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1.
J Gen Intern Med ; 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39354250

RESUMEN

BACKGROUND: Data on the potential protective effect of psychological safety (PS) on well-being and satisfaction among physicians are lacking. OBJECTIVE: We sought to examine (1) prevalence of PS; (2) relationship between PS, burnout, and intent to leave one's job (ILJ); and (3) demographic and occupational factors associated with PS within our physician faculty. DESIGN: Participants: An institution-wide survey was sent to all faculty within our eight-hospital health system, between July and September 2022. MAIN MEASURES: PS was assessed using the seven-item Fearless Organization Questionnaire and burnout with the Maslach Burnout Inventory-2. Demographics and a measure of ILJ were assessed. Multivariable logistic regression analyses were conducted to determine associations between PS, burnout, ILJ, and demographic and occupational correlates of PS. KEY RESULTS: A total of 867 out of 3086 total estimated clinical faculty members (28.1%) participated in the survey. The majority were 40 and older (67.4%), female (51.9%), white (60.0%), and married/partnered (80.4%); worked in ambulatory care departments (53.7%); and ranked assistant or associate professors (75.8%). On average, 57.6% of physicians evaluated their workplace as psychologically safe (range across items = 40.9-69.9%), with 35.2% screening positive for burnout and 13.4% reporting ILJ. After adjusting for demographic and occupational characteristics, each standard deviation unit increase in PS scores was associated with 27% lower odds of screening positive for burnout (odds ratio (OR) = 0.73, 95% confidence interval (CI) = 0.63-0.84) and 38% lower odds of ILJ (OR = 0.62, 95% CI = 0.52-0.74). Female gender was associated with lower scores of PS. CONCLUSIONS: A majority of faculty physicians reported working in a psychologically safe environment. Greater PS was associated with lower odds of burnout and ILJ. Investment in gender and diversity equity training may be one concrete step in advancing PS in the workplace.

2.
J Neurochem ; 168(9): 2832-2847, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39361112

RESUMEN

Hippocampal neuronal plasticity is a fundamental process underpinning learning and memory formation and requiring elaborate molecular mechanisms that result in the dynamic remodelling of synaptic connectivity. The neurotrophic properties of midkine (Mdk) have been implicated in the development and repair of the nervous system, while Mdk knockout resulted in deficits in the formation of certain types of memory. The role of Mdk in the process of memory-associated neuronal plasticity, however, remains poorly understood. We investigated the learning-induced regulation of Mdk in spatial navigation and association learning using the water maze and the odour reward association learning paradigms, characterising a temporal profile of Mdk protein expression post-learning. Both learning events revealed similar patterns of upregulation of expression of the protein in the rat hippocampal dentate gyrus, which were rapid and transient. Moreover, administration of recombinant Mdk during the endogenous Mdk upregulation following learning enhanced memory in the water maze task revealing a pro-cognitive action of Mdk. We further show that, within the adult hippocampus, Mdk mRNA is predominantly expressed in granular and pyramidal neurons and that hippocampal neuronal Mdk expression is regulated by the canonical plasticity-associated neurotransmitter glutamate. Finally, we confirm that the positive action of Mdk on neurite outgrowth previously noted in cortical and cerebellar neurons extends to hippocampal neurons. Together, our findings suggest a role for Mdk in glutamate-mediated hippocampal neuronal plasticity important for long-term memory consolidation.


Asunto(s)
Hipocampo , Memoria , Midkina , Recompensa , Regulación hacia Arriba , Animales , Midkina/metabolismo , Masculino , Regulación hacia Arriba/fisiología , Ratas , Hipocampo/metabolismo , Memoria/fisiología , Aprendizaje por Asociación/fisiología , Aprendizaje por Laberinto/fisiología , Plasticidad Neuronal/fisiología , Aprendizaje Espacial/fisiología , Ratas Sprague-Dawley
3.
Science ; 386(6717): 69-75, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39361752

RESUMEN

Clostridioides difficile infection (CDI) is an urgent public health threat with limited preventative options. In this work, we developed a messenger RNA (mRNA)-lipid nanoparticle (LNP) vaccine targeting C. difficile toxins and virulence factors. This multivalent vaccine elicited robust and long-lived systemic and mucosal antigen-specific humoral and cellular immune responses across animal models, independent of changes to the intestinal microbiota. Vaccination protected mice from lethal CDI in both primary and recurrent infection models, and inclusion of non-toxin cellular and spore antigens improved decolonization of toxigenic C. difficile from the gastrointestinal tract. Our studies demonstrate mRNA-LNP vaccine technology as a promising platform for the development of novel C. difficile therapeutics with potential for limiting acute disease and promoting bacterial decolonization.


