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1.
Artigo em Inglês | MEDLINE | ID: mdl-34623267

RESUMO

Medical ultrasound image quality is often limited by clutter, which is the dominant mechanism of the image degradation. A variety of beamforming methods have been extensively studied to reduce clutter and thus enhance ultrasound image quality. This paper introduces a new beamforming approach, called covariance matrix-based statistical beamforming (CMSB), to improve the image contrast and preserve the background speckle pattern, while simultaneously achieving a high resolution performance. In CMSB, adaptive selection of subarray length, diagonal reducing, and mean-to-standard-deviation ratio based subarray averaging are inherently combined to differentiate and reduce off-axis energy effectively. Moreover, rotary averaging prior to diagonal reducing is introduced to preserve speckle statistics. Simulated, experimental, and in vivo datasets were used to evaluate the imaging performance of the proposed method. The quantitative results indicate that, compared with delay and sum (DAS) beamforming, CMSB leads to average improvements of 44.5% and 97.3% in lateral resolution and contrast, respectively, in phantom experiments. Our work shows that CMSB is capable of improving image resolution and contrast while maintaining the speckle reliably. Preliminary in vivo study also demonstrates that the CMSB can enhance image contrast and lesion detection.

2.
Chemphyschem ; 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34643984

RESUMO

Laser induced thermal effect is inevitable in the up-conversion particle assisted near-infrared polymerization (UCAP). In this article, the influence of thermal effect on the polymerization behavior is investigated. The effects of up-conversion particles content and NIR laser intensity on the polymerization rate and surface oxygen inhibition were systematically investigated, and the temperature evolution and complex viscosity changes in the polymerization system during the polymerization process were also monitored. In addition, polymerization experiments conducted on a controlled temperature platform were used to study the effect of NIR heating on the polymerization behavior. The results show that the near-infrared thermal effect promotes the polymerization reaction, but also causes severe oxygen inhibition which has an adverse effect on polymerization. Finally, NIR curing materials with enhanced mechanical properties than those of conventional UV curing materials were obtained.

3.
EBioMedicine ; 71: 103558, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34521054

RESUMO

BACKGROUND: Resistance to platinum-based chemotherapy is a major cause of therapeutic failure during the treatment of epithelial ovarian cancer (EOC) patients. Our study aims to elucidate the molecular mechanisms by which ZNF711 down regulation promotes CISPLATIN resistance in EOC. METHODS: ZNF711 expression in 150 EOC specimens was examined using immunohistochemistry. ZNF711 expression and the survival of EOC patients were assessed with a Kaplan-Meier analysis. The effects of ZNF711 expression on CDDP resistance were studied by IC50, Annexin V, and colony formation in vitro, and in an in vivo intra-peritoneal tumor model. The molecular mechanism was determined using a luciferase reporter assay, ChIP assay, CAPTURE approach, and co-IP assay. FINDINGS: ZNF711 down-regulation exerts a great impact on CDDP resistance for EOC patients by suppressing SLC31A1 and inhibiting CDDP influx. ZNF711 down-regulation promoted, while ZNF711 overexpression drastically inhibited CDDP resistance, both in vivo and in vitro. Mechanistically, the histone demethylase JHDM2A was recruited to the SLC31A1 promoter by ZNF711 and decreased the H3K9me2 level, resulting in the activation of SLC31A1 transcription and enhancement of CDDP uptake. Importantly, co-treatment with the histone methylation inhibitor, BIX-01294, increased the therapeutic efficacy of CDDP treatment in ZNF711-suppressed EOC cells. INTERPRETATION: These findings both verified the clinical importance of ZNF711 in CDDP resistance and provide novel therapeutic regimens for EOC treatment. FUNDING: This work was supported by the Natural Science Foundation of China; Guangzhou Science and Technology Plan Projects; Natural Science Foundation of Guangdong Province; The Fundamental Research Funds for the Central Universities; and China Postdoctoral Science Foundation.

