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1.
Proc Natl Acad Sci U S A ; 120(33): e2303567120, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37556502

RESUMEN

Lipid nanoparticles (LNPs) are a potent delivery technology that have made it possible for the recent clinical breakthroughs in mRNA therapeutics and vaccines. A key challenge to the broader implementation of mRNA therapeutics and vaccines is the development of technology to produce precisely defined LNP formulations, with throughput that can scale from discovery to commercial manufacturing and meet the stringent manufacturing standards of the pharmaceutical industry. To address these challenges, we have developed a microfluidic chip that incorporates 1×, 10×, or 256× LNP-generating units that achieve scalable production rates of up to 17 L/h of precisely defined LNPs. Using these chips, we demonstrate that LNP physical properties and potency in vivo are unchanged as throughput is scaled. Our chips are fabricated out of silicon and glass substrates, which have excellent solvent compatibility, compatibility with pharmaceutical manufacturing, and can be fully reset and reused. SARS-CoV-2 mRNA-LNP vaccines formulated by our chips triggered potent antibody responses in a preclinical study. These results demonstrate the feasibility of directly translating microfluidic-generated LNPs to the scale necessary for commercial production.


Asunto(s)
COVID-19 , Nanopartículas , Humanos , SARS-CoV-2/genética , COVID-19/prevención & control , Liposomas , ARN Mensajero/genética
2.
Nano Lett ; 24(5): 1477-1486, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38259198

RESUMEN

Lipid nanoparticle (LNP)-mediated nucleic acid therapies, including mRNA protein replacement and gene editing therapies, hold great potential in treating neurological disorders including neurodegeneration, brain cancer, and stroke. However, delivering LNPs across the blood-brain barrier (BBB) after systemic administration remains underexplored. In this work, we engineered a high-throughput screening transwell platform for the BBB (HTS-BBB), specifically optimized for screening mRNA LNPs. Unlike most transwell assays, which only assess transport across an endothelial monolayer, HTS-BBB simultaneously measures LNP transport and mRNA transfection of the endothelial cells themselves. We then use HTS-BBB to screen a library of 14 LNPs made with structurally diverse ionizable lipids and demonstrate it is predictive of in vivo performance by validating lead candidates for mRNA delivery to the mouse brain after intravenous injection. Going forward, this platform could be used to screen large libraries of brain-targeted LNPs for a range of protein replacement and gene editing applications.


Asunto(s)
Barrera Hematoencefálica , Liposomas , Nanopartículas , Animales , Ratones , Barrera Hematoencefálica/metabolismo , Células Endoteliales/metabolismo , ARN Mensajero/genética , Lípidos , Transfección , ARN Interferente Pequeño/genética
3.
MAGMA ; 37(1): 101-113, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38071698

RESUMEN

OBJECTIVE: Conventional single-echo spin-echo T2 mapping used for liver iron quantification is too long for breath-holding. This study investigated a short TR (~100 ms) single-echo spin-echo T2 mapping technique wherein each image (corresponding to a single TE) could be acquired in ~17 s-short enough for a breath-hold. TE images were combined for T2 fitting. To avoid T1 bias, each TE acquisition incremented TR to maintain a constant TR-TE. MATERIALS AND METHODS: Experiments at 1.5T validated the technique's accuracy in phantoms, 9 healthy volunteers, and 5 iron overload patients. In phantoms and healthy volunteers, the technique was compared to the conventional approach of constant TR for all TEs. Iron overload results were compared to FerriScan. RESULTS: In phantoms, the constant TR-TE technique provided unbiased estimates of T2, while the conventional constant TR approach underestimated it. In healthy volunteers, there was no significant discrepancy at the 95% confidence level between constant TR-TE and reference T2 values, whereas there was for constant TR scans. In iron overload patients, there was a high correlation between constant TR-TE and FerriScan T2 values (r2 = 0.95), with a discrepancy of 0.6+/- 1.4 ms. DISCUSSION: The short-TR single-echo breath-hold spin-echo technique provided unbiased estimates of T2 in phantoms and livers.


