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1.
J Org Chem ; 89(11): 8120-8130, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38810272

RESUMEN

Herein, the execution of synthetic strategies solving scalability issues observed in the original route is reported, increasing the total yield by 50% compared to the previously disclosed synthesis. A notable restructuring of the route's initial steps to reach a common allylic alcohol intermediate employs a highly stereoselective epoxidation method and avoids superfluous protecting group manipulations while limiting dependence on kinetic resolution in establishing stereochemistry for four of the six chiral centers in (+)-desmethylxestospongin B. Different protecting group strategies to avoid problems with their subsequent removal were considered and enacted; to this end, material was retained as byproducts were suppressed. While the lactam semireduction under Birch conditions requires further investigation, the updated synthesis of (+)-desmethylxestospongin B reported here made it more scalable, affording 0.37 g of this natural product for continued biological studies.


Asunto(s)
Productos Biológicos , Estereoisomerismo , Estructura Molecular , Productos Biológicos/síntesis química , Productos Biológicos/química
2.
AIDS Behav ; 28(6): 1811-1821, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38493283

RESUMEN

The growing number of people aging with HIV represents a group vulnerable to the symptom burdens of HIV-associated neurocognitive disorder (HAND). Among younger groups, Mindfulness-Based Stress Reduction (MBSR) has been shown to help people living with HIV manage HIV-related and other life stress, and although there is some theoretical and empirical evidence that it may be effective among those with cognitive deficits, the approach has not been studied in older populations with HAND. Participants (n = 180) 55 years or older with HIV and cognitive impairment were randomly assigned to either an 8-week MBSR arm or a waitlist control. We assessed the impact of MBSR compared to a waitlist control on psychological outcomes [stress, anxiety, depression, and quality of life (QOL)] and cognitive metrics (e.g., speed of information processing, working memory, attention, impulsivity) measured at baseline, immediately post intervention (8 weeks) and one month later (16 weeks). Intent to treat analyses showed significant improvement in the MBSR group compared to control on symptoms of depression from baseline to 8 weeks, however, the difference was not sustained at 16 weeks. The MBSR group also showed improvement in perceived QOL from baseline to 16 weeks compared to the waitlist control group. Cognitive performance did not differ between the two treatment arms. MBSR shows promise as a tool to help alleviate the symptom burden of depression and low QOL in older individuals living with HAND and future work should address methods to better sustain the beneficial impact on depression and QOL.


Asunto(s)
Depresión , Infecciones por VIH , Atención Plena , Calidad de Vida , Estrés Psicológico , Humanos , Masculino , Femenino , Persona de Mediana Edad , Infecciones por VIH/psicología , Infecciones por VIH/complicaciones , Estrés Psicológico/terapia , Estrés Psicológico/psicología , Depresión/terapia , Depresión/psicología , Anciano , Resultado del Tratamiento , Ansiedad/psicología , Ansiedad/terapia , Disfunción Cognitiva/terapia , Disfunción Cognitiva/psicología
3.
Phys Chem Chem Phys ; 26(32): 21342-21356, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-38829308

RESUMEN

Molten salts play an important role in various energy-related applications such as high-temperature heat transfer fluids and reaction media. However, the extreme molten salt environment causes the degradation of materials, raising safety and sustainability challenges. A fundamental understanding of material-molten salt interfacial evolution is needed. This work studies the transformation of metallic Cr in molten 50/50 mol% KCl-MgCl2via multi-modal in situ synchrotron X-ray nano-tomography, diffraction and spectroscopy combined with density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulations. Notably, in addition to the dissolution of Cr in the molten salt to form porous structures, a δ-A15 Cr phase was found to gradually form as a result of the metal-salt interaction. This phase change of Cr is associated with a change in the coordination environment of Cr at the interface. DFT and AIMD simulations provide a basis for understanding the enhanced stability of δ-A15 Cr vs. bcc Cr, by revealing their competitive phase thermodynamics at elevated temperatures and probing the interfacial behavior of the molten salt at relevant facets. This study provides critical insights into the morphological and chemical evolution of metal-molten salt interfaces. The combination of multimodal synchrotron analysis and atomic simulation also offers an opportunity to explore a broader range of systems critical to energy applications.

