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1.
Nature ; 632(8027): 1145-1154, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38862028

RESUMO

Spaceflight induces molecular, cellular and physiological shifts in astronauts and poses myriad biomedical challenges to the human body, which are becoming increasingly relevant as more humans venture into space1-6. Yet current frameworks for aerospace medicine are nascent and lag far behind advancements in precision medicine on Earth, underscoring the need for rapid development of space medicine databases, tools and protocols. Here we present the Space Omics and Medical Atlas (SOMA), an integrated data and sample repository for clinical, cellular and multi-omic research profiles from a diverse range of missions, including the NASA Twins Study7, JAXA CFE study8,9, SpaceX Inspiration4 crew10-12, Axiom and Polaris. The SOMA resource represents a more than tenfold increase in publicly available human space omics data, with matched samples available from the Cornell Aerospace Medicine Biobank. The Atlas includes extensive molecular and physiological profiles encompassing genomics, epigenomics, transcriptomics, proteomics, metabolomics and microbiome datasets, which reveal some consistent features across missions, including cytokine shifts, telomere elongation and gene expression changes, as well as mission-specific molecular responses and links to orthologous, tissue-specific mouse datasets. Leveraging the datasets, tools and resources in SOMA can help to accelerate precision aerospace medicine, bringing needed health monitoring, risk mitigation and countermeasure data for upcoming lunar, Mars and exploration-class missions.


Assuntos
Astronautas , Bancos de Espécimes Biológicos , Genômica , Voo Espacial , Humanos , Medicina Aeroespacial , Metabolômica , Proteômica , Epigenômica , Medicina de Precisão , Masculino , Internacionalidade , Microbiota/genética , Atlas como Assunto , Animais
2.
Nature ; 619(7970): 487-490, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37468588

RESUMO

Several long-period radio transients have recently been discovered, with strongly polarized coherent radio pulses appearing on timescales between tens to thousands of seconds1,2. In some cases, the radio pulses have been interpreted as coming from rotating neutron stars with extremely strong magnetic fields, known as magnetars; the origin of other, occasionally periodic and less-well-sampled radio transients is still debated3. Coherent periodic radio emission is usually explained by rotating dipolar magnetic fields and pair-production mechanisms, but such models do not easily predict radio emission from such slowly rotating neutron stars and maintain it for extended times. On the other hand, highly magnetic isolated white dwarfs would be expected to have long spin periodicities, but periodic coherent radio emission has not yet been directly detected from these sources. Here we report observations of a long-period (21 min) radio transient, which we have labelled GPM J1839-10. The pulses vary in brightness by two orders of magnitude, last between 30 and 300 s and have quasiperiodic substructure. The observations prompted a search of radio archives and we found that the source has been repeating since at least 1988. The archival data enabled constraint of the period derivative to <3.6 × 10-13 s s-1, which is at the very limit of any classical theoretical model that predicts dipolar radio emission from an isolated neutron star.

3.
Proc Natl Acad Sci U S A ; 120(7): e2206797120, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36757889

RESUMO

Genetic studies have identified ≥240 loci associated with the risk of type 2 diabetes (T2D), yet most of these loci lie in non-coding regions, masking the underlying molecular mechanisms. Recent studies investigating mRNA expression in human pancreatic islets have yielded important insights into the molecular drivers of normal islet function and T2D pathophysiology. However, similar studies investigating microRNA (miRNA) expression remain limited. Here, we present data from 63 individuals, the largest sequencing-based analysis of miRNA expression in human islets to date. We characterized the genetic regulation of miRNA expression by decomposing the expression of highly heritable miRNAs into cis- and trans-acting genetic components and mapping cis-acting loci associated with miRNA expression [miRNA-expression quantitative trait loci (eQTLs)]. We found i) 84 heritable miRNAs, primarily regulated by trans-acting genetic effects, and ii) 5 miRNA-eQTLs. We also used several different strategies to identify T2D-associated miRNAs. First, we colocalized miRNA-eQTLs with genetic loci associated with T2D and multiple glycemic traits, identifying one miRNA, miR-1908, that shares genetic signals for blood glucose and glycated hemoglobin (HbA1c). Next, we intersected miRNA seed regions and predicted target sites with credible set SNPs associated with T2D and glycemic traits and found 32 miRNAs that may have altered binding and function due to disrupted seed regions. Finally, we performed differential expression analysis and identified 14 miRNAs associated with T2D status-including miR-187-3p, miR-21-5p, miR-668, and miR-199b-5p-and 4 miRNAs associated with a polygenic score for HbA1c levels-miR-216a, miR-25, miR-30a-3p, and miR-30a-5p.


