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1.
Nat Immunol ; 19(7): 733-741, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29915297

RESUMEN

T cell-antigen receptor (TCR) signaling requires the sequential activities of the kinases Lck and Zap70. Upon TCR stimulation, Lck phosphorylates the TCR, thus leading to the recruitment, phosphorylation, and activation of Zap70. Lck binds and stabilizes phosho-Zap70 by using its SH2 domain, and Zap70 phosphorylates the critical adaptors LAT and SLP76, which coordinate downstream signaling. It is unclear whether phosphorylation of these adaptors occurs through passive diffusion or active recruitment. We report the discovery of a conserved proline-rich motif in LAT that mediates efficient LAT phosphorylation. Lck associates with this motif via its SH3 domain, and with phospho-Zap70 via its SH2 domain, thereby acting as a molecular bridge that facilitates the colocalization of Zap70 and LAT. Elimination of this proline-rich motif compromises TCR signaling and T cell development. These results demonstrate the remarkable multifunctionality of Lck, wherein each of its domains has evolved to orchestrate a distinct step in TCR signaling.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/metabolismo , Proteínas de la Membrana/metabolismo , Proteína Tirosina Quinasa ZAP-70/metabolismo , Proteínas Adaptadoras Transductoras de Señales/química , Secuencias de Aminoácidos , Animales , Células HEK293 , Humanos , Células Jurkat , Proteínas de la Membrana/química , Ratones , Ratones Endogámicos C57BL , Fosforilación , Prolina/análisis , Receptores de Antígenos de Linfocitos T/metabolismo , Timo/inmunología
2.
Cell ; 154(2): 285-96, 2013 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-23870120

RESUMEN

The endoplasmic reticulum (ER) often forms stacked membrane sheets, an arrangement that is likely required to accommodate a maximum of membrane-bound polysomes for secretory protein synthesis. How sheets are stacked is unknown. Here, we used improved staining and automated ultrathin sectioning electron microscopy methods to analyze stacked ER sheets in neuronal cells and secretory salivary gland cells of mice. Our results show that stacked ER sheets form a continuous membrane system in which the sheets are connected by twisted membrane surfaces with helical edges of left- or right-handedness. The three-dimensional structure of tightly stacked ER sheets resembles a parking garage, in which the different levels are connected by helicoidal ramps. A theoretical model explains the experimental observations and indicates that the structure corresponds to a minimum of elastic energy of sheet edges and surfaces. The structure allows the dense packing of ER sheets in the restricted space of a cell.


Asunto(s)
Células Acinares/ultraestructura , Encéfalo/citología , Retículo Endoplásmico/química , Retículo Endoplásmico/ultraestructura , Neuronas/ultraestructura , Glándula Parótida/citología , Células Acinares/química , Células Acinares/metabolismo , Animales , Retículo Endoplásmico/metabolismo , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo , Ratones , Microscopía Electrónica de Rastreo , Modelos Biológicos , Neuronas/química , Neuronas/metabolismo
3.
Plant Cell ; 35(7): 2592-2614, 2023 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-36970811

RESUMEN

Modulation of photoassimilate export from the chloroplast is essential for controlling the distribution of fixed carbon in the cell and maintaining optimum photosynthetic rates. In this study, we identified chloroplast TRIOSE PHOSPHATE/PHOSPHATE TRANSLOCATOR 2 (CreTPT2) and CreTPT3 in the green alga Chlamydomonas (Chlamydomonas reinhardtii), which exhibit similar substrate specificities but whose encoding genes are differentially expressed over the diurnal cycle. We focused mostly on CreTPT3 because of its high level of expression and the severe phenotype exhibited by tpt3 relative to tpt2 mutants. Null mutants for CreTPT3 had a pleiotropic phenotype that affected growth, photosynthetic activities, metabolite profiles, carbon partitioning, and organelle-specific accumulation of H2O2. These analyses demonstrated that CreTPT3 is a dominant conduit on the chloroplast envelope for the transport of photoassimilates. In addition, CreTPT3 can serve as a safety valve that moves excess reductant out of the chloroplast and appears to be essential for preventing cells from experiencing oxidative stress and accumulating reactive oxygen species, even under low/moderate light intensities. Finally, our studies indicate subfunctionalization of the TRIOSE PHOSPHATE/PHOSPHATE TRANSLOCATOR (CreTPT) transporters and suggest that there are differences in managing the export of photoassimilates from the chloroplasts of Chlamydomonas and vascular plants.


