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1.
Cureus ; 16(5): e59810, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38846219

RESUMEN

Gastric leiomyomas are benign, submucosal tumors found incidentally on unrelated imaging or during autopsy. The majority of leiomyomas are asymptomatic; however, patients can develop central ulcerations on the lesions leading to upper gastrointestinal (GI) bleeding. A 75-year-old female, with a past medical history of hypertension, hyperlipidemia, and a cerebrovascular accident, presented with complaints of melena, near-syncope events, lightheadedness, weakness, and hematemesis. A computed tomography (CT) of the abdomen with contrast found a heterogeneous low-attenuation mass of 4×4×3 cm3 within the gastric fundus and near the gastroesophageal (GE) junction. After an open gastrostomy and excisional biopsy, the mass was identified as a leiomyoma. This case report reviews the presentation, diagnostic assessments, and treatment of a gastric leiomyoma in a complex location proximal to the gastroesophageal junction. Gastric leiomyomas should be considered as a differential diagnosis for patients presenting with an upper gastrointestinal bleed.

3.
Nat Commun ; 15(1): 201, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172106

RESUMEN

Superfluid 3He is a paradigm for odd-parity Cooper pairing, ranging from neutron stars to uranium-based superconducting compounds. Recently it has been shown that 3He, imbibed in anisotropic silica aerogel with either positive or negative strain, preferentially selects either the chiral A-phase or the time-reversal-symmetric B-phase. This control over basic order parameter symmetry provides a useful model for understanding imperfect unconventional superconductors. For both phases, the orbital quantization axis is fixed by the direction of strain. Unexpectedly, at a specific temperature Tx, the orbital axis flops by 90∘, but in reverse order for A and B-phases. Aided by diffusion limited cluster aggregation simulations of anisotropic aerogel and small angle X-ray measurements, we are able to classify these aerogels as either "planar" and "nematic" concluding that the orbital-flop is caused by competition between short and long range structures in these aerogels.

4.
Spine (Phila Pa 1976) ; 49(2): 128-137, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-37612890

RESUMEN

STUDY DESIGN: Retrospective study with epidemiologic analysis of public Medicare data. OBJECTIVE: This study seeks to utilize geospatial analysis to identify distinct trends in lumbar fusion incidence and techniques in Medicare populations. SUMMARY OF BACKGROUND DATA: With an aging population and new technologies, lumbar fusion is an increasingly common procedure. There is controversy, however, regarding which indications and techniques achieve optimal outcomes, leading to significant intersurgeon variation and potential national disparities in care. MATERIALS AND METHODS: Medicare billing datasets were supplemented with Census Bureau socioeconomic data from 2013 to 2020. These databases listed lumbar fusions billed to Medicare by location, specialty, and technique. Hotspots and coldspots of lumbar fusion incidence and technique choice were identified with county-level analysis and compared with Mann-Whitney U . A linear regression of fusion incidence and a logistic regression of lumbar fusion hotspots/coldspots were also calculated. RESULTS: Between 2013 and 2020, 624,850 lumbar fusions were billed to Medicare. Lumbar fusion hotspots performed fusions at nearly five times the incidence of coldspots (101.6-21.1 fusions per 100,000 Medicare members) and were located in the Midwest, Colorado, and Virginia while coldspots were in California, Florida, Wisconsin, and the Northeast. Posterior and posterolateral fusion were the most favored techniques, with hotspots in the Northeast. Combined posterior and posterolateral fusion and posterior interbody fusion was the second most favored technique, predominantly in Illinois, Missouri, Arkansas, and Colorado. CONCLUSIONS: The geographic distribution of lumbar fusions correlates with variations in residency training, fellowship, and specialty. The geospatial patterning in both utilization and technique reflects a lack of consensus in the application of lumbar fusion. The strong variance in utilization is a potentially worrying finding that could suggest that the nonstandardization of lumbar fusion indication has led to both overtreatment and undertreatment across the nation. LEVEL OF EVIDENCE: Level 3-retrospective.


