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1.
Am J Pathol ; 194(2): 209-224, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38029921

RESUMEN

The mechanisms by which maternal obesity increases the susceptibility to steatotic liver disease in offspring are incompletely understood. Models using different maternal obesogenic diets (MODEs) display phenotypic variability, likely reflecting the influence of timing and diet composition. This study compared three maternal obesogenic diets using standardized exposure times to identify differences in offspring disease progression. This study found that the severity of hepatic inflammation and fibrosis in the offspring depends on the composition of the maternal obesogenic diet. Offspring cecal microbiome composition was shifted in all MODE groups relative to control. Decreased α-diversity in some MODE offspring with shifts in abundance of multiple genera were suggestive of delayed maturation of the microbiome. The weaning reaction typically characterized by a spike in intestinal expression of Tnfa and Ifng was attenuated in MODE offspring in an early microbiome-dependent manner using cross-fostering. Cross-fostering also switched the severity of disease progression in offspring dependent on the diet of the fostering dam. These results identify maternal diet composition and timing of exposure as modifiers in mediating transmissible changes in the microbiome. These changes in the early microbiome alter a critical window during weaning that drives susceptibility to progressive liver disease in the offspring.


Asunto(s)
Hígado Graso , Microbiota , Efectos Tardíos de la Exposición Prenatal , Femenino , Humanos , Embarazo , Destete , Obesidad/complicaciones , Obesidad/metabolismo , Dieta Alta en Grasa/efectos adversos , Efectos Tardíos de la Exposición Prenatal/metabolismo , Dieta/efectos adversos , Hígado Graso/metabolismo , Progresión de la Enfermedad , Hígado/metabolismo
2.
Proc Natl Acad Sci U S A ; 119(11): e2115480119, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35254891

RESUMEN

SignificanceComputational protein design promises to advance applications in medicine and biotechnology by creating proteins with many new and useful functions. However, new functions require the design of specific and often irregular atom-level geometries, which remains a major challenge. Here, we develop computational methods that design and predict local protein geometries with greater accuracy than existing methods. Then, as a proof of concept, we leverage these methods to design new protein conformations in the enzyme ketosteroid isomerase that change the protein's preference for a key functional residue. Our computational methods are openly accessible and can be applied to the design of other intricate geometries customized for new user-defined protein functions.


Asunto(s)
Aminoácidos/química , Diseño Asistido por Computadora , Ingeniería de Proteínas/métodos , Proteínas/química , Robótica , Algoritmos , Biología Computacional/métodos , Isomerasas/química , Modelos Moleculares , Conformación Proteica , Proteínas/genética , Reproducibilidad de los Resultados , Relación Estructura-Actividad
3.
Artículo en Inglés | MEDLINE | ID: mdl-39236288

RESUMEN

Nicotine exposure in the context of smoking or vaping worsens airway function. Although commonly thought to exert effects through the peripheral nervous system, we previously showed airway smooth muscle (ASM) expresses nicotinic acetylcholine receptors (nAChRs), particularly alpha7 subtype (α7nAChR) with functional effects on contractility and metabolism. However, the mechanisms of nAChR regulation and downstream effects in ASM are not fully understood. Using human ASM cells from non-asthmatics vs. mild-moderate asthmatics, we tested the hypothesis that nAChR-specific ER chaperones RIC-3 and TMEM35 promote cell surface localization of α7nAChR with downstream influence on its functionality: effects exacerbated by inflammation. We found that mild-moderate asthma and exposure to pro-inflammatory cytokines relevant to asthma promote chaperone and α7nAChR expression in ASM. Downstream, ER stress was linked to nicotine/α7nAChR signaling, where RIC-3 and TMEM35 regulate nicotine-induced ER stress, Ca2+ regulation and ASM cell proliferation. Overall, our data highlights the importance α7nAChR chaperones in mediating and modulating nicotine effects in ASM towards airway contractility and remodeling.