Asunto(s)
Chlamydomonas reinhardtii , Chlamydomonas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Chlamydomonas/genética , Chlamydomonas/metabolismo , Peróxido de Hidrógeno/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Fotosíntesis/genética , Carbono/metabolismo , Triosas/metabolismo , Fosfatos/metabolismo , Chlamydomonas reinhardtii/genética , Chlamydomonas reinhardtii/metabolismo
4.
Proc Natl Acad Sci U S A ; 119(23): e2121241119, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35639693

RESUMEN

The evolution of eukaryotic life was predicated on the development of organelles such as mitochondria and plastids. During this complex process of organellogenesis, the host cell and the engulfed prokaryote became genetically codependent, with the integration of genes from the endosymbiont into the host nuclear genome and subsequent gene loss from the endosymbiont. This process required that horizontally transferred genes become active and properly regulated despite inherent differences in genetic features between donor (endosymbiont) and recipient (host). Although this genetic reorganization is considered critical for early stages of organellogenesis, we have little knowledge about the mechanisms governing this process. The photosynthetic amoeba Paulinella micropora offers a unique opportunity to study early evolutionary events associated with organellogenesis and primary endosymbiosis. This amoeba harbors a "chromatophore," a nascent photosynthetic organelle derived from a relatively recent cyanobacterial association (∼120 million years ago) that is independent of the evolution of primary plastids in plants (initiated ∼1.5 billion years ago). Analysis of the genome and transcriptome of Paulinella revealed that retrotransposition of endosymbiont-derived nuclear genes was critical for their domestication in the host. These retrocopied genes involved in photoprotection in cyanobacteria became expanded gene families and were "rewired," acquiring light-responsive regulatory elements that function in the host. The establishment of host control of endosymbiont-derived genes likely enabled the cell to withstand photo-oxidative stress generated by oxygenic photosynthesis in the nascent organelle. These results provide insights into the genetic mechanisms and evolutionary pressures that facilitated the metabolic integration of the host­endosymbiont association and sustained the evolution of a photosynthetic organelle.


Asunto(s)
Amoeba , Evolución Biológica , Rhizaria , Simbiosis , Amoeba/genética , Eucariontes/genética , Plastidios/genética , Simbiosis/genética
5.
Nano Lett ; 24(8): 2481-2487, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38373326

RESUMEN

Comprehending the interaction between geometry and magnetism in three-dimensional (3D) nanostructures is important to understand the fundamental physics of domain wall (DW) formation and pinning. Here, we use focused-electron-beam-induced deposition to fabricate magnetic nanohelices with increasing helical curvature with height. Using electron tomography and Lorentz transmission electron microscopy, we reconstruct the 3D structure and magnetization of the nanohelices. The surface curvature, helical curvature, and torsion of the nanohelices are then quantified from the tomographic reconstructions. Furthermore, by using the experimental 3D reconstructions as inputs for micromagnetic simulations, we can reveal the influence of surface and helical curvature on the magnetic reversal mechanism. Hence, we can directly correlate the magnetic behavior of a 3D nanohelix to its experimental structure. These results demonstrate how the control of geometry in nanohelices can be utilized in the stabilization of DWs and control of the response of the nanostructure to applied magnetic fields.

