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1.
Opt Express ; 31(25): 42240-42254, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38087602

RESUMO

Non-line-of-sight (NLOS) imaging can visualize a remote object out of the direct line of sight and can potentially be used in endoscopy, unmanned vehicles, and robotic vision. In an NLOS imaging system, multiple diffusive reflections of light usually induce large optical attenuation, and therefore, a sensitive and efficient photodetector, or, their array, is required. Limited by the spectral sensitivity of the light sensors, up to now, most of the NLOS imaging experiments are performed in the visible bands, and a few at the near-infrared, 1550 nm. Here, to break this spectral limitation, we demonstrate a proof-of-principle NLOS imaging system using a fractal superconducting nanowire single-photon detector, which exhibits intrinsic single-photon sensitivity over an ultra-broad spectral range. We showcase NLOS imaging at 1560- and 1997-nm two wavelengths, both technologically important for specific applications. We develop a de-noising algorithm and combine it with the light-cone-transform algorithm to reconstruct the shape of the hidden objects with significantly enhanced signal-to-noise ratios. We believe that the joint advancement of the hardware and the algorithm presented in this paper could further expand the application spaces of the NLOS imaging systems.

2.
ACS Appl Mater Interfaces ; 15(29): 34451-34461, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37458210

RESUMO

Constant oxidative stress at the wound site prolongs the inflammation period and slows down the proliferation stage. In order to shorten the inflammatory period meanwhile promote the proliferative activity of fibroblasts, herein, we synthesized novel camelina-derived carbon dots (CDs) decorating on hFGF2-linked camelina lipid droplets (CLD-hFGF2) to form nanobiomaterial CDs-CLD-hFGF2. The CDs-CLD-hFGF2 possesses peroxidase activity and has effective reactive oxygen species radical scavenging activity while achieving proliferation of NIH/3T3 cells under oxidative stress in vitro. In the acute wound model, wound healing after CDs-CLD-hFGF2 treatment reached nearly 92% on the 10th day, compared with 82% for CLD-hFGF2. Moreover, the wound site showed significant anti-inflammatory effects characterized by the downregulation of pro-inflammatory factors and the upregulation of anti-inflammatory factor levels. Overall, this study provided a strategy for the comprehensive utilization of camelina oil crops and revealed a promising future that could be considered an effective method for wound healing on the skin.


Assuntos
Carbono , Gotículas Lipídicas , Camundongos , Animais , Carbono/farmacologia , Cicatrização , Pele , Antioxidantes
3.
Colloids Surf B Biointerfaces ; 222: 113089, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36527806

RESUMO

Bacterial infection wounds are common in life. At present, although various wound materials have shown antibacterial activity, there is a lack of overall strategy to promote wound healing. Therefore, it is necessary to develop multifunctional wound materials. In this study, silver nanoparticles (Ag NPs) modified camelina oil bodies (OB) which surface covalently bonded human fibroblast growth factor 2 (Ag NPs-hFGF2-OB) were designed for the treatment of bacterial infection wounds. The prepared Ag NPs-hFGF2-OB not only act as an antibacterial agent to realize sterilization, but also act as a tissue repair agent that effectively promotes wound healing. Ag+ was reduced in situ to Ag NPs by ascorbic acid, and the activity of hFGF2 protein was not affected after hFGF2-OB was modified by Ag NPs, which displaying broad apectrum antibacterial ability for both S. aureus and E. coli, with an antibacterial rate of more than 70 % (the concentration of Ag NPs was 20 µg/mL, the hFGF2 protein concentration was 20 µg/mL). Ag NPs-hFGF2-OB can effectively promote the migration of NIH/3T3 cells, showing good biocompatibility. The mouse bacterial infection wound model experiments proved that the wound healing rate of Ag NPs-hFGF2-OB group (the concentration of Ag NPs was 20 µg/mL, the hFGF2 protein concentration was 20 µg/mL) was much higher than other treatment groups, especially on the 7th day after treatment, the wound healing rate reached 71.71 ± 2.38 %, while the healing rate of other treatment groups were only 34.54 ± 1.10 %, 37.08 ± 2.85 % and 47.99 ± 2.01 %. Therefore, Ag NPs-hFGF2-OB, which can inhibit bacterial growth, promotes collagen deposition, granulation tissue regeneration and angiogenesis without any significant toxicity, shows good potential for application in the repair of bacterial infection wounds.