Asunto(s)
Sobrecarga de Hierro , Hígado , Humanos , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Contencion de la Respiración , Hierro , Sobrecarga de Hierro/diagnóstico por imagen
4.
J Eur Acad Dermatol Venereol ; 38(2): 265-280, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37750484

RESUMEN

Generalized pustular psoriasis (GPP) is a rare, chronic, neutrophilic inflammatory skin disease characterized by episodes of widespread eruption of sterile, macroscopic pustules that can be accompanied by systemic inflammation and symptoms. A systematic literature review and narrative synthesis were conducted to determine the impact of GPP on patients' health-related quality of life (HRQoL) and patient-reported severity of symptoms and to compare its impact to patients with plaque psoriasis (plaque PsO). Searches were undertaken in Embase, MEDLINE and the Cochrane Library from 1 January 2002 to 15 September 2022. Screening was carried out by two reviewers independently. Outcome measures included generic (e.g. EQ-5D, SF-36) and dermatology-specific (e.g. DLQI) clinical outcome assessments, and other relevant patient-reported outcome measures (PROMs) (e.g. severity of pain measured by a numerical rating scale). Overall, 20 studies were found to be eligible for inclusion, of which seven also had data for plaque PsO. The DLQI was the most frequently reported outcome measure (16 out of 20 studies). When reported, mean DLQI (SD) scores varied from 5.7 (1.2) to 15.8 (9.6) across the studies, indicating a moderate to very large effect on HRQoL; the wide range of scores and large SDs were explained by the small population sizes (n ≤ 12 for all studies except two). Similar ranges and large SDs were also observed for other measures within individual studies. However, in general, people with GPP reported a greater impact of their skin condition on HRQoL, when compared to people with plaque PsO (i.e. higher DLQI scores) and higher severity for itch, pain and fatigue. This systematic review highlighted the need for studies with a larger population size, a better understanding of the impact of cutaneous and extracutaneous symptoms and comorbidities on HRQoL during and between GPP flares, and outcome measures specifically tailored to the unique symptoms and the natural course/history of GPP.


Asunto(s)
Dermatitis , Psoriasis , Enfermedades Cutáneas Vesiculoampollosas , Humanos , Calidad de Vida , Psoriasis/diagnóstico , Piel , Enfermedad Crónica , Dolor
5.
Proc Natl Acad Sci U S A ; 118(15)2021 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33833060

RESUMEN

Parkinson's disease is characterized by accumulation of α-synuclein (αSyn). Release of oligomeric/fibrillar αSyn from damaged neurons may potentiate neuronal death in part via microglial activation. Heretofore, it remained unknown if oligomeric/fibrillar αSyn could activate the nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) family pyrin domain-containing 3 (NLRP3) inflammasome in human microglia and whether anti-αSyn antibodies could prevent this effect. Here, we show that αSyn activates the NLRP3 inflammasome in human induced pluripotent stem cell (hiPSC)-derived microglia (hiMG) via dual stimulation involving Toll-like receptor 2 (TLR2) engagement and mitochondrial damage. In vitro, hiMG can be activated by mutant (A53T) αSyn secreted from hiPSC-derived A9-dopaminergic neurons. Surprisingly, αSyn-antibody complexes enhanced rather than suppressed inflammasome-mediated interleukin-1ß (IL-1ß) secretion, indicating these complexes are neuroinflammatory in a human context. A further increase in inflammation was observed with addition of oligomerized amyloid-ß peptide (Aß) and its cognate antibody. In vivo, engraftment of hiMG with αSyn in humanized mouse brain resulted in caspase-1 activation and neurotoxicity, which was exacerbated by αSyn antibody. These findings may have important implications for antibody therapies aimed at depleting misfolded/aggregated proteins from the human brain, as they may paradoxically trigger inflammation in human microglia.


Asunto(s)
Inflamasomas/metabolismo , Microglía/inmunología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Enfermedad de Parkinson/inmunología , alfa-Sinucleína/inmunología , Péptidos beta-Amiloides/inmunología , Anticuerpos/inmunología , Diferenciación Celular , Células Cultivadas , Humanos , Células Madre Pluripotentes Inducidas/citología , Microglía/citología , Receptor Toll-Like 2/metabolismo , alfa-Sinucleína/genética
6.
J Am Chem Soc ; 145(8): 4691-4706, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36789893

RESUMEN

Ionizable lipid nanoparticles (LNPs) are the most clinically advanced nonviral platform for mRNA delivery. While they have been explored for applications including vaccines and gene editing, LNPs have not been investigated for placental insufficiency during pregnancy. Placental insufficiency is caused by inadequate blood flow in the placenta, which results in increased maternal blood pressure and restricted fetal growth. Therefore, improving vasodilation in the placenta can benefit both maternal and fetal health. Here, we engineered ionizable LNPs for mRNA delivery to the placenta with applications in mediating placental vasodilation. We designed a library of ionizable lipids to formulate LNPs for mRNA delivery to placental cells and identified a lead LNP that enables in vivo mRNA delivery to trophoblasts, endothelial cells, and immune cells in the placenta. Delivery of this top LNP formulation encapsulated with VEGF-A mRNA engendered placental vasodilation, demonstrating the potential of mRNA LNPs for protein replacement therapy during pregnancy to treat placental disorders.


Asunto(s)
Nanopartículas , Insuficiencia Placentaria , Femenino , Embarazo , Humanos , Placenta/metabolismo , ARN Mensajero/metabolismo , Células Endoteliales/metabolismo , Lípidos , Nanopartículas/metabolismo , ARN Interferente Pequeño/genética
7.
J Am Chem Soc ; 144(22): 9926-9937, 2022 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-35616998

RESUMEN

The development of lipid nanoparticle (LNP) formulations for targeting the bone microenvironment holds significant potential for nucleic acid therapeutic applications including bone regeneration, cancer, and hematopoietic stem cell therapies. However, therapeutic delivery to bone remains a significant challenge due to several biological barriers, such as low blood flow in bone, blood-bone marrow barriers, and low affinity between drugs and bone minerals, which leads to unfavorable therapeutic dosages in the bone microenvironment. Here, we construct a series of bisphosphonate (BP) lipid-like materials possessing a high affinity for bone minerals, as a means to overcome biological barriers to deliver mRNA therapeutics efficiently to the bone microenvironment in vivo. Following in vitro screening of BP lipid-like materials formulated into LNPs, we identified a lead BP-LNP formulation, 490BP-C14, with enhanced mRNA expression and localization in the bone microenvironment of mice in vivo compared to 490-C14 LNPs in the absence of BPs. Moreover, BP-LNPs enhanced mRNA delivery and secretion of therapeutic bone morphogenetic protein-2 from the bone microenvironment upon intravenous administration. These results demonstrate the potential of BP-LNPs for delivery to the bone microenvironment, which could potentially be utilized for a range of mRNA therapeutic applications including regenerative medicine, protein replacement, and gene editing therapies.


Asunto(s)
Lípidos , Nanopartículas , Animales , Difosfonatos/farmacología , Liposomas , Ratones , ARN Mensajero/genética , ARN Interferente Pequeño/genética
8.
J Surg Oncol ; 125(3): 414-424, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34617590

RESUMEN

BACKGROUND AND OBJECTIVES: Few empiric studies evaluate the effects of regionalization on pancreatic cancer care. METHODS: We queried the National Cancer Database to identify patients undergoing pancreaticoduodenectomy for clinical stage I/II pancreatic adenocarcinoma between 2006 and 2015. Facilities were categorized by annual pancreatectomy volume. Textbook oncologic outcome was defined as a margin negative resection, appropriate lymph node assessment, no prolonged hospitalization, no 30-day readmission, no 90-day mortality, and timely receipt of adjuvant chemotherapy. Multivariable regression adjusted for comorbid disease, pathologic stage, and facility characteristics was used to evaluate the relationship between facility volume and textbook outcome. RESULTS: Sixteen thousand six hundred and two patients underwent pancreaticoduodenectomy; 3566 (21.5%) had a textbook outcome. Operations performed at high volume centers increased each year (45.8% in 2006 to 64.2% in 2015, p < 0.001) as did textbook outcome rates (14.3%-26.2%, p < 0.001). Surgical volume was associated with textbook outcome. High volume centers demonstrated higher unadjusted rates of textbook outcome (25.4% vs. 11.8% p < 0.01) and increased adjusted odds of textbook outcome relative to low volume centers (odds ratio: 2.39, [2.02, 2.85], p < 0.001). Textbook outcome was associated with improved overall survival independent of volume. CONCLUSIONS: Regionalization of care for pancreaticoduodenectomy to high volume centers is ongoing and is associated with improved quality of care.


Asunto(s)
Adenocarcinoma/cirugía , Pancreatectomía , Neoplasias Pancreáticas/cirugía , Pancreaticoduodenectomía , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Anciano , Bases de Datos Factuales , Femenino , Hospitalización , Hospitales de Alto Volumen , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Programas Médicos Regionales , Resultado del Tratamiento , Estados Unidos
9.
Mol Ther ; 29(2): 859-872, 2021 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-33128896