4.
J Am Chem Soc ; 146(14): 10001-10013, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38532610

RESUMEN

The ability to create efficient artificial enzymes for any chemical reaction is of great interest. Here, we describe a computational design method for increasing the catalytic efficiency of de novo enzymes by several orders of magnitude without relying on directed evolution and high-throughput screening. Using structural ensembles generated from dynamics-based refinement against X-ray diffraction data collected from crystals of Kemp eliminases HG3 (kcat/KM 125 M-1 s-1) and KE70 (kcat/KM 57 M-1 s-1), we design from each enzyme ≤10 sequences predicted to catalyze this reaction more efficiently. The most active designs display kcat/KM values improved by 100-250-fold, comparable to mutants obtained after screening thousands of variants in multiple rounds of directed evolution. Crystal structures show excellent agreement with computational models, with catalytic contacts present as designed and transition-state root-mean-square deviations of ≤0.65 Å. Our work shows how ensemble-based design can generate efficient artificial enzymes by exploiting the true conformational ensemble to design improved active sites.


Asunto(s)
Enzimas , Cristalografía por Rayos X , Difracción de Rayos X , Dominio Catalítico , Catálisis , Enzimas/metabolismo
5.
Am J Physiol Lung Cell Mol Physiol ; 326(2): L149-L163, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38084408

RESUMEN

With continued smoking of tobacco products and expanded use of nicotine delivery devices worldwide, understanding the impact of smoking and vaping on respiratory health remains a major global unmet need. Although multiple studies have shown a strong association between smoking and asthma, there is a relative paucity of mechanistic understanding of how elements in cigarette smoke impact the airway. Recognizing that nicotine is a major component in both smoking and vaping products, it is critical to understand the mechanisms by which nicotine impacts airways and promotes lung diseases such as asthma. There is now increasing evidence that α7 nicotinic acetylcholine receptors (α7nAChRs) are critical players in nicotine effects on airways, but the mechanisms by which α7nAChR influences different airway cell types have not been widely explored. In this review, we highlight and integrate the current state of knowledge regarding nicotine and α7nAChR in the context of asthma and identify potential approaches to alleviate the impact of smoking and vaping on the lungs.


Asunto(s)
Asma , Receptores Nicotínicos , Trastornos Respiratorios , Humanos , Receptores Nicotínicos/metabolismo , Nicotina/efectos adversos , Nicotina/metabolismo , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo , Pulmón/metabolismo , Asma/metabolismo , Trastornos Respiratorios/metabolismo , Productos de Tabaco
6.
Artículo en Inglés | MEDLINE | ID: mdl-39189800

RESUMEN

Bronchial airways and lung parenchyma undergo both static and dynamic stretch in response to normal breathing but also in the context of insults such as mechanical ventilation (MV) or in diseases such as asthma and COPD which lead to airway remodeling involving increased extracellular matrix (ECM) production. Here, the role of fibroblasts is critical, but the relationship between stretch and fibroblast induced ECM remodeling under these conditions is not well-explored. Piezo (PZ) channels play a role in mechanotransduction in many cell and organ systems, but their role in mechanical stretch-induced airway remodeling is not known. To explore this, we exposed human lung fibroblasts to 10% static stretch on a background of 5% oscillations for 48 hours, with no static stretch considered controls. Collagen I, Fibronectin, α-SMA, and Piezo 1 (PZ1) expression were determined in the presence or absence of Yoda1 (PZ1 agonist) or GsMTx4 (PZ1 inhibitor). Collagen I, Fibronectin, and α-SMA expression was increased by stretch and Yoda1 while pretreatment with GsMTx4 or knockdown of PZ1 by siRNA blunted this effect. Acute stretch in the presence and absence of Yoda1 demonstrated activation of ERK pathway but not Smad. Measurement of [Ca2+] i responses to histamine showed significantly greater responses following stretch: effects that were blunted by knockdown of PZ1.Our findings identify an essential role for PZ1 in mechanical stretch-induced production of ECM mediated by ERK phosphorylation and Ca2+ influx in lung fibroblasts. Targeting PZ channels in fibroblasts may constitute a novel approach to ameliorate airway remodeling by decreasing ECM deposition.

