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1.
Nature ; 600(7887): 75-80, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34853455

RESUMEN

Nonlinear wave-matter interactions may give rise to solitons, phenomena that feature inherent stability in wave propagation and unusual spectral characteristics. Solitons have been created in a variety of physical systems and have had important roles in a broad range of applications, including communications, spectroscopy and metrology1-4. In recent years, the realization of dissipative Kerr optical solitons in microcavities has led to the generation of frequency combs in a chip-scale platform5-10. Within a cavity, photons can interact with mechanical modes. Cavity optomechanics has found applications for frequency conversion, such as microwave-to-optical or radio-frequency-to-optical11-13, of interest for communications and interfacing quantum systems operating at different frequencies. Here we report the observation of mechanical micro-solitons excited by optical fields in an optomechanical microresonator, expanding soliton generation in optical resonators to a different spectral window. The optical field circulating along the circumference of a whispering gallery mode resonator triggers a mechanical nonlinearity through optomechanical coupling, which in turn induces a time-varying periodic modulation on the propagating mechanical mode, leading to a tailored modal dispersion. Stable localized mechanical wave packets-mechanical solitons-can be realized when the mechanical loss is compensated by phonon gain and the optomechanical nonlinearity is balanced by the tailored modal dispersion. The realization of mechanical micro-solitons driven by light opens up new avenues for optomechanical technologies14 and may find applications in acoustic sensing, information processing, energy storage, communications and surface acoustic wave technology.

2.
J Neurosci ; 44(20)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38565291

RESUMEN

Microglia undergo two-stage activation in neurodegenerative diseases, known as disease-associated microglia (DAM). TREM2 mediates the DAM2 stage transition, but what regulates the first DAM1 stage transition is unknown. We report that glucose dyshomeostasis inhibits DAM1 activation and PKM2 plays a role. As in tumors, PKM2 was aberrantly elevated in both male and female human AD brains, but unlike in tumors, it is expressed as active tetramers, as well as among TREM2+ microglia surrounding plaques in 5XFAD male and female mice. snRNAseq analyses of microglia without Pkm2 in 5XFAD mice revealed significant increases in DAM1 markers in a distinct metabolic cluster, which is enriched in genes for glucose metabolism, DAM1, and AD risk. 5XFAD mice incidentally exhibited a significant reduction in amyloid pathology without microglial Pkm2 Surprisingly, microglia in 5XFAD without Pkm2 exhibited increases in glycolysis and spare respiratory capacity, which correlated with restoration of mitochondrial cristae alterations. In addition, in situ spatial metabolomics of plaque-bearing microglia revealed an increase in respiratory activity. These results together suggest that it is not only glycolytic but also respiratory inputs that are critical to the development of DAM signatures in 5XFAD mice.


Asunto(s)
Glucosa , Homeostasis , Ratones Transgénicos , Microglía , Animales , Microglía/metabolismo , Microglía/patología , Ratones , Homeostasis/fisiología , Glucosa/metabolismo , Masculino , Femenino , Humanos , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/genética , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Receptores Inmunológicos/metabolismo , Receptores Inmunológicos/genética , Glucólisis/fisiología , Proteínas de Unión a Hormona Tiroide
3.
Circulation ; 148(8): 651-660, 2023 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-37603600

