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1.
Am J Physiol Endocrinol Metab ; 326(1): E61-E72, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37991451

RESUMEN

Acute ingestion of the exogenous ketone monoester supplement [(R)-3-hydroxybutyl-(R)-3-hydroxybutyrate] lowers blood glucose, suggesting therapeutic potential in individuals with impaired glucose metabolism. However, it is unknown how acute or repeated ingestion of exogenous ketones affects blood glucose control in individuals with type 2 diabetes (T2D). We conducted two randomized, counterbalanced, double-blind, placebo-controlled crossover trials to determine if 1) acute exogenous ketone monoester (0.3 g/kg body mass; N = 18) or 2) 14-day thrice daily premeal exogenous ketone monoester (15 g; N = 15) supplementation could lower blood glucose in individuals living with T2D. A single dose of the ketone monoester supplement elevated blood ß-OHB to ∼2 mM. There were no differences in the primary outcomes of plasma glucose concentration (acutely) or serum fructosamine (glycemic control across 14 days) between conditions. Ketone monoester ingestion acutely increased insulin and lowered nonesterified fatty acid concentrations; plasma metabolomics confirmed a reduction in multiple free fatty acids species and select gluconeogenic amino acids. In contrast, no changes were observed in fasting metabolic outcomes following 14 days of supplementation. In the context of these randomized controlled trials, acute or repeated ketone monoester ingestion in adults with T2D did not lower blood glucose when consumed acutely in a fasted state and did not improve glycemic control following thrice daily premeal ingestion across 14 days. Future studies exploring the mechanistic basis for the (lack of) glucose-lowering effect of exogenous ketone supplementation in T2D and other populations are warranted.NEW & NOTEWORTHY Exogenous ketone supplements can acutely lower blood glucose, suggesting therapeutic potential in individuals with impaired glucose metabolism. However, the effect of exogenous ketones on glucose metabolism in adults with type 2 diabetes has not been investigated in a controlled setting. In adults with type 2 diabetes, ketone monoester ingestion did not lower blood glucose acutely in a fasted state and did not improve glycemic control across thrice daily premeal ingestion across 14 days.


Asunto(s)
Diabetes Mellitus Tipo 2 , Cetonas , Humanos , Adulto , Cetonas/farmacología , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Control Glucémico , Ácido 3-Hidroxibutírico , Ensayos Clínicos Controlados Aleatorios como Asunto , Suplementos Dietéticos
2.
Crit Care Med ; 52(7): e351-e364, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38535489

RESUMEN

OBJECTIVES: Transitions to new care environments may have unexpected consequences that threaten patient safety. We undertook a quality improvement project using in situ simulation to learn the new patient care environment and expose latent safety threats before transitioning patients to a newly built adult ICU. DESIGN: Descriptive review of a patient safety initiative. SETTING: A newly built 24-bed neurocritical care unit at a tertiary care academic medical center. SUBJECTS: Care providers working in neurocritical care unit. INTERVENTIONS: We implemented a pragmatic three-stage in situ simulation program to learn a new patient care environment, transitioning patients from an open bay unit to a newly built private room-based ICU. The project tested the safety and efficiency of new workflows created by new patient- and family-centric features of the unit. We used standardized patients and high-fidelity mannequins to simulate patient scenarios, with "test" patients created through all electronic databases. Relevant personnel from clinical and nonclinical services participated in simulations and/or observed scenarios. We held a debriefing after each stage and scenario to identify safety threats and other concerns. Additional feedback was obtained via a written survey sent to all participants. We prospectively surveyed for missed latent safety threats for 2 years following the simulation and fixed issues as they arose. MEASUREMENTS AND MAIN RESULTS: We identified and addressed 70 latent safety threats, including issues concerning physical environment, infection prevention, patient workflow, and informatics before the move into the new unit. We also developed an orientation manual that highlighted new physical and functional features of the ICU and best practices gleaned from the simulations. All participants agreed or strongly agreed that simulations were beneficial. Two-year follow-up revealed only two missed latent safety threats. CONCLUSIONS: In situ simulation effectively identifies latent safety threats surrounding the transition to new ICUs and should be considered before moving into new units.


