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1.
Nat Immunol ; 20(10): 1372-1380, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31451789

RESUMO

In multicellular organisms, duplicated genes can diverge through tissue-specific gene expression patterns, as exemplified by highly regulated expression of RUNX transcription factor paralogs with apparent functional redundancy. Here we asked what cell-type-specific biologies might be supported by the selective expression of RUNX paralogs during Langerhans cell and inducible regulatory T cell differentiation. We uncovered functional nonequivalence between RUNX paralogs. Selective expression of native paralogs allowed integration of transcription factor activity with extrinsic signals, while non-native paralogs enforced differentiation even in the absence of exogenous inducers. DNA binding affinity was controlled by divergent amino acids within the otherwise highly conserved RUNT domain and evolutionary reconstruction suggested convergence of RUNT domain residues toward submaximal strength. Hence, the selective expression of gene duplicates in specialized cell types can synergize with the acquisition of functional differences to enable appropriate gene expression, lineage choice and differentiation in the mammalian immune system.


Assuntos
Subunidades alfa de Fatores de Ligação ao Core/genética , Sistema Imunitário/fisiologia , Células de Langerhans/fisiologia , Especificidade de Órgãos/genética , Linfócitos T Reguladores/fisiologia , Animais , Diferenciação Celular , Linhagem da Célula , Sequência Conservada , Evolução Molecular , Duplicação Gênica , Humanos , Mamíferos , Transdução de Sinais , Transcriptoma
2.
EMBO J ; 43(20): 4720-4751, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39256561

RESUMO

The fidelity of signal transduction requires the binding of regulatory molecules to their cognate targets. However, the crowded cell interior risks off-target interactions between proteins that are functionally unrelated. How such off-target interactions impact fitness is not generally known. Here, we use Saccharomyces cerevisiae to inducibly express tyrosine kinases. Because yeast lacks bona fide tyrosine kinases, the resulting tyrosine phosphorylation is biologically spurious. We engineered 44 yeast strains each expressing a tyrosine kinase, and quantitatively analysed their phosphoproteomes. This analysis resulted in ~30,000 phosphosites mapping to ~3500 proteins. The number of spurious pY sites generated correlates strongly with decreased growth, and we predict over 1000 pY events to be deleterious. However, we also find that many of the spurious pY sites have a negligible effect on fitness, possibly because of their low stoichiometry. This result is consistent with our evolutionary analyses demonstrating a lack of phosphotyrosine counter-selection in species with tyrosine kinases. Our results suggest that, alongside the risk for toxicity, the cell can tolerate a large degree of non-functional crosstalk as interaction networks evolve.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Fosforilação , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas Tirosina Quinases/metabolismo , Proteínas Tirosina Quinases/genética , Transdução de Sinais , Aptidão Genética , Fosfoproteínas/metabolismo , Fosfoproteínas/genética
3.
Annu Rev Physiol ; 86: 199-223, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345903

RESUMO

Obesity is epidemic and of great concern because of its comorbid and costly inflammatory-driven complications. Extensive investigations in mice have elucidated highly coordinated, well-balanced interactions between adipocytes and immune cells in adipose tissue that maintain normal systemic metabolism in the lean state, while in obesity, proinflammatory changes occur in nearly all adipose tissue immune cells. Many of these changes are instigated by adipocytes. However, less is known about obesity-induced adipose-tissue immune cell alterations in humans. Upon high-fat diet feeding, the adipocyte changes its well-known function as a metabolic cell to assume the role of an immune cell, orchestrating proinflammatory changes that escalate inflammation and progress during obesity. This transformation is particularly prominent in humans. In this review, we (a) highlight a leading and early role for adipocytes in promulgating inflammation, (b) discuss immune cell changes and the time course of these changes (comparing humans and mice when possible), and (c) note how reversing proinflammatory changes in most types of immune cells, including adipocytes, rescues adipose tissue from inflammation and obese mice from insulin resistance.


