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1.
Nature ; 620(7974): 525-532, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37587297

RESUMEN

Interactions among electrons create novel many-body quantum phases of matter with wavefunctions that reflect electronic correlation effects, broken symmetries and collective excitations. Many quantum phases have been discovered in magic-angle twisted bilayer graphene (MATBG), including correlated insulating1, unconventional superconducting2-5 and magnetic topological6-9 phases. The lack of microscopic information10,11 of possible broken symmetries has hampered our understanding of these phases12-17. Here we use high-resolution scanning tunnelling microscopy to study the wavefunctions of the correlated phases in MATBG. The squares of the wavefunctions of gapped phases, including those of the correlated insulating, pseudogap and superconducting phases, show distinct broken-symmetry patterns with a √3 × âˆš3 super-periodicity on the graphene atomic lattice that has a complex spatial dependence on the moiré scale. We introduce a symmetry-based analysis using a set of complex-valued local order parameters, which show intricate textures that distinguish the various correlated phases. We compare the observed quantum textures of the correlated insulators at fillings of ±2 electrons per moiré unit cell to those expected for proposed theoretical ground states. In typical MATBG devices, these textures closely match those of the proposed incommensurate Kekulé spiral order15, whereas in ultralow-strain samples, our data have local symmetries like those of a time-reversal symmetric intervalley coherent phase12. Moreover, the superconducting state of MATBG shows strong signatures of intervalley coherence, only distinguishable from those of the insulator with our phase-sensitive measurements.

2.
Nature ; 600(7888): 240-245, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34670267

RESUMEN

The emergence of superconductivity and correlated insulators in magic-angle twisted bilayer graphene (MATBG) has raised the intriguing possibility that its pairing mechanism is distinct from that of conventional superconductors1-4, as described by the Bardeen-Cooper-Schrieffer (BCS) theory. However, recent studies have shown that superconductivity persists even when Coulomb interactions are partially screened5,6. This suggests that pairing in MATBG might be conventional in nature and a consequence of the large density of states of its flat bands. Here we combine tunnelling and Andreev reflection spectroscopy with a scanning tunnelling microscope to observe several key experimental signatures of unconventional superconductivity in MATBG. We show that the tunnelling spectra below the transition temperature Tc are inconsistent with those of a conventional s-wave superconductor, but rather resemble those of a nodal superconductor with an anisotropic pairing mechanism. We observe a large discrepancy between the tunnelling gap ΔT, which far exceeds the mean-field BCS ratio (with 2ΔT/kBTc ~ 25), and the gap ΔAR extracted from Andreev reflection spectroscopy (2ΔAR/kBTc ~ 6). The tunnelling gap persists even when superconductivity is suppressed, indicating its emergence from a pseudogap phase. Moreover, the pseudogap and superconductivity are both absent when MATBG is aligned with hexagonal boron nitride. These findings and other observations reported here provide a preponderance of evidence for a non-BCS mechanism for superconductivity in MATBG.

3.
Anal Chem ; 96(17): 6746-6755, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38632675

RESUMEN

Nonionic surfactant excipients (NISEs) are commonly added to biologics formulations to mitigate the effects of stress incurred by the active biotherapeutic during manufacturing, transport, and storage. During manufacturing, NISEs are added by dilution of a stock solution directly into a protein formulation, and their accurate addition is critical in maintaining the quality and integrity of the drug product and thus ensuring patient safety. This is especially true for the common NISEs, polysorbates 20 and 80 (PS20 and PS80, respectively) and poloxamer 188 (P188). With the increasing diversity of biologic modalities within modern pharmaceutical pipelines, there is thus a critical need to develop and deploy convenient and user-accessible analytical techniques that can rapidly and reliably quantify these NISEs under biopharmaceutically relevant conditions. We thus pursued 60 MHz benchtop quantitative NMR (qNMR) as a nondestructive and user-friendly analytical technique for the quantification of PS20, PS80, and P188 under such conditions. We demonstrated the ability of benchtop qNMR (1) to quantify simulated PS20, PS80, and P188 stock solutions representative of those used during the drug substance (DS) formulation step in biomanufacturing and (2) to quantify these NISEs at and below their target concentrations (≤0.025% w/v) directly in biologics formulations containing histidine, sucrose, and one of three biotherapeutic modalities (monoclonal antibody, antibody-drug conjugate, and Fc-fusion protein). Our results demonstrate that benchtop qNMR offers a fit-for-purpose, reliable, user-friendly, and green analytical route by which NISE of interest to the biopharmaceutical industry may be readily and reliably quantified. We conclude that benchtop qNMR has the potential to be applied to other excipient formulation components in the presence of various biological modalities as well as the potential for routine integration within analytical and QC laboratories across pharmaceutical development and manufacturing sites.