7.
Am J Physiol Lung Cell Mol Physiol ; 327(2): L150-L159, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38771147

RESUMEN

Alteration in the normal mechanical forces of breathing can contribute to changes in contractility and remodeling characteristic of airway diseases, but the mechanisms that mediate these effects in airway cells are still under investigation. Airway smooth muscle (ASM) cells contribute to both contractility and extracellular matrix (ECM) remodeling. In this study, we explored ASM mechanisms activated by mechanical stretch, focusing on mechanosensitive piezo channels and the key Ca2+ regulatory protein stromal interaction molecule 1 (STIM1). Expression of Ca2+ regulatory proteins, including STIM1, Orai1, and caveolin-1, mechanosensitive ion channels Piezo-1 and Piezo-2, and NLRP3 inflammasomes were upregulated by 10% static stretch superimposed on 5% cyclic stretch. These effects were blunted by STIM1 siRNA. Histamine-induced [Ca2+]i responses and inflammasome activation were similarly blunted by STIM1 knockdown. These data show that the effects of mechanical stretch in human ASM cells are mediated through STIM1, which activates multiple pathways, including Piezo channels and the inflammasome, leading to potential downstream changes in contractility and ECM remodeling.NEW & NOTEWORTHY Mechanical forces on the airway can contribute to altered contractility and remodeling in airway diseases, but the mechanisms are not clearly understood. Using human airway smooth muscle cells exposed to cyclic forces with static stretch to mimic breathing and static pressure, we found that the effects of stretch are mediated through STIM1, resulting in the activation of multiple pathways, including Piezo channels and the inflammasome, with potential downstream influences on contractility and remodeling.


Asunto(s)
Miocitos del Músculo Liso , Molécula de Interacción Estromal 1 , Humanos , Molécula de Interacción Estromal 1/metabolismo , Molécula de Interacción Estromal 1/genética , Miocitos del Músculo Liso/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/genética , Inflamasomas/metabolismo , Estrés Mecánico , Mecanotransducción Celular , Músculo Liso/metabolismo , Canales Iónicos/metabolismo , Caveolina 1/metabolismo , Caveolina 1/genética , Transducción de Señal , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Calcio/metabolismo , Células Cultivadas , Contracción Muscular/fisiología , Remodelación de las Vías Aéreas (Respiratorias)/fisiología , Proteína ORAI1/metabolismo , Proteína ORAI1/genética
8.
Small ; 20(21): e2310577, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38279633

RESUMEN

Bridging functionalities in periodic mesoporous organosilicas (PMOs) enable new functionalities for a wide range of applications. Bridge cleavage is frequently observed during anneals required to form porous structures, yet the mechanism of these bridge cleavages has not been completely resolved. Here, these chemical transformations and their kinetic pathways on sub-millisecond timescales induced by laser heating are revealed. By varying anneal times and temperatures, the transformation dynamics of bridge cleavage and structural transformations and their activation energies are determined. The structural relaxation time for individual reactions and their effective local heating time are determined and compared, and the results directly demonstrate the manipulation of different molecules through kinetic control of the sequence of reactions. By isolating and understanding the earliest stage of structural transformations, this study identifies the kinetic principles for new synthesis and post-processing routes to control individual molecules and reactions in PMOs and other material systems with multi-functionalities.

9.
Epilepsia ; 65(5): 1415-1427, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38407370

RESUMEN

OBJECTIVE: Understanding factors driving variation in status epilepticus outcomes would be critical to improve care. We evaluated the degree to which patient and hospital characteristics explained hospital-to-hospital variability in intubation and postacute outcomes. METHODS: This was a retrospective cohort study of Medicare beneficiaries admitted with status epilepticus between 2009 and 2019. Outcomes included intubation, discharge to a facility, and 30- and 90-day readmissions and mortality. Multilevel models calculated percent variation in each outcome due to hospital-to-hospital differences. RESULTS: We included 29 150 beneficiaries. The median age was 68 years (interquartile range [IQR] = 57-78), and 18 084 (62%) were eligible for Medicare due to disability. The median (IQR) percentages of each outcome across hospitals were: 30-day mortality 25% (0%-38%), any 30-day readmission 14% (0%-25%), 30-day status epilepticus readmission 0% (0%-3%), 30-day facility stay 40% (25%-53%), and intubation 46% (20%-61%). However, after accounting for many hospitals with small sample size, hospital-to-hospital differences accounted for 2%-6% of variation in all unadjusted outcomes, and approximately 1%-5% (maximally 8% for 30-day readmission for status epilepticus) after adjusting for patient, hospitalization, and/or hospital characteristics. Although many characteristics significantly predicted outcomes, the largest effect size was cardiac arrest predicting death (odds ratio = 10.1, 95% confidence interval = 8.8-11.7), whereas hospital characteristics (e.g., staffing, accreditation, volume, setting, services) all had lesser effects. SIGNIFICANCE: Hospital-to-hospital variation explained little variation in studied outcomes. Rather, certain patient characteristics (e.g., cardiac arrest) had greater effects. Interventions to improve outcomes after status epilepticus may be better focused on individual or prehospital factors, rather than at the inpatient systems level.