Asunto(s)
Unidades de Cuidados Intensivos , Seguridad del Paciente , Humanos , Unidades de Cuidados Intensivos/organización & administración , Mejoramiento de la Calidad/organización & administración , Entrenamiento Simulado/métodos , Centros Médicos Académicos/organización & administración , Arquitectura y Construcción de Hospitales
3.
Brain ; 146(3): 991-1005, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35348636

RESUMEN

The mechanisms underlying how urban air pollution affects Alzheimer's disease (AD) are largely unknown. Ozone (O3) is a reactive gas component of air pollution linked to increased AD risk, but is confined to the respiratory tract after inhalation, implicating the peripheral immune response to air pollution in AD neuropathology. Here, we demonstrate that O3 exposure impaired the ability of microglia, the brain's parenchymal immune cells, to associate with and form a protective barrier around Aß plaques, leading to augmented dystrophic neurites and increased Aß plaque load. Spatial proteomic profiling analysis of peri-plaque proteins revealed a microenvironment-specific signature of dysregulated disease-associated microglia protein expression and increased pathogenic molecule levels with O3 exposure. Unexpectedly, 5xFAD mice exhibited an augmented pulmonary cell and humoral immune response to O3, supporting that ongoing neuropathology may regulate the peripheral O3 response. Circulating HMGB1 was one factor upregulated in only 5xFAD mice, and peripheral HMGB1 was separately shown to regulate brain Trem2 mRNA expression. These findings demonstrate a bidirectional lung-brain axis regulating the central and peripheral AD immune response and highlight this interaction as a potential novel therapeutic target in AD.


Asunto(s)
Enfermedad de Alzheimer , Proteína HMGB1 , Ozono , Ratones , Animales , Ozono/toxicidad , Ozono/metabolismo , Proteómica , Péptidos beta-Amiloides/metabolismo , Enfermedad de Alzheimer/patología , Encéfalo/patología , Pulmón/metabolismo , Pulmón/patología , Placa Amiloide/patología , Microglía/metabolismo , Ratones Transgénicos , Modelos Animales de Enfermedad , Glicoproteínas de Membrana/metabolismo , Receptores Inmunológicos
4.
Artículo en Inglés | MEDLINE | ID: mdl-38786980

RESUMEN

OBJECTIVES: Inhaled nitric oxide (iNO) is a selective pulmonary vasodilator. It is expensive, frequently used, and not without risk. There is limited evidence supporting a standard approach to initiation and weaning. Our objective was to optimize the use of iNO in the cardiac ICU (CICU), PICU, and neonatal ICU (NICU) by establishing a standard approach to iNO utilization. DESIGN: A quality improvement study using a prospective cohort design with historical controls. SETTING: Four hundred seven-bed free standing quaternary care academic children's hospital. PATIENTS: All patients on iNO in the CICU, PICU, and NICU from January 1, 2017 to December 31, 2022. INTERVENTIONS: Unit-specific standard approaches to iNO initiation and weaning. MEASUREMENTS AND MAIN RESULTS: Sixteen thousand eighty-seven patients were admitted to the CICU, PICU, and NICU with 9343 in the pre-iNO pathway era (January 1, 2017 to June 30, 2020) and 6744 in the postpathway era (July 1, 2020 to December 31, 2022). We found a decrease in the percentage of CICU patients initiated on iNO from 17.8% to 11.8% after implementation of the iNO utilization pathway. We did not observe a change in iNO utilization between the pre- and post-iNO pathway eras in either the PICU or NICU. Based on these data, we estimate 564 total days of iNO (-24%) were saved over 24 months in association with the standard pathway in the CICU, with associated cost savings. CONCLUSIONS: Implementation of a standard pathway for iNO use was associated with a statistically discernible reduction in total iNO usage in the CICU, but no change in iNO use in the NICU and PICU. These differential results likely occurred because of multiple contextual factors in each care setting.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38908464

RESUMEN

BACKGROUND: Accurate insertion of the glenoid guide pin in shoulder arthroplasty (RSA) is important for obtaining optimized glenoid component position and orientation. The objective of this study was to evaluate and compare the accuracy of three glenoid guide pin insertion techniques: 1) traditional software planning using freehand guide pin insertion (freehand), 2) guide pin insertion utilizing patient-specific instrumentation (PSI), and 3) using a mixed reality navigation (MR-NAV) system. METHODS: Twenty (20) computer tomography (CT) scans were obtained from patients exhibiting glenoid erosion patterns according to the Walch and Favard classifications. Cases were planned using validated three-dimensional (3D) preoperative planning software. The CT data was then used to 3D print triplicate plastic models of each glenoid to evaluate the three guide pin insertion techniques. The first technique employed traditional software planning with freehand guide pin insertion. The second method used preoperatively planned PSI guides, while the third utilized a MR-NAV system, which provided real-time holographic guidance during guide pin insertion. Once all guide pins had been inserted into the models, an independent optical tracking system and custom digitization device was used to quantify the position and orientation of each guide pin relative to the glenoid. The outcomes for this study included the absolute mean error in guide pin inclination, version, and entry point relative to the preoperative plan. The absolute Total Global Error was also assessed, which was defined as the sum of the absolute guide pin orientation and position error relative to the preoperative plan. RESULTS: No statistically significant differences between MR-NAV and PSI were found for the inclination error (2±1° versus 2±1°; P=0.056), version error (1±1° versus 1±1°; P=1.000), and Total Global Error (5±1 [mm+deg] versus 5±1 [mm+deg], P=1.000), respectively. The freehand technique produced significantly greater error than MR-NAV and PSI for inclination (5±3°, P≤0.017), version (4±3°, P≤0.032) and Total Global Error (8±3 [mm+deg], P<0.001). No statistically significant differences in the entry point error were observed between all guide pin insertion methods (P≥0.058). DISCUSSION: These results demonstrate that the precision and accuracy of MR-NAV is comparable to PSI and superior to a freehand technique for glenoid guide pin insertion in-vitro. Further study is needed to compare the accuracy of these techniques intra-operatively, in addition to assessing a potential learning curve between surgeons of varying experience with the MR-NAV system.

