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1.
Diabetes Obes Metab ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720199

RESUMO

Interventions aimed at weight control often have limited effectiveness in combating obesity. This review explores how obesity-induced dysfunction in white (WAT) and brown adipose tissue (BAT), skeletal muscle, and the brain blunt weight loss, leading to retention of stored fat. In obesity, increased adrenergic stimulation and inflammation downregulate ß-adrenoreceptors and impair catecholaminergic signalling in adipocytes. This disrupts adrenergic-mediated lipolysis, diminishing lipid oxidation in both white and brown adipocytes, lowering thermogenesis and blunting fat loss. Emerging evidence suggests that WAT fibrosis is associated with worse weight loss outcomes; indeed, limiting collagen and laminin-α4 deposition mitigates WAT accumulation, enhances browning, and protects against high-fat-diet-induced obesity. Obesity compromises mitochondrial oxidative capacity and lipid oxidation in skeletal muscle, impairing its ability to switch between glucose and lipid metabolism in response to varying nutrient levels and exercise. This dysfunctional phenotype in muscle is exacerbated in the presence of obesity-associated sarcopenia. Additionally, obesity suppresses sarcolipin-induced sarcoplasmic reticulum calcium ATPase (SERCA) activation, resulting in reduced oxidative capacity, diminished energy expenditure, and increased adiposity. In the hypothalamus, obesity and overnutrition impair insulin and leptin signalling. This blunts central satiety signals, favouring a shift in energy balance toward energy conservation and body fat retention. Moreover, both obese animals and humans demonstrate impaired dopaminergic signalling and diminished responses to nutrient intake in the striatum, which tend to persist after weight loss. This may result in enduring inclinations toward overeating and a sedentary lifestyle. Collectively, the tissue adaptations described pose significant challenges to effectively achieving and sustaining weight loss in obesity.

2.
LGBT Health ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557157

RESUMO

Fertility preservation is the process of collecting and storing oocytes, sperm, or reproductive tissue so that a person may retain their ability to have biologically related children. In instances of infertility caused by medical intervention or an underlying medical condition, this procedure is often sought by affected patient populations. U.S. Title 21 regulations have produced disparities in access, disproportionately restricting services for sexually and gender diverse subpopulations capable of producing sperm. This article examines policies contributing to these disparities, explores how these policies may translate to real-world health care delivery, and proposes policy changes that would increase equitable access to care.

3.
Cardiol Young ; : 1-9, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38682563

RESUMO

OBJECTIVE: Challenges to communication between families and care providers of paediatric patients in intensive care units (ICU) include variability of communication preferences, mismatched goals of care, and difficulties carrying forward family preferences from provider to provider. Our objectives were to develop and test an assessment tool that queries parents of children requiring cardiac intensive care about their communication preferences and to determine if this tool facilitates patient-centred care and improves families' ICU experience. DESIGN: In this quality improvement initiative, a novel tool was developed, the Parental Communication Assessment (PCA), which asked parents with children hospitalised in the cardiac ICU about their communication preferences. Participants were prospectively randomised to the intervention group, which received the PCA, or to standard care. All participants completed a follow-up survey evaluating satisfaction with communication. MAIN RESULTS: One hundred thirteen participants enrolled and 56 were randomised to the intervention group. Participants who received the PCA preferred detail-oriented communication over big picture. Most parents understood the daily discussions on rounds (64%) and felt comfortable expressing concerns (68%). Eighty-six percent reported the PCA was worthwhile. Parents were generally satisfied with communication. However, an important proportion felt unprepared for difficult decisions or setbacks, inadequately included or supported in decision-making, and that they lacked control over their child's care. There were no significant differences between the intervention and control groups in their communication satisfaction results. CONCLUSIONS: Parents with children hospitalised in the paediatric ICU demonstrated diverse communication preferences. Most participants felt overall satisfied with communication, but individualising communication with patients' families according to their preferences may improve their experience.