Assuntos
Tecido Adiposo , Macrófagos , Camundongos , Humanos , Animais , Adipócitos , Inflamação , Obesidade
4.
Circulation ; 150(7): 516-530, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39051104

RESUMO

BACKGROUND: Whether vigorous exercise increases risk of ventricular arrhythmias for individuals diagnosed and treated for congenital long QT syndrome (LQTS) remains unknown. METHODS: The National Institutes of Health-funded LIVE-LQTS study (Lifestyle and Exercise in the Long QT Syndrome) prospectively enrolled individuals 8 to 60 years of age with phenotypic and/or genotypic LQTS from 37 sites in 5 countries from May 2015 to February 2019. Participants (or parents) answered physical activity and clinical events surveys every 6 months for 3 years with follow-up completed in February 2022. Vigorous exercise was defined as ≥6 metabolic equivalents for >60 hours per year. A blinded Clinical Events Committee adjudicated the composite end point of sudden death, sudden cardiac arrest, ventricular arrhythmia treated by an implantable cardioverter defibrillator, and likely arrhythmic syncope. A National Death Index search ascertained vital status for those with incomplete follow-up. A noninferiority hypothesis (boundary of 1.5) between vigorous exercisers and others was tested with multivariable Cox regression analysis. RESULTS: Among the 1413 participants (13% <18 years of age, 35% 18-25 years of age, 67% female, 25% with implantable cardioverter defibrillators, 90% genotype positive, 49% with LQT1, 91% were treated with beta-blockers, left cardiac sympathetic denervation, and/or implantable cardioverter defibrillator), 52% participated in vigorous exercise (55% of these competitively). Thirty-seven individuals experienced the composite end point (including one sudden cardiac arrest and one sudden death in the nonvigorous group, one sudden cardiac arrest in the vigorous group) with overall event rates at 3 years of 2.6% in the vigorous and 2.7% in the nonvigorous exercise groups. The unadjusted hazard ratio for experience of events for the vigorous group compared with the nonvigorous group was 0.97 (90% CI, 0.57-1.67), with an adjusted hazard ratio of 1.17 (90% CI, 0.67-2.04). The upper 95% one-sided confidence level extended beyond the 1.5 boundary. Neither vigorous or nonvigorous exercise was found to be superior in any group or subgroup. CONCLUSIONS: Among individuals diagnosed with phenotypic and/or genotypic LQTS who were risk assessed and treated in experienced centers, LQTS-associated cardiac event rates were low and similar between those exercising vigorously and those not exercising vigorously. Consistent with the low event rate, CIs are wide, and noninferiority was not demonstrated. These data further inform shared decision-making discussions between patient and physician about exercise and competitive sports participation. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02549664.


Assuntos
Exercício Físico , Síndrome do QT Longo , Humanos , Síndrome do QT Longo/terapia , Síndrome do QT Longo/congênito , Síndrome do QT Longo/diagnóstico , Síndrome do QT Longo/fisiopatologia , Síndrome do QT Longo/mortalidade , Feminino , Masculino , Adolescente , Criança , Estudos Prospectivos , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Morte Súbita Cardíaca/prevenção & controle , Morte Súbita Cardíaca/epidemiologia , Fatores de Risco
5.
Mol Biol Evol ; 40(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37979156

RESUMO

Whole-genome duplication (WGD) followed by speciation allows us to examine the parallel evolution of ohnolog pairs. In the yeast family Saccharomycetaceae, HRR25 is a rare case of repeated ohnolog maintenance. This gene has reverted to a single copy in Saccharomyces cerevisiae where it is now essential, but has been maintained as pairs in at least 7 species post-WGD. In S. cerevisiae, HRR25 encodes the casein kinase 1δ/ε and plays a role in a variety of functions through its kinase activity and protein-protein interactions (PPIs). We hypothesized that the maintenance of duplicated HRR25 ohnologs could be a result of repeated subfunctionalization. We tested this hypothesis through a functional complementation assay in S. cerevisiae, testing all pairwise combinations of 25 orthologs (including 7 ohnolog pairs). Contrary to our expectations, we observed no cases of pair-dependent complementation, which would have supported the subfunctionalization hypothesis. Instead, most post-WGD species have one ohnolog that failed to complement, suggesting their nonfunctionalization or neofunctionalization. The ohnologs incapable of complementation have undergone more rapid protein evolution, lost most PPIs that were observed for their functional counterparts and singletons from post-WGD and non-WGD species, and have nonconserved cellular localization, consistent with their ongoing loss of function. The analysis in Naumovozyma castellii shows that the noncomplementing ohnolog is expressed at a lower level and has become nonessential. Taken together, our results indicate that HRR25 orthologs are undergoing gradual nonfunctionalization.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomycetales , Saccharomyces cerevisiae/genética , Duplicação Gênica , Genoma Fúngico , Evolução Molecular , Saccharomycetales/genética , Proteínas de Saccharomyces cerevisiae/genética , Caseína Quinase I/genética
6.
Glob Chang Biol ; 30(2): e17178, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38332577

RESUMO

Climate change and anthropogenic stressors are redistributing species and altering community composition globally. Protected areas (PAs) may not sufficiently protect populations of species undergoing distributional shifts, necessitating that we evaluate existing PAs and identify areas for future protection to conserve biodiversity across regional and temporal scales. Coastal waterbirds are important indicators of marine ecosystem health, representing mobile, long-lived, higher trophic-level consumers. Using a 20-year citizen science dataset (1999-2019) with a before-after control-intervention sampling framework for habitat protection, we applied dynamic occupancy models to assess winter occupancy trends along the Pacific coast of Canada. Specifically, we sought to understand potential drivers of regional declines, spatial commonalities among guilds, and changes in habitat use before and after PA designation, as well as between PAs and non-PAs. Occupancy trends varied regionally, with greater declines in the south compared to the north. Regional differences underlined potential range shifts, particularly for species with traits linked to temperature tolerance, movement, and high productivity foraging, as cold-tolerant, migratory benthivores and piscivores wintered farther north relative to 20 years ago or retreated to cold-water fjords. While 21 of 57 (36.8%) species responded positively to PA designation (before-after), greater occupancy declines tended to occur in PAs established pre-1999 relative to non-PAs (control-intervention). Since PAs are currently concentrated in the south, negative associations were most apparent for species retreating northward, but existing PAs may have a stabilizing or transitory effect on southern wintering species shifting into the region from farther south. We emphasize that conservation strategies must balance persistence of current communities with preserving the climate-adapted biodiversity of tomorrow by accounting for community-level effects of species moving into and out of existing PAs. Incorporating range shifts into PA planning by predicting distributional changes will allow conservation practitioners to identify priority habitats, such as cold-water refugia, for persistent wildlife communities.


Le changement climatique et les facteurs de stress anthropiques redistribuent les espèces et modifient la composition des communautés à l'échelle mondiale. Les zones protégées (ZP) ne protègent peut-être pas suffisamment les populations d'espèces qui subissent des changements de répartition, ce qui nous oblige à évaluer les ZP existantes et à identifier les zones à protéger à l'avenir pour conserver la biodiversité à l'échelle régionale et temporelle. Les oiseaux côtiers sont des indicateurs importants de la santé des écosystèmes marins, car ils représentent des consommateurs mobiles, ont une longue durée de vie et représente le niveau trophique supérieur. En utilisant un ensemble de données de science participative sur 20 ans (1999-2019) avec un échantillonnage avant-après contrôle-intervention (AACI) pour la protection de l'habitat, nous avons appliqué des modèles d'occupation dynamiques pour évaluer les tendances de l'occupation hivernale le long de la côte pacifique du Canada. Plus précisément, nous avons cherché à comprendre les moteurs potentiels des déclins régionaux, les points communs spatiaux entre les guildes et les changements dans l'utilisation de l'habitat avant et après la désignation de le ZP, ainsi qu'entre les ZP et les non-ZP. Les tendances en matière d'occupation varient d'une région à l'autre, avec des déclins plus importants dans le sud que dans le nord. Les différences régionales soulignent les déplacements potentiels de l'aire de répartition, en particulier pour les espèces dont les caractéristiques sont liées à la tolérance à la température, aux déplacements et à la recherche de nourriture à rendement élevé, car les benthivores et les piscivores migrateurs tolérants au froid ont hiverné plus au nord qu'il y a 20 ans ou se sont retirés dans les fjords aux eaux froides. Alors que 21 des 57 (36,8 %) espèces ont réagi positivement à la désignation des aires protégées (avant-après), les baisses d'occupation ont eu tendance à être plus importantes dans les aires protégées créées avant 1999 que dans les aires non protégées (contrôle-intervention). Comme les aires protégées sont actuellement concentrées dans le sud, les associations négatives étaient plus évidentes pour les espèces qui se retirent vers le nord, mais les aires protégées existantes peuvent avoir un effet stabilisateur ou transitoire sur les espèces hivernant dans le sud qui se déplacent dans la région à partir d'une région plus au sud. Nous soulignons que les stratégies de conservation doivent trouver un équilibre entre la persistance des communautés actuelles et la préservation de la biodiversité adaptée au climat de demain, en tenant compte des effets au niveau des communautés des espèces qui entrent dans les aires protégées existantes ou qui en sortent. L'intégration des changements d'aire de répartition dans la planification des aires protégées en prédisant les changements de distribution permettra aux praticiens de la conservation d'identifier les habitats prioritaires, tels que les refuges d'eau froide, pour les communautés d'espèces sauvages persistantes.


Assuntos
Aves , Ecossistema , Animais , Conservação dos Recursos Naturais , Biodiversidade , Mudança Climática , Água
7.
Curr Opin Gastroenterol ; 40(5): 422-430, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38967932

RESUMO

PURPOSE OF REVIEW: This review examines current research on healthcare disparities in pancreatitis, identifies knowledge gaps, and proposes strategies to develop targeted multilevel interventions to address inequities in pancreatitis care. RECENT FINDINGS: Current literature has identified patient, disease, and healthcare-level factors contributing to disparities in risk factors and health outcomes of pancreatitis. Moreover, social structures, economic systems, social vulnerability, and policy significantly influence the pancreatitis care continuum. SUMMARY: Understanding the root causes of health inequities is critical to developing effective approaches for the prevention, early detection, and management of pancreatitis.


Assuntos
Disparidades em Assistência à Saúde , Pancreatite , Humanos , Pancreatite/terapia , Fatores de Risco , Fatores Socioeconômicos
8.
Inorg Chem ; 63(22): 10103-10107, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38780238

RESUMO

Zinc norcorrole was prepared as its pyridine complex (ZnNc·pyridine) by metalation of freebase norcorrole. The ZnNc·pyridine complex is distinctly bowl-shaped, as demonstrated by both X-ray crystallography and nuclear magnetic resonance (NMR) spectroscopy. NMR spectroscopy showed characteristic ring current deshielding effects, with different magnitudes on either face of the bowl-shaped complex. Exchanging the pyridine ligand with the bidentate ligand DABCO results in the formation of a stable (ZnNc)2·DABCO sandwich complex, which was also characterized by crystallography and NMR spectroscopy. The NMR resonances of the axial ligands in all of the complexes demonstrate that the paratropic ring current in zinc norcorrole is approximately 40 nA/T, which is comparable in magnitude to the diatropic ring current in porphyrin. Analysis of the ligand-exchange processes on addition of DABCO to ZnNc·pyridine showed that ZnNc coordinates to axial nitrogen-containing ligands with approximately 1000-fold higher binding constants than analogous zinc porphyrins.

9.
J Xray Sci Technol ; 32(3): 611-622, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38607727

RESUMO

BACKGROUND: Accurate diagnosis and subsequent delineated treatment planning require the experience of clinicians in the handling of their case numbers. However, applying deep learning in image processing is useful in creating tools that promise faster high-quality diagnoses, but the accuracy and precision of 3-D image processing from 2-D data may be limited by factors such as superposition of organs, distortion and magnification, and detection of new pathologies. The purpose of this research is to use radiomics and deep learning to develop a tool for lung cancer diagnosis. METHODS: This study applies radiomics and deep learning in the diagnosis of lung cancer to help clinicians accurately analyze the images and thereby provide the appropriate treatment planning. 86 patients were recruited from Bach Mai Hospital, and 1012 patients were collected from an open-source database. First, deep learning has been applied in the process of segmentation by U-NET and cancer classification via the use of the DenseNet model. Second, the radiomics were applied for measuring and calculating diameter, surface area, and volume. Finally, the hardware also was designed by connecting between Arduino Nano and MFRC522 module for reading data from the tag. In addition, the displayed interface was created on a web platform using Python through Streamlit. RESULTS: The applied segmentation model yielded a validation loss of 0.498, a train loss of 0.27, a cancer classification validation loss of 0.78, and a training accuracy of 0.98. The outcomes of the diagnostic capabilities of lung cancer (recognition and classification of lung cancer from chest CT scans) were quite successful. CONCLUSIONS: The model provided means for storing and updating patients' data directly on the interface which allowed the results to be readily available for the health care providers. The developed system will improve clinical communication and information exchange. Moreover, it can manage efforts by generating correlated and coherent summaries of cancer diagnoses.


