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1.
Small ; 20(22): e2309176, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38150625

RESUMO

Metal nanoclusters providing maximized atomic surface exposure offer outstanding hydrogen evolution activities but their stability is compromised as they are prone to grow and agglomerate. Herein, a possibility of blocking metal ion diffusion at the core of cluster growth and aggregation to produce highly active Ru nanoclusters supported on an N, S co-doped carbon matrix (Ru/NSC) is demonstrated. To stabilize the nanocluster dispersion, Ru species are initially coordinated through multiple Ru─N bonds with N-rich 4'-(4-aminophenyl)-2,2:6',2''-terpyridine (TPY-NH2) ligands that are subsequently polymerized using a Schiff base. After the pyrolysis of the hybrid composite, highly dispersed ultrafine Ru nanoclusters with an average size of 1.55 nm are obtained. The optimized Ru/NSC displays minimal overpotentials and high turnover frequencies, as well as robust durability both in alkaline and acidic electrolytes. Besides, outstanding mass activities of 3.85 A mg-1 Ru at 50 mV, i.e., 16 fold higher than 20 wt.% Pt/C are reached. Density functional theory calculations rationalize the outstanding performance by revealing that the low d-band center of Ru/NSC allows the desorption of *H intermediates, thereby enhancing the alkaline HER activity. Overall, this work provides a feasible approach to engineering cost-effective and robust electrocatalysts based on carbon-supported transition metal nanoclusters for future energy technologies.

2.
J Craniofac Surg ; 35(4): e329-e333, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38376176

RESUMO

The use of eye-tracking technology in dental esthetics has gained popularity over the past decade because of its ability to assess observers' visual preferences in an objective manner. The goal of this study was to provide a comprehensive review of eye-tracking studies in dentistry, which could provide a reference for the rational and effective application of eye-tracking technology by dentists in the future. A comprehensive search of articles on eye tracking, published from January 1946 to June 2023, was conducted across several databases using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The major criterion for inclusion was that the study evaluated the use of eye-tracking technology in the field of dentistry. Two independent reviewers screened the eligible studies. A total of 67 articles were identified, 41 of which met our inclusion criteria. The most common application of eye tracking was the assessment of perceptions of changes in specific dental conditions among different classes of observers. Overall differences between groups (different classes of observers, different types of conditions) among different areas or regions of interest were analyzed. This systematic review demonstrated the utility of eye-tracking technology as a quantifiable objective assessment and emerging research tool for evaluating outcomes in several domains of dentistry.


Assuntos
Estética Dentária , Tecnologia de Rastreamento Ocular , Humanos
3.
J Transl Med ; 21(1): 921, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38115075

RESUMO

BACKGROUND: Metabolic dysfunction-associated fatty liver disease (MAFLD) is one of the most prevalent metabolic syndromes worldwide. However, no approved pharmacological treatments are available for MAFLD. Chenpi, one kind of dried peel of citrus fruits, has traditionally been utilized as a medicinal herb for liver diseases. Didymin is a newly identified oral bioactive dietary flavonoid glycoside derived from Chenpi. In this study, we investigated the therapeutic potential of Didymin as an anti-MAFLD drug and elucidated its underlying mechanisms. METHODS: High-fat diet (HFD)-induced MAFLD mice and alpha mouse liver 12 (AML12) cells were utilized to evaluate the effects and mechanisms of Didymin in the treatment of MAFLD. Liver weight, serum biochemical parameters, and liver morphology were examined to demonstrate the therapeutic efficacy of Didymin in MAFLD treatment. RNA-seq analysis was performed to identify potential pathways that could be affected by Didymin. The impact of Didymin on Sirt1 was corroborated through western blot, molecular docking analysis, microscale thermophoresis (MST), and deacetylase activity assay. Then, a Sirt1 inhibitor (EX-527) was utilized to confirm that Didymin alleviates MAFLD via Sirt1. Western blot and additional assays were used to investigate the underlying mechanisms. RESULTS: Our results suggested that Didymin may possess therapeutic potential against MAFLD in vitro and in vivo. By promoting Sirt1 expression as well as directly binding to and activating Sirt1, Didymin triggers downstream pathways that enhance mitochondrial biogenesis and function while reducing apoptosis and enhancing lipophagy. CONCLUSIONS: These suggest that Didymin could be a promising medication for MAFLD treatment. Furthermore, its therapeutic effects are mediated by Sirt1.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Sirtuína 1 , Animais , Camundongos , Sirtuína 1/metabolismo , Biogênese de Organelas , Simulação de Acoplamento Molecular , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Glicosídeos/farmacologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fígado/metabolismo
4.
Macromol Rapid Commun ; 44(17): e2300162, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37114515