6.
Nano Lett ; 24(5): 1531-1538, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38286029

RESUMEN

Two-dimensional (2D) van der Waals magnets comprise rich physics that can be exploited for spintronic applications. We investigate the interplay between spin-phonon coupling and spin textures in a 2D van der Waals magnet by combining magneto-Raman spectroscopy with cryogenic Lorentz transmission electron microscopy. We find that when stable skyrmion bubbles are formed in the 2D magnet, a field-dependent Raman shift can be observed, and this shift is absent for the 2D magnet prepared in its ferromagnetic state. Correlating these observations with numerical simulations that take into account field-dependent magnetic textures and spin--phonon coupling in the 2D magnet, we associate the Raman shift to field-induced modulations of the skyrmion bubbles and derive the existence of inhomogeneity in the skyrmion textures over the film thickness.

7.
J Clin Microbiol ; 62(3): e0149823, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38315022

RESUMEN

Sepsis caused by bloodstream infection (BSI) is a major healthcare burden and a leading cause of morbidity and mortality worldwide. Timely diagnosis is critical to optimize clinical outcome, as mortality rates rise every hour treatment is delayed. Blood culture remains the "gold standard" for diagnosis but is limited by its long turnaround time (1-7 days depending on the organism) and its potential to provide false-negative results due to interference by antimicrobial therapy or the presence of mixed (i.e., polymicrobial) infections. In this paper, we evaluated the performance of resistance and pathogen ID/BSI, a direct-from-specimen molecular assay. To reduce the false-positivity rate common with molecular methods, this assay isolates and detects genomic material only from viable microorganisms in the blood by incorporating a novel precursor step to selectively lyse host and non-viable microbial cells and remove cell-free genomic material prior to lysis and analysis of microbial cells. Here, we demonstrate that the assay is free of interference from host immune cells and common antimicrobial agents at elevated concentrations. We also demonstrate the accuracy of this technology in a prospective cohort pilot study of individuals with known sepsis/BSI status, including samples from both positive and negative individuals. IMPORTANCE: Blood culture remains the "gold standard" for the diagnosis of sepsis/bloodstream infection (BSI) but has many limitations which may lead to a delay in appropriate and accurate treatment in patients. Molecular diagnostic methods have the potential for markedly improving the management of such patients through faster turnaround times and increased accuracy. But molecular diagnostic methods have not been widely adopted for the identification of BSIs. By incorporating a precursor step of selective lysis of host and non-viable microorganisms, our resistance and pathogen ID (RaPID)/BSI molecular assay addresses many limitations of blood culture and other molecular assay. The RaPID/BSI assay has an approximate turnaround time of 4 hours, thereby significantly reducing the time to appropriate and accurate diagnosis of causative microorganisms in such patients. The short turnaround time also allows for close to real-time tracking of pathogenic clearance of microorganisms from the blood of these patients or if a change of antimicrobial regimen is required. Thus, the RaPID/BSI molecular assay helps with optimization of antimicrobial stewardship; prompt and accurate diagnosis of sepsis/BSI could help target timely treatment and reduce mortality and morbidity in such patients.


Asunto(s)
Antiinfecciosos , Bacteriemia , Infecciones Bacterianas , Enfermedades Transmisibles , Sepsis , Humanos , Proyectos Piloto , Sepsis/diagnóstico , Bacteriemia/diagnóstico
8.
Plant Physiol ; 192(2): 789-804, 2023 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-36960590