Assuntos
Diabetes Mellitus Tipo 2 , Ilhotas Pancreáticas , MicroRNAs , Humanos , MicroRNAs/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Hemoglobinas Glicadas , Ilhotas Pancreáticas/metabolismo , Locos de Características Quantitativas/genética
4.
Proc Natl Acad Sci U S A ; 120(9): e2216430120, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36802441

RESUMO

Monitoring the extracellular environment for danger signals is a critical aspect of cellular survival. However, the danger signals released by dying bacteria and the mechanisms bacteria use for threat assessment remain largely unexplored. Here, we show that lysis of Pseudomonas aeruginosa cells releases polyamines that are subsequently taken up by surviving cells via a mechanism that relies on Gac/Rsm signaling. While intracellular polyamines spike in surviving cells, the duration of this spike varies according to the infection status of the cell. In bacteriophage-infected cells, intracellular polyamines are maintained at high levels, which inhibits replication of the bacteriophage genome. Many bacteriophages package linear DNA genomes and linear DNA is sufficient to trigger intracellular polyamine accumulation, suggesting that linear DNA is sensed as a second danger signal. Collectively, these results demonstrate how polyamines released by dying cells together with linear DNA allow P. aeruginosa to make threat assessments of cellular injury.


Assuntos
Bacteriófagos , Poliaminas , Bacteriófagos/genética , Bactérias , Pseudomonas aeruginosa , DNA
5.
Mol Microbiol ; 121(1): 116-128, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038061

RESUMO

Quorum sensing, a bacterial signaling system that coordinates group behaviors as a function of cell density, plays an important role in regulating viral (phage) defense mechanisms in bacteria. The opportunistic pathogen Pseudomonas aeruginosa is a model system for the study of quorum sensing. P. aeruginosa is also frequently infected by Pf prophages that integrate into the host chromosome. Upon induction, Pf phages suppress host quorum sensing systems; however, the physiological relevance and mechanism of suppression are unknown. Here, we identify the Pf phage protein PfsE as an inhibitor of Pseudomonas Quinolone Signal (PQS) quorum sensing. PfsE binds to the host protein PqsA, which is essential for the biosynthesis of the PQS signaling molecule. Inhibition of PqsA increases the replication efficiency of Pf virions when infecting a new host and when the Pf prophage switches from lysogenic replication to active virion replication. In addition to inhibiting PQS signaling, our prior work demonstrates that PfsE also binds to PilC and inhibits type IV pili extension, protecting P. aeruginosa from infection by type IV pili-dependent phages. Overall, this work suggests that the simultaneous inhibition of PQS signaling and type IV pili by PfsE may be a viral strategy to suppress host defenses to promote Pf replication while at the same time protecting the susceptible host from competing phages.


Assuntos
Bacteriófagos , Pseudomonas aeruginosa , Quinolonas , Pseudomonas aeruginosa/genética , Bacteriófagos/metabolismo , Transdução de Sinais , Percepção de Quorum/genética , Replicação Viral , Proteínas de Bactérias/metabolismo
6.
PLoS Pathog ; 19(2): e1010925, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36800381

RESUMO

The opportunistic pathogen Pseudomonas aeruginosa PAO1 is infected by the filamentous bacteriophage Pf4. Pf4 virions promote biofilm formation, protect bacteria from antibiotics, and modulate animal immune responses in ways that promote infection. Furthermore, strains cured of their Pf4 infection (ΔPf4) are less virulent in animal models of infection. Consistently, we find that strain ΔPf4 is less virulent in a Caenorhabditis elegans nematode infection model. However, our data indicate that PQS quorum sensing is activated and production of the pigment pyocyanin, a potent virulence factor, is enhanced in strain ΔPf4. The reduced virulence of ΔPf4 despite high levels of pyocyanin production may be explained by our finding that C. elegans mutants unable to sense bacterial pigments through the aryl hydrocarbon receptor are more susceptible to ΔPf4 infection compared to wild-type C. elegans. Collectively, our data support a model where suppression of quorum-regulated virulence factors by Pf4 allows P. aeruginosa to evade detection by innate host immune responses.


Assuntos
Inovirus , Fagos de Pseudomonas , Animais , Pseudomonas aeruginosa , Caenorhabditis elegans/microbiologia , Piocianina , Percepção de Quorum , Fatores de Virulência , Biofilmes , Antibacterianos/farmacologia , Proteínas de Bactérias
7.
J Bacteriol ; 206(5): e0040223, 2024 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-38687034