RESUMO

Smoke emission and smoke toxicity have drawn more attention to improving the fire safety of polymers. In this work, a polyoxometalates (POMs)-based hybrids flame retardant (P-AlMo6 ) epoxy resin (EP) is prepared with toxicity-reduction and smoke-suppression properties via a peptide coupling reaction between POMs and organic molecules with double DOPO (bisDOPA). It combines the good compatibility of the organic molecule and the superior catalytic performance of POMs. Compared to pure EP, the glass transition temperature and flexural modulus of EP composite with 5 wt.% P-AlMo6 (EP/P-AlMo6 -5) are raised by 12.3 °C and 57.75%, respectively. Notably, at low flame-retardant addition, the average CO to CO2 ratio (Av-COY/Av-CO2 Y) is reduced by 33.75%. Total heat release (THR) and total smoke production (TSP) are lowered by 44.4% and 53.7%, respectively. The Limited Oxygen Index (LOI) value achieved 31.7% and obtained UL-94 V-0 rating. SEM, Raman, X-ray photoelectron spectroscopy, and TG-FTIR are applied to analyze the flame-retardant mechanism in condensed and gas phase. Outstanding flame retardant, low smoke toxicity properties are attained due to the catalytic carbonization ability of metal oxides Al2 O3 and MoO3 produced from the breakdown of POMs. This work advances the development of POMs-based hybrids flame retardants with low smoke toxicity properties.


Assuntos
Resinas Epóxi , Retardadores de Chama , Fumaça , Dióxido de Carbono , Polímeros
5.
Phys Chem Chem Phys ; 25(19): 13474-13486, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37132270

RESUMO

ß-Bi2O3 demonstrates excellent photocatalytic activity under visible light, but it has a very high photogenerated e--h+ recombination rate and quite low quantum efficiency. AgBr also shows excellent catalytic activity but Ag+ is easily reduced to Ag under light radiation, which limits its application in the photocatalysis field, and there are few reports about the application of AgBr in photocatalysis. In this study, the spherical flower-like porous ß-Bi2O3 matrix was first obtained, and then the spherical-like AgBr was embedded between the petals of the flower-like structure to avoid direct light radiation. The only light through the pores on the ß-Bi2O3 petals could be transmitted onto the surfaces of AgBr particles to form a nanometer point light source, which photo-reduced Ag+ on the surface of the AgBr nanospheres to construct the Ag-modified AgBr/ß-Bi2O3 embedded composite and a typical Z-scheme heterojunction was constructed. Under this bifunctional photocatalyst and visible light, the RhB degradation rate reached 99.85% in 30 min, and the photolysis water hydrogen production rate reached 6.288 mmol g-1 h-1. This work is as an effective method for not only the preparation of the embedded structure, quantum dot modification and flower-like morphology but also for the construction of Z-scheme heterostructures.