RESUMEN

BACKGROUND: People with type 2 diabetes and albuminuria are at an elevated risk for cardiac and renal events. The optimal biomarkers to aid disease prediction and to understand the benefits of sodium-glucose cotransporter-2 inhibition remain unclear. METHODS: Among 2627 study participants in the CREDENCE trial (Canagliflozin and Renal Events in Diabetes With Established Nephropathy Clinical Evaluation), concentrations of NT-proBNP (N-terminal pro-B-type natriuretic peptide), high-sensitivity cardiac troponin T, growth differentiation factor-15, and IGFBP7 (insulin-like growth factor binding protein 7) were measured. The effect of canagliflozin on biomarker concentrations was evaluated. The prognostic potential of each biomarker on the primary outcome (a composite of end-stage kidney disease [dialysis, transplantation, or a sustained estimated glomerular filtration rate of <15 mL·min-1·1.73 m-2], doubling of the serum creatinine level, or renal death or cardiovascular death) was assessed. RESULTS: The median (quartiles 1 and 3) concentration of each biomarker was generally elevated: NT-proBNP, 180 ng/L (82, 442 ng/L); high-sensitivity cardiac troponin T, 19 ng/L (12, 29 ng/L); growth differentiation factor-15, 2595 ng/L (1852, 3775 ng/L); and IGFBP7, 121.8 ng/mL (105.4, 141.5 ng/mL). At 1 year, the biomarkers all rose by 6% to 29% in the placebo arm but only by 3% to 10% in the canagliflozin arm (all P<0.01 in multivariable linear mixed-effect models). Baseline concentrations of each biomarker were strongly predictive of cardiac and renal outcomes. When the biomarkers were analyzed together in a multimarker panel, individuals with high risk scores (hazard ratio [HR], 4.01 [95% CI, 2.52-6.35]) and moderate risk scores (HR, 2.39 [95% CI, 1.48-3.87]) showed a higher risk for the primary outcome compared with those with low risk scores. By 1 year, a 50% increase in NT-proBNP (HR, 1.11 [95% CI, 1.08-1.15]), high-sensitivity cardiac troponin T (HR, 1.86 [95% CI, 1.64-2.10]), growth differentiation factor-15 (HR, 1.45 [95% CI, 1.24-1.70]), and IGFBP7 (HR, 3.76 [95% CI, 2.54-5.56]) was associated with risk of the primary outcome. CONCLUSIONS: Multiple cardiorenal stress biomarkers are strongly prognostic in people with type 2 diabetes and albuminuria. Canagliflozin modestly reduced the longitudinal trajectory of rise in each biomarker. Change in the biomarker level in addition to the baseline level augments the primary outcome prediction. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02065791.


Asunto(s)
Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Humanos , Nefropatías Diabéticas/diagnóstico , Nefropatías Diabéticas/tratamiento farmacológico , Canagliflozina/uso terapéutico , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Albuminuria , Troponina T , Biomarcadores , Factores de Diferenciación de Crecimiento
4.
Neuroimage ; 293: 120632, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38701994

RESUMEN

During aging, the brain is subject to greater oxidative stress (OS), which is thought to play a critical role in cognitive impairment. Glutathione (GSH), as a major antioxidant in the brain, can be used to combat OS. However, how brain GSH levels vary with age and their associations with cognitive function is unclear. In this study, we combined point-resolved spectroscopy and edited spectroscopy sequences to investigate extended and closed forms GSH levels in the anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and occipital cortex (OC) of 276 healthy participants (extended form, 166 females, age range 20-70 years) and 15 healthy participants (closed form, 7 females, age range 26-56 years), and examined their relationships with age and cognitive function. The results revealed decreased extended form GSH levels with age in the PCC among 276 participants. Notably, the timecourse of extended form GSH level changes in the PCC and ACC differed between males and females. Additionally, positive correlations were observed between extended form GSH levels in the PCC and OC and visuospatial memory. Additionally, a decreased trend of closed form GSH levels with age was also observed in the PCC among 15 participants. Taken together, these findings enhance our understanding of the brain both closed and extended form GSH time course during normal aging and associations with sex and memory, which is an essential first step for understanding the neurochemical underpinnings of healthy aging.


Asunto(s)
Envejecimiento , Glutatión , Humanos , Femenino , Persona de Mediana Edad , Masculino , Adulto , Anciano , Glutatión/metabolismo , Envejecimiento/metabolismo , Envejecimiento/fisiología , Adulto Joven , Memoria Espacial/fisiología , Lóbulo Occipital/metabolismo , Giro del Cíngulo/metabolismo , Encéfalo/metabolismo
5.
Am Heart J ; 271: 38-47, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38401646