Assuntos
Infecções Bacterianas , Nanopartículas Metálicas , Camundongos , Animais , Humanos , Prata/farmacologia , Staphylococcus aureus , Escherichia coli , Gotículas Lipídicas , Cicatrização , Antibacterianos/farmacologia
4.
ACS Appl Mater Interfaces ; 14(48): 53491-53500, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36416503

RESUMO

Rapid wound closure and bacterial inactivation are effective strategies to promote wound healing. Herein, a versatile nanoglue, bismuth tungstate (Bi2WO6)-silver sulfide (Ag2S) direct Z-scheme heterostructure nanoparticles (BWOA NPs), was designed to accelerate wound healing. BWOA NPs' hollow structure and rough surface could effectively close wound tissues acting as a barrier between external bacteria and the wound. More importantly, the unique Z-scheme heterostructure endows BWOA NPs with an effective electron and hole separating ability with potent redox potential, where electrons and holes could effectively react with water and oxygen to produce reactive oxygen species, leading to a higher antibacterial activity against both endogenous and external bacteria at the wound site. A series of in vitro and in vivo biological assessments demonstrated that BWOA NPs could rapidly close wounds and promote wound healing. With sunlight irradiation, the inhibiting rates of BWOA NPs against Escherichia coli and Staphylococcus aureus are 61.62 ± 2.85 and 73.40 ± 3.28%, respectively. Also, the wound healing rate in BWOA NP-treated mice is 25.90 ± 5.85% higher than PBS. This design provides a new effective strategy to promote bacterial inactivation and accelerate wound healing.


Assuntos
Bismuto , Prata , Animais , Camundongos , Bismuto/farmacologia , Prata/farmacologia , Bactérias
5.
Ageing Res Rev ; 72: 101480, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34601136

RESUMO

Vascular aging is a major cause of morbidity and mortality in the elderly population. Endothelial cells (ECs) and vascular smooth muscle cells (VSMCs), forming the intima and media layers of the vessel wall respectively, are closely associated with the process of vascular aging and vascular aging-related diseases. Numerous studies have revealed the pathophysiologic mechanism through which lncRNA contributes to vascular aging, hence more attention is now paid to the role played by antisense long non-coding RNA (AS-lncRNA) in the pathogenesis of vascular aging. Nonetheless, only a small number of studies focus on the specific mechanism through which AS-lncRNA mediates vascular aging. In this review, we summarize the roles and functions of AS-lncRNA with regards to the development of vascular aging and vascular aging-related disease. We also aim to deepen our understanding of this process and provide alternative therapeutic modalities for vascular aging-related diseases.


Assuntos
RNA Longo não Codificante , Idoso , Envelhecimento/genética , Células Endoteliais , Humanos , Músculo Liso Vascular , Miócitos de Músculo Liso , RNA Longo não Codificante/genética
6.
Small ; 17(38): e2101607, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34365727

RESUMO

Zinc-air batteries (ZABs) are promising as energy storage devices owing to their high energy density and the safety of electrolytes. Construction of abundant triple-phase boundary (TPB) effectively facilitates cathode reactions occurring at TPB. Herein, a wood-derived integral air electrode containing Co/CoO nanoparticles and nitrogen-doped carbonized wood (Co/CoO@NWC) is constructed with a dual catalytic function. The potential gap between oxygen reduction and evolution is shortened to 0.77 V. Liquid ZABs using Co/CoO@NWC as cathode exhibit high discharge specific capacity (800 mAh gZn-1 ), low charge-discharge gap (0.84 V), and long-term cycling stability (270 h). Co/CoO@NWC also shows distinguished catalytic activity and stability in all-solid-state ZABs. The inherent layered porous and pipe structures of wood are well maintained in catalytically active carbon. The different hydrophilicity of carbonized wood and Co/CoO endow abundant TPBs for battery reaction. The Co/CoO located on TPB provides main active sites for oxygen reactions. The inherent pipe structures of wood carbon and the interaction between Co/CoO and NWC effectively prevent nanoparticles from aggregation. The design and preparation of this monolithic electrocatalyst contribute to the broad-scale application of ZABs and promote the development of next-generation biomass-based storage devices.


Assuntos
Madeira , Zinco , Carbono , Fontes de Energia Elétrica , Eletrodos
7.
J Phys Chem A ; 125(19): 4209-4215, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-33977714

RESUMO

A new strategy by manipulating the progress of triplet energy transfer (TET) is developed to realize adjustable multicolor and pure white emission. Donor phosphorescent molecules emits light when encapsulated into polyvinyl alcohol (PVA) through hydrogen bond interactions, and acceptor fluorescent molecules emits light when doped into PVA through cation-π interactions and hydrogen bond interactions. In addition, the triplet to singlet energy transfer process and mechanism are proved using the energy diagram and lifetime. The broadband emission color of the obtained composite film can be easily modulated by simply adjusting the amount and component of dyes, especially the white emission with CIE coordinates of (0.339, 0.337). This work provides a facile and versatile method for the development of multicolor and pure white-light-emitting diodes, which uses the interactions to light up luminescence properties, and can further aid in the wide development of applications for TET in various other fields.

8.
Chem Commun (Camb) ; 57(35): 4303-4306, 2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33913949

RESUMO

An ultrafast, non-invasive and large-scale visualization method has been developed to evaluate the dispersion of two-dimensional nanosheets in aqueous solution with a fluorescence microscope by the formation of excimers from the improvement of cation-π interactions.

9.
Magn Reson Imaging ; 63: 80-84, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31425800

RESUMO

PURPOSE: To investigate the correlation of magnetic resonance imaging (MRI), apparent diffusion coefficient (ADC) and intravoxel incoherent motion imaging parameters with Ki-67 expression in cholangiocarcinoma. METHODS: A total of 42 extrahepatic cholangiocarcinoma (EHCC) cases confirmed by surgical pathology were analyzed retrospectively. Subjects underwent MRI at 3.0 T and intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) sequential scanning prior to surgery, and postoperative Ki-67 expression was recorded by immunohistochemistry (IHC). The patients were divided into 4 groups (I-IV) based on increasing Ki-67 expression from - to +++. ADC values and IVIM-DWI parameters were calculated, including true diffusion coefficient (D), perfusion fraction (f), and pseudo-diffusion coefficient (D*). The comparison among groups was analyzed by univariate ANOVA (normal distribution) or Kruskal-Wallis H (non-normal distribution). Spearman correlation analysis was used to analyze the correlation of each parameter with Ki-67 expression. The diagnostic efficiency of each parameter was compared using the area under the curve (AUC) of the receiver operating characteristic (ROC) curve. RESULTS: Except for D*, other values had statistically significant differences between groups (P < 0.05). ADC, D and f values had negative correlations with Ki-67 expression (r values were -0.607, -0.795, -0.531, respectively, P < 0.05). The AUCs were 0.701, 0.880, 0.623, respectively (P < 0.0001). CONCLUSION: IVIM-DWI technology can reflect the proliferative activity of EHCC cells to a certain extent, and has clinical value for predicting the degree of malignancy of a tumor.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico por imagem , Colangiocarcinoma/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Antígeno Ki-67/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Perfusão , Curva ROC , Estudos Retrospectivos
10.
J Colloid Interface Sci ; 529: 432-443, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29945015

RESUMO

A solvothermal-assisted evaporation-induced self-assembly (SA-EISA) approach has been developed for the synthesis of ordered mesoporous alumina (OMA) materials with high thermal stability and improved performance in catalysis. In conventional EISA process, the evaporation step is accompanied by the hydrolysis of organic aluminum precursors, thus the evaporation conditions have significant influences on the reaction and the final structure of OMA. In our approach, the solvothermal treatment step promotes the complete hydrolysis of aluminum precursors and produces partially condensed cluster-like aluminum hydroxyl species, which allows the formation of OMA in a broad range of evaporation conditions. Compared to mesoporous alumina obtained by conventional EISA process, OMA materials prepared by SA-EISA approach exhibit higher specific surface area, pore volume and thermal stability. When used as supporting materials for vanadium oxide catalyst, OMA materials obtained by the SA-EISA approach exhibit excellent activity, selectivity and stability for ethylbenzene dehydrogenation with carbon dioxide as a mild oxidant. Our contribution has provided new understanding in the synthesis of OMA materials with improved performance for catalytic applications.

11.
Acta Radiol ; 55(9): 1031-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24280135

RESUMO

BACKGROUND: Coronary to pulmonary artery fistula (CPAF) is rare; reports on the prevalence and types of CPAF in a large cohort of patients are scarce. PURPOSE: To analyze the prevalence and types of CPAF on computed tomography coronary angiography (CTCA) in a large Chinese population. MATERIAL AND METHODS: CTCA data of 58,533 patients from five Chinese tertiary referral medical centers were retrospectively studied. The prevalence, origin, aneurysmal sac, fistula tracts, and extracardiac communication of CPAF were recorded. CTCA findings were compared with conventional coronary angiography when possible. RESULTS: Ninety-nine patients had CPAF (prevalence of 0.17%). Of the 99 CPAF cases, fistulas were found to originate from either both coronary arteries in 52 patients or from one coronary artery (33 cases from the left and 14 cases from the right coronary artery). Ten CPAF patients were complicated with the communication of extracardiac arteries. Fifteen (15.2%) CPAF patients had aneurysmal sac formation. Thirty (30.3%) patients had a single fistula tract, while 69 (69.7%) patients had multiple fistula tracts. CTCA findings in 16 patients were similar to those at DSA. CONCLUSION: Based on this large cohort, the prevalence of CPAF in the Chinese population is about 0.17%, with origin from either the left or right coronary artery or from both. CTCA can clearly visualize the types, abnormal vascular tracts, and aneurysmal sac formation of CPAF.


Assuntos
Fístula Artério-Arterial/diagnóstico por imagem , Angiografia Coronária/métodos , Vasos Coronários/diagnóstico por imagem , Artéria Pulmonar/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Fístula Artério-Arterial/epidemiologia , Técnicas de Imagem de Sincronização Cardíaca , China/epidemiologia , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos
13.
Eur J Radiol ; 81(11): 2961-5, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22285604

RESUMO

OBJECTIVES: To measure the sensitivity of diffusion-weighted imaging (DWI) and determine the most appropriate b value for DWI; to explore the correlation between the apparent diffusion coefficient (ADC) value and the degree of extrahepatic cholangiocarcinoma differentiation. METHODS: Preoperative diffusion-weighted imaging and magnetic resonance examinations were performed for 31 patients with extrahepatic cholangiocarcinoma. Tumor ADC values were measured, and the signal-to-noise ratio, contrast-to-noise ratio, and signal-intensity ratio between the diffusion-weighted images with various b values as well as the T2-weighted images were calculated. Pathologically confirmed patients were pathologically graded to compare the ADC value with different b values of tumor at different degrees of differentiation, and the results were statistically analyzed by using the Friedman test. RESULTS: A total of 29 cases of extrahepatic cholangiocarcinoma were detected by DWI. As the b value increased, tumor signal-to-noise ratio and contrast-to-noise ratio between the tumor and normal liver gradually decreased, but the tumor signal-intensity ratio gradually increased. When b=800 s/mm2, contrast-to-noise ratio between tumor and normal liver, tumor signal-intensity ratio, and tumor signal-to-noise ratio of diffusion-weighted images were all higher than those of T2-weighted images; the differences were statistically significant (P<0.05). As the b value increased, the tumor ADC value gradually declined. As the degree of differentiation decreased, the tumor ADC value declined. CONCLUSION: The b value of 800 s/mm2 was the best in DWI of extrahepatic cholangiocarcinoma; the lesion ADC value declined as the degree of cancerous tissue differentiation decreased.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Extra-Hepáticos/patologia , Colangiocarcinoma/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
World J Gastroenterol ; 16(25): 3196-201, 2010 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-20593506