6.
J Craniofac Surg ; 34(2): 663-668, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36166498

RESUMO

This study compares postoperative enophthalmos between fresh and delayed unilateral orbital fractures after orbital reconstruction with titanium mesh using computer-assisted navigation. The sample was composed of 45 patients with post-traumatic unilateral enophthalmos who were divided into the fresh fracture group and the delayed fracture group. They underwent orbital reconstruction with standard preformed orbital implants and computer-assisted navigation system. The following parameters were measured with computed tomography images: the degree of enophthalmos, orbital volume, and fracture defect area. Patients were reviewed preoperatively (T0), 1 week postoperatively (T1), and 6 months postoperatively (T2). Computed tomography measurements showed that in both groups, the degree of enophthalmos decreased after surgery but increased significantly from T1 to T2 ( P <0.05). ΔE (difference in the degree of enophthalmos between T1 and T2) was similar in patients with fresh and delayed fractures. There was a significant difference in the degree of ΔE between patients with single-wall orbital fractures and those with two-wall orbital fractures. The findings indicate that postoperative enophthalmos is common in both the groups and is closely related to the degree of preoperative enophthalmos. Furthermore, the recurrence of enophthalmos is similar between the 2 groups, but it is higher in patients with orbital fractures involving 2 walls.


Assuntos
Implantes Dentários , Enoftalmia , Traumatismos Oculares , Fraturas Orbitárias , Humanos , Enoftalmia/cirurgia , Fraturas Orbitárias/cirurgia , Titânio , Telas Cirúrgicas , Computadores
7.
BMC Oral Health ; 23(1): 621, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37658390

RESUMO

BACKGROUND: Reconstruction of the temporomandibular joint (TMJ) is a significant challenge in maxillofacial surgery. A vascularized medial femoral condyle (MFC) osteocartilaginous flap is a good choice for TMJ reconstruction. In this study, we evaluated the radiographic and histological changes of MFC after TMJ reconstruction. METHODS: A ramus-condyle unit (RCU) defect was created unilaterally in five adult male Bama miniature pigs. The ipsilateral vascularized MFC osteocartilaginous flap was used to reconstruct the TMJ, and the non-operative sides served as controls. Multislice spiral computed tomography (CT) was performed preoperatively, immediately postoperatively, and at two weeks, three months, and six months postoperatively. Three animals were euthanized at 6 months postoperatively. Their reconstructed condyles, natural condyles and the MFCs on the opposite side were collected and subjected to µCT and histological evaluation. RESULTS: In the miniature pigs, the vascularized MFC osteocartilaginous flap was fused to the mandible, thus restoring the structure and function of the RCU. The postoperative radiographic changes and histological results showed that the reconstructed condyle was remodeled toward the natural condyle, forming a similar structure, which was significantly different from the MFC. CONCLUSIONS: In miniature pigs, the RCU can be successfully reconstructed by vascularized osteocartilaginous MFC flap. The reconstructed condyle had almost the same appearance and histological characteristics as the natural condyle.


Assuntos
Cirurgia Bucal , Articulação Temporomandibular , Masculino , Animais , Suínos , Porco Miniatura , Articulação Temporomandibular/diagnóstico por imagem , Articulação Temporomandibular/cirurgia , Mandíbula , Polímeros
8.
Pharm Biol ; 61(1): 228-240, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36655330

RESUMO

CONTEXT: Da-Yuan-Yin is a Chinese traditional prescription. OBJECTIVE: This study explores the therapeutic effects of the Da-Yuan-Yin decoction polyphenol fraction (DYY-4) on acute lung injury (ALI) in mice induced by lipopolysaccharide (LPS). MATERIALS AND METHODS: The mice (n = 10) were orally administrated with DYY-4 (15, 30, and 60 mg/kg) or DXM (5 mg/kg), half an hour after LPS (2 mg/kg) instilled intratracheally. The protein content and the levels of inflammatory factors, the levels of complements, the mRNA expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), the level of myeloperoxidase (MPO) and superoxide dismutase (SOD), the expression of the IkB kinase (IKK) and nuclear factor-kappa B (NF-κB), the lung wet-to-dry weight (W/D) ratio and lung tissue were evaluated, 24 h after LPS challenge. Network pharmacology predicted potential targets. RESULTS: DYY-4 (30, 60 mg/kg, p < 0.01, p < 0.01) decreased the lung W/D ratio, total protein concentration, the levels of C3, C3c and C5a, the levels of TNF-α, IL-6, and IL-1ß, while increased the levels of IL-4 and IL-10. DYY-4 (60 mg/kg) decreased the levels of C5aR1, C5b-9 and COX-2 mRNA (p < 0.05), the levels of MPO and iNOS mRNA, the activation of the IKK/NF-κB pathway (p < 0.01), and increased the levels of IL-13 and SOD (p < 0.01). DYY-4 (60 mg/kg) relieved the lung tissue pathological changes and reduced the C3c deposition. DISCUSSION AND CONCLUSIONS: Network pharmacology combined with animal experiments revealed the targets of DYY-4 alleviating ALI.