4.
Appl Ergon ; 121: 104324, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39018706

RESUMEN

Industrial robots are increasingly commonplace, but research on prototypical accidents and injuries has been sparse, hindering evidence-based safety strategies. Using Severe Injury Reports (SIRs) from the U.S. Occupational Safety and Health Administration (OSHA), we identified 77 robot-related accidents from 2015-2022. Of these, 54 involved stationary robots, resulting in 66 injuries, mainly finger amputations and fractures to the head and torso. Mobile robots caused 23 accidents, leading to 27 injuries, mainly fractures to the legs and feet. A two-stage deductive-inductive thematic analysis was performed using text data from the final narratives in the reports to discover patterns in tasks, precipitating mechanisms, and contributing factors. Findings highlight the need for guards and collision avoidance systems that detect individual extremities. Post-contact strategies should focus on mitigating finger amputations. More structured and detailed narratives in the SIRs are needed.

5.
J Neurointerv Surg ; 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39084855

RESUMEN

Pediatric arteriovenous fistulas (PAVFs) are rare, representing only 7.3-17.2% of all pediatric shunts.1 2 In a number of cases they can lead to life-threatening venous hypertension, hydrocephalus and macrocrania,3 heart failure,1 hemorrhagic stroke,4 5 seizures,3 and cognitive developmental issues.1-3 In selected circumstances, early and aggressive treatment is recommended.We present two cases of single-connection, high-flow PAVFs. Case 1 represents a mid-basilar PAVF treated through a transarterial approach, while case 2 represents a quadrigeminal cistern PAVF treated with several transarterial sessions followed by a final transvenous session. The procedures are shown in video 1neurintsurg;jnis-2024-021955v1/V1F1V1Video 1 Clinical cases demonstrating endovascular treatment of pediatric pial arteriovenous fistulas.

6.
Bioengineering (Basel) ; 11(1)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38247931

RESUMEN

The corneal endothelium, comprising densely packed corneal endothelial cells (CECs) adhering to Descemet's membrane (DM), plays a critical role in maintaining corneal transparency by regulating water and ion movement. CECs have limited regenerative capacity within the body, and globally, there is a shortage of donor corneas to replace damaged corneal endothelia. The development of a carrier for cultured CECs may address this worldwide clinical need. In this study we successfully manufactured a gelatin nanofiber membrane (gelNF membrane) using electrospinning, followed by crosslinking with glutaraldehyde (GA). The fabricated gelNF membrane exhibited approximately 80% transparency compared with glass and maintained a thickness of 20 µm. The gelNF membrane demonstrated desirable permeability and degradability for a Descemet's membrane analog. Importantly, CECs cultured on the gelNF membrane at high densities showed no cytotoxic effects, and the expression of key CEC functional biomarkers was verified. To assess the potential of this gelNF membrane as a carrier for cultured CEC transplantation, we used it to conduct Descemet's membrane endothelial keratoplasty (DMEK) on rabbit eyes. The outcomes suggest this gelNF membrane holds promise as a suitable carrier for cultured CEC transplantation, offering advantages in terms of transparency, permeability, and sufficient mechanical properties required for successful transplantation.

7.
Artículo en Inglés | MEDLINE | ID: mdl-38913000

RESUMEN

This case report focuses on a rare presentation of Epstein-Barr virus as genital ulcers in a 14-year-old girl with no sexual activity history. Despite initial misdiagnosis and failed acyclovir treatment, investigations ruled out sexually transmitted causes but revealed elevated Epstein-Barr virus antibodies. Subsequent treatment with a 14-day prednisone course led to significant improvement. This case emphasizes the importance of considering nonsexual etiologies for genital ulcers to prevent delayed or inappropriate treatment and highlights the need for broader education on such atypical presentations.

8.
Clin Neurol Neurosurg ; 242: 108293, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38728853

RESUMEN

The November 2013 online publication of ARUBA, the first multi-institutional randomized controlled trial for unruptured brain arteriovenous malformations (AVMs), has sparked over 100 publications in protracted debates METHODS: This study sought to examine inpatient management patterns of brain AVMs from 2009 to 2016 and observe if changes in U.S. inpatient management were attributable to the ARUBA publication using interrupted time series of brain AVM studies from the National Inpatient Sample data 2009-2016. Outcomes of interest were use of embolization, surgery, combined embolization and microsurgery, radiotherapy, and observation during that admission. An interrupted time series design compared management trends before and after ARUBA. Segmented linear regression analysis tested for immediate and long-term impacts of ARUBA on management. RESULTS: Elective and asymptomatic patient admissions declined 2009-2016. In keeping with the ARUBA findings, observation for unruptured brain AVMs increased and microsurgery decreased. However, embolization, radiosurgery, and combined embolization and microsurgery also increased. For ruptured brain AVMs, treatment modality trends remained positive with even greater rates of observation, embolization, and combined embolization and microsurgery occurring after ARUBA (data on radiosurgery were scarce). None of the estimates for the change in trends were statistically significant. CONCLUSIONS: The publication of ARUBA was associated with a decrease in microsurgery and increase in observation for unruptured brain AVMs in the US. However, inpatient radiotherapy, embolization, and combined embolization and surgery also increased, suggesting trends moved counter to ARUBA's conclusions. This analysis suggested that ARUBA had a small impact as clinicians rejected ARUBA's findings in managing unruptured brain AVMs.