RESUMEN

BACKGROUND: Circulating concentrations of vascular endothelial growth factor (VEGF) family members may be abnormally elevated in type 2 diabetes (T2D). The roles of placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFLT-1), and VEGF-A in cardio-renal complications of T2D are not established. METHOD: The 2602 individuals with diabetic kidney disease (DKD) from the Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation trial were randomized to receive canagliflozin or placebo and followed for incident cardio-renal outcomes. PlGF, sFLT-1, and VEGF-A were measured at baseline, year 1, and year 3. Primary outcome was a composite of end-stage kidney disease, doubling of the serum creatinine, or renal/cardiovascular death. Cox proportional hazard regression was used to investigate the association between biomarkers with adverse clinical events. RESULTS: At baseline, individuals with higher PlGF levels had more prevalent cardiovascular disease compared to those with lower values. Treatment with canagliflozin did not meaningfully change PlGF, sFLT-1, and VEGF-A concentrations at years 1 and 3. In a multivariable model, 1 unit increases in baseline log PlGF (hazard ratio [HR]: 1.76, 95% confidence interval [CI]: 1.23, 2.54, P-value = .002), sFLT-1 (HR: 3.34, [95% CI: 1.71, 6.52], P-value < .001), and PlGF/sFLT-1 ratio (HR: 4.83, [95% CI: 0.86, 27.01], P-value = .07) were associated with primary composite outcome, while 1 unit increase in log VEGF-A did not increase the risk of primary outcome (HR: 0.96 [95% CI: 0.81, 1.07]). Change by 1 year of each biomarker was also assessed: HR (95% CI) of primary composite outcome was 2.45 (1.70, 3.54) for 1 unit increase in 1-year concentration of log PlGF, 4.19 (2.18, 8.03) for 1 unit increase in 1-year concentration of log sFLT-1, and 21.08 (3.79, 117.4) for 1 unit increase in 1-year concentration of log PlGF/sFLT-1. Increase in 1-year concentrations of log VEGF-A was not associated with primary composite outcome (HR: 1.08, [95% CI: 0.93, 1.24], P-value = .30). CONCLUSIONS: People with T2D and DKD with elevated levels of PlGF, sFLT-1, and PlGF/sFLT-1 ratio were at a higher risk for cardiorenal events. Canagliflozin did not meaningfully decrease concentrations of PlGF, sFLT-1, and VEGF-A. CLINICAL TRIAL: CREDENCE, https://clinicaltrials.gov/ct2/show/NCT02065791.


Asunto(s)
Biomarcadores , Canagliflozina , Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Factor de Crecimiento Placentario , Factor A de Crecimiento Endotelial Vascular , Receptor 1 de Factores de Crecimiento Endotelial Vascular , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Biomarcadores/sangre , Canagliflozina/uso terapéutico , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/epidemiología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/sangre , Nefropatías Diabéticas/sangre , Nefropatías Diabéticas/epidemiología , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/sangre , Factor de Crecimiento Placentario/sangre , Factores de Riesgo , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Factor A de Crecimiento Endotelial Vascular/sangre , Receptor 1 de Factores de Crecimiento Endotelial Vascular/sangre
6.
J Card Fail ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38614444

RESUMEN

BACKGROUND: The prognosis of individuals with and without an established heart failure (HF) diagnosis and similarly elevated N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels is not well-known. METHODS AND RESULTS: CANVAS (Canagliflozin Cardiovascular Assessment Study) trial participants were stratified according to baseline NT-proBNP quartiles and history of HF at baseline. Adjusted event rates per 1000 patient-years of follow-up for hospitalizations for HF, cardiovascular mortality, and kidney events were assessed, and hazard ratios (HR) were calculated using Cox proportional hazard models. Of the 3507 participants with available NT-proBNP concentrations, 471 (13.4%) had history of HF. The incidence rate per 1000 patient-years for hospitalizations for HF increased across the NT-proBNP quartiles in patients with (0, 2.8, 13.4, and 40.1; P < .001) and without (1.8, 3.1, 6.0, and 19.1; P < .001) HF, with a significantly higher risk in patients with HF compared with those without (with HF, quartile 3 HR 9.28 [interquartile range (IQR) 1.15-75.05]; P = .04; without HF, quartile 4 HR 4.86 [95% CI, 2.08-11.35]; P < .001). A similar higher risk for kidney events was seen in HF patients (with HF, quartile 4 HR 6.94 [95% CI, 2.66-18.08]; P = .001; without HF, quartile 4 HR 4.85 [95% CI, 3.02-7.80]; P = .001). Similar trends were seen for cardiovascular mortality. CONCLUSIONS: Among patients with type 2 diabetes and cardiovascular risk, an elevated NT-proBNP level was associated with worse HF and kidney outcomes in general, regardless of history of HF; however, the presence of a clinical diagnosis of HF at baseline was associated with an incrementally higher risk, particularly in higher NT-proBNP quartiles.

