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1.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(6): 631-638, 2024 Jun 15.
Artículo en Zh | MEDLINE | ID: mdl-38926381

RESUMEN

OBJECTIVES: To observe the effects of melatonin on autophagy in cortical neurons of neonatal rats with hypoxic-ischemic brain damage (HIBD) and to explore its mechanisms via the PI3K/AKT signaling pathway, aiming to provide a basis for the clinical application of melatonin. METHODS: Seven-day-old Sprague-Dawley neonatal rats were randomly divided into a sham operation group, an HIBD group, and a melatonin group (n=9 each). The neonatal rat HIBD model was established using the classic Rice-Vannucci method. Neuronal morphology in the neonatal rat cerebral cortex was observed with hematoxylin-eosin staining and Nissl staining. Autophagy-related protein levels of microtubule-associated protein 1 light chain 3 (LC3) and Beclin-1 were detected by immunofluorescence staining and Western blot analysis. Phosphorylated phosphoinositide 3-kinase (p-PI3K) and phosphorylated protein kinase B (p-AKT) protein expression levels were measured by immunohistochemistry and Western blot. The correlation between autophagy and the PI3K pathway in the melatonin group and the HIBD group was analyzed using Pearson correlation analysis. RESULTS: Twenty-four hours post-modeling, neurons in the sham operation group displayed normal size and orderly arrangement. In contrast, neurons in the HIBD group showed swelling and disorderly arrangement, while those in the melatonin group had relatively normal morphology and more orderly arrangement. Nissl bodies were normal in the sham operation group but distorted in the HIBD group; however, they remained relatively intact in the melatonin group. The average fluorescence intensity of LC3 and Beclin-1 was higher in the HIBD group compared to the sham operation group, but was reduced in the melatonin group compared to the HIBD group (P<0.05). The number of p-PI3K+ and p-AKT+ cells decreased in the HIBD group compared to the sham operation group but increased in the melatonin group compared to the HIBD group (P<0.05). LC3 and Beclin-1 protein expression levels were higher, and p-PI3K and p-AKT levels were lower in the HIBD group compared to the sham operation group (P<0.05); however, in the melatonin group, LC3 and Beclin-1 levels decreased, and p-PI3K and p-AKT increased compared to the HIBD group (P<0.05). The correlation analysis results showed that the difference of the mean fluorescence intensity of LC3 and Beclin-1 protein in the injured cerebral cortex between the melatonin and HIBD groups was negatively correlated with the difference of the number of p-PI3K+ and p-AKT+ cells between the two groups (P<0.05). CONCLUSIONS: Melatonin can inhibit excessive autophagy in cortical neurons of neonatal rats with HIBD, thereby alleviating HIBD. This mechanism is associated with the PI3K/AKT pathway.


Asunto(s)
Animales Recién Nacidos , Autofagia , Corteza Cerebral , Hipoxia-Isquemia Encefálica , Melatonina , Neuronas , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Ratas Sprague-Dawley , Transducción de Señal , Animales , Melatonina/farmacología , Hipoxia-Isquemia Encefálica/patología , Hipoxia-Isquemia Encefálica/metabolismo , Ratas , Proteínas Proto-Oncogénicas c-akt/metabolismo , Corteza Cerebral/patología , Autofagia/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Neuronas/patología , Neuronas/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Masculino , Femenino
2.
Clin Gastroenterol Hepatol ; 18(7): 1567-1575.e2, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31712075

RESUMEN

BACKGROUND & AIMS: Few studies have compared regional differences in acute pancreatitis. We analyzed data from an international registry of patients with acute pancreatitis to evaluate geographic variations in patient characteristics, management, and outcomes. METHODS: We collected data from the APPRENTICE registry of patients with acute pancreatitis, which obtains information from patients in Europe (6 centers), India (3 centers), Latin America (5 centers), and North America (8 centers) using standardized questionnaires. Our final analysis included 1612 patients with acute pancreatitis (median age, 49 years; 53% male, 62% white) enrolled from August 2015 through January 2018. RESULTS: Biliary (45%) and alcoholic acute pancreatitis (21%) were the most common etiologies. Based on the revised Atlanta classification, 65% of patients developed mild disease, 23% moderate, and 12% severe. The mean age of patients in Europe (58 years) was older than mean age for all 4 regions (46 years) and a higher proportion of patients in Europe had comorbid conditions (73% vs 50% overall). The predominant etiology of acute pancreatitis in Latin America was biliary (78%), whereas alcohol-associated pancreatitis accounted for the highest proportion of acute pancreatitis cases in India (45%). Pain was managed with opioid analgesics in 93% of patients in North America versus 27% of patients in the other 3 regions. Cholecystectomies were performed at the time of hospital admission for most patients in Latin America (60% vs 15% overall). A higher proportion of European patients with severe acute pancreatitis died during the original hospital stay (44%) compared with the other 3 regions (15%). CONCLUSIONS: We found significant variation in demographics, etiologies, management practices, and outcomes of acute pancreatitis worldwide. ClinicalTrials.gov number: NCT03075618.


Asunto(s)
Pancreatitis , Enfermedad Aguda , Demografía , Femenino , Hospitalización , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Pancreatitis/epidemiología , Pancreatitis/terapia
3.
J Stroke Cerebrovasc Dis ; 29(5): 104711, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32184023

RESUMEN

BACKGROUND AND PURPOSE: Perioperative stroke remains a devastating complication after cardiac surgery and is associated with significant morbidity and mortality. Despite the significant contribution of stroke to perioperative mortality, risk factors for perioperative stroke-related mortality have not been well characterized. Our aim was to identify independent predictors of perioperative stroke-related mortality after cardiac surgery, using the Pennsylvania Health Care Cost Containment Council (PHC4) database which provides information on cause of death. METHODS: We retrospectively examined patient medical records from 2012 to 2014 of 3345 patients (ages 18-99) who underwent a cardiac surgical procedure and suffered perioperative (30-day) mortality. Perioperative stroke-related mortality was identified by International Classification of Diseases, Tenth Revision, Clinical Modification cause of death codes. We performed Fisher's exact test and multivariate analysis to identify comorbidities that independently predict perioperative stroke-related mortality. RESULTS: After controlling for all variables with multivariate analysis, we found that patients with carotid stenosis were 4.9 (adjusted odds ratio [aOR], 95% confidence interval [CI] 1.8-12.8) times more likely to die from a stroke than from other causes, when compared to patients without carotid stenosis. Other independent predictors of perioperative stroke-related mortality included in-hospital stroke (aOR 108.8, 95%CI 48.2-245.9), history of stroke (aOR 17.1, 95%CI 3.3-88.4), and age ≥ 80 (aOR 4.9, 95%CI 2.1-11.2). CONCLUSIONS: This is the first study to establish carotid stenosis, among other comorbidities, as an independent predictor of perioperative stroke-related mortality after cardiac surgery. Understanding risk factors for mortality from stroke will help enhance the efficacy of preoperative screening, intraoperative neurophysiological monitoring, and potential treatments for stroke. Interventions to manage carotid stenosis and other identified risk factors prior to, during, or immediately after surgery may have the potential to reduce perioperative stroke-related mortality after cardiac surgery.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/mortalidad , Accidente Cerebrovascular/mortalidad , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Estenosis Carotídea/mortalidad , Comorbilidad , Bases de Datos Factuales , Femenino , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Pennsylvania/epidemiología , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/diagnóstico , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
4.
Crit Care Med ; 47(4): e292-e300, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30855329

RESUMEN

OBJECTIVES: Brain mitochondrial dysfunction limits neurologic recovery after cardiac arrest. Brain polyunsaturated cardiolipins, mitochondria-unique and functionally essential phospholipids, have unprecedented diversification. Since brain cardiolipins are not present in plasma normally, we hypothesized their appearance would correlate with brain injury severity early after cardiac arrest and return of spontaneous circulation. DESIGN: Observational case-control study. SETTING: Two medical centers within one city. PARTICIPANTS (SUBJECTS): We enrolled 41 adult cardiac arrest patients in whom blood could be obtained within 6 hours of resuscitation. Two subjects were excluded following outlier analysis. Ten healthy subjects were controls. Sprague-Dawley rats were used in asphyxial cardiac arrest studies. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We developed a high-resolution liquid chromatography/mass spectrometry method and determined cardiolipins speciation in human brain, heart, and plasma within 6 hours of (return of spontaneous circulation) from 39 patients with cardiac arrest, 5 with myocardial infarction, and 10 healthy controls. Cerebral score was derived from brain-specific cardiolipins identified in plasma of patients with varying neurologic injury and outcome. Using a rat model of cardiac arrest, cardiolipins were quantified in plasma, brain, and heart. Human brain exhibited a highly diverse cardiolipinome compared with heart that allowed the identification of brain-specific cardiolipins. Nine of 26 brain-specific cardiolipins were detected in plasma and correlated with brain injury. The cerebral score correlated with early neurologic injury and predicted discharge neurologic/functional outcome. Cardiolipin (70:5) emerged as a potential point-of-care marker predicting injury severity and outcome. In rat cardiac arrest, a significant reduction in hippocampal cardiolipins corresponded to their release from the brain into systemic circulation. Cerebral score was significantly increased in 10 minutes versus 5 minutes no-flow cardiac arrest and naïve controls. CONCLUSIONS: Brain-specific cardiolipins accumulate in plasma early after return of spontaneous circulation and proportional to neurologic injury representing a promising novel biomarker.