RESUMO

Pseudomonas aeruginosa is an opportunistic bacterial pathogen that commonly causes medical hardware, wound, and respiratory infections. Temperate filamentous Pf phages that infect P. aeruginosa impact numerous virulence phenotypes. Most work on Pf phages has focused on Pf4 and its host P. aeruginosa PAO1. Expanding from Pf4 and PAO1, this study explores diverse Pf phages infecting P. aeruginosa clinical isolates. We describe a simple technique targeting the Pf lysogeny maintenance gene, pflM (PA0718), that enables the effective elimination of Pf prophages from diverse P. aeruginosa hosts. The pflM gene shows diversity among different Pf phage isolates; however, all examined pflM alleles encode the DUF5447 domain. We demonstrate that pflM deletion results in prophage excision but not replication, leading to total prophage loss, indicating a role for lysis/lysogeny decisions for the DUF5447 domain. This study also assesses the effects different Pf phages have on host quorum sensing, biofilm formation, pigment production, and virulence against the bacterivorous nematode Caenorhabditis elegans. We find that Pf phages have strain-specific impacts on quorum sensing and biofilm formation, but nearly all suppress pigment production and increase C. elegans avoidance behavior. Collectively, this research not only introduces a valuable tool for Pf prophage elimination from diverse P. aeruginosa isolates but also advances our understanding of the complex relationship between P. aeruginosa and filamentous Pf phages.IMPORTANCEPseudomonas aeruginosa is an opportunistic bacterial pathogen that is frequently infected by filamentous Pf phages (viruses) that integrate into its chromosome, affecting behavior. Although prior work has focused on Pf4 and PAO1, this study investigates diverse Pf in clinical isolates. A simple method targeting the deletion of the Pf lysogeny maintenance gene pflM (PA0718) effectively eliminates Pf prophages from clinical isolates. The research evaluates the impact Pf prophages have on bacterial quorum sensing, biofilm formation, and virulence phenotypes. This work introduces a valuable tool to eliminate Pf prophages from clinical isolates and advances our understanding of P. aeruginosa and filamentous Pf phage interactions.


Assuntos
Prófagos , Pseudomonas aeruginosa , Percepção de Quorum , Biofilmes/crescimento & desenvolvimento , Caenorhabditis elegans/microbiologia , Caenorhabditis elegans/virologia , Lisogenia , Prófagos/genética , Prófagos/fisiologia , Pseudomonas aeruginosa/virologia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/patogenicidade , Pseudomonas aeruginosa/fisiologia , Infecções por Pseudomonas/microbiologia , Fagos de Pseudomonas/genética , Fagos de Pseudomonas/fisiologia , Virulência
8.
Diabetologia ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967666

RESUMO

AIMS/HYPOTHESIS: Disruption of pancreatic islet function and glucose homeostasis can lead to the development of sustained hyperglycaemia, beta cell glucotoxicity and subsequently type 2 diabetes. In this study, we explored the effects of in vitro hyperglycaemic conditions on human pancreatic islet gene expression across 24 h in six pancreatic cell types: alpha; beta; gamma; delta; ductal; and acinar. We hypothesised that genes associated with hyperglycaemic conditions may be relevant to the onset and progression of diabetes. METHODS: We exposed human pancreatic islets from two donors to low (2.8 mmol/l) and high (15.0 mmol/l) glucose concentrations over 24 h in vitro. To assess the transcriptome, we performed single-cell RNA-seq (scRNA-seq) at seven time points. We modelled time as both a discrete and continuous variable to determine momentary and longitudinal changes in transcription associated with islet time in culture or glucose exposure. Additionally, we integrated genomic features and genetic summary statistics to nominate candidate effector genes. For three of these genes, we functionally characterised the effect on insulin production and secretion using CRISPR interference to knock down gene expression in EndoC-ßH1 cells, followed by a glucose-stimulated insulin secretion assay. RESULTS: In the discrete time models, we identified 1344 genes associated with time and 668 genes associated with glucose exposure across all cell types and time points. In the continuous time models, we identified 1311 genes associated with time, 345 genes associated with glucose exposure and 418 genes associated with interaction effects between time and glucose across all cell types. By integrating these expression profiles with summary statistics from genetic association studies, we identified 2449 candidate effector genes for type 2 diabetes, HbA1c, random blood glucose and fasting blood glucose. Of these candidate effector genes, we showed that three (ERO1B, HNRNPA2B1 and RHOBTB3) exhibited an effect on glucose-stimulated insulin production and secretion in EndoC-ßH1 cells. CONCLUSIONS/INTERPRETATION: The findings of our study provide an in-depth characterisation of the 24 h transcriptomic response of human pancreatic islets to glucose exposure at a single-cell resolution. By integrating differentially expressed genes with genetic signals for type 2 diabetes and glucose-related traits, we provide insights into the molecular mechanisms underlying glucose homeostasis. Finally, we provide functional evidence to support the role of three candidate effector genes in insulin secretion and production. DATA AVAILABILITY: The scRNA-seq data from the 24 h glucose exposure experiment performed in this study are available in the database of Genotypes and Phenotypes (dbGap; https://www.ncbi.nlm.nih.gov/gap/ ) with accession no. phs001188.v3.p1. Study metadata and summary statistics for the differential expression, gene set enrichment and candidate effector gene prediction analyses are available in the Zenodo data repository ( https://zenodo.org/ ) under accession number 11123248. The code used in this study is publicly available at https://github.com/CollinsLabBioComp/publication-islet_glucose_timecourse .

9.
Phys Rev Lett ; 133(7): 070404, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39213560

RESUMO

A key question in the thermodynamics of open quantum systems is how to partition thermodynamic quantities such as entropy, work, and internal energy between the system and its environment. We show that the only partition under which entropy is nonsingular is based on a partition of Hilbert space, which assigns half the system-environment coupling to the system and half to the environment. However, quantum work partitions nontrivially under Hilbert-space partition, and we derive a work sum rule that accounts for quantum work at a distance. All state functions of the system are shown to be path independent once this nonlocal quantum work is properly accounted for. Our results are illustrated with application to a driven resonant level strongly coupled to a reservoir.