Asunto(s)
Medicare , Fusión Vertebral , Anciano , Humanos , Estados Unidos , Estudios Retrospectivos , Incidencia , Fusión Vertebral/métodos , Vértebras Lumbares/cirugía
5.
Ann Otol Rhinol Laryngol ; 133(2): 239-243, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37534717

RESUMEN

OBJECTIVES: To report a case of a 71-year-old woman who presented 8 years following 2 endoscopic brow lift procedures for evaluation of bony irregularities of her frontoparietal skull. To highlight a novel complication of Endotine fixation following an endoscopic brow lift procedure. METHODS: A chart review, bicoronal cranioplasty and a review of literature. RESULTS: The patient was satisfied with her post-surgical outcome and no complications were observed at the 1-month follow-up visit. A review of the literature revealed no previous reports of focal skull osteolysis relating to Endotine implants. CONCLUSION: We believe that our patient's focal calvarial osteolysis is a direct complication of Endotine fixation. Future research into the long-term effects of endoscopic brow lift procedures using Endotine implants is necessary to help ensure patient safety and guide future practices.


Asunto(s)
Osteólisis , Ritidoplastia , Humanos , Femenino , Anciano , Osteólisis/etiología , Osteólisis/cirugía , Cejas , Ritidoplastia/métodos , Endoscopía , Cráneo/cirugía
6.
Ann Vasc Surg ; 91: 36-49, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36603707

RESUMEN

BACKGROUND: The risk of spinal cord ischemia (SCI) with aortic aneurysm repair can cause significant neurological morbidity. Prevention of SCI is critical. We sought to identify risk factors that predispose to SCI that may guide strategies to mitigate the occurrence of SCI during and following these procedures. METHODS: This study includes all adults who underwent atraumatic, unruptured, thoracic, and suprarenal aortic aneurysm repairs (endovascular or open) at our institution over 11 years (2010-2020). Our database included patient demographics, aneurysm anatomic features, and operative characteristics and an extreme gradient boost (XGB) machine method was used to develop a predictive model for SCI. The model was trained on an 80% randomly stratified cohort of the data and tested on the remaining 20% testing cohort. Shapley values were used to determine the most important predictive factors of SCI and decision trees were used to identify risk factor threshold values and highest risk factor combinations. RESULTS: Information was collected for 174 adult patients undergoing thoracic and suprarenal aortic repair from 2010 to 2020. Fifty eight percent of the patients were male. Ninety seven (55.7%) patients had open aortic repair and 87 (44.3%) had endovascular repair. Twenty seven (15%) of all patients had major complications and were considered to have SCI. The XGB model converged over the training cohort with a testing cohort accuracy of 0.841 [Sensitivity = 75%, Specificity = 68%] and area under the curve of receiver operating characteristic of 0.774. The XGB model identified older age (> 65 years), history of neurologic disease, hyperlipidemia, diabetes, coronary artery disease, heart failure, poor renal function, < 6 months since last aortic repair, chronic anticoagulant use, preoperational anemia (Hemoglobin < 9), thrombocytopenia (platelet < 90,000), coagulopathy (prothrombin time > 15s and activated partial thromboplastin time > 40s), hypotension (mean arterial pressure < 70 mm Hg), longer operations (> 100 min), aneurysms longer than 5 cm, and anatomic location of aneurysm caudal to T-11 as risk factors for SCI in all types of aortic repair. Diabetic and heart failure patients undergoing longer operations (> 100 min) with thrombocytopenia or aneurysms longer than 5 cm were at the highest risk. CONCLUSIONS: The XGB model accurately identified risk factors of SCI with aortic aneurysm repair that may guide patient selection, timing of surgery, and strategies to minimize the risk of SCI.