Asunto(s)
Excipientes , Espectroscopía de Resonancia Magnética , Tensoactivos , Tensoactivos/química , Excipientes/química , Excipientes/análisis , Espectroscopía de Resonancia Magnética/métodos , Polisorbatos/química , Poloxámero/química , Productos Biológicos/química , Productos Biológicos/análisis
4.
Brain Behav Immun ; 116: 160-174, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38070624

RESUMEN

Acute cerebral ischemia triggers a profound inflammatory response. While macrophages polarized to an M2-like phenotype clear debris and facilitate tissue repair, aberrant or prolonged macrophage activation is counterproductive to recovery. The inhibitory immune checkpoint Programmed Cell Death Protein 1 (PD-1) is upregulated on macrophage precursors (monocytes) in the blood after acute cerebrovascular injury. To investigate the therapeutic potential of PD-1 activation, we immunophenotyped circulating monocytes from patients and found that PD-1 expression was upregulated in the acute period after stroke. Murine studies using a temporary middle cerebral artery (MCA) occlusion (MCAO) model showed that intraperitoneal administration of soluble Programmed Death Ligand-1 (sPD-L1) significantly decreased brain edema and improved overall survival. Mice receiving sPD-L1 also had higher performance scores short-term, and more closely resembled sham animals on assessments of long-term functional recovery. These clinical and radiographic benefits were abrogated in global and myeloid-specific PD-1 knockout animals, confirming PD-1+ monocytes as the therapeutic target of sPD-L1. Single-cell RNA sequencing revealed that treatment skewed monocyte maturation to a non-classical Ly6Clo, CD43hi, PD-L1+ phenotype. These data support peripheral activation of PD-1 on inflammatory monocytes as a therapeutic strategy to treat neuroinflammation after acute ischemic stroke.


Asunto(s)
Edema Encefálico , Accidente Cerebrovascular Isquémico , Humanos , Ratones , Animales , Monocitos/metabolismo , Edema Encefálico/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Antígeno B7-H1/metabolismo , Infarto de la Arteria Cerebral Media/metabolismo
5.
Eur Radiol ; 34(4): 2394-2404, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37735276

RESUMEN

OBJECTIVE: To characterize the use and impact of radiation dose reduction techniques in actual practice for routine abdomen CT. METHODS: We retrospectively analyzed consecutive routine abdomen CT scans in adults from a large dose registry, contributed by 95 hospitals and imaging facilities. Grouping exams into deciles by, first, patient size, and second, size-adjusted dose length product (DLP), we summarized dose and technical parameters and estimated which parameters contributed most to between-protocols dose variation. Lastly, we modeled the total population dose if all protocols with mean size-adjusted DLP above 433 or 645 mGy-cm were reduced to these thresholds. RESULTS: A total of 748,846 CTs were performed using 1033 unique protocols. When sorted by patient size, patients with larger abdominal diameters had increased dose and effective mAs (milliampere seconds), even after adjusting for patient size. When sorted by size-adjusted dose, patients in the highest versus the lowest decile in size-adjusted DLP received 6.4 times the average dose (1680 vs 265 mGy-cm) even though diameter was no different (312 vs 309 mm). Effective mAs was 2.1-fold higher, unadjusted CTDIvol 2.9-fold, and phase 2.5-fold for patients in the highest versus lowest size-adjusted DLP decile. There was virtually no change in kV (kilovolt). Automatic exposure control was widely used to modulate mAs, whereas kV modulation was rare. Phase was the strongest driver of between-protocols variation. Broad adoption of optimized protocols could result in total population dose reductions of 18.6-40%. CONCLUSION: There are large variations in radiation doses for routine abdomen CT unrelated to patient size. Modification of kV and single-phase scanning could result in substantial dose reduction. CLINICAL RELEVANCE: Radiation dose-optimization techniques for routine abdomen CT are routinely under-utilized leading to higher doses than needed. Greater modification of technical parameters and number of phases could result in substantial reduction in radiation exposure to patients. KEY POINTS: • Based on an analysis of 748,846 routine abdomen CT scans in adults, radiation doses varied tremendously across patients of the same size and optimization techniques were routinely under-utilized. • The difference in observed dose was due to variation in technical parameters and phase count. Automatic exposure control was commonly used to modify effective mAs, whereas kV was rarely adjusted for patient size. Routine abdomen CT should be performed using a single phase, yet multi-phase was common. • kV modulation by patient size and restriction to a single phase for routine abdomen indications could result in substantial reduction in radiation doses using well-established dose optimization approaches.


