Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Front Oncol ; 13: 1230021, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37664039

RESUMEN

Malignant rhabdoid tumors (MRTs) are rare tumors with high mortality rates and poor prognoses. MRTs occur mainly in the central nervous system, kidneys, and soft tissues, but rarely in the omentum. MRTs occur more commonly in infants and children and less frequently in adults. Here, we report the first observed case of MRT in an adult omentum. A 35-year-old man with abdominal distension and pain was admitted to the emergency department. Previously, several hospitals considered patients with cirrhosis who had not received active treatment. Computed tomography and magnetic resonance imaging revealed diffuse omental thickening and massive ascites. The surgery was performed at our hospital, and the pathological diagnosis was MRT with a SMARCB1(INI-1) deletion. Postoperatively, his symptoms improved, and he underwent five cycles of chemotherapy. However, 6 months after surgery, the tumor developed liver metastases, and the patient subsequently died. Primary MRT of the greater omentum is rare, and its pathological diagnosis usually requires extensive clinicopathological evaluation of various differential diagnoses and an appropriate work-up to exclude other malignancies associated with SMARCB1 deletion. At the same time, the lack of specific signs of omental MRT and its rapid progression should alert clinicians.

2.
J Phys Chem Lett ; 14(33): 7526-7540, 2023 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-37584649

RESUMEN

This work systematically studies the product self-catalysis of in situ electrochemical cobalt doping of Li2O2 and reveals its potential mechanism for improving the performance of lithium-oxygen (Li-O2) batteries. Theoretical calculations demonstrate that the discharge products contain substituted and interstitial Co impurities, which serve as active sites to promote the formation of Li3O4 crystallization, thus switching the nucleation mechanism from the main discharge product Li2O2 to Li3O4. This Co-doping behavior leads to the thermodynamically favorable and dynamically stable formation of Li3O4 crystals during the discharge process. Through systematic investigation of the structural, energetic, electronic, diffusive, and catalytic properties of the Co-doped Li2O2 and Li3O4 compounds, we found that Li3O4 has better charge/mass transport and a lower overpotential for the Li3O4 formation/decomposition reaction. Consequently, this work elucidates that Co doping provides a simple and effective approach for increasing the proportion of Li3O4, which can significantly improve the Li-O2 battery performance.

3.
Exp Ther Med ; 24(2): 502, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35837046

RESUMEN

Pancreatic cancer (PC) is a malignant tumor with high mortality worldwide. SIRT6 plays versatile roles in human cancers. However, SIRT6 has rarely been studied in PC. The purpose of the present study was to explore the function and potential mechanism of SIRT6 in PC. The expression of SIRT6 in PC tissues and cells was detected by reverse transcription-quantitative PCR and western blotting. The overall survival time was analyzed through the Kaplan Meier method. Cell viability was measured by the Cell Counting Kit-8 assay. The Fe2+ content, glucose uptake, lactic acid and ATP production were detected through the corresponding kits. ROS was evaluated using the DCFH-DA detection kit. Protein expression was assessed by immunohistochemistry or western blot analysis. In the present study, SIRT6 was lowly expressed in PC tissues and cells compared with normal tissues and cells. Moreover, the low expression of SIRT6 was associated with a poor prognosis in patients with PC. Upregulation of SIRT6 significantly promoted the ferroptosis and inhibited the glycolysis in PC cells. However, knockdown of SIRT6 resisted ferroptosis and increased glycolysis in PC cells. Further studies found that the activation of NF-κB could reverse the effect of SIRT6 on PC cells. In addition, overexpression of SIRT6 restrained the growth of xenografted tumors and suppressed the nuclear transcription of NF-κB in vivo. Collectively, the present study indicated that SIRT6 promoted ferroptosis and inhibited glycolysis through inactivating the NF-κB signaling pathway in PC. These findings suggested that SIRT6 may become a therapeutic target for PC.

4.
Contrast Media Mol Imaging ; 2022: 8752375, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35821889

RESUMEN

It is imperative to seize the "golden rescue time" and implement new concepts and new skills in modern trauma rescue. Combining with the development background of smart medical image analysis, this topic focuses on surgical strategies and prognostic measures and studies a serious and difficult disease frequently occurring in middle-aged and elderly people: pancreatic neuroendocrine tumors. This article uses the comparative test method and sample collection method to collect the medical records of patients with neuroendocrine tumors diagnosed by pathology from July 2010 to January 2018 in the First Affiliated Hospital of X City and analyze the samples with gender and age. At the same time, routine tumor marker examination and the location of NEN in the digestive system were performed. The distribution analysis of EUS characteristics of neuroendocrine tumor mucosa in each site was performed after operation, and the analysis of survival-related factors was performed during postoperative follow-up. The experimental data showed that among the tumor causes, WHO tumor grade (p < 0.05) and whether the surgical method was R0 resection (p < 0.05) were associated with prognosis. However, factors such as gender, age, and functional status were associated with prognosis. It has successfully completed the subject of surgical strategy and prognosis of pancreatic neuroendocrine tumors based on smart medical image analysis.


