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1.
ACS Sens ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39228132

RESUMEN

Intravital microscopy (IVM) is a valuable method for biomedical characterization of dynamic processes, which has been applied to many fields such as neuroscience, oncology, and immunology. During IVM, vibration suppression is a major challenge due to the inevitable respiration and heartbeat from live animals. In this study, taking liver IVM as an example, we have unraveled the vibration inhibition effect of liquid bridges by studying the friction characteristics of a moist surface on the mouse liver. We confirmed the presence of liquid bridges on the liver through fluorescence imaging, which can provide microscale and nondestructive liquid connections between adjacent surfaces. Liquid bridges were constructed to sufficiently stabilize the liver after abdominal dissection by covering it with a polymer film, taking advantage of the high adhesion properties of liquid bridges. We further prototyped a microscope-integrated vibration-damping device with adjustable film tension to simplify the sample preparation procedure, which remarkably decreased the liver vibration. In practical application scenarios, we observed the process of liposome phagocytosis by liver Kupffer cells with significantly improved image and video quality. Collectively, our method not only provided a feasible solution to vibration suppression in the field of IVM, but also has the potential to be applied to vibration damping of precision instruments or other fields that require nondestructive ″soft″ vibration damping.

2.
Nanoscale ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225006

RESUMEN

One-dimensional (1D) van der Waals (vdW) heterotubes, where different kinds of 1D nanotubes coaxially nest inside each other, offer a flexible platform for promising applications. The various properties of these 1D heterotubes depend on their diameter. Here, we present a systematic theoretical investigation into the structural and electronic properties of two kinds of 1D transition-metal dichalcogenide (TMD) heterotubes. We demonstrate that the thermodynamic stability of 1D heterotubes is determined by their interlayer distance. Additionally, we establish that the band alignment transition changes from type I to type II in 1D TMD heterotubes. We identify two distinct transition mechanisms, originating from the exchange of either the valence band maximum or the conduction band minimum. According to an electrostatic model, the band alignment transition is attributed to the interlayer electric field effect, which depends on the heterotube diameter. The findings in this work provide valuable physical insights into the band alignment transition in 1D heterotubes and are instrumental for their potential applications in nanotechnology.

3.
Prev Sci ; 25(6): 910-918, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39230657

RESUMEN

Tobacco retail outlet (TRO) density has been associated with increased cotinine levels in pregnant persons and their children. As such, the higher densities of TROs may represent higher levels of active smoking during pregnancy. The purpose of this study is to simulate the reduction in cotinine (a biomarker of smoke exposure) and health care utilization that could occur in pregnant persons under enactment of several candidate TRO reduction policy recommendations. Using existing retail outlet data from the state of North Carolina and from the Newborn Epigenetic Study (NEST), the present study created hypothetical policy-informed datasets of TROs that a) limited the number of TROs to the same density as the 2014 San Francisco (SF) policy (Policy 1), b) set the minimum distance to 500 feet between TROs from a school and from other TROs (Policy 2), c) restricted the types of TROs to exclude pharmacies (Policy 3), and d) a combination of Policies 1-3 (Policy 4). We estimated the effects of each policy individually and in a separate model with their combined effects in terms of the reduction on cotinine levels and health care utilization, as measured by number of visits to the emergency department (ED). We found that the hypothetical policies were likely to be effective in reducing maternal cotinine and ED visits, with the majority of the mothers in the dataset demonstrating reductions in these outcomes after implementation of the policies. We found that Policy 1 led to moderate reductions in TRO exposure for the majority of the sample as well as stratified by race/ethnicity. Additionally, Policy 4 had slightly larger estimated effects than Policy 1, but could be more onerous to implement in practice. Overall, we identified evidence supporting the efficacy of TRO reduction strategies that could impact smoke exposure during pregnancy in our diverse sample in North Carolina.