4.
bioRxiv ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38659843

RESUMO

In patients with atrophic age-related macular degeneration, subretinal photovoltaic implant (PRIMA) provided visual acuity up to 20/440, matching its 100µm pixels size. Next-generation implants with smaller pixels should significantly improve the acuity. This study in rats evaluates removal of a subretinal implant, replacement with a newer device, and the resulting grating acuity in-vivo. Six weeks after the initial implantation with planar and 3-dimensional devices, the retina was re-detached, and the devices were successfully removed. Histology demonstrated a preserved inner nuclear layer. Re-implantation of new devices into the same location demonstrated retinal re-attachment to a new implant. New devices with 22µm pixels increased the grating acuity from the 100µm capability of PRIMA implants to 28µm, reaching the limit of natural resolution in rats. Reimplanted devices exhibited the same stimulation threshold as for the first implantation of the same implants in a control group. This study demonstrates the feasibility of safely upgrading the subretinal photovoltaic implants to improve prosthetic visual acuity.

5.
Nature ; 628(8006): 154-161, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38480892

RESUMO

Several genetic risk factors for Alzheimer's disease implicate genes involved in lipid metabolism and many of these lipid genes are highly expressed in glial cells1. However, the relationship between lipid metabolism in glia and Alzheimer's disease pathology remains poorly understood. Through single-nucleus RNA sequencing of brain tissue in Alzheimer's disease, we have identified a microglial state defined by the expression of the lipid droplet-associated enzyme ACSL1 with ACSL1-positive microglia being most abundant in patients with Alzheimer's disease having the APOE4/4 genotype. In human induced pluripotent stem cell-derived microglia, fibrillar Aß induces ACSL1 expression, triglyceride synthesis and lipid droplet accumulation in an APOE-dependent manner. Additionally, conditioned media from lipid droplet-containing microglia lead to Tau phosphorylation and neurotoxicity in an APOE-dependent manner. Our findings suggest a link between genetic risk factors for Alzheimer's disease with microglial lipid droplet accumulation and neurotoxic microglia-derived factors, potentially providing therapeutic strategies for Alzheimer's disease.


Assuntos
Doença de Alzheimer , Apolipoproteína E4 , Gotículas Lipídicas , Microglia , Animais , Feminino , Humanos , Masculino , Camundongos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Apolipoproteína E4/genética , Apolipoproteína E4/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/patologia , Microglia/citologia , Microglia/metabolismo , Microglia/patologia , Triglicerídeos , Proteínas tau , Meios de Cultivo Condicionados , Fosforilação , Predisposição Genética para Doença
6.
J Neural Eng ; 21(1)2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38364290

RESUMO

Objective.Retinal prosthetics offer partial restoration of sight to patients blinded by retinal degenerative diseases through electrical stimulation of the remaining neurons. Decreasing the pixel size enables increasing prosthetic visual acuity, as demonstrated in animal models of retinal degeneration. However, scaling down the size of planar pixels is limited by the reduced penetration depth of the electric field in tissue. We investigated 3-dimensional (3d) structures on top of photovoltaic arrays for enhanced penetration of the electric field, permitting higher resolution implants.Approach.3D COMSOL models of subretinal photovoltaic arrays were developed to accurately quantify the electrodynamics during stimulation and verified through comparison to flat photovoltaic arrays. Models were applied to optimize the design of 3D electrode structures (pillars and honeycombs). Return electrodes on honeycomb walls vertically align the electric field with bipolar cells for optimal stimulation. Pillars elevate the active electrode, thus improving proximity to target neurons. The optimized 3D structures were electroplated onto existing flat subretinal prostheses.Main results.Simulations demonstrate that despite exposed conductive sidewalls, charge mostly flows via high-capacitance sputtered iridium oxide films topping the 3D structures. The 24µm height of honeycomb structures was optimized for integration with the inner nuclear layer cells in the rat retina, whilst 35µm tall pillars were optimized for penetrating the debris layer in human patients. Implantation of released 3D arrays demonstrates mechanical robustness, with histology demonstrating successful integration of 3D structures with the rat retinain-vivo.Significance. Electroplated 3D honeycomb structures produce vertically oriented electric fields, providing low stimulation thresholds, high spatial resolution, and high contrast for pixel sizes down to 20µm. Pillar electrodes offer an alternative for extending past the debris layer. Electroplating of 3D structures is compatible with the fabrication process of flat photovoltaic arrays, enabling much more efficient retinal stimulation.


