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1.
Inorg Chem ; 62(33): 13328-13337, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37556609

RESUMO

It is a challenging task to utilize efficient electrocatalytic metal hydroxide-based materials for the oxygen evolution reaction (OER) in order to produce clean hydrogen energy through water splitting, primarily due to the restricted availability of active sites and the undesirably high adsorption energies of oxygenated species. To address these challenges simultaneously, we intentionally engineer a hollow star-shaped Ag/CoMo-LDH heterostructure as a highly efficient electrocatalytic system. This design incorporates a considerable number of heterointerfaces between evenly dispersed Ag nanoparticles and CoMo-LDH nanosheets. The heterojunction materials have been prepared using self-assembly, in situ transformation, and spontaneous redox processes. The nanosheet-integrated hollow architecture can prevent active entities from agglomeration and facilitate mass transportation, enabling the constant exposure of active sites. Specifically, the powerful electronic interaction within the heterojunction can successfully regulate the Co3+/Co2+ ratio and the d-band center, resulting in rational optimization of the adsorption and desorption of the intermediates on the site. Benefiting from its well-defined multifunctional structures, the Ag0.4/CoMo-LDH with optimal Ag loading exhibits impressive OER activity, the overpotential being 290 mV to reach a 10 mA cm-2 current density. The present study sheds some new insights into the electron structure modulation of hollow heterostructures toward rationally designing electrocatalytic materials for the OER.

2.
Huan Jing Ke Xue ; 45(5): 2952-2961, 2024 May 08.
Artigo em Zh | MEDLINE | ID: mdl-38629556

RESUMO

To explore the pollution characteristics and source of soil heavy metal in a coal mine area near the Yellow River in Shandong, the geo-accumulation index method and improved Nemerow pollution index method were used to evaluate the pollution characteristics of soil heavy metal. The absolute principal component-multiple linear regression model (APCS-MLR) was used to quantitatively analyze the source of soil heavy metal, and the spatial distribution of Hg and Cd were analyzed using the Kriging spatial difference method in ArcGIS. The result accuracy of the APCS-MLR model was further verified. The results showed that:The measured contents of soil heavy metal Cu, Zn, Pb, Cr, Cd, Ni, As, and Hg all exceeded the normal site, among which, Hg and Cd exceeded the background values of soil elements in Shandong. The coefficient of variation (CV) of Hg was higher than 0.500, indicating significant spatial heterogeneity. Moreover, the correlation between Hg and other heavy metals was generally low, and the possibility of the same pollution source was small. The results of the geo-accumulation index and improved Nemerow pollution index showed that the overall soil heavy metal pollution was at a moderate level, among which the Hg pollution level was the highest, and its maximum value was at a slanted-heavy pollution level; Cu, Cd, and As in soil caused local pollution, which were at a slanted-light pollution level. Soil heavy metal pollution was closely related to mining activities, rehabilitation, and engineering construction in the coal mine area. The two major pollution sources of soil heavy metal in the research area were the compound source of the parent material and industrial and mining transportation sources (known source 1) and the compound source of atmospheric sedimentation and coal production (known source 2), the contribution rates of which were 76.705% and 16.171%, respectively. The results of the APCS-MLR model were shown to be reliable by analyzing the content distribution of Hg and Cd using the Kriging space difference mode. This research can provide scientific basis for the precise control and improvement of soil heavy metal pollution, ensuring the safety of food and agricultural products and improving the quality of the ecological environment in the coal mine area in the Shandong section of the Yellow River Basin.