Asunto(s)
Aneurisma de la Aorta Torácica , Aneurisma de la Aorta , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Isquemia de la Médula Espinal , Trombocitopenia , Adulto , Humanos , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/etiología , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/efectos adversos , Estudios Retrospectivos , Procedimientos Endovasculares/efectos adversos , Resultado del Tratamiento , Factores de Riesgo , Aneurisma de la Aorta/diagnóstico por imagen , Aneurisma de la Aorta/etiología , Aneurisma de la Aorta/cirugía , Isquemia de la Médula Espinal/diagnóstico , Isquemia de la Médula Espinal/etiología , Isquemia de la Médula Espinal/prevención & control , Aorta Abdominal/cirugía , Trombocitopenia/etiología
7.
World Neurosurg ; 171: 159-166.e13, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36529432

RESUMEN

BACKGROUND: The use of stents with various porosities for treating cerebral aneurysms requires dual antiplatelet therapy (DAPT) without clear guidelines on the utility of platelet function tests (PFTs) and the duration of DAPT. We sought to determine the effects of stent porosity, PFT usage, and DAPT duration on the radiographic and clinical outcomes after stenting of cerebral aneurysms. METHODS: PubMed was searched on March 29, 2021 for studies of cerebral aneurysm stenting that had specified the stent type and DAPT duration. A random effects meta-analysis was used to measure the prevalence of nonprocedural thrombotic and hemorrhagic events, clinical outcomes, aneurysm occlusion, and in-stent stenosis stratified by stent porosity, PFT usage, and DAPT duration. RESULTS: The review yielded 105 studies (89 retrospective and 16 prospective) with 117 stenting cohorts (50 high porosity, 17 intermediate porosity, and 50 low porosity). In the high-, intermediate-, and low-porosity stenting cohorts, PFT usage was 26.0%, 47.1%, and 62.0% and the mean DAPT duration was 3.51 ± 2.33, 3.97 ± 1.92, and 5.18 ± 2.27 months, respectively. The intermediate-porosity stents showed a reduced incidence of hemorrhagic events (π = 0.32%) compared with low-porosity stents (π = 1.36%; P = 0.01) and improved aneurysm occlusion (π = 6.18%) compared with high-porosity stents (π = 14.42%; P = 0.001) and low-porosity stents (π = 11.71%; P = 0.04). The prevalence of in-stent stenosis was lower for the intermediate-porosity (π = 0.57%) and high-porosity (π = 1.51%) stents than for the low-porosity stents (π = 3.30%; P < 0.05). PFT use had resulted in fewer poor clinical outcomes (π = 3.54%) compared with those without PFT use (π = 5.94%; P = 0.04). The DAPT duration had no effect on the outcomes. CONCLUSIONS: In the present meta-analysis, which had selected for studies of cerebral aneurysm stenting that had reported the DAPT duration, intermediate-porosity stents and PFT use had resulted significantly improved outcomes. No effect of DAPT duration could be detected.


Asunto(s)
Aneurisma Intracraneal , Inhibidores de Agregación Plaquetaria , Humanos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Aneurisma Intracraneal/tratamiento farmacológico , Porosidad , Estudios Retrospectivos , Estudios Prospectivos , Constricción Patológica/tratamiento farmacológico , Quimioterapia Combinada , Stents , Hemorragia/epidemiología
8.
J Homosex ; : 1-31, 2022 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-36250980

RESUMEN

Queerness and Catholicism have historically been at odds with one another. The Church's condemnation of queer individuals was pervasive globally for centuries, yet one way queerness and Catholicism converge is via Saint Sebastian depictions. The purpose of this research is to examine how and why Sebastian, a Catholic saint, has come to serve as an icon for the queer community as well as how dress has been used in depicting shifting representations of the Saint from the 15th to 21st centuries. Drawing upon the historic method, we critically analyze the meanings present in imagery of Saint Sebastian. Through our study of portrayals of the Saint, several key themes have emerged. Several of these contemporary artworks incorporated written language that reifies sainthood and associated suffering. Furthermore, many artworks' overall composition surrounding Saint Sebastian reinforced sainthood through contextual visual elements. Ambivalence in depictions of Saint Sebastian's fleshy body was apparent, with an emphasis on depicting Sebastian within the context of his executions. A gap in time periods and differing artwork styles was observed, with many of our examples being either from the Renaissance or post 1960s. Finally, many of the contemporary artworks surveyed included overt signifiers of queerness, with minimal references to subtle queerness.