Asunto(s)
Cotinina , Humanos , Femenino , Embarazo , North Carolina , Contaminación por Humo de Tabaco/prevención & control , Aceptación de la Atención de Salud , Productos de Tabaco , Atención Perinatal , Política de Salud , Comercio
4.
Cancer Lett ; 603: 217213, 2024 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-39244006

RESUMEN

Nerve invasion (NI) is a characteristic feature of pancreatic cancer. Traditional dichotomous statements on the presence of NI are unreasonable because almost all cases exhibit NI when sufficient pathological sections are examined. The critical implications of NI in pancreatic cancer highlight the need for a more effective criterion. This study included 511 patients, who were categorized into a training group and a testing group at a ratio of 7:3. According to the traditional definition, NI was observed in 91.2 % of patients using five pathological slides in our study. The prevalence of NI increased as more pathological slides were used. The criterion of 'two points of intraneural (endoneural) invasion in the case of four pathological slides' has the highest receiver operating characteristic (ROC) score. Based on this new criterion, NI was proved to be an independent prognostic factor for overall survival (OS) and disease-free survival (DFS) and was also correlated with tumor recurrence (P = 0.004). Interestingly, gemcitabine-based chemotherapy regimen is an independent favorable factor for patients with high NI. In the high NI group, patients who received a gemcitabine-based regimen exhibited a better prognosis than those who did not receive the gemcitabine-based regimen for OS (P = 0.000) and DFS (P = 0.001). In conclusion, this study establishes assessment criteria to evaluate the severity of NI in order to predict patient outcomes.


Asunto(s)
Invasividad Neoplásica , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Anciano , Adulto , Supervivencia sin Enfermedad , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Gemcitabina , Curva ROC , Anciano de 80 o más Años , Pronóstico
5.
Phys Chem Chem Phys ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39229752

RESUMEN

The rapid development of valleytronics makes the application of two-dimensional (2D) transition-metal dichalcogenides (TMDs) in valley electronics important. As a new degree of freedom, valley splitting of TMDs has been achieved and tuned by many methods. Among them, using the magnetic proximity effect (MPE) generated from the interface of 2D van der Waals (vdW) heterostructures stacked with TMDs and one magnetic substrate, valley splitting can be achieved through band edge lifting at the adjacent K/K' valley. However, the comprehensive mechanism and strategy of valley splitting in 2D TMD heterostructures need to be explored ulteriorly. Here, we systematically investigated valley splitting of MX2 in MX2/CrI3 (M = W, Mo; X = S, Se, Te) vdW heterostructures using first-principles approaches. We demonstrated that twisting is an effective method to enhance valley splitting in MX2/CrI3 vdW heterostructures. Furthermore, we also showed a ∼10 times enhancement in valley splitting by changing the stacking patterns between WTe2 and CrI3 layers. We attribute this to the interlayer magnetic and electronic coupling between the two layers of the vdW heterostructure. The present results provide a theoretical basis and effective methods for tuning valley splitting 2D TMD heterostructures.

6.
Artículo en Inglés | MEDLINE | ID: mdl-39269400

RESUMEN

BACKGROUND: The relationship between long-term outcomes and operator experience for left atrial appendage occlusion (LAAO) is still unknown. OBJECTIVES: This study sought to explore the association between operator LAAO experience and one-year clinical outcomes. METHODS: The RECORD study (Registry to Evaluate Chinese Real-World Clinical Outcomes in Patients With AF Using the WATCHMAN Left Atrial Appendage Closure Technology; NCT03917563) was a multicenter, prospective registry that included patients with the WATCHMAN LAAO device (Boston Scientific) in China from April 1, 2019, to October 31, 2020. The current analyses included patients with solely LAAO from the registry; those who had concomitant LAAO and ablation/other procedures were excluded. The primary outcome was a composite endpoint of death, stroke, systemic embolism, and Bleeding Academic Research Consortium (BARC)-defined type 3 or 5 bleeding at 1 year. RESULTS: A total of 1,547 LAAO patients and 111 operators were included. The mean ± SD CHA2DS2-VASc and HAS-BLED scores of patients were 4.0 ± 1.8 and 2.5 ± 1.1, respectively. The mean ± SD age of operators was 47.0 ± 7.2 years, 15 (13.5%) were female, and 52 (46.8%) were electrophysiologists. Utilizing maximally selected log-rank statistics, the thresholds to categorize an experienced operator were performing ≥32 LAAOs annually or ≥134 LAAOs in total. Performing ≥32 LAAOs annually is the better criterion than ≥134 LAAOs in total (absolute net reclassification index: 25.79%; P < 0.001). Compared with the ≥32 LAAO annually group, the <32 group was associated with a 1.8-fold (HRadjusted: 1.79; 95% CI: 1.16-2.78; P = 0.009) increase in the risk of the primary endpoint, and such risk in the <32 group can be reduced by ∼12% after performing each additional 5 cases (HRadjusted per 5 cases: 0.88; 95% CI: 0.78-0.99; P = 0.033). CONCLUSIONS: Performing ≥32 LAAOs annually could be a threshold to categorize an experienced operator. Before reaching this threshold, the risk of death, stroke, systemic embolism, and BARC-defined type 3 or 5 bleeding decreased by 12% after every 5 cases performed.

