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1.
Front Bioeng Biotechnol ; 12: 1422235, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39157442

RESUMEN

Spheroids have become principal three-dimensional models to study cancer, developmental processes, and drug efficacy. Single-cell analysis techniques have emerged as ideal tools to gauge the complexity of cellular responses in these models. However, the single-cell quantitative assessment based on 3D-microscopic data of the subcellular distribution of fluorescence markers, such as the nuclear/cytoplasm ratio of transcription factors, has largely remained elusive. For spheroid generation, ultra-low attachment plates are noteworthy due to their simplicity, compatibility with automation, and experimental and commercial accessibility. However, it is unknown whether and to what degree the plate type impacts spheroid formation and biology. This study developed a novel AI-based pipeline for the analysis of 3D-confocal data of optically cleared large spheroids at the wholemount, single-cell, and sub-cellular levels. To identify relevant samples for the pipeline, automated brightfield microscopy was employed to systematically compare the size and eccentricity of spheroids formed in six different plate types using four distinct human cell lines. This showed that all plate types exhibited similar spheroid-forming capabilities and the gross patterns of growth or shrinkage during 4 days after seeding were comparable. Yet, size and eccentricity varied systematically among specific cell lines and plate types. Based on this prescreen, spheroids of HaCaT keratinocytes and HT-29 cancer cells were further assessed. In HaCaT spheroids, the in-depth analysis revealed a correlation between spheroid size, cell proliferation, and the nuclear/cytoplasm ratio of the transcriptional coactivator, YAP1, as well as an inverse correlation with respect to cell differentiation. These findings, yielded with a spheroid model and at a single-cell level, corroborate earlier concepts of the role of YAP1 in cell proliferation and differentiation of keratinocytes in human skin. Further, the results show that the plate type may influence the outcome of experimental campaigns and that it is advisable to scan different plate types for the optimal configuration during a specific investigation.

2.
EMBO J ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103491

RESUMEN

Mitochondrial DNA (mtDNA) is present in multiple copies within cells and is required for mitochondrial ATP generation. Even within individual cells, mtDNA copies can differ in their sequence, a state known as heteroplasmy. The principles underlying dynamic changes in the degree of heteroplasmy remain incompletely understood, due to the inability to monitor this phenomenon in real time. Here, we employ mtDNA-based fluorescent markers, microfluidics, and automated cell tracking, to follow mtDNA variants in live heteroplasmic yeast populations at the single-cell level. This approach, in combination with direct mtDNA tracking and data-driven mathematical modeling reveals asymmetric partitioning of mtDNA copies during cell division, as well as limited mitochondrial fusion and fission frequencies, as critical driving forces for mtDNA variant segregation. Given that our approach also facilitates assessment of segregation between intact and mutant mtDNA, we anticipate that it will be instrumental in elucidating the mechanisms underlying the purifying selection of mtDNA.

3.
Tob Control ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39134401

RESUMEN

OBJECTIVE: Places with more tobacco retailers have higher smoking prevalence levels, but whether this is because retailers locate where people who smoke live or whether tobacco availability prompts tobacco use is unknown. In this study, we compare the role of consumer demand with that of tobacco supply in longitudinal, area-based associations of tobacco retailer density with smoking prevalence. METHODS: We merged annual adult smoking prevalence estimates derived from the USA Behavioural Risk Factor Surveillance System data with annual county estimates of tobacco retailer density calculated from the National Establishment Time Series data for 3080 counties between 2000 and 2010. We analysed relationships between retailer density and smoking in 3080 counties, using random intercept cross-lagged panel models and employing two measures of tobacco retailer density capturing the number of likely tobacco retailers in a county divided by either the population or land area. RESULTS: Both density models provided evidence of significant demand and supply effects; in the population-based model, the association of smoking prevalence in 1 year with tobacco retailer density in the next year (standardised coefficient=0.038, p<0.01) was about double the association between tobacco retailer density with subsequent smoking prevalence (0.017, p<0.01). The reverse was true in the land area-based model, where the supply effect (0.042, p<0.01) was more than 10 times stronger than the demand effect (0.003, p<0.01). CONCLUSIONS: Policies that restrict access to retail tobacco have the potential to reduce smoking prevalence, but pairing such policies with interventions to reduce consumer demand remains important.