Asunto(s)
Exposición a la Radiación , Tomografía Computarizada por Rayos X , Adulto , Humanos , Dosis de Radiación , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Abdomen
6.
Periodontol 2000 ; 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38647020

RESUMEN

Osseointegration is defined as the direct deposition of bone onto biomaterial devices, most commonly composed from titanium, for the purpose of anchoring dental prostheses. The use of autologous platelet concentrates (APC) has the potential to enhance this process by modifying the interface between the host and the surface of the titanium implant. The rationale is to modify the implant surface and implant-bone interface via "biomimicry," a process whereby the deposition of the host's own proteins and extracellular matrix enhances the biocompatibility of the implant and hence accelerates the osteogenic healing process. This review of the available evidence reporting on the effect of APC on osseointegration explores in vitro laboratory studies of the interaction of APC with different implant surfaces, as well as the in vivo and clinical effects of APC on osseointegration in animal and human studies. The inherent variability associated with using autologous products, namely the unique composition of each individual's blood plasma, as well as the great variety in APC protocols, combination of biomaterials, and clinical/therapeutic application, makes it is difficult to make any firm conclusions about the in vivo and clinical effects of APC on osseointegration. The available evidence suggests that the clinical benefits of adding PRP and the liquid form of L-PRF (liquid fibrinogen) to any implant surface appear to be limited. The application of L-PRF membranes in the osteotomy site, however, may produce positive clinical effects at the early stage of healing (up to 6 weeks), by promoting early implant stability and reducing marginal bone loss, although no positive longer term effects were observed. Careful interpretation and cautious conclusions should be drawn from these findings as there were various limitations in methodology. Future studies should focus on better understanding of the influence of APCs on the biomaterial surface and designing controlled preclinical and clinical studies using standardized APC preparation and application protocols.

7.
J Periodontal Res ; 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38758729

RESUMEN

Periodontitis is a chronic inflammatory disease caused by dysbiotic biofilms and destructive host immune responses. Extracellular vesicles (EVs) are circulating nanoparticles released by microbes and host cells involved in cell-to-cell communication, found in body biofluids, such as saliva and gingival crevicular fluid (GCF). EVs are mainly involved in cell-to-cell communication, and may hold promise for diagnostic and therapeutic purposes. Periodontal research has examined the potential involvement of bacterial- and host-cell-derived EVs in disease pathogenesis, diagnosis, and therapy, but data remains scarce on immune cell- or microbial-derived EVs. In this narrative review, we first provide an overview of the role of microbial and host-derived EVs on disease pathogenesis. Recent studies reveal that Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans-derived outer membrane vesicles (OMVs) can activate inflammatory cytokine release in host cells, while M1 macrophage EVs may contribute to bone loss. Additionally, we summarised current in vitro and pre-clinical research on the utilisation of immune cell and microbial-derived EVs as potential therapeutic tools in the context of periodontal treatment. Studies indicate that EVs from M2 macrophages and dendritic cells promote bone regeneration in animal models. While bacterial EVs remain underexplored for periodontal therapy, preliminary research suggests that P. gingivalis OMVs hold promise as vaccine candidates. Finally, we acknowledge the current limitations present in the field of translating immune cell derived EVs and microbial derived EVs in periodontology. It is concluded that microbial and host immune cell-derived EVs have a role in periodontitis pathogenesis and hence may be useful for studying disease pathophysiology, and as diagnostic and treatment monitoring biomarkers.

8.
BMC Biol ; 21(1): 219, 2023 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-37840141

RESUMEN

BACKGROUND: Social affinity and collective behavior are nearly ubiquitous in the animal kingdom, but many lineages feature evolutionarily asocial species. These solitary species may have evolved to conserve energy in food-sparse environments. However, the mechanism by which metabolic shifts regulate social affinity is not well investigated. RESULTS: In this study, we used the Mexican tetra (Astyanax mexicanus), which features riverine sighted surface (surface fish) and cave-dwelling populations (cavefish), to address the impact of metabolic shifts on asociality and other cave-associated behaviors in cavefish, including repetitive turning, sleeplessness, swimming longer distances, and enhanced foraging behavior. After 1 month of ketosis-inducing ketogenic diet feeding, asocial cavefish exhibited significantly higher social affinity, whereas social affinity regressed in cavefish fed the standard diet. The ketogenic diet also reduced repetitive turning and swimming in cavefish. No major behavioral shifts were found regarding sleeplessness and foraging behavior, suggesting that other evolved behaviors are not largely regulated by ketosis. We further examined the effects of the ketogenic diet via supplementation with exogenous ketone bodies, revealing that ketone bodies are pivotal molecules positively associated with social affinity. CONCLUSIONS: Our study indicated that fish that evolved to be asocial remain capable of exhibiting social affinity under ketosis, possibly linking the seasonal food availability and sociality.