7.
Front Neurosci ; 18: 1406135, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39221007

RESUMEN

Background: Transcutaneous Vagal Nerve Stimulation (tVNS) has been used as a promising noninvasive neuromodulation technique for the treatment of various systems.The aim of this study was to analyze the research hotspots and future directions of tVNS in the 21st century by using bibliometric methods. Methods: The study object was the literature related to tVNS from the Web of Science database from 2000 to May 2024. In order to measure and analyze the number of literature issuance, institutions, authors, countries, keywords, co-citations, and journals of publication, we used VOSviewer, Citespace, Bibliometrix R-package, and Scimago Graphica software. A narrative review of the current research content of tVNS was conducted to gain a better understanding of the current state of the field. Results: A total of 569 papers were included in the study. The results show that from 2000 to 2024, the number of publications shows an increasing trend year by year, involving a total of 326 research institutions. The United States, China, and Germany are the major research centers. The study identified 399 keywords, which roughly formed 11 natural clusters, revealing that the current hotspots of related research are mainly reflected in 3 areas: intervention efficacy on nervous system diseases, mechanism of action of tVNS, and stimulation mode of tVNS. The top 10 most cited references focus on research into the mechanism of action of tVNS. Conclusion: The efficacy and safety of tVNS have been confirmed in previous studies, but a standardized tVNS treatment protocol has not yet been developed, and most clinical studies have small sample sizes and lack multicenter and multidisciplinary collaboration. Currently, tVNS is used in the treatment of neurological diseases, psychiatric diseases, cardiovascular diseases, and some autoimmune diseases. It is expected that future research in this field will continue to focus on the application of tVNS in central nervous system diseases and the exploration of related mechanisms, and at the same time, with the rise of non-invasive neuromodulation technology, the application of tVNS in other diseases also has great potential for development.

8.
Int Immunopharmacol ; 140: 112874, 2024 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-39116498

RESUMEN

OBJECTIVE: Colorectal cancer (CRC), specifically colon adenocarcinoma, is the third most prevalent and the second most lethal form of cancer. Anoikis is found to be specialized form of programmed cell death (PCD), which plays a pivotal role in tumor progression. This study aimed to investigate the role of the anoikis related genes (ARGs) in colon cancer. METHODS: Consensus unsupervised clustering, differential expression analysis, tumor mutational burden analysis, and analysis of immune cell infiltration were utilized in the study. For the analysis of RNA sequences and clinical data of COAD patients, data from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) were obtained. A prognostic scoring system for overall survival (OS) prediction was developed using Cox regression and LASSO regression analysis. Furthermore, loss-of-function assay was utilized to explore the role of RAD9A played in the progression of colon cancer. RESULTS: The prognostic value of a risk score composed of NTRK2, EPHA2, RAD9A, CDC25C, and SNAI1 genes was significant. Furthermore, these findings suggested potential mechanisms that may influence prognosis, supporting the development of individualized treatment plans and management of patient outcomes. Further experiments confirmed that RAD9A could promote proliferation and metastasis of colon cancer cells. These effects may be achieved by affecting the phosphorylation of AKT. CONCLUSION: Differences in survival time and the tumor immune microenvironment (TIME) were observed between two gene clusters associated with ARGs. In addition, a prognostic risk model was established and confirmed as an independent risk factor. Furthermore, our data indicated that RAD9A promoted tumorigenicityby activating AKT in colon cancer.


Asunto(s)
Anoicis , Neoplasias del Colon , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias del Colon/genética , Neoplasias del Colon/mortalidad , Neoplasias del Colon/patología , Neoplasias del Colon/inmunología , Anoicis/genética , Pronóstico , Línea Celular Tumoral , Masculino , Proliferación Celular , Animales , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Femenino
9.
Environ Sci Technol ; 58(36): 15997-16005, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39190315

RESUMEN

Epidemiologic evidence has emerged showing an association between exposure to air pollution and increased risks of gestational diabetes mellitus (GDM). This study examines the effect of low-level air pollution exposure on a subclinical biomarker of hyperglycemia (i.e., HbA1c) in pregnant people without diabetes before conception. We measured HbA1c in 577 samples repeatedly collected from 224 pregnant people in Rochester, NY, and estimated residential concentrations of PM2.5 and NO2 using high-resolution spatiotemporal models. We observed a U-shaped trajectory of HbA1c during pregnancy with average HbA1c levels of 5.13 (±0.52), 4.97 (±0.54), and 5.43 (±0.40)% in early-, mid-, and late pregnancy, respectively. After adjustment for the U-shaped trajectory and classic GDM risk factors, each interquartile range increase in 10 week NO2 concentration (8.0 ppb) was associated with 0.09% (95% CI: 0.02 to 0.16%) and 0.18% (95% CI: 0.08 to 0.28%) increases in HbA1c over the entire pregnancy and in late pregnancy, respectively. These associations remained robust among participants without GDM. Using separate distributed lag models, we identified a period between 8th and 14th gestational weeks as critical windows responsible for increased levels of HbA1c measured at 14th, 22nd, and 30th gestational weeks. Our results suggest that low-level air pollution contributes to hyperglycemia in medically low-risk pregnant people.


Asunto(s)
Contaminación del Aire , Biomarcadores , Diabetes Gestacional , Hiperglucemia , Humanos , Embarazo , Femenino , Hiperglucemia/sangre , Adulto , Contaminantes Atmosféricos , Hemoglobina Glucada , Material Particulado , Exposición a Riesgos Ambientales
11.
Front Cardiovasc Med ; 11: 1384546, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39193498

RESUMEN

Background: Acute coronary syndrome (ACS) is a leading cause of morbidity and mortality worldwide. In recent years, ACS has been reported to be associated with age, and the incidence has become more common in younger patients. Previous studies have identified various risk factors that contribute to the stratification of ACS patients. However, it remains unclear whether these risk factors, along with proteomic and clinical characteristics, are applicable to young ACS patients, as they are for middle-aged and elderly patients. This study aimed to investigate the proteomics, risk factors, and clinical characteristics of young ACS patients, as well as the differences between them and middle-aged and elderly ACS patients. By comparing these findings with those of middle-aged and elderly patients, we aimed to identify any discrepancies and these findings possibly may have implications for future management strategies of this specific population. Methods: This observational study included a total of 187 participants diagnosed with ACS and 17 young healthy individuals as the control group. ACS patients were divided into three age groups: <45 years old, 45-60 years old, and 61-75 years old. The control group consisted of healthy individuals under the age of 45 who underwent coronary angiography and were excluded from CAD. We collected clinical characteristics, laboratory data, and echocardiographic results from each participant. Additionally, blood samples were collected for further analysis of relevant proteomic and arteriosclerosis marker data using proteomics analysis. Results: Our findings revealed that the presence of certain key factors was associated with a significantly difference in patients with ACS aged younger than 45 years, and this association differed from that of traditional cardiovascular risk factors in patients older than 45 years. Specifically, a higher body mass index and hyperlipidemia were found to be associated with an increased risk of ACS morbidity in young adults (<45 years old) compared to middle-aged and elderly individuals. Furthermore, our findings indicated that the expression levels of growth differentiation factor 15, osteopontin, and NT-proBNP were significantly different among the groups. Conclusion: In summary, our study revealed that the main pathogenic factors of ACS patients under 45 years of age differed from those of middle-aged and elderly patients. These findings may contribute to the prevention and treatment strategies for young patients with ACS.

12.
Curr Med Sci ; 44(4): 692-697, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39096480

RESUMEN

OBJECTIVE: Inflammation is involved in the development and progression of nonalcoholic fatty liver disease (NAFLD). The monocyte to high-density lipoprotein cholesterol ratio (MHR) has emerged as a marker for various inflammation-related diseases. The aim of the present study was to investigate the association between the MHR and NAFLD in a population with childhood obesity. METHODS: Based on hepatic ultrasound, a total of 504 children with obesity (357 with NAFLD and 147 without NAFLD) were included in the study. The correlation between the MHR and NAFLD risk factors was assessed by Pearson's and Spearman's analyses. Multivariate stepwise logistic regression analyses were conducted to explore the association between the MHR and the risk of NAFLD. RESULTS: The MHR in patients with NAFLD was significantly greater than that in patients without NAFLD [0.52 (0.44-0.67) versus 0.44 (0.34-0.57), P<0.001]. Multivariate stepwise logistic regression analysis demonstrated that the MHR [odds ratio (OR): 1.033, 95% confidence interval (CI): 1.015-1.051; P<0.001] was an independent predictor of NAFLD in childhood obesity patients, as were age (OR: 1.205, 95% CI: 1.059-1.371; P=0.005], waist circumference [OR: 1.037, 95% CI: 1.008-1.067; P=0.012], and alanine transaminase [OR: 1.067, 95% CI: 1.045-1.089; P<0.001]. Additionally, MHR quartiles showed a significant positive association with the incidence of NAFLD after adjusting for potential confounding factors. CONCLUSION: The present study showed that the MHR may serve as an available and useful indicator of NAFLD in individuals with childhood obesity.


Asunto(s)
HDL-Colesterol , Monocitos , Enfermedad del Hígado Graso no Alcohólico , Obesidad Infantil , Humanos , Enfermedad del Hígado Graso no Alcohólico/sangre , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Masculino , Femenino , Obesidad Infantil/sangre , Obesidad Infantil/epidemiología , Obesidad Infantil/complicaciones , Niño , HDL-Colesterol/sangre , Monocitos/metabolismo , Factores de Riesgo , Biomarcadores/sangre , Adolescente
13.
Sci Total Environ ; 951: 175148, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39089388

RESUMEN

BACKGROUND: Exposure to air pollution has been associated with increased risks of cardiopulmonary diseases, cancer, and mortality, whereas residing near green spaces may reduce the risks. However, limited research explores their combined effect on oxidative stress. METHODS: A total of 251 participants with multi-time measurements were included in the longitudinal-designed study. Personal gaseous air pollutants (CO, NO, NO2, and O3,) and particulate pollution (PM1, PM2.5, and PM10) were measured and followed in two 7-day windows while ambient exposure levels and urine samples were collected simultaneously. Participants' Normalized Difference Vegetation Index (NDVI) was estimated and used to represent greenness exposure. Urinary oxidative stress biomarkers include free malondialdehyde (MDA), total MDA, and 8-hydroxydeoxyguanosine (8-OHdG). Linear mixed-effects models were used to independently and jointly estimate the associations of greenness and air pollution with oxidative stress biomarkers. RESULTS: We found consistent positive associations of personal ozone (O3) exposure with 8-OHdG percent changes, and this association was modified by gender and outdoor activity frequency. Consistent positive associations of personal lag 2-day carbon monoxide (CO) exposure with the percent changes of the three oxidative stress biomarkers were significant. We additionally observed that individuals who lived in greener areas had lower levels of urinary-free and total MDA. Participants in the highest NDVI tertile had 0.38 and 0.46 lower free and total MDA levels, [95 % CI: (-0.70, -0.05) and (-0.78, -0.13)], compared to the lowest NDVI tertile. There was also evidence indicating the modification effects by area, education, and outdoor activity frequency on associations between NDVI exposure and creatinine adjusted free MDA (all Pfor interaction < 0.05). Additional greenness modification effects on personal O3 exposure with urinary 8-OHdG was observed. CONCLUSION: Our study provides biological evidence of the modification effect of the built environment on the impact of air pollution.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Exposición a Riesgos Ambientales , Estrés Oxidativo , Humanos , Contaminación del Aire/estadística & datos numéricos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Contaminantes Atmosféricos/análisis , Masculino , Femenino , Beijing , Adulto , Material Particulado/análisis , Biomarcadores/orina , Persona de Mediana Edad , Monitoreo del Ambiente , 8-Hidroxi-2'-Desoxicoguanosina , Estudios Longitudinales
14.
Front Neurol ; 15: 1372159, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39131051

RESUMEN

Background: Repetitive transcranial magnetic stimulation (rTMS), as an emerging non-invasive neuromodulation technique, is now widely employed in rehabilitation therapy. The purpose of this paper is to comprehensively summarize existing evidence regarding rTMS intervention for lower limb motor function in patients at different stages of stroke. Methods: A systematic search was conducted to identify randomized controlled trials (RCTs) assessing the efficacy of rTMS for treating lower limb motor dysfunction after stroke. Multiple databases, including China National Knowledge Infrastructure (CNKI), Wanfang Data Knowledge Service Platform, VIP Database, PubMed, Embase, Web of Science, and Cochrane Library, were searched. The search period extended from the inception of the libraries to June 2024. Literature information was extracted, and methodological quality was evaluated using the risk of bias assessment tool in the Cochrane Handbook. Meta-analysis was performed using Stata 17.0 software. Results: Overall, 49 appropriate studies (including 3,558 stroke subjects) were found. Meta-analysis results demonstrated that rTMS effectively improved lower limb motor function across all stages of stroke. The intervention was particularly more effective in patients in the subacute stage than in the acute or chronic stages. Subgroup analysis revealed that, for acute-stage patients, low-frequency stimulation targeting the M1 or DLPFC brain regions on the unaffected side with 20-40 sessions significantly improved FMA-LE scores. In subacute-phase patients, low-frequency stimulation targeting the M1 brain regions on the unaffected side with 18 sessions significantly improved FMA-LE scores. The results demonstrated that HF-rTMS was more effective than LF-rTMS in improving walking speed, with the greatest efficacy observed at 20 sessions. While for enhancing gait balance in stroke patients, LF-rTMS with the best therapeutic effect was observed at a frequency of 20-40 treatments. Conclusion: This study demonstrates the efficacy of rTMS in improving lower limb motor function, balance, and walking speed in stroke patients at various stages. The findings provide a valuable reference for the development of optimized rTMS treatment plans in clinical practice.Systematic review registration: PROSPERO: CRD42023466094.

15.
Small ; : e2403098, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39162110

RESUMEN

To meet the ever-increasing demand of proton exchange membrane fuel cell (PEMFC), it is necessary to carry out structure optimization for low-cost and high-stability oxygen reduction reaction (ORR) catalysts. Herein, a zeolitic imidazolate framework (ZIF)-derived carbon material with a mass of heteroatoms and defects is developed and serves as advanced support for nano-Pt-based ORR catalysts. This unique structure enhances the interaction between nano-Pt and support, leading to higher ORR intrinsic activity. During fuel cell applications, it demonstrates impressive water-retaining capacity and electrochemical stability. Under H2-O2 supply without cathode humidification, this catalyst achieves high mass activity of 0.475 A mgPt -1, with only 7.4% attenuation in maximum power density after 20 000 cycles of accelerated durability test, highlighting its remarkable potential for fuel cell applications. Physicochemical characterization and theoretical simulation reveal the crucial anchoring effect of heteroatom-doped defects to nano-Pt, providing valuable insights for further ORR catalyst design and PEMFC applications.