4.
JAMA Oncol ; 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39115975

RESUMEN

Importance: Postmastectomy radiation therapy (PMRT) improves local-regional disease control and patient survival. Hypofractionation (HF) regimens have comparable efficacy and complication rates with improved quality of life compared with conventional fractionation (CF) schedules. However, the use of HF after mastectomy in patients undergoing breast reconstruction has not been prospectively examined. Objective: To compare HF and CF PMRT outcomes after implant-based reconstruction. Design, Setting, and Participants: This randomized clinical trial assessed patients 18 years or older undergoing mastectomy and immediate expander or implant reconstruction for breast cancer (Tis, TX, or T1-3) and unilateral PMRT from March 8, 2018, to November 3, 2021 (median [range] follow-up, 40.4 [15.4-63.0] months), at 16 US cancer centers or hospitals. Analyses were conducted between September and December 2023. Interventions: Patients were randomized 1:1 to HF or CF PMRT. Chest wall doses were 4256 cGy for 16 fractions for HF and 5000 cGy for 25 fractions for CF. Chest wall toxic effects were defined as a grade 3 or higher adverse event. Main Outcomes and Measures: The primary outcome was the change in physical well-being (PWB) domain of the Functional Assessment of Cancer Therapy-Breast (FACT-B) quality-of-life assessment tool at 6 months after starting PMRT, controlling for age. Secondary outcomes included toxic effects and cancer recurrence. Results: Of 400 women (201 in the CF arm and 199 in the HF arm; median [range] age, 47 [23-79] years), 330 patients had PWB scores at baseline and at 6 months. There was no difference in the change in PWB between the study arms (estimate, 0.13; 95% CI, -0.86 to 1.11; P = .80), but there was a significant interaction between age group and study arm (P = .03 for interaction). Patients younger than 45 years had higher 6-month absolute PWB scores if treated with HF rather than CF regimens (23.6 [95% CI, 22.7-24.6] vs 22.0 [95% CI, 20.7-23.3]; P = .047) and reported being less bothered by adverse effects (mean [SD], 3.0 [0.9] in the HF arm and 2.6 [1.2] in the CF arm; P = .02) or nausea (mean [SD], 3.8 [0.4] in the HF arm and 3.6 [0.8] in the CF arm; P = .04). In the as-treated cohort, there were 23 distant (11 in the HF arm and 12 in the CF arm) and 2 local-regional (1 in the HF arm and 1 in the CF arm) recurrences. Chest wall toxic effects occurred in 39 patients (20 in the HF arm and 19 in the CF arm) at a median (IQR) of 7.2 (1.8-12.9) months. Fractionation was not associated with chest wall toxic effects on multivariate analysis (HF arm: hazard ratio, 1.02; 95% CI, 0.52-2.00; P = .95). Fewer patients undergoing HF vs CF regimens had a treatment break (5 [2.7%] vs 15 [7.7%]; P = .03) or required unpaid time off from work (17 [8.5%] vs 34 [16.9%]; P = .02). Conclusions and Relevance: In this randomized clinical trial, the HF regimen did not significantly improve change in PWB compared with the CF regimen. These data add to the increasing experience with HF PMRT in patients with implant-based reconstruction. Trial Registration: ClinicalTrials.gov Identifier: NCT03422003.