10.
J Gen Intern Med ; 39(6): 1037-1047, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38302812

RESUMO

INTRODUCTION: Healthcare advances are hindered by underrepresentation in prospective research; sociodemographic, data, and measurement infidelity in retrospective research; and a paucity of guidelines surrounding equitable research practices. OBJECTIVE: The Joint Research Practices Working Group was created in 2021 to develop and disseminate guidelines for the conduct of inclusive and equitable research. METHODS: Volunteer faculty and staff from two research centers at the University of Pennsylvania initiated a multi-pronged approach to guideline development, including literature searches, center-level feedback, and mutual learning with local experts. RESULTS: We developed guidelines for (1) participant payment and incentives; (2) language interpretation and translation; (3) plain language in research communications; (4) readability of study materials; and (5) inclusive language for scientific communications. Key recommendations include (1) offer cash payments and multiple payment options to participants when required actions are completed; (2) identify top languages of your target population, map points of contact, and determine available interpretation and translation resources; (3) assess reading levels of materials and simplify language, targeting 6th- to 8th-grade reading levels; (4) improve readability through text formatting and style, symbols, and visuals; and (5) use specific, humanizing terms as adjectives rather than nouns. CONCLUSIONS: Diversity, inclusion, and access are critical values for research conduct that promotes justice and equity. These values can be operationalized through organizational commitment that combines bottom-up and top-down approaches and through partnerships across organizations that promote mutual learning and synergy. While our guidelines represent best practices at one time, we recognize that practices evolve and need to be evaluated continuously for accuracy and relevance. Our intention is to bring awareness to these critical topics and form a foundation for important conversations surrounding equitable and inclusive research practices.


Assuntos
Pesquisa Biomédica , Humanos , Pesquisa Biomédica/normas , Centros Médicos Acadêmicos/organização & administração , Centros Médicos Acadêmicos/normas
11.
PLoS Comput Biol ; 19(1): e1009499, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36652468

RESUMO

The goal of this study is to calibrate a multiscale model of tumor angiogenesis with time-resolved data to allow for systematic testing of mathematical predictions of vascular sprouting. The multi-scale model consists of an agent-based description of tumor and endothelial cell dynamics coupled to a continuum model of vascular endothelial growth factor concentration. First, we calibrate ordinary differential equation models to time-resolved protein concentration data to estimate the rates of secretion and consumption of vascular endothelial growth factor by endothelial and tumor cells, respectively. These parameters are then input into the multiscale tumor angiogenesis model, and the remaining model parameters are then calibrated to time resolved confocal microscopy images obtained within a 3D vascularized microfluidic platform. The microfluidic platform mimics a functional blood vessel with a surrounding collagen matrix seeded with inflammatory breast cancer cells, which induce tumor angiogenesis. Once the multi-scale model is fully parameterized, we forecast the spatiotemporal distribution of vascular sprouts at future time points and directly compare the predictions to experimentally measured data. We assess the ability of our model to globally recapitulate angiogenic vasculature density, resulting in an average relative calibration error of 17.7% ± 6.3% and an average prediction error of 20.2% ± 4% and 21.7% ± 3.6% using one and four calibrated parameters, respectively. We then assess the model's ability to predict local vessel morphology (individualized vessel structure as opposed to global vascular density), initialized with the first time point and calibrated with two intermediate time points. In this study, we have rigorously calibrated a mechanism-based, multiscale, mathematical model of angiogenic sprouting to multimodal experimental data to make specific, testable predictions.


Assuntos
Microfluídica , Fator A de Crescimento do Endotélio Vascular , Humanos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Neovascularização Fisiológica , Neovascularização Patológica/patologia , Fatores de Crescimento do Endotélio Vascular , Microscopia Confocal
12.
J Shoulder Elbow Surg ; 33(6S): S74-S79, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38244834