16.
Sci Bull (Beijing) ; 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39181785

RESUMEN

Exposure to polycyclic aromatic hydrocarbons (PAHs) in the Chinese population was among the highest globally and associated with various adverse effects. This study examines the impact of China's two-phase clean air initiatives, namely the Air Pollution Prevention and Control Action Plan (APPCAP) in 2013-2017 and the Blue-Sky Defense War (BSDW) in 2018-2020, on PAH levels and human exposures in Beijing. To evaluate the effects of APPCAP, we measured 16 PAHs in 287 PM2.5 samples collected in Beijing and 9 PAH metabolites in 358 urine samples obtained from 54 individuals who traveled from Los Angeles to Beijing between 2014 and 2018. The concentration of PM2.5-bound benzo[a]pyrene equivalents (BaPeq) decreased by 88.5% in 2014-2018 due to reduced traffic, coal, and biomass emissions. PAH metabolite concentrations in travelers' urine decreased by 52.3% in Beijing, correlated with changes in PM2.5 and NO2 levels. In contrast, no significant changes were observed in Los Angeles. To evaluate BSDW's effects, we collected 123 additional PM2.5 samples for PAH measurements in 2019-2021. We observed sustained reductions in BaPeq concentrations attributable to reductions in coal and biomass emissions during the BSDW phase, but those from traffic sources remained unchanged. After accounting for meteorological factors, China's two-phase clean air initiatives jointly reduced Beijing's PM2.5-bound BaPeq concentrations by 96.6% from 2014 to 2021. These findings provide compelling evidence for the effectiveness of China's clean air actions in mitigating population exposure to PAHs in Beijing.

17.
Front Pharmacol ; 15: 1378081, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39175547

RESUMEN

Introduction: Fospropofol disodium is a novel prodrug that has improved pharmacokinetic and pharmacodynamic properties when compared with propofol. This trial aims to compare the efficacy and safety of fospropofol versus propofol sedation for same-day bidirectional endoscopy in elderly patients. Methods and analysis: This is a prospective, single-center, double-blind, randomized, propofol-controlled, non-inferiority trial. A total of 256 patients aged 65 years or older, who are scheduled for same-day bidirectional endoscopy under sedation, will be randomly allocated, in a 1:1 ratio, to either fospropofol group or propofol group (n = 128 in each group). All patients will receive analgesic pre-treatment with sufentanil 5 µg. Two minutes later, an initial bolus dose of fospropofol 6.5 mg/kg or 1.5 mg/kg propofol and supplemental doses of fospropofol 1.6 mg/kg or 0.5 mg/kg propofol will be titrated as needed to achieve target sedation levels during the procedures. The primary outcome is the success rate of same-day bidirectional endoscopy. Secondary outcomes include the time to successful induction of sedation, duration, time to being fully alert, time to patient discharge, endoscopist satisfaction, patient satisfaction, and the top-up frequency and dosage of sedative medications. The safety endpoints consist of adverse events concerning cough reflex, gag reflexes, body movement, muscular tremor, and pain on injection. Sedation-related AEs, including episodes of desaturation, severe desaturation (SpO2 < 90%), hypotension, severe hypotension (decrease in MBP ≥30% of baseline), and bradycardia, will also be recorded. Data will be analyzed on an intention-to-treat basis. Discussion: We hypothesize that the efficacy and safety of fospropofol sedation for elderly patients undergoing same-visit bidirectional endoscopy will not be inferior to that of propofol. Our findings will potentially provide a new sedation regimen for same-visit bidirectional endoscopy in elderly patients. Clinical Trial Registration: clinicaltrials.gov, identifier NCT02875639.

18.
Front Neurosci ; 18: 1392002, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39099634

RESUMEN

Background: Acupuncture, as an alternative and complementary therapy recommended by the World Health Organization for stroke treatment, holds potential in ameliorating neurofunctional deficits induced by ischemic stroke (IS). Understanding the immediate and long-term effects of acupuncture and their interrelation would contribute to a better comprehension of the mechanisms underlying acupuncture efficacy. Methods: Activation likelihood estimation (ALE) meta-analysis was used to analyze the brain activation patterns reported in 21 relevant functional neuroimaging studies. Among these studies, 12 focused on the immediate brain activation and 9 on the long-term activation. Single dataset analysis were employed to identify both immediate and long-term brain activation of acupuncture treatment in IS patients, while contrast and conjunction analysis were utilized to explore distinctions and connections between the two. Results: According to the ALE analysis, immediately after acupuncture treatment, IS patients exhibited an enhanced cluster centered around the right precuneus (PCUN) and a reduced cluster centered on the left middle frontal gyrus (MFG). After long-term acupuncture treatment, IS patients showed an enhanced cluster in the left PCUN, along with two reduced clusters in the right insula (INS) and hippocampus (HIP), respectively. Additionally, in comparison to long-term acupuncture treatment, the right angular gyrus (ANG) demonstrated higher ALE scores immediately after acupuncture, whereas long-term acupuncture resulted in higher scores in the left superior parietal gyrus (SPG). The intersecting cluster activated by both of them was located in the left cuneus (CUN). Conclusion: The findings provide initial insights into both the immediate and long-term brain activation patterns of acupuncture treatment for IS, as well as the intricate interplay between them. Both immediate and long-term acupuncture treatments showed distinct patterns of brain activation, with the left CUN emerging as a crucial regulatory region in their association. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, CRD42023480834.

19.
Front Bioeng Biotechnol ; 12: 1439883, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39104624

RESUMEN

Most colon cancer patients are diagnosed at an advanced stage, with a grim prognosis. In clinical, various combination therapies have been employed to enhance the efficacy of colon cancer treatment. The essence of combined treatment is the judicious selection and combination of various treatment units. Phototherapy (PT), sonodynamic therapy (SDT), and chemotherapy are treatment modalities that rely on the active molecules to treat tumors, and have been demonstrated to synergistically enhance tumor treatment efficacy. However, the differences in the metabolism of active molecules and hypoxic microenvironment of tumors have limited the synergistic effects of the aforementioned methods. To address this significant issue, in this study, we utilized polydopamine (PDA) as the encapsulated material to form a rigid shell that contains the therapeutic molecules IR-780 and methotrexate (MTX) on the surface of perfluorohexane (PFH) microdroplets through self-assembling method to develop an SDT/chemotherapy/PT combined nanoparticles (SCP NPs). Transmission electron microscopy (TEM) revealed that the nanoparticles exhibited a hollow shell structure, with an average size of approximately 100 nm. SCP NPs have excellent stability and biocompatibility in both in vitro and in vivo. The absorption and emission spectrum of the loaded IR-780 did not exhibit any significant shift, and the photothermal temperature rose to 92°C. Their ultrasonic cavitation effect was good and their cell inhibitory effect of MTX was maintained. SCP NPs can achieve multi-modal triggered release through ultrasound, laser irradiation, and pH, ensuring a simultaneous accumulation of therapeutic molecules in the tumor area and effectively alleviating tumor hypoxia. Additionally, both the near-infrared fluorescence (NIF) signal and the ultrasonic cavitation signal of the nanoparticles can be utilized for tracking and monitoring treatment efficacy. Most notably, SCP NPs exhibited outstanding synergistic treatment effects at low intervention levels, resulting in a 67% cure rate of tumors. These results provide an experimental basis for developing the new clinical treatments for colon cancer.

20.
Phys Chem Chem Phys ; 26(32): 21801-21809, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39101765

RESUMEN

Lead-free halide perovskites have recently garnered significant attention due to their rich structural diversity and exceptionally ultralow lattice thermal conductivity (κL). Here, we employ first-principles calculations in conjunction with self-consistent phonon theory and Boltzmann transport equations to investigate the crystal structure, electronic structure, mechanical properties, and κLs of two typical vacancy-ordered halide perovskites, denoted with the general formula Cs3Bi2X9 (X = Br, I). Ultralow κLs of 0.401 and 0.262 W mK-1 at 300 K are predicted for Cs3Bi2Br9 and Cs3Bi2I9, respectively. Our findings reveal that the ultralow κLs are mainly associated with the Cs rattling-like motion, vibrations of halide polyhedral frameworks, and strong scattering in the acoustic and low-frequency optical phonon branches. The structural analysis indicates that these phonon dynamic properties are closely relevant to the bonding hierarchy. The presence of the extended Bi-X antibonding states at the valence band maximum contributes to the soft elastic lattice and low phonon group velocities. Compared to Cs3Bi2Br9, the face-sharing feature and weaker bond strength in Cs3Bi2I9 lead to a softer elasticity modulus and stronger anharmonicity. Additionally, we demonstrate the presence of wave-like κC in Cs3Bi2X9 by evaluating the coherent contribution. Our work provides the physical microscopic mechanisms of the wave-like κC in two typical lead-free halide perovskites, which are beneficial to designing intrinsic materials with the feature of ultralow κL.

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