RESUMEN

Immunotherapies designed to treat neurodegenerative tauopathies that primarily engage extracellular tau may have limited efficacy as tau is primarily intracellular. We generated tau-targeting single-chain variable fragments (scFvs) and intrabodies (iBs) from the phosphorylated tau-specific antibodies CP13 and PHF1 and the pan-tau antibody Tau5. Recombinant adeno-associated virus (rAAV) was utilized to express these antibody fragments in homozygous JNPL3 P301L tau mice. Two iBs (CP13i, PHF1i) and one scFv (PHF1s) abrogated tau pathology and delayed time to severe hindlimb paralysis. In a second tauopathy model (rTg4510), CP13i and PHF1i reduced tau pathology, but cognate scFvs did not. These data demonstrate that (1) disease-modifying efficacy does not require antibody effector functions, (2) the intracellular targeting of tau with phosphorylated tau-specific iBs is more effective than extracellular targeting with the scFvs, and (3) robust effects on tau pathology before neurodegeneration only resulted in modest disease modification as assessed by delay of severe motor phenotype.


Asunto(s)
Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/terapia , Vías Secretoras/efectos de los fármacos , Anticuerpos de Cadena Única/farmacología , Proteínas tau/antagonistas & inhibidores , Animales , Terapia Combinada , Dependovirus/genética , Modelos Animales de Enfermedad , Terapia Genética , Vectores Genéticos/administración & dosificación , Vectores Genéticos/genética , Ratones , Ratones Transgénicos , Enfermedades Neurodegenerativas/etiología , Resultado del Tratamiento , Proteínas tau/metabolismo
10.
Anaesthesia ; 77(10): 1129-1136, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36089858

RESUMEN

The primary aim of this review was to identify, analyse and codify the prominence and nature of human factors and ergonomics within difficult airway management algorithms. A directed search across OVID Medline and PubMed databases was performed. All articles were screened for relevance to the research aims and according to predetermined exclusion criteria. We identified 26 published airway management algorithms. A coding framework was iteratively developed identifying human factors and ergonomic specific words and phrases based on the Systems Engineering Initiative for Patient Safety model. This framework was applied to the papers to delineate qualitative and quantitative results. Our results show that human factors are well represented within recent airway management guidelines. Human factors associated with work systems and processes featured more prominently than user and patient outcome measurement and adaption. Human factors are an evolving area in airway management and our results highlight that further considerations are necessary in further guideline development.


Asunto(s)
Manejo de la Vía Aérea , Ergonomía , Humanos , Prevalencia
11.
Anaesthesia ; 77(12): 1395-1415, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35977431

RESUMEN

Across multiple disciplines undertaking airway management globally, preventable episodes of unrecognised oesophageal intubation result in profound hypoxaemia, brain injury and death. These events occur in the hands of both inexperienced and experienced practitioners. Current evidence shows that unrecognised oesophageal intubation occurs sufficiently frequently to be a major concern and to merit a co-ordinated approach to address it. Harm from unrecognised oesophageal intubation is avoidable through reducing the rate of oesophageal intubation, combined with prompt detection and immediate action when it occurs. The detection of 'sustained exhaled carbon dioxide' using waveform capnography is the mainstay for excluding oesophageal placement of an intended tracheal tube. Tube removal should be the default response when sustained exhaled carbon dioxide cannot be detected. If default tube removal is considered dangerous, urgent exclusion of oesophageal intubation using valid alternative techniques is indicated, in parallel with evaluation of other causes of inability to detect carbon dioxide. The tube should be removed if timely restoration of sustained exhaled carbon dioxide cannot be achieved. In addition to technical interventions, strategies are required to address cognitive biases and the deterioration of individual and team performance in stressful situations, to which all practitioners are vulnerable. These guidelines provide recommendations for preventing unrecognised oesophageal intubation that are relevant to all airway practitioners independent of geography, clinical location, discipline or patient type.


Asunto(s)
Dióxido de Carbono , Intubación Intratraqueal , Humanos , Intubación Intratraqueal/métodos , Capnografía , Esófago , Manejo de la Vía Aérea
12.
Plant Dis ; 106(4): 1114-1121, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34752125

RESUMEN

A new and devastating disease, rapid ohia death (ROD), in Hawaii led to a state quarantine that regulates interisland transport of ohia wood and plant material to prevent spread of the causal pathogens. Heat treatments of ohia logs in commercial trade were considered for phytosanitary treatment. Vacuum steam (VS) was evaluated for its ability to eradicate the pathogens, Ceratocystis lukuohia and C. huliohia, in main stem logs from ROD-affected forest trees. Replicate loads of three debarked logs (24 to 43 cm in diameter, 1.7 to 2.0 m long) were VS treated at 56°C for 30 min (five loads) or 60°C for 60 min (four loads) at a sapwood depth equal to 70% of log radius. Percentage isolation of Ceratocystis from VS and ambient temperature logs before treatment and summarized by source tree ranged from 12 to 66% and 6 to 31% based on carrot baiting assays of tissue taken from outer and inner sapwood, respectively. No viable Ceratocystis was detected in sapwood locations for the 60°C/60 min schedule or inner locations for the 56°C/30 min schedule after treatment. Only one subsample (0.48%, n = 208) of the latter schedule treatment yielded Ceratocystis. Time needed for treatment ranged from 7.4 to 15 h for the 56°C/30 min schedule and from 8.6 to 19.2 h for the 60°C/60 min schedule. These results demonstrate that VS is an effective and efficient method for treating large-diameter ohia logs that mill owners and regulatory plant pathologists may consider for use in Hawaii.