RESUMO

BACKGROUND: Postoperative scapular stress fractures (SSFs) are a formidable problem after reverse shoulder arthroplasty (RSA). Less is known about patients who have these fractures preoperatively. The primary aim of this study was to examine postoperative satisfaction in patients undergoing primary RSA who have preoperative SSF and compared to a matched cohort without preoperative fracture. The secondary aim was to examine the differences in patient-reported outcomes between and within study cohorts. METHODS: A retrospective chart review of primary RSAs performed by a single surgeon from 2000 to 2020 was conducted. Patients diagnosed with cuff tear arthropathy (CTA), massive cuff tear (MCT), or rheumatoid arthritis (RA) were included. Five hundred twenty-five shoulders met inclusion criteria. Fractures identified on preoperative computed tomography scans were divided into 3 groups: (1) os acromiale, (2) multifragments (MFs), and (3) Levy types. Seventy-two shoulders had an occurrence of SSF. The remaining 453 shoulders were separated into a nonfractured cohort. American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) and visual analog scale (VAS) scores were compared pre- and postoperatively in the total fracture group and the nonfractured group cohort. The multifragment subgroup was also compared to the pooled Os/Levy subgroup. RESULTS: The total incidence of SSF in all shoulders was 13.7%. There was a difference in satisfaction scores at all time points between the nonfracture (7.9 ± 2.8) and total fracture group (5.4 ± 3.6, P < .001, at last visit). There was also a greater ASES total score in the nonfractured group vs the total fracture group at the final visit (69.4 ± 23.4 and 62.1 ± 24.2; P = .02). The MF group had worse ASES functional or VAS functional scores than the Os/Levy group at all time points: at 1 year, ASES function: MF 24.2 ± 14.5 and Os/Levy 30.7 ± 14.2 (P = .045); at 2 years, ASES function: MF 21.4 ± 14.4 and Os/Levy 35.5 ± 10.6 (P < .001); and at last follow-up, VAS function: MF 4.8 ± 2.8 and Os/Levy 6.4 ± 3.2 (P = .023). DISCUSSION: Scapular fractures were proportionally most common in patients diagnosed with CTA (16.3%) compared with a 9.2% and 8.6% incidence in patients diagnosed with MCT and RA, respectively. Patients with preoperative SSF still see an improvement in ASES scores after RSA but do have lower satisfaction scores compared with the nonfractured cohort. The multifragment fracture group has lower functional and satisfaction scores at all postoperative time points compared with both the nonfracture and the Os/Levy fracture group.


Assuntos
Artroplastia do Ombro , Escápula , Humanos , Artroplastia do Ombro/efeitos adversos , Masculino , Feminino , Estudos Retrospectivos , Idoso , Escápula/lesões , Escápula/cirurgia , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Fraturas Ósseas/cirurgia , Satisfação do Paciente , Medidas de Resultados Relatados pelo Paciente
13.
J Shoulder Elbow Surg ; 33(6S): S80-S85, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38182021

RESUMO

BACKGROUND: The goal of treating periprosthetic infection, besides its eradication, is to avoid recurrence. The purpose of this study was to evaluate the impact of increasing Infection Severity (IS) score (based on the 2018 International Consensus Meeting on Orthopedic Infections statement), single-stage revision, and pathogenicity of the infective organism on the risk of infection recurrence. METHODS: A database of 790 revisions performed by a single surgeon from 2004-2020 was reviewed for patients with minimum 2-year follow-up and ≥1 positive culture finding and/or pathology result from the revision surgical procedure. In total, 157 cases performed in 144 patients met the inclusion criteria. These cases were then categorized by infection probability (IS score) according to the 2018 consensus statement. Of 157 cases, 46 (29%) were classified as definitely or probably infected; 25 (16%), possibly infected; and 86 (55%), unlikely to be infected. Additionally, patients were grouped by single-stage surgery and pathogenicity of the infective organism. RESULTS: A recurrence in this study was classified as the growth of the same organism in any patient requiring revision surgery. The 86 cases in the group with unlikely infection showed a recurrence rate of 2.3%. The 25 cases in the group with possible infection showed a recurrence rate of 12%. The 46 cases in the group with definite or probable infection showed a recurrence rate of 17.4%. Patients in the definite/probable infection group had a higher rate of recurrence than those in the groups with possible infection and unlikely infection (P = .009). The IS score was higher in the recurrence group than the non-recurrence group (7.5 ± 4.3 vs. 3.9 ± 3.4, P < .001). Overall, patients who underwent 1-stage revision had a 5.0% recurrence rate, but among the 34 patients with an infection classification of definite or probable who underwent 1-stage revision, the recurrence rate was 5.9%. Cases of highly virulent methicillin-resistant Staphylococcus aureus also showed a recurrence rate of 30.8% compared with 4.0% and 5.9% for Cutibacterium acnes and coagulase-negative staphylococci, respectively (P = .005). CONCLUSION: Recurrent infection after treatment of a periprosthetic infection is associated with increasing severity scores, as defined in the 2018 consensus statement, and more aggressive microorganisms. However, a single-stage surgical procedure, even in patients with higher IS scores, did not impart a significantly increased risk of recurrence.