9.
World Neurosurg ; 163: e59-e72, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35219917

RESUMEN

BACKGROUND: Intrathecal baclofen (ITB) is a treatment modality used to improve the quality of life of patients with intractable spasticity and dystonia. Although it is an effective solution in patients failing oral interventions, it is associated with potential infectious complications. It is known that pediatric patients with ITB have significantly higher infection rates compared with adult patients. The cause of these higher rates in pediatric patients remains unclear. In the present study, we performed a meta-analysis focusing on the incidence of infection, and clarification of potential risk factors for infection in pediatric patients with ITB. METHODS: This meta-analysis was performed in accordance with the PRISMA guidelines. An electronic database search was performed through PubMed, Web of Science, Embase, and Cochrane Library databases. Eligibility criteria and bias assessment were applied before statistical analysis. RESULTS: The 17 studies identified yielded 2238 pediatric patients treated with implanted ITB pumps between 1994 and 2014. Infection comprised 34% of observed complications, second only to catheter malfunction. Pediatric ITB primary infection ranged between 0% and 44% among included studies (interquartile range, 4.85%-18.85%). A linear mixed-effects regression model showed that subfascial implantation had 12% lower primary infection rates compared with subcutaneous implantations across the literature. The relative risk of infection was 56% lower in pediatric patients with subfascially implanted ITB pumps. CONCLUSIONS: Surgeons and clinicians should use these data to better assess patient risk-benefit when considering ITB pump implantation.


Asunto(s)
Baclofeno , Relajantes Musculares Centrales , Adulto , Niño , Humanos , Bombas de Infusión Implantables/efectos adversos , Inyecciones Espinales/efectos adversos , Espasticidad Muscular/tratamiento farmacológico , Espasticidad Muscular/etiología , Calidad de Vida , Estudios Retrospectivos
10.
J Neurosurg Case Lessons ; 1(21): CASE20168, 2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-35854865

RESUMEN

BACKGROUND: Hypertrophic cranial pachymeningitis is a rare inflammatory disorder characterized by thickening of the dura mater and multiple cranial neuropathies. Although an infectious etiology may be present, often no specific cause is discovered. OBSERVATIONS: The authors described a 71-year-old man with progressive right eye vision loss, ptosis, and complete ophthalmoplegia with imaging findings suggestive of hypertrophic cranial pachymeningitis. Extensive studies, including cerebrospinal fluid studies, showed negative results. Blood serum, cell-free evaluation, and paraffin-embedded dural tissue testing had positive results for Pseudomonas aeruginosa, which allowed treatment tailored to the organism and a salutary clinical outcome. LESSONS: The constellation of neurological and radiological findings may make a diagnosis difficult in an inflammatory setting. The most precise methodology for establishing a diagnosis involves sampling the dura and testing it for infectious pathology. However, if results are inconclusive, further cell-free serum sampling with next-generation sequencing is a viable option for identifying pathogens with infectious concerns. This case highlighted the importance of multimodality studies for identifying a targetable pathogen.

12.
World Neurosurg ; 126: 619-623, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30904800

RESUMEN

BACKGROUND: Central nervous system abscesses frequently can be seen in the immunocompromised population and most commonly consist of intracranial collections in the adult patient. Spinal intradural abscesses are less commonly encountered, and there are even fewer numbers in the pediatric population with a concordant absence of documentation in the published literature. CASE DESCRIPTION: In this case report, we describe the presentation of a 2-year-old boy with a history of perinatal Escherichia coli meningitis at 2.5 months of age who was found to have an intradural spinal lesion, initially concerning for neoplasm, but later confirmed as an E. coli abscess following biopsy. He was managed with surgical aspiration of the abscess and a long course of intravenous antibiotics. The patient was treated with antibiotics with repeat imaging studies that revealed residual abscess that required re-aspiration at a later date. CONCLUSIONS: Here we present an unusual disease process with an unusual disease pathogenesis in a pediatric patient currently residing in a developed country.