Asunto(s)
Hospitales , Readmisión del Paciente , Estado Epiléptico , Humanos , Estado Epiléptico/terapia , Estado Epiléptico/mortalidad , Anciano , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Readmisión del Paciente/estadística & datos numéricos , Estados Unidos/epidemiología , Hospitales/estadística & datos numéricos , Medicare/estadística & datos numéricos , Estudios de Cohortes , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Anciano de 80 o más Años , Resultado del Tratamiento
10.
Catheter Cardiovasc Interv ; 103(3): 490-498, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38329195

RESUMEN

BACKGROUND: Transcatheter aortic valve replacement (TAVR) has changed the landscape of aortic stenosis (AS) management. AIM: To describe and evaluate geographic variation in AS treatment and outcomes among a sample of Medicare beneficiaries. METHODS: A retrospective analysis of administrative claims data was conducted on a 20% sample of Medicare fee-for-service beneficiaries aged 65 and older with a diagnosis of AS (2015-2018). Estimates of demographic, comorbidity, and healthcare resources were obtained from Medicare claims and the Dartmouth Atlas of Health Care at the hospital referral region (HRR), which represents regional tertiary medical care markets. Linear regression was used to explain HRR-level variation in rates of surgical aortic valve replacement (SAVR) and TAVR, and 1-year mortality and readmission rates. RESULTS: A total of 740,899 beneficiaries with AS were identified with a median prevalence of AS of 39.9 per 1000 Medicare beneficiary years. The average HRR-level rate of SAVR was 26.3 procedures per 1000 beneficiary years and the rate of TAVR was 20.3 procedures per 1000 beneficiary years. HRR-level comorbidities and number of TAVR centers were associated with a lower SAVR rate. Demographics and comorbidities explained most of the variation in HRR-level 1-year mortality (15.2% and 18.8%) and hospitalization rates (20.5% and 16.9%), but over half of the variation remained unexplained. CONCLUSION: Wide regional variation in the treatment and outcomes of AS was observed but were largely unexplained by patient factors and healthcare utilization. Understanding the determinants of AS treatment and outcomes can inform population health efforts for these patients.


Asunto(s)
Estenosis de la Válvula Aórtica , Implantación de Prótesis de Válvulas Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Anciano , Estados Unidos/epidemiología , Medicare , Estudios Retrospectivos , Resultado del Tratamiento , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/etiología , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Constricción Patológica , Factores de Riesgo
11.
Nucleic Acids Res ; 50(15): 8974-8985, 2022 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-35947747

RESUMEN

Information processing functions are essential for organisms to perceive and react to their complex environment, and for humans to analyze and rationalize them. While our brain is extraordinary at processing complex information, winner-take-all, as a type of biased competition is one of the simplest models of lateral inhibition and competition among biological neurons. It has been implemented as DNA-based neural networks, for example, to mimic pattern recognition. However, the utility of DNA-based computation in information processing for real biotechnological applications remains to be demonstrated. In this paper, a biased competition method for nonlinear manipulation and analysis of mixtures of DNA sequences was developed. Unlike conventional biological experiments, selected species were not directly subjected to analysis. Instead, parallel computation among a myriad of different DNA sequences was carried out to reduce the information entropy. The method could be used for various oligonucleotide-encoded libraries, as we have demonstrated its application in decoding and data analysis for selection experiments with DNA-encoded chemical libraries against protein targets.