Assuntos
Aprendizado Profundo , Neoplasias Pulmonares , Tomografia Computadorizada por Raios X , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Pulmão/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos
10.
J Perianesth Nurs ; 39(1): 10-15, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37855761

RESUMO

Adverse surgical events cause negative patient health outcomes and harm that can often overshadow the safe and effective patient care provided daily by nurses as members of interprofessional healthcare teams. Near misses occur far more frequently than adverse events and are less visible to nurse leaders because patient harm is avoided due to chance, prevention, or mitigation. However, near misses have comparable root causes to adverse events and exhibit the same underlying patterns of failure. Reviewing near misses provides nurses with learning opportunities to identify patient care weaknesses and build appropriate solutions to enhance care. As the operating room is one of the most complex work settings in healthcare, identifying potential weaknesses or sources for errors is vital to reduce healthcare-associated risks for patients and staff. The purpose of this manuscript is to educate, inform, and stimulate critical thinking by discussing perioperative near miss case studies and the underlying factors that lead to errors. Our authors discuss 15 near miss case studies occurring across the perioperative patient experience of care and discuss barriers to near miss reporting. Nurse leaders can use our case studies to stimulate discussion among perioperative and perianesthesia nurses in their hospitals to inform comprehensive risk reduction programs.


Assuntos
Near Miss , Gestão de Riscos , Humanos , Segurança do Paciente , Salas Cirúrgicas , Acidentes , Erros Médicos/prevenção & controle
11.
J Stroke Cerebrovasc Dis ; 32(9): 107278, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37549479

RESUMO

OBJECTIVE: In-hospital stroke cases occur during hospitalization for another diagnosis and reflect a clinically distinct cohort from community-onset stroke. The objective was to validate the diagnostic accuracy of in-hospital stroke identification in stroke audit data at a large teaching hospital. METHODS: A retrospective clinical validation of in-hospital stroke diagnoses from two linked data sources was completed for a 2-year period from January 1st 2020 to December 31st 2021. The linked data sources include the Hospital Inpatient Enquiry system which assigns coded stroke diagnoses at discharge and/or the local stroke audit coordinators who work clinically in stroke teams and input additional specific clinical data. Diagnostic sensitivity, specificity and the level of agreement using an unweighted Cohen's Kappa were calculated. RESULTS: There were 597 strokes admitted during the 2-year period. The median age was 72 years and 55% occurred in males. In total, 88 cases of in-hospital stroke were clinically validated yielding an in-hospital stroke rate of 15%. The clinical audit coordinator identified in-hospital stroke with higher sensitivity (86%; 95% CI 77%-93%) whereas the coding process was more specific at 96% (95% CI 85% to 99%). Levels of agreement with the clinically validated gold standard sample were moderate for the audit coordinator and coding process with κ = 0.57 and K = 0.42 respectively. When both data sources were combined the level of agreement was substantial (κ = 0.65; p < .000). CONCLUSIONS: Clinical validation studies are required to reinforce data quality within stroke registers. Combining clinical and administrative data sources improves diagnostic accuracy for in-hospital stroke identification.


Assuntos
Acidente Vascular Cerebral , Masculino , Humanos , Idoso , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/terapia , Hospitais , Hospitalização , Alta do Paciente
12.
Plant J ; 107(1): 287-302, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33866624

RESUMO

Mass spectrometry is the predominant analytical tool used in the field of plant lipidomics. However, there are many challenges associated with the mass spectrometric detection and identification of lipids because of the highly complex nature of plant lipids. Studies into lipid biosynthetic pathways, gene functions in lipid metabolism, lipid changes during plant growth and development, and the holistic examination of the role of plant lipids in environmental stress responses are often hindered. Here, we leveraged a robust pipeline that we previously established to extract and analyze lipid profiles of different tissues and developmental stages from the model plant Arabidopsis thaliana. We analyzed seven tissues at several different developmental stages and identified more than 200 lipids from each tissue analyzed. The data were used to create a web-accessible in silico lipid map that has been integrated into an electronic Fluorescent Pictograph (eFP) browser. This in silico library of Arabidopsis lipids allows the visualization and exploration of the distribution and changes of lipid levels across selected developmental stages. Furthermore, it provides information on the characteristic fragments of lipids and adducts observed in the mass spectrometer and their retention times, which can be used for lipid identification. The Arabidopsis tissue lipid map can be accessed at http://bar.utoronto.ca/efp_arabidopsis_lipid/cgi-bin/efpWeb.cgi.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Lipidômica/métodos , Lipídeos/análise , Visualização de Dados , Metabolismo Energético , Glucuronídeos/análise , Glucuronídeos/metabolismo , Metabolismo dos Lipídeos , Fotossíntese , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Espectrometria de Massas em Tandem/métodos , Triglicerídeos/metabolismo
13.
Clin Gastroenterol Hepatol ; 20(9): 2005-2013, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34571258