Asunto(s)
Absceso Epidural/diagnóstico , Infecciones por Escherichia coli/diagnóstico , Meningitis por Escherichia coli/complicaciones , Corticoesteroides/uso terapéutico , Antibacterianos/uso terapéutico , Terapia Combinada , Descompresión Quirúrgica , Diagnóstico Tardío , Diagnóstico Diferencial , Progresión de la Enfermedad , Drenaje , Absceso Epidural/tratamiento farmacológico , Absceso Epidural/microbiología , Absceso Epidural/cirugía , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/cirugía , Humanos , Recién Nacido , Laminectomía , Imagen por Resonancia Magnética , Neuroimagen , Modalidades de Fisioterapia , Compresión de la Médula Espinal/etiología , Neoplasias de la Columna Vertebral/diagnóstico , Siringomielia/diagnóstico
13.
BMJ Case Rep ; 20182018 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-30021731

RESUMEN

Myoepithelial tumours are a rare form of salivary gland neoplasm and intracranial metastases have rarely been described. The authors present the case of a 61-year-old patient with a history of primary myoepithelial carcinoma of the right foot. Metastases were found in the third ventricle, left temporal lobe and right frontal lobe. The third ventricular and left temporal lobe tumours were resected in a two-stage operation. Pathology of the third ventricular lesion was most consistent with metastasis. MRI of the spine 2 weeks after his operation revealed an intradural mass with several lesions in the lumbar thecal space suggesting further metastases. The patient succumbed to his disease 2 months after his two-stage operation and 5 years after his initial diagnosis. This appears to be the first case in the literature of multiple primary myoepithelial carcinoma metastases to the brain. Further information is needed to provide diagnostic and therapeutic recommendations.


Asunto(s)
Neoplasias Encefálicas/secundario , Carcinoma Mucoepidermoide/secundario , Mioepitelioma/secundario , Neoplasias de las Glándulas Salivales/patología , Biomarcadores de Tumor , Neoplasias Encefálicas/diagnóstico por imagen , Resultado Fatal , Humanos , Metástasis Linfática , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neoplasias de la Columna Vertebral/diagnóstico por imagen , Neoplasias de la Columna Vertebral/secundario
14.
Am Surg ; 84(6): 1027-1032, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29981643

RESUMEN

We hypothesize that higher elderly patient volume per trauma surgeon is associated with fewer clinical complications. This is a retrospective cohort study which included elderly patients admitted to trauma surgery service within a five-year period, from 2009 to 2013, at two Level I trauma centers in Florida. Trauma surgeons were stratified into three groups depending on patient volume. Primary outcomes were postinjury complications and in-hospital mortality, and secondary outcomes were hospital length of stay (LOS), intensive care unit LOS, and ventilator days. A total of 2379 elderly patients were included in this study. Elderly patient volume per surgeon did not significantly differ based on years in practice after fellowship (P = 0.88). The higher volume group had lower incidence of complications (15% complication rate, P = 0.02), compared with the average and low-volume group (18.1 and 21%, respectively), and had significantly lower rates of acute respiratory failure (P = 0.04) and acute renal failure (P = 0.004). In-hospital mortality was not affected by volume. Hospital LOS was decreased in the higher volume group (mean LOS 7.4 days, P < 0.001). There appears to be a relationship between elderly patient volume and outcome, independent of surgeon years of experience.