Asunto(s)
Redes Neurales de la Computación , Neuronas , Humanos , Neuronas/fisiología , Computadores Moleculares , ADN/genética , ADN/química , Encéfalo
12.
Nucleic Acids Res ; 50(3): 1449-1464, 2022 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-35061900

RESUMEN

DNA methylation modulates telomere function. In Arabidopsis thaliana, telomeric regions have a bimodal chromatin organization with unmethylated telomeres and methylated subtelomeres. To gain insight into this organization we have generated TAIR10-Tel, a modified version of the Arabidopsis reference genome with additional sequences at most chromosome ends. TAIR10-Tel has allowed us to analyse DNA methylation at nucleotide resolution level in telomeric regions. We have analysed the wild-type strain and mutants that encode inactive versions of all currently known relevant methyltransferases involved in cytosine methylation. These analyses have revealed that subtelomeric DNA methylation extends 1 to 2 kbp from Interstitial Telomeric Sequences (ITSs) that abut or are very near to telomeres. However, DNA methylation drops at the telomeric side of the telomere-subtelomere boundaries and disappears at the inner part of telomeres. We present a comprehensive and integrative model for subtelomeric DNA methylation that should help to decipher the mechanisms that govern the epigenetic regulation of telomeres. This model involves a complex network of interactions between methyltransferases and subtelomeric DNA sequences.


Asunto(s)
Arabidopsis , Metilación de ADN , Arabidopsis/genética , Epigénesis Genética , Metiltransferasas/genética , Telómero/genética
13.
Proc Natl Acad Sci U S A ; 118(10)2021 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-33649198

RESUMEN

Persistent methicillin-resistant Staphylococcus aureus (MRSA) bacteremia is life threatening and occurs in up to 30% of MRSA bacteremia cases despite appropriate antimicrobial therapy. Isolates of MRSA that cause antibiotic-persistent methicillin-resistant S. aureus bacteremia (APMB) typically have in vitro antibiotic susceptibilities equivalent to those causing antibiotic-resolving methicillin-resistant S. aureus bacteremia (ARMB). Thus, persistence reflects host-pathogen interactions occurring uniquely in context of antibiotic therapy in vivo. However, host factors and mechanisms involved in APMB remain unclear. We compared DNA methylomes in circulating immune cells from patients experiencing APMB vs. ARMB. Overall, methylation signatures diverged in the distinct patient cohorts. Differentially methylated sites intensified proximate to transcription factor binding sites, primarily in enhancer regions. In APMB patients, significant hypomethylation was observed in binding sites for CCAAT enhancer binding protein-ß (C/EBPß) and signal transducer/activator of transcription 1 (STAT1). In contrast, hypomethylation in ARMB patients localized to glucocorticoid receptor and histone acetyltransferase p300 binding sites. These distinct methylation signatures were enriched in neutrophils and achieved a mean area under the curve of 0.85 when used to predict APMB using a classification model. These findings validated by targeted bisulfite sequencing (TBS-seq) differentiate epigenotypes in patients experiencing APMB vs. ARMB and suggest a risk stratification strategy for antibiotic persistence in patients treated for MRSA bacteremia.


Asunto(s)
Bacteriemia/metabolismo , Metilación de ADN , Staphylococcus aureus Resistente a Meticilina/metabolismo , Elementos de Respuesta , Infecciones Estafilocócicas/metabolismo , Antibacterianos/administración & dosificación , Bacteriemia/tratamiento farmacológico , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factor de Transcripción STAT1/metabolismo , Infecciones Estafilocócicas/tratamiento farmacológico , Factores de Transcripción p300-CBP/metabolismo
14.
Sensors (Basel) ; 24(17)2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39275399