RESUMO

AIM: To determine the clinical value of diffusion-weighted imaging (DWI) for the diagnosis of extrahepatic cholangiocarcinoma (EHCC) by comparing the diagnostic sensitivity of DWI and magnetic resonance cholangiopancreatography (MRCP). METHODS: Magnetic resonance imaging examination was performed in 56 patients with suspected EHCC. T1-weighted imaging, T2-weighted imaging, MRCP and DWI sequence, DWI using single-shot spin-echo echo-planar imaging sequence with different b values (100, 300, 500, 800 and 1000 s/mm(2)), were performed. All cases were further confirmed by surgery or histopathological diagnosis. Two radiologists jointly performed the analysis of the DWI and MRCP images. Apparent diffusion coefficient (ADC) value and signal-noise ratio were calculated for EHCC. Sensitivity, specificity, accuracy, positive predictive value and negative predictive value were tested using DWI with a b value of 500 s/mm(2) and MRCP images, respectively. RESULTS: Histopathological diagnosis confirmed that among the 56 cases, 35 were EHCC (20 hilar and 15 distal extrahepatic), 16 were cholangitis, and 5 were calculus of bile duct. Thirty-three out of the 35 EHCC cases were detected by DWI. EHCC exhibited differential levels of high signal intensity in DWI and low signal intensity in the ADC map. The mean value for ADC was (1.31 +/- 0.29) x 10(-3) mm(2)/s. The detection rate of EHCC was significantly higher by DWI (94.3%) than by MRCP (74.3%) (P < 0.05). There was a significant difference in sensitivity (94.3% vs 74.3%), specificity (100% vs 71.4%), accuracy (96.4% vs 73.2%), positive predictive value (100% vs 81.3%), and negative predictive value (91.3% vs 62.5%) between DWI and MRCP in diagnosing EHCC. CONCLUSION: DWI has a high sensitivity for the detection of EHCC as it shows the EHCC lesion more unambiguously than MRCP does. DWI can also provide additional clinically important information in EHCC patients when added to routine bile duct MR imaging protocols.


Assuntos
Neoplasias dos Ductos Biliares , Ductos Biliares Intra-Hepáticos/patologia , Colangiocarcinoma , Colangiopancreatografia por Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Adulto , Idoso , Neoplasias dos Ductos Biliares/diagnóstico , Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/patologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
15.
World J Gastroenterol ; 15(26): 3303-8, 2009 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-19598308

RESUMO

AIM: To optimize the preoperative diagnosis and surgical management of adult intussusception (AI). METHODS: A retrospective review of the clinical features, diagnosis, management and pathology 41 adult patients with postoperative diagnoses of intussusception was conducted. RESULTS: Forty-one patients with 44 intussusceptions were operated on, 24.4% had acute symptoms, 24.4% had subacute symptoms, and 51.2% had chronic symptoms. 70.7% of the patients presented with intestinal obstruction. There were 20 enteric, 15 ileocolic, eight colocolonic and one sigmoidorectal intussusceptions. 65.9% of intussusceptions were diagnosed preoperatively using a computed tomography (CT) scan (90.5% accurate) and ultrasonography (60.0% accurate, rising to 91.7% for patients who had a palpable abdominal mass). Coloscopy located the occupying lesions of the lead point of ileocolic, colocolonic and sigmoidorectal intussusceptions. Four intussusceptions in three patients were simply reduced. Twenty-one patients underwent resection after primary reduction. There was no mortality and anastomosis leakage perioperatively. Except for one patient with multiple small bowel adenomas, which recurred 5 mo after surgery, no patients were recurrent within 6 mo. Pathologically, 54.5% of the intussusceptions had a tumor, of which 27.3% were malignant. 9.1% comprised nontumorous polyps. Four intussusceptions had a gastrojejunostomy with intestinal intubation, and four intussusceptions had no organic lesion. CONCLUSION: CT is the most effective and accurate diagnostic technique. Colonoscopy can detect most lead point lesions of non-enteric intussusceptions. Intestinal intubation should be avoided.


Assuntos
Intussuscepção/diagnóstico , Intussuscepção/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Intussuscepção/etiologia , Intussuscepção/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
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