3.
Artigo em Inglês | MEDLINE | ID: mdl-39356200

RESUMO

High-/medium-entropy materials have been explored as promising electrocatalysts for water splitting due to their unique physical and chemical properties. Unfortunately, state-of-the-art materials face the dilemma of explaining the enhancement mechanism, which is now limited to theoretical models or an unclear cocktail effect. Herein, a medium-entropy NiCoFeMnP with an advanced hierarchical particle-nanosheet-tumbleweed nanostructure has been synthesized via simple precursor preparation and subsequent phosphorization. Evaluated as the electrocatalyst for oxygen evolution reaction (OER), the medium-entropy NiCoFeMnP displays a lower overpotential of 272 mV at a current density of 10 mA cm-2, and more favorable kinetics than the binary NiFeP, ternary NiCoFeP, quaternary NiCoFeCuP and NiCoFeCrP counterparts, and other reported high-/medium-entropy electrocatalysts. Careful experimental analyses reveal that the incorporation of Mn can significantly regulate the electronic structure of Ni, Co, and Fe sites. More importantly, the Mn introduction and entropy stabilization effect in the reconstructed metal (oxy)hydroxide simultaneously promote the lattice oxygen mechanism, improving the activity. This work sheds new light on the design of high-/medium-entropy materials from an in-depth understanding of the underlying mechanism for improving energy conversion efficiency.

4.
Materials (Basel) ; 15(3)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35160641

RESUMO

Friction stir lap welding (FSLW) is expected to join the hybrid structure of aluminum alloy and steel. In this study, the Al-Mg-Si aluminum alloy and 301L stainless steel were diffusion bonded by FSLDW with the addition of 0.1 mm thick pure Zn interlayer, when the tool pin did not penetrate the upper aluminum sheet. The characteristics of lap interface and mechanical properties of the joint were analyzed. Under the addition of Zn interlayer, the diffusion layer structure at lap interface changed from continuous to uneven and segmented. The components of the diffusion layer were more complex, including Fe-Al intermetallic compounds (IMCs), Fe-Zn IMCs and Al-Zn eutectic. The largely changed composition and thickness of uneven and segmented diffusion layer at the lap interface played a significant role in the joint strength. The tensile shear load of Zn-added joint was 6.26 kN, increasing by 41.3% than that of Zn-not-added joint. These two joints exhibited interfacial shear fracture, while the Zn interlayer enhanced the strength of diffusion bonding by extending the propagation path of cracks.

5.
Gland Surg ; 10(12): 3342-3350, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35070894

RESUMO

BACKGROUND: Thymectomy has been identified as an effective strategy for patients with myasthenia gravis (MG) and thymic masses. However, the best surgical approach remains a matter of debate. The aim of the present study was to compare the surgical and neurological outcomes of video-assisted thoracoscopic thymectomy with a modified subxiphoid and bilateral approach in patients with MG and thymic masses. METHODS: From August 2013 to April 2018, 68 patients who were diagnosed with MG and thymic masses and underwent video-assisted thoracoscopic thymectomy with a modified subxiphoid (44 patients) or bilateral (24 patients) approach were included in this retrospective study. The surgical and neurological results were analyzed with propensity score matching. RESULTS: After propensity score matching, the modified subxiphoid approach in video-assisted thoracoscopic thymectomy resulted in an obviously shorter operative time (P=0.00), drainage duration (P=0.00), less intraoperative blood loss (P=0.00), and shorter postoperative hospital stay (P=0.01). In terms of neurological outcomes, no significant difference was observed in the improvement in MG, with 2-year complete stable remission rates of 21.1% and 26.3% (P=0.68) and 2-year pharmacological remission rates of 31.6% and 26.3% (P=0.60) for the bilateral and subxiphoid approaches, respectively. Additionally, the approaches resulted in similar effects on the magnitudes of decrease in the prednisolone and pyridostigmine doses after 2 years, with average pyridostigmine dose reductions of 72.2% and 71.1% (P=0.78) and average prednisolone reductions of 76.8% and 71.7% (P=0.96) for the bilateral and subxiphoid approaches, respectively. CONCLUSIONS: The modified subxiphoid approach was found to be superior to the bilateral approach in video-assisted thoracic surgery thymectomy in terms of the surgical outcomes and yielded similar neurological outcomes. Therefore, the modified subxiphoid approach is recommended as an alternative to the bilateral approach in the treatment of patients with MG and thymic masses.

6.
Chin Med J (Engl) ; 132(14): 1666-1672, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31268911

RESUMO

BACKGROUND: The detection of polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes (POEMS) syndrome at early stage is challenging for neurologists. Since polyneuropathy could be the first manifestation, it could be misdiagnosed as chronic inflammatory demyelinating polyneuropathy (CIDP). The present study aimed to determine the clinical and electrophysiological features of POEMS syndrome to distinguish from CIDP. METHODS: The data of a group of patients with POEMS (n = 17) and patients with CIDP (n = 17) in Zhongshan Hospital Fudan University from January 2015 to September 2017 were analyzed in this retrospective study. The clinical features, neurological symptoms, and electrophysiological findings were compared between the two groups. RESULTS: Clinically, patients with POEMS demonstrated significantly more neuropathic pain in the lower extremities than patients with CIDP (58.8% vs. 11.8%, P = 0.01). Multisystem features like edema, skin change, organomegaly, and thrombocytosis were also pointed towards the diagnosis of POEMS syndrome. Electrophysiologically, terminal latency index (TLI) was significantly higher in patients with POEMS than that in patients with CIDP (median nerve: 0.39 [0.17-0.52] vs. 0.30 (0.07-0.69), Z = -2.413, P = 0.016; ulnar nerve: 0.55 [0.23-0.78] vs. 0.42 [0.12-0.70], Z = -2.034, P = 0.042). Patients with POEMS demonstrated a higher frequency of absent compound muscle action potential of the tibial nerve (52.9% vs. 17.6%, P = 0.031), less conduction block (ulnar nerve: 0 vs. 35.3%, P = 0.018), and less temporal dispersion (median nerve: 17.6% vs. 58.8%, P = 0.032) than CIDP group. The combination of positive serum monoclonal protein and high TLI (if either one or both were present) discriminated POEMS from CIDP with a sensitivity of 94.1% and 47.1% and specificity of 76.5% and 100.0%, respectively. CONCLUSIONS: POEMS syndrome could be distinguished from CIDP through typical clinical and electrophysiological characteristics in practice. The combination of serum monoclonal protein and high TLI might raise the sensitivity of detecting POEMS syndrome.


Assuntos
Síndrome POEMS/diagnóstico , Polineuropatias/diagnóstico , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico , Idoso , Eletrofisiologia , Feminino , Humanos , Masculino , Nervo Mediano/fisiologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Anormalidades da Pele/diagnóstico , Nervo Ulnar/fisiologia
7.
Zhonghua Bing Li Xue Za Zhi ; 36(11): 760-3, 2007 Nov.
Artigo em Zh | MEDLINE | ID: mdl-18307882

RESUMO

OBJECTIVE: Tumor dormancy has been defined clinically as a condition in which tumor cells are present but do not grow for a long period of time. Breast cancer is noted for its long periods of tumor dormancy and metastases can occur many years after treatment. METHOD: Simulating the characteristics of breast cancer patients after treatment, we established the animal model of breast cancer dormancy by inoculating 500 Ca761-03 cells into the limb muscle of 615 mice and then selecting animals with tumor dormancy 2 months post inoculation (corresponding to 5 years for humans). RESULTS: Two months after inoculation of Ca761-03 cells into the muscle of 615 mice, tumor occurred in 30% of the mice. The remaining 70% of mice did not show tumor growth. After repeated traumatic stimulation, 90% of the mice developed tumors after 5 months, therefore representing tumor dormancy. CONCLUSIONS: These results demonstrate that breast cancer cells can remain in a dormant state for long periods of time in vivo. Trauma can stimulate the dormant tumor cells to proliferate again, and causes tumor relapse. This murine model system promises a sound animal model for the study of solid tumor dormancy.


