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1.
Opt Lett ; 48(12): 3223-3226, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37319067

RESUMO

We report a thin-film circular polarizer consisting of three metal-grid layers to be used with a photoconductive antenna (PCA) to generate terahertz (THz) circularly polarized (CP) radiation. The polarizer has a high transmission with a measured 3 dB axial-ratio bandwidth of 54.7% from 0.57 to 1 THz. We further developed a generalized scattering matrix approach to provide insight into the underlying physical mechanism of the polarizer. We revealed that the Fabry-Pérot-like multi-reflection among gratings enables the high-efficiency polarization conversion. The successful realization of the CP PCA can find widespread application, such as THz circular dichroism spectroscopy, THz Mueller imaging, and ultrahigh-speed THz wireless communications.

2.
J Endovasc Ther ; : 15266028231208653, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37902436

RESUMO

PURPOSE: To describe and compare mid-term outcomes from 2 real-world data collection efforts on fenestrated and branched endovascular aortic repair (fbEVAR) for complex abdominal aortic aneurysms (AAAs) in France and to evaluate the potential of health care databases for long-term post-market surveillance (PMS) and continued reimbursement approval. METHODS: Two real-world studies were conducted in France: a retrospective health care database study (SNDS) and a prospective clinical study. In the SNDS study, data from implantation and/or hospital stays occurring during follow-up were extracted for all patients treated with the study devices from April 2012 to December 2018. In the clinical study, high-risk patients undergoing fbEVAR with the study devices were enrolled consecutively at 15 sites in France from December 2016 to November 2018. RESULTS: Data from 1073 patients were extracted from SNDS and compared with analogous variables from 186 patients in the clinical study. Most demographic details were similar between studies (SNDS vs clinical: mean age, 71.9 vs 71.8 years; men, 91.0% vs 89.8%), as was 30-day mortality (SNDS: 5.5%, clinical: 4.3%). Patients received custom-made fenestrated or branched devices (SNDS: 80.7%, clinical: 96.2%) or CE-marked Zenith Fenestrated devices (SNDS: 19.3%, clinical: 3.8%). Initial or technical success was above 94% for both studies. Two-year freedom from all-cause mortality was 80.0% (SNDS) and 85.1% (clinical study). Two-year freedom from aneurysm-related mortality was 93.8% (SNDS) and 94.6% (clinical study). Detailed imaging outcomes were not captured within SNDS; however, information on secondary procedures to restore patency was available and used as a surrogate measure for secondary interventions. Two-year freedom from secondary interventions was 73% for the SNDS study. In the clinical study, at 2 years, aneurysm stability or shrinkage was observed in 92.3% of patients, freedom from target vessel primary patency loss was above 95% for all visceral target vessels, and freedom from secondary interventions was 79.1%. CONCLUSION: Real-world outcomes from the SNDS and clinical study suggest positive mid-term outcomes in high-risk populations following fbEVAR for complex AAAs. The similarities between these studies suggest that the use of health care databases may be an alternative to prospective clinical studies for long-term follow-up and PMS. CLINICAL IMPACT: Positive results following endovascular repair of complex abdominal aortic aneurysms are observed from data extracted from both the French health care database and a post-market clinical study despite initial high-risk patient status and diverse center experience. These outcomes parallel more rigorously designed studies and suggest that with careful study design, real-world data collections have high translatable value to add to the clinical understanding of fenestrated and branched endovascular aortic repair (fbEVAR).