Asunto(s)
Lesiones Encefálicas/metabolismo , Cardiolipinas/sangre , Cardiomiopatías/metabolismo , Mitocondrias Cardíacas/metabolismo , Animales , Reanimación Cardiopulmonar/métodos , Estudios de Casos y Controles , Femenino , Cromatografía de Gases y Espectrometría de Masas/métodos , Paro Cardíaco/metabolismo , Humanos , Masculino , Oxidación-Reducción , Ratas , Ratas Sprague-Dawley
5.
Small ; 14(41): e1802443, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30175545

RESUMEN

Being conductive and flexible, 2D transition metal nitrides and carbides (MXenes) can serve in Li-S batteries as sulfur hosts to increase the conductivity and alleviate the volume expansion. However, the surface functional groups, such as OH and F, weaken the ability of bare MXenes in the chemisorption of polysulfides. Besides, they create numerous hydrogen bonds which make MXenes liable to restack, resulting in substantial loss of active area and, thus, inaccessibility of ions and electrolyte. Herein, a facile, one-step strategy is developed for the growth of TiO2 quantum dots (QDs) on ultrathin MXene (Ti3 C2 Tx ) nanosheets by cetyltrimethylammonium bromide-assisted solvothermal synthesis. These QDs act as spacers to isolate the MXene nanosheets from restacking, and preserve their 2D geometry which guarantees larger electrode-electrolyte contact area and higher sulfur loading. The stronger adsorption energy of polysulfides with TiO2 (than with Ti3 C2 Tx ), as proven by density functional theory calculations, is essential for better on-site polysulfide retention. The ultrathin nature and protected conductivity ensure rapid ion and electron diffusion, and the excellent flexibility maintains high mechanical integrity. In result, the TiO2 QDs@MXene/S cathode exhibits significantly improved long-term cyclability and rate capability, disclosing a new opportunity toward fast and stable Li-S batteries.

6.
Am J Geriatr Psychiatry ; 26(7): 765-777, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29724663

RESUMEN

OBJECTIVE: Testing stepped-care approaches that address both depression and low back pain are needed to optimize outcomes in older adults. METHODS: This university-based late-life depression research center assessed 227 adults aged ≥ 60 years with chronic low back pain and depression. In Phase 1 participants received 6 weeks of low-dose venlafaxine (≤150 mg/day). Nonresponders were randomized to 10 weeks of high-dose venlafaxine (up to 300 mg/day) plus problem-solving therapy (PST) or high-dose venlafaxine with supportive management. Definition of response was 2 weeks of Patient Health Questionnaire-9 ≤ 5 and ≥30% pain reduction on a numeric rating scale. Function was measured with the Short Physical Performance Battery (SPPB) and Roland Morris Disability Questionnaire (RMDQ). RESULTS: Of those who completed Phase 1 (N = 209), 78.5% (N = 164) were nonresponders and 139 proceeded to Phase 2, with 68 randomized to venlafaxine/PST and 71 randomized to venlafaxine/supportive management. Of those in venlafaxine/PST, 41.2% (28/68) responded, and of those in venlafaxine/supportive management, 39.4% (28/71) responded. Cumulative proportion responding over time did not differ across the two arms (hazard ratio: 1.07; 95% confidence interval: 0.63-1.80). We observed clinically significant improvements in physical performance (SPPB) and disability (RMDQ) across both Phase 1 and 2, independent of intervention. Over 12 months of follow-up there was no difference between groups for stability of depression, pain, or disability. CONCLUSION: The combination of antidepressant pharmacotherapy and PST was not superior to antidepressant pharmacotherapy and supportive management. Clinically, the rates of response and stability of response over 1 year observed in both groups suggest that these approaches may have clinical utility in these chronically suffering patients.