7.
Opt Express ; 32(1): 179-187, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38175047

RESUMEN

The Tavis-Cummings model is intensively investigated in quantum optics and has important applications in generation of multi-atom entanglement. Here, we employ a superconducting circuit quantum electrodynamic system to study a modified Tavis-Cummings model with directly-coupled atoms. In our device, three superconducting artificial atoms are arranged in a chain with direct coupling through fixed capacitors and strongly coupled to a transmission line resonator. By performing transmission spectrum measurements, we observe different anticrossing structures when one or two qubits are resonantly coupled to the resonator. In the case of the two-qubit Tavis-Cummings model without qubit-qubit interaction, we observe two dips at the resonance point of the anticrossing. The splitting of these dips is determined by Δ λ=2g12+g32, where g1 and g3 are the coupling strengths between Qubit 1 and the resonator, and Qubit 3 and the resonator, respectively. The direct coupling J12 between the two qubits results in three dressed states in the two-qubit Tavis-Cummings model at the frequency resonance point, leading to three dips in the transmission spectrum. In this case, the distance between the two farthest and asymmetrical dips, arising from the energy level splitting, is larger than in the previous case. The frequency interval between these two dips is determined by the difference in eigenvalues (Δ λ=ε 1+-ε 1-), obtained through numerical calculations. What we believe as novel and intriguing experimental results may potentially advance quantum optics experiments, providing valuable insights for future research.

8.
Cardiovasc Diabetol ; 23(1): 49, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302936

RESUMEN

BACKGROUND: Diabetic cardiomyopathy (DbCM) is a form of Stage B heart failure (HF) at high risk for progression to overt disease. Using baseline characteristics of study participants from the Aldose Reductase Inhibition for Stabilization of Exercise Capacity in Heart Failure (ARISE-HF) Trial we sought to characterize clinical characteristics of individuals with findings consistent with DbCM. METHODS: Among study participants meeting inclusion criteria, clinical characteristics, laboratory testing, imaging, Kansas City Cardiomyopathy Questionnaire (KCCQ), Physical Activity Scale of the Elderly (PASE) and cardiopulmonary exercise testing (CPET) results were tabulated. Cluster phenogroups were identified. RESULTS: Among 691 study participants (mean age 67.4 years; 50% were female), mean duration of type 2 diabetes mellitus (T2DM) was 14.5 years. The median (Q1, Q3) N-terminal pro-B type natriuretic peptide and high sensitivity cardiac troponin T were 71 (35, 135) ng/L and 9 [6, 12] ng/L. The most common echocardiographic abnormalities were reduced global longitudinal strain in 25.3% and impaired diastolic relaxation in 17.7%. Despite rather well-preserved KCCQ scores the average PASE score was markedly impaired at 155 accompanied by an average maximal oxygen consumption of 15.7 mL/Kg/minute on CPET. In K-means clustering, 4 phenogroups were identified including a higher-risk group with more advanced age, greater elevation of cardiac biomarkers, and more prevalent evidence for diastolic dysfunction and left ventricular hypertrophy. CONCLUSIONS: Baseline data from the ARISE-HF Trial provide clinical characterization of individuals with T2DM and features of stage B HF, and may help clarify the diagnosis of DbCM. TRIAL REGISTRATION: ARISE-HF, NCT04083339.


Asunto(s)
Diabetes Mellitus Tipo 2 , Cardiomiopatías Diabéticas , Insuficiencia Cardíaca , Humanos , Femenino , Anciano , Masculino , Cardiomiopatías Diabéticas/diagnóstico por imagen , Cardiomiopatías Diabéticas/etiología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Volumen Sistólico , Insuficiencia Cardíaca/diagnóstico , Hipertrofia Ventricular Izquierda , Función Ventricular Izquierda
9.
Exp Cell Res ; 424(1): 113473, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36634743

RESUMEN

Long non-coding RNA (lncRNA) anomalies cause early ovarian failure. LncRNA nuclear enriched abundant transcript 1 (NEAT1) was down-regulated in premature ovarian failure (POF) mice and connected to the illness, however, the mechanism remained unclear. The levels of gene and protein were measured by using quantitative real-time polymerase chain reaction, Western blot, and immunofluorescence. Follicle stimulating hormone (FSH), estradiol (E2), and luteinizing hormone (LH) levels were determined using enzyme-linked immunosorbent assay (ELISA). 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and flow cytometry were used to determine cell viability and apoptosis. The interaction of NEAT1, miR-654, and stanniocalcin-2 (STC2) was verified by dual-luciferase reporter assay or RNA binding protein immunoprecipitation (RIP) assays. The results showed NEAT1 and STC2 down-regulated, while miR-654 up-regulated in POF mice. Overexpression of NEAT1 reduced apoptosis and autophagy in cyclophosphamide (CTX)-treated ovarian granulosa cells (OGCs), and Bax, cleaved-caspase3, LC3B, LC3II/LC3I ratio were decreased and Bcl-2 and p62 were raised. NEAT1 suppressed miR-654 expression by directly targeting miR-654. The inhibition of NEAT1 overexpression on apoptosis and autophagy in OGCs was reversed by miR-654 mimics. STC2 was a target gene of miR-654, and miR-654 inhibitor reduced the apoptosis and autophagy by regulating the STC2/MAPK axis. To sum up, NEAT1 reduced miR-654 expression and modulated the STC2/MAPK pathway to decrease apoptosis and autophagy in POF, indicating a potential therapeutic target.