RESUMEN

Oxytetracycline (OTC) is a widely employed antibiotic in veterinary treatment and in the prevention of infections, potentially leaving residues in animal-derived food products, such as milk, that are consumed by humans. Given the detrimental effects of prolonged human exposure to antibiotics, it has become imperative to develop precise and sensitive methods for monitoring the presence of OTC in food. Herein, we describe the development and results of a preliminary label-free electrochemical aptasensor with antifouling properties designed to detect OTC in milk samples. The sensor was realized by modifying a gold screen-printed electrode with α-lipoic acid-NHS and an amine-terminated aptamer. Different electrochemical techniques were used to study the steps of the fabrication process and to quantify OTC in the presence of the Fe(CN)64-/Fe(CN)63- redox couple The detectable range of concentrations satisfy the maximum residue limits set by the European Union, with an limit of detection (LOD) of 14 ng/mL in phosphate buffer (BP) and 10 ng/mL in the milk matrix, and a dynamic range of up to 500 ng/mL This study is a steppingstone towards the implementation of a sensitive monitoring method for OTC in dairy products.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Técnicas Electroquímicas , Leche , Oxitetraciclina , Oxitetraciclina/análisis , Oxitetraciclina/química , Técnicas Electroquímicas/métodos , Técnicas Biosensibles/métodos , Leche/química , Aptámeros de Nucleótidos/química , Animales , Límite de Detección , Oro/química , Electrodos , Antibacterianos/análisis , Antibacterianos/química , Humanos
15.
Environ Monit Assess ; 196(4): 369, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38489113

RESUMEN

Protected areas are typically managed as a network of sites exposed to varying anthropogenic conditions. Managing these networks benefits from monitoring of conditions across sites to help prioritize coordinated efforts. Monitoring marine vessel activity and related underwater radiated noise impacts across a network of protected areas, like the U.S. National Marine Sanctuary system, helps managers ensure the quality of habitats used by a wide range of marine species. Here, we use underwater acoustic detections of vessels to quantify different characteristics of vessel noise at 25 locations within eight marine sanctuaries including the Hawaiian Archipelago and the U.S. east and west coasts. Vessel noise metrics, including temporal presence and sound levels, were paired with Automatic Identification System (AIS) vessel tracking data to derive a suite of robust vessel noise indicators for use across the network of marine protected areas. Network-wide comparisons revealed a spectrum of vessel noise conditions that closely matched AIS vessel traffic composition. Shifts in vessel noise were correlated with the decrease in vessel activity early in the COVID-19 pandemic, and vessel speed reduction management initiatives. Improving our understanding of vessel noise conditions in these protected areas can help direct opportunities for reducing vessel noise, such as establishing and maintaining noise-free periods, enhancing port efficiency, engaging with regional and international vessel quieting initiatives, and leveraging co-benefits of management actions for reducing ocean noise.


Asunto(s)
Pandemias , Navíos , Humanos , Monitoreo del Ambiente , Ruido , Acústica , Ecosistema
16.
Am J Physiol Lung Cell Mol Physiol ; 325(6): L803-L818, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37933473

RESUMEN

Exposure to cigarette smoke and e-cigarettes, with nicotine as the active constituent, contributes to increased health risks associated with asthma. Nicotine exerts its functional activity via nicotinic acetylcholine receptors (nAChRs), and the alpha7 subtype (α7nAChR) has recently been shown to adversely affect airway dynamics. The mechanisms of α7nAChR action in airways, particularly in the context of airway smooth muscle (ASM), a key cell type in asthma, are still under investigation. Mitochondria have garnered increasing interest for their role in regulating airway tone and adaptations to cellular stress. Here mitochondrial dynamics such as fusion versus fission, and mitochondrial Ca2+ ([Ca2+]m), play an important role in mitochondrial homeostasis. There is currently no information on effects and mechanisms by which nicotine regulates mitochondrial structure and function in ASM in the context of asthma. We hypothesized that nicotine disrupts mitochondrial morphology, fission-fusion balance, and [Ca2+]m regulation, with altered mitochondrial respiration and bioenergetics in the context of asthmatic ASM. Using human ASM (hASM) cells from nonasthmatics, asthmatics, and smokers, we examined the effects of nicotine on mitochondrial dynamics and [Ca2+]m. Fluorescence [Ca2+]m imaging of hASM cells with rhod-2 showed robust responses to 10 µM nicotine, particularly in asthmatics and smokers. In both asthmatics and smokers, nicotine increased the expression of fission proteins while decreasing fusion proteins. Seahorse analysis showed blunted oxidative phosphorylation parameters in response to nicotine in these groups. α7nAChR siRNA blunted nicotine effects, rescuing [Ca2+]m, changes in mitochondrial structural proteins, and mitochondrial dysfunction. These data highlight mitochondria as a target of nicotine effects on ASM, where mitochondrial disruption and impaired buffering could permit downstream effects of nicotine in the context of asthma.NEW & NOTEWORTHY Asthma is a major healthcare burden, which is further exacerbated by smoking. Recognizing the smoking risk of asthma, understanding the effects of nicotine on asthmatic airways becomes critical. Surprisingly, the mechanisms of nicotine action, even in normal and especially asthmatic airways, are understudied. Accordingly, the goal of this research is to investigate how nicotine influences asthmatic airways in terms of mitochondrial structure and function, via the a7nAChR.