Assuntos
Neoplasias da Mama/fisiopatologia , Modelos Animais de Doenças , Neoplasias do Colo do Útero/fisiopatologia , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Progressão da Doença , Feminino , Humanos , Masculino , Camundongos , Recidiva Local de Neoplasia , Transplante de Neoplasias , Distribuição Aleatória , Neoplasias do Colo do Útero/patologia
8.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 29(3): 353-8, 2007 Jun.
Artigo em Zh | MEDLINE | ID: mdl-17633461

RESUMO

OBJECTIVE: To evaluate the effect of combination of eicosapentaenoic acid (EPA) and The effects of EPA and epirubicin (EPI) on the human gastric carcinoma cell MGC-803 in vitro. METHODS: EPI were measured by MTT assay , and the interaction between these two agents was evaluated by the isobologram technique of Berenbaum. Morphous of cell was observed by phase-contrast and electron microscope. Flow cytometry was used for cell cycle analysis. RESULTS: EPA significantly inhibited the growth of MGC-803 cells in a dose- and time-dependent way (P < 0.01). Numerous abnormal particles were found around the nucleus of MGC-803 cells under phase-contrast microscope, and also many electron-dense material in cytoplasm were found under electron microscope. EPA significantly stimulated the growth of human embryonal pulmonary fibroblast (HPF) dose-dependently (P < 0.01). A strong synergism was found between EPA and EPI in MGC-803 cells. EPA induced G0/G1-phase arrest but without statistical significance (P > 0.05), and EPI significantly induced S-phase arrest (P < 0.05) in MGC-803 cells. CONCLUSIONS: EPA can inhibit cell growth in gastric carcinoma cells but not in normal cells. EPA and EPI have synergetic effect in the inhibition of gastric carcinoma cells. Compared with EPI monotherapy, the combination of EPI and EPA can reduce the dosage of EPI.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ácidos Araquidônicos/administração & dosagem , Linhagem Celular Tumoral , Sinergismo Farmacológico , Epirubicina/administração & dosagem , Humanos
9.
Zhong Xi Yi Jie He Xue Bao ; 4(5): 495-9, 2006 Sep.
Artigo em Zh | MEDLINE | ID: mdl-16965744

RESUMO

OBJECTIVE: To observe the effects of Jianpi Yishen Recipe (JPYSR), a compound Chinese herbal medicine, on recurrence, metastasis and life span of mice transplanted with proventriculus squamous carcinoma cells after tumorectomy. METHODS: JPYSR was orally administered to 615 mice transplanted with proventriculus squamous carcinoma cells in the palma of left hind limb after tumorectomy. The local tumor recurrence, lung metastasis and life span of the mice were evaluated and compared with those of the 5-FU-treated mice and untreated mice. RESULTS: The pulmonary metastasis rate was 94.4% and the recurrence rate was 94.44% in untreated group. The pulmonary metastasis rate was 68.4%, the inhibition rate of pulmonary metastasis was 27.5%, the recurrence rate was 78.95%, and the inhibition rate of tumor recurrence was 65.35% in JPYSR-treated group. The average and median life spans were obviously prolonged in JPYSR-treated group, as compared with those in untreated group. The life-prolonging rate was 100%. CONCLUSION: JPYSR can effectively inhibit the local recurrence and pulmonary metastasis of the transplanted proventriculus squamous carcinoma in mice after tumorectomy, and prolong the life span.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Administração Oral , Animais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Medicamentos de Ervas Chinesas/administração & dosagem , Feminino , Neoplasias Pulmonares/prevenção & controle , Neoplasias Pulmonares/secundário , Masculino , Camundongos , Camundongos Endogâmicos , Recidiva Local de Neoplasia , Transplante de Neoplasias , Fitoterapia , Período Pós-Operatório , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Análise de Sobrevida
10.
Zhonghua Bing Li Xue Za Zhi ; 34(10): 661-3, 2005 Oct.
Artigo em Zh | MEDLINE | ID: mdl-16536280