Asunto(s)
Myrtaceae , Vapor , Ceratocystis , Vacio
13.
J Biol Chem ; 295(21): 7492-7500, 2020 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-32299910

RESUMEN

Severe congenital neutropenia (SCN) is characterized by a near absence of neutrophils, rendering individuals with this disorder vulnerable to recurrent life-threatening infections. The majority of SCN cases arise because of germline mutations in the gene elastase, neutrophil-expressed (ELANE) encoding the neutrophil granule serine protease neutrophil elastase. Treatment with a high dose of granulocyte colony-stimulating factor increases neutrophil production and reduces infection risk. How ELANE mutations produce SCN remains unknown. The currently proposed mechanism is that ELANE mutations promote protein misfolding, resulting in endoplasmic reticulum stress and activation of the unfolded protein response (UPR), triggering death of neutrophil precursors and resulting in neutropenia. Here we studied the ELANE mutation p.G185R, often associated with greater clinical severity (e.g. decreased responsiveness to granulocyte colony-stimulating factor and increased leukemogenesis). Using an inducible expression system, we observed that this ELANE mutation diminishes enzymatic activity and granulocytic differentiation without significantly affecting cell proliferation, cell death, or UPR induction in murine myeloblast 32D and human promyelocytic NB4 cells. Impaired differentiation was associated with decreased expression of genes encoding critical hematopoietic transcription factors (Gfi1, Cebpd, Cebpe, and Spi1), cell surface proteins (Csf3r and Gr1), and neutrophil granule proteins (Mpo and Elane). Together, these findings challenge the currently prevailing model that SCN results from mutant ELANE, which triggers endoplasmic reticulum stress, UPR, and apoptosis.


Asunto(s)
Síndromes Congénitos de Insuficiencia de la Médula Ósea , Regulación Enzimológica de la Expresión Génica , Granulocitos/enzimología , Elastasa de Leucocito , Mutación Missense , Neutropenia/congénito , Respuesta de Proteína Desplegada , Sustitución de Aminoácidos , Animales , Apoptosis , Línea Celular Tumoral , Síndromes Congénitos de Insuficiencia de la Médula Ósea/enzimología , Síndromes Congénitos de Insuficiencia de la Médula Ósea/genética , Estrés del Retículo Endoplásmico , Humanos , Elastasa de Leucocito/biosíntesis , Elastasa de Leucocito/genética , Ratones , Neutropenia/enzimología , Neutropenia/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
14.
J Neurosci Res ; 99(8): 1957-1972, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33844860

RESUMEN

Binge drinking is a common occurrence in the United States, but a high concentration of alcohol in the blood has been shown to have reinforcing and reciprocal effects on the neuroimmune system in both dependent and non-dependent scenarios. The first part of this study examined alcohol's effects on the astrocytic response in the central amygdala and basolateral amygdala (BLA) in a non-dependent model. C57BL/6J mice were given access to either ethanol, water, or sucrose during a "drinking in the dark" paradigm, and astrocyte number and astrogliosis were measured using immunohistochemistry. Results indicate that non-dependent consumption increased glial fibrillary acidic protein (GFAP) density but not the number of GFAP+ cells, suggesting that non-dependent ethanol is sufficient to elicit astrocyte activation. The second part of this study examined how astrocytes impacted behaviors and the neurochemistry related to alcohol using the chemogenetic tool, DREADDs (designer receptors exclusively activated by designer drugs). Transgenic GFAP-hM3Dq mice were administered clozapine N-oxide both peripherally, affecting the entire central nervous system (CNS), or directly into the BLA. In both instances, GFAP-Gq-signaling activation significantly reduced ethanol consumption and correlating blood ethanol concentrations. However, GFAP-Gq-DREADD activation throughout the CNS had more broad effects resulting in decreased locomotor activity and sucrose consumption. More targeted GFAP-Gq-signaling activation in the BLA only impacted ethanol consumption. Finally, a glutamate assay revealed that after GFAP-Gq-signaling activation glutamate concentrations in the amygdala were partially normalized to control levels. Altogether, these studies support the theory that astrocytes represent a viable target for alcohol use disorder therapies.


Asunto(s)
Astrocitos/metabolismo , Complejo Nuclear Basolateral/metabolismo , Consumo Excesivo de Bebidas Alcohólicas/metabolismo , Etanol/farmacología , Proteína Ácida Fibrilar de la Glía/metabolismo , Animales , Consumo Excesivo de Bebidas Alcohólicas/inmunología , Ácido Glutámico , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Actividad Motora/efectos de los fármacos
15.
Acta Neuropathol ; 141(3): 359-381, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33496840

RESUMEN

Accumulation of the tau protein in fibrillar intracellular aggregates is a defining feature of multiple neurodegenerative diseases collectively referred to as tauopathies. Despite intensive study of tau, there is limited information on the formation and clearance dynamics of tau inclusions. Using rAAV vectors to mediate expression of Dendra2-tagged human wild-type, P301L and pro-aggregant P301L/S320F tau proteins, with and without the addition of exogenous tau fibrillar seeds, we evaluated tau inclusion dynamics in organotypic brain slice culture (BSC) models using long-term optical pulse labeling methodology. Our studies reveal that tau inclusions typically form in 12-96 h in tauopathy BSC models. Unexpectedly, we demonstrate appreciable turnover of tau within inclusions with an average half-life of ~ 1 week when inclusions are newly formed. When BSCs with inclusions are aged in culture for extended periods, tau inclusions continue to turnover, but their half-lives increase to ~ 2 weeks and ~ 3 weeks after 1 and 2 months in culture, respectively. Individual tau inclusions can be long-lived structures that can persist for months in these BSC models and for even longer in the human brain. However, our data indicate that tau inclusions, are not 'tombstones', but dynamic structures with appreciable turnover. Understanding the cellular processes mediating this inclusion turnover may lead to new therapeutic strategies that could reverse pathological tau inclusion formation.


Asunto(s)
Encéfalo/metabolismo , Encéfalo/patología , Neuronas/metabolismo , Tauopatías/metabolismo , Proteínas tau/metabolismo , Animales , Humanos , Cuerpos de Inclusión/metabolismo , Cuerpos de Inclusión/patología , Ratones , Neuronas/patología , Técnicas de Cultivo de Órganos , Tauopatías/patología
16.
J Magn Reson Imaging ; 53(3): 827-837, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33135834

RESUMEN

BACKGROUND: Persons with hemophilia experience hemarthrosis, which can lead to cartilage degeneration, causing physical impairment. MRI T2 mapping has the potential to be used as a tool to evaluate early arthropathic changes and cartilage degeneration in patients with hemophilia. PURPOSE: To assess the value of MRI-T2 mapping as a tool for investigating the cartilage status of children and adolescents with hemophilic arthropathy. STUDY TYPE: Prospective, cross-sectional. SUBJECTS: Twenty-eight boys with hemophilia (aged 5-17 years) and 23 healthy boys (aged 7-17 years). FIELD STRENGTH/SEQUENCES: A multiecho spin-echo T2 -weighted gradient echo sequence was used on a 3.0T magnet. ASSESSMENT: MRI-T2 maps of ankle (tibia-talus) (n = 19) or knee (femur-tibia) (n = 9) cartilage were assessed in hemophilia and healthy groups. An anatomically-based MRI score was also assigned to each ankle/knee. STATISTICAL TESTS: Pearson's correlation coefficient (r), linear regression, intraclass correlation coefficient (ICC), and analysis of variance (ANOVA) test. RESULTS: Negative associations between age and ankle/knee cartilage T2 relaxation times were found in hemophilia (r = -0.72 [P = 0.03] to -0.55 [P = 0.01]) and healthy (r = -0.84 [P < 0.001] to -0.55 [P = 0.20]) groups. There were nonsignificant associations between ankle cartilage T2 relaxation times and MRI scores (r = -0.15 [P = 0.54] to 0.31 [P = 0.19]). DATA CONCLUSION: Results of this clinical investigation emphasize the potential importance of MRI-T2 maps as a tool to understand the functional status of cartilage in children and adolescents with hemophilic arthropathy, while holding promise for the detection of early cartilage degeneration prior to macroscopic characterization by conventional MRI. MRI-T2 mapping may provide novel information that is not reflected in the anatomically-based MRI scoring system. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2.


Asunto(s)
Cartílago Articular , Adolescente , Cartílago Articular/diagnóstico por imagen , Niño , Preescolar , Estudios Transversales , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Estudios Prospectivos
17.
J Surg Res ; 257: 349-355, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32892130

RESUMEN

BACKGROUND: Bile duct injury (BDI) during cholecystectomy requiring biliary enteric reconstruction (BER) is associated with increased risk of postoperative mortality and substantive increases in costs of care. The impact of the timing of repair on overall costs of care is poorly understood. MATERIALS AND METHODS: The Healthcare Cost and Utilization Project Florida State databases (2006-2015) were queried to identify patients undergoing BER within 1-y of cholecystectomy performed for benign biliary disease. Patients were then categorized by the time interval between cholecystectomy to BER: early (≤3 d), intermediate (4 d to 6 wk), or delayed (>6 wk). By repair timing strategy, 1-y outcomes were aggregated, including charges, inpatient costs, aggregate length of stay, and inpatient mortality. RESULTS: Of 563,887 patients undergoing cholecystectomy, 1168 required a BER (0.21%) within 1-y of cholecystectomy. Early BER was performed in 560 patients (47.9%), intermediate BER in 439 patients (37.6%), and delayed BER in 169 (14.5%) patients. On multivariable analysis adjusting for patient, procedure, and facility factors, intermediate BER demonstrated an increased risk of mortality (odds ratio 2.04, 95% confidence interval [CI]: 1.16-3.56) and increased aggregate inpatient cost (+$12,472; 95% CI: $6421-$18,524) relative to early BER. There was no notable difference in adjusted risk of inpatient mortality between the early and delayed BER cohorts (odds ratio 0.90; 95% CI: 0.32-1.25), but delayed BER was associated with increased aggregate inpatient costs (+$45,111; 95% CI: $36,813-$53,409). CONCLUSIONS: When compared with delayed BER, early repair was associated with shorter aggregate inpatient hospitalization without increased postoperative mortality. Intermediate timing of repair is associated with increased costs and risk of mortality.


Asunto(s)
Conductos Biliares/lesiones , Conductos Biliares/cirugía , Colecistectomía/efectos adversos , Tiempo de Tratamiento/economía , Anciano , Colecistectomía/economía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo
18.
PLoS Genet ; 14(9): e1007642, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30216339

RESUMEN

PAX5, one of nine members of the mammalian paired box (PAX) family of transcription factors, plays an important role in B cell development. Approximately one-third of individuals with pre-B acute lymphoblastic leukemia (ALL) acquire heterozygous inactivating mutations of PAX5 in malignant cells, and heterozygous germline loss-of-function PAX5 mutations cause autosomal dominant predisposition to ALL. At least in mice, Pax5 is required for pre-B cell maturation, and leukemic remission occurs when Pax5 expression is restored in a Pax5-deficient mouse model of ALL. Together, these observations indicate that PAX5 deficiency reversibly drives leukemogenesis. PAX5 and its two most closely related paralogs, PAX2 and PAX8, which are not mutated in ALL, exhibit overlapping expression and function redundantly during embryonic development. However, PAX5 alone is expressed in lymphocytes, while PAX2 and PAX8 are predominantly specific to kidney and thyroid, respectively. We show that forced expression of PAX2 or PAX8 complements PAX5 loss-of-function mutation in ALL cells as determined by modulation of PAX5 target genes, restoration of immunophenotypic and morphological differentiation, and, ultimately, reduction of replicative potential. Activation of PAX5 paralogs, PAX2 or PAX8, ordinarily silenced in lymphocytes, may therefore represent a novel approach for treating PAX5-deficient ALL. In pursuit of this strategy, we took advantage of the fact that, in kidney, PAX2 is upregulated by extracellular hyperosmolarity. We found that hyperosmolarity, at potentially clinically achievable levels, transcriptionally activates endogenous PAX2 in ALL cells via a mechanism dependent on NFAT5, a transcription factor coordinating response to hyperosmolarity. We also found that hyperosmolarity upregulates residual wild type PAX5 expression in ALL cells and modulates gene expression, including in PAX5-mutant primary ALL cells. These findings specifically demonstrate that osmosensing pathways may represent a new therapeutic target for ALL and more broadly point toward the possibility of using gene paralogs to rescue mutations driving cancer and other diseases.