RESUMO

BACKGROUND & AIMS: Chronic pancreatitis (CP) is associated with osteopathy (osteoporosis or osteopenia). However, existing literature is mostly limited to retrospective or administrative studies that have not clearly defined the prevalence and risk factors. Our aim was to identify patient- and disease-related associations with osteopathy in a prospective cohort study of CP. METHODS: We studied 282 subjects with definitive CP enrolled in the PROCEED study who had a baseline dual-energy X-ray absorptiometry (DXA) scan. Osteopenia and osteoporosis were defined using the lowest T-scores. Clinical data were collected using standardized case report forms. Comparisons were performed with a multivariate logistic regression model with forward selection to identify risk factors for osteopathy. RESULTS: The majority of subjects had osteopathy on DXA scan (56.0%; 17.0% osteoporosis; 39.0% osteopenia). Subjects with osteopathy had a higher prevalence of traumatic (40.0% vs 26.4%; P = .02) and spontaneous fractures (3.9% vs 0; P = .04). On multivariate analysis, older age (odds ratio [OR], 1.29 per 5 years; 95% confidence interval [CI], 1.15-1.45), female sex (OR, 3.08; 95% CI, 1.75-5.43), white race (OR, 2.68; 95% CI, 1.20-6.01), and underweight body mass index category (OR, 7.40; 95% CI, 1.56-34.99) were associated with higher probability of osteopathy. There were no significant associations between osteopathy and other patient and disease-related features of CP. CONCLUSION: In the largest study of patients with CP who underwent DXA screening, the majority had osteopathy. There are overlapping risk factors with osteopathy in the general population, but the high prevalence in men and younger women supports the need for future investigations into the mechanisms of bone loss in CP. CLINICALTRIALS: gov number, NCT03099850.


Assuntos
Doenças Ósseas Metabólicas , Osteoporose , Pancreatite Crônica , Densidade Óssea , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco
14.
PLoS Biol ; 17(6): e3000341, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31233486

RESUMO

Protein kinases catalyse the phosphorylation of target proteins, controlling most cellular processes. The specificity of serine/threonine kinases is partly determined by interactions with a few residues near the phospho-acceptor residue, forming the so-called kinase-substrate motif. Kinases have been extensively duplicated throughout evolution, but little is known about when in time new target motifs have arisen. Here, we show that sequence variation occurring early in the evolution of kinases is dominated by changes in specificity-determining residues. We then analysed kinase specificity models, based on known target sites, observing that specificity has remained mostly unchanged for recent kinase duplications. Finally, analysis of phosphorylation data from a taxonomically broad set of 48 eukaryotic species indicates that most phosphorylation motifs are broadly distributed in eukaryotes but are not present in prokaryotes. Overall, our results suggest that the set of eukaryotes kinase motifs present today was acquired around the time of the eukaryotic last common ancestor and that early expansions of the protein kinase fold rapidly explored the space of possible target motifs.


Assuntos
Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Especificidade por Substrato/genética , Motivos de Aminoácidos/genética , Sequência de Aminoácidos/genética , Animais , Evolução Biológica , Domínio Catalítico , Eucariotos/enzimologia , Evolução Molecular , Humanos , Fosforilação , Células Procarióticas/enzimologia , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases/genética , Especificidade por Substrato/fisiologia
15.
Phys Chem Chem Phys ; 24(19): 11486-11490, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35506979

RESUMO

Electronic delocalization is essential to the properties of π-conjugated molecules. We introduce the inter-fragment delocalization index (IFDI) as an easy-to-use computational method for quantifying the electronic delocalization in π-conjugated oligomers and molecular wire models. We show that the IFDI is related to the torsion barriers of π-conjugated dimers, and to the single-molecule conductance of several π-conjugated fragments. The IFDI is a useful screening technique for comparing different π-conjugated subunits as components in organic electronics, since it can quantify the influence of substitution position, structure, and (anti)aromaticity on delocalization.