6.
Artículo en Inglés | MEDLINE | ID: mdl-38750787

RESUMEN

BACKGROUND: In 1993, Kouvalchouk described an acromial bone block with a pedicled deltoid flap for the treatment of posterior shoulder instability. This procedure provides a "double blocking" effect in that the acromial autograft restores posterior glenoid bone loss and the deltoid flap functions as a muscular "hammock" resembling the sling effect of the conjoint in the Latarjet procedure. The primary aim of this study was to compare the Kouvalchouk procedure to distal tibial allograft (DTA) reconstruction for the management of posterior shoulder instability with associated bone loss, while the secondary aim was to evaluate the deltoid hammock effect. s METHODS: Ten upper extremity cadavers were evaluated using a validated shoulder testing apparatus in 0° and 60° of glenohumeral abduction in the scapular plane. Testing was first performed on the normal shoulder state and was followed by the creation of a 20% posterior glenoid defect. Subsequently, the Kouvalchouk and DTA procedures were conducted. Forces of 0N, 5N, 10N and 15N were applied to the posterior deltoid tendinous insertion on the Kouvalchouk graft along the physiological muscle line-of-action to evaluate the 'hammock" effect of this procedure. Testing was additionally performed on the Kouvalchouk bone graft with the deltoid muscle sectioned from its bony attachment. For all test states, a posteriorly directed force was applied to the humeral head perpendicular to the direction of the glenoid bone defect, with the associated translation quantified using an optical tracking system. The outcome variable was posterior translation of the humeral head at an applied force magnitude of 30N. RESULTS: The Kouvalchouk procedure with the loaded deltoid flap (10N: P=0.039 and 15N: P<0.001) was significantly better at reducing posterior humeral head translation than the DTA. Overall, increased glenohumeral stability was observed with increased force applied to the posterior deltoid flap in the Kouvalchouk procedure. The 15N Kouvalchouk was most effective at preventing posterior humeral translation, and the difference was statistically significant compared with the 20% glenoid defect (P=0.003), detached Kouvalchouk (P<0.001), and 0N Kouvalchouk (P<0.001). The 15N Kouvalchouk procedure restored posterior shoulder joint stability to near normal levels, such that it was not significantly different from the intact state (P=0.203). CONCLUSIONS: The Kouvalchouk procedure with load applied to the deltoid was found to be biomechanically superior to the DTA for the management of posterior shoulder instability with associated bone loss. Additionally, the results confirmed the presence and effectiveness of the deltoid "hammock" effect.

7.
J Shoulder Elbow Surg ; 33(1): 164-171, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37507001

RESUMEN

BACKGROUND: Stemless anatomic humeral components are commonly used and are an accepted alternative to traditional stemmed implants in patients with good bone quality. Presently, little literature exists on the design and implantation parameters that influence primary time-zero fixation of stemless reverse humeral implants. Accordingly, this finite element analysis study assessed the surgical implantation variable of neck-shaft angle, and its effect on the primary time-zero fixation of reversed stemless humeral implants. METHODS: Eight computed tomography-derived humeral finite element models were used to examine a generic stemless humeral implant at varying neck-shaft angles of 130°, 135°, 140°, 145°, and 150°. Four loading scenarios (30° shoulder abduction with neutral forearm rotation, 30° shoulder abduction with forearm supination, a head-height lifting motion, and a single-handed steering motion) were employed. Implantation inclinations were compared based on the maximum bone-implant interface distraction detected after loading. RESULTS: The implant-bone distraction was greatest in the 130° neck-shaft angle implantation cases. All implant loading scenarios elicited significantly lower micromotion magnitudes when neck-shaft angle was increased (P = .0001). With every 5° increase in neck-shaft angle, there was an average 17% reduction in bone-implant distraction. CONCLUSIONS: The neck-shaft angle of implantation for a stemless reverse humeral component is a modifiable parameter that appears to influence time-zero implant stability. Lower, more varus, neck-shaft angles increase bone-implant distractions with simulated activities of daily living. It is therefore suggested that humeral head osteotomies at a higher neck-shaft angle may be beneficial to maximize stemless humeral component stability.


Asunto(s)
Artroplastía de Reemplazo de Hombro , Artroplastia de Reemplazo , Articulación del Hombro , Humanos , Articulación del Hombro/diagnóstico por imagen , Articulación del Hombro/cirugía , Actividades Cotidianas , Cabeza Humeral/cirugía , Diseño de Prótesis
8.
Alzheimers Dement ; 20(5): 3551-3566, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38624088

RESUMEN

INTRODUCTION: Ozone (O3) is an air pollutant associated with Alzheimer's disease (AD) risk. The lung-brain axis is implicated in O3-associated glial and amyloid pathobiology; however, the role of disease-associated astrocytes (DAAs) in this process remains unknown. METHODS: The O3-induced astrocyte phenotype was characterized in 5xFAD mice by spatial transcriptomics and proteomics. Hmgb1fl/fl LysM-Cre+ mice were used to assess the role of peripheral myeloid cell high mobility group box 1 (HMGB1). RESULTS: O3 increased astrocyte and plaque numbers, impeded the astrocyte proteomic response to plaque deposition, augmented the DAA transcriptional fingerprint, increased astrocyte-microglia contact, and reduced bronchoalveolar lavage immune cell HMGB1 expression in 5xFAD mice. O3-exposed Hmgb1fl/fl LysM-Cre+ mice exhibited dysregulated DAA mRNA markers. DISCUSSION: Astrocytes and peripheral myeloid cells are critical lung-brain axis interactors. HMGB1 loss in peripheral myeloid cells regulates the O3-induced DAA phenotype. These findings demonstrate a mechanism and potential intervention target for air pollution-induced AD pathobiology. HIGHLIGHTS: Astrocytes are part of the lung-brain axis, regulating how air pollution affects plaque pathology. Ozone (O3) astrocyte effects are associated with increased plaques and modified by plaque localization. O3 uniquely disrupts the astrocyte transcriptomic and proteomic disease-associated astrocyte (DAA) phenotype in plaque associated astrocytes (PAA). O3 changes the PAA cell contact with microglia and cell-cell communication gene expression. Peripheral myeloid cell high mobility group box 1 regulates O3-induced transcriptomic changes in the DAA phenotype.


Asunto(s)
Enfermedad de Alzheimer , Astrocitos , Proteína HMGB1 , Ozono , Animales , Astrocitos/metabolismo , Astrocitos/patología , Proteína HMGB1/metabolismo , Ratones , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Ratones Transgénicos , Modelos Animales de Enfermedad , Encéfalo/patología , Encéfalo/metabolismo , Placa Amiloide/patología , Placa Amiloide/metabolismo , Microglía/metabolismo , Contaminantes Atmosféricos , Pulmón/patología , Péptidos beta-Amiloides/metabolismo
9.
J Zoo Wildl Med ; 54(4): 704-712, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38251993

RESUMEN

Cownose rays (Rhinoptera bonasus) are common elasmobranchs in zoos and aquaria; however, there is a lack of published information regarding ocular findings in this species. Intraocular pressure (IOP) was measured in a total of 52 cownose rays (Rhinoptera bonasus) from two unrelated aquaria (n = 22 from A1, n = 30 from A2) using a TonoVet rebound tonometer on two settings (dog = D, and unidentified species = P) as part of a full ophthalmologic examination. Adult (n = 38) and juvenile (n = 14) rays were sampled out of water briefly in sternal recumbency. Intraocular pressure (mean ± SD [range]) in the D setting (9.10 ± 2.57 [4-18] mmHg) was higher than the P setting (5.21 ± 2.32 [0-12] mmHg) (P<0.001). Statistical analysis revealed no difference in IOP between right and left eyes, and no correlation between body weight and IOP. No differences in IOP between sex, age group, and location were identified in either setting. However, a significant difference was observed between levels of severity of corneal disease in IOP D setting (P=0.006) and P setting (P=0.024), and levels of severity of intraocular disease in IOP D setting (P=0.034) only. This study provides baseline IOP values using rebound tonometry in aquarium-housed cownose rays with apparent corneal and intraocular lesions and reveals that the D setting may be more sensitive in identifying IOP changes in eyes with intraocular disease.


Asunto(s)
Presión Intraocular , Rajidae , Animales , Perros , Tonometría Ocular/veterinaria , Peso Corporal , Córnea
10.
J Zoo Wildl Med ; 54(4): 692-703, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38251992

RESUMEN

Cownose rays (Rhinoptera bonasus) are susceptible to ocular disease with their prominent globes, but despite being popular animals housed in aquaria, there is little published information about their normal ocular anatomy and common pathologic ocular findings. A total of 63 live cownose rays (CNR) from three unrelated, separately housed groups had ocular examinations, and 5 adult rays were selected for ocular ultrasound. All examinations were performed out of the water, and most without anesthesia. Clinical findings were described, categorized, and scored by severity. Sixty-two of 63 rays (123 eyes) had clinical abnormalities, including 110 eyes with corneal pathology (mild = 76, moderate/severe = 34) and 74 eyes with intraocular pathology (mild = 44, moderate/severe = 30). Grey-to-white corneal opacities were the most common pathology (n = 58 rays/100 eyes) followed by cataracts (n = 41 rays/58 eyes), then persistent (or dysplastic) pupillary membranes (n = 14 rays/15 eyes). Most pathologic findings appeared inactive, but one aquarium had several CNR with active ocular pathology. There was a significant association between the diagnosis of moderate/severe corneal and intraocular pathology with age (P = 0.008 and P = 0.014, respectively) and weight (P = 0.001 and P = 0.039, respectively), as well as moderate/severe corneal pathology and group sampled (P = 0.03). There were no other significant variables identified. Additionally, histopathology of 14 eyes (11 rays) from two different facilities were examined, with keratitis (n = 8) and uveitis (n = 2) as the most common lesions. This study shows a high prevalence of pathologic ocular findings in cownose ray eyes with heavier adults more likely to be affected than lighter juveniles. Comprehensive ocular evaluation is important in this species and serial ocular exams and future studies should be pursued to monitor ocular disease progression and better understand possible etiologies.


Asunto(s)
Anestesia , Catarata , Animales , Córnea , Catarata/veterinaria , Anestesia/veterinaria
11.
J Proteome Res ; 22(8): 2608-2619, 2023 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-37450889

RESUMEN

During the COVID-19 pandemic, impaired immunity and medical interventions resulted in cases of secondary infections. The clinical difficulties and dangers associated with secondary infections in patients necessitate the exploration of their microbiome. Metaproteomics is a powerful approach to study the taxonomic composition and functional status of the microbiome under study. In this study, the mass spectrometry (MS)-based data of nasopharyngeal swab samples from COVID-19 patients was used to investigate the metaproteome. We have established a robust bioinformatics workflow within the Galaxy platform, which includes (a) generation of a tailored database of the common respiratory tract pathogens, (b) database search using multiple search algorithms, and (c) verification of the detected microbial peptides. The microbial peptides detected in this study, belong to several opportunistic pathogens such as Streptococcus pneumoniae, Klebsiella pneumoniae, Rhizopus microsporus, and Syncephalastrum racemosum. Microbial proteins with a role in stress response, gene expression, and DNA repair were found to be upregulated in severe patients compared to negative patients. Using parallel reaction monitoring (PRM), we confirmed some of the microbial peptides in fresh clinical samples. MS-based clinical metaproteomics can serve as a powerful tool for detection and characterization of potential pathogens, which can significantly impact the diagnosis and treatment of patients.


Asunto(s)
COVID-19 , Coinfección , Humanos , COVID-19/diagnóstico , Pandemias , Péptidos , Nasofaringe
12.
J Proteome Res ; 22(2): 594-604, 2023 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-36688735

RESUMEN

Protein quantitation via mass spectrometry relies on peptide proxies for the parent protein from which abundances are estimated. Owing to the variability in signal from individual peptides, accurate absolute quantitation usually relies on the addition of an external standard. Typically, this involves stable isotope-labeled peptides, delivered singly or as a concatenated recombinant protein. Consequently, the selection of the most appropriate surrogate peptides and the attendant design in recombinant proteins termed QconCATs are challenges for proteome science. QconCATs can now be built in a "a-la-carte" assembly method using synthetic biology: ALACATs. To assist their design, we present "AlacatDesigner", a tool that supports the peptide selection for recombinant protein standards based on the user's target protein. The user-customizable tool considers existing databases, occurrence in the literature, potential post-translational modifications, predicted miscleavage, predicted divergence of the peptide and protein quantifications, and ionization potential within the mass spectrometer. We show that peptide selections are enriched for good proteotypic and quantotypic candidates compared to empirical data. The software is freely available to use either via a web interface AlacatDesigner, downloaded as a Desktop application or imported as a Python package for the command line interface or in scripts.


Asunto(s)
Péptidos , Programas Informáticos , Péptidos/química , Espectrometría de Masas , Proteoma/metabolismo , Proteínas Recombinantes
13.
Physiol Genomics ; 55(3): 132-146, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36717164

RESUMEN

Genetic factors affect an individual's risk of developing obesity, but in most cases each genetic variant has a small effect. Discovery of genes that regulate obesity may provide clues about its underlying biological processes and point to new ways the disease can be treated. Preclinical animal models facilitate genetic discovery in obesity because environmental factors can be better controlled compared with the human population. We studied inbred mouse strains to identify novel genes affecting obesity and glucose metabolism. BTBR T+ Itpr3tf/J (BTBR) mice are fatter and more glucose intolerant than C57BL/6J (B6) mice. Prior genetic studies of these strains identified an obesity locus on chromosome 2. Using congenic mice, we found that obesity was affected by a ∼316 kb region, with only two known genes, pyruvate dehydrogenase kinase 1 (Pdk1) and integrin α 6 (Itga6). Both genes had mutations affecting their amino acid sequence and reducing mRNA levels. Both genes have known functions that could modulate obesity, lipid metabolism, insulin secretion, and/or glucose homeostasis. We hypothesized that genetic variation in or near Pdk1 or Itga6 causing reduced Pdk1 and Itga6 expression would promote obesity and impaired glucose tolerance. We used knockout mice lacking Pdk1 or Itga6 fed an obesigenic diet to test this hypothesis. Under the conditions we studied, we were unable to detect an individual contribution of either Pdk1 or Itga6 to body weight. During our studies, with conditions outside our control, we were unable to reproduce some of our previous body weight data. However, we identified a previously unknown role for Pdk1 in cardiac cholesterol metabolism providing the basis for future investigations. The studies described in this paper highlight the importance and the challenge using physiological outcomes to study obesity genes in mice.


Asunto(s)
Glucosa , Obesidad , Ratones , Humanos , Animales , Ratones Endogámicos C57BL , Obesidad/genética , Obesidad/metabolismo , Peso Corporal/genética , Glucosa/metabolismo , Ratones Endogámicos , Peso al Nacer
14.
Am J Physiol Endocrinol Metab ; 324(1): E42-E55, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36449570

RESUMEN

The release of peptide hormones is predominantly regulated by a transient increase in cytosolic Ca2+ concentration ([Ca2+]c). To trigger exocytosis, Ca2+ ions enter the cytosol from intracellular Ca2+ stores or from the extracellular space. The molecular events of late stages of exocytosis, and their dependence on [Ca2+]c, were extensively described in isolated single cells from various endocrine glands. Notably, less work has been done on endocrine cells in situ to address the heterogeneity of [Ca2+]c events contributing to a collective functional response of a gland. For this, ß cell collectives in a pancreatic islet are particularly well suited as they are the smallest, experimentally manageable functional unit, where [Ca2+]c dynamics can be simultaneously assessed on both cellular and collective level. Here, we measured [Ca2+]c transients across all relevant timescales, from a subsecond to a minute time range, using high-resolution imaging with a low-affinity Ca2+ sensor. We quantified the recordings with a novel computational framework for automatic image segmentation and [Ca2+]c event identification. Our results demonstrate that under physiological conditions the duration of [Ca2+]c events is variable, and segregated into three reproducible modes, subsecond, second, and tens of seconds time range, and are a result of a progressive temporal summation of the shortest events. Using pharmacological tools we show that activation of intracellular Ca2+ receptors is both sufficient and necessary for glucose-dependent [Ca2+]c oscillations in ß cell collectives, and that a subset of [Ca2+]c events could be triggered even in the absence of Ca2+ influx across the plasma membrane. In aggregate, our experimental and analytical platform was able to readily address the involvement of intracellular Ca2+ receptors in shaping the heterogeneity of [Ca2+]c responses in collectives of endocrine cells in situ.NEW & NOTEWORTHY Physiological glucose or ryanodine stimulation of ß cell collectives generates a large number of [Ca2+]c events, which can be rapidly assessed with our newly developed automatic image segmentation and [Ca2+]c event identification pipeline. The event durations segregate into three reproducible modes produced by a progressive temporal summation. Using pharmacological tools, we show that activation of ryanodine intracellular Ca2+ receptors is both sufficient and necessary for glucose-dependent [Ca2+]c oscillations in ß cell collectives.


Asunto(s)
Células Secretoras de Insulina , Islotes Pancreáticos , Citosol/metabolismo , Rianodina/metabolismo , Rianodina/farmacología , Células Secretoras de Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Glucosa/metabolismo , Calcio/metabolismo , Señalización del Calcio
15.
Breast Cancer Res ; 25(1): 99, 2023 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-37608351