Asunto(s)
Apoptosis , Autofagia , Células de la Granulosa , MicroARNs , ARN Largo no Codificante , Animales , Ratones , Apoptosis/genética , Autofagia/genética , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Transducción de Señal , Células de la Granulosa/metabolismo , Células de la Granulosa/patología
10.
BMC Public Health ; 24(1): 723, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448849

RESUMEN

BACKGROUND: Deep learning (DL), a specialized form of machine learning (ML), is valuable for forecasting survival in various diseases. Its clinical applicability in real-world patients with gastric cancer (GC) has yet to be extensively validated. METHODS: A combined cohort of 11,414 GC patients from the Surveillance, Epidemiology and End Results (SEER) database and 2,846 patients from a Chinese dataset were utilized. The internal validation of different algorithms, including DL model, traditional ML models, and American Joint Committee on Cancer (AJCC) stage model, was conducted by training and testing sets on the SEER database, followed by external validation on the Chinese dataset. The performance of the algorithms was assessed using the area under the receiver operating characteristic curve, decision curve, and calibration curve. RESULTS: DL model demonstrated superior performance in terms of the area under the curve (AUC) at 1, 3, and, 5 years post-surgery across both datasets, surpassing other ML models and AJCC stage model, with AUCs of 0.77, 0.80, and 0.82 in the SEER dataset and 0.77, 0.76, and 0.75 in the Chinese dataset, respectively. Furthermore, decision curve analysis revealed that the DL model yielded greater net gains at 3 years than other ML models and AJCC stage model, and calibration plots at 3 years indicated a favorable level of consistency between the ML and actual observations during external validation. CONCLUSIONS: DL-based model was established to accurately predict the survival rate of postoperative patients with GC.


Asunto(s)
Aprendizaje Profundo , Neoplasias Gástricas , Humanos , Algoritmos , Área Bajo la Curva , Pueblo Asiatico , Neoplasias Gástricas/cirugía , Pueblos de América del Norte
11.
Ann Gen Psychiatry ; 23(1): 19, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730281

RESUMEN

BACKGROUND: Anxiety disorders can cause serious physical and psychological damage, so many anxiety scales have been developed internationally to measure anxiety disorders, but due to the cultural differences and cultural dependence of quality of life between Chinese and Western cultures, it is difficult to reflect the main characteristics of Chinese patients. Therefore, we developed a scale suitable for Chinese patients with anxiety disorders: the Anxiety Disorders Scale of the Quality of Life Instruments for Chronic Diseases (QLICD-AD), hoping to achieve satisfactory QOL assessments for anxiety disorders. OBJECTIVES: Items from the Anxiety Disorders Scale of the Quality of Life in Chronic Disease Instrument QLICD-AD system were analyzed using CTT and IRT to lay the groundwork for further refinement of the scale to accurately measure anxiety disorders. METHODS: 120 patients with anxiety disorder were assessed using the QLICD-AD (V2.0). Descriptive statistics, variability method, correlation coefficient method, factor analysis and Cronbach's coefficient of CTT, and graded response model (GRM) of item response theory were used to analyze the items of the scale. RESULT: CTT analysis showed that the standard deviation of each item was between 0.928 and 1.466; Pearson correlation coefficients of item-to-domain were generally greater than 0.5 and also greater than that of item-to-other domain; the Cronbach 's of the total scale was 0.931, α of each domain was between 0.706 and 0.865. IRT analysis showed that the discrimination was between 1.14 and 1.44. The difficulty parameter of all items increased with the increase of grade. But some items (GPH6,GPH8,GPS3,GSO2-GSO4,AD2,AD5) difficulty parameters were less than 4 or greater than 4. The average of information amount was between 0.022 and 0.910. CONCLUSION: Based on CTT and IRT analysis, most items of the QLICD-AD (V2.0) scale have good performance and good differentiation, but a few items still need further revision. Suggests that the QLICD-AD (V2.0) appears to be a valid measure of anxiety disorders. It may effectively improve the diagnosticity of anxiety disorders, but due to the limitations of the current sample, further validation is needed in a broader population extrapolation trial.