3.
Opt Express ; 29(10): 14853-14867, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33985198

RESUMO

Mueller matrix polarimetry (MMP) has been demonstrated and recognized as an effective approach to attaining imaging enhancement as well as revealing polarization properties of an imaged sample. Generally, a minimum of 16 combinations of intensity-only measurements involving both linear and circular polarizations are required to completely and accurately determine the 4 × 4 Mueller matrix (MM) and comprehensively describe the polarization properties of the sample. However, broadband circular polarizations (CP) are rather difficult to obtain for design and fabrication limitations in the terahertz region, which poses a challenge to the acquisition of the 4 × 4 MM. In this circumstance, the 3 × 3 MM degradation using only linear polarizations (LP) is preferred and sufficient for characterization of non-depolarizing samples. In this paper, a multi-spectral 3 × 3 MMP system based on the THz time-domain spectroscopy (THz-TDS) is established from 0.1 to 1 THz. The system demonstrated is capable of fulfilling the accurate determination of the 3 × 3 MM. The Mueller matrix polar decomposition (MMPD), modified to be compatible with the MM degradation, is employed to explore the fine details and properties of the sample. By signal post-processing techniques, the MM elements in the time domain are retrieved, and the time dimension reflecting the depth information facilitates the 3D reconstruction of the sample. This work provides a prototype for 3D imaging of biological samples at higher frequencies in the future.

4.
World J Surg ; 45(4): 1031-1042, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33462704

RESUMO

BACKGROUND: Reporting guidelines and study registration can minimize bias and improve the reporting quality of biomedical research, but may not be fully utilized. The objective of this study was to investigate the policies of surgery journals as for reporting guidelines and study registration and explore associated journal characteristic variables. METHODS: Study samples were obtained from the Expanded Science Citation Index of the 2018 Journal Citation Reports (surgery category). The online guides for authors were browsed to identify which journals endorsed reporting guidelines and study registration. The predictors related to the endorsement were explored by using Chi-square test and multivariate logistic regression analysis, respectively. RESULTS: One hundred and eighty-eight surgery journals were included in our study. One hundred and sixty-three journals (86.7%) endorsed reporting guidelines and 103 journals (54.8%) endorsed study registration. About reporting guidelines, ICMJE (International Committee of Medical Journal Editors) recommendations were the most frequently endorsed (n = 155, 82.4%) by journals, followed by CONSORT (Consolidated Standards of Reporting Trials) statement (n = 94, 50.0%). About study registration, randomized controlled trial registration was endorsed by 101 (53.7%) journals, whereas the systematic review registration was endorsed by only 9 journals (4.8%). The results of multivariate logistic regression analysis revealed that not North America, higher JCR (Journal Citation Reports) rank journals were more likely to endorse reporting guidelines and study registration. CONCLUSIONS: Surgery journals frequently use reporting guidelines, but nearly half of journals did not require study registration. Implementing these two mechanisms can prevent bias, and their adoption should be strengthened by authors, reviewers and journal editors in surgery.


Assuntos
Pesquisa Biomédica , Publicações Periódicas como Assunto , Estudos Transversais , Políticas Editoriais , Fidelidade a Diretrizes , Humanos
5.
Entropy (Basel) ; 23(4)2021 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-33920703

RESUMO

Ship-radiated noise is one of the important signal types under the complex ocean background, which can well reflect physical properties of ships. As one of the valid measures to characterize the complexity of ship-radiated noise, permutation entropy (PE) has the advantages of high efficiency and simple calculation. However, PE has the problems of missing amplitude information and single scale. To address the two drawbacks, refined composite multi-scale reverse weighted PE (RCMRWPE), as a novel measurement technology of describing the signal complexity, is put forward based on refined composite multi-scale processing (RCMP) and reverse weighted PE (RWPE). RCMP is an improved method of coarse-graining, which not only solves the problem of single scale, but also improves the stability of traditional coarse-graining; RWPE has been proposed more recently, and has better inter-class separability and robustness performance to noise than PE, weighted PE (WPE), and reverse PE (RPE). Additionally, a feature extraction scheme of ship-radiated noise is proposed based on RCMRWPE, furthermore, RCMRWPE is combined with discriminant analysis classifier (DAC) to form a new classification method. After that, a large number of comparative experiments of feature extraction schemes and classification methods with two artificial random signals and six ship-radiated noise are carried out, which show that the proposed feature extraction scheme has better performance in distinguishing ability and stability than the other three similar feature extraction schemes based on multi-scale PE (MPE), multi-scale WPE (MWPE), and multi-scale RPE (MRPE), and the proposed classification method also has the highest recognition rate.