RESUMEN

BACKGROUND: Obesity increases breast cancer risk and breast cancer-specific mortality, particularly for people with estrogen receptor (ER)-positive tumors. Body mass index (BMI) is used to define obesity, but it may not be the best predictor of breast cancer risk or prognosis on an individual level. Adult weight gain is an independent indicator of breast cancer risk. Our previous work described a murine model of obesity, ER-positive breast cancer, and weight gain and identified fibroblast growth factor receptor (FGFR) as a potential driver of tumor progression. During adipose tissue expansion, the FGF1 ligand is produced by hypertrophic adipocytes as a stimulus to stromal preadipocytes that proliferate and differentiate to provide additional lipid storage capacity. In breast adipose tissue, FGF1 production may stimulate cancer cell proliferation and tumor progression. METHODS: We explored the effects of FGF1 on ER-positive endocrine-sensitive and resistant breast cancer and compared that to the effects of the canonical ER ligand, estradiol. We used untargeted proteomics, specific immunoblot assays, gene expression profiling, and functional metabolic assessments of breast cancer cells. The results were validated in tumors from obese mice and breast cancer datasets from women with obesity. RESULTS: FGF1 stimulated ER phosphorylation independently of estradiol in cells that grow in obese female mice after estrogen deprivation treatment. Phospho- and total proteomic, genomic, and functional analyses of endocrine-sensitive and resistant breast cancer cells show that FGF1 promoted a cellular phenotype characterized by glycolytic metabolism. In endocrine-sensitive but not endocrine-resistant breast cancer cells, mitochondrial metabolism was also regulated by FGF1. Comparison of gene expression profiles indicated that tumors from women with obesity shared hallmarks with endocrine-resistant breast cancer cells. CONCLUSIONS: Collectively, our data suggest that one mechanism by which obesity and weight gain promote breast cancer progression is through estrogen-independent ER activation and cancer cell metabolic reprogramming, partly driven by FGF/FGFR. The first-line treatment for many patients with ER-positive breast cancer is inhibition of estrogen synthesis using aromatase inhibitors. In women with obesity who are experiencing weight gain, locally produced FGF1 may activate ER to promote cancer cell metabolic reprogramming and tumor progression independently of estrogen.


Asunto(s)
Neoplasias de la Mama , Factor 1 de Crecimiento de Fibroblastos , Receptores de Estrógenos , Animales , Femenino , Ratones , Estradiol , Estrógenos , Factor 1 de Crecimiento de Fibroblastos/metabolismo , Ligandos , Obesidad/complicaciones , Proteómica , Receptores de Estrógenos/genética , Aumento de Peso , Neoplasias de la Mama/metabolismo
16.
Expert Rev Proteomics ; 20(11): 251-266, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37787106

RESUMEN

INTRODUCTION: Continuous advances in mass spectrometry (MS) technologies have enabled deeper and more reproducible proteome characterization and a better understanding of biological systems when integrated with other 'omics data. Bioinformatic resources meeting the analysis requirements of increasingly complex MS-based proteomic data and associated multi-omic data are critically needed. These requirements included availability of software that would span diverse types of analyses, scalability for large-scale, compute-intensive applications, and mechanisms to ease adoption of the software. AREAS COVERED: The Galaxy ecosystem meets these requirements by offering a multitude of open-source tools for MS-based proteomics analyses and applications, all in an adaptable, scalable, and accessible computing environment. A thriving global community maintains these software and associated training resources to empower researcher-driven analyses. EXPERT OPINION: The community-supported Galaxy ecosystem remains a crucial contributor to basic biological and clinical studies using MS-based proteomics. In addition to the current status of Galaxy-based resources, we describe ongoing developments for meeting emerging challenges in MS-based proteomic informatics. We hope this review will catalyze increased use of Galaxy by researchers employing MS-based proteomics and inspire software developers to join the community and implement new tools, workflows, and associated training content that will add further value to this already rich ecosystem.


Asunto(s)
Proteómica , Humanos , Biología Computacional/métodos , Espectrometría de Masas/métodos , Proteómica/métodos , Programas Informáticos
17.
Ann Surg Oncol ; 30(11): 6777-6785, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37349613

RESUMEN

BACKGROUND: Incorporation of patient-reported outcomes such as health-related quality of life has become increasingly important in the management of chronic diseases such as cancer. In this prospective study, we examined the effect of surgical resection on quality of life in patients with intestinal and pancreatic neuroendocrine tumors (NETs). METHODS: Thirty-two patients underwent NET resection at our institution from January 2020 to January 2022. All patients completed the 12-item short-form quality-of-life survey prior to surgery, as well as at the 3-, 6-, and 12-month postoperative time points. The presence and severity of specific carcinoid syndrome symptoms (diarrhea, flushing, and abdominal pain) were also recorded during pre- and postoperative appointments. RESULTS: Patients experienced significant increases in both mental and physical health after surgery. Mental health scores significantly increased at all three time points (baseline: 51.33; 3-month: 53.17, p = 0.02; 6-month: 57.20, p < 0.001; 12-month: 57.34, p = 0.002), and physical health scores increased at 6 and 12 months (baseline: 50.39; 6-month: 53.16, p = 0.04; 12-month: 55.02, p = 0.003). Younger patients benefited more in terms of physical health, while older patients had more significant increases in mental health. Patients with metastatic disease, larger primary tumors, and those receiving medical therapy had lower baseline quality-of-life scores and greater improvements after surgery. The vast majority of patients in this study also experienced alleviation of carcinoid syndrome symptoms. CONCLUSIONS: In addition to prolonging survival, resection of intestinal and pancreatic NETs leads to significantly improved patient-reported quality of life.


Asunto(s)
Síndrome Carcinoide Maligno , Tumores Neuroendocrinos , Humanos , Estudios Prospectivos , Tumores Neuroendocrinos/patología , Calidad de Vida , Medición de Resultados Informados por el Paciente
18.
FASEB J ; 36(1): e22088, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34921686

RESUMEN

Hyperinsulinemia is commonly viewed as a compensatory response to insulin resistance, yet studies have demonstrated that chronically elevated insulin may also drive insulin resistance. The molecular mechanisms underpinning this potentially cyclic process remain poorly defined, especially on a transcriptome-wide level. Transcriptomic meta-analysis in >450 human samples demonstrated that fasting insulin reliably and negatively correlated with INSR mRNA in skeletal muscle. To establish causality and study the direct effects of prolonged exposure to excess insulin in muscle cells, we incubated C2C12 myotubes with elevated insulin for 16 h, followed by 6 h of serum starvation, and established that acute AKT and ERK signaling were attenuated in this model of in vitro hyperinsulinemia. Global RNA-sequencing of cells both before and after nutrient withdrawal highlighted genes in the insulin receptor (INSR) signaling, FOXO signaling, and glucose metabolism pathways indicative of 'hyperinsulinemia' and 'starvation' programs. Consistently, we observed that hyperinsulinemia led to a substantial reduction in Insr gene expression, and subsequently a reduced surface INSR and total INSR protein, both in vitro and in vivo. Bioinformatic modeling combined with RNAi identified SIN3A as a negative regulator of Insr mRNA (and JUND, MAX, and MXI as positive regulators of Irs2 mRNA). Together, our analysis identifies mechanisms which may explain the cyclic processes underlying hyperinsulinemia-induced insulin resistance in muscle, a process directly relevant to the etiology and disease progression of type 2 diabetes.


Asunto(s)
Antígenos CD/biosíntesis , Regulación hacia Abajo , Hiperinsulinismo/metabolismo , Resistencia a la Insulina , Músculo Esquelético/metabolismo , ARN Mensajero/biosíntesis , Receptor de Insulina/biosíntesis , Animales , Antígenos CD/genética , Línea Celular , Humanos , Hiperinsulinismo/genética , Ratones , Ratones Noqueados , ARN Mensajero/genética , RNA-Seq , Receptor de Insulina/genética
19.
Amino Acids ; 55(12): 1857-1866, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37966501

RESUMEN

Qualitative and quantitatively appropriate insulin secretion is essential for optimal control of blood glucose. Beta-cells of the pancreas produce and secrete insulin in response to glucose and non-glucose stimuli including amino acids. In this manuscript, we review the literature on amino acid-stimulated insulin secretion in oral and intravenous in vivo studies, in addition to the in vitro literature, and describe areas of consensus and gaps in understanding. We find promising evidence that the synergism of amino acid-stimulated insulin secretion could be exploited to develop novel therapeutics, but that a systematic approach to investigating these lines of evidence is lacking. We highlight evidence that supports the relative preservation of amino acid-stimulated insulin secretion compared to glucose-stimulated insulin secretion in type 2 diabetes, and make the case for the therapeutic potential of amino acids. Finally, we make recommendations for research and describe the potential clinical utility of nutrient-based treatments for type 2 diabetes including remission services.


Asunto(s)
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Secreción de Insulina , Aminoácidos/metabolismo , Insulina/metabolismo , Glucosa/metabolismo
20.
J Cardiothorac Vasc Anesth ; 37(2): 308-313, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36372718

RESUMEN

The clinical uses of perioperative transesophageal echocardiography have grown exponentially in recent years for both cardiac and noncardiac surgical patients. Yet, echocardiography is a complex skill that also requires an advanced understanding of human cardiac anatomy. Although simulation has changed the way echocardiography is taught, most available systems are still limited by investment costs, accessibility, and qualities of the input cardiac 3-dimensional models. In this report, the authors discuss the development of an online simulator using a high-resolution human heart scan that accurately represents real cardiac anatomies, and that should be accessible to a wide range of learners without space or time limitations.


Asunto(s)
Ecocardiografía Tridimensional , Ecocardiografía Transesofágica , Humanos , Ecocardiografía Transesofágica/métodos , Ecocardiografía , Corazón , Simulación por Computador , Factores de Tiempo
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