12.
Nano Lett ; 23(14): 6651-6657, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37459201

RESUMEN

Thermodynamic metastable water in negative pressure provides a possible solution to elevate the upper limit of evaporative heat transfer capacity and the efficiency of low-grade heat utilization, but practical implementations are challenging due to the difficulty in generating and maintaining large negative pressure. Herein, we report a novel structure with a hydrogel film as the evaporation surface and a permeable substrate as the functional layer to suppress cavitation. Based on the structure, we achieve an evaporation-driven flow system with negative pressure as low as -1.67 MPa. Molecular dynamics simulations elucidate the importance of strong water-polymer interactions in negative pressure generation. With the large negative pressure, we demonstrate a streaming potential generator that spontaneously converts environmental energy into electricity and outputs a voltage of 1.06 V. Moreover, we propose a "negative pressure heat pipe", which achieves a high heat transfer density of 9.6 kW cm-2 with a flow length of 1 m.

13.
J Environ Manage ; 354: 120329, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38373375

RESUMEN

Microplastics (MPs) usually appear in the aquatic environment as complex pollutants in combination with other environmental pollutants, such as levofloxacin (LVFX). After a 45-day exposure to LVFX and MPs with different particle sizes at environmental levels, LVFX was neurotoxic to Rana nigromaculata tadpoles. The order of the effects of the exposure treatment on tadpole behavior was: LVFX-MP3>LVFX-MP1>LVFX-MP2 ≥ LVFX. Results of transcriptome analysis of tadpole brain tissue showed that LVFX in combination with 0.10 and 10.00 µm MP interferes with the nervous system through the cell adhesion molecules pathway. Interestingly, the order of effects of the co-exposure on oxidative stress in the intestine was inconsistent with that of tadpole behavior. We found that Paraacteroides might be a microplastic indicator species for the gut microbiota of aquatic organisms. The results of the targeted metabolism of neurotransmitters in the intestine suggest that in the LVFX-MP2 treatment, LVFX alleviated the intestinal microbiota disorder caused by 1.00 µm MP, by regulating intestinal microbiota participating in the TCA cycle VI and gluconeogenesis and tetrapyrrole biosynthesis I, while downregulating Met and Orn, and upregulating 5HIAA, thereby easing the neurotoxicity to tadpoles exposed to LVFX-MP2. This work is of great significance for the comprehensive assessment of the aquatic ecological risks of microplastics-antibiotic compound pollutants.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Animales , Levofloxacino/análisis , Microplásticos/toxicidad , Plásticos , Tamaño de la Partícula , Intestinos/química , Encéfalo , Ranidae , Contaminantes Ambientales/análisis , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis
14.
J Environ Sci (China) ; 138: 153-166, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38135384

RESUMEN

The PdPtVOx/CeO2-ZrO2 (PdPtVOx/CZO) catalysts were obtained by using different approaches, and their physical and chemical properties were determined by various techniques. Catalytic activities of these materials in the presence of H2O or SO2 were evaluated for the oxidation of ethylbenzene (EB). The PdPtVOx/CZO sample exhibited high catalytic activity, good hydrothermal stability, and reversible sulfur dioxide-poisoning performance, over which the specific reaction rate at 160°C, turnover frequency at 160°C (TOFPd or Pt), and apparent activation energy were 72.6 mmol/(gPt⋅sec) or 124.2 mmol/(gPd⋅sec), 14.2 sec-1 (TOFPt) or 13.1 sec-1 (TOFPd), and 58 kJ/mol, respectively. The large EB adsorption capacity, good reducibility, and strong acidity contributed to the good catalytic performance of PdPtVOx/CZO. Catalytic activity of PdPtVOx/CZO decreased when 50 ppm SO2 or (1.0 vol.% H2O + 50 ppm SO2) was added to the feedstock, but was gradually restored to its initial level after the SO2 was cut off. The good reversible sulfur dioxide-resistant performance of PdPtVOx/CZO was associated with the facts: (i) the introduction of SO2 leads to an increase in surface acidity; (ii) V can adsorb and activate SO2, thus accelerating formation of the SOx2- (x = 3 or 4) species at the V and CZO sites, weakening the adsorption of sulfur species at the PdPt active sites, and hence protecting the PdPt active sites to be not poisoned by SO2. EB oxidation over PdPtVOx/CZO might take place via the route of EB â†’ styrene â†’ phenyl methyl ketone â†’ benzaldehyde â†’ benzoic acid â†’ maleic anhydride â†’ CO2 and H2O.