Assuntos
Artroplastia do Ombro , Infecções Relacionadas à Prótese , Recidiva , Reoperação , Humanos , Infecções Relacionadas à Prótese/microbiologia , Infecções Relacionadas à Prótese/cirurgia , Infecções Relacionadas à Prótese/etiologia , Masculino , Feminino , Idoso , Artroplastia do Ombro/efeitos adversos , Pessoa de Meia-Idade , Fatores de Risco , Estudos Retrospectivos , Prótese de Ombro/efeitos adversos
14.
J Pediatr Orthop ; 44(6): e496-e503, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38647138

RESUMO

OBJECTIVE: Infant hip dislocations benefit from early detection and treatment for optimal outcomes. Prior studies have identified that there remains wide variability in the success rate of bracing between institutions. Although there are standardized methods to screen infants for hip dysplasia, there are no clear guidelines regarding how to image a child being treated for a hip dislocation with a Pavlik harness. As a result, there is substantial variability in how treatment success or failure is monitored between and within institutions. The goal of our study is to determine whether a standardized in-harness imaging protocol improves outcomes and the likelihood of successful treatment for dislocated hips being treated with the Pavlik harness. METHODS: All patients with hip dislocations and pretreatment ultrasound (US) were included from July 2018 to July 2022. A new institutional US protocol was implemented in July 2020, during which standardized in-harness imaging was obtained for patients with hip dislocations. Patients treated before the implementation of standardized in-harness imaging were categorized as nonstandardized and after implementation as a standardized group. Outcomes were compared between standardized and nonstandardized groups. P <0.05 determined the statistical significance. RESULTS: One hundred twenty-eight hips met the inclusion criteria (n = 97 patients). The mean age at diagnosis was 41.6 ± 23.4 days and was predominantly female (85.6%). There was no significant difference between the patients' demographics and baseline clinical characteristics between the standardized and nonstandardized groups. Pavlik harness success rate was significantly higher in the standardized group (85% vs 60%, P = 0.0024). Twenty-eight hips in the nonstandardized group remained dislocated and were indicated for surgical treatment, whereas only 8 hips remained dislocated in the standardized group and necessitated closed or open reduction. CONCLUSIONS: Standardization of in-harness imaging for patients undergoing treatment for developmental hip dislocations can significantly improve the Pavlik harness success rate. These findings emphasize the importance of obtaining images with the hip in flexion and abduction to prevent inadvertent stress during US evaluation for hips that have not yet stabilized, which may lead to premature cessation of the Pavlik harness. LEVEL OF EVIDENCE: Level III.


Assuntos
Braquetes , Luxação Congênita de Quadril , Ultrassonografia , Humanos , Feminino , Masculino , Ultrassonografia/métodos , Lactente , Luxação Congênita de Quadril/terapia , Luxação Congênita de Quadril/diagnóstico por imagem , Resultado do Tratamento , Recém-Nascido , Estudos Retrospectivos , Protocolos Clínicos
15.
J Biol Chem ; 298(11): 102592, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36244451

RESUMO

Nonsense-mediated mRNA decay (NMD) is a quality control pathway in eukaryotes that continuously monitors mRNA transcripts to ensure truncated polypeptides are not produced. The expression of many normal mRNAs that encode full-length polypeptides is also regulated by this pathway. Such transcript surveillance by NMD is intimately linked to translation termination. When a ribosome terminates translation at a normal termination codon, NMD is not activated, and mRNA can undergo repeated rounds of translation. On the other hand, when translation termination is deemed abnormal, such as that on a premature termination codon, it leads to a series of poorly understood events involving the NMD pathway, which destabilizes the transcript. In this review, we summarize our current understanding of how the NMD machinery interfaces with the translation termination factors to initiate NMD. We also discuss a variety of cis-acting sequence contexts and trans-acting factors that can cause readthrough, ribosome reinitiation, or ribosome frameshifting at stop codons predicted to induce NMD. These alternative outcomes can lead to the ribosome translating downstream of such stop codons and hence the transcript escaping NMD. NMD escape via these mechanisms can have wide-ranging implications on human health, from being exploited by viruses to hijack host cell systems to being harnessed as potential therapeutic possibilities to treat genetic diseases.


Assuntos
Degradação do RNAm Mediada por Códon sem Sentido , Ribossomos , Humanos , Códon de Terminação/metabolismo , Ribossomos/genética , Ribossomos/metabolismo , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
16.
Infect Immun ; 91(2): e0050022, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36715551

RESUMO

The peptidoglycan of Staphylococcus aureus is a critical cell envelope constituent and virulence factor that subverts host immune defenses and provides protection against environmental stressors. Peptidoglycan chains of the S. aureus cell wall are processed to characteristically short lengths by the glucosaminidase SagB. It is well established that peptidoglycan is an important pathogen-associated molecular pattern (PAMP) that is recognized by the host innate immune system and promotes production of proinflammatory cytokines, including interleukin-1ß (IL-1ß). However, how bacterial processing of peptidoglycan drives IL-1ß production is comparatively unexplored. Here, we tested the involvement of staphylococcal glucosaminidases in shaping innate immune responses and identified SagB as a mediator of IL-1ß production. A ΔsagB mutant fails to promote IL-1ß production by macrophages and dendritic cells, and processing of peptidoglycan by SagB is essential for this response. SagB-dependent IL-1ß production by macrophages is independent of canonical pattern recognition receptor engagement and NLRP3 inflammasome-mediated caspase activity. Instead, treatment of macrophages with heat-killed cells from a ΔsagB mutant leads to reduced caspase-independent cleavage of pro-IL-1ß, resulting in accumulation of the pro form in the macrophage cytosol. Furthermore, SagB is required for virulence in systemic infection and promotes IL-1ß production in a skin and soft tissue infection model. Taken together, our results suggest that the length of S. aureus cell wall glycan chains can drive IL-1ß production by innate immune cells through a previously undescribed mechanism related to IL-1ß maturation.