Asunto(s)
Complicaciones Posoperatorias/epidemiología , Heridas y Lesiones/complicaciones , Heridas y Lesiones/cirugía , Factores de Edad , Anciano , Anciano de 80 o más Años , Cuidados Críticos , Femenino , Florida , Mortalidad Hospitalaria , Humanos , Incidencia , Tiempo de Internación , Masculino , Persona de Mediana Edad , Pautas de la Práctica en Medicina/estadística & datos numéricos , Estudios Retrospectivos , Heridas y Lesiones/mortalidad
15.
Surg Obes Relat Dis ; 13(12): 1952-1956, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28943213

RESUMEN

BACKGROUND: Both hiatal hernias (HH) and morbid obesity significantly contribute to gastroesophageal reflux disease, which increases the risk for esophagitis and esophageal cancer. Therefore, concomitant HH repair is recommended during bariatric surgery procedures. Unfortunately, recurrence of HH after repair is not uncommon and the optimal surgical technique has yet to be established. OBJECTIVE: To evaluate the feasibility of recreating the phrenoesophageal ligaments by adding phrenoesophagopexy to HH repair during sleeve gastrectomy. SETTING: Independent, university-affiliated teaching hospital. METHODS: Retrospective chart review of all patients with a body mass index ≥35 kg/m2 who underwent a combined sleeve gastrectomy and HH repair between January 2010 and December 2014 by a single surgeon at a single institution. Demographic data and 30-day postoperative complications rates were obtained. RESULTS: There were 106 patients evaluated. Mean age was 50.8 ± 12.5 years, mean body mass index was 45.8 ± 7.1 kg/m2, and 87% were female. Mean operative time was 112 ± 24.5 minutes, and mean length of stay was 1.9 ± .7 days. The 30-day complication rate was .94% (1 gastric sleeve leak) and there were no deaths. Six patients (5.7%) required emergency department evaluation, and 5 (4.7%) required readmission for abdominal pain (2), dysphagia/dehydration (1), esophagitis (1), or gastric sleeve leak (1), which required reoperation. CONCLUSION: The addition of an interrupted phrenoesophagopexy for HH repair during sleeve gastrectomy appears to be a feasible technique with low 30-day morbidity and mortality rates. Long-term follow-up is needed to evaluate the efficacy in reducing HH recurrence rates.


Asunto(s)
Esófago/cirugía , Gastrectomía , Reflujo Gastroesofágico/cirugía , Hernia Hiatal/cirugía , Herniorrafia , Obesidad Mórbida/cirugía , Adulto , Estudios de Factibilidad , Femenino , Reflujo Gastroesofágico/etiología , Hernia Hiatal/etiología , Humanos , Masculino , Persona de Mediana Edad , Obesidad Mórbida/complicaciones , Estudios Retrospectivos , Resultado del Tratamiento
16.
Am Surg ; 83(6): 547-553, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28637554

RESUMEN

With a considerably increasing elderly population, we sought to determine whether the volume of elderly trauma patients treated impacted outcomes at two different Level I trauma centers. This is a retrospective review of all elderly patients (>60 years) at two state-verified Level I trauma centers over the past five years. The elderly trauma center (ETC) saw a greater proportion (52%) of elderly patients than the reference trauma center (30%, TC). Demographic and clinical characteristics were abstracted and stratified into ETC and TC groups for comparison. Primary outcomes were overall postinjury complication and mortality rates, as well as death after major complication (failure to rescue). ETC patients were older (78.6 vs 70.5), more likely to be admitted with severe head injuries (head abbreviated injury score ≥ 3, 50.0% vs 32%), had a greater overall injury burden (injury severity score > 16 41.4% vs 21.1%), and required intensive care unit admission (81.3% vs 64%) than the TC group. Need for operative intervention, mechanism of injury, and comorbidities were similar between the two groups. Overall complications were higher in trauma patients admitted to the TC (21.9% vs 14.3%), as well as failure to rescue (4.0% vs 1.8%). Adjusting for confounding factors, ETC had significantly lower chance of developing a postinjury complication (adjusted odds ratios [AOR] = 0.4, 95% confidence interval [CI] = [0.3, 0.5]), failure to rescue (AOR = 0.3, 95% CI = [0.1, 0.5]), and overall mortality (AOR = 0.3, 95% CI = [0.2, 0.4]). Improved outcomes were demonstrated in the Level I center treating a higher proportion of elderly patients. Exact etiology of these benefits should be determined for quality improvement in care of the injured geriatric patient.