RESUMEN

Photosynthetic organisms frequently experience abiotic stress that restricts their growth and development. Under such circumstances, most absorbed solar energy cannot be used for CO2 fixation and can cause the photoproduction of reactive oxygen species (ROS) that can damage the photosynthetic reaction centers of PSI and PSII, resulting in a decline in primary productivity. This work describes a biological "switch" in the green alga Chlamydomonas reinhardtii that reversibly restricts photosynthetic electron transport (PET) at the cytochrome b6f (Cyt b6f) complex when the capacity for accepting electrons downstream of PSI is severely limited. We specifically show this restriction in STARCHLESS6 (sta6) mutant cells, which cannot synthesize starch when they are limited for nitrogen (growth inhibition) and subjected to a dark-to-light transition. This restriction represents a form of photosynthetic control that causes diminished electron flow to PSI and thereby prevents PSI photodamage but does not appear to rely on a ΔpH. Furthermore, when electron flow is restricted, the plastid alternative oxidase (PTOX) becomes active, functioning as an electron valve that dissipates some excitation energy absorbed by PSII and allows the formation of a proton motive force (PMF) that would drive some ATP production (potentially sustaining PSII repair and nonphotochemical quenching [NPQ]). The restriction at the Cyt b6f complex can be gradually relieved with continued illumination. This study provides insights into how PET responds to a marked reduction in availability of downstream electron acceptors and the protective mechanisms involved.


Asunto(s)
Complejo de Citocromo b6f , Electrones , Complejo de Citocromo b6f/metabolismo , Transporte de Electrón , Fotosíntesis/fisiología , Oxidación-Reducción , Oxidantes , Complejo de Proteína del Fotosistema I/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Luz
9.
J Anat ; 244(2): 343-357, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37837237

RESUMEN

Tlx1 encodes a transcription factor expressed in several craniofacial structures of developing mice. The role of Tlx1 in salivary gland development was examined using morphological and immunohistochemical analyses of Tlx1 null mice. Tlx1 is expressed in submandibular and sublingual glands but not parotid glands of neonatal and adult male and female C57Bl/6J (Tlx1+/+ ) mice. TLX1 protein was localized to the nuclei of terminal tubule cells, developing duct cells and mesenchymal cells in neonatal submandibular and sublingual glands, and to nuclei of duct cells and connective tissue cells in adult glands. Occasionally, TLX1 was observed in nuclei of epithelial cells in or adjacent to the acini. Submandibular glands were smaller and sublingual glands were larger in size in mutant mice (Tlx1-/- ) compared to wild-type mice. Differentiation of terminal tubule and proacinar cells of neonatal Tlx1-/- submandibular glands was abnormal; expression of their characteristic products, submandibular gland protein C and parotid secretory protein, respectively, was reduced. At 3 weeks postnatally, terminal tubule cells at the acinar-intercalated duct junction were poorly developed or absent in Tlx1-/- mice. Granular convoluted ducts in adult mutant mice were decreased, and epidermal growth factor and nerve growth factor expression were reduced. Along with normal acinar cell proteins, adult acinar cells of Tlx1-/- mice continued to express neonatal proteins and expressed parotid proteins not normally present in submandibular glands. Sublingual gland mucous acinar and serous demilune cell differentiation were altered. Tlx1 is necessary for proper differentiation of submandibular and sublingual gland acinar cells, and granular convoluted ducts. The mechanism(s) underlying Tlx1 regulation of salivary gland development and differentiation remains unknown.


Asunto(s)
Glándula Sublingual , Glándula Submandibular , Ratones , Animales , Masculino , Femenino , Glándula Submandibular/metabolismo , Glándula Sublingual/química , Glándula Sublingual/metabolismo , Glándula Parótida/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Proteínas de Homeodominio/metabolismo
10.
Neurochem Res ; 49(8): 2021-2037, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38814360