Assuntos
Peptidoglicano , Staphylococcus aureus , Hexosaminidases , Inflamassomos , Interleucina-1beta , Caspases , Parede Celular , Proteína 3 que Contém Domínio de Pirina da Família NLR , Caspase 1
17.
EMBO J ; 38(22): e101681, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31583744

RESUMO

Epigenetic modifications operate in concert to maintain cell identity, yet how these interconnected networks suppress alternative cell fates remains unknown. Here, we uncover a link between the removal of repressive histone H3K9 methylation and DNA methylation during the reprogramming of somatic cells to pluripotency. The H3K9me2 demethylase, Kdm3b, transcriptionally controls DNA hydroxymethylase Tet1 expression. Unexpectedly, in the absence of Kdm3b, loci that must be DNA demethylated are trapped in an intermediate hydroxymethylated (5hmC) state and do not resolve to unmethylated cytosine. Ectopic 5hmC trapping precludes the chromatin association of master pluripotency factor, POU5F1, and pluripotent gene activation. Increased Tet1 expression is important for the later intermediates of the reprogramming process. Taken together, coordinated removal of distinct chromatin modifications appears to be an important mechanism for altering cell identity.


Assuntos
Linhagem da Célula/genética , Reprogramação Celular , Cromatina/genética , Metilação de DNA , Epigênese Genética , Histonas/genética , Células-Tronco Pluripotentes Induzidas/citologia , Animais , Células Cultivadas , Proteínas de Ligação a DNA/fisiologia , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco Pluripotentes Induzidas/metabolismo , Histona Desmetilases com o Domínio Jumonji/fisiologia , Camundongos , Camundongos Knockout , Fator 3 de Transcrição de Octâmero/metabolismo , Proteínas Proto-Oncogênicas/fisiologia
18.
Lancet ; 400(10348): 295-327, 2022 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-35871816

RESUMO

BACKGROUND: Meeting the contraceptive needs of women of reproductive age is beneficial for the health of women and children, and the economic and social empowerment of women. Higher rates of contraceptive coverage have been linked to the availability of a more diverse range of contraceptive methods. We present estimates of the contraceptive prevalence rate (CPR), modern contraceptive prevalence rate (mCPR), demand satisfied, and the method of contraception used for both partnered and unpartnered women for 5-year age groups in 204 countries and territories between 1970 and 2019. METHODS: We used 1162 population-based surveys capturing contraceptive use among women between 1970 and 2019, in which women of reproductive age (15-49 years) self-reported their, or their partner's, current use of contraception for family planning purposes. Spatiotemporal Gaussian process regression was used to generate estimates of the CPR, mCPR, demand satisfied, and method mix by age and marital status. We assessed how age-specific mCPR and demand satisfied changed with the Socio-demographic Index (SDI), a measure of social and economic development, using the meta-regression Bayesian, regularised, trimmed method from the Global Burden of Diseases, Injuries, and Risk Factors Study. FINDINGS: In 2019, 162·9 million (95% uncertainty interval [UI] 155·6-170·2) women had unmet need for contraception, of whom 29·3% (27·9-30·6) resided in sub-Saharan Africa and 27·2% (24·4-30·3) resided in south Asia. Women aged 15-19 years (64·8% [62·9-66·7]) and 20-24 years (71·9% [68·9-74·2]) had the lowest rates of demand satisfied, with 43·2 million (95% UI 39·3-48·0) women aged 15-24 years with unmet need in 2019. The mCPR and demand satisfied among women aged 15-19 years were substantially lower than among women aged 20-49 years at SDI values below 60 (on a 0-100 scale), but began to equalise as SDI increased above 60. Between 1970 and 2019, the global mCPR increased by 20·1 percentage points (95% UI 18·7-21·6). During this time, traditional methods declined as a proportion of all contraceptive methods, whereas the use of implants, injections, female sterilisation, and condoms increased. Method mix differs substantially depending on age and geography, with the share of female sterilisation increasing with age and comprising more than 50% of methods in use in south Asia. In 28 countries, one method was used by more than 50% of users in 2019. INTERPRETATION: The dominance of one contraceptive method in some locations raises the question of whether family planning policies should aim to expand method mix or invest in making existing methods more accessible. Lower rates of demand satisfied among women aged 15-24 years are also concerning because unintended pregnancies before age 25 years can forestall or eliminate education and employment opportunities that lead to social and economic empowerment. Policy makers should strive to tailor family planning programmes to the preferences of the groups with the most need, while maintaining the programmes used by existing users. FUNDING: Bill & Melinda Gates Foundation.