Assuntos
Membros Artificiais , Degeneração Retiniana , Próteses Visuais , Humanos , Ratos , Animais , Próteses e Implantes , Retina/fisiologia , Neurônios/fisiologia , Estimulação Elétrica , Eletrodos Implantados
7.
bioRxiv ; 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38014082

RESUMO

Objective: High-resolution retinal prosthetics offer partial restoration of sight to patients blinded by retinal degenerative diseases through electrical stimulation of the remaining neurons. Decreasing the pixel size enables an increase in prosthetic visual acuity, as demonstrated in animal models of retinal degeneration. However, scaling down the size of planar pixels is limited by the reduced penetration depth of the electric field in tissue. We investigate 3-dimensional structures on top of the photovoltaic arrays for enhanced penetration of electric field to permit higher-resolution implants. Approach: We developed 3D COMSOL models of subretinal photovoltaic arrays that accurately quantify the device electrodynamics during stimulation and verified it experimentally through comparison with the standard (flat) photovoltaic arrays. The models were then applied to optimise the design of 3D electrode structures (pillars and honeycombs) to efficiently stimulate the inner retinal neurons. The return electrodes elevated on top of the honeycomb walls surrounding each pixel orient the electric field inside the cavities vertically, aligning it with bipolar cells for optimal stimulation. Alternatively, pillars elevate the active electrode into the inner nuclear layer, improving proximity to the target neurons. Modelling results informed a microfabrication process of electroplating the 3D electrode structures on top of the existing flat subretinal prosthesis. Main results: Simulations demonstrate that despite the conductive sidewalls of the 3D electrodes being exposed to electrolyte, most of the charge flows via the high-capacitance sputtered Iridium Oxide film that caps the top of the 3D structures. The 24 µm height of the electroplated honeycomb structures was optimised for integration with the inner nuclear layer cells in rat retina, while 35 µm height of the pillars was optimized for penetrating the debris layer in human patients. Release from the wafer and implantation of the 3D arrays demonstrated that they are mechanically robust to withstand the associated forces. Histology demonstrated successful integration of the 3D structures with the rat retina in-vivo. Significance: Electroplated 3D honeycomb structures produce a vertically oriented electric field that offers low stimulation threshold, high spatial resolution and high contrast for the retinal implants with pixel sizes down to 20µm in width. Pillar electrodes offer an alternative configuration for extending the stimulation past the debris layers. Electroplating of the 3D structures is compatible with the fabrication process of the flat photovoltaic arrays, thereby enabling much more efficient stimulation than in their original flat configuration.

8.
Ann Thorac Surg ; 116(5): 871-907, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37777933

RESUMO

Care and outcomes for the more than 40,000 patients undergoing pediatric and congenital heart surgery in the United States annually are known to vary widely. While consensus recommendations have been published across numerous fields as one mechanism to promote a high level of care delivery across centers, it has been more than two decades since the last pediatric heart surgery recommendations were published in the United States. More recent guidance is lacking, and collaborative efforts involving the many disciplines engaged in caring for these children have not been undertaken to date. The present initiative brings together professional societies spanning numerous care domains and congenital cardiac surgeons, pediatric cardiologists, nursing, and other healthcare professionals from diverse programs around the country to develop consensus recommendations for United States centers. The focus of this initial work is on pediatric heart surgery, and it is recommended that future efforts focus in detail on the adult congenital population. We describe the background, rationale, and methodology related to this collaborative effort, and recommendations put forth for Essential Care Centers (essential services necessary for any program), and Comprehensive Care Centers (services to optimize comprehensive and high-complexity care), encompassing structure, process, and outcome metrics across 14 domains.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cardiopatias Congênitas , Adulto , Humanos , Criança , Estados Unidos , Cardiopatias Congênitas/cirurgia , Cardiopatias Congênitas/etiologia , Procedimentos Cirúrgicos Cardíacos/métodos , Atenção à Saúde
9.
J Thorac Cardiovasc Surg ; 166(6): 1782-1820, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37777958