Asunto(s)
Toxinas Bacterianas , Vacunas Bacterianas , Clostridioides difficile , Infecciones por Clostridium , Nanopartículas , Animales , Clostridioides difficile/inmunología , Clostridioides difficile/genética , Ratones , Infecciones por Clostridium/prevención & control , Infecciones por Clostridium/inmunología , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/administración & dosificación , Toxinas Bacterianas/inmunología , Toxinas Bacterianas/genética , Modelos Animales de Enfermedad , ARN Mensajero/genética , Ratones Endogámicos C57BL , Femenino , Factores de Virulencia/genética , Factores de Virulencia/inmunología , Inmunidad Celular , Vacunas de ARNm , Inmunidad Humoral , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/genética , Microbioma Gastrointestinal , Liposomas
5.
Nat Metab ; 6(9): 1736-1755, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39242914

RESUMEN

Macrophage efferocytosis prevents apoptotic cell (AC) accumulation and triggers inflammation-resolution pathways. The mechanisms linking efferocytosis to resolution often involve changes in macrophage metabolism, but many gaps remain in our understanding of these processes. We now report that efferocytosis triggers an indoleamine 2,3-dioxygenase-1 (IDO1)-dependent tryptophan (Trp) metabolism pathway that promotes several key resolution processes, including the induction of pro-resolving proteins, such interleukin-10, and further enhancement of efferocytosis. The process begins with upregulation of Trp transport and metabolism, and it involves subsequent activation of the aryl hydrocarbon receptor (AhR) by the Trp metabolite kynurenine (Kyn). Through these mechanisms, macrophage IDO1 and AhR contribute to a proper resolution response in several different mouse models of efferocytosis-dependent tissue repair, notably during atherosclerosis regression induced by plasma low-density lipoprotein (LDL) lowering. These findings reveal an integrated metabolism programme in macrophages that links efferocytosis to resolution, with possible therapeutic implications for non-resolving chronic inflammatory diseases, notably atherosclerosis.


Asunto(s)
Indolamina-Pirrol 2,3,-Dioxigenasa , Macrófagos , Fagocitosis , Receptores de Hidrocarburo de Aril , Triptófano , Triptófano/metabolismo , Animales , Macrófagos/metabolismo , Ratones , Receptores de Hidrocarburo de Aril/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Quinurenina/metabolismo , Inflamación/metabolismo , Apoptosis , Aterosclerosis/metabolismo , Eferocitosis
6.
Proc Natl Acad Sci U S A ; 121(38): e2318386121, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39264743

RESUMEN

Capillarity-driven transport in nanoporous solids is widespread in nature and crucial for modern liquid-infused engineering materials. During imbibition, curved menisci driven by high negative Laplace pressures exert an enormous contractile load on the porous matrix. Due to the challenge of simultaneously monitoring imbibition and deformation with high spatial resolution, the resulting coupling of solid elasticity to liquid capillarity has remained largely unexplored. Here, we study water imbibition in mesoporous silica using optical imaging, gravimetry, and high-resolution dilatometry. In contrast to an expected Laplace pressure-induced contraction, we find a square-root-of-time expansion and an additional abrupt length increase when the menisci reach the top surface. The final expansion is absent when we stop the imbibition front inside the porous medium in a dynamic imbibition-evaporation equilibrium, as is typical for transpiration-driven hydraulic transport in plants, especially in trees. These peculiar deformation behaviors are validated by single-nanopore molecular dynamics simulations and described by a continuum model that highlights the importance of expansive surface stresses at the pore walls (Bangham effect) and the buildup or release of contractile Laplace pressures as menisci collectively advance, arrest, or disappear. Our model suggests that these observations apply to any imbibition process in nanopores, regardless of the liquid/solid combination, and that the Laplace contribution upon imbibition is precisely half that of vapor sorption, due to the linear pressure drop associated with viscous flow. Thus, simple deformation measurements can be used to quantify surface stresses and Laplace pressures or transport in a wide variety of natural and artificial porous media.

7.
World Neurosurg ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39242023

RESUMEN

OBJECTIVE: Few studies have reported the impact of telescoping flow diverters (FDs) in intracranial aneurysm treatment. Our study compared aneurysms treated using telescoping FDs to those treated with a single FD and identified predictors of telescoping. METHODS: This was a single-center retrospective review of a prospectively maintained database of aneurysms treated with FDs between 2011 and 2023. All patients who were treated with FDs for intracranial aneurysms were included in the study. RESULTS: The study comprised 750 patients with 750 aneurysms treated using 871 FDs. The study cohort was divided into 85 patients requiring telescoping FDs and 655 who did not. Rates of hemorrhage (7.1% vs. 1.8%, P < 0.001), symptomatic stroke (5.9% vs. 2.6, P < 0.001), and asymptomatic stroke (1.2% vs. 0.8%, P < 0.001) were significantly higher in the telescoping cohorts. At final follow-up, the rate of nonocclusion (9.8% vs. 5.1%, P = 0.029) and the rate of complete occlusion (88.5% vs. 81.1%, P = 0.029) were significantly higher in the telescoping cohort. On multivariate analysis, fusiform morphology (odds ratio [OR]: 2.4, 95% confidence interval [CI] 1.0-5.0, P = 0.03), increasing aneurysm height (OR: 1.0, 95% CI 1.0-1.1, P= 0.034), and the use of the Pipeline Embolization Device FD (OR: 2.4, 95% CI 1.3-4.4, P = 0.005) were independent predictors of telescoping. CONCLUSIONS: Aneurysms with fusiform morphology, increasing aneurysm height and those that underwent flow diversion using Pipeline Embolization Device had higher odds for telescoping. Significantly higher rates of angiographic occlusion with the use of telescoping FD add to the literature on its efficacy in treating aneurysms of varying morphology.

8.
Appl Microbiol Biotechnol ; 108(1): 475, 2024 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-39340650

RESUMEN

Trichothecenes are toxins produced by certain species from several fungal genera, including Aspergillus, Fusarium, Isaria, Paramyrothecium, Stachybotrys, Trichoderma, and Trichothecium. These toxins are of interest because they contribute to the toxigenicity, plant pathogenicity, and/or biological control activities of some fungi. All trichothecenes have the same core (12,13-epoxytrichothec-9-ene or EPT) structure but can differ from one another by the presence or absence of a macrocyclic ring formed from polyketide and isoprenoid substituents esterified to carbon atoms 4 and 15 of EPT, respectively. Genes required for formation and some modifications of EPT have been elucidated, but almost nothing is known about genes specific to the formation of the macrocyclic ring. Therefore, we used genomic, transcriptomic, metabolomic, and gene deletion analyses to identify genes that are required specifically for the formation of the macrocyclic ring. These analyses identified one gene, TRI24, that is predicted to encode an acyltransferase and that is required for macrocyclic ring formation during biosynthesis of macrocyclic trichothecenes by the fungus Paramyrothecium roridum. In addition, a TRI24 deletion mutant of P. roridum caused less severe disease symptoms on common bean and had less antifungal activity than its wild-type progenitor strain. We propose that the reduced aggressiveness and antifungal activity of the mutant resulted from its inability to produce trichothecenes with a macrocyclic ring. To our knowledge, this is the first report of a gene required specifically for the formation of the macrocyclic ring of trichothecenes and that loss of the macrocyclic ring of trichothecenes can alter the biological activities of a fungus. KEY POINTS: • TRI24 gene is found in all known macrocyclic trichothecene-producing fungi. • A tri24-deletion mutant exhibits a reduction in antifungal and plant disease activities. • TRI24 is the first described gene specific to macrocyclic trichothecene biosynthesis.


Asunto(s)
Tricotecenos , Tricotecenos/metabolismo , Tricotecenos/química , Enfermedades de las Plantas/microbiología , Eliminación de Gen , Compuestos Macrocíclicos/farmacología , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/metabolismo , Metabolómica , Genes Fúngicos , Perfilación de la Expresión Génica
9.
J Affect Disord ; 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39341292

RESUMEN

BACKGROUND: The suicide rate for United States military veterans is 1.5× higher than that of non-veterans. To meaningfully advance suicide prevention efforts, research is needed to delineate factors that differentiate veterans with suicide attempt/s, particularly in high-risk groups, e.g., major depressive disorder (MDD), from those with suicidal ideation (no history of attempt/s). The current study aimed to identify clinical, neurocognitive, and neuroimaging variables that differentiate suicide-severity groups in veterans with MDD. METHODS: Sixty-eight veterans with a DSM-5 diagnosis of MDD, including those with no ideation or suicide attempt (N = 21; MDD-SI/SA), ideation-only (N = 17; MDD + SI), and one-or-more suicide attempts (N = 30; MDD + SA; aborted, interrupted, actual attempts), participated in this study. Participants underwent a structured diagnostic interview, neurocognitive assessment, and 3 T-structural/diffusion tensor magnetic-resonance-imaging (MRI). Multinomial logistic regression models were conducted to identify variables that differentiated groups with respect to the severity of suicidal behavior. RESULTS: Relative to veterans with MDD-SI/SA, those with MDD + SA had significantly higher left cingulum fractional anisotropy, decreased attentional control on emotional-Stroop, and faster response time with intact accuracy on Go/No-Go. Relative to MDD + SI, MDD + SA had higher left cingulum fractional anisotropy and faster response time with intact accuracy on Go/No-Go. LIMITATIONS: Findings are based on retrospective, cross-sectional data and cannot identify causal relationships. Also, a healthy control group was not included given the study's focus on differentiating suicide profiles in MDD. CONCLUSIONS: This study suggests that MRI and neurocognition differentiate veterans with MDD along the suicide-risk spectrum and could inform suicide-risk stratification and prevention efforts in veterans and other vulnerable populations.

10.
J Environ Manage ; 369: 122392, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39232330

RESUMEN

Treatment Wetlands (TWs) are widely used for the treatment of domestic wastewater, with an increasing emphasis on provision of multiple co-benefits. However, concerns remain regarding achieving stringent phosphorus (P) discharge limits, system robustness and resilience, and associated guidance on system design and operation. Typically, where P removal is intended with a passive TW, surface flow (SF) systems are the chosen design type. This study analysed long-term monitoring datasets (2-30 years) from 85 full-scale SF TWs (25 m2 to 487 ha) treating domestic sewage with the influent load ranging from 2.17 to 54,779 m3/d, including secondary treatment, tertiary treatment, and combined sewer overflows treatment. The results showed median percentage removals of total P (TP) and orthophosphate (Ortho P) of 28% and 31%, respectively. Additionally, median areal mass removal rates were 5.13 and 2.87 gP/m2/yr, respectively. For tertiary SF TWs without targeted upstream P removal, 80% of the 44 systems achieved ≤3 mg/L annual average effluent total P. Tertiary SF TWs with targeted upstream P removal demonstrated high robustness, delivering stable effluent TP < 0.35 mg/L. Seasonality in removal achieved was absent from 85% of sites, with 95% of all systems demonstrating stable annual average effluent TP concentrations for up to a 30-year period. Only two out of 32 systems showed a significant increase in effluent TP concentration after the initial year and remained stable thereafter. The impact of different liner types on water infiltration, cost, and carbon footprint were analysed to quantify the impact of these commonly cited barriers to implementation of SF TW for P removal. The use of PVC enclosed between geotextile gave the lowest additional cost and carbon footprint associated with lining SF TWs. Whilst the P-k-C* model is considered the best practice for sizing SF TWs to achieve design pollutant reductions, it should be used with caution with further studies needed to more comprehensively understand the key design parameters and relationships that determine P removal performance in order to reliably predict effluent quality.


Asunto(s)
Fósforo , Eliminación de Residuos Líquidos , Aguas Residuales , Humedales , Fósforo/análisis , Aguas Residuales/química , Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos , Aguas del Alcantarillado/química , Contaminantes Químicos del Agua/análisis
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