Asunto(s)
Derivados del Benceno , Dióxido de Azufre , Dióxido de Azufre/química , Oxidación-Reducción , Catálisis , Estrés Oxidativo , Amoníaco/química
15.
Carcinogenesis ; 44(3): 242-251, 2023 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-36999754

RESUMEN

Overactive fatty acid metabolism is usually found in hematological malignancies including multiple myeloma (MM), but the underlying mechanisms remain unclear. Here, we reveal that acyl-CoA synthetase long-chain family member 4 (ACSL4) is abnormally overexpressed in MM cell lines and MM patients compared to healthy donors. Knockdown of ACSL4 inhibited MM cell proliferation and reduced fatty acid levels possibly by regulating lipid metabolism genes including c-Myc and sterol regulatory element binding proteins (SREBPs). As a propellent in ferroptosis, ACSL4 also determines the sensitivity of MM cells to ferroptosis inducer RSL3. Knockdown of ACSL4 rendered MM cells resistance to ferroptosis. Our findings suggest that ACSL4 is a double-edged sword target in MM. Based on the high expression of ACSL4, ferroptosis induction represents a promising therapeutic strategy for MM.


Asunto(s)
Coenzima A Ligasas , Ferroptosis , Mieloma Múltiple , Humanos , Línea Celular Tumoral , Proliferación Celular , Coenzima A Ligasas/genética , Coenzima A Ligasas/metabolismo , Ácidos Grasos , Ferroptosis/genética , Mieloma Múltiple/genética
16.
J Am Chem Soc ; 145(20): 11110-11120, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37191364

RESUMEN

Improving the product selectivity meanwhile restraining deep oxidation still remains a great challenge over the supported Pd-based catalysts. Herein, we demonstrate a universal strategy where the surface strong oxidative Pd sites are partially covered by the transition metal (e. g., Cu, Co, Ni, and Mn) oxide through thermal treatment of alloys. It could effectively inhibit the deep oxidation of isopropanol and achieve the ultrahigh selectivity (>98%) to the target product acetone in a wide temperature range of 50-200 °C, even at 150-200 °C with almost 100% isopropanol conversion over PdCu1.2/Al2O3, while an obvious decline in acetone selectivity is observed from 150 °C over Pd/Al2O3. Furthermore, it greatly improves the low-temperature catalytic activity (acetone formation rate at 110 °C over PdCu1.2/Al2O3, 34.1 times higher than that over Pd/Al2O3). The decrease of surface Pd site exposure weakens the cleavage for the C-C bond, while the introduction of proper CuO shifts the d-band center (εd) of Pd upward and strengthens the adsorption and activation of reactants, providing more reactive oxygen species, especially the key super oxygen species (O2-) for selective oxidation, and significantly reducing the barrier of O-H and ß-C-H bond scission. The molecular-level understanding of the C-H and C-C bond scission mechanism will guide the regulation of strong oxidative noble metal sites with relatively inert metal oxide for the other selective catalytic oxidation reactions.

17.
J Am Chem Soc ; 145(29): 15869-15878, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37449950

RESUMEN

Designing new synthesis routes to fabricate highly thermally durable precious metal single-atom catalysts (SACs) is challenging in industrial applications. Herein, a general strategy is presented that starts from dual-metal nanocrystals (NCs), using bimetallic NCs as a facilitator to spontaneously convert a series of noble metals to single atoms on aluminum oxide. The metal single atoms are captured by cation defects in situ formed on the surface of the inverse spinel (AB2O4) structure, which process provides numerous anchoring sites, thus facilitating generation of the isolated metal atoms that contributes to the extraordinary thermodynamic stability. The Pd1/AlCo2O4-Al2O3 shows not only improved low-temperature activity but also unprecedented (hydro)thermal stability for CO and propane oxidation under harsh aging conditions. Furthermore, our strategy exhibits a small scaling-up effect by the simple physical mixing of commercial metal oxide aggregates with Al2O3. The good regeneration between oxidative and reductive atmospheres of these ionic palladium species makes this catalyst system of potential interest for emissions control.