RESUMO

Care and outcomes for the more than 40,000 patients undergoing pediatric and congenital heart surgery in the United States annually are known to vary widely. While consensus recommendations have been published across numerous fields as one mechanism to promote a high level of care delivery across centers, it has been more than two decades since the last pediatric heart surgery recommendations were published in the United States. More recent guidance is lacking, and collaborative efforts involving the many disciplines engaged in caring for these children have not been undertaken to date. The present initiative brings together professional societies spanning numerous care domains and congenital cardiac surgeons, pediatric cardiologists, nursing, and other healthcare professionals from diverse programs around the country to develop consensus recommendations for United States centers. The focus of this initial work is on pediatric heart surgery, and it is recommended that future efforts focus in detail on the adult congenital population. We describe the background, rationale, and methodology related to this collaborative effort, and recommendations put forth for Essential Care Centers (essential services necessary for any program), and Comprehensive Care Centers (services to optimize comprehensive and high-complexity care), encompassing structure, process, and outcome metrics across 14 domains.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cardiopatias Congênitas , Adulto , Humanos , Criança , Estados Unidos , Cardiopatias Congênitas/cirurgia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Atenção à Saúde , Consenso
10.
Proc Natl Acad Sci U S A ; 120(42): e2307380120, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37831740

RESUMO

In patients blinded by geographic atrophy, a subretinal photovoltaic implant with 100 µm pixels provided visual acuity closely matching the pixel pitch. However, such flat bipolar pixels cannot be scaled below 75 µm, limiting the attainable visual acuity. This limitation can be overcome by shaping the electric field with 3-dimensional (3-D) electrodes. In particular, elevating the return electrode on top of the honeycomb-shaped vertical walls surrounding each pixel extends the electric field vertically and decouples its penetration into tissue from the pixel width. This approach relies on migration of the retinal cells into the honeycomb wells. Here, we demonstrate that majority of the inner retinal neurons migrate into the 25 µm deep wells, leaving the third-order neurons, such as amacrine and ganglion cells, outside. This enables selective stimulation of the second-order neurons inside the wells, thus preserving the intraretinal signal processing in prosthetic vision. Comparable glial response to that with flat implants suggests that migration and separation of the retinal cells by the walls does not cause additional stress. Furthermore, retinal migration into the honeycombs does not negatively affect its electrical excitability, while grating acuity matches the pixel pitch down to 40 µm and reaches the 27 µm limit of natural resolution in rats with 20 µm pixels. These findings pave the way for 3-D subretinal prostheses with pixel sizes of cellular dimensions.


Assuntos
Poríferos , Neurônios Retinianos , Próteses Visuais , Humanos , Ratos , Animais , Implantação de Prótese , Retina/fisiologia , Visão Ocular , Estimulação Elétrica
11.
World J Pediatr Congenit Heart Surg ; 14(5): 642-679, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37737602

RESUMO

Care and outcomes for the more than 40,000 patients undergoing pediatric and congenital heart surgery in the United States annually are known to vary widely. While consensus recommendations have been published across numerous fields as one mechanism to promote a high level of care delivery across centers, it has been more than two decades since the last pediatric heart surgery recommendations were published in the United States. More recent guidance is lacking, and collaborative efforts involving the many disciplines engaged in caring for these children have not been undertaken to date. The present initiative brings together professional societies spanning numerous care domains and congenital cardiac surgeons, pediatric cardiologists, nursing, and other healthcare professionals from diverse programs around the country to develop consensus recommendations for United States centers. The focus of this initial work is on pediatric heart surgery, and it is recommended that future efforts focus in detail on the adult congenital population. We describe the background, rationale, and methodology related to this collaborative effort, and recommendations put forth for Essential Care Centers (essential services necessary for any program), and Comprehensive Care Centers (services to optimize comprehensive and high-complexity care), encompassing structure, process, and outcome metrics across 14 domains.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cirurgiões , Adulto , Humanos , Criança , Coração
12.
Health Care Manag Sci ; 26(4): 692-718, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37665543

RESUMO

Using data from cardiovascular surgery patients with long and highly variable post-surgical lengths of stay (LOS), we develop a modeling framework to reduce recovery unit congestion. We estimate the LOS and its probability distribution using machine learning models, schedule procedures on a rolling basis using a variety of optimization models, and estimate performance with simulation. The machine learning models achieved only modest LOS prediction accuracy, despite access to a very rich set of patient characteristics. Compared to the current paper-based system used in the hospital, most optimization models failed to reduce congestion without increasing wait times for surgery. A conservative stochastic optimization with sufficient sampling to capture the long tail of the LOS distribution outperformed the current manual process and other stochastic and robust optimization approaches. These results highlight the perils of using oversimplified distributional models of LOS for scheduling procedures and the importance of using optimization methods well-suited to dealing with long-tailed behavior.