16.
Angew Chem Int Ed Engl ; 61(36): e202201231, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-35818688

RESUMO

A recent Research Article in this journal by Matito and co-workers claimed that none of the oxidation states of a butadiyne-linked six-porphyrin nanoring exhibit global aromaticity or antiaromaticity. Here we show that this conclusion is incorrect. Experimental data from NMR spectroscopy for a whole family of nanorings provide strong evidence for global ring currents. The NMR data reveal these ring currents directly, without needing analysis by density functional theory (DFT). Furthermore, DFT calculations reproduce the experimental results when a suitable functional is used.

17.
J Immunol ; 202(8): 2451-2459, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30850480

RESUMO

Macrophages, B cells, and adipocytes are among the adipose tissue (AT) APCs that differentiate and activate naive CD4+ T cells. Mice with adipocyte loss of MHC class II (MHC II) are more insulin sensitive. Because macrophages are professional APCs, mice with genetic myeloid MHC II depletion (myeloid MHC II knockout [mMHCII-/-]) were created and metabolically characterized. FITC+ glucan-coated particles (glucan-encapsulated small interfering RNA [siRNA] particles [GeRPs]) were also used to target MHC II knockout specifically in AT macrophages (ATMs). Mice with total body mMHCII-/- were generated by crossing LyzMCre with H2Ab1 floxed mice. For specific ATM depletion of H2Ab1, GeRPs containing H2Ab1 siRNA were administered to high-fat diet-fed C57BL/6 mice. Unexpectedly, mMHCII-/- mice had loss of both macrophage and adipocyte H2Ab1, one of only two Ag-presenting arms; thus, neither cell could present Ag and activate CD4+ T cells. This inability led to a reduction in AT immunosuppressive regulatory T cells, increased AT CD8+ T cells, and no improvement in systemic metabolism. Thus, with combined systemic myeloid and adipocyte MHC II loss, the impact of ATM-specific alterations in APC activity could not be delineated. Therefore, GeRPs containing H2Ab1 siRNA were administered to specifically reduce ATM H2Ab1 which, in contrast, revealed improved glucose tolerance. In conclusion, loss of either ATM or adipocyte APC function, but not both, improves systemic glucose metabolism because of maintenance of AT regulatory T cells.


Assuntos
Adipócitos/imunologia , Tecido Adiposo/imunologia , Apresentação de Antígeno , Glucose/imunologia , Macrófagos/imunologia , Adipócitos/citologia , Tecido Adiposo/citologia , Animais , Apresentação de Antígeno/genética , Apresentação de Antígeno/imunologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Glucose/genética , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Macrófagos/citologia , Camundongos , Camundongos Knockout
18.
Pacing Clin Electrophysiol ; 44(10): 1671-1674, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34351650

RESUMO

BACKGROUND: A benefit of automatically transmitting or "wireless" CIEDs (W-CIED) is the prompt detection of device malfunction and arrhythmias. We hypothesized that the use of W-CIEDs would improve the efficiency of remote monitoring by decreasing unnecessary CIED remote transmissions because of the automatic detection of abnormalities. OBJECTIVE: To compare the frequency of patient-initiated transmissions in patients with W-CIEDs versus non-wireless CIEDs (NW-CIED) at a single pediatric and congenital heart center. METHODS: Retrospective cohort study of patients with W-CIEDs followed over a 2-year period compared to a similar cohort of patients with NW-CIED. All CIED remote transmissions during were reviewed for indication and outcome. RESULTS: The W-CIED cohort had 87 patients; mean age 20 ± 13 years; NW-CIED cohort had 220 patients; mean age 22 ± (13) years. The mean number of symptomatic patient-initiated transmissions per patient was 0.93 ± 2.65 in the W-CIED cohort versus 0.39 ± 0.64 in the NW-CIED cohort (p ≤ .001). The mean number of asymptomatic patient-initiated transmission sent per patient in the W-CIED cohort was 1.86 ± 2.59 versus 0.81 ± 1.41 in the NW-CIED cohort (p ≤ .0001). Type of device, age, and presence of congenital heart disease were not significantly associated with the incidence of patient-initiated remote monitoring transmissions. CONCLUSIONS: The frequency of patient-initiated transmission was higher in the W-CIED cohort, contradictory to the study hypothesis. This may reflect a lack of patient understanding of the benefit or functionality of W-CIEDs and may be mitigated by education to both providers and patients.


Assuntos
Desfibriladores Implantáveis , Cardiopatias Congênitas/terapia , Monitorização Fisiológica/métodos , Marca-Passo Artificial , Tecnologia sem Fio , Feminino , Humanos , Masculino , Michigan , Estudos Retrospectivos , Adulto Jovem
19.
Surg Endosc ; 35(6): 3131-3138, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32572626

RESUMO

BACKGROUND: Adipose tissue (AT) inflammation is linked to the development of type 2 diabetes (T2DM) and atherosclerosis in murine models of obesity. Reduced AT regulatory T cells (Tregs), which are anti-inflammatory immune cells, play an important part in this pathogenesis, and we have shown that AT-Tregs are inversely correlated to increasing body-mass-index. The purpose of this study was to evaluate the association between AT-Treg abundance and comorbidity status in patients undergoing bariatric surgery (BS). METHODS: Visceral (intra-abdominal) AT was harvested at that time of primary BS (n = 80) and collagenase digested. AT-Treg abundance (CD4+/CD25+/FOXP3+) was characterized using flow cytometry from the AT stromal vascular fraction. The median AT-Treg abundance (3.03%) was utilized to define high (High-Tregs, n = 39) and low AT-Treg (low-Tregs, n = 38) abundance within this cohort. These two groups were compared in terms of baseline demographic data, preoperative obesity-related comorbidities, glycemic parameters, including insulin resistance (HOMA-IR). RESULTS: Age, excess body weight, and sex were not different between groups. Prevalence of hypertension, hyperlipidemia, or T2DM preoperatively were not different between groups. Compared to High-Tregs, patients with low-Tregs were more likely to have insulin-dependent type 2 diabetes (12.5% vs 2.9%, p = 0.04). Within patients with T2DM, low-Treg patients had higher plasma insulin levels compared to high-Tregs (31.8 (28.4-56.5) vs 15.5 (10.1-23.1), p = 0.04) and trended towards higher insulin resistance (HOMA-IR) (9.0 (5.3-18.3) vs 3.5 (2.2-7.7), p = 0.08). Within those diagnosed with hyperlipidemia, preoperative statin use was higher in Low-Treg patients compared to the control cohort (91% vs 50%, p = 0.056). Low-Treg patients with hypertension were more likely to need 2 + anti-hypertensive agents preoperatively compared to their counterparts (71% vs 44%, p = 0.058). CONCLUSION: Within bariatric candidates, lower visceral AT-Treg abundance was associated with increased baseline medication requirements for type 2 diabetes, hypertension, and hyperlipidemia. This suggests that reduced AT-Tregs may be associated with higher obesity-related comorbidity severity.


Assuntos
Cirurgia Bariátrica , Diabetes Mellitus Tipo 2 , Animais , Comorbidade , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Gordura Intra-Abdominal , Camundongos , Linfócitos T Reguladores
20.
Adv Exp Med Biol ; 1278: 125-139, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33523447

RESUMO

Obesity dramatically increases the risk of numerous conditions, including type 2 diabetes mellitus and other components of the metabolic syndrome. Pro-inflammatory changes that occur in adipose tissue are critical to the pathogenesis of these obesity-induced complications. Adipose tissue is one of the body's largest endocrine organs, and the cells that comprise the adipose tissue immunoenvironment secrete multiple factors (including adipokines and cytokines) that impact systemic metabolism. In particular, immunosuppressive regulatory T cells (Tregs) decline in obesity, partly in response to its complex interaction with adipocytes, and this decline contributes to disruption of the typical homeostasis observed in lean adipose tissue. Although the regulation of Treg differentiation, function, and enrichment is incompletely understood, factors including various cell-surface co-stimulatory molecules, certain lipid species, and cytokines such as PPARγ, adiponectin, and leptin are important mediators. It is also clear that there may be depot-specific differences in Tregs, rendering adipose tissue Tregs distinct from lymphoid or circulating Tregs, with implications on maintenance and functionality. While most of these findings are derived from studies in murine models, comparatively little is known about the human adipose tissue Treg signature, which requires further investigation.


Assuntos
Diabetes Mellitus Tipo 2 , Linfócitos T Reguladores , Adipocinas , Tecido Adiposo , Animais , Humanos , Inflamação , Camundongos , Obesidade
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