Asunto(s)
Asma , Sistemas Electrónicos de Liberación de Nicotina , Humanos , Nicotina/farmacología , Nicotina/metabolismo , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo , Miocitos del Músculo Liso/metabolismo , Asma/metabolismo , Mitocondrias/metabolismo
17.
Mol Biol Evol ; 39(4)2022 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-35388432

RESUMEN

The repeated evolution of the same traits in distantly related groups (convergent evolution) raises a key question in evolutionary biology: do the same genes underpin convergent phenotypes? Here, we explore one such trait, viviparity (live birth), which, qualitative studies suggest, may indeed have evolved via genetic convergence. There are >150 independent origins of live birth in vertebrates, providing a uniquely powerful system to test the mechanisms underpinning convergence in morphology, physiology, and/or gene recruitment during pregnancy. We compared transcriptomic data from eight vertebrates (lizards, mammals, sharks) that gestate embryos within the uterus. Since many previous studies detected qualitative similarities in gene use during independent origins of pregnancy, we expected to find significant overlap in gene use in viviparous taxa. However, we found no more overlap in uterine gene expression associated with viviparity than we would expect by chance alone. Each viviparous lineage exhibits the same core set of uterine physiological functions. Yet, contrary to prevailing assumptions about this trait, we find that none of the same genes are differentially expressed in all viviparous lineages, or even in all viviparous amniote lineages. Therefore, across distantly related vertebrates, different genes have been recruited to support the morphological and physiological changes required for successful pregnancy. We conclude that redundancies in gene function have enabled the repeated evolution of viviparity through recruitment of different genes from genomic "toolboxes", which are uniquely constrained by the ancestries of each lineage.


Asunto(s)
Lagartos , Viviparidad de Animales no Mamíferos , Animales , Evolución Biológica , Femenino , Genómica , Lagartos/genética , Mamíferos/fisiología , Placenta , Embarazo , Viviparidad de Animales no Mamíferos/genética
18.
Ann Surg ; 277(2): 223-227, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34387197

RESUMEN

OBJECTIVE: Our objective was to evaluate changes in elective surgical volume in Michigan while an executive order (EO) was in place curtailing elective surgery during the COVID-19 pandemic. SUMMARY BACKGROUND DATA: Many state governors enacted EOs curtailing elective surgery to protect scare resources and generate hospital capacity for patients with COVID-19. Little is known of the effectiveness of an EO on achieving a sustained reduction in elective surgery. METHODS: This retrospective cohort study of data from a statewide claims-based registry in Michigan includes claims from the largest private payer in the state for a representative set of elective operations on adult patients from February 2 through August 1, 2020. We reported trends in surgical volume over the period the EO was in place. Estimated backlogs in elective surgery were calculated using case counts from the same period in 2019. RESULTS: Hospitals achieved a 91.7% reduction in case volume before the EO was introduced. By the time the order was rescinded, hospitals were already performing elective surgery at 60.1% of pre-pandemic case rates. We estimate that a backlog of 6419 operations was created while the EO was in effect. Had hospitals ceased elective surgery during this period, an additional 18% of patients would have experienced a delay in surgical care. CONCLUSIONS: Both the introduction and removal of Michigan's EO lagged behind the observed ramp-down and ramp-up in elective surgical volume. These data suggest that EOs may not effectively modulate surgical care and could also contribute to unnecessary delays in surgical care.


Asunto(s)
COVID-19 , Adulto , Humanos , COVID-19/epidemiología , Pandemias , Michigan/epidemiología , Estudios Retrospectivos , Procedimientos Quirúrgicos Electivos
19.
J Urol ; 210(1): 128-135, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37114615

RESUMEN

PURPOSE: The ROCKS (Reducing Operative Complications from Kidney Stones) program in MUSIC (Michigan Urological Surgery Improvement Collaborative) was created to optimize ureteroscopy outcomes. Through data collection, distribution of reports, patient education, and standardization of medication, post-ureteroscopy emergency department visits in Michigan have declined. It is unclear whether this is because of statewide quality efforts or due to national trends. We therefore sought to understand emergency department visit rates in Michigan compared to a national data set. MATERIALS AND METHODS: We compared the MUSIC ROCKS clinical registry in Michigan against a national cohort, Optum's de-identified Clinformatics Data Mart, from 2016-2021 (excluding Michigan). We identified patients who underwent ureteroscopy and the proportion who had a postoperative emergency department visit within 30 days. Emergency department rates were modeled over time, adjusting for age, gender, comorbidity, and ureteral stenting. RESULTS: We identified 24,688 patients in MUSIC ROCKS and 99,340 in the Clinformatics Data Mart database who underwent ureteroscopy. The risk-adjusted emergency department visit rate in MUSIC ROCKS significantly declined over the study period (10.5% in 2016 to 6.9% in 2021, P < 0.001) while the mean emergency department visit rate in the Clinformatics Data Mart cohort was 9.9% and did not change over time (9.6% in 2016 to 10% in 2021). Comparing emergency department visits between the cohorts, the MUSIC ROCKS rate significantly declined relative to the Clinformatics Data Mart (P < 0.001) over the study period. CONCLUSIONS: Postoperative emergency department visit rates in Michigan have declined significantly after ureteroscopy since the establishment of MUSIC ROCKS. This decline outpaced national rates, providing evidence that systematic quality initiatives can improve urological care.


Asunto(s)
Cálculos Renales , Uréter , Cálculos Ureterales , Cálculos Urinarios , Humanos , Ureteroscopía , Cálculos Renales/cirugía , Servicio de Urgencia en Hospital , Cálculos Ureterales/cirugía , Resultado del Tratamiento
20.
J Card Fail ; 29(4): 531-535, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36283645

RESUMEN

OBJECTIVE: Health literacy is associated with heart failure (HF) care and outcomes. Online resources offer important educational materials for patients seeking access to heart transplantation but tend to be complex and potentially ineffective for non-English speakers and those with low reading levels. The purpose of this study was to evaluate both the readability of patient-level information posted on United States heart transplant center websites and the availability of non-English resources. METHODS AND RESULTS: We performed a review of patient-facing information on websites of U.S. heart transplant centers identified through the United Network for Organ Sharing in August 2022. Written English text was extracted and assessed for readability by using the Fry Graph Readability score. Websites were additionally evaluated for non-English language text and translator tools. Standard ANOVA analysis was used to compare readability levels across transplant regions. The median Fry readability level to understand a piece of text for all regions was 15, which is equivalent to a college-junior reading level (range: 7-17, 7th grade to postgraduate level). There was no statistical difference in median Fry readability levels among regions (P = 0.16). Of the 139 eligible heart transplant center websites, only 56.1% (78/139) had non-English resources available for patients. Regions 5 (75% [15/20]) and 6 (75% [3/4]) had the highest percentage of non-English resources, and region 2 had the lowest (38% [6/16]). CONCLUSIONS: Heart transplant center online resources are inadequate, and many do not provide translations of the English language. Additional work is needed to standardize heart-transplant patient information for a diverse U.S.


Asunto(s)
Alfabetización en Salud , Insuficiencia Cardíaca , Trasplante de Corazón , Humanos , Estados Unidos , Comprensión , Insuficiencia Cardíaca/cirugía , Lenguaje , Internet
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