Asunto(s)
Antidepresivos/uso terapéutico , Depresión/tratamiento farmacológico , Depresión/terapia , Dolor de la Región Lumbar/terapia , Solución de Problemas , Psicoterapia/métodos , Anciano , Anciano de 80 o más Años , Antidepresivos/efectos adversos , Terapia Combinada , Depresión/complicaciones , Femenino , Humanos , Dolor de la Región Lumbar/complicaciones , Dolor de la Región Lumbar/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Clorhidrato de Venlafaxina/uso terapéutico
7.
J Appl Gerontol ; : 7334648241229574, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38298084

RESUMEN

This study examines when and why unpaid caregivers use respite services. We conducted a secondary analysis of the 2017 National Study of Caregiving (NSOC) Wave III, a U.S. nationally representative sample comprising 2652 unpaid caregivers. We found that unpaid caregivers reporting financial, physical, and emotional difficulties in caregiving were more likely to use respite care services than those not reporting these challenges. White, non-Hispanic caregivers reporting that they received support from their social networks (families/friends) were more likely to use respite care services than non-White and/or Hispanic caregivers receiving such support. Non-White and/or Hispanic caregivers who belonged to or attended support groups were more likely to use respite care support than those without social group affiliation. Respite care is underutilized in the U.S. despite its value and efficacy in supporting caregivers' mental and physical well-being. Policies are necessary to increase availability and access to respite services for diverse unpaid caregivers.

8.
Nanoscale ; 16(23): 11005-11018, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38774955

RESUMEN

Lithium-sulfur batteries (Li-S batteries) are being widely studied as promising energy-storage solutions for the next generation owing to their excellent properties including high energy density, eco-friendliness, and low cost. Nevertheless, drawbacks, especially the severe "shuttle effect" and slow transformation of polysulfides, hinder the road to commercialization of Li-S batteries. The functional utilization of metal compounds in Li-S batteries has been verified, such as enhancing the conductivity, adsorption of lithium polysulfides (LPSs) and improving the kinetics of electrode processes. Benefiting from the outstanding catalytic capability and relatively good conductivity, metal phosphides have gradually received intense attention over the past few years. Consequently, significant progress has been achieved in the optimization of phosphides for Li-S batteries in recent years. This review introduces the application of metal phosphides in Li-S batteries from the aspects of their own characteristics, material structure design, and material interface control. The aim of this review is to enhance the understanding of the operational mechanism of metal phosphides and provide guidance for the development of Li-S batteries.

9.
Disabil Rehabil ; : 1-7, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38327137

RESUMEN

PURPOSE: People with spinal cord injury (PwSCI) can experience life changes, including impacts on their physical and mental health. PwSCI often report less life satisfaction and lower subjective well-being than peers without SCI. These challenges and adversities increase the demand on them to be more resilient. Healthcare providers need quick and valid instruments to assess adult patients' resilience in clinical settings. We aimed to validate the factor validity and discrimination ability of a resilience scale, CD-RISC-10, for clinical usage in adults with SCI during hospitalization. MATERIALS AND METHODS: 93 adults with SCI responded to the self-reported survey, including CD-RISC-10, the Patient Health Questionnaire-9 Scale (PHQ-9), the Satisfaction with Life Scale (SWLS), and the Intrinsic Spirituality Scale. We conducted descriptive statistics, exploratory factor analysis (EFA), and item response theory (IRT). RESULTS: Two items were deleted from CD-RISC-10 after EFA, forming CD-RISC-8. The item discriminations of the remaining eight items from the unconstrained IRT model ranged from a high of 3.071 to a relatively low 1.433. CD-RISC-8 is significantly related to PHQ-9 and SWLS. CONCLUSIONS: The factor validity of the CD-RISC-8 was improved. Significantly, the CD-RISC-8 has excellent potential for clinical usage due to its discriminant ability between low and intermediate resilience.


Spinal Cord InjuryPeople with spinal cord injury (PwSCI) experience unique challenges and adversities that can negatively affect physical, mental, social, and financial health and life satisfaction.PwSCI with higher resilience adapt to challenges quicker, and have better mental health outcomes and improved quality of life.The CD-RISC-8 is useful for screening PwSCI who need resilience intervention and it is sensitive enough to evaluate resilience improvement within two minutes.