Asunto(s)
Tumores Neuroendocrinos , Neoplasias Pancreáticas , Anciano , Diagnóstico por Imagen , Humanos , Persona de Mediana Edad , Tumores Neuroendocrinos/diagnóstico por imagen , Tumores Neuroendocrinos/patología , Tumores Neuroendocrinos/cirugía , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/cirugía , Pronóstico , Estudios Retrospectivos
5.
ACS Appl Mater Interfaces ; 14(24): 27861-27872, 2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35678821

RESUMEN

The electrochemical nitrogen reduction reaction (NRR) is expected to achieve sustainable ammonia synthesis via direct nitrogen fixation; however, the high-quality catalysts that play a crucial role in the NRR are still lacking. The emerging transition metal-1,3,5-triethynylbenzene (TM-TEB) frameworks offer attractive possibilities in the electrochemical catalysis due to the featured atomic and electronic structures. This work presents a comprehensive first-principles study of the TM-TEB systems for TMs from the first three d-block series and systematically explores their potential applications as NRR electrocatalysts. By designing a hierarchical screening strategy, the TM-TEB systems are evaluated based on the NRR catalytic activity as well as the competition from the hydrogen evolution reaction. In addition, in order to have a deeper understanding of the catalytic activities of the TM-TEB systems, diverse possible NRR paths on the TM-TEB surfaces are completely analyzed as well. Our analysis reveals that the TM-TEB systems with TM = V, Mo, Tc, W, and Os are electrocatalysts with a high NRR catalytic activity, while among them, only Mo- and V-TEB show promising NRR selectively. This work demonstrates the great potential of the TM-TEB systems as electrocatalysts in the NRR process, which improves the understanding of the TM-TEB systems and can motivate further exploration of their application in catalysis.

6.
Environ Geochem Health ; 44(3): 1081-1098, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34170458

RESUMEN

A machine learning method was used to process a multiagent information database to study the spatial distribution characteristics of agglomerations of metal-related enterprises and to analyze the spatial and temporal differentiation characteristics of pollution reduction in metal-related enterprises. Based on the spatial distribution of enterprises and a simulation of their pollution reduction behaviors, the layout of 380 enterprises sample is optimized, and the direction of industrial transfer is planned to give full play to the pollution reduction effect of enterprise agglomeration. The results showed that (1) the metal-related enterprises in the Chang-Zhu-Tan urban agglomeration have obvious spatial heterogeneity and are mainly distributed in the district of Changsha, the Qingshuitang Industrial Zone, Liling city and the Qibaoshan Industrial Zone of Liuyang city, while the metal-related enterprises in Shaoshan city, Zhuzhou County and Liling city are scattered. (2) The pollution emission behaviors of enterprises differ in time and space, and the pollution concentrations are highest in industrial parks such as Qingshuitang and Zhubu Port. (3) There is an interactive relationship between the degree of enterprise agglomeration and the pollution reduction effect. The spatial positive coupling degree between the concentration of metal-related enterprises and the degree of metal-related pollution is significant, accounting for 94.96% of the study area. Low pollution-high agglomeration areas, high pollution-low agglomeration areas, high pollution-high agglomeration areas, and low pollution-low agglomeration area account for 1.01%, 4.03%, 2.87%, and 92.09% of the study area, respectively. Finally, based on the new development concept of dual circulation and the theory of a two-oriented society in the new era, the paper puts forward suggestions and policies for the sustainable development of industrial transfer.


Asunto(s)
Contaminación Ambiental , Industrias , China , Ciudades , Metales , Desarrollo Sostenible
7.
Phys Chem Chem Phys ; 23(5): 3588-3594, 2021 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-33522522

RESUMEN

The thermodynamics of phosphorus (P) doping to spinel Co3O4, for both bulk cases and (100) and (110) surface cases, is studied using first principles calculations. The doping energies of the P atom at different doping sites are carefully calculated and compared. It is shown that P doping at Co sites, at either tetrahedral or octahedral sites, is energetically favorable, while P doping and replacing O atoms are energetically unfavorable. The doping energy difference is large enough to conclude that P doping has a very strong preference to take the Co sites, rather than the O sites in spinel Co3O4. Even when O-vacancy is available, P doping and taking the O-vacancy site is thermodynamically unfavorable. The physical/chemical mechanism behind this phenomenon is carefully analyzed. Electronic structure analysis shows that P doping and replacing the Co atom brings excess electrons to the Co3O4 system, which is beneficial to enhance the electrochemical and catalytic performance of the spinel Co3O4. Our results clarified the misleading results of P doping and replacing O atoms in spinel Co3O4 reported in the literature.