Assuntos
Hospitais , Aprendizado de Máquina , Humanos , Simulação por Computador , Tempo de Internação , Atenção à Saúde
13.
bioRxiv ; 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37546938

RESUMO

Several genetic risk factors for Alzheimer's Disease (AD) implicate genes involved in lipid metabolism and many of these lipid genes are highly expressed in glial cells. However, the relationship between lipid metabolism in glia and AD pathology remains poorly understood. Through single-nucleus RNA-sequencing of AD brain tissue, we have identified a microglial state defined by the expression of the lipid droplet (LD) associated enzyme ACSL1 with ACSL1-positive microglia most abundant in AD patients with the APOE4/4 genotype. In human iPSC-derived microglia (iMG) fibrillar Aß (fAß) induces ACSL1 expression, triglyceride synthesis, and LD accumulation in an APOE-dependent manner. Additionally, conditioned media from LD-containing microglia leads to Tau phosphorylation and neurotoxicity in an APOE-dependent manner. Our findings suggest a link between genetic risk factors for AD with microglial LD accumulation and neurotoxic microglial-derived factors, potentially providing novel therapeutic strategies for AD.

14.
bioRxiv ; 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37546971

RESUMO

Photovoltaic subretinal prosthesis (PRIMA) enables restoration of sight via electrical stimulation of the interneurons in degenerated retina, with resolution limited by the 100 µm pixel size. Since decreasing the pixel size below 75 µm in the current bipolar geometry is impossible, we explore the possibility of using smaller pixels based on a novel 3-dimensional honeycomb-shaped design. We assessed the long-term biocompatibility and stability of these arrays in rats by investigating the anatomical integration of the retina with flat and 3D implants and response to electrical stimulation over lifetime - up to 9 months post-implantation in aged rats. With both flat and 3D implants, VEP amplitude decreased after the day of implantation by more than 3-fold, and gradually recovered over about 3 months. With 25 µm high honeycomb walls, the majority of bipolar cells migrate into the wells, while amacrine and ganglion cells remain above the cavities, which is essential for selective network-mediated stimulation of the second-order neurons. Retinal thickness and full-field stimulation threshold with 40 µm-wide honeycomb pixels were comparable to those with planar devices - 0.05 mW/mm2 with 10ms pulses. However, fewer cells from the inner nuclear layer migrated into the 20 µm-wide wells, and stimulation threshold increased over 5 months, before stabilizing at about 0.08 mW/mm2. Such threshold is significantly lower than 1.8 mW/mm2 with a previous design of flat bipolar pixels, confirming the promise of the 3D honeycomb-based approach to high resolution subretinal prosthesis.

15.
J Endourol ; 37(9): 1049-1056, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37493542

RESUMO

Introduction: The metal-based Resonance stent (RS) has traditionally been placed in patients with malignant ureteral obstruction; as such, the long-term utility of RS among patients with benign ureteral obstruction (BUO) remains underinvestigated. Methods: We retrospectively reviewed our database for patients with BUO who underwent RS placement between 2010 and 2020. The impact of chronic RS placement on renal function was evaluated by estimated serum creatinine-based glomerular filtration rate (eGFR), furosemide renal scan, and CT-based renal parenchymal volume measurement. The number of and reason for RS stent exchanges during the follow-up period, incidence of encrustation, and the average indwell time were recorded. A cost analysis of placing the RS vs a polymeric stent was performed. Results: Among 43 RS patients with BUO, at a mean follow-up of 26 months, there was no change in eGFR (p = 0.99), parenchymal volume (p = 0.44), or split renal function of the stent-bearing side on renal scan (p = 0.48). The mean RS indwell time was 9.7 months. Eleven patients (26%) underwent premature stent replacement (6 cases) or removal (5 cases). Stents in 9 patients (32%) were encrusted, of which 4 (44%) required laser lithotripsy. Overall, 25 patients (58%) and 12 patients (28%) had a mean stent indwell time of ≥6 months and ≥12 months, respectively. Placing an RS resulted in a 52%, 37%, and 5.6% cost reduction compared with a regular polymeric stent placement, where it was exchanged every 6, 4, or 3 months, respectively. Conclusions: RS deployment in the patient with a BUO results in cost-effective maintenance of renal function and of renal parenchymal volume at a mean follow-up of 2 years; however, only 28% of patients fulfilled the 1-year criterion for RS indwell time.