Asunto(s)
Envejecimiento , Mortalidad Hospitalaria , Centros Traumatológicos/estadística & datos numéricos , Heridas y Lesiones/epidemiología , Anciano , Anciano de 80 o más Años , Femenino , Geriatría , Mortalidad Hospitalaria/tendencias , Humanos , Puntaje de Gravedad del Traumatismo , Unidades de Cuidados Intensivos/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Centros Traumatológicos/tendencias , Estados Unidos/epidemiología , Heridas y Lesiones/diagnóstico , Heridas y Lesiones/terapia
17.
Nature ; 531(7596): 610-3, 2016 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-27001693

RESUMEN

Elements heavier than zinc are synthesized through the rapid (r) and slow (s) neutron-capture processes. The main site of production of the r-process elements (such as europium) has been debated for nearly 60 years. Initial studies of trends in chemical abundances in old Milky Way halo stars suggested that these elements are produced continually, in sites such as core-collapse supernovae. But evidence from the local Universe favours the idea that r-process production occurs mainly during rare events, such as neutron star mergers. The appearance of a plateau of europium abundance in some dwarf spheroidal galaxies has been suggested as evidence for rare r-process enrichment in the early Universe, but only under the assumption that no gas accretes into those dwarf galaxies; gas accretion favours continual r-process enrichment in these systems. Furthermore, the universal r-process pattern has not been cleanly identified in dwarf spheroidals. The smaller, chemically simpler, and more ancient ultrafaint dwarf galaxies assembled shortly after the first stars formed, and are ideal systems with which to study nucleosynthesis events such as the r-process. Reticulum II is one such galaxy. The abundances of non-neutron-capture elements in this galaxy (and others like it) are similar to those in other old stars. Here, we report that seven of the nine brightest stars in Reticulum II, observed with high-resolution spectroscopy, show strong enhancements in heavy neutron-capture elements, with abundances that follow the universal r-process pattern beyond barium. The enhancement seen in this 'r-process galaxy' is two to three orders of magnitude higher than that detected in any other ultrafaint dwarf galaxy. This implies that a single, rare event produced the r-process material in Reticulum II. The r-process yield and event rate are incompatible with the source being ordinary core-collapse supernovae, but consistent with other possible sources, such as neutron star mergers.

18.
J Surg Res ; 198(2): 482-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25972315

RESUMEN

BACKGROUND: In an expanding elderly population, traumatic brain injury (TBI) remains a significant cause of death and disability. Guidelines for management of TBI, according to the Brain Trauma Foundation (BTF), include intracranial pressure (ICP) monitoring. Whether ICP monitoring contributes to outcomes in the elderly patients with TBI has not been explored. METHODS: This is a retrospective study extracted from the National Trauma Database 2007-2008 research datasets. Patients were included if aged >55 y and they met BTF indications for ICP monitoring. Patients that had nonsurvivable injuries (any body region, abbreviated injury score = 6), were dead on arrival, had withdrawal of care, or length of stay <48 h were excluded. Outcomes were then stratified based on ICP monitoring. The primary outcomes were inhospital mortality and favorable discharge. Logistic regression was used to analyze the effect of ICP monitoring on outcomes. RESULTS: A total of 4437 patients were included with 11.2% having an ICP monitor placed. Patients requiring an ICP monitor were younger overall, more likely to present hypertensive, had higher injury severity, and more likely to require operative intervention. Median initial Glasgow coma scale (3) was similar between groups. Of those patients with ICP monitoring, overall mortality was significantly higher, and they were less likely to have favorable discharge status. Craniotomy itself was not associated with increased mortality (P = 0.450). CONCLUSIONS: Our findings suggest that the use of ICP monitoring according to BTF guidelines in elderly TBI patients does not provide outcomes superior to treatment without monitoring. The ideal group to benefit from ICP monitor placement remains to be elucidated.