Asunto(s)
Characidae , Cetosis , Trastornos del Inicio y del Mantenimiento del Sueño , Animales , Characidae/fisiología , Cuerpos Cetónicos , Evolución Biológica , Cuevas
9.
Subst Use Misuse ; 59(5): 643-650, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38115623

RESUMEN

Background: As of May 2023, 23 states and Washington, DC have legalized the sale of cannabis for adults aged 21+, and 38 states, three territories, and D.C. have legalized medical cannabis. Exposure to cannabis retailers could increase adolescent cannabis use. Few studies have examined the impact of residential proximity to cannabis retailers on adolescent cannabis use, and previous findings are inconsistent. Methods: This study examined associations between proximity to cannabis retailers and past 30-day cannabis use. Data were from Project Cal Teens, a statewide survey of California adolescents regarding cannabis-related opinions/behaviors (N = 1406, mean age = 15.5 years, 48% female, 38% Hispanic/Latinx, 33% White, 15% Asian/Pacific Islander, 10% Black/African American, 5% Other/Multiracial). Participants were recruited via schools/social media in 2018-2020. Results: For every additional 5 driving miles to the nearest cannabis retailer, the risk of past 30-day cannabis use was reduced by 3.6% [IRR: 0.964; 95% CI: 0.935-0.994]. For every additional 5 miles from a licensed retailer, the risk of past 30-day cannabis use was reduced by 4.3% [IRR: 0.957; 95% CI: 0.926-0.989]. Interaction analyses revealed that among Hispanic/Latinx students, every 5 miles from a licensed retailer was associated with an 11.9% reduction in the risk of past 30-day cannabis use [IRR: 0.881; 95% CI: 0.820-0.945]. Conclusions: As the number of cannabis retailers in the U.S. increases with the continued legalization of adult cannabis use, research examining the effects of these policies on underage use is crucial. Interventions could include enforcement of zoning laws in/near residential areas to reduce accessibility of adolescents to cannabis retailers.


Asunto(s)
Cannabis , Fumar Marihuana , Adolescente , Femenino , Humanos , Masculino , California/epidemiología , Marihuana Medicinal , Comercio , Fumar Marihuana/epidemiología , Características del Vecindario
10.
J Craniofac Surg ; 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38260961

RESUMEN

BACKGROUND AND OBJECTIVES: Ventricular shunting is one of the most common procedures in neurosurgery. However, complications and revisions are frequent. Patients requiring multiple revisions often suffer secondary issues with scalp healing over hardware. Many common ventricular shunt valves have an obligate thickness that creates a visible protrusion and can potentially cause local tissue ischemia and breakdown in the setting of repeated surgery. The authors present a simple technique for recessing the shunt valve into the underlying bone to alleviate protrusion in high-risk cases. Three example cases utilizing this technique are presented. METHODS: The skull directly underlying the planned valve site is uniformly recessed with a cutting burr several millimeters as desired while maintaining the inner cortical bone layer. The valve is fixed with standard cranial plating hardware. EXPECTED OUTCOMES: Three patients are reported who underwent shunt valve recession as an adjunct to their shunt revision with neuroplastic surgery assistance. All patients had undergone multiple prior surgeries that had resulted in thin and high-risk fragile scalp. In 1 patient, the prior valve was eroding through the scalp before the described revision. All patients had satisfactory cosmetic outcomes, and there were no revisions in the 2-month follow-up period. DISCUSSION: Complex and high-risk ventricular shunt patients should be considered for shunt valve recession into the bone to reduce wound-related complications and enhance healing. This is a technically simple, safe, and effective technique to include as a neuroplastic adjunct.

11.
Int J Mol Sci ; 25(3)2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38338647

RESUMEN

We aim to summarize the current evidence of Vascular endothelial growth factors (VEGF)s in external eye diseases and determine whether serum and plasma VEGF levels are associated with tear and ocular surface tissues. A systematic search of PUBMED and EMBASE was conducted using PRISMA guidelines between October 2022 and November 2023, with no restriction on language or publication date. Search terms included relevant MESH terms. These studies were evaluated for quality, and an assessment of the risk of bias was also carried out. Extracted data were then visually represented through relevant tables or figures. The initial literature search yielded 777 studies from PUBMED, 944 studies from EMBASE, and 10 studies from manual searches. Fourteen eligible studies were identified from 289 articles published from 2000 to 2023 in the English language or with English translations, including rabbit models, murine models, and human-derived samples. Most studies were retrospective in nature and case-control studies. Various common external eye diseases, such as dry eye disease (DED) and allergic eye disease were investigated. Despite limitations and small sample sizes, researchers have found elevated tissue levels of the VEGF in the vascularized cornea, especially in animal models, but there is no evidence of clear changes in the tear concentrations of VEGF in DED and allergic eye disease. Tear VEGF is associated with corneal vascularization. Anti-VEGF therapies may have the potential to manage such conditions.


Asunto(s)
Síndromes de Ojo Seco , Factor A de Crecimiento Endotelial Vascular , Humanos , Animales , Ratones , Conejos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Estudios Retrospectivos , Lágrimas/metabolismo , Factores de Crecimiento Endotelial Vascular/metabolismo , Síndromes de Ojo Seco/metabolismo
12.
Ophthalmology ; 130(6): 598-607, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36739981

RESUMEN

PURPOSE: To validate the prognostic usefulness of gene expression profile (GEP) testing in patients with uveal melanoma. To determine whether combining tumor size with the GEP classification provides additional prognostic value. DESIGN: Retrospective analysis. PARTICIPANTS: Patients with a diagnosis of choroidal melanoma examined at Yale New Haven Hospital; University of California, San Diego; and Memorial Sloan Kettering Cancer Center. METHODS: Patients' demographic and clinical data and tumor characteristics were collected. Univariate and multivariate Cox hazard regression analysis were used to assess the association between tumor characteristics and GEP classification with metastasis as an outcome. MAIN OUTCOME MEASURES: Metastasis-free survival (MFS). RESULTS: Of the 337 individuals included in the study, 87 demonstrated metastases. The mean follow-up time was 37.2 (standard deviation [SD], 40.2) months for patients with metastases and 55.0 (SD, 49.3) months for those without metastases. Tumors of larger thickness and GEP class 2 (vs. class 1) were associated significantly with increased risk of metastasis. Tumor thickness showed better prognostic usefulness than GEP classification (Wald statistic, 40.7 and 24.2, respectively). Class 2 tumors with a thickness of 7.0 mm or more were associated with increased risk of metastasis than tumors with a thickness of < 7.0 mm (hazard ratio [HR], 3.23; 95% confidence interval [CI], 1.61-6.51), whereas class 1 tumors with a thickness of 9.0 mm or more were associated with increased risk of metastasis than tumors with a thickness of < 9.0 mm (HR, 2.07; 95% CI, 0.86-4.99). No difference in MFS was found between patients with class 1A tumors compared with those with class 1B tumors (P = 0.8). Patients with class 2 tumors showed an observed 5-year MFS of 47.5% (95% CI, 36.0%-62.8%). CONCLUSIONS: Tumor size was the most significant predictor of metastasis and provided additional prognostic value independent of GEP classification. In addition, rates of metastasis for class 2 tumors were lower than estimates reported by Castle Bioscience, and no difference in rates of metastasis were found between class 1A and 1B tumors. This indicates that tumor size should be accounted for when relying on GEP for prognostication and that patients with GEP class 1A or 1B tumors may benefit from the same metastatic surveillance protocols. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.


Asunto(s)
Melanoma , Neoplasias de la Úvea , Humanos , Pronóstico , Estudios Retrospectivos , Melanoma/diagnóstico , Melanoma/genética , Melanoma/metabolismo , Neoplasias de la Úvea/diagnóstico , Neoplasias de la Úvea/genética , Neoplasias de la Úvea/patología , Perfilación de la Expresión Génica/métodos
13.
J Org Chem ; 88(19): 14012-14021, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37738112

RESUMEN

The installation of fluorine and fluorinated functional groups into drug-like scaffolds can perturb the physicochemical, pharmacokinetic, and pharmacodynamic properties of compounds. However, some potentially useful fluorinated substructures reside predominantly outside the realm of the current synthetic methodologies. One such substructure, the α,α-difluorophosphine oxide, might be convergently prepared by the reaction of a gem-difluorinated alkene with a P-H bond, though such nucleophilic reactions instead proceed through a C-F substitution pathway that delivers monofluorovinyl products. In contrast, we report a peroxide-initiated hydrophosphinylation reaction of gem-difluoroalkenes that avoids C-F substitution and produces a wide range of α,α-difluorophosphine oxides and functions using readily available reagents and green solvents.

14.
AJR Am J Roentgenol ; 221(3): 302-308, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37095660

RESUMEN

Artificial intelligence (AI) holds promise for helping patients access new and individualized health care pathways while increasing efficiencies for health care practitioners. Radiology has been at the forefront of this technology in medicine; many radiology practices are implementing and trialing AI-focused products. AI also holds great promise for reducing health disparities and promoting health equity. Radiology is ideally positioned to help reduce disparities given its central and critical role in patient care. The purposes of this article are to discuss the potential benefits and pitfalls of deploying AI algorithms in radiology, specifically highlighting the impact of AI on health equity; to explore ways to mitigate drivers of inequity; and to enhance pathways for creating better health care for all individuals, centering on a practical framework that helps radiologists address health equity during deployment of new tools.


Asunto(s)
Equidad en Salud , Radiología , Humanos , Inteligencia Artificial , Radiólogos , Radiología/métodos , Algoritmos
15.
Transpl Infect Dis ; 25(1): e13993, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36413505

RESUMEN

BACKGROUND: Reduction of immunosuppression (IS) upon detection of Polyomavirus (BK) viremia is widely used to prevent BK virus nephropathy. This retrospective case-control study assesses the frequency of de novo donor-specific antibodies (dnDSA) in renal transplant recipients with IS modulation due to BK viremia and the associated risk of antibody mediated rejection. METHODS: Our cohort included recipients of kidney transplantation between 2007 and 2017 with clinical, HLA antibody, and biopsy data. BK positivity was defined as viremia >10 000 c/ml or biopsy proven BK nephropathy. A total of 190 BK cases matched our inclusion criteria, each case was matched with two controls based on gender, donor type, and transplant within 1 year (N = 396). RESULTS: Despite lower number of HLA antigen mismatches (mean = 3.5 vs. 4.4, p < .001), dnDSA rates were higher in BK cases than in control group (22.1% vs. 13.9%, p = .02), with the majority detected following IS reduction for BK infection, and arising earlier posttransplant compared with no BK infection (294d vs. 434d, p < .001). Antibody mediated rejection rates were similar between cases and controls (8.9% and 8.3%, respectively), but rejection was more likely to occur earlier posttransplant in the BK cases (354d vs. 602d, p = .03). CONCLUSION: Our data suggest a link between IS reduction and the generation of dnDSA and/or rejection, supporting close monitoring for DSA in patients with reduced IS due to BK infection given their increased risk to develop dnDSA.


Asunto(s)
Virus BK , Trasplante de Riñón , Infecciones por Polyomavirus , Infecciones Tumorales por Virus , Humanos , Trasplante de Riñón/efectos adversos , Estudios Retrospectivos , Estudios de Casos y Controles , Viremia , Terapia de Inmunosupresión/efectos adversos , Receptores de Trasplantes , Rechazo de Injerto/prevención & control
16.
Crit Care ; 27(1): 440, 2023 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-37964311

RESUMEN

BACKGROUND: The mortality benefit of VV-ECMO in ARDS has been extensively studied, but the impact on long-term functional outcomes of survivors is poorly defined. We aimed to assess the association between ECMO and functional outcomes in a contemporaneous cohort of survivors of ARDS. METHODS: Multicenter retrospective cohort study of ARDS survivors who presented to follow-up clinic. The primary outcome was FVC% predicted. Univariate and multivariate regression models were used to evaluate the impact of ECMO on the primary outcome. RESULTS: This study enrolled 110 survivors of ARDS, 34 of whom were managed using ECMO. The ECMO cohort was younger (35 [28, 50] vs. 51 [44, 61] years old, p < 0.01), less likely to have COVID-19 (58% vs. 96%, p < 0.01), more severely ill based on the Sequential Organ Failure Assessment (SOFA) score (7 [5, 9] vs. 4 [3, 6], p < 0.01), dynamic lung compliance (15 mL/cmH20 [11, 20] vs. 27 mL/cmH20 [23, 35], p < 0.01), oxygenation index (26 [22, 33] vs. 9 [6, 11], p < 0.01), and their need for rescue modes of ventilation. ECMO patients had significantly longer lengths of hospitalization (46 [27, 62] vs. 16 [12, 31] days, p < 0.01) ICU stay (29 [19, 43] vs. 10 [5, 17] days, p < 0.01), and duration of mechanical ventilation (24 [14, 42] vs. 10 [7, 17] days, p < 0.01). Functional outcomes were similar in ECMO and non-ECMO patients. ECMO did not predict changes in lung function when adjusting for age, SOFA, COVID-19 status, or length of hospitalization. CONCLUSIONS: There were no significant differences in the FVC% predicted, or other markers of pulmonary, neurocognitive, or psychiatric functional recovery outcomes, when comparing a contemporaneous clinic-based cohort of survivors of ARDS managed with ECMO to those without ECMO.


Asunto(s)
COVID-19 , Oxigenación por Membrana Extracorpórea , Síndrome de Dificultad Respiratoria , Humanos , Persona de Mediana Edad , Resultado del Tratamiento , Estudios Retrospectivos , COVID-19/terapia , Sobrevivientes/psicología
17.
Curr Pain Headache Rep ; 27(9): 321-327, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37523121

RESUMEN

PURPOSE OF REVIEW: Peripheral nerve stimulation has seen a recent upsurge in utilization for various chronic pain conditions, specifically from a neuropathic etiology, where a single peripheral nerve can be pinpointed as a culprit for pain. RECENT FINDINGS: There is conflicting evidence about the efficacy and long-term outcomes of peripheral nerve stimulation for chronic pain, with most studies being small sized. The focus of this article is to review available evidence for the utilization of peripheral nerve stimulation for chronic pain syndromes as well as upcoming evidence in the immediate postoperative realm. The indications for the use of PNS have expanded from neuropathic pain such as occipital neuralgia and post-amputation pain, to more widespread disease processes such as chronic low back pain. Percutaneous PNS delivered over a 60-day period may provide significant carry-over effects including pain relief, potentially avoiding the need for a permanently implanted system while enabling improved function in patients with chronic pain.


Asunto(s)
Dolor Crónico , Terapia por Estimulación Eléctrica , Neuralgia , Estimulación Eléctrica Transcutánea del Nervio , Humanos , Dolor Crónico/terapia , Neuralgia/terapia , Manejo del Dolor , Enfermedad Crónica , Nervios Periféricos
18.
BMC Public Health ; 23(1): 1968, 2023 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-37821836

RESUMEN

BACKGROUND: Attitudes and behaviors towards mask wearing may influence the ability to reduce transmission of COVID-19 and other diseases. METHODS: University students, staff, and faculty (N = 9653) responded to an email invitation to complete electronic surveys (November 2021 and April 2022). Surveys included 19 items measuring attitudes and behaviors towards mask wearing from the Understanding America Study. Linear mixed models including variables for sex, age group, division, race and ethnicity, political affiliation, and history of COVID-19, were used to estimate the mean difference of the mean score for attitudes and behavior between Time 1 (November 2021) and Time 2 (April 2022). RESULTS: Participants were mostly female (62.1%), students (70.6%), White (39.5%) and Asian (34.7%). More than half identified their political affiliation as Democrat (65.5%). Characteristic variable-by-time interactions for difference in mean mask attitude scores difference were significant at Time 1 (T1) and Time 2 (T2) between Black and White participants (B = 0.18 (0.05), 95% CI: 0.07, 0.28, p = 0.001), Asian and White participants (B = 0.07 (0.02), 95% CI: 0.03-0.12, p = 0.001), participants with self-reported history of COVID-19 and no history of COVID-19 (B= -0.13 (0.02), 95% CI: -0.07, -0.18, p < 0.0001), females and males (B = 0.07 (0.02), 95% CI: 0.03, 0.11, p = 0.001), Republicans and Democrats (B= -0.18 (0.04), 95%CI: -0.26, -0.10, p < 0.0001) and Independents and Democrats (B= -0.10 (0.03), 95%CI: -0.15, -0.05, p < 0.0001). Mean difference in mean scores for mask behaviors at Time and Time 2 were significant between participants with COVID-19 and participants who did not have COVID-19 (B= -0.12 (0.04), 95% CI: -0.19, -0.04, p = 0.004), students compared to faculty and staff (B=-0.22 (0.05), -0.32, -0.12, p < 0.0001), between Republicans and Democrats (B-= -0.16 (0.07), 95% CI: -0.28, -0.03, p = 0.020, and between Independents and Democrats (B=-0.08 (0.04), 95% CI: -0.16, -0.002, p = 0.04). CONCLUSION: Race and ethnicity, political affiliation, and division may affect attitudes and behaviors in mask wearing. Further investigation into how characteristics influence public health measures such as mask wearing is needed to contain the spread of the COVID-19 virus, other infectious diseases, and future pandemics.


Asunto(s)
COVID-19 , Conocimientos, Actitudes y Práctica en Salud , Máscaras , Pandemias , Femenino , Humanos , Masculino , Asiático , COVID-19/epidemiología , COVID-19/prevención & control , Pandemias/prevención & control , SARS-CoV-2 , Autoinforme , Blanco , Control de Enfermedades Transmisibles/métodos , Negro o Afroamericano
19.
BMC Public Health ; 23(1): 601, 2023 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-36997945

RESUMEN

BACKGROUND: Mistrust in science and scientists may adversely influence the rate of COVID-19 vaccination and undermine public health initiatives to reduce virus transmission. METHODS: Students, staff and faculty responded to an email invitation to complete an electronic survey. Surveys included 21-items from the Trust in Science and Scientists Inventory questionnaire. Responses were coded so higher scores indicated a higher trust in science and scientists, A linear regression model including sex, age group, division, race and ethnicity, political affiliation, and history of COVID-19, was used to determine variables significantly associated with trust in science and scientists scores at the p < 0.05 level. RESULTS: Participants were mostly female (62.1%), Asian (34.7%) and White (39.5%) and students (70.6%). More than half identified their political affiliation as Democrat (65%). In the final regression model, all races and ethnicities had significantly lower mean trust in science and scientists scores than White participants [Black ([Formula: see text]= -0.42, 95% CI: -0.55, -0.43, p < 0.001); Asian ([Formula: see text]= -0.20, 95% CI: -0.24, -0.17, p < 0.001); Latinx ([Formula: see text]= -0.22, 95% CI: -0.27, -0.18, p < 0.001); Other ([Formula: see text]= -0.19, 95% CI: -0.26, -0.11, p < 0.001)]. Compared to those identifying as Democrat, all other political affiliations had significantly lower mean scores. [Republican ([Formula: see text] =-0.49, 95% CI: -0.55, -0.43, p < 0.0001); Independent ([Formula: see text] =-0.29, 95% CI: -0.33, -0.25, p < 0.0001); something else ([Formula: see text] =-0.19, 95% CI: -0.25, -0.12, p < 0.0001)]. Having had COVID-19 ([Formula: see text]= -0.10, 95% CI: -0.15, -0.06, p < 0.001) had significantly lower scores compared to those who did not have COVID-19. CONCLUSION: Despite the setting of a major research University, trust in science is highly variable. This study identifies characteristics that could be used to target and curate educational campaigns and university policies to address the COVID19 and future pandemics.


Asunto(s)
COVID-19 , Ciencia , Confianza , Femenino , Humanos , Masculino , COVID-19/epidemiología , Vacunas contra la COVID-19 , Docentes , Los Angeles , Pandemias , Estudiantes , Universidades
20.
Eur Spine J ; 32(7): 2326-2335, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37010611

RESUMEN

PURPOSE: To determine the optimal level for the measurement of psoas cross-sectional area and examine the correlation with short-term functional outcomes of posterior lumbar surgery. METHODS: Patients who underwent minimally invasive posterior lumbar surgery were included in this study. The cross-sectional area of psoas muscle was measured at each intervertebral level on T2-weighted axial images of preoperative MRI. Normalized total psoas area (NTPA) (mm2/m2) was calculated as total psoas area normalized to patient height. Intraclass Correlation Coefficient (ICC) was calculated for the analysis of inter-rater reliability. Patient reported outcome measures including Oswestry disability index (ODI), visual analog scale (VAS), short form health survey (SF-12) and patient-reported outcomes measurement information system were collected. A multivariate analysis was performed to elucidate independent predictors associated with failure to reach minimal clinically important difference (MCID) in each functional outcome at 6 months. RESULTS: The total of 212 patients were included in this study. ICC was highest at L3/4 [0.992 (95% CI: 0.987-0.994)] compared to the other levels [L1/2 0.983 (0.973-0.989), L2/3 0.991 (0.986-0.994), L4/5 0.928 (0.893-0.952)]. Postoperative PROMs were significantly worse in patients with low NTPA. Low NTPA was an independent predictor of failure to reach MCID in ODI (OR = 2.68; 95% CI: 1.26-5.67; p = 0.010) and VAS leg (OR = 2.43; 95% CI: 1.13-5.20; p = 0.022). CONCLUSION: Decreased psoas cross-sectional area on preoperative MRI correlated with functional outcomes after posterior lumbar surgery. NTPA was highly reliable, especially at L3/4.


Asunto(s)
Músculos Psoas , Fusión Vertebral , Humanos , Músculos Psoas/diagnóstico por imagen , Reproducibilidad de los Resultados , Procedimientos Quirúrgicos Mínimamente Invasivos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Región Lumbosacra , Fusión Vertebral/métodos , Resultado del Tratamiento , Estudios Retrospectivos
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