Assuntos
Ureter , Obstrução Ureteral , Humanos , Obstrução Ureteral/etiologia , Estudos Retrospectivos , Rim/fisiologia , Stents/efeitos adversos
16.
ArXiv ; 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37205266

RESUMO

Queries with similar information needs tend to have similar document clicks, especially in biomedical literature search engines where queries are generally short and top documents account for most of the total clicks. Motivated by this, we present a novel architecture for biomedical literature search, namely Log-Augmented DEnse Retrieval (LADER), which is a simple plug-in module that augments a dense retriever with the click logs retrieved from similar training queries. Specifically, LADER finds both similar documents and queries to the given query by a dense retriever. Then, LADER scores relevant (clicked) documents of similar queries weighted by their similarity to the input query. The final document scores by LADER are the average of (1) the document similarity scores from the dense retriever and (2) the aggregated document scores from the click logs of similar queries. Despite its simplicity, LADER achieves new state-of-the-art (SOTA) performance on TripClick, a recently released benchmark for biomedical literature retrieval. On the frequent ("HEAD") queries, LADER largely outperforms the best retrieval model by 39% relative NDCG@10 (0.338 v.s. 0.243). LADER also achieves better performance on the less frequent ("TORSO") queries with 11% relative NDCG@10 improvement over the previous SOTA (0.303 v.s. 0.272). On the rare ("TAIL") queries where similar queries are scarce, LADER still compares favorably to the previous SOTA method (NDCG@10: 0.310 v.s. 0.295). On all queries, LADER can improve the performance of a dense retriever by 24%-37% relative NDCG@10 while not requiring additional training, and further performance improvement is expected from more logs. Our regression analysis has shown that queries that are more frequent, have higher entropy of query similarity and lower entropy of document similarity, tend to benefit more from log augmentation.

17.
Nutrients ; 15(7)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37049555

RESUMO

Type 2 diabetes (T2D) is a challenging health concern worldwide. A lifestyle intervention to treat T2D is difficult to adhere, and the effectiveness of approved medications such as metformin, thiazolidinediones (TZDs), and sulfonylureas are suboptimal. On the other hand, bariatric procedures such as Roux-en-Y gastric bypass (RYGB) are being recognized for their remarkable ability to achieve diabetes remission, although the underlying mechanism is not clear. Recent evidence points to branched-chain amino acids (BCAAs) as a potential contributor to glucose impairment and insulin resistance. RYGB has been shown to effectively lower plasma BCAAs in insulin-resistant or T2D patients that may help improve glycemic control, but the underlying mechanism for BCAA reduction is not understood. Hence, we attempted to explore the mechanism by which RYGB reduces BCAAs. To this end, we randomized diet-induced obese (DIO) mice into three groups that underwent either sham or RYGB surgery or food restriction to match the weight of RYGB mice. We also included regular chow-diet-fed healthy mice as an additional control group. Here, we show that compared to sham surgery, RYGB in DIO mice markedly lowered serum BCAAs most likely by rescuing BCAA breakdown in both liver and white adipose tissues. Importantly, the restored BCAA metabolism following RYGB was independent of caloric intake. Fasting insulin and HOMA-IR were decreased as expected, and serum valine was strongly associated with insulin resistance. While gut hormones such as glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) are postulated to mediate various surgery-induced metabolic benefits, mice lacking these hormonal signals (GLP-1R/Y2R double KO) were still able to effectively lower plasma BCAAs and improve glucose tolerance, similar to mice with intact GLP-1 and PYY signaling. On the other hand, mice deficient in fibroblast growth factor 21 (FGF21), another candidate hormone implicated in enhanced glucoregulatory action following RYGB, failed to decrease plasma BCAAs and normalize hepatic BCAA degradation following surgery. This is the first study using an animal model to successfully recapitulate the RYGB-led reduction of circulating BCAAs observed in humans. Our findings unmasked a critical role of FGF21 in mediating the rescue of BCAA metabolism following surgery. It would be interesting to explore the possibility of whether RYGB-induced improvement in glucose homeostasis is partly through decreased BCAAs.