6.
Carcinogenesis ; 41(3): 274-283, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31605605

RESUMO

Polymerase I and transcript release factor (PTRF)/Cavin1 regulates RNA polymerase I during transcription and plays a critical role in endocytosis. Abnormal expressions of PTRF were detected in multiple cancers according to increasing research. PTRF has been showed to involve in the formation and secretion of exosomes and can be detected in the exosomes, which suggests that PTRF would be a potential biomarker for diagnosis of clear cell renal cell carcinoma (ccRCC) using urine samples. Approximately 50-90% of ccRCC cases suffered abnormal epidermal growth factor receptor (EGFR), which activates a variety of signaling pathways, including the mitogen-activated protein kinase/extracellular signal-regulated kinase and Phosphoinositide 3-Kinase/Akt pathway. According to bioinformatic analysis of gene expression arrays of kidney clear cell carcinoma from The Cancer Genome Atlas, we found SHC1 was significantly overexpressed in high-grade ccRCC and correlated to poor prognosis, and also SHC1 was annotated in extracellular matrix process, which was regulated by EGFR. Further studies showed that the expression of PTRF was regulated by SHC1 through EGFR-Phosphoinositide 3-Kinase/Akt pathway. PTRF was detected in the exosomes isolated from ccRCC patients' urine and ccRCC cancer cells culture medium. It suggested that the abnormal SHC1-increased PTRF, which is detected in exosomes from urine, would be a potential marker for ccRCC diagnose and treatment.


Assuntos
Carcinoma de Células Renais/genética , Proteínas de Ligação a RNA/genética , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/urina , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/urina , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Receptores ErbB/genética , Exossomos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Prognóstico , Proteínas de Ligação a RNA/urina , Transdução de Sinais , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/urina
7.
Am J Otolaryngol ; 41(3): 102403, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31982209

RESUMO

PURPOSE: Laryngopharyngeal reflux (LPR) accounts for 4-10% of outpatient visits. The standard domestic LPR diagnostic tools are the reflux finding score (RFS) and reflux symptom index (RSI). Narrow band imaging (NBI) can identify previously unknown characteristic microvessel features. Our aim was to explore the role of NBI in LPR diagnosis. MATERIALS AND METHODS: We recruited 56 LPR outpatients and 41 symptom-negative controls. All individuals received RSI and RFS scores and underwent 24-hour multichannel intraluminal impedance-PH (MII-pH) monitoring and endoscopic NBI before and after treatment. The positivity rates in the study and control groups, before and after treatment, and using NBI and the conventional method were evaluated. RESULTS: Fifty-one LPR and six control patients had sparse light brownish dots or tufted light brownish dots in the postcricoid region. The RSI and RFS positivity rates were 31.3% and 87.1%, respectively. NBI is as effective as the RFS (P < 0.05), and has poor consistency with the RSI (P < 0.05). Fifty-three LPR patients underwent posttreatment laryngoscopy. The positivity rate decreased to 17.0% (P < 0.05). CONCLUSION: NBI has good value for LPR diagnosis.


Assuntos
Refluxo Laringofaríngeo/diagnóstico , Imagem de Banda Estreita , Adulto , Monitoramento do pH Esofágico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
J Neuroeng Rehabil ; 11: 97, 2014 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-24908048