10.
Commun Biol ; 7(1): 396, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38561411

RESUMEN

Myocardial ischemia-reperfusion injury (MIRI) is involved in the pathogenesis of multiple cardiovascular diseases. This study elucidated the biological function of lysine acetyltransferase 5 (KAT5) in cardiomyocyte pyroptosis during MIRI. Oxygen-glucose deprivation/reoxygenation and left anterior descending coronary artery ligation were used to establish MIRI models. Here we show, KAT5 and STIP1 homology and U-box-containing protein 1 (STUB1) were downregulated, while large tumor suppressor kinase 2 (LATS2) was upregulated in MIRI models. KAT5/STUB1 overexpression or LATS2 silencing repressed cardiomyocyte pyroptosis. Mechanistically, KAT5 promoted STUB1 transcription via acetylation modulation, and subsequently caused ubiquitination and degradation of LATS2, which activated YAP/ß-catenin pathway. Notably, the inhibitory effect of STUB1 overexpression on cardiomyocyte pyroptosis was abolished by LATS2 overexpression or KAT5 depletion. Our findings suggest that KAT5 overexpression inhibits NLRP3-mediated cardiomyocyte pyroptosis to relieve MIRI through modulation of STUB1/LATS2/YAP/ß-catenin axis, providing a potential therapeutic target for MIRI.


Asunto(s)
Daño por Reperfusión Miocárdica , beta Catenina , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Miocitos Cardíacos/metabolismo , Piroptosis , Ubiquitinación , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Lisina Acetiltransferasa 5/metabolismo
11.
Neural Netw ; 176: 106354, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38723308

RESUMEN

Neural operators, as a powerful approximation to the non-linear operators between infinite-dimensional function spaces, have proved to be promising in accelerating the solution of partial differential equations (PDE). However, it requires a large amount of simulated data, which can be costly to collect. This can be avoided by learning physics from the physics-constrained loss, which we refer to it as mean squared residual (MSR) loss constructed by the discretized PDE. We investigate the physical information in the MSR loss, which we called long-range entanglements, and identify the challenge that the neural network requires the capacity to model the long-range entanglements in the spatial domain of the PDE, whose patterns vary in different PDEs. To tackle the challenge, we propose LordNet, a tunable and efficient neural network for modeling various entanglements. Inspired by the traditional solvers, LordNet models the long-range entanglements with a series of matrix multiplications, which can be seen as the low-rank approximation to the general fully-connected layers and extracts the dominant pattern with reduced computational cost. The experiments on solving Poisson's equation and (2D and 3D) Navier-Stokes equation demonstrate that the long-range entanglements from the MSR loss can be well modeled by the LordNet, yielding better accuracy and generalization ability than other neural networks. The results show that the Lordnet can be 40× faster than traditional PDE solvers. In addition, LordNet outperforms other modern neural network architectures in accuracy and efficiency with the smallest parameter size.


Asunto(s)
Redes Neurales de la Computación , Simulación por Computador , Algoritmos , Dinámicas no Lineales
12.
Brain Res ; 1822: 148640, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37863169

RESUMEN

Previous studies have showed that the permeability of blood brain barrier (BBB) increased after hypoxia ischemia (HI). The current research uncovered the mechanism of altered BBB permeability after hypoxic-ischemic brain damage (HIBD) through AKT/GSK-3ß/CREB signaling pathway in neonatal rats. Firstly, Magnetic resonance imaging (MRI) combined with hematoxylin-eosin (H&E) staining was used to assess brain injury. Initial findings showed abnormal signals in T2-weighted imaging (T2WI) and diffusion weighted imaging (DWI). Changes also happened in the morphology of nerve cells. Subsequently, we found that BBB damage is manifested as leakage of immunoglobulin G (IgG) and destruction of BBB-related proteins and ultrastructure. Meanwhile, the levels of matrix metalloproteinase-9 (MMP-9) significantly increased at 24 h after HIBD compared to a series of time points. Additionally, immunohistochemical (IHC) staining combined with Western blot (WB) was used to verify the function of the AKT/GSK-3ß/CREB signaling pathway in BBB damage after HI in neonatal rats. Results showed that less Claudin-5, ZO-1, p-AKT, p-GSK-3ß and p-CREB, along with more MMP-9 protein expression were visible on the damaged side of the cerebral cortex in the HIBD group in contrast to the sham and HIBD + SC79 groups. Together, our findings demonstrated that HI in neonatal rats might upregulate the levels of MMP-9 protein and downregulate the levels of Claudin-5 and ZO-1 by inhibiting the AKT/GSK-3ß/CREB pathway, thus disrupting the BBB, which in turn aggravates brain damage after HI in neonatal rats.