Asunto(s)
Riñón/metabolismo , Osmorregulación , Factor de Transcripción PAX2/metabolismo , Factor de Transcripción PAX5/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Animales , Linfocitos B/metabolismo , Diferenciación Celular/genética , Línea Celular Tumoral , Técnicas de Cocultivo , Femenino , Células HEK293 , Humanos , Soluciones Hipertónicas/farmacología , Riñón/efectos de los fármacos , Masculino , Ratones , Mutación , Osmorregulación/efectos de los fármacos , Factor de Transcripción PAX2/genética , Factor de Transcripción PAX5/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Cultivo Primario de Células , ARN Interferente Pequeño/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
19.
J Integr Neurosci ; 20(4): 933-943, 2021 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-34997716

RESUMEN

Alcoholism causes various maladaptations in the central nervous system, including the neuroimmune system. Studies of alcohol-induced dysregulation of the neuroimmune system generally focus on alcohol dependence and brain damage, but our previous research indicates that repetitive binge-like consumption perturbs cytokines independent of cell death. This paper extends that research by examining the impact of binge-like consumption on microglia in the hippocampus and the amygdala. Microglia were assessed using immunohistochemistry following binge-like ethanol consumption based on Drinking-in-the-Dark model. Immunohistochemistry results showed that binge-like ethanol consumption caused an increase in Iba-1 immunoreactivity and the number of Iba-1+ cells after one Drinking-in-the-Dark cycle. However, after three Drinking-in-the-Dark cycles, the number of microglia decreased in the hippocampus. We showed that in the dentate gyrus, the average immunoreactivity/cell was increased following ethanol exposure despite the decrease in number after three cycles. Likewise, Ox-42, an indicator of microglia activation, was upregulated after ethanol consumption. No significant effects on microglia number or immunoreactivity (Iba-1 nor Ox-42) were observed in the amygdala. Finally, ethanol caused an increase in the expression of the microglial gene Aif-1 during intoxication and ten days into abstinence, suggesting persistence of ethanol-induced upregulation of microglial genes. Altogether, these findings indicate that repetitive binge-like ethanol is sufficient to elicit changes in microglial reactivity. This altered neuroimmune state may contribute to the development of alcohol use disorders.


Asunto(s)
Alcoholismo , Consumo Excesivo de Bebidas Alcohólicas , Depresores del Sistema Nervioso Central/farmacología , Etanol/farmacología , Hipocampo , Microglía , Alcoholismo/inmunología , Alcoholismo/metabolismo , Amígdala del Cerebelo/efectos de los fármacos , Amígdala del Cerebelo/inmunología , Amígdala del Cerebelo/metabolismo , Animales , Conducta Animal/fisiología , Consumo Excesivo de Bebidas Alcohólicas/inmunología , Consumo Excesivo de Bebidas Alcohólicas/metabolismo , Depresores del Sistema Nervioso Central/administración & dosificación , Modelos Animales de Enfermedad , Etanol/administración & dosificación , Hipocampo/efectos de los fármacos , Hipocampo/inmunología , Hipocampo/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Microglía/efectos de los fármacos , Microglía/inmunología , Microglía/metabolismo
20.
J Emerg Med ; 61(4): 396-405, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34176685

RESUMEN

BACKGROUND: Transgender and gender nonbinary (trans/NB) individuals face many barriers to accessing health care in the United States due to systemic and clinician discrimination. Such experiences can lead to avoidance or delays in seeking care. These issues are relevant for emergency department (ED) clinicians and staff because trans/NB patients may use the ED in times of crisis. OBJECTIVES: The purpose of this study was to qualitatively explore experiences of trans/NB individuals accessing health care in the ED and provide recommendations for improvements. METHODS: This study involved semi-structured qualitative interviews with nine trans/NB individuals living in Arkansas about their experiences when visiting local EDs. RESULTS: Interviews revealed four main themes: 1) system and structural issues; 2) interactions with clinicians/staff influence care received; 3) perceptions of clinician knowledge and education about trans/NB health; and 4) impact on future health and health care access. Participants recommended education for current and future ED clinicians and staff to improve knowledge of best practices for trans/NB health care. Recommendations were also made to improve ED policy for inclusive and affirming intake processes, intake forms, and electronic health record (EHR) documentation, including documentation and use of patients' chosen name and pronouns. CONCLUSION: The negative experiences and discrimination reported by trans/NB patients in ED visits underscores the importance of improving ED clinician knowledge of gender-affirming care practices, ED intake policies and practices, and EHR documentation in EDs.


Asunto(s)
Personas Transgénero , Escolaridad , Servicio de Urgencia en Hospital , Accesibilidad a los Servicios de Salud , Humanos , Políticas , Estados Unidos
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