RESUMEN

Acetylcholine is the main neurotransmitter at the vertebrate neuromuscular junctions (NMJs). ACh exocytosis is precisely modulated by co-transmitter ATP and its metabolites. It is assumed that ATP/ADP effects on ACh release rely on activation of presynaptic Gi protein-coupled P2Y13 receptors. However, downstream signaling mechanism of ATP/ADP-mediated modulation of neuromuscular transmission remains elusive. Using microelectrode recording and fluorescent indicators, the mechanism underlying purinergic regulation was studied in the mouse diaphragm NMJs. Pharmacological stimulation of purinoceptors with ADP decreased synaptic vesicle exocytosis evoked by both low and higher frequency stimulation. This inhibitory action was suppressed by antagonists of P2Y13 receptors (MRS 2211), Ca2+ mobilization (TMB8), protein kinase C (chelerythrine) and NADPH oxidase (VAS2870) as well as antioxidants. This suggests the participation of Ca2+ and reactive oxygen species (ROS) in the ADP-triggered signaling. Indeed, ADP caused an increase in cytosolic Ca2+ with subsequent elevation of ROS levels. The elevation of [Ca2+]in was blocked by MRS 2211 and TMB8, whereas upregulation of ROS was prevented by pertussis toxin (inhibitor of Gi protein) and VAS2870. Targeting the main components of lipid rafts, cholesterol and sphingomyelin, suppressed P2Y13 receptor-dependent attenuation of exocytosis and ADP-induced enhancement of ROS production. Inhibition of P2Y13 receptors decreased ROS production and increased the rate of exocytosis during intense activity. Thus, suppression of neuromuscular transmission by exogenous ADP or endogenous ATP can rely on P2Y13 receptor/Gi protein/Ca2+/protein kinase C/NADPH oxidase/ROS signaling, which is coordinated in a lipid raft-dependent manner.


Asunto(s)
Microdominios de Membrana , Unión Neuromuscular , Oxidación-Reducción , Transducción de Señal , Transmisión Sináptica , Animales , Unión Neuromuscular/metabolismo , Unión Neuromuscular/efectos de los fármacos , Microdominios de Membrana/metabolismo , Transmisión Sináptica/fisiología , Transmisión Sináptica/efectos de los fármacos , Ratones , Transducción de Señal/fisiología , Transducción de Señal/efectos de los fármacos , Masculino , Especies Reactivas de Oxígeno/metabolismo , Exocitosis/fisiología , Exocitosis/efectos de los fármacos , Adenosina Difosfato/metabolismo , Adenosina Difosfato/farmacología , Calcio/metabolismo
11.
Crit Care ; 28(1): 29, 2024 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-38254226

RESUMEN

BACKGROUND: Sepsis is a life-threatening syndrome characterized by acute loss of organ function due to infection. Sepsis survivors are at risk for long-term comorbidities, have a reduced Quality of Life (QoL), and are prone to increased long-term mortality. The societal impact of sepsis includes its disease burden and indirect economic costs. However, these societal costs of sepsis are not fully understood. This study assessed sepsis's disease-related and indirect economic costs in the Netherlands. METHODS: Sepsis prevalence, incidence, sepsis-related mortality, hospitalizations, life expectancy, QoL population norms, QoL reduction after sepsis, and healthcare use post-sepsis were obtained from previous literature and Statistics Netherlands. We used these data to estimate annual Quality-adjusted Life Years (QALYs), productivity loss, and increase in healthcare use post-sepsis. A sensitivity analysis was performed to analyze the burden and indirect economic costs of sepsis under alternative assumptions, resulting in a baseline, low, and high estimated burden. The results are presented as a baseline (low-high burden) estimate. RESULTS: The annual disease burden of sepsis is approximately 57,304 (24,398-96,244; low-high burden) QALYs. Of this, mortality accounts for 26,898 (23,166-31,577) QALYs, QoL decrease post-sepsis accounts for 30,406 (1232-64,667) QALYs. The indirect economic burden, attributed to lost productivity and increased healthcare expenditure, is estimated at €416.1 (147.1-610.7) million utilizing the friction cost approach and €3.1 (0.4-5.7) billion using the human capital method. Cumulatively, the combined disease and indirect economic burdens range from €3.8 billion (friction method) to €6.5 billion (human capital method) annually within the Netherlands. CONCLUSIONS: Sepsis and its complications pose a substantial disease and indirect economic burden to the Netherlands, with an indirect economic burden due to production loss that is potentially larger than the burden due to coronary heart disease or stroke. Our results emphasize the need for future studies to prevent sepsis, saving downstream costs and decreasing the economic burden.