RESUMO

BACKGROUND: The need of a sensory feedback system that would improve users' acceptance in prostheses is generally recognized. Feedback of hand opening and position are among the most important concerns of prosthetic users. To address the two concerns, this study investigated the human capability to identify pulse number and location when electrical stimulation applied on the forearm skin. The pulse number may potentially be used to encode the opening of prosthetic hands and stimulation location to encode finger position. METHODS: Ten able-bodied subjects participated in the study. Three electrodes were placed transversely across the ventral forearm spatially encoding three fingers (i.e., thumb, index, and middle finger). Five different pulse numbers (1, 4, 8, 12, and 20) encoded five levels of hand opening. The study consisted of three experiments. In the three experiments, each after a training session, the subjects were required to identify among: (a) five stimulation locations, (b) five pulse numbers, or (c) ten paired combinations of location and pulse number, respectively. The subjects' performance in the three identification tasks was evaluated. RESULTS: The main results included: 1) the overall identification rate for stimulation location was 92.2 ± 6.2%, while the success rate in two-site stimulation was lower than one-site stimulation; 2) the overall identification rate for pulse number was 90.8 ± 6.0%, and the subjects showed different performance in identification of the five pulse numbers; 3) the overall identification rate decreased to 80.2 ± 11.7% when the subjects were identifying paired parameters. CONCLUSIONS: The results indicated that the spatial (location) and temporal (pulse number) identification performance are promising in electrocutaneous stimulation on the forearm. The performance degraded when both parameters had to be identified likely due to increased cognitive load resulting from multiple tasks. Utilizing the proposed coding strategy in practical prosthetic hands remains to be investigated for clinical evaluation of its feasibility.


Assuntos
Membros Artificiais , Retroalimentação Sensorial/fisiologia , Antebraço/inervação , Desenho de Prótese , Limiar Sensorial/fisiologia , Adulto , Atenção/fisiologia , Estimulação Elétrica , Feminino , Humanos , Masculino
9.
Oncogene ; 43(18): 1386-1396, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38467852

RESUMO

Clear cell renal cell carcinoma (ccRCC) presents a unique profile characterized by high levels of angiogenesis and robust vascularization. Understanding the underlying mechanisms driving this heterogeneity is essential for developing effective therapeutic strategies. This study revealed that ubiquitin B (UBB) is downregulated in ccRCC, which adversely affects the survival of ccRCC patients. UBB exerts regulatory control over vascular endothelial growth factor A (VEGFA) by directly interacting with specificity protein 1 (SP1), consequently exerting significant influence on angiogenic processes. Subsequently, we validated that DNA methyltransferase 3 alpha (DNMT3A) is located in the promoter of UBB to epigenetically inhibit UBB transcription. Additionally, we found that an unharmonious UBB/VEGFA ratio mediates pazopanib resistance in ccRCC. These findings underscore the critical involvement of UBB in antiangiogenic therapy and unveil a novel therapeutic strategy for ccRCC.


Assuntos
Carcinoma de Células Renais , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais , Neovascularização Patológica , Fator de Transcrição Sp1 , Fator A de Crescimento do Endotélio Vascular , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/irrigação sanguínea , Carcinoma de Células Renais/tratamento farmacológico , Humanos , Neoplasias Renais/patologia , Neoplasias Renais/genética , Neoplasias Renais/irrigação sanguínea , Neoplasias Renais/metabolismo , Neoplasias Renais/tratamento farmacológico , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição Sp1/genética , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Linhagem Celular Tumoral , Animais , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Indazóis/farmacologia , Indazóis/uso terapêutico , DNA Metiltransferase 3A/metabolismo , Sulfonamidas/farmacologia , Camundongos , Ubiquitina/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regiões Promotoras Genéticas , Feminino , Masculino , Angiogênese
10.
Sci Total Environ ; 933: 172935, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38703859

RESUMO

The deleterious impact of pollution point sources on the surrounding environment and human has long been a focal point of environmental research. When considering the local atmospheric dispersion of semi-volatile organic compounds (SVOCs) around the emission sites, it is essential to account the dynamic process for the gas/particle (G/P) partitioning, which involves the transition from an initial state to a steady state. In this study, we have developed a model that enables the prediction of the dynamic process for G/P partitioning of SVOCs, particularly considering the influence from emission. It is important to note that the dynamic processes of the concentrations of SVOCs in particle phase (CP) and in gas phase (CG) differ significantly. These differences arise due to the influence of two critical factors: particulate proportion of SVOCs in the emissions (ϕ0) and octanol-air partitioning coefficient (KOA). The validity of our model was assessed by comparing its predictions of the extremum value of the G/P partitioning quotient (KP) with the results obtained from the steady-state model. Remarkably, the characteristic time (tC), used to evaluate the timescale required for SVOCs to reach steady state, demonstrated different variations with KOA for CP and CG. Additionally, the values of tC were quite different for CP and CG, which were markedly influenced by ϕ0. For some SVOCs with high KOA values, it took approximately 35 h to reach steady state. Furthermore, it was found that the time to achieve 95 % of steady state (t95 ≈ 3tC) could reach approximately 105 h. This duration is sufficient for chemicals to disperse from their emission site to the surrounding areas. Therefore, it is crucial to consider the dynamic process of G/P partitioning in local atmospheric transport studies. Moreover, the influence of ϕ0 should be incorporated into future investigations examining the dynamic process of G/P partitioning.