RESUMO

OBJECTIVE: To establish a rabbit tumor cell line and to characterize its biological parameters. METHODS: VX2 tumor tissue was used for the primary culture in vitro. After 40 passages, the cell morphology, CK expression (immunohistochemical staining), cell cycle, karyotype and tumorigenecity in rabbits and nude mice were investigated. RESULTS: The newly established cell line VX2 was maintained in continuous culture for over 70 passages in 10 months. Morphologically, VX2 cells were polygonal to short spindled. Tonal fibril and tight junction were found under the electron microscope. CK was positive. The cell cycle analysis showed 69.3% in G1 phase, 5.6% in G2 phase and 25.1% in S phase. The population doubling time was 34.5 hours. The chromosomal analysis showed a hypotriploidy with a median chromosome number of 58 approximately 62. The tumorigenecity in rabbits and nude mice were both 100%. CONCLUSION: The established VX2 cell line derived from rabbit squamous carcinoma could serve as a model system for experimental oncology in the rabbit.


Assuntos
Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Animais , Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/ultraestrutura , Ciclo Celular , Queratinas/análise , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Poliploidia , Coelhos
11.
Eur J Med Res ; 20: 11, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25649241

RESUMO

Critical illness polyneuropathy and myopathy are multifaceted complications that follow severe illnesses involving the sensorimotor axons and proximal skeletal muscles. These syndromes have rarely been reported among renal transplant recipients. In this paper, we report a case of acute quadriplegia caused by necrotizing myopathy in a renal transplant recipient with severe pneumonia. The muscle strength in the patient's extremities improved gradually after four weeks of comprehensive treatment, and his daily life activities were normal a year after being discharged.


Assuntos
Transplante de Rim/efeitos adversos , Doenças Musculares/complicações , Pneumonia/complicações , Quadriplegia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
12.
Zhonghua Bing Li Xue Za Zhi ; 32(4): 354-9, 2003 Aug.
Artigo em Zh | MEDLINE | ID: mdl-14514383

RESUMO

OBJECTIVE: To detect whether the activation of nuclear factor-kappa B (NF-kappaB) in endothelial cells induced by mm-LDL can promote platelet-derived growth factor-B (PDGF-B) expression in vitro, and whether it is also present in hypercholesterolemic rats in vivo, influence of age on NF-kappaB and PDGF-B signal transduction pathway. METHODS: Established hypercholesterolemic rat model by feeding with a high-cholesterol ration. The activation of NF-kappaB in aortic endothelial cells was identified by immunohistochemical staining, the expression of PDGF-B mRNA and PDGF-B protein were examined using in situ hybridization and immunohistochemistry respectively. RESULTS: In comparison with the control rats, a positive immunostaining of NF-kappaB in nuclei of aortic endothelial cells of the experimental rats was detected after a high cholesterol ration for 6 weeks. The number of endothelial cells expressing PDGF-B mRNA increased and the intensity was dependent upon the duration of high-cholesterol intake. NF-kappaB translocation (0.461 +/- 0.075 vs. 0.350 +/- 0.094, P < 0.05) and PDGF-B expression in 10-month old Wistar rats were more remarkable than that of 2-month old rats after having cholesterol for 16 weeks. Immunohistochemical staining for PDGF-B gave a similar result (0.230 +/- 0.040 vs. 0.185 +/- 0.037, P < 0.001). CONCLUSIONS: Hypercholesterolemia is capable of activating nuclear translocation of NF-kappaB and promoting expression of PDGF-B in rat aortic endothelial cells in vivo, this coincided with the results obtained in ox-LDL or mm-LDL experiments on endothelial cells in vitro. This phenomenon is much more evident in 10-month old rats which indicates that age might have a close relationship with NF-kappaB - PDGF-B signal transduction pathway.


Assuntos
Células Endoteliais/metabolismo , Hipercolesterolemia/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-sis/genética , Transporte Ativo do Núcleo Celular , Fatores Etários , Animais , Aorta/metabolismo , Arteriosclerose/etiologia , Imuno-Histoquímica , Masculino , Proteínas Proto-Oncogênicas c-sis/análise , RNA Mensageiro/análise , Ratos , Ratos Wistar
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