, 4177 arrhythmia episodes were detected, and 97 patients received ICD shocks. Sixty-one patients (10% of total) had 130 spontaneous ventricular tachycardia or fibrillation events terminated by ICD shocks. A total of 210 patients (33% of total) are known to have died (median, 1.7 years from MRI to death); 3 had cardiac arrhythmia deaths where shocks were indicated without direct evidence of device dysfunction. LIMITATIONS: Data were acquired at a single center and may not be generalizable to other clinical settings and MRI facilities. Implantable cardioverter-defibrillator interrogations were not available for a subset of patients; adjudication of cause of death relied solely on death certificate data in a subset. CONCLUSION: Non-MRI-conditional ICDs appropriately treated detected tachyarrhythmias after MRI. No serious adverse effects on device function were reported after MRI. PRIMARY FUNDING SOURCE: Johns Hopkins University and National Institutes of Health.


Assuntos
Desfibriladores Implantáveis , Humanos , Arritmias Cardíacas/terapia , Causas de Morte , Morte Súbita Cardíaca/prevenção & controle , Morte Súbita Cardíaca/etiologia , Desfibriladores Implantáveis/efeitos adversos , Imageamento por Ressonância Magnética/efeitos adversos , Imageamento por Ressonância Magnética/métodos , Estudos Prospectivos , Resultado do Tratamento
16.
Proc Natl Acad Sci U S A ; 118(11)2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33692125

RESUMO

Rare genetic mutations result in aggregation and spreading of cognate proteins in neurodegenerative disorders; however, in the absence of mutation (i.e., in the vast majority of "sporadic" cases), mechanisms for protein misfolding/aggregation remain largely unknown. Here, we show environmentally induced nitrosative stress triggers protein aggregation and cell-to-cell spread. In patient brains with amyotrophic lateral sclerosis (ALS)/frontotemporal dementia (FTD), aggregation of the RNA-binding protein TDP-43 constitutes a major component of aberrant cytoplasmic inclusions. We identify a pathological signaling cascade whereby reactive nitrogen species cause S-nitrosylation of TDP-43 (forming SNO-TDP-43) to facilitate disulfide linkage and consequent TDP-43 aggregation. Similar pathological SNO-TDP-43 levels occur in postmortem human FTD/ALS brains and in cell-based models, including human-induced pluripotent stem cell (hiPSC)-derived neurons. Aggregated TDP-43 triggers additional nitrosative stress, representing positive feed forward leading to further SNO-TDP-43 formation and disulfide-linked oligomerization/aggregation. Critically, we show that these redox reactions facilitate cell spreading in vivo and interfere with the TDP-43 RNA-binding activity, affecting SNMT1 and phospho-(p)CREB levels, thus contributing to neuronal damage in ALS/FTD disorders.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Proteínas de Ligação a DNA/metabolismo , Demência Frontotemporal/metabolismo , S-Nitrosotióis/metabolismo , Esclerose Lateral Amiotrófica/patologia , Encéfalo/metabolismo , Encéfalo/patologia , Cisteína/metabolismo , Proteínas de Ligação a DNA/química , Demência Frontotemporal/patologia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Neurônios Motores/metabolismo , Óxido Nítrico/metabolismo , Agregação Patológica de Proteínas , Processamento Pós-Transcricional do RNA , Espécies Reativas de Nitrogênio/metabolismo , S-Nitrosotióis/química , Estresse Fisiológico
17.
Am J Drug Alcohol Abuse ; : 1-11, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39018668