8.
Phys Chem Chem Phys ; 21(42): 23485-23491, 2019 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-31616886

RESUMEN

The stable sp2-C atoms in graphite enable its excellent structural and electrochemical stability as an anode material for Li-ion battery applications, while the limited Li-storage capacity of graphite also originates from the sp2 hybridization. Herein, from first-principles calculations, we show that a synergistic effect of sp2 and sp3 hybridized C atoms can substantially enhance the Li-storage performance in carbon-based anodes, using bct-C40 as an example, which is constructed with interconnected graphene layers (sp2 hybridized C atoms) and the connecting points are composed of sp3-C atoms. Charge transfer from sp2-C atoms to sp3-C atoms has been found, leading to unoccupied electronic states forming around the Fermi level. Furthermore, we found that the unoccupied electronic states are contributed by the pz orbital of the sp2-C atoms, resulting in stronger interactions between C atoms and intercalated Li atoms. As a result, the Li intercalation concentration in bct-C40 can reach as high as LiC2.5 (corresponding to a capacity of 893 mA h g-1), much higher than that of LiC6 in graphite (372 mA h g-1). Furthermore, bct-C40 inherits good structural and electrochemical stability, a metallic electronic structure, and low Li-ion migration energy barriers (0.067-0.112 eV) from the sp2 hybridized graphene structures, therefore very good Li-storage performance is expected, indicating that bct-C40 can be used as a high-performance anode material for lithium ion batteries. Our study provides new insights into the functionality of sp2- and sp3-C atoms in carbon-based anode materials and is helpful for the designing of new carbon-based anodes.

9.
Phys Chem Chem Phys ; 21(13): 7053-7060, 2019 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-30874256

RESUMEN

Two dimensional (2D) materials have great potential for application in energy storage due to their unique structural characteristics. Here we propose for the first time a density functional theory study into the scientific feasibility of using g-Mg3N2, which is a novel graphene-like 2D material, as a high-capacity anode material for Li-ion batteries (LIBs). The favorable Li-adsorption geometries and the Li adsorption thermodynamics are explored in detail. It is found that monolayer g-Mg3N2 can be lithiated up to Li7Mg3N2 that offers a super high theoretical capacity of 1858 mA h g-1 and the average intercalation potential ranging from 0.2 to 0.7 V is suitable for anode applications. The metallic electronic structures of LixMg3N2, in combination with the low Li-ion diffusion energy barriers on the honeycomb structure, promote high electron and Li-ion conductivity to ensure fast charge/discharge cycling. The excellent structural stability of Mg3N2 is good for the cycling performance. These results predict that g-Mg3N2 can serve as a high-performance anode material for LIBs.

10.
RSC Adv ; 9(47): 27378-27385, 2019 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-35529228

RESUMEN

Searching for electrode materials for non-lithium metal ion batteries (NLMIBs) is key to the success of NLMIBs. In this work, we investigated the scientific feasibility of using g-Mg3N2, which is a novel 2D graphene-like material, as an anode for non-lithium metal-ions (Na, K, Mg, Ca and Al) batteries based on density functional theory calculations. The sequential adsorption energy, Bader charge, intercalation voltage, energy-storage capacity, electronic conductivity and metal-ion diffusion energy barrier are calculated. Results show that the metal-ion intercalation potentials and diffusion energy barriers are suitable for battery application. The maximum specific capacities for Na-, K-, Mg-, Ca- and Al-ion on g-Mg3N2 are predicted to be 797, 797, 531, 1594 and 797 mA h g-1, respectively. The excellent structural stability of g-Mg3N2 is good for the cycling performance. Moreover, the electronic structure of the g-Mg3N2 changes from semiconductor to metal upon metal-ion adsorption, as well as relatively low metal-ion diffusion energy barriers (except for Al-ion diffusion), are beneficial to the charge/discharge rate of the g-Mg3N2 anode.

11.
Int Urol Nephrol ; 46(8): 1469-76, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24677000

RESUMEN

PURPOSE: In this research, the normal anatomy of urethral sphincter complex in young Chinese males has been studied. METHODS: The sagittal, coronal, and axial T2-weighted non-fat suppressed fast spin-echo images of pelvic cavities of 86 Chinese young males were studied. RESULT: Urethral sphincter complex is a cylindrical structure surrounding the urethra and extending vertically from bladder neck to perineal membrane. Urethral striated sphincter covers the anteriolateral urethra like a hat from bladder neck to verumontanum, while it surrounds the urethra in a ring shape from verumontanum to perineal membrane and backwards ends in central tendon of the perineum. From bladder neck to perineal membrane, the thickness of urethral smooth sphincter decreases gradually, and it extends forward to surround urethra with urethral striated sphincter as a ring. The length of urethral striated sphincter is 12.26-20.94 mm (mean 16.59 mm) at membranous urethra: 27.88-30.69 mm (mean 28.99 mm) from verumontanum to perineal membrane. The thickness of striated sphincter at membranous urethra is 4.29-6.86 mm (mean 5.56 mm) for the muscle of the anterior wall and 2.18-2.34 mm (mean 2.26 mm) for the muscle of the posterior wall. CONCLUSIONS: In this paper, we summarized the normal anatomy of urethral sphincter complex in young Chinese males with no urinary control problems.


Asunto(s)
Imagen por Resonancia Magnética , Uretra/anatomía & histología , Adulto , China , Humanos , Masculino , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA