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1.
BMJ Open Diabetes Res Care ; 12(1)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216296

RESUMO

INTRODUCTION: Diabetic foot ulcer (DFU) is a disabling complication of diabetes mellitus. Here, we attempted to assess whether long-term intrafemoral artery infusion of low-dose urokinase therapy improved DFUs and decreased cardiovascular events in patients with DFUs. RESEARCH DESIGN AND METHODS: This trial was a single-center, randomized, parallel study. A total of 195 patients with DFU were randomized to continuous intrafemoral thrombolysis or conventional therapy groups. The continuous intrafemoral thrombolysis group received continuous intrafemoral urokinase injection for 7 days, and conventional therapy just received wound debridement and dressing change. Then, a follow-up of average 6.5 years was performed. RESULTS: Compared with conventional therapy, at the first 1 month of intervention stage, the ulcers achieved a significant improvement in continuous intrafemoral thrombolysis group including a complete closure (72.4% vs 17.5%), an improved ulcer (27.6% vs 25.8%), unchanged or impaired ulcer (0% vs 56.7%). During the 6.5-year follow-up, for the primary outcome of ulcer closure rate, continuous intrafemoral thrombolysis therapy obtained a better complete healing rate (HR 3.42 (95% CI 2.35 to 4.98, p<0.0001)). For the secondary outcome of cardiovascular disease events, continuous intrafemoral thrombolysis therapy had a lower incidence of cardiovascular events (HR 0.50 (95% CI 0.34 to 0.74, p<0.0001)). Importantly, intrafemoral thrombolysis therapy decreased the incidence of cardiovascular death (HR 0.42 (95%CI 0.20 to 0.89, p=0.0241)). Additionally, continuous intrafemoral thrombolysis therapy improved local skin oxygenation and peripheral neuropathy as well as glycolipid metabolic profiles when compared with conventional therapy group (p<0.05). CONCLUSIONS: Continuous intrafemoral thrombolysis therapy has a better therapeutic efficacy to improve DFUs and decrease cardiovascular events. TRIAL REGISTRATION NUMBER: NCT01108120.


Assuntos
Diabetes Mellitus , Pé Diabético , Humanos , Pé Diabético/tratamento farmacológico , Seguimentos , Ativador de Plasminogênio Tipo Uroquinase/uso terapêutico , Cicatrização , Artérias
2.
Arterioscler Thromb Vasc Biol ; 43(11): e443-e467, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37767706

RESUMO

BACKGROUND: Inflammation contributes to the pathogenesis of atherosclerosis. But little is known about the potential benefits of inflammatory cells to atherosclerosis. The aim of this study was to investigate the function of inflammatory cells/endothelium axis and determine whether and how inflammatory cell-derived MYDGF (myeloid-derived growth factor) inhibited endothelial LDL (low-density lipoprotein) transcytosis. METHODS: In in vivo experiments, both loss- and gain-of-function strategies were used to evaluate the effect of inflammatory cell-derived MYDGF on LDL transcytosis. We generated monocyte/macrophage-targeted MYDGF-null mice on an Ldlr (LDL receptor)-/- background in the loss-of-function strategy and restored the inflammatory cell-derived MYDGF by bone marrow transplantation and inflammatory cell-specific overexpression of MYDGF mice model in the gain-of-function strategy. In in vitro experiments, coculture experiments between primary mouse aortic endothelial cells and macrophages and mouse aortic endothelial cells supplemented with or without recombinant MYDGF were conducted. RESULTS: Inflammatory cell-derived MYDGF deficiency aggravated endothelial LDL transcytosis, drove LDL uptake by artery wall, and thus exacerbated atherosclerosis in vivo. Inflammatory cell-derived MYDGF restoration by bone marrow transplantation and inflammatory cell MYDGF overexpression alleviated LDL transport across the endothelium, prevented LDL accumulation in the subendothelial space, and subsequently ameliorated atherosclerosis in vivo. Furthermore, in the in vitro study, macrophages isolated from MYDGF+/+ mice and recombinant MYDGF attenuated LDL transcytosis and uptake in mouse aortic endothelial cells. Mechanistically, MYDGF inhibited MAP4K4 (mitogen-activated protein kinase kinase kinase kinase isoform 4) phosphorylation, enhanced activation of Akt (protein kinase B)-1, and diminished the FoxO (forkhead box O) 3a signaling cascade to exert protective effects of MYDGF on LDL transcytosis and atherosclerosis. CONCLUSIONS: The findings support a role for inflammatory cell-derived MYDGF served as a cross talk factor between inflammatory cells and endothelial cells that inhibits LDL transcytosis across endothelium. MYDGF may become a novel therapeutic drug for atherosclerosis, and the beneficial effects of inflammatory cell in atherosclerosis deserve further attention.


Assuntos
Aterosclerose , Células Endoteliais , Camundongos , Animais , Células Endoteliais/metabolismo , Aterosclerose/genética , Aterosclerose/prevenção & controle , Aterosclerose/metabolismo , Lipoproteínas LDL/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo , Camundongos Knockout , Transcitose , Endotélio/metabolismo
4.
Nat Metab ; 4(11): 1573-1590, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36400933

RESUMO

Brown adipose tissue (BAT) activity contributes to cardiovascular health by its energy-dissipating capacity but how BAT modulates vascular function and atherosclerosis through endocrine mechanisms remains poorly understood. Here we show that BAT-derived neuregulin-4 (Nrg4) ameliorates atherosclerosis in mice. BAT-specific Nrg4 deficiency accelerates vascular inflammation and adhesion responses, endothelial dysfunction and apoptosis and atherosclerosis in male mice. BAT-specific Nrg4 restoration alleviates vascular inflammation and adhesion responses, attenuates leukocyte homing and reduces endothelial injury and atherosclerosis in male mice. In endothelial cells, Nrg4 decreases apoptosis, inflammation and adhesion responses induced by oxidized low-density lipoprotein. Mechanistically, protein kinase B (Akt)-nuclear factor-κB signaling is involved in the beneficial effects of Nrg4 on the endothelium. Taken together, the results reveal Nrg4 as a potential cross-talk factor between BAT and arteries that may serve as a target for atherosclerosis.


Assuntos
Tecido Adiposo Marrom , Aterosclerose , Neurregulinas , Animais , Masculino , Camundongos , Tecido Adiposo Marrom/metabolismo , Aterosclerose/metabolismo , Células Endoteliais/metabolismo , Endotélio , Inflamação/metabolismo , Neurregulinas/metabolismo
5.
Calcif Tissue Int ; 110(1): 131-142, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34383111

RESUMO

Osteoarthritis (OA) is characterized by chondrocyte apoptosis and increased degradation of type II collagen. Inflammation is one of the major risk factors involved in the pathophysiology of OA. Neuregulin 4 (Nrg4) plays a protective role in a variety of low-level inflammatory diseases, such as non-alcoholic fatty liver disease, inflammatory bowel disease, or type 2 diabetes mellitus. Here we found that (1) Nrg4 deficiency aggravated the destruction and inflammation of articular cartilage and the apoptosis of chondrocytes in vivo. (2) Nrg4 restoration reversed these changes in vivo. (3) Murine recombinant Nrg4 (rNrg4) suppressed inflammation and apoptosis of chondrocytes and decreased the degradation of extracellular matrix in vitro. (4) Mechanistically, the mitogen-activated protein kinase/c-jun N-terminal kinase (MAPK/JNK) signaling pathway may be involved in the regulation of Nrg4 in the pathophysiology of OA. Therefore, we concluded that Nrg4 alleviated the progression of OA by inhibiting the inflammation, protecting against apoptosis of chondrocyte, and decreasing the degradation of extracellular matrix in a manner involving MAPK/JNK signaling.


Assuntos
Apoptose , Cartilagem Articular , Condrócitos , Neurregulinas/genética , Osteoartrite , Animais , Células Cultivadas , Progressão da Doença , Inflamação , Camundongos , Osteoartrite/genética
6.
Am J Pharm Educ ; 84(5): 7683, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32577035

RESUMO

Objective. To use a fitness tracking device to track student wellness habits, specifically number of steps, activity, and sleep duration, in an attempt to identify relationships between these variables and academic performance outcomes such as examination scores and course grades. Methods. A fitness tracker was issued to second professional year Doctor of Pharmacy (PharmD) students to track their daily number of steps, activity levels, and minutes of sleep. Individual data from these devices were collected using a cloud-based data aggregation platform. The outcome variables of interest were student grade point average (GPA) in core courses, as well as examination grades for 17 examinations administered across eight required courses during the study period. After exploratory analyses, the primary research questions relating steps and sleep to academic performance were addressed with a series of linear regression models. Results. No significant, identifiable relationships were found between examination grades or course GPA and the variables of interest. There was a significant negative relationship between the number of steps students took 72-hours before an examination and performance on the examination where students in the low activity group significantly outperformed those in the high activity group by an average of two points. Participants took an average of 1,466 fewer steps prior to an examination. Conclusion. Sleep and physical activity were not robust predictors of examination scores and course grades in this cohort of PharmD students. While the fitness tracker served as an impetus for the students to be more cognizant of their activity, the capital expenditure for the devices did not result in improved academic performance.


Assuntos
Actigrafia/instrumentação , Educação em Farmácia , Escolaridade , Exercício Físico , Monitores de Aptidão Física , Sono , Estudantes de Farmácia , Avaliação Educacional , Feminino , Nível de Saúde , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
7.
Nano Lett ; 19(4): 2464-2471, 2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30860854

RESUMO

We report the experimental observation of radiative recombination from Rydberg excitons in a two-dimensional semiconductor, monolayer WSe2, encapsulated in hexagonal boron nitride. Excitonic emission up to the 4 s excited state is directly observed in photoluminescence spectroscopy in an out-of-plane magnetic field up to 31 T. We confirm the progressively larger exciton size for higher energy excited states through diamagnetic shift measurements. This also enables us to estimate the 1 s exciton binding energy to be about 170 meV, which is significantly smaller than most previous reports. The Zeeman shift of the 1 s to 3 s states, from both luminescence and absorption measurements, exhibits a monotonic increase of the g-factor, reflecting nontrivial magnetic-dipole-moment differences between ground and excited exciton states. This systematic evolution of magnetic dipole moments is theoretically explained from the spreading of the Rydberg states in momentum space.

8.
Nano Lett ; 18(6): 3516-3522, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29768012

RESUMO

Graphene, a single atomic layer of covalently bonded carbon atoms, has been investigated intensively for optoelectronics and represents a promising candidate for high-speed electronics. Here, we present a microwave mixer constructed as an asymmetrically contacted two-terminal graphene device based on the thermoelectric effect. We report a 50 GHz (minimum) mixer bandwidth as well as 130 V/W (163 mA/W) extrinsic direct-detection responsivity. Anomalous second-harmonic generation due to self-mixing in our graphene detector is also observed. Careful investigation of the responsivity from four different approaches gives consistent results, confirming the exceptional performance of our zero-bias device operating at room temperature. The 50 GHz bandwidth indicates an extremely fast response time and our experimental results represent an encouraging advance toward practical graphene microwave devices with anticipated future applications extended through millimeter wave and terahertz frequencies.

9.
Phys Rev Lett ; 120(4): 046402, 2018 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-29437416

RESUMO

We report the experimental observation of 2s exciton radiative emission from monolayer tungsten diselenide, enabled by hexagonal boron nitride protected high-quality samples. The 2s luminescence is highly robust and persists up to 150 K, offering a new quantum entity for manipulating the valley degree of freedom. Remarkably, the 2s exciton displays superior valley polarization and coherence than 1s under similar experimental conditions. This observation provides evidence that the Coulomb-exchange-interaction-driven valley-depolarization process, the Maialle-Silva-Sham mechanism, plays an important role in valley excitons of monolayer transition metal dichalcogenides.

10.
Sci Rep ; 6: 28024, 2016 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-27324297

RESUMO

Stokes and anti-Stokes Raman scattering are performed on atomic layers of hexagonal molybdenum ditelluride (MoTe2), a prototypical transition metal dichalcogenide (TMDC) semiconductor. The data reveal all six types of zone center optical phonons, along with their corresponding Davydov splittings, which have been challenging to see in other TMDCs. We discover that the anti-Stokes Raman intensity of the low energy layer-breathing mode becomes more intense than the Stokes peak under certain experimental conditions, and find the effect to be tunable by excitation frequency and number of atomic layers. These observations are interpreted as a result of resonance effects arising from the C excitons in the vicinity of the Brillouin zone center in the photon-electron-phonon interaction process.

11.
Nano Lett ; 15(8): 5295-301, 2015 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-26218887

RESUMO

Recent intense electrical and optical studies of graphene have pushed the material to the forefront of optoelectronic research. Of particular interest is the few terahertz (THz) frequency regime where efficient light sources and highly sensitive detectors are very challenging to make. Here we present THz sources and detectors made with graphene field effect transistors (GFETs) enhanced by a double-patch antenna and an on-chip silicon lens. We report the first experimental observation of 1-3 THz radiation from graphene, as well as more than 3 orders of magnitude performance improvements in a half-edge-contacted GFET thermoelectric detector operating at ∼2 THz. The quantitative analysis of the emitting power and its unusual charge density dependence indicate significant nonthermal noise contribution from the GFET. The polarization resolved detection measurements with different illumination geometries allow for detailed and quantitative analysis of various factors that contribute to the overall detector performance. Our experimental results represent a significant advance toward practically useful graphene THz devices.

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