Assuntos
Anticoncepção , Carga Global da Doença , Teorema de Bayes , Criança , Anticoncepcionais , Serviços de Planejamento Familiar , Feminino , Humanos , Estado Civil , Gravidez , Prevalência
19.
Am J Physiol Heart Circ Physiol ; 324(6): H762-H775, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36930656

RESUMO

Plasma soluble prorenin receptor (sPRR) displays sexual dimorphism and is higher in women with type 2 diabetes mellitus (T2DM). However, the contribution of plasma sPRR to the development of vascular complications in T2DM remains unclear. We investigated if plasma sPRR contributes to sex differences in the activation of the systemic renin-angiotensin-aldosterone system (RAAS) and vascular damage in a model of high-fat diet (HFD)-induced T2DM. Male and female C57BL/6J mice were fed either a normal fat diet (NFD) or an HFD for 28 wk to assess changes in blood pressure, cardiometabolic phenotype, plasma prorenin/renin, sPRR, and ANG II. After completing dietary protocols, tissues were collected from males to assess vascular reactivity and aortic reactive oxygen species (ROS). A cohort of male mice was used to determine the direct contribution of increased systemic sPRR by infusion. To investigate the role of ovarian hormones, ovariectomy (OVX) was performed at 32 wk in females fed either an NFD or HFD. Significant sex differences were found after 28 wk of HFD, where only males developed T2DM and increased plasma prorenin/renin, sPRR, and ANG II. T2DM in males was accompanied by nondipping hypertension, carotid artery stiffening, and aortic ROS. sPRR infusion in males induced vascular thickening instead of material stiffening caused by HFD-induced T2DM. While intact females were less prone to T2DM, OVX increased plasma prorenin/renin, sPRR, and systolic blood pressure. These data suggest that sPRR is a novel indicator of systemic RAAS activation and reflects the onset of vascular complications during T2DM regulated by sex.NEW & NOTEWORTHY High-fat diet (HFD) for 28 wk leads to type 2 diabetes mellitus (T2DM) phenotype, concomitant with increased plasma soluble prorenin receptor (sPRR), nondipping blood pressure, and vascular stiffness in male mice. HFD-fed female mice exhibiting a preserved cardiometabolic phenotype until ovariectomy revealed increased plasma sPRR and blood pressure. Plasma sPRR may indicate the status of systemic renin-angiotensin-aldosterone system (RAAS) activation and the onset of vascular complications during T2DM in a sex-dependent manner.


Assuntos
Diabetes Mellitus Tipo 2 , Hipertensão , ATPases Vacuolares Próton-Translocadoras , Feminino , Masculino , Camundongos , Animais , Renina , Receptor de Pró-Renina , Dieta Hiperlipídica/efeitos adversos , Espécies Reativas de Oxigênio , Camundongos Endogâmicos C57BL , Sistema Renina-Angiotensina/genética , Receptores de Superfície Celular/genética , Pressão Sanguínea
20.
J Virol ; 96(17): e0123222, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36037480

RESUMO

Enteroviruses initiate infection in the gastrointestinal tract, and sex is often a biological variable that impacts pathogenesis. Previous data suggest that sex hormones can influence the intestinal replication of Coxsackievirus B3 (CVB3), an enterovirus in the Picornaviridae family. However, the specific sex hormone(s) that regulates intestinal CVB3 replication is poorly understood. To determine if testosterone promotes intestinal CVB3 replication, we orally inoculated male and female Ifnar-/- mice that were treated with either placebo or testosterone-filled capsules. Following oral inoculation, we found that the testosterone-treated male and female mice shed significantly more CVB3 in their feces than did the placebo-treated mice, indicating that testosterone enhances intestinal replication. Similarly, testosterone enhanced viral dissemination in both sexes, as we observed higher viral loads in peripheral tissues following infection. Further, the testosterone-treated male mice also had a higher mortality rate than did the testosterone-depleted male mice. Finally, we observed that testosterone significantly affected the immune response to CVB3. We found that testosterone broadly increased proinflammatory cytokines and chemokines while decreasing the number of splenic B cells and dendritic cells following CVB3 infection. Moreover, while testosterone did not affect the early CD4 T cell response to CVB3, testosterone reduced the activation of CD8 T cells. These data indicate that testosterone can promote intestinal CVB3 replication and dissemination while also impacting the subsequent viral immune response. IMPORTANCE Biological sex plays a significant role in the outcomes of various infections and diseases. The impact of sex hormones on the intestinal replication and dissemination of Coxsackievirus B3 remains poorly understood. Using an oral inoculation model, we found that testosterone enhances CVB3 shedding and dissemination in male and female mice. Further, testosterone can alter the immune response to CVB3. This work highlights the role of testosterone in CVB3 pathogenesis and suggests that sex hormones can impact the replication and dissemination of enteric viruses.


Assuntos
Infecções por Coxsackievirus/imunologia , Testosterona/metabolismo , Animais , Infecções por Coxsackievirus/metabolismo , Infecções por Coxsackievirus/virologia , Modelos Animais de Doenças , Feminino , Interações Hospedeiro-Patógeno , Masculino , Camundongos , Replicação Viral
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