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1.
J Stroke Cerebrovasc Dis ; : 107908, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39094717

RESUMEN

OBJECTIVES: Our aim is to evaluate the impact of surface ultraviolet radiation intensity on hospital admissions for stroke and to compare the correlation and differences among different subtypes of strokes. MATERIALS AND METHODS: We collected daily data on surface ultraviolet radiation intensity, temperature, air pollution, and hospital admissions for stroke in Harbin from 2015 to 2022. Using a distributed lag non-linear model, we determined the correlation between daily surface ultraviolet radiation intensity and the stroke admission rate. Relative risks (RR) with 95% confidence intervals (CI) and attributable fractions (AF) with 95% CI were calculated based on stroke subtypes, gender, and age groups. RESULTS: A total of 132,952 hospitalized stroke cases (including hemorrhagic and ischemic strokes) were included in the study. We assessed the non-linear effects of ultraviolet intensity on hospitalized patients with ischemic and hemorrhagic strokes. Compared to the maximum morbidity benchmark ultraviolet intensity (19.2 × 10^5 for ischemic stroke and 20.25 for hemorrhagic stroke), over the 0-10 day lag period, the RR for extreme low radiation (1st percentile) was 0.86 (95% CI: 0.77, 0.96), and the RR for extreme high radiation (99th percentile) was 0.86 (95% CI: 0.77, 0.96). In summary, -4.842% (95% CI: -7.721%, -2.167%) and -1.668% (95% CI: -3.061%, -0.33%) of ischemic strokes were attributed to extreme low radiation intensity with a lag of 0 to 10 days and extreme high radiation intensity with a lag of 0 to 5 days, respectively. The reduction in stroke hospitalization rates due to low or high ultraviolet intensity was more pronounced in females and younger individuals compared to males and older individuals. None of the mentioned ultraviolet intensity intensities and lag days had a statistically significant impact on hemorrhagic stroke. CONCLUSIONS: Our study fundamentally suggests that both lower and higher levels of surface ultraviolet radiation intensity in Harbin, China, contribute to a reduced incidence of ischemic stroke, with this effect lasting approximately 10 days. This finding holds significant potential for public health and clinical relevance.

2.
Cancer Med ; 13(11): e7364, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38847084

RESUMEN

PURPOSE: Lung cancer (LC) and breast cancer (BC) are the most common causes of brain metastases (BMs). Time from primary diagnosis to BM (TPDBM) refers to the time interval between initial LC or BC diagnosis and development of BM. This research aims to identify clinical, molecular, and therapeutic risk factors associated with shorter TPDBM. METHODS: We retrospectively reviewed all diagnosed LC and BC patients with BM at Harbin Medical University Cancer Hospital from 2016 to 2020. A total of 570 patients with LC brain metastasis (LCBM) and 173 patients with breast cancer brain metastasis (BCBM) patients who met the inclusion criteria were enrolled for further analysis. BM free survival time curves were generated using Kaplan-Meier analyses. Univariate and multivariate Cox regression analyses were applied to identify risk factors associated with earlier development of BM in LC and BC, respectively. RESULTS: The median TPDBM was 5.3 months in LC and 44.4 months in BC. In multivariate analysis, clinical stage IV and M1 stage were independent risk factors for early development of LCBM. LC patients who received chemotherapy, targeted therapy, pulmonary radiotherapy, and pulmonary surgery had longer TPDBM. For BC patients, age ≥ 50 years, Ki67 ≥ 0.3, HER2 positive or triple-negative breast cancer subtype, advanced N stage, and no mastectomy were correlated with shorter TPDBM. CONCLUSIONS: This single-institutional study helps identify patients who have a high risk of developing BM early. For these patients, early detection and intervention could have clinical benefits.


Asunto(s)
Neoplasias Encefálicas , Neoplasias de la Mama , Neoplasias Pulmonares , Humanos , Femenino , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/diagnóstico , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/diagnóstico , Persona de Mediana Edad , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Estudios Retrospectivos , Factores de Riesgo , Anciano , Masculino , Factores de Tiempo , Adulto , Estadificación de Neoplasias
3.
Int J Biol Macromol ; 274(Pt 2): 133434, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38936570

RESUMEN

This study aimed to evaluate the influence of ultrasonic degradation on the physicochemical and biological characteristics of Polygonatum cyrtonema polysaccharide (PCP, 8.59 kDa). PCP was subjected to ultrasonic treatment for 8, 16, and 24 h and yielded the degraded fractions PCP-8, PCP-16, and PCP-24 (5.06, 4.13, and 3.69 kDa), respectively. Compared with the intact PCP, PCP-8, PCP-16 and PCP-24 had a reduced particle size (decrements of 28.03 %, 46.15 % and 62.54 %, respectively). Although ultrasonic degradation did not alter the primary structure of PCP, its triple helical and superficial structures were disrupted, with degraded fractions demonstrating reduced thermal stability and apparent viscosities compared with those of the intact PCP. Furthermore, the functional properties of the degraded fractions were different. PCP-16 most favourably affected GLP-1 secretion, while PCP-8 and PCP-24 exhibited the strongest antioxidant and enzyme inhibitory activities, respectively. Hence, controlled ultrasound irradiation is an appealing approach for partially degrading PCP and enhancing its bioactivity as a functional agent.


Asunto(s)
Antioxidantes , Péptido 1 Similar al Glucagón , Polygonatum , Polisacáridos , Ondas Ultrasónicas , Animales , Antioxidantes/química , Antioxidantes/farmacología , Péptido 1 Similar al Glucagón/metabolismo , Tamaño de la Partícula , Polygonatum/química , Polisacáridos/química , Polisacáridos/farmacología , Viscosidad
4.
Phytother Res ; 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38818771

RESUMEN

Doxorubicin (Dox) is a highly effective anti-neoplastic agent. Still, its utility in the clinic has been hindered by toxicities, including vomiting, hematopoietic suppression and nausea, with cardiotoxicity being the most serious side effect. Genistein (Gen) is a natural product with extensive biological effects, including anti-oxidation, anti-tumor, and cardiovascular protection. This study evaluated whether Gen protected the heart from Dox-induced cardiotoxicity and explored the underlying mechanisms. Male Sprague-Dawley (SD) rats were categorized into control (Ctrl), genistein (Gen), doxorubicin (Dox), genistein 20 mg/kg/day + doxorubicin (Gen20 + Dox) and genistein 40 mg/kg/day + doxorubicin (Gen40 + Dox) groups. Six weeks after injection, immunohistochemistry (IHC), transmission electron microscopy (TEM), and clinical cardiac function analyses were performed to evaluate the effects of Dox on cardiac function and structural alterations. Furthermore, each heart histopathological lesions were given a score of 0-3 in compliance with the articles for statistical analysis. In addition, molecular and cellular response of H9c2 cells toward Dox were evaluated through western blotting, Cell Counting Kit-8 (CCK8), AO staining and calcein AM/PI assay. Dox (5 µM in vitro and 18 mg/kg in vivo) was used in this study. In vivo, low-dose Gen pretreatment protected the rat against Dox-induced cardiac dysfunction and pathological remodeling. Gen inhibited extracellular signal-regulated kinase1/2 (ERK1/2)'s phosphorylation, increased the protein levels of STAT3 and c-Myc, and decreased the autophagy and apoptosis of cardiomyocytes. U0126, a MEK1/2 inhibitor, can mimic the effect of Gen in protecting against Dox-induced cytotoxicity both in vivo and in vitro. Molecular docking analysis showed that Gen forms a stable complex with ERK1/2. Gen protected the heart against Dox-induced cardiomyocyte autophagy and apoptosis through the ERK/STAT3/c-Myc signaling pathway.

5.
Langmuir ; 40(9): 4992-5000, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38391390

RESUMEN

Aqueous two-phase systems (ATPS) are considered a new type of green separation system, but their low selectivity to target molecules limits their practical application. In this study, we used surfactant@MWCNT as an adjuvant to improve the selectivity of PEG/(NH4)2SO4 ATPS. The surfactants used include Triton X-100 (TX-100), Tween 80, sodium dodecyl sulfate (SDS), sodium dodecyl benzenesulfonate (SDBS), and bis(2-ethylhexyl)sulfosuccinate sodium salt (AOT). Nine aromatic compounds, including syringic acid, vanillin, tryptophan, phenylalanine, tyrosine, mandelic acid, theophylline, theobromine, and cephalexin, were selected as model extracts. The results showed that the use of the surfactant@MWCNT composite as an adjuvant significantly improved the selectivity of the ATPS toward syringic acid among the nine extracts. Moreover, the selectivity of the ATPS for syringic acid with the TX-100/MWCNT composite as the adjuvant is better than that with the Tween 80/MWCNT composite as the adjuvant, followed by that with the anionic surfactant/MWCNT composite as the adjuvant. The enhanced selectivity of ATPS by the surfactant/MWCNT composite is ascribed to the spatial effect and the electrostatic and hydrophobic interactions between the extract and the surfactant adsorbed on the MWCNT.

6.
Neurochem Res ; 49(3): 771-784, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38102342

RESUMEN

The aversion to cold is a fundamental motivated behavior that contributes to the body temperature homeostasis. However, the involvement of the lateral habenula (LHb) as a regulatory hub for negative emotions in this physiological process remains uninvestigated. In this study, we demonstrate an elevation in the population activity of LHb neurons following exposure to cold stimuli. Additionally, we establish the necessity of Vglut2-expressing neurons within the LHb for the encoding of cold aversion behaviors. Furthermore, we have elucidated a neural circuit from excitatory neurons of the dorsomedial hypothalamus (DMH) to LHb that plays a crucial role in this progress. Manipulation of the DMH-LHb circuit has a significant impact on cold aversion behavior in mice. It is worth noting that this circuit does not exhibit any noticeable effects on autonomic thermoregulation or depression-like behavior. The identification of these neural mechanisms involved in behavioral thermoregulation provides a promising avenue for future research.


Asunto(s)
Habénula , Ratones , Animales , Habénula/fisiología , Reacción de Prevención/fisiología , Neuronas/fisiología
7.
J Mol Neurosci ; 73(11-12): 921-931, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37864623

RESUMEN

We aimed to investigate the mechanism underlying the roles of miRNA-377, Cystathionine-ß-synthase (CBS), and hydrogen sulfide (H2S) in the development of hypoxic-ischemic encephalopathy (HIE). We investigated the relationship between CBS, H2S, and miR-377 in both humans with HIE and animals with hypoxic-ischemic insult. An animal model of fetal rats with hypoxic-ischemic brain injury was established, and the fetal rats were randomly assigned to control and hypoxic-ischemic groups for 15 min (mild) and 30 min (moderate) groups. Human samples were collected from children diagnosed with HIE. Healthy or non-neurological disease children were selected as the control group. Hematoxylin-eosin (HE) staining, quantitative real-time polymerase chain reaction (qRT-PCR), enzyme-linked immunosorbent assay (ELISA), and western blot were used to conduct this study. Hypoxia-ischemia induced pathological alterations in brain tissue changes were more severe in groups with severe hypoxic insult. miRNA-377 expression levels were upregulated in brain tissue and serum of fetal rats and human samples with HIE compared to controls. Conversely, CBS and H2S expression levels were significantly decreased in both human and animal samples compared to controls. Our findings suggest that CBS is a target gene of miR-377 which may contribute to the development of HIE by regulating CBS/H2S. H2S has a protective effect against hypoxic damage in brain tissue. The study provides new insights into the potential mechanisms underlying the protective role of H2S in hypoxic brain damage and may contribute to the development of novel therapies for HIE.


Asunto(s)
Sulfuro de Hidrógeno , Hipoxia-Isquemia Encefálica , MicroARNs , Niño , Humanos , Ratas , Animales , MicroARNs/genética , MicroARNs/metabolismo , Hipoxia-Isquemia Encefálica/genética , Cistationina , Cistationina betasintasa/genética , Cistationina betasintasa/metabolismo , Ratas Sprague-Dawley , Sulfuro de Hidrógeno/metabolismo
8.
Front Immunol ; 14: 1233260, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37799714

RESUMEN

Background: Disulfidptosis is a newly identified variant of cell death characterized by disulfide accumulation, which is independent of ATP depletion. Accordingly, the latent influence of disulfidptosis on the prognosis of lung adenocarcinoma (LUAD) patients and the progression of tumors remains poorly understood. Methods: We conducted a multifaceted analysis of the transcriptional and genetic modifications in disulfidptosis regulators (DRs) specific to LUAD, followed by an evaluation of their expression configurations to define DR clusters. Harnessing the differentially expressed genes (DEGs) identified from these clusters, we formulated an optimal predictive model by amalgamating 10 distinct machine learning algorithms across 101 unique combinations to compute the disulfidptosis score (DS). Patients were subsequently stratified into high and low DS cohorts based on median DS values. We then performed an exhaustive comparison between these cohorts, focusing on somatic mutations, clinical attributes, tumor microenvironment, and treatment responsiveness. Finally, we empirically validated the biological implications of a critical gene, KYNU, through assays in LUAD cell lines. Results: We identified two DR clusters and there were great differences in overall survival (OS) and tumor microenvironment. We selected the "Least Absolute Shrinkage and Selection Operator (LASSO) + Random Survival Forest (RFS)" algorithm to develop a DS based on the average C-index across different cohorts. Our model effectively stratified LUAD patients into high- and low-DS subgroups, with this latter demonstrating superior OS, a reduced mutational landscape, enhanced immune status, and increased sensitivity to immunotherapy. Notably, the predictive accuracy of DS outperformed the published LUAD signature and clinical features. Finally, we validated the DS expression using clinical samples and found that inhibiting KYNU suppressed LUAD cells proliferation, invasiveness, and migration in vitro. Conclusions: The DR-based scoring system that we developed enabled accurate prognostic stratification of LUAD patients and provides important insights into the molecular mechanisms and treatment strategies for LUAD.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Pronóstico , Adenocarcinoma del Pulmón/genética , Algoritmos , Aprendizaje Automático , Neoplasias Pulmonares/genética , Microambiente Tumoral
9.
Org Biomol Chem ; 21(16): 3317-3322, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37009653

RESUMEN

A variety of azaheterocycle-fused piperidines and pyrrolidines bearing CF3 and CHF2 functionalities were obtained using CF3SO2Na and CHF2SO2Na by visible light photocatalysis. This protocol involves a radical cascade cyclization via tandem tri- and difluoromethylation-arylation of pendent unactivated alkenes. Benzimidazole, imidazole, theophylline, purine, and indole serve as applicable anchors, thereby enriching the structural diversity of piperidine and pyrrolidine derivatives. This method features mild, additive-free and transition metal-free conditions.

10.
Sensors (Basel) ; 23(7)2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37050570

RESUMEN

Various navigation tasks involving dynamic scenarios require mobile robots to meet the requirements of a high planning success rate, fast planning, dynamic obstacle avoidance, and shortest path. PRM (probabilistic roadmap method), as one of the classical path planning methods, is characterized by simple principles, probabilistic completeness, fast planning speed, and the formation of asymptotically optimal paths, but has poor performance in dynamic obstacle avoidance. In this study, we use the idea of hierarchical planning to improve the dynamic obstacle avoidance performance of PRM by introducing D* into the network construction and planning process of PRM. To demonstrate the feasibility of the proposed method, we conducted simulation experiments using the proposed PRM-D* (probabilistic roadmap method and D*) method for maps of different complexity and compared the results with those obtained by classical methods such as SPARS2 (improving sparse roadmap spanners). The experiments demonstrate that our method is non-optimal in terms of path length but second only to graph search methods; it outperforms other methods in static planning, with an average planning time of less than 1 s, and in terms of the dynamic planning speed, our method is two orders of magnitude faster than the SPARS2 method, with a single dynamic planning time of less than 0.02 s. Finally, we deployed the proposed PRM-D* algorithm on a real vehicle for experimental validation. The experimental results show that the proposed method was able to perform the navigation task in a real-world scenario.

11.
Sensors (Basel) ; 23(5)2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36904657

RESUMEN

Ultra-fast satellite clock bias (SCB) products play an important role in real-time precise point positioning. Considering the low accuracy of ultra-fast SCB, which is unable to meet the requirements of precise point position, in this paper, we propose a sparrow search algorithm to optimize the extreme learning machine (SSA-ELM) algorithm in order to improve the performance of SCB prediction in the Beidou satellite navigation system (BDS). By using the sparrow search algorithm's strong global search and fast convergence ability, we further improve the prediction accuracy of SCB of the extreme learning machine. This study uses ultra-fast SCB data from the international GNSS monitoring assessment system (iGMAS) to perform experiments. First, the second difference method is used to evaluate the accuracy and stability of the used data, demonstrating that the accuracy between observed data (ISUO) and predicted data (ISUP) of the ultra-fast clock (ISU) products is optimal. Moreover, the accuracy and stability of the new rubidium (Rb-II) clock and hydrogen (PHM) clock onboard BDS-3 are superior to those of BDS-2, and the choice of different reference clocks affects the accuracy of SCB. Then, SSA-ELM, quadratic polynomial (QP), and a grey model (GM) are used for SCB prediction, and the results are compared with ISUP data. The results show that when predicting 3 and 6 h based on 12 h of SCB data, the SSA-ELM model improves the prediction model by ~60.42%, 5.46%, and 57.59% and 72.27%, 44.65%, and 62.96% as compared with the ISUP, QP, and GM models, respectively. When predicting 6 h based on 12 h of SCB data, the SSA-ELM model improves the prediction model by ~53.16% and 52.09% and by 40.66% and 46.38% compared to the QP and GM models, respectively. Finally, multiday data are used for 6 h SCB prediction. The results show that the SSA-ELM model improves the prediction model by more than 25% compared to the ISUP, QP, and GM models. In addition, the prediction accuracy of the BDS-3 satellite is better than that of the BDS-2 satellite.

12.
Food Funct ; 14(2): 934-945, 2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36541083

RESUMEN

Backgrounds: Doxorubicin (Dox) is a classical antitumor antibiotic widely restricted for use due to its cardiotoxicity. Daidzein (Daid) is a soy isoflavone that enhances antioxidant enzyme systems and inhibits apoptosis to prevent cardiovascular diseases. In this study, we intended to assess whether Daid protects against Dox-induced cardiotoxicity and explored its underlying mechanisms. Methods: Male Sprague-Dawley (SD) rats were divided into five groups: control (Ctrl), 40 mg per kg per day Daidzein (Daid), 3 mg per kg per week doxorubicin (Dox), 20 mg per kg per day Daidzein + 3 mg per kg per week doxorubicin (Daid20 + Dox) and 40 mg per kg per day Daidzein + 3 mg per kg per week doxorubicin (Daid40 + Dox) groups. Cardiac function assessments, immunohistochemistry (IHC) and immunofluorescence (IF) analyses were initially performed in each group of rats. Secondly, the cell proliferative capacity analysis, AO staining, and LC3 puncta analysis were employed to evaluate the cellular response to Dox in H9c2 cells. Ultimately, the protein expressions of cleaved caspase3, LC3 II, Bcl-2, Bax, Akt, p-Akt, and cyclin D1 were examined by western blotting. Results: Pretreatment with a low dose of Daid rather than a high dose significantly enhanced cardiac function and alleviated histopathological deterioration of cardiomyocytes induced by Dox. Daid downregulated the protein levels of Bax, LC3 II, cleaved caspase3 and p-Akt, while up-regulating Bcl-2 and cyclin D1. The Akt agonist SC79 could invalidate all the protective effects of Daid both in vivo and in vitro. Conclusions: Daid reduced autophagy and apoptosis by inhibiting the PI3K/Akt pathway, thereby protecting the hearts from Dox-induced cardiac damage.


Asunto(s)
Ciclina D1 , Isoflavonas , Ratas , Masculino , Animales , Ciclina D1/metabolismo , Cardiotoxicidad/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas Sprague-Dawley , Proteína X Asociada a bcl-2/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal , Línea Celular , Doxorrubicina , Miocitos Cardíacos , Apoptosis , Isoflavonas/farmacología , Autofagia , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Estrés Oxidativo
13.
Biosci Rep ; 43(1)2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36541246

RESUMEN

Hypoxic-ischemic brain injury contributes to major neurodevelopmental disorders and is one of the leading causes of seizures, which substantially results in neurodevelopmental impairments with long-lasting outcomes and is one of the main causes of death in neonates. We aimed to investigate the correlation between miRNA-210 and SCN1B, a voltage-gated sodium channel gene, in brain tissue of fetal rats with hypoxic-ischemic brain injury. We found that after 10 min of hypoxia-ischemia, all reperfusion groups showed different degrees of damage. The degree of the injury increased in all the groups after 30 min of hypoxia-ischemia. Those changes include changes in the pericellular lumen, capillaries in the cortex, erythrocytes, enlarged pericellular lumen, the enlarged pericapillary lumen in the cortex, edema around glial cells, enlarged gap to form multiple necrotic foci, deformation of neurons, and loss of cell structure. The expression levels of HIF-1α, miRNA-210, and HIF-1α mRNA were higher in the hypoxic-ischemic groups than that in the control groups, among which the expression levels in the severe group were higher than that in mild group. SCN1B is down-regulated in both the mild and severe groups, and the lowest level was found at 30 min after hypoxia in both groups. MiRNA-210 plays a role in the development of hypoxic-ischemic encephalopathy (HIE) by regulating the expression changes of SCN1B. The brain tissue of fetal rats in the hypoxic-ischemic animal model showed pathological changes of brain injury.


Asunto(s)
Lesiones Encefálicas , Hipoxia-Isquemia Encefálica , MicroARNs , Animales , Ratas , Hipoxia-Isquemia Encefálica/genética , Encéfalo/patología , Neuronas/metabolismo , Lesiones Encefálicas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo
14.
Chem Sci ; 13(44): 13117-13121, 2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36425490

RESUMEN

An unprecedented copper-catalyzed four-component reaction of arylcyclopropanes, nitriles, carboxylic acids and N-fluorobenzenesulfonimide (NFSI) has been successfully developed, which represents the first example of a four-component reaction of non-donor-acceptor cyclopropanes. A wide range of imide derivatives were efficiently synthesized in excellent yields under mild conditions.

15.
Molecules ; 27(18)2022 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-36144712

RESUMEN

An improved method to efficiently synthesize 2-OH thioaryl glycosides starting from corresponding per-protected glycals was developed, where 1,2-anhydro sugars were prepared by the oxidation of glycals with oxone, followed by reaction of crude crystalline 1,2-anhydro sugars with NaBH4 and aryl disulfides. This method has been further used in a one-pot reaction to synthesize glycosyl donors having both "armed" and "NGP (neighboring group participation)" effects.


Asunto(s)
Tioglicósidos , Disulfuros , Glicósidos/química , Glicosilación , Azúcares , Tioglicósidos/química
16.
Micromachines (Basel) ; 13(9)2022 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-36144040

RESUMEN

Effective cooling of a high heat flux IGBT electronic system is highly related to system efficiency and safety. A flat plate heat sink was designed to experimentally investigate the transient heat transfer characteristics of IGBT cooling. It is made of aluminum with 20 mini-channels of 249 mm × 3 mm × 4 mm dimensions, which were manufactured by milling machines and melt inert gas (MIG) welding technology to ensure no deformation. Experiments were conducted using deionized water at atmospheric pressure with flow rates of 3.2-9.5 L/min and heat fluxes of 104-347 W/cm2. It was found that instantaneous start-stop and transient heating power variation might cause IGBT failure, especially under low Reynolds and Nusselt number conditions. The temperature rise rate and cooling rate vary with different system parameters. Heating rate can be reduced by high flow rate due to local subcooled boiling. The concept of respond time (RT) based on the piecewise function is suggested to evaluate the influence of transient condition on heating rate. Analysis of flow fluctuation indicated that it would not be a threat to the system except for in extreme cases. These findings provide a reference for the considerations of the design and manufacture of IGBT cooling flat plate heat sinks with mini-channels.

17.
Front Oncol ; 12: 947810, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35912235

RESUMEN

Background: Endoscopic forceps biopsy (EFB) lacks precision in diagnosing indeterminate tumors. When the presence of early gastric cancer (EGC) is macroscopically suspected, but biopsy pathology fails to give a diagnosis of neoplasia, it causes problems in clinical management. The purpose of this study was to discuss the outcome of gastric indeterminate tumors and the clinical factors associated with predicting EGC. Methods: The medical records of 209 patients diagnosed with gastric indeterminate neoplasia by biopsy forceps were retrospectively studied. Initial endoscopic findings were analyzed and predictors of EGC were evaluated. Results: The final pathological diagnosis in 209 patients included adenocarcinoma (n = 7), high-grade intraepithelial neoplasia (n = 11), low-grade intraepithelial neoplasia (n = 21), and non-neoplastic lesion (n = 170). Multivariate analysis showed that older age (OR = 1.78; 95% CI = 1.17-2.71; p = 0.008), patients undergoing narrow band imaging (NBI) (OR = 3.40; 95% CI = 1.37-8.43; p = 0.008), and surface erosion (OR = 3.53; 95% CI = 1.41-8.84; p = 0.007) were associated with the upgraded group, and were significantly associated with risk. Univariate logistic regression analysis showed that among patients with NBI, the presence of demarcation line (DL) (OR = 24.00; 95% CI = 4.99-115.36; p < 0.0001), microvascular (MV) pattern irregularity (OR = 9.129; 95% CI = 2.36-35.34; p = 0.001), and the presence of white opaque substance (WOS) (OR = 10.77; 95% CI = 1.14-101.72; p = 0.038) were significant risk factors. Conclusions: For gastric indeterminate tumors, older patient age, lesion surface with erosion, clear DL visible under NBI observation, presence of WOS, and irregular MV pattern are suggestive of the high possibility of neoplasia and need to be focused on and may benefit more from endoscopic resection treatment as opposed to simple endoscopic follow-up.

18.
Chem Sci ; 13(26): 7886-7891, 2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35865909

RESUMEN

Cyclobutenes as versatile and highly valuable synthons have been widely applied in synthesis. Although various methods for their synthesis have been well established, new strategies for the construction of the cyclobutene skeleton from simple substrates are still highly desirable. Starting from simple cyclobutanes, the construction of the cyclobutene skeleton especially introducing multiple functional groups simultaneously had never been achieved. Here, we developed a novel radical cascade strategy for the synthesis of highly functionalized cyclobutenes directly from cyclobutanes involving rare cleavage of four or five C-H bonds and formation of two C-N/C-S or three C-Br bonds. With copper as catalyst and N-fluorobenzenesulfonimide (NFSI) as oxidant, a wide range of diaminated, disulfonylated and tribrominated cyclobutene derivatives were efficiently synthesized.

19.
Small ; 18(34): e2203236, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35858243

RESUMEN

Aluminum is the most abundant metal element in the Earth's crust, thus developing the rechargeable aluminum-ion batteries (AIBs) provides an ideal opportunity to realize cells with pleasing energy-to-price ratios. However, the further development of AIBs is plagued by the scarcity of suitable positive electrode materials. Here, for the first time, a tin-based alloy positive electrode material for AIBs, Co3 Sn2 wrapped with graphene oxide (Co3 Sn2 @GO composite) is well-designed and investigated to understand the aluminum storage behavior. A series of experimental measurements and theoretical calculations results reveal that a novel "bimetallic activated center alloying reaction" aluminum storage mechanism is occurred on the prepared Co3 Sn2 positive electrode. The reversible alloying/de-alloying process in AlCl3 /[EMIm]Cl ionic liquid, where both Co and Sn in Co3 Sn2 alloys react electrochemically with Al3+ to form Alx Sn and Aly Co is first put forward. This study delineates new insights on the aluminum storage mechanism, which may guide to ultimately exploit the energy benefits of "bimetallic activated center alloying redox".

20.
Front Public Health ; 10: 885624, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35685764

RESUMEN

Background: Pancreatic cancer (PC) is a highly malignant tumor of the digestive system. The number of elderly patients with PC is increasing, and older age is related to a worse prognosis. Accurate prognostication is crucial in treatment decisions made for people diagnosed with PC. However, an accurate predictive model for the prognosis of these patients is still lacking. We aimed to construct nomograms for predicting the overall survival (OS) of elderly patients with PC. Methods: Patients with PC, older than 65 years old from 2010 to 2015 in the Surveillance, Epidemiology, and End Results database, were selected and randomly divided into training cohort (n = 4,586) and validation cohort (n = 1,966). Data of patients in 2016-2018 (n = 1,761) were used for external validation. Univariable and forward stepwise multivariable Cox analysis was used to determine the independent prognostic factors. We used significant variables in the training set to construct nomograms predicting prognosis. The performance of the models was evaluated for their discrimination and calibration power based on the concordance index (C-index), calibration curve, and the decision curve analysis (DCA). Results: Age, insurance, grade, surgery, radiation, chemotherapy, T, N, and American Joint Commission on Cancer were independent predictors for OS and thus were included in our nomogram. In the training cohort and validation cohort, the C-indices of our nomogram were 0.725 (95%CI: 0.715-0.735) and 0.711 (95%CI: 0.695-0.727), respectively. The 1-, 3-, and 5-year areas under receiver operating characteristic curves showed similar results. The calibration curves showed a high consensus between observations and predictions. In the external validation cohort, C-index (0.797, 95%CI: 0.778-0.816) and calibration curves also revealed high consistency between observations and predictions. The nomogram-related DCA curves showed better clinical utility compared to tumor-node-metastasis staging. In addition, we have developed an online prediction tool for OS. Conclusions: A web-based prediction model for OS in elderly patients with PC was constructed and validated, which may be useful for prognostic assessment, treatment strategy selection, and follow-up management of these patients.


Asunto(s)
Nomogramas , Neoplasias Pancreáticas , Factores de Edad , Anciano , Humanos , Neoplasias Pancreáticas/terapia , Modelos de Riesgos Proporcionales , Programa de VERF , Estados Unidos/epidemiología , Neoplasias Pancreáticas
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