RESUMO

Background: Substance use disorders (SUDs) are heterogeneous across multiple functional domains. Various frameworks posit that domains (e.g., executive function) contribute to the persistence of SUDs; however, the domains identified in different studies vary.Objectives: We used factor analysis to identify the underlying latent domains present in a large sample (N = 5,244, 55.8% male) with a variety of SUDs to yield findings more generalizable than studies with a narrower focus.Method: Participants (1,384 controls and 3,860 participants with one or more SUDs including alcohol, cocaine, cannabis, and/or opioid use disorders) completed the Semi-Structured Assessment for Drug Dependence and Alcoholism, the NEO Personality Inventory, and the Wisconsin Card Sorting Test. Exploratory factor analysis (EFA) and fit indices (root mean-squared error of approximation (RMSEA), Comparative Fit Index (CFI), and Tucker-Lewis Index (TLI)) were used to examine different latent variable models. A multiple indicators, multiple causes (MIMIC) approach-tested associations of the latent variables with sociodemographics, substance use, and a history of abuse/neglect.Results: A six-factor model (predominant alcohol, predominant cocaine, predominant opioid, externalizing, personality, and executive function) provided the best fit [RMSEA = 0.063 (90% CI 0.060, 0.066), CFI = 0.98, TLI = 0.96]. All factors were moderately correlated (coefficient = 0.25-0.55, p < .05) with the exception of executive function. MIMIC analysis revealed different patterns of associations (all p < .0001) with sociodemographics, substance use, and a history of abuse/neglect among the factors.Conclusions: The domains identified, particularly executive function, were parallel to those observed previously. These factors underscore the heterogeneous nature of SUDs and may be useful in developing more targeted clinical interventions.

18.
J Arthroplasty ; 39(7): 1747-1751, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38253188

RESUMO

BACKGROUND: Femoral neck fractures are common in individuals over 65, necessitating quick mobilization for the best outcomes. There's ongoing debate about the optimal femoral component fixation method in total hip arthroplasty (THA) for these fractures. Recent U.S. data shows a preference for cementless techniques in over 93% of primary THAs. Nonetheless, cemented fixation might offer advantages like fewer revisions, reduced periprosthetic fractures, lesser thigh pain, and enhanced long-term implant survival for those above 65. This study compares cementless and cemented fixation methods in THA, focusing on postoperative complications in patients aged 65 and older. METHODS: We analyzed a national database to identify patients aged 65+ who underwent primary THA for femoral neck fractures between 2016 and 2021, using either cementless (n = 2,842) or cemented (n = 1,124) techniques. A 1:1 propensity-matched analysis was conducted to balance variables such as age, sex, and comorbidities, resulting in two equally sized groups (n = 1,124 each). We evaluated outcomes like infection, venous thromboembolism (VTE), wound issues, dislocation, periprosthetic fracture, etc., at 90 days, 1 year, and 2 years post-surgery. A P-value < 05 indicated statistical significance. RESULTS: The cemented group initially consisted of older individuals, more females, and higher comorbidity rates. Both groups had similar infection and wound complication rates, and aseptic loosening. The cemented group, however, had lower periprosthetic fracture rates (2.5 versus 4.4%, P = .02) and higher VTE rates (2.9 versus 1.2%, P = .01) at 90 days. After 1 and 2 years, the cementless group experienced more aseptic revision surgeries. CONCLUSIONS: This study, using a large, national database and propensity-matched cohorts, indicates that cemented femoral component fixation in THA leads to fewer periprosthetic fractures and aseptic revisions, but a higher VTE risk. Fixation type choice should consider various factors, including age, sex, comorbidities, bone quality, and surgical expertise. This data can inform surgeons in their decision-making process.


Assuntos
Artroplastia de Quadril , Cimentos Ósseos , Fraturas do Colo Femoral , Complicações Pós-Operatórias , Humanos , Artroplastia de Quadril/métodos , Artroplastia de Quadril/efeitos adversos , Idoso , Feminino , Masculino , Fraturas do Colo Femoral/cirurgia , Idoso de 80 Anos ou mais , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Fraturas Periprotéticas/etiologia , Fraturas Periprotéticas/epidemiologia , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Resultado do Tratamento , Prótese de Quadril/efeitos adversos , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/efeitos adversos
19.
J Med Syst ; 48(1): 57, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801649

RESUMO

Wearable electronics are increasingly common and useful as health monitoring devices, many of which feature the ability to record a single-lead electrocardiogram (ECG). However, recording the ECG commonly requires the user to touch the device to complete the lead circuit, which prevents continuous data acquisition. An alternative approach to enable continuous monitoring without user initiation is to embed the leads in a garment. This study assessed ECG data obtained from the YouCare device (a novel sensorized garment) via comparison with a conventional Holter monitor. A cohort of thirty patients (age range: 20-82 years; 16 females and 14 males) were enrolled and monitored for twenty-four hours with both the YouCare device and a Holter monitor. ECG data from both devices were qualitatively assessed by a panel of three expert cardiologists and quantitatively analyzed using specialized software. Patients also responded to a survey about the comfort of the YouCare device as compared to the Holter monitor. The YouCare device was assessed to have 70% of its ECG signals as "Good", 12% as "Acceptable", and 18% as "Not Readable". The R-wave, independently recorded by the YouCare device and Holter monitor, were synchronized within measurement error during 99.4% of cardiac cycles. In addition, patients found the YouCare device more comfortable than the Holter monitor (comfortable 22 vs. 5 and uncomfortable 1 vs. 18, respectively). Therefore, the quality of ECG data collected from the garment-based device was comparable to a Holter monitor when the signal was sufficiently acquired, and the garment was also comfortable.


Assuntos
Eletrocardiografia Ambulatorial , Eletrocardiografia , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Adulto , Eletrocardiografia Ambulatorial/instrumentação , Eletrocardiografia Ambulatorial/métodos , Idoso de 80 Anos ou mais , Eletrocardiografia/instrumentação , Eletrocardiografia/métodos , Dispositivos Eletrônicos Vestíveis , Adulto Jovem , Vestuário , Processamento de Sinais Assistido por Computador/instrumentação
20.
Breast Cancer Res Treat ; 199(2): 243-252, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36944848

RESUMO

BACKGROUND: The primary aim of this randomized neoadjuvant trial in operable, HER2-positive breast cancer, was to determine the efficacy on pathologic complete response (pCR) of substituting lapatinib (L) for trastuzumab (T) or adding L to T, in combination with weekly paclitaxel (WP) following AC. Results on pCR were previously reported. Here, we report data on planned secondary endpoints, recurrence-free interval (RFI) post-surgery, and overall survival (OS). METHODS: All patients received standard AC q3 weeks × 4 cycles followed by WP (80 mg/m2) on days 1, 8, and 15, q28 days × 4 cycles. Concurrently with WP, patients received either T (4 mg/kg load, then 2 mg/kg) weekly until surgery, L (1250 mg) daily until surgery, or weekly T plus L (750 mg) daily until surgery. Following surgery, all patients received T to complete 52 weeks of HER2-targeted therapy. 522 of 529 randomized patients had follow-up. Median follow-up was 5.1 years. RESULTS: RFI at 4.5 years was 87.2%, 79.4% (p = 0.34; HR = 1.37; 95% CI 0.80, 2.34), and 89.4% (p = 0.37; HR = 0.70; 0.37, 1.32) for arms T, L, and TL, respectively. The corresponding five-year OS was 94.8%, 89.1% (p = 0.34; HR = 1.46; 0.68, 3.11), and 95.8% (p = 0.25; HR = 0.58; 0.22, 1.51), respectively. Patients with pCR had a much better prognosis, especially in the ER-negative cohort: RFI (HR = 0.23, p < 0.001) and OS (HR = 0.28, p < 0.001). CONCLUSIONS: Although pCR, RFI, and OS were numerically better with the dual combination and less with L, the differences were not statistically significant. However, achievement of pCR again correlated with improved outcomes, especially remarkable in the ER-negative subset. CLINICAL TRIALS REGISTRATION: NCT00486668.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/patologia , Terapia Neoadjuvante/efeitos adversos , Paclitaxel/uso terapêutico , Receptor ErbB-2 , Trastuzumab/uso terapêutico , Resultado do Tratamento
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