Asunto(s)
Calidad de Vida , Sepsis , Humanos , Países Bajos/epidemiología , Sepsis/epidemiología , Costo de Enfermedad , Hospitalización
12.
Phys Chem Chem Phys ; 26(13): 10336-10342, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38501209

RESUMEN

The stability of merocyanine forms formed under UV irradiation of a solution of a spiropyran salt, in which an organic part acts as a cation and a compact bromide ion as an anion, their photophysical properties, and the formation mechanism are studied in this work using time-dependent density functional theory. Theoretical calculations show that TTC and CTT are the most stable open forms (the difference in stability energies is 10.5 and 12.0 kcal mol-1 relative to the formation energy of spiropyran, respectively). The simulated absorption bands in the UV spectrum of the merocyanine forms are observed both in the UV region at 308-366 nm and in the visible region at 544-757 nm due to n → π* and π → π* type transitions. We found that the isomerisation mechanism of spiropyran into merocyanine forms includes two key stages: the ring opening to form cisoid merocyanine forms (except unstable TCC) through conical intersection and their subsequent isomerisation to form stable transoid isomers. The length of the Cspiro-O bond is 1.97 Å and the C1'-C2'-C3'-C4' angle is 70° in the structure close to conical intersection. The stage that determines the rate of this process is the isomerisation between transoid forms, as in the case of transformation of open merocyanine forms into spiropyran.

13.
Intern Med J ; 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38323357

RESUMEN

BACKGROUND: Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a rare autoimmune disease which is managed by a range of specialities. There are limited data on treatment practices in Australia and New Zealand. AIMS: To understand current patterns of acute AAV treatment in Australia and New Zealand. METHODS: An online survey was conducted between July and October 2022 investigating physicians' views on the management of AAV, focusing on induction therapy. The survey contained questions pertaining to access to treatment and responses to clinical management scenarios. Eosinophilic granulomatosis with polyangiitis was not included. A chi-squared test of independence was performed for statistical analysis. RESULTS: From a total of 55 responses, plasma exchange was difficult to access for 44% of respondents, more so in rural centres, and they also had difficulty accessing infusion centres. New Zealand clinicians had more difficulty accessing rituximab, with only 44% reporting easy access compared with Australian clinicians (93%). With clinical management scenarios, there was variation in the dosing regimen of glucocorticoids and initiation of plasma exchange, with 42% of respondents prescribing a glucocorticoid regimen different from the standard of care, the 'reduced-dose' arm of the Plasma Exchange and Glucocorticoids for the Treatment of ANCA-Associated Vasculitis trial. The choice of cyclophosphamide or rituximab for induction therapy was based on patient characteristics and medical history. CONCLUSIONS: There is substantial variation in approaches to the acute management of AAV in Australia and New Zealand, including differences in resource availability. This variation in care demonstrates the need to implement current practice guidelines and institute contemporary monitoring of AAV management, to achieve best patient outcomes.

14.
Am J Bioeth ; 24(6): 34-37, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38829600

RESUMEN

An adult university hospital ethics committee evaluated a proposed TA-NRP protocol in the fall of 2018. The protocol raised ethical concerns about violation of the Uniform Determination of Death Act and the prohibition known as the Dead Donor Rule, with potential resultant legal consequences. An additional concern was the potential for increased mistrust by the community of organ donation and transplantation. The ethics committee evaluated the responses to these concerns as unable to surmount the ethical and legal boundaries and the ethics committee declined to endorse the procedure. These concerns endure.