Asunto(s)
Barrera Hematoencefálica , Hipoxia-Isquemia Encefálica , Animales , Ratas , Animales Recién Nacidos , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Claudina-5/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Hipoxia-Isquemia Encefálica/metabolismo , Isquemia/complicaciones , Isquemia/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas Sprague-Dawley , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo
13.
Front Microbiol ; 14: 1113157, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37007478

RESUMEN

The decoupling of microbial functional and taxonomic components refers to the phenomenon that a drastic change in microbial taxonomic composition leads to no or only a gentle change in functional composition. Although many studies have identified this phenomenon, the mechanisms underlying it are still unclear. Here we demonstrate, using metagenomics data from a steppe grassland soil under different grazing and phosphorus addition treatments, that there is no "decoupling" in the variation of taxonomic and metabolic functional composition of the microbial community within functional groups at species level. In contrast, the high consistency and complementarity between the abundance and functional gene diversity of two dominant species made metabolic functions unaffected by grazing and phosphorus addition. This complementarity between the two dominant species shapes a bistability pattern that differs from functional redundancy in that only two species cannot form observable redundancy in a large microbial community. In other words, the "monopoly" of metabolic functions by the two most abundant species leads to the disappearance of functional redundancy. Our findings imply that for soil microbial communities, the impact of species identity on metabolic functions is much greater than that of species diversity, and it is more important to monitor the dynamics of key dominant microorganisms for accurately predicting the changes in the metabolic functions of the ecosystems.

14.
Physiol Rep ; 11(6): e15638, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36945966

RESUMEN

Regular, moderate exercise modifies the gut microbiome and contributes to human metabolic and immune health. The microbiome may exert influence on host physiology through the microbial production and modification of metabolites (xenometabolites); however, this has not been extensively explored. We hypothesized that 6 weeks of supervised, aerobic exercise 3×/week (60%-75% heart rate reserve [HRR], 30-60 min) in previously sedentary, lean (n = 14) and obese (n = 10) adults would modify both the fecal and serum xenometabolome. Serum and fecal samples were collected pre- and post-6 week intervention and analyzed by liquid chromatography/tandem mass spectrometry (LC-MS/MS). Linear mixed models (LMMs) identified multiple fecal and serum xenometabolites responsive to exercise training. Further cluster and pathway analysis revealed that the most prominent xenometabolic shifts occurred within aromatic amino acid (ArAA) metabolic pathways. Fecal and serum ArAA derivatives correlated with body composition (lean mass), markers of insulin sensitivity (insulin, HOMA-IR) and cardiorespiratory fitness ( V ̇ O 2 max $$ \dot{\mathrm{V}}{\mathrm{O}}_{2\max } $$ ), both at baseline and in response to exercise training. Two serum aromatic microbial-derived amino acid metabolites that were upregulated following the exercise intervention, indole-3-lactic acid (ILA: fold change: 1.2, FDR p < 0.05) and 4-hydroxyphenyllactic acid (4-HPLA: fold change: 1.3, FDR p < 0.05), share metabolic pathways within the microbiota and were associated with body composition and markers of insulin sensitivity at baseline and in response to training. These data provide evidence of physiologically relevant shifts in microbial metabolism that occur in response to exercise training, and reinforce the view that host metabolic health influences gut microbiota population and function. Future studies should consider the microbiome and xenometabolome when investigating the health benefits of exercise.


Asunto(s)
Resistencia a la Insulina , Adulto , Humanos , Cromatografía Liquida , Espectrometría de Masas en Tándem , Obesidad/metabolismo , Ejercicio Físico/fisiología
15.
J Commun Disord ; 100: 106280, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36384065

RESUMEN

Introduction Atypical prosodic features have been widely reported in autism spectrum disorder (ASD), primarily in non-tonal language speakers. Nevertheless, the prosodic realizations in autistic people who speak tonal languages were relatively understudied. This study aimed to investigate the acoustic and phonetic patterns at the word-level speech in Mandarin-speaking autistic and typically developing (TD) children at different age ranges. Methods Thirty Mandarin-speaking autistic children (15 three- to five-year-olds and 15 six- to eight-year-olds) were recruited into the ASD group. The TD group consisted of 30 age- and gender-matched children. We employed a picture-naming task to elicit the spontaneous speech production of Mandarin disyllabic words in which tone change processes occur, namely Tone 3 (T3) sandhi and neutral tone (T0). Results The phonetic analysis showed that the ASD group generally could produce typical-like T3 sandhi and T0 in terms of pitch height. However, relative to the TD group, they exhibited flatter pitch contours during T3 sandhi production. Moreover, the acoustic pitch mean of citation tones in the ASD group was also significantly higher, accompanied by more rigid pitch curves in contour tones. In addition, the atypical temporal realization in the ASD group was manifested by the longer duration of T0 and the earlier inflection position of T3. Conclusions Mandarin-speaking autistic children under eight had the phonological ability to produce context-dependent tones based on connected tonal information at the word level. Nevertheless, their phonetic prosodic realization of tone change processes was atypical. Our findings provide evidence of atypical prosody in autistic children who speak tone languages. Clinically, these findings may be attributable to underlying neural differences in autistic children.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Niño , Humanos , Fonética , Habla , Lenguaje
16.
Front Neurorobot ; 16: 715440, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35958683

RESUMEN

Indoor location information is an indispensable parameter for modern intelligent warehouse management and robot navigation. Indoor wireless positioning exhibits large errors due to factors such as indoor non-line-of-sight (NLOS) obstructions. In the present study, the error value under the time of arrival (TOA) algorithm was evaluated, and the trilateral positioning method was optimized to minimize the errors. An optimization algorithm for indoor ultra-wideband (UWB) positioning was designed, which was referred as annealing evolution and clustering fusion optimization algorithm. The algorithm exploited the good local search capability of the simulated annealing algorithm and the good global search capability of the genetic algorithm to optimize cluster analysis. The optimal result from sampled data was quickly determined to achieve effective and accurate positioning. These features reduced the non-direct aiming error in the indoor UWB environment. The final experimental results showed that the optimized algorithm significantly reduced noise interference as well as improved positioning accuracy in an NLOS indoor environment with less than 10 cm positioning error.

17.
Dalton Trans ; 51(7): 2855-2862, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35098956

RESUMEN

In cases involving high levels of sulfur loading or high levels of current discharge, constructing sulfur composite cathodes via traditional coating preparation processes is an unsuitable way to overcome intractable problems relating to cathodes for use in lithium-sulfur batteries, such as poor conductivity, severe volume expansion, and the detrimental shuttle effect. Herein, a novel three-dimensional self-supported TiO2@C membrane with hierarchical interlinked porosity and oxygen vacancies was prepared via a phase-inversion method to act as a sulfur host. The procured TiO2-x@C membrane facilitates the infiltration of electrolyte, provides fast lithium-ion and electron transport channels and abundant sulfur loading sites, and shows superb structural buffering against the large volume changes during the conversion process between sulfur and lithium sulfide. More importantly, the introduction of oxygen vacancies not only enhances the conductivity of the original TiO2, but it also improves the corresponding adsorption abilities toward polysulfides and the subsequent transformation dynamics. Therefore, the TiO2-x@C membrane can significantly inhibit the polysulfide shuttle effect through polar chemisorption and conversion catalysis. Based on the above superiorities, the TiO2-x@C/S membrane electrode exhibits an impressive lifespan of more than 500 cycles at 2 C with a prominent ultimate specific discharge capacity of 715.2 mA h g-1.

18.
J Speech Lang Hear Res ; 64(12): 4664-4681, 2021 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-34705567

RESUMEN

PURPOSE: It has been reported that tone language-speaking children with autism demonstrate speech-specific lexical tone processing difficulty, although they have intact or even better-than-normal processing of nonspeech/melodic pitch analogues. In this early efficacy study, we evaluated the therapeutic potential of Auditory-Motor Mapping Training (AMMT) in facilitating speech and word output for Mandarin-speaking nonverbal and low-verbal children with autism, in comparison with a matched non-AMMT-based control treatment. METHOD: Fifteen Mandarin-speaking nonverbal and low-verbal children with autism spectrum disorder participated and completed all the AMMT-based treatment sessions by intoning (singing) and tapping the target words delivered via an app, whereas another 15 participants received control treatment. Generalized linear mixed-effects models were created to evaluate speech production accuracy and word production intelligibility across different groups and conditions. RESULTS: Results showed that the AMMT-based treatment provided a more effective training approach in accelerating the rate of speech (especially lexical tone) and word learning in the trained items. More importantly, the enhanced training efficacy on lexical tone acquisition remained at 2 weeks after therapy and generalized to untrained tones that were not practiced. Furthermore, the low-verbal participants showed higher improvement compared to the nonverbal participants. CONCLUSIONS: These data provide the first empirical evidence for adopting the AMMT-based training to facilitate speech and word learning in Mandarin-speaking nonverbal and low-verbal children with autism. This early efficacy study holds promise for improving lexical tone production in Mandarin-speaking children with autism but should be further replicated in larger scale randomized studies. Supplemental Material https://doi.org/10.23641/asha.16834627.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Percepción del Habla , Trastorno del Espectro Autista/terapia , Trastorno Autístico/terapia , Niño , Humanos , Lenguaje , Habla
19.
J Perioper Pract ; 31(3): 80-88, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32301383