18.
Genet Med ; 25(7): 100837, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37057674

RESUMEN

PURPOSE: The aim of this study was to describe the clinical impact of commercial laboratories issuing conflicting classifications of genetic variants. METHODS: Results from 2000 patients undergoing a multigene hereditary cancer panel by a single laboratory were analyzed. Clinically significant discrepancies between the laboratory-provided test reports and other major commercial laboratories were identified, including differences between pathogenic/likely pathogenic and variant of uncertain significance (VUS) classifications, via review of ClinVar archives. For patients carrying a VUS, clinical documentation was assessed for evidence of provider awareness of the conflict. RESULTS: Fifty of 975 (5.1%) patients with non-negative results carried a variant with a clinically significant conflict, 19 with a pathogenic/likely pathogenic variant reported in APC or MUTYH, and 31 with a VUS reported in CDKN2A, CHEK2, MLH1, MSH2, MUTYH, RAD51C, or TP53. Only 10 of 28 (36%) patients with a VUS with a clinically significant conflict had a documented discussion by a provider about the conflict. Discrepant counseling strategies were used for different patients with the same variant. Among patients with a CDKN2A variant or a monoallelic MUTYH variant, providers were significantly more likely to make recommendations based on the laboratory-reported classification. CONCLUSION: Our findings highlight the frequency of variant interpretation discrepancies and importance of clinician awareness. Guidance is needed on managing patients with discrepant variants to support accurate risk assessment.


Asunto(s)
Variación Genética , Neoplasias , Humanos , Neoplasias/genética , Laboratorios , Pruebas Genéticas/métodos , Predisposición Genética a la Enfermedad
19.
J Card Fail ; 2023 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-37816446

RESUMEN

OBJECTIVES: To assess tissue Doppler-derived mitral annular isovolumic contraction velocity (ICV) after starting sacubitril/valsartan (sac/val) for the treatment of heart failure with reduced ejection fraction (HFrEF) and left ventricular [LV] EF < 40%). BACKGROUND: ICV may inform load-independent systolic function; combining ICV and LVEF may improve assessment of LV contractility. METHODS: Among 651 participants with HFrEF treated with sac/val, echocardiograms were performed at baseline, 6 and 12 months. Pretreatment median ICVs and LVEFs were used for classification to predict LV reverse remodeling, health status using the Kansas City Cardiomyopathy Questionnaire, and biomarker concentrations. RESULTS: The mean age was 64.6 ± 12.4 years, and 28% were women, baseline LVEF: 28.9% ± 6.9%. Compared to baseline, median ICV increased post sac/val therapy (4.6 [3.5, 6.1] vs 4.9 [3.6, 6.4]; P = 0.005). ICV added value to separate and combined models of biomarkers and clinical and echocardiographic variables for prediction of post-therapy EF recovery. Classification using baseline ICV/EF yielded relatively equal numbers in 4 groups based on low/high ICV or LVEF. Most deleterious results for remodeling, health status and biomarkers were found in patients with low ICV/low EF, whereas patients with high ICV/high EF had the best profiles; other groups were intermediate. Significant shifts toward better ICV/EF profiles were noted post sac/val treatment compared to baseline, with doubling of high ICV/high EF (241 [60%] vs 123 [31%]) and 78% reduction of low ICV/low EF (28 [7%] vs 125 [32%]). CONCLUSIONS: In HFrEF, ICV adds to the profiling of systolic function and represents an independent predictor of reverse cardiac remodeling after treatment with sac/val. ICV changes may be used for assessment of treatment responses.

20.
Opt Express ; 31(22): 36836-36844, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-38017825

RESUMEN

Order is one of the most important concepts to interpret various phenomena such as the emergence of turbulence and the life-evolution process. The generation of laser can also be treated as an ordering process in which the interaction between the laser beam and the gain medium leads to the correlation between photons in the output optical field. Here, we demonstrate experimentally in a hybrid Raman-laser-optomechanical system that an ordered Raman laser can be generated from an entropy-absorption process by a chaotic optomechanical resonator. When the optomechanical resonator is chaotic or disordered enough, the Raman-laser field is in an ordered lasing mode. This can be interpreted by the entropy transfer from the Raman-laser mode to the chaotic motion mediated by optomechanics. Different order parameters, such as the box-counting dimension, the maximal Lyapunov exponent, and the Kolmogorov entropy, are introduced to quantitatively analyze this entropy transfer process, by which we can observe the order transfer between the Raman-laser mode and the optomechanical resonator. Our study presents a new mechanism of laser generation and opens up new dimensions of research such as the modulation of laser by optomechanics.

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