Asunto(s)
Lesiones Encefálicas/fisiopatología , Presión Intracraneal , Monitoreo Fisiológico/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Lesiones Encefálicas/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico/mortalidad , Estudios Retrospectivos , Estados Unidos/epidemiología
19.
Elife ; 2: e01119, 2013 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-24368730

RESUMEN

Obesity produces a chronic inflammatory state involving the NFκB pathway, resulting in persistent elevation of the noncanonical IκB kinases IKKε and TBK1. In this study, we report that these kinases attenuate ß-adrenergic signaling in white adipose tissue. Treatment of 3T3-L1 adipocytes with specific inhibitors of these kinases restored ß-adrenergic signaling and lipolysis attenuated by TNFα and Poly (I:C). Conversely, overexpression of the kinases reduced induction of Ucp1, lipolysis, cAMP levels, and phosphorylation of hormone sensitive lipase in response to isoproterenol or forskolin. Noncanonical IKKs reduce catecholamine sensitivity by phosphorylating and activating the major adipocyte phosphodiesterase PDE3B. In vivo inhibition of these kinases by treatment of obese mice with the drug amlexanox reversed obesity-induced catecholamine resistance, and restored PKA signaling in response to injection of a ß-3 adrenergic agonist. These studies suggest that by reducing production of cAMP in adipocytes, IKKε and TBK1 may contribute to the repression of energy expenditure during obesity. DOI: http://dx.doi.org/10.7554/eLife.01119.001.


Asunto(s)
Adipocitos/enzimología , Tejido Adiposo Blanco/enzimología , Catecolaminas/metabolismo , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 3/metabolismo , Quinasa I-kappa B/metabolismo , Inflamación/enzimología , Obesidad/enzimología , Proteínas Serina-Treonina Quinasas/metabolismo , Células 3T3-L1 , Adipocitos/efectos de los fármacos , Tejido Adiposo Blanco/efectos de los fármacos , Agonistas de Receptores Adrenérgicos beta 3/farmacología , Aminopiridinas/farmacología , Animales , Células COS , Chlorocebus aethiops , AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 3/genética , Dioxoles/farmacología , Modelos Animales de Enfermedad , Metabolismo Energético , Activación Enzimática , Células HEK293 , Humanos , Quinasa I-kappa B/antagonistas & inhibidores , Quinasa I-kappa B/genética , Inflamación/genética , Canales Iónicos/metabolismo , Lipólisis , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Mitocondriales/metabolismo , Obesidad/genética , Fosforilación , Poli I-C/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/genética , Receptores Adrenérgicos beta/metabolismo , Transducción de Señal , Esterol Esterasa/metabolismo , Factores de Tiempo , Transfección , Factor de Necrosis Tumoral alfa/farmacología , Proteína Desacopladora 1
20.
Nature ; 464(7285): 72-5, 2010 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-20203604

RESUMEN

Current cosmological models indicate that the Milky Way's stellar halo was assembled from many smaller systems. On the basis of the apparent absence of the most metal-poor stars in present-day dwarf galaxies, recent studies claimed that the true Galactic building blocks must have been vastly different from the surviving dwarfs. The discovery of an extremely iron-poor star (S1020549) in the Sculptor dwarf galaxy based on a medium-resolution spectrum cast some doubt on this conclusion. Verification of the iron-deficiency, however, and measurements of additional elements, such as the alpha-element Mg, are necessary to demonstrate that the same type of stars produced the metals found in dwarf galaxies and the Galactic halo. Only then can dwarf galaxy stars be conclusively linked to early stellar halo assembly. Here we report high-resolution spectroscopic abundances for 11 elements in S1020549, confirming its iron abundance of less than 1/4,000th that of the Sun, and showing that the overall abundance pattern follows that seen in low-metallicity halo stars, including the alpha-elements. Such chemical similarity indicates that the systems destroyed to form the halo billions of years ago were not fundamentally different from the progenitors of present-day dwarfs, and suggests that the early chemical enrichment of all galaxies may be nearly identical.

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