RESUMEN

BACKGROUND: Perioperative stroke-related mortality in the non-cardiovascular, non-neurological surgery population is an uncommon, yet devastating outcome. A combination of emboli and hypoperfusion may cause large vessel occlusions leading to perioperative strokes and mortality. Identifying independent risk factors for perioperative stroke-related mortality may enhance risk-stratification algorithms and preventative therapies. OBJECTIVES: This study utilised cause-of-death data to determine independent risk scores for common surgical comorbidities that may lead to perioperative stroke-related mortality, including atrial fibrillation and asymptomatic carotid stenosis. METHODS: This retrospective, IRB-exempt, case-control study evaluated non-cardiovascular, non-neurological surgical patients in a claims-based database. ICD-10-CM and ICD-9-CM codes identified cause of death and comorbidity incidences, respectively. A multivariate regression analysis then established adjusted independent risk scores of each comorbidity in relation to perioperative stroke-related mortality. RESULTS: Patients with atrial fibrillation were more likely (1.7 aOR, 95% CI (1.1, 2.8) p = 0.02) to die from perioperative stroke-related mortality than from other causes. No association was found with asymptomatic carotid stenosis. Further, in-hospital strokes (25.9 aOR, 95% CI (16.0, 41.8) p < 0.001) or diabetes (1.8 aOR, 95% CI (1.1, 2.9) p = 0.02) may increase perioperative stroke-related mortality risk. CONCLUSIONS: Atrial fibrillation, diabetes and in-hospital strokes may be independent risk factors for perioperative stroke-related mortality in the non-cardiovascular, non-neurological surgery population.


Asunto(s)
Accidente Cerebrovascular , Estudios de Casos y Controles , Comorbilidad , Mortalidad Hospitalaria , Humanos , Estudios Retrospectivos , Factores de Riesgo , Accidente Cerebrovascular/epidemiología
20.
United European Gastroenterol J ; 9(2): 139-149, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33871926

RESUMEN

BACKGROUND: Persistent organ failure (POF) is the strongest determinant of mortality in acute pancreatitis (AP). There is a paucity of data regarding the impact of different POF attributes on mortality and the role of different characteristics of systemic inflammatory response syndrome (SIRS) in the risk of developing POF. OBJECTIVE: We aimed to assess the association of POF dynamic features with mortality and SIRS characteristics with POF. METHODS: We studied 1544 AP subjects prospectively enrolled at 22 international centers (APPRENTICE consortium). First, we estimated the association of onset, duration, and maximal score of SIRS with POF. Then, we evaluated the risk of mortality based on POF onset, duration, number, type, and sequence of organs affected. Analyses were adjusted for potential confounders. RESULTS: 58% had SIRS, 11% developed POF, and 2.5% died. Early SIRS, persistent SIRS, and maximal SIRS score ≥ 3 were independently associated with higher risk of POF (p < 0.05). Mortality risk in POF was higher with two (33%, odds ratio [OR] = 10.8, 3.3-34.9) and three (48%, OR = 20.2, 5.9-68.6) organs failing, in comparison to single POF (4%). In subjects with multiple POF, mortality was higher when the cardiovascular and respiratory systems failed first or concurrently as compared to when the renal system failed first or concurrently with other organ (p < 0.05). In multivariate regression model, the number and sequence of organs affected in POF were associated with mortality (p < 0.05). Onset and duration of POF had no impact mortality. CONCLUSION: In AP patients with POF, the risk of mortality is influenced by the number, type, and sequence of organs affected. These results are useful for future revisions of AP severity classification systems.


Asunto(s)
Insuficiencia Multiorgánica/complicaciones , Insuficiencia Multiorgánica/mortalidad , Pancreatitis/complicaciones , Pancreatitis/mortalidad , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Síndrome de Respuesta Inflamatoria Sistémica/etiología
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