Asunto(s)
Embolización Terapéutica , Análisis de Series de Tiempo Interrumpido , Malformaciones Arteriovenosas Intracraneales , Humanos , Malformaciones Arteriovenosas Intracraneales/terapia , Estados Unidos , Embolización Terapéutica/métodos , Femenino , Pacientes Internos , Microcirugia , Masculino , Radiocirugia/tendencias , Adulto , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos , Ensayos Clínicos Controlados Aleatorios como Asunto
9.
Blood Adv ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38776400

RESUMEN

Socioeconomic status (SES) and race/ethnicity have been associated with outcomes of allogeneic hematopoietic cell transplantation (allo-HCT). Certain aspects of GVHD management such as the need for long term care, prolonged immunosuppressive treatment, and need for close follow up for complications may exacerbate disparities. Adults (≥ 18 years) reported to the Center for International Blood and Marrow Transplant Research (CIBMTR) who underwent a first alloHCT for acute leukemia, myelodysplastic syndrome, or myeloproliferative neoplasm between 2008 - 2018 were included. Endpoints for those developing GVHD included overall survival (OS), transplant related mortality (TRM), and disease relapse. Models were adjusted for patient and transplant related variables. A two-sided p-value < 0.01 was considered significant. Among the 14,825 allo-HCT recipients, 6,259 (42.2%) and 6,675 (45.0%) patients developed aGVHD and cGVHD, respectively. In patients with aGVHD, non-Hispanic Blacks had increased TRM (HR 1.50, 95% CI 1.24-1.83, p=0.0001) and overall mortality (HR 1.31, 1.14-1.50, p=0.0002) compared with non-Hispanic Whites, an association that disappeared when severity of aGVHD was included in the model. Lower SES was associated with increased risk of disease relapse (p=0.0016) but not OS or TRM. In patients who developed cGVHD, race and ethnicity were not associated with OS, TRM and disease relapse. However, the highest quartile of annual household income (≥ $80,000) had improved OS (HR 0.77, 0.69-0.85, p<0.0001) and reduced TRM (HR 0.86, 0.67-0.87, p<0.0001) compared with lowest quartile, adjusting for race and ethnicity. Race/ethnicity and SES are associated with outcomes after GVHD. Optimizing health care resources available to low SES patients and strategies to minimize the risk of severe GVHD in non-Hispanic Blacks may improve long-term outcomes.

10.
Artículo en Inglés | MEDLINE | ID: mdl-39150963

RESUMEN

Molten salts serve as effective high-temperature heat transfer fluids and thermal storage media used in a wide range of energy generation and storage facilities, including concentrated solar power plants, molten salt reactors and high-temperature batteries. However, at the salt-metal interfaces, a complex interplay of charge-transfer reactions involving various metal ions, generated either as fission products or through corrosion of structural materials, takes place. Simultaneously, there is a mass transport of ions or atoms within the molten salt and the parent alloys. The precise physical and chemical mechanisms leading to the diverse morphological changes in these materials remain unclear. To address this knowledge gap, this work employed a combination of synchrotron X-ray nanotomography and electron microscopy to study the morphological and chemical evolution of Ni-20Cr in molten KCl-MgCl2, while considering the influence of metal ions (Ni2+, Ce3+, and Eu3+) and variations in salt composition. Our research suggests that the interplay between interfacial diffusivity and reactivity determines the morphological evolution. The summary of the associated mass transport and reaction processes presented in this work is a step forward toward achieving a fundamental comprehension of the interactions between molten salts and alloys. Overall, the findings offer valuable insights for predicting the diverse chemical and structural alterations experienced by alloys in molten salt environments, thus aiding in the development of protective strategies for future applications involving molten salts.

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