Asunto(s)
Comités de Ética , Perfusión , Obtención de Tejidos y Órganos , Humanos , Obtención de Tejidos y Órganos/ética , Donantes de Tejidos/ética , Muerte Encefálica , Trasplante de Órganos/ética , Trasplante de Órganos/legislación & jurisprudencia , Muerte
15.
Am J Bioeth ; 24(5): 11-24, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37220012

RESUMEN

Physicians generally recommend that patients resuscitated with naloxone after opioid overdose stay in the emergency department for a period of observation in order to prevent harm from delayed sequelae of opioid toxicity. Patients frequently refuse this period of observation despiteenefit to risk. Healthcare providers are thus confronted with the challenge of how best to protect the patient's interests while also respecting autonomy, including assessing whether the patient is making an autonomous choice to refuse care. Previous studies have shown that physicians have widely divergent approaches to navigating these conflicts. This paper reviews what is known about the effects of opioid use disorder on decision-making, and argues that some subset of these refusals are non-autonomous choices, even when patients appear to have decision making capacity. This conclusion has several implications for how physicians assess and respond to patients refusing medical recommendations after naloxone resuscitation.


Asunto(s)
Sobredosis de Opiáceos , Trastornos Relacionados con Opioides , Humanos , Naloxona , Analgésicos Opioides , Negativa del Paciente al Tratamiento
16.
Eur Spine J ; 33(2): 599-609, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37812256

RESUMEN

BACKGROUND: Proximal junctional kyphosis (PJK) is a complication following surgery for adult spinal deformity (ASD) possibly ameliorated by polymethyl methacrylate (PMMA) vertebroplasty of the upper instrumented vertebrae (UIV). This study quantifies PJK following surgical correction bridging the thoracolumbar junction ± PMMA vertebroplasty. METHODS: ASD patients from 2013 to 2020 were retrospectively reviewed and included with immediate postoperative radiographs and at least one follow-up radiograph. PMMA vertebroplasty at the UIV and UIV + 1 was performed at the surgeons' discretion. RESULTS: Of 102 patients, 56% received PMMA. PMMA patients were older (70 ± 8 vs. 66 ± 10, p = 0.021), more often female (89.3% vs. 68.2%, p = 0.005), and had more osteoporosis (26.8% vs. 9.1%, p = 0.013). 55.4% of PMMA patients developed PJK compared to 38.6% of controls (p = 0.097), and the rate of PJK development was not different between groups in univariate survival models. There was no difference in PJF (p > 0.084). Reoperation rates were 7.1% in PMMA versus 11.4% in controls (p = 0.501). In multivariable models, PJK development was not associated with the use of PMMA vertebroplasty (HR 0.77, 95% CI 0.38-1.60, p = 0.470), either when considered overall in the cohort or specifically in those with poor bone quality. PJK was significantly predicted by poor bone quality irrespective of PMMA use (HR 3.81, p < 0.001). CONCLUSIONS: In thoracolumbar fusions for adult spinal deformity, PMMA vertebroplasty was not associated with reduced PJK development, which was most highly associated with poor bone quality. Preoperative screening and management for osteoporosis is critical in achieving an optimal outcome for these complex operations. LEVEL OF EVIDENCE: 4, retrospective non-randomized case review.


Asunto(s)
Cifosis , Anomalías Musculoesqueléticas , Osteoporosis , Adulto , Humanos , Femenino , Polimetil Metacrilato/uso terapéutico , Estudios Retrospectivos , Cifosis/diagnóstico por imagen , Cifosis/cirugía , Columna Vertebral
17.
J Res Adolesc ; 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38561961

RESUMEN

Gains in holistic approaches to adult mental health have been associated with increasing interest in understanding psychological wellbeing (PWB) among adolescents. Empirical examination of measurement models for PWB in adolescence is lacking. Thus, the current study examined PWB in a longitudinal, diverse sample of 433 adolescents (non-Latinx Black: 37.6%; non-Latinx White: 25.9%; Latinx: 36.5%; Male adolescents: 50.1%). A one-factor, correlated six-factor and hierarchical models were examined across racial/ethnic (White, Black, and Hispanic) and gender (female, male) identities, after which the best fitting model was selected to undergo invariance testing. A one-factor structure was superior, and exhibited strict invariance across racial/ethnic and gender identities at each wave of the study, as well as longitudinal invariance within the entire sample.