11.
ISA Trans ; 133: 273-284, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35811158

RESUMO

Dispersion Lempel-Ziv complexity (DLZC) and multiscale DLZC (MDLZC) are very recently introduced complexity indicators to quantify the dynamic change of time series in acoustics signals. They introduce the mapping steps of dispersion entropy (DE), which can effectively identify time series with different characteristics, but ignore the fluctuation information and have poor stability. In order to overcome these shortcomings, this paper firstly adds fluctuation information to DLZC and proposes fluctuation-based DLZC (FDLZC) as an alternative to the classical time series complexity index, followed by introducing an improved coarse-graining operation to propose the refined composite multiscale FDLZC (RCMFDLZC), which increases the number of features and also ensures the stability of FDLZC, and finally select the subsequence containing the most information by the minimum redundancy maximum relevance (mRMR) feature selection algorithm for subsequent experiments. The experimental results show that the extracted RCMFDLZC features have the strongest separability and better clustering effect in both bearing fault signals and ship radiated noise signals, and the RCMFDLZC-based signal analysis method also has higher recognition rate compared with other methods in bearing fault diagnosis and ship signal classification.

12.
J Colloid Interface Sci ; 633: 155-165, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36436348

RESUMO

The Gibbs free energy of hydrogen adsorption at the edge of molybdenum disulfide (MoS2) is close to that of Pt, meaning that MoS2 is the best candidate to replace Pt-based materials. However, easy agglomeration between layers to mask active sites, lack of catalytic activity in the basal planes, and poor electronic conductivity make MoS2 exhibit dissatisfactory hydrogen evolution reaction (HER) catalytic performance. Here, we successfully construct a van der Waals heterostructure stacked alternately with Mo(SSe)2-x and graphene (Mo(SSe)2-x/G) to enhance its catalytic ability. The introduction of Se into MoS2 and the thermal treatment induce the sample to generate more anion vacancies. Theoretical and experimental results demonstrate the constructed van der Waals heterostructure, the introduced Se element, and the increased anion vacancies are in favor of promoting the number of active sites and improving the electronic conductivity of the catalyst. Therefore, Mo(SSe)2-x/G exhibits superior HER catalytic performance (the overpotentials of 137 mV and 136 mV at a current of 10 mA cm-2) and long-term stabilities (>90 h and 140 h at a current density of 20 mA cm-2) in both acidic and alkaline media.

13.
Front Pharmacol ; 14: 1333507, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38178861

RESUMO

Background: Clear cell renal cell carcinoma (ccRCC) stands as the prevailing variant kidney cancer in humans. Unfortunately, patients with disseminated RCC at diagnosis often have a diminished prognosis. Rapid tumor growth necessitates efficient blood supply for oxygen and nutrients, involving the circulation of blood from vessels to tumor tissues, facilitating tumor cell entry into the extracellular matrix. Vasculogenic mimicry (VM) significantly contributes to tumor growth and metastasis. Within this investigation, we identified vasculogenic mimicry-related genes (VMRGs) by analyzing data from 607 cases of kidney renal clear cell carcinoma (KIRC) in The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) database (https://www.ncbi.nlm.nih.gov/geo/). These findings offer insights into ccRCC progression and metastasis. Method: We identified VMRGs-related subtypes using consistent clustering methods. The signature of the VMRGs was created using univariate Cox regression and LASSO Cox regression analyses. To evaluate differences in immune cell infiltration, we employed ssGSEA. Afterwards, we created an innovative risk assessment model, known as the VM index, along with a nomogram to forecast the prognosis of ccRCC. Additionally, we verified the expression of an important gene related to VM, peroxiredoxin 2 (PRDX2), in tissue samples. Furthermore, we assessed the sensitivity to drugs in various groups by utilizing the pRRophetic R package. Results: Significant predictors of survival rates in both high- and low-risk groups of KIRC patients were identified as VMRGs. The independent prognostic factors for RCC were confirmed by both univariate and multivariate Cox regression analyses, validating VMRG risk signatures. Differences were observed in drug sensitivity, immune checkpoint expression, and responses to immune therapy between patients classified into high- and low-VMRG-risk groups. Our nomograms consistently demonstrated precise predictive capabilities. Finally, we experimentally verified PRDX2 expression levels and their impact on prognosis. Conclusion: The signature predicts patient prognosis and therapy response, laying the groundwork for future clinical strategies in treating ccRCC patients.

14.
Sci Adv ; 9(4): eadf8478, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36706183

RESUMO

The sixth-generation (6G) communication technology is being developed in full swing and is expected to be faster and better than the fifth generation. The precise information transfer directivity and the concentration of signal strength are the key topics of 6G technology. We report the synthetic phase design of rotary doublet Airy beam and triplet Gaussian beam varifocal meta-devices to fully control the terahertz beam's propagation direction and coverage area. The focusing spot can be delivered to arbitrary positions in a two-dimensional plane or a three-dimensional space. The highly concentrated signal can be delivered to a specific position, and the transmission direction can be adjusted freely to enable secure, flexible, and high-directivity 6G communication systems. This technology avoids the high costs associated with extensive use of active components. 6G communication systems, wireless power transfer, zoom imaging, and remote sensing will benefit from large-scale adoption of such a technology.

15.
Nat Commun ; 14(1): 5155, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37620303

RESUMO

Metasurfaces have promising potential to revolutionize a variety of photonic and electronic device technologies. However, metasurfaces that can simultaneously and independently control all electromagnetics (EM) waves' properties, including amplitude, phase, frequency, polarization, and momentum, with high integrability and programmability, are challenging and have not been successfully attempted. Here, we propose and demonstrate a microwave universal metasurface antenna (UMA) capable of dynamically, simultaneously, independently, and precisely manipulating all the constitutive properties of EM waves in a software-defined manner. Our UMA further facilitates the spatial- and time-varying wave properties, leading to more complicated waveform generation, beamforming, and direct information manipulations. In particular, the UMA can directly generate the modulated waveforms carrying digital information that can fundamentally simplify the architecture of information transmitter systems. The proposed UMA with unparalleled EM wave and information manipulation capabilities will spark a surge of applications from next-generation wireless systems, cognitive sensing, and imaging to quantum optics and quantum information science.

16.
Inorg Chem ; 51(4): 1998-2009, 2012 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-22309171

RESUMO

The alkaloid oxoglaucine (OG), which is a bioactive component from traditional Chinese medicine (TCM), was synthesized by a two-step reaction and used as the ligand to react with transition metal salts to give four complexes: [OGH][AuCl(4)]·DMSO (1), [Zn(OG)(2)(H(2)O)(2)](NO(3))(2) (2), [Co(OG)(2)(H(2)O)(2)](ClO(4))(2) (3), and [Mn(OG)(2)(H(2)O)(2)](ClO(4))(2) (4). The crystal structures of the metal complexes were confirmed by single crystal X-ray diffraction. Complex 1 is an ionic compound consisting of a charged ligand [OGH](+) and a gold complex [AuCl(4)](-). Complexes 2-4 all have similar structures (inner-spheres), that is, octahedral geometry with two OG coordinating to one metal center and two aqua ligands occupying the two apical positions of the octahedron, and two NO(3)(-) or ClO(4)(-) as counteranions in the outer-sphere. The complexation of OG to metal ion was confirmed by ESI-MS, capillary electrophoresis and fluorescence polarization. The in vitro cytotoxicity of these complexes toward a various tumor cell lines was assayed by the MTT method. The results showed that most of these metal-oxoglaucine complexes exhibited enhanced cytotoxicity compared with oxoglaucine and the corresponding metal salts, with IC(50) values ranging from 1.4 to 32.7 µM for sensitive cancer cells, which clearly implied a positive synergistic effect. Moreover, these complexes appeared to be selectively active against certain cell lines. The interactions of oxoglaucine and its metal complexes with DNA and topoisomerase I were investigated by UV-vis, fluorescence, CD spectroscopy, viscosity, and agarose gel electrophoresis, and the results indicated that these OG-metal complexes interact with DNA mainly via intercalation. Complexes 2-4 are metallointercalators, but complex 1 is not. These metal complexes could effectively inhibit topoisomerase I even at low concentration. Cell cycle analysis revealed that 1-3 caused S-phase cell arrest.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Apomorfina/análogos & derivados , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Animais , Apomorfina/química , Apomorfina/farmacologia , Bovinos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Cristalografia por Raios X , DNA/metabolismo , DNA Topoisomerases Tipo I/metabolismo , Humanos , Modelos Moleculares , Neoplasias/tratamento farmacológico , Inibidores da Topoisomerase I/química , Inibidores da Topoisomerase I/farmacologia , Elementos de Transição/química , Elementos de Transição/farmacologia
17.
Biotechnol Appl Biochem ; 59(4): 270-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23586860

RESUMO

Cinnamyl acetate was synthesized using immobilized lipase through transesterification between ethyl acetate and cinnamyl alcohol. In the solvent-free system, ethyl acetate acted as not only the acyl donor but also as the solvent of cinnamyl alcohol. Conversion (90.06%) was achieved after 3 H when transesterification was carried out at ethyl acetate/cinnamyl alcohol 15:1, 2.67 g L of lipase (Novozym 435) loading, and 40°C. Excellent stability and reusability of the enzyme resulted from the moderate reaction system. Kinetic studies showed that the Michaelis constants for ethyl acetate and cinnamyl alcohol and the inhibition constant of cinnamyl alcohol were 2.241, 206.82, and 0.461 mmol L⁻¹, respectively, which indicated that the reaction complied with the Ping-Pong Bi-Bi mechanism, with the inhibition of cinnamyl alcohol on lipase.


Assuntos
Biocatálise , Lipase/metabolismo , Propanóis/síntese química , Candida/enzimologia , Técnicas de Química Sintética , Esterificação , Cinética , Lipase/química , Modelos Químicos , Temperatura
18.
PeerJ ; 10: e12837, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35127293

RESUMO

BACKGROUND: A journal's impact factor (IF) and total citations are often used as indicators of its publication quality. Furthermore, journals that require authors to abide by reporting guidelines or conduct trial registration generally have a higher quality of reporting. In this study, we sought to explore the potential associations between the enforcement of reporting guidelines or trial registration and a surgical journal's IF or total citations in order to find new approaches and ideas to improve journal publication quality. METHODS: We examined surgical journals from the 2018 Journal Citation Report's Expanded Scientific Citation Index to quantify the use of reporting guidelines or study registration. We reviewed the "instructions for authors" from each journal and used multivariable linear regression analysis to determine which guidelines were associated with the journal IF and total citations. The dependent variable was the logarithm base 10 of the IF in 2018 or the logarithm base 10 of total citations in 2018 (the results were presented as geometric means, specifically the ratio of the "endorsed group" results to "not endorsed group" results). The independent variable was one of the requirements (endorsed and not endorsed). Models adjust for the publication region, language, start year, publisher and journal size (only used to adjust total citations). RESULTS: We included 188 surgical journals in our study. The results of multivariable linear regression analysis showed that journal IF was associated (P < 0.01) with the following requirements: randomized controlled trial (RCT) registration (geometric means ratio (GR) = 1.422, 95% CI [1.197-1.694]), Consolidated Standards of Reporting Trials (CONSORT) statement (1.318, [1.104-1.578]), Preferred Reporting Items for Systematic Reviews Meta-Analyses (PRISMA) statement (1.390, [1.148-1.683]), Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement (1.556, [1.262-1.919]), Standards for Reporting Diagnostic Accuracy (STARD) statement (1.585, [1.216-2.070]), and Meta-analysis of Observational Studies in Epidemiology (MOOSE) statement (2.113, [1.422-3.133]). We found associations between the endorsement of RCT registration (GR = 1.652, 95% CI [1.268-2.153]), CONSORT (1.570, [1.199-2.061]), PRISMA (1.698, [1.271-2.270]), STROBE (2.023, [1.476-2.773]), STARD (2.173, [1.452-3.243]), and MOOSE statements (2.249, [1.219-4.150]) and the number of total citations. CONCLUSION: The presence of reporting guidelines and trial registration was associated with higher IF or more total citations in surgical journals. If more surgical journals incorporate these policies into their submission requirements, this may improve publication quality, thus increasing their IF and total citations.


Assuntos
Fator de Impacto de Revistas , Publicações Periódicas como Assunto , Coleta de Dados , Registros , Padrões de Referência
19.
J Colloid Interface Sci ; 619: 148-157, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35381483

RESUMO

Metal-organic frameworks (MOFs) with intrinsically porous structures and well-dispersed metal sites are promising candidates for the oxygen evolution reaction (OER). However, the practical applications of MOFs for OER are significantly constrained due to their poor charge transfer property and insufficient inherent activity. Herein, we utilized caffeic acid as a bridging agent to covalently bond FeNi-MOF with NiMoO4 in order to tune the charge transfer properties for efficient OER. The optimized organic-inorganic heterocatalyst demonstrates superior OER performance with a low overpotential of 256 mV at a current density of 10 mA cm-2 and long-term stability, outperforming the benchmark IrO2 catalyst and single counterparts. Both experimental and theoretical results indicate that electrons can be transferred from FeNi-MOF to NiMoO4 via a caffeic acid bridging agent, which improves not only the electrical conductivity but also the adsorption capacity of OH- intermediates on MOFs. Therefore, the enhanced OER activity of the heterocatalyst is attributed to the synergistic effects of the multi-components. This study paves the way for the rational design of MOFs-based heterostructures towards efficient electrocatalytic oxygen evolution.

20.
Front Immunol ; 13: 934387, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958561

RESUMO

Background: Poor prognosis of kidney renal clear cell carcinoma (KIRC) is often related to angiogenesis. The lncRNAs that regulate angiogenesis could also affect the prognosis of KIRC. It is meaningful for us to use lncRNAs related to angiogenesis to construct a generic, individualized prognostic signature for patients with KIRC. Methods: We identified eight angiogenesis-associated genes (AAGs) by differential expression analysis and univariate Cox regression from The Cancer Genome Atlas dataset, including 537 KIRC samples and 72 normal samples. In total, 23 prognostic lncRNAs were screened out after Pearson correlation analysis and univariate Cox regression analysis. Then, we performed least absolute shrinkage and selection operator (LASSO) regression and multivariate Cox regression to establish a four-AAG-related lncRNA prognostic signature. Results: The risk score was calculated for each KIRC patients by using a four-AAG-related lncRNA prognostic signature. We divided the KIRC patients into high- and low-risk groups by the median of the risk score. It was confirmed that the AAG-related lncRNA prognostic signature has good prognostic value for KIRC patients by time-dependent receiver operating characteristic and Kaplan-Meier survival analysis. We identified 3,399 differentially expressed genes between the high- and low-risk groups and performed their functional enrichment analyses. The AAG-related lncRNA prognostic signature was an independent prognostic predictor for KIRC patients and was used to perform a combined nomogram. We reevaluated them in terms of survival, clinic characteristics, tumor-infiltrating immune cells and tumor mutation burden. Conclusion: Our research indicates that the AAG-related lncRNA prognostic signature is a promising and potential independent prognostic indicator for KIRC patients. Then, it could offer new insights into the prognosis assessment and potential treatment strategies of KIRC patients.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , RNA Longo não Codificante , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Rim/patologia , Neoplasias Renais/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
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