Assuntos
Diabetes Mellitus Tipo 2 , Derivação Gástrica , Resistência à Insulina , Humanos , Camundongos , Animais , Obesidade/metabolismo , Diabetes Mellitus Tipo 2/complicações , Aminoácidos de Cadeia Ramificada , Insulina , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Glucose , Glicemia/metabolismo
18.
Sci Data ; 10(1): 124, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36882443

RESUMO

WAVES is a large, single-center dataset comprising 9 years of high-frequency physiological waveform data from patients in intensive and acute care units at a large academic, pediatric medical center. The data comprise approximately 10.6 million hours of 1 to 20 concurrent waveforms over approximately 50,364 distinct patient encounters. The data have been de-identified, cleaned, and organized to facilitate research. Initial analyses demonstrate the potential of the data for clinical applications such as non-invasive blood pressure monitoring and methodological applications such as waveform-agnostic data imputation. WAVES is the largest pediatric-focused and second largest physiological waveform dataset available for research.


Assuntos
Cuidados Críticos , Hospitais , Criança , Humanos
19.
Crit Care Med ; 51(6): 787-796, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36920081

RESUMO

OBJECTIVES: Identifying modifiable risk factors associated with central line-associated bloodstream infections (CLABSIs) may lead to modifications to central line (CL) management. We hypothesize that the number of CL accesses per day is associated with an increased risk for CLABSI and that a significant fraction of CL access may be substituted with non-CL routes. DESIGN: We conducted a retrospective cohort study of patients with at least one CL device day from January 1, 2015, to December 31, 2019. A multivariate mixed-effects logistic regression model was used to estimate the association between the number of CL accesses in a given CL device day and prevalence of CLABSI within the following 3 days. SETTING: A 395-bed pediatric academic medical center. PATIENTS: Patients with at least one CL device day from January 1, 2015, to December 31, 2019. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: There were 138,411 eligible CL device days across 6,543 patients, with 639 device days within 3 days of a CLABSI (a total of 217 CLABSIs). The number of per-day CL accesses was independently associated with risk of CLABSI in the next 3 days (adjusted odds ratio, 1.007; 95% CI, 1.003-1.012; p = 0.002). Of medications administered through CLs, 88% were candidates for delivery through a peripheral line. On average, these accesses contributed a 6.3% increase in daily risk for CLABSI. CONCLUSIONS: The number of daily CL accesses is independently associated with risk of CLABSI in the next 3 days. In the pediatric population examined, most medications delivered through CLs could be safely administered peripherally. Efforts to reduce CL access may be an important strategy to include in contemporary CLABSI-prevention bundles.


Assuntos
Bacteriemia , Infecções Relacionadas a Cateter , Cateterismo Venoso Central , Cateteres Venosos Centrais , Humanos , Criança , Infecções Relacionadas a Cateter/etiologia , Estudos Retrospectivos , Cateterismo Venoso Central/efeitos adversos , Bacteriemia/epidemiologia , Bacteriemia/etiologia , Cateteres Venosos Centrais/efeitos adversos
20.
Antioxidants (Basel) ; 12(2)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36829974

RESUMO

Alzheimer's disease (AD) is the most common type of dementia that affects millions of individuals worldwide. It is an irreversible neurodegenerative disorder that is characterized by memory loss, impaired learning and thinking, and difficulty in performing regular daily activities. Despite nearly two decades of collective efforts to develop novel medications that can prevent or halt the disease progression, we remain faced with only a few options with limited effectiveness. There has been a recent growth of interest in the role of nutrition in brain health as we begin to gain a better understanding of what and how nutrients affect hormonal and neural actions that not only can lead to typical cardiovascular or metabolic diseases but also an array of neurological and psychiatric disorders. Vitamins and minerals, also known as micronutrients, are elements that are indispensable for functions including nutrient metabolism, immune surveillance, cell development, neurotransmission, and antioxidant and anti-inflammatory properties. In this review, we provide an overview on some of the most common vitamins and minerals and discuss what current studies have revealed on the link between these essential micronutrients and cognitive performance or AD.

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