Assuntos
Lesão Pulmonar Aguda , NF-kappa B , Camundongos , Animais , NF-kappa B/metabolismo , Lipopolissacarídeos/toxicidade , Polifenóis/efeitos adversos , Ciclo-Oxigenase 2/genética , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/prevenção & controle , Pulmão , Superóxido Dismutase , RNA Mensageiro
9.
Nanotechnology ; 33(15)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-34488196

RESUMO

Hexagonal BCN (h-BCN) is considered to be a promising dielectric ceramic material with a hybrid B-C-N structure and an electromagnetic wave (EMW) absorbing material with tenable properties. H-BCN bulk and microtube architectures are simultaneously synthesized by precursor pyrolysis method using BCl3, aniline (AN) and diethylenetriamine (DETA) as the raw material. By analyzing its electromagnetic parameters, the effective absorption bandwidth of the sample cracking at 900 °C with the proportion of raw materials (DETA:AN = 1:1) can be up to 7.2 GHz, and the minimum reflection loss can reach -43.6 dB at 7.92 GHz with a thickness of 3.5 mm. Moreover, the EMW absorbing property of the ceramic can be tuned by adjusting the ratio of monomers, pyrolysis temperature, and cooling rates.

10.
Macromol Rapid Commun ; 43(23): e2200562, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35926186

RESUMO

The underlying trend of colloidal synthesis has focused on extending the structure and composition complexity of colloidal particles. Hollow and yolk-shell particles are successful examples that have potential applications in frontier fields. In this paper, a facile and controllable etching method based on the molecular exchange of the dynamic imine bond to generate cavities in polymer particles is developed. Starting from boronate ester polymer particles and inorganic@boronate core-shell particles with the imine bonds incorporated in the polymer networks, the etching method easily affords hollow and yolk-shell particles with tunable shell thicknesses. The molecular exchange dynamics analysis indicates that guest amine molecules cause the reconstruction of imine bonds and the leakage of molecular and oligomer fragments, resulting in the formation of the hollow structure. This molecular exchange-based etching method may be of interest in the construction of polymer architectures with increased composition and structure complexities.

11.
Clin Oral Investig ; 26(6): 4593-4601, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35218428

RESUMO

OBJECTIVES: This study aimed to evaluate the accuracy and reliability of convolutional neural networks (CNNs) for the detection and classification of mandibular fracture on spiral computed tomography (CT). MATERIALS AND METHODS: Between January 2013 and July 2020, 686 patients with mandibular fractures who underwent CT scan were classified and annotated by three experienced maxillofacial surgeons serving as the ground truth. An algorithm including two convolutional neural networks (U-Net and ResNet) was trained, validated, and tested using 222, 56, and 408 CT scans, respectively. The diagnostic performance of the algorithm was compared with the ground truth and evaluated by DICE, accuracy, sensitivity, specificity, and area under the ROC curve (AUC). RESULTS: One thousand five hundred six mandibular fractures in nine subregions of 686 patients were diagnosed. The DICE of mandible segmentation using U-Net was 0.943. The accuracies of nine subregions were all above 90%, with a mean AUC of 0.956. CONCLUSIONS: CNNs showed comparable reliability and accuracy in detecting and classifying mandibular fractures on CT. CLINICAL RELEVANCE: The algorithm for automatic detection and classification of mandibular fractures will help improve diagnostic efficiency and provide expertise to areas with lower medical levels.


Assuntos
Fraturas Mandibulares , Algoritmos , Humanos , Fraturas Mandibulares/diagnóstico por imagem , Redes Neurais de Computação , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos
12.
BMC Infect Dis ; 21(1): 207, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33627079

RESUMO

BACKGROUND: A large-scale global outbreak of coronavirus disease-19 (COVID-19) out of Wuhan, from China, occurred in January 2020. To examine the clinical characteristics of COVID-19 in infected patients out of Wuhan, from China. METHODS: Thirteen patients were confirmed to be infected with novel coronavirus-2019 (2019-nCoV) between January 27 and February 8, 2020, in Baoji city, Shannxi, northwestern China. Epidemiological and clinical information, and computed to morphology imaging data from all COVID-19 patients were collected; cases were divided into two groups according to the severity of infection (mild or severe). RESULTS: Nine (9/13) COVID-19 patients exhibited mild disease severity, and defined as second-generation human-to-human transmission cases. Most patients (11/13) had a history of travel to or from Wuhan. There were no differences in sex and age between the mild and severe cases (all P > 0.05). A moderate degree of fever (11/13), cough (13/13), and fatigue (8/13) were common symptoms; however, there was no statistical difference between mild and severe cases in this regard (all P > 0.05). Oxyhemoglobin saturation and oxygenation index decreased, and C-reactive protein (CRP) and serum amyloid A (SAA) levels were elevated in all patients with COVID-19 infection, with statistically significant differences between those with severe disease and mild infection (all P < 0.05). Twelve of 13 COVID-19 patients exhibited changes in chest CT imaging features, and time course changes were different between mild and severe cases (all P < 0.05). CONCLUSION: Most cases of COVID-19 infection were second-generation human-to-human transmissions from Wuhan and were mild in severity. The clinical characteristics of COVID-19 varied. Oxyhemoglobin saturation, oxygenation index, CRP and SAA levels, and CT features were reliable parameters to evaluate the severity of COVID-19 infection. However, a few patients with mild COVID-19 disease lacked typical characteristics such as fever and changes in CT imaging features.


Assuntos
COVID-19/complicações , SARS-CoV-2 , Adulto , Idoso , Proteína C-Reativa/análise , COVID-19/sangue , COVID-19/epidemiologia , Estudos de Casos e Controles , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteína Amiloide A Sérica/análise , Tomografia Computadorizada por Raios X
13.
Mol Cancer ; 19(1): 71, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32241279

RESUMO

BACKGROUND: Colon cancer (CC) is a common malignant cancer. Recently, circFNDC3B was found to exert biological function in multiple cancers. However, it was unclear whether the potential protein encoded by circFNDC3B is involved in carcinogenesis of CC. METHODS: We used Sanger sequence and RNase R digestion assay to confirm the existence of circFNDC3B, and quantitative real-time PCR was used to evaluate the circRNA's expression. Then fluorescence in situ hybridization (FISH) was performed to study location of circFNDC3B. The identification of protein encoded by circFNDC3B was performed using LC-MS/MS. The function of circFNDC3B-218aa on proliferation, invasion and migration were assessed by CCK8 assays, colony formation assays, transwell assays, wound-healing assays and animal experiments. RNA-sequencing and western blot were used to identify the gene regulated by circFNDC3B-218aa. Finally, glucose metabolism-related assays were performed to further investigate function of circFNDC3B-218aa. RESULTS: CircFNDC3B was localized mostly in the cytoplasm, and was decreased in CC cell lines and tissues. The patients with low circFNDC3B expression had a shorter OS (P = 0.0014) than patients with high expression. Moreover, circFNDC3B inhibited the proliferation, invasion and migration of CC cells. Next, we identified that circFNDC3B could encode a novel protein circFNDC3B-218aa. Furthermore, circFNDC3B-218aa, not circFNDC3B, inhibited the proliferation, invasion and migration of CC. Additionally, the in vivo experiments implied that up-regulated circFNDC3B-218aa exhibited an inhibitory effect on CC progression. By RNA-sequencing, western blot and glucose metabolism-related assays, we found that circFNDC3B-218aa inhibited the expression of Snail, and subsequently promoted the tumor-suppressive effect of FBP1 in CC. CONCLUSIONS: The novel circFNDC3B-218aa may serve as a tumor suppressive factor and potential biomarker which may supply the potential therapeutic target for CC.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias do Colo/patologia , Transição Epitelial-Mesenquimal , Fibronectinas/genética , Regulação Neoplásica da Expressão Gênica , RNA Circular/genética , Fatores de Transcrição da Família Snail/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , Fatores de Transcrição da Família Snail/genética , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Nanotechnology ; 31(25): 255710, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32050191

RESUMO

Electromagnetic wave (EMW) induction of shape memory polymer (SMP) composites with multifunctional inorganic fillers is a high efficiency, uniform, and non-contact method. Herein, the shape memory effect of ternary BCN/Fe3O4/PCL composites induced by EMWs are explored. The components of Fe3O4 and the BCN nanotubes serve as wave-absorbing materials. The electromagnetic properties and EMW absorption performance of BCN/Fe3O4/PCL are discussed in detail. The EMWs absorbed by BCN/Fe3O4/PCL are dissipated by dielectric loss and magnetic loss. The shape memory mechanism of BCN/Fe3O4/PCL is based on the Fe3O4 and BCN nanotubes dissipating absorbed EMW energy into heat to boost the temperature of the composites, thereby responding to EMW remote control. This work introduces a new direction for SMPs induced by EMWs as potential candidates in the application of shape recovery in a restricted space.

15.
Nanotechnology ; 30(18): 185704, 2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-30650393

RESUMO

FexOy/Fe decorated graphite sheets (DGS) are synthesized using a facile coprecipitation method followed by heat treatment under different conditions. The size and chemical composition of the particles loaded on graphite sheets can be tailored by adjusting the heat treatment temperature and atmosphere. The obtained α-Fe2O3 DGS (S1), Fe3O4 DGS (S2 and S3), and Fe DGS (S4) all exhibit excellent electromagnetic (EM) wave absorption when compared with conventional graphite/magnetic-particle composites. The minimum reflection loss (RL) can reach -42.1 dB at 4.16 GHz in the S2/paraffin composites. The bandwidth of the RL below -10 dB covers 4.4 GHz (11.04-15.44 GHz) with a thickness of 2 mm. A possible EM wave loss mechanism has been proposed in detail. The multiple absorbing mechanisms could control the excellent absorption, resulting in a product with a feasible application in stealth materials.

16.
Bioconjug Chem ; 29(2): 420-430, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29261297

RESUMO

Doxorubicin is an effective and widely used cancer chemotherapeutic agent, but its application is greatly compromised by its cumulative dose-dependent side effect of cardiotoxicity. A gold nanoparticle-based drug delivery system has been designed to overcome this limitation. Five novel thiolated doxorubicin analogs were synthesized and their biological activities evaluated. Two of these analogs and PEG stabilizing ligands were then conjugated to gold nanoparticles, and the resulting Au-Dox constructs were evaluated. The results show that release of native drug can be achieved by the action of reducing agents such as glutathione or under acidic conditions, but reductive drug release gave the cleanest drug release. Gold nanoparticles (Au-Dox) were prepared with different loadings of PEG and doxorubicin, and one formulation was evaluated for mammalian stability and toxicity. Plasma levels of doxorubicin in mice treated with Au-Dox were significantly lower than in mice treated with the same amount of doxorubicin, indicating that the construct is stable under physiological conditions. Treatment of mice with Au-Dox gave no histopathologically observable differences from mice treated with saline, while mice treated with an equivalent dose of doxorubicin showed significant histopathologically observable lesions.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Ouro/química , Nanopartículas Metálicas/química , Neoplasias/tratamento farmacológico , Animais , Antibióticos Antineoplásicos/sangue , Antibióticos Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/sangue , Doxorrubicina/uso terapêutico , Humanos , Masculino , Camundongos , Neoplasias/patologia
17.
Nanotechnology ; 29(23): 235701, 2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29517489

RESUMO

Carbon-based materials have excited extensive interest for their remarkable electrical properties and low density for application in electromagnetic (EM) wave absorbents. However, the processing of heteroatoms doping in carbon nanostructures is an insuperable challenge for attaining effective reflection loss and EM matching. Herein, a facile method for large-scale synthesis of boron and nitrogen doped carbon nanotubes decorated by ferrites particles is proposed. The BCN nanotubes (50-100 nm in diameter) imbedded with nanosized Fe x (B/C/N) y (10-20 nm) are successfully constructed by two steps of polymerization and carbonthermic reduction. The product exhibits an outstanding reflection loss (RL) performance, in that the minimum RL is -47.97 dB at 11.44 GHz with a broad bandwidth 11.2 GHz (from 3.76 to 14.9 GHz) below -10 dB indicating a competitive absorbent in stealth materials. Crystalline and theoretical studies of the absorption mechanism indicate a unique dielectric dispersion effect in the absorbing bandwidth.

18.
Nanotechnology ; 28(35): 355708, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28636565

RESUMO

Carbon nanofibers decorated with porous carbon nanotubes were prepared by electrospinning and annealing methods. The microwave reflection loss of the products was investigated in the frequency range of 2-18 GHz. The bandwidth with a reflection loss less than -10 dB covers a wide frequency, ranging from 7.0 to 14.1 GHz with thickness of 3.0-5.5 mm, and the minimum reflection loss is -44.5 dB at 10.7 GHz with thickness of 2.0 mm. The large reflection loss and wide reflection band reveal that the products could be a promising candidate for microwave absorption.

19.
Sci Rep ; 14(1): 14338, 2024 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-38906920

RESUMO

Previous research has produced inconsistent findings concerning the connection between metabolic syndrome and prostate cancer. It is challenging for observational studies to establish a conclusive causal relationship between the two. However, Mendelian randomization can provide stronger evidence of causality in this context. To examine the causal link between a metabolic composite and its components with prostate cancer, we performed a two-sample Mendelian randomization (MR) study utilizing aggregated data from genome-wide association studies, followed by meta-analyses. In our study, we employed inverse variance weighting as the primary method for MR analysis. Additionally, we assessed potential sources of heterogeneity and horizontal pleiotropy through the Cochran's Q test and MR-Egger regression. Moreover, we used multivariate MR to determine whether smoking versus alcohol consumption had an effect on the outcomes. We found no causal relationship between metabolic syndrome and its components and prostate cancer(MetS, odds ratio [OR] = 0.95, 95% confidence interval [CI] = 0.738-1.223, p = 0.691; TG, [OR] = 1.02, 95%[CI] = 0.96-1.08, p = 0.59); HDL, [OR] = 1.02, 95% [CI] = 0.97-1.07, p = 0.47; DBP, [OR] = 1.00, 95%[CI] = 0.99-1.01, p = 0.87; SBP, [OR] = 1.00, 95%[CI] = 0.99-1.00, p = 0.26; FBG [OR] = 0.92, 95%[CI] = 0.81-1.05, p = 0.23; WC, [OR] = 0.93, 95%[CI] = 0.84-1.03, p = 0.16). Finally, the MVMR confirms that the metabolic syndrome and its components are independent of smoking and alcohol consumption in prostate cancer. We didn't find significant evidence to determine a causal relationship between the metabolic syndrome and its components and prostate cancer through MR analysis. Further research is necessary to explore the potential pathogenesis between the two diseases.


Assuntos
Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Síndrome Metabólica , Neoplasias da Próstata , Humanos , Masculino , Síndrome Metabólica/genética , Neoplasias da Próstata/genética , Fatores de Risco , Consumo de Bebidas Alcoólicas/efeitos adversos , Razão de Chances , Fumar/efeitos adversos , Polimorfismo de Nucleotídeo Único
20.
Carbohydr Polym ; 326: 121610, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38142072

RESUMO

Inspired by "disappear after reading", a time-modulated encryption hydrogel was synthesized by carboxymethyl cellulose with carbon quantum dots. Carboxymethyl cellulose in this system stabilized carbon quantum dots, which ensured the whole hydrogel worked well. The encryption/decryption of information depended on pH adjustment, application of EDTA and Cr (VI). Furthermore, an in-depth analysis of the fluorescence change mechanism uncovered that fluorescence quenching was potentially influenced by internal filtering effects and static quenching, which involved the amino, carboxyl, and hydroxyl groups present within the hydrogel.

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