5.
J Parasitol ; 110(4): 311-338, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39034606

RESUMEN

The tadpole-dwelling pinworm, Gyrinicola batrachiensis (Walton, 1929) Adamson, 1981 was recognized as the sole representative of the genus across Canada and the United States. However, evaluation of the morphology of these parasites across their range revealed considerable morphological variability that suggested diagnosable morphotypes. These morphotypes were associated with different species of anurans, several of which occurred in sympatry. Herein we use an extensive geographic sampling across the United States to obtain the morphotypes, screen their genetic diversity, and analyze this information using an integrative approach. We reconstructed their phylogeny using nuclear ribosomal partial genes 18S and 28S, ITS1, 5.8S, and ITS2, as well as 5 mitochondrial genes generated with Next-Generation sequencing technology. This phylogeny reveals 3 well-resolved lineages, which upon the use of a statistical approach (bPTP [Bayesian implementation of the Poisson tree processes]) supports the delimitation of 4 distinct groups equivalent to species. These putative species groups were tested using morphological characteristics paired with a MANOVA and canonical variate analysis. Results suggest that at least 4 species of Gyrinicola are present within North America, resulting in the resurrection of G. armatus (Walton, 1933) and the description of 2 new species.


Asunto(s)
Teorema de Bayes , ADN de Helmintos , Variación Genética , Filogenia , Estados Unidos , Animales , ADN de Helmintos/química , Anuros/parasitología , Oxyuroidea/clasificación , Oxyuroidea/genética , Oxyuroidea/anatomía & histología , ARN Ribosómico 28S/genética , ADN Espaciador Ribosómico/genética , ADN Mitocondrial/química , ADN Mitocondrial/genética
6.
J Arthroplasty ; 2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38889806

RESUMEN

BACKGROUND: Obesity, defined as a body mass index (BMI) ≥ 30, is an ever-growing epidemic, with > 35% of adults in the United States currently classified as obese. Super-obese individuals, defined as those who have a BMI ≥ 50, are the fastest-growing portion of this group. This study sought to quantify the infection risk as well as the incidence of surgical, medical, and thromboembolic complications among super-obese patients undergoing total knee arthroplasty (TKA). METHODS: An all-payer claims database was used to identify patients who underwent elective, primary TKA between 2016 and 2021. Patients who had a BMI ≥ 50 were compared to those who had a normal BMI of 18 to 25. Demographics and the incidence of 90-days postoperative complications were compared between the 2 groups. Univariate analysis and multivariable regression were used to assess differences between groups. RESULTS: In total, 3,376 super-obese TKA patients were identified and compared to 17,659 patients who had a normal BMI. Multivariable analysis indicated that the super-obese cohort was at an increased postoperative risk of periprosthetic joint infection (adjusted odds ratio [aOR] 3.7, 95% confidence interval [CI]: 2.1 to 6.4, P < .001), pulmonary embolism (aOR 2.2, 95%-CI: 1.0 to 5.0, P = .047), acute respiratory failure (aOR 4.1, 95%-CI: 2.7 to 6.1, P < .001), myocardial infarction (aOR 2.5, 95%-CI: 1.1 to 5.8, P = .026), wound dehiscence (aOR 2.3, 95%-CI: 1.4 to 3.8, P = .001), and acute renal failure (aOR 3.2, 95%-CI: 2.4 to 4.2, P < .001) relative to patients who have normal BMI. CONCLUSIONS: Super-obese TKA patients are at an elevated risk of postoperative infectious, surgical, medical, and thromboembolic complications. As such, risk stratification, as well as appropriate medical management and optimization, is of utmost importance for this high-risk group.

7.
Tob Control ; 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-38937098

RESUMEN

OBJECTIVE: To examine inequities in tobacco retailer availability by neighbourhood-level socioeconomic, racial/ethnic and same-sex couple composition. DATA SOURCES: We conducted a 10 November 2022 search of PubMed, PsycINFO, Global Health, LILACS, Embase, ABI/Inform, CINAHL, Business Source Complete, Web of Science and Scopus. STUDY SELECTION: We included records from Organisation for Economic Co-operation and Development member countries that tested associations of area-level measures of tobacco retailer availability and neighbourhood-level sociodemographic characteristics. Two coders reviewed the full text of eligible records (n=58), including 41 records and 205 effect sizes for synthesis. DATA EXTRACTION: We used dual independent screening of titles, abstracts and full texts. One author abstracted and a second author confirmed the study design, location, unit of analysis, sample size, retailer data source, availability measure, statistical approach, sociodemographic characteristic and unadjusted effect sizes. DATA SYNTHESIS: Of the 124 effect sizes related to socioeconomic inequities (60.5% of all effect sizes), 101 (81.5%) indicated evidence of inequities. Of 205 effect sizes, 69 (33.7%) tested associations between retailer availability and neighbourhood composition of racially and ethnically minoritised people, and 57/69 (82.6%) documented inequities. Tobacco availability was greater in neighbourhoods with more Black, Hispanic/Latine and Asian residents (82.8%, 90.3% and 40.0% of effect sizes, respectively). Two effect sizes found greater availability with more same-sex households. CONCLUSIONS: There are stark inequities in tobacco retailer availability. Moving beyond documenting inequities to partnering with communities to design, implement, and evaluate interventions that reduce and eliminate inequities in retail availability is needed to promote an equitable retail environment. PROSPERO REGISTRATION NUMBER: CRD42019124984.

8.
Physiol Rev ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38900644

RESUMEN

Depending on cell type, environmental inputs, and disease, the cells in the human body can have widely different sizes. In recent years, it became clear that cell size is a major regulator of cell function. However, we are only beginning to understand how optimization of cell function determines a given cell's optimal size. Here, we review currently known size control strategies of eukaryotic cells, and the intricate link of cell size to intracellular biomolecular scaling, organelle homeostasis and cell cycle progression. We detail the cell size dependent regulation of early development and the impact of cell size on cell differentiation. Given the importance of cell size for normal cellular physiology, cell size control must account for changing environmental conditions. We describe how cells sense environmental stimuli, such as nutrient availability, and accordingly adapt their size by regulating cell growth and cell cycle progression. Moreover, we discuss the correlation of pathological states with misregulation of cell size, and how for a long time, this was considered a downstream consequence of cellular dysfunction. We review newer studies that reveal a reversed causality, with misregulated cell size leading to pathophysiological phenotypes such as senescence and aging. In summary, we highlight important roles of cell size in cellular function and dysfunction, which could have major implications for both diagnostics and treatment in the clinic.

9.
Front Cell Neurosci ; 18: 1422866, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38799983

RESUMEN

[This corrects the article DOI: 10.3389/fncel.2024.1347980.].

10.
Proc Natl Acad Sci U S A ; 121(19): e2322934121, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38701119

RESUMEN

EPH receptors (EPHs), the largest family of tyrosine kinases, phosphorylate downstream substrates upon binding of ephrin cell surface-associated ligands. In a large cohort of endometriotic lesions from individuals with endometriosis, we found that EPHA2 and EPHA4 expressions are increased in endometriotic lesions relative to normal eutopic endometrium. Because signaling through EPHs is associated with increased cell migration and invasion, we hypothesized that chemical inhibition of EPHA2/4 could have therapeutic value. We screened DNA-encoded chemical libraries (DECL) to rapidly identify EPHA2/4 kinase inhibitors. Hit compound, CDD-2693, exhibited picomolar/nanomolar kinase activity against EPHA2 (Ki: 4.0 nM) and EPHA4 (Ki: 0.81 nM). Kinome profiling revealed that CDD-2693 bound to most EPH family and SRC family kinases. Using NanoBRET target engagement assays, CDD-2693 had nanomolar activity versus EPHA2 (IC50: 461 nM) and EPHA4 (IC50: 40 nM) but was a micromolar inhibitor of SRC, YES, and FGR. Chemical optimization produced CDD-3167, having picomolar biochemical activity toward EPHA2 (Ki: 0.13 nM) and EPHA4 (Ki: 0.38 nM) with excellent cell-based potency EPHA2 (IC50: 8.0 nM) and EPHA4 (IC50: 2.3 nM). Moreover, CDD-3167 maintained superior off-target cellular selectivity. In 12Z endometriotic epithelial cells, CDD-2693 and CDD-3167 significantly decreased EFNA5 (ligand) induced phosphorylation of EPHA2/4, decreased 12Z cell viability, and decreased IL-1ß-mediated expression of prostaglandin synthase 2 (PTGS2). CDD-2693 and CDD-3167 decreased expansion of primary endometrial epithelial organoids from patients with endometriosis and decreased Ewing's sarcoma viability. Thus, using DECL, we identified potent pan-EPH inhibitors that show specificity and activity in cellular models of endometriosis and cancer.


Asunto(s)
Inhibidores de Proteínas Quinasas , Humanos , Femenino , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Endometriosis/tratamiento farmacológico , Endometriosis/metabolismo , Endometriosis/patología , ADN/metabolismo , Receptores de la Familia Eph/metabolismo , Receptores de la Familia Eph/antagonistas & inhibidores , Receptor EphA2/metabolismo , Receptor EphA2/antagonistas & inhibidores , Bibliotecas de Moléculas Pequeñas/farmacología , Bibliotecas de Moléculas Pequeñas/química , Movimiento Celular/efectos de los fármacos
11.
Nicotine Tob Res ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747193

RESUMEN

INTRODUCTION: High rates of tobacco use persist in the U.S. military, with 18.4% of service members smoking cigarettes in 2018. The Department of Defense's (DoD) 2017 policy required that tobacco retailers on military installations set tobacco product prices equal to the most common community price, including tax, but there is limited evidence confirming whether local retailers are adhering to this policy. We examined tobacco product pricing in tobacco retailers on- and off-post at the largest U.S. Army installation, Fort Liberty, and Cumberland County, North Carolina. METHODS: Between June-August 2021, we collected data on tobacco product availability, price, and promotions from retailers on Fort Liberty (n=14) and a random sample of off-post retailers within 10-miles of installation gates (n=52). We calculated the mode, mean, and median price of each product, plus the difference in these prices at on- and off-post retailers. We used Welch's t-test to test differences in mean prices between on- vs. off-post retailers. RESULTS: The mode, mean, and median prices of cigarette packs and cartons were lower on-post than off-post (e.g., $0.51-$0.55 cheaper for Marlboro cigarette packs on-post). However, the mode, mean, and median prices of smokeless tobacco products and little cigars were higher on-post than off-post (e.g., $0.82-$0.89 more costly for Swisher Sweets 2-packs on-post). CONCLUSION: Results highlight the need for continued enforcement to ensure compliance with the 2017 DoD policy. Comprehensive policy action to reduce tobacco price disparities on- and off-post is critical to reducing high rates of tobacco use among service members. IMPLICATIONS: Despite the implementation of the 2017 DoD pricing policy, some tobacco products remain cheaper at tobacco retailers on-post compared to off-post retailers. Our results highlight the need for greater routine surveillance to increase implementation of the policy-particularly for cigarettes-to reduce high rates of tobacco use among service members.

12.
Nicotine Tob Res ; 26(Supplement_2): S73-S81, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38817025

RESUMEN

BACKGROUND: The tobacco industry uses product descriptors to communicate reduced harm and increase appeal. This cross-sectional study assessed store-level racial, ethnic, and socioeconomic inequities in the distribution of retail tobacco product descriptors in a convenience sample of retailers in Washington, DC. METHODS: Young adults (n = 146) who did not currently use tobacco reported real-time store visits over 14 days. Trained data collectors took high-resolution photographs of all tobacco (including e-cigarette) marketing in each store (n = 96) participants visited. We coded text descriptors on tobacco product advertisements and displays into descriptor categories (eg, fruit, sweet, concept). We fit multilevel models to examine relationships between store neighborhood census tract-level racial, ethnic, and socioeconomic characteristics and tobacco product descriptors in stores. As a supplementary analysis, we used geospatial methods to model predicted patterns of descriptors at the census tract level. RESULTS: Stores located in census tracts with the highest versus lowest percentage of Black residents had a greater count of fruit, sweet or dessert, alcohol, and concept descriptors (p < .05), similar to findings from the geospatial approach. Adjusted models also indicated some inequities in stores in census tracts with higher percentages of Hispanic or Latino residents for fruit, alcohol, and concept descriptors; however, tract-level models showed opposite results for concept flavors. CONCLUSIONS: In this convenience sample, fruit, alcohol, sweet/dessert, and concept FTP descriptors were prevalent in stores in neighborhoods with more Black residents demonstrated through two analytic approaches. Surveillance using representative samples of tobacco retailers could improve the ability to track the extent of this inequity. IMPLICATIONS: We document inequities in the amount of fruit, sweet or dessert, alcohol, and concept flavor descriptors in stores across neighborhoods in Washington, DC. Federal, state, and local regulatory action is needed to reduce inequities in flavored tobacco product availability and marketing, including for concept flavors.


Asunto(s)
Características de la Residencia , Productos de Tabaco , Humanos , District of Columbia , Productos de Tabaco/estadística & datos numéricos , Productos de Tabaco/clasificación , Características de la Residencia/estadística & datos numéricos , Femenino , Estudios Transversales , Masculino , Adulto Joven , Adulto , Comercio/estadística & datos numéricos , Mercadotecnía/estadística & datos numéricos , Mercadotecnía/métodos , Factores Socioeconómicos , Adolescente , Publicidad/estadística & datos numéricos , Industria del Tabaco/estadística & datos numéricos
13.
Science ; 384(6698): 885-890, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38781365

RESUMEN

Men or mice with homozygous serine/threonine kinase 33 (STK33) mutations are sterile owing to defective sperm morphology and motility. To chemically evaluate STK33 for male contraception with STK33-specific inhibitors, we screened our multibillion-compound collection of DNA-encoded chemical libraries, uncovered potent STK33-specific inhibitors, determined the STK33 kinase domain structure bound with a truncated hit CDD-2211, and generated an optimized hit CDD-2807 that demonstrates nanomolar cellular potency (half-maximal inhibitory concentration = 9.2 nanomolar) and favorable metabolic stability. In mice, CDD-2807 exhibited no toxicity, efficiently crossed the blood-testis barrier, did not accumulate in brain, and induced a reversible contraceptive effect that phenocopied genetic STK33 perturbations without altering testis size. Thus, STK33 is a chemically validated, nonhormonal contraceptive target, and CDD-2807 is an effective tool compound.


Asunto(s)
Anticoncepción , Anticonceptivos Masculinos , Inhibidores de Proteínas Quinasas , Proteínas Serina-Treonina Quinasas , Bibliotecas de Moléculas Pequeñas , Animales , Humanos , Masculino , Ratones , Barrera Hematotesticular/metabolismo , Anticonceptivos Masculinos/química , Anticonceptivos Masculinos/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/química , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Testículo/efectos de los fármacos , Anticoncepción/métodos , Relación Estructura-Actividad
14.
Front Cell Neurosci ; 18: 1347980, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38584778

RESUMEN

Stroke, resulting in hypoxia and glucose deprivation, is a leading cause of death and disability worldwide. Presently, there are no treatments that reduce neuronal damage and preserve function aside from tissue plasminogen activator administration and rehabilitation therapy. Interestingly, Drosophila melanogaster, the common fruit fly, demonstrates robust hypoxic tolerance, characterized by minimal effects on survival and motor function following systemic hypoxia. Due to its organized brain, conserved neurotransmitter systems, and genetic similarity to humans and other mammals, uncovering the mechanisms of Drosophila's tolerance could be a promising approach for the development of new therapeutics. Interestingly, a key facet of hypoxic tolerance in Drosophila is organism-wide metabolic suppression, a response involving multiple genes and pathways. Specifically, studies have demonstrated that pathways associated with oxidative stress, insulin, hypoxia-inducible factors, NFκB, Wnt, Hippo, and Notch, all potentially contribute to Drosophila hypoxic tolerance. While manipulating the oxidative stress response and insulin signaling pathway has similar outcomes in Drosophila hypoxia and the mammalian middle cerebral artery occlusion (MCAO) model of ischemia, effects of Notch pathway manipulation differ between Drosophila and mammals. Additional research is warranted to further explore how other pathways implicated in hypoxic tolerance in Drosophila, such as NFκB, and Hippo, may be utilized to benefit mammalian response to ischemia. Together, these studies demonstrate that exploration of the hypoxic response in Drosophila may lead to new avenues of research for stroke treatment in humans.

15.
Soc Sci Med ; 349: 116900, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38669894

RESUMEN

INTRODUCTION: Little is known about uncontrolled vaping, defined as vaping more than the user prefers. We sought to understand e-cigarette users' experiences with uncontrolled vaping and how they restrain their vaping. METHODS: Participants were 24 US adult e-cigarette users recruited in 2021. We conducted semi-structured qualitative interviews about uncontrolled vaping and restraint strategies and analyzed findings based on behavioral categories described in the Process Model of Self-Control. RESULTS: While most participants (21 of 24) described experiences of uncontrolled vaping, some expressed ambivalence about how much they vaped. To restrain vaping, willpower was rarely used and was not perceived as effective. Distraction, deployment of attention away from the urge to vape, and reappraisal, thinking differently about vaping such as reminding oneself of health consequences, were common and helped some participants limit use in the moment of wanting to vape. Participants described using both situation selection, choosing to be in situations where e-cigarette use was less possible, and situation modification, modifying their circumstances to restrict opportunities to vape. DISCUSSION: Uncontrolled vaping is not yet a well-defined concept for many e-cigarette users. E-cigarette users employed proactive situational strategies that required planning ahead to restrain use and found these strategies more effective compared to reactive strategies. Tobacco control programs and interventions should consider leveraging restraint strategies that people who vape are naturally using and perceive to be effective.


Asunto(s)
Investigación Cualitativa , Vapeo , Humanos , Vapeo/psicología , Femenino , Adulto , Masculino , Persona de Mediana Edad , Sistemas Electrónicos de Liberación de Nicotina/estadística & datos numéricos , Autocontrol/psicología , Entrevistas como Asunto , Adulto Joven , Estados Unidos
16.
iScience ; 27(5): 109652, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38650988

RESUMEN

Dysregulation of the central amygdala is thought to underlie aberrant choice in alcohol use disorder, but the role of central amygdala neural activity during reward choice and consumption is unclear. We recorded central amygdala neurons in male rats as they consumed alcohol or sucrose. We observed activity changes at the time of reward approach, as well as lick-entrained activity during ongoing consumption of both rewards. In choice scenarios where rats could drink sucrose, alcohol, or quinine-adulterated alcohol with or without central amygdala optogenetic stimulation, rats drank more of stimulation-paired options when the two bottles contained identical options. Given a choice among different options, central amygdala stimulation usually enhanced consumption of stimulation-paired rewards. However, optogenetic stimulation during consumption of the less-preferred option, alcohol, was unable to enhance alcohol intake while sucrose was available. These findings indicate that the central amygdala contributes to refining motivated pursuit toward the preferred available option.

17.
Mol Cell ; 84(7): 1304-1320.e16, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38382526

RESUMEN

Cullin-RING ligases (CRLs) ubiquitylate specific substrates selected from other cellular proteins. Substrate discrimination and ubiquitin transferase activity were thought to be strictly separated. Substrates are recognized by substrate receptors, such as Fbox or BCbox proteins. Meanwhile, CRLs employ assorted ubiquitin-carrying enzymes (UCEs, which are a collection of E2 and ARIH-family E3s) specialized for either initial substrate ubiquitylation (priming) or forging poly-ubiquitin chains. We discovered specific human CRL-UCE pairings governing substrate priming. The results reveal pairing of CUL2-based CRLs and UBE2R-family UCEs in cells, essential for efficient PROTAC-induced neo-substrate degradation. Despite UBE2R2's intrinsic programming to catalyze poly-ubiquitylation, CUL2 employs this UCE for geometrically precise PROTAC-dependent ubiquitylation of a neo-substrate and for rapid priming of substrates recruited to diverse receptors. Cryo-EM structures illuminate how CUL2-based CRLs engage UBE2R2 to activate substrate ubiquitylation. Thus, pairing with a specific UCE overcomes E2 catalytic limitations to drive substrate ubiquitylation and targeted protein degradation.


Asunto(s)
Proteínas Cullin , Ubiquitina-Proteína Ligasas , Humanos , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas Cullin/genética , Proteínas Cullin/metabolismo , Ubiquitinación , Ubiquitina/metabolismo , Poliubiquitina/metabolismo , Proteínas Portadoras/metabolismo
18.
Protist ; 175(2): 126022, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38350283

RESUMEN

Karenia longicanalis, an athecate dinoflagellate, was first described during a bloom in Victoria Harbour (Hong Kong, China). This study confirms the presence of K. longicanalis as a bloom former in the eastern Pacific Ocean. Specimens were collected in March 2019 at three sampling stations in Acapulco Bay, Mexico. Water temperature, salinity, dissolved oxygen, and pH were measured in situ at the time of sample collection. Cell morphology was examined by optical and scanning electron microscopy. A molecular analysis based on the amplification of the large subunit (LSU) rDNA region revealed that the LSU sequences formed a monophyletic group with other GenBank sequences belonging to K. longicanalis. The resulting phylogeny demonstrates that Karenia is closely related to Asterodinium, Gertia, and Shimiella. The morphology of the specimens was consistent with previous descriptions.


Asunto(s)
Dinoflagelados , Océano Pacífico , Dinoflagelados/genética , China , Filogenia , ADN Ribosómico/genética
19.
Nicotine Tob Res ; 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38379278

RESUMEN

INTRODUCTION: This review investigates the impacts of banning the sale of menthol cigarettes at stores. METHODS: A systematic search of studies published in English up to November 2022 was conducted. The following databases were searched: PubMed/Medline, CINAHL, PsycINFO, Web of Science, and Embase, as well as a non-indexed journal. Studies evaluating either the impact of real-world or hypothesized menthol cigarette bans were included. Primary outcomes include tobacco use behaviors. Secondary outcomes include cigarette sales, retailer compliance, and the tobacco industry's response to a menthol ban. Data on tobacco use behavior after a menthol ban were pooled using random-effects models. Two pairs of reviewers independently extracted data and assessed study quality. RESULTS: Of the 964 articles that were identified during the initial search, 78 were included in the review and 16 were included in the meta-analysis. Cessation rates among menthol cigarette smokers were high after a menthol ban. Pooled results show that 24% (95% confidence interval [95% CI]: 20%, 28%) of menthol cigarette smokers quit smoking after a menthol ban, 50% (95% CI: 31%, 68%) switched to non-menthol cigarettes, 12% (95% CI: 3%, 20%) switched to other flavored tobacco products, and 24% (95% CI: 17%, 31%) continued smoking menthol cigarettes. Hypothesized quitting and switching rates were fairly close to real-world rates. Studies found the tobacco industry attempts to undermine menthol bans. National menthol bans appear more effective than local or state menthol bans. CONCLUSIONS: Menthol cigarette bans promote smoking cessation suggesting their potential to improve public health. IMPLICATIONS: Findings from this review suggest that menthol cigarette bans promote smoking cessation among menthol cigarette smokers and have the potential to improve public health.

20.
Nat Neurosci ; 27(2): 309-318, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38212586

RESUMEN

The nervous system uses fast- and slow-adapting sensory detectors in parallel to enable neuronal representations of external states and their temporal dynamics. It is unknown whether this dichotomy also applies to internal representations that have no direct correlation in the physical world. Here we find that two distinct dopamine (DA) neuron subtypes encode either a state or its rate-of-change. In mice performing a reward-seeking task, we found that the animal's behavioral state and rate-of-change were encoded by the sustained activity of DA neurons in medial ventral tegmental area (VTA) DA neurons and transient activity in lateral VTA DA neurons, respectively. The neural activity patterns of VTA DA cell bodies matched DA release patterns within anatomically defined mesoaccumbal pathways. Based on these results, we propose a model in which the DA system uses two parallel lines for proportional-differential encoding of a state variable and its temporal dynamics.


Asunto(s)
Dopamina , Neuronas Dopaminérgicas , Ratones , Animales , Dopamina/metabolismo , Neuronas Dopaminérgicas/fisiología , Recompensa , Área Tegmental Ventral/fisiología
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