18.
J Emerg Med ; 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38849254

RESUMEN

BACKGROUND: For many emergency physicians (EPs), deciding whether or not to allow a patient suffering the ill effects of opioid use to refuse care is the most frequent and fraught situation in which they encounter issues of decision-making capacity, informed refusal, and autonomy. Despite the frequency of this issue and the well-known impacts of opioid use disorder on decision-making, the medical ethics community has offered little targeted analysis or guidance regarding these situations. DISCUSSION: As a result, EPs demonstrate significant variability in how they evaluate and respond to them, with highly divergent understandings and application of concepts such as decision-making capacity, informed consent, autonomy, legal repercussions, and strategies to resolve the clinical dilemma. In this paper, we seek to provide more clarity to this issue for the EPs. CONCLUSIONS: Successfully navigating this issue requires that EPs understand the specific effects that opioid use disorder has on decision-making, and how that in turn bears on the ethical concepts of autonomy, capacity, and informed refusal. Understanding these concepts can lead to helpful strategies to resolve these commonly-encountered dilemmas.

19.
J Clin Psychol ; 80(2): 291-305, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37851207

RESUMEN

OBJECTIVE: Interventions in post-disaster environments may be accelerated by identifying protective behavioral factors adding incremental value to models of psychopathology using longitudinal methods. One protective behavior applicable to post-disaster contexts is behavioral activation (BA). BA is defined here as a behavioral pattern involving presence of valued activity engagement. While relevant post-disaster, the incremental value of BA behaviors in predicting longitudinal post-disaster outcomes is not well understood. We hypothesized that higher baseline engagement in behaviors consistent with a BA framework would predict decreased posttraumatic stress disorder (PTSD) symptom severity, depression symptom severity, and sleep disturbance approximately 3, 6, and 12 months after hurricane survivors completed baseline measures. METHODS: The current study is a secondary analysis from a randomized controlled trial of a disaster mental health digital intervention. Participants completed surveys at baseline and approximately 3, 6, and 12 months post-enrollment. Correlations and hierarchical regression analyses were calculated following data screening to predict PTSD symptom severity, depression symptom severity, and sleep disturbances. RESULTS: Controlling for alcohol use, prior trauma, displacement, and intervention condition, higher baseline BA consistently predicted less PTSD symptom severity, depression symptom severity, and sleep disturbances. CONCLUSION: Results suggest that post-disaster interventions should consider addressing BA. The study provides evidence that BA is potentially an important protective factor longitudinally predicting sleep disturbances and psychopathology after natural disasters.


Asunto(s)
Desastres , Trastornos por Estrés Postraumático , Humanos , Terapia Conductista , Salud Mental , Trastornos por Estrés Postraumático/psicología , Encuestas y Cuestionarios , Ensayos Clínicos Controlados Aleatorios como Asunto
20.
J Clin Ethics ; 35(1): 54-58, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38373333

RESUMEN

AbstractTo examine the ethical duty to patients and families in the setting of the resuscitation bay, we address a case with a focus on providing optimal care and communication to family members. We present a case of nonsurvivable traumatic injury in a minor, focusing on how allowing family more time at the bedside impacts the quality of death and what duty exists to maintain an emotionally optimal environment for family grieving and acceptance. Our analysis proposes tenets for patient and family-centric care that, in alignment with trauma-informed care principles, optimize the long-term well-being of the family, namely valuing family desires and sensitivity to location.


Asunto(s)
Bahías , Resucitación , Humanos , Resucitación/psicología , Familia/psicología
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