4.
Artigo em Inglês | MEDLINE | ID: mdl-34382418

RESUMO

AIMS: Acute myocardial infarction (MI), caused by acute coronary artery obstruction, is a common cardiovascular event leading to mortality. Nuclear dot protein 52 (NDP52) is an essential selective autophagy adaptor, although its function in MI is still obscure. This study was designed to examine the function of NDP52 in MI and the associated mechanisms. RESULTS: Our results revealed that MI challenge overtly impaired myocardial geometry and systolic function, along with cardiomyocyte apoptosis, myocardial interstitial fibrosis, and mitochondrial damage, and NDP52 nullified such devastating responses. Further studies showed the blockade of mitochondrial clearance is related to MI-induced buildup of damaged mitochondria. Mechanistic approaches depicted that 7-day MI induced abnormal mitophagy flux, resulting in poor lysosomal clearance of injured mitochondria. NDP52 promoted mitophagy flux through recruitment of RAB7 and TBK1. Upon protein colocalization, TBK1 phosphorylated RAB7, in line with the finding that chloroquine or a TBK1 inhibitor reversed NDP52-dependent beneficial responses. INNOVATION: This study denoted a novel mechanism that NDP52 promotes cardioprotection against ischemic heart diseases through interaction with TBK1 and RAB7, leading to RAB7 phosphorylation, induction of mitophagy to clear ischemia-induced impaired mitochondria, thus preventing cardiomyocyte apoptosis in MI. CONCLUSION: Our results indicate that NDP52 promotes autophagic flux and clears damaged mitochondria to diminish ROS and cell death in a TBK1/RAB7-dependent manner and thus limits MI induced injury.

5.
Metab Eng ; 67: 403-416, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34411702

RESUMO

Malonyl-CoA is an important building block for microbial synthesis of numerous pharmaceutically interesting or fatty acid-derived compounds including polyketides, flavonoids, phenylpropanoids and fatty acids. However, the tightly regulated intracellular malonyl-CoA availability often impedes overall product formation. Here, in order to unleash this tightly cellular behavior, we present evolution: dual dynamic regulations-based approaches to write artificial robust and dynamic function into intricate cellular background. Firstly, a conserved core domain based evolutionary principles were incorporated into genome mining to explore the biosynthetic diversities of discrete acetyl-CoA carboxylase (ACC) families, as malonyl-CoA is solely derived from carboxylation of acetyl-CoA by ACC in most organisms. A comprehensive phylogenomic and further experimental analysis, which included genomes of 50 strains throughout representative species, was performed to recapitulate the evolutionary history and reveal that previously unnoticed ACC families from Salmonella enterica exhibited the highest activities among all the candidates. A set of orthogonal and bi-functional quorum-sensing (QS)-based regulation tools were further designed and connected with T7 RNA polymerase as genetic amplifier to achieve dual dynamic control in a high dynamic range, which allowed us to efficiently activate and repress different sets of genes dynamically and independently. These genetic circuits were then combined with ACC of S. enterica and CRISPRi system to reprogram central metabolism that rewired the tightly regulated malonyl-CoA pathway to a robust and autonomous behavior, leading to a 29-fold increase of malony-CoA availability. We applied this dual regulation tool to successfully synthesizing malonyl-CoA-derived compound (2S)-naringenin, and achieved the highest production (1073.8 mg/L) reported to date associate with dramatic decreases of by-product formation. Notably, the whole fermentation presents as an autonomous behavior, totally eliminating human supervision and inducer supplementation. Hence, the constructed evolution: dual dynamic regulations-based approaches pave the way to develop an economically viable and scalable procedure for microbial production of malonyl-CoA derived compounds.

6.
Gigascience ; 10(8)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34414422

RESUMO

As the global health crisis unfolded, many academic conferences moved online in 2020. This move has been hailed as a positive step towards inclusivity in its attenuation of economic, physical, and legal barriers and effectively enabled many individuals from groups that have traditionally been underrepresented to join and participate. A number of studies have outlined how moving online made it possible to gather a more global community and has increased opportunities for individuals with various constraints, e.g., caregiving responsibilities. Yet, the mere existence of online conferences is no guarantee that everyone can attend and participate meaningfully. In fact, many elements of an online conference are still significant barriers to truly diverse participation: the tools used can be inaccessible for some individuals; the scheduling choices can favour some geographical locations; the set-up of the conference can provide more visibility to well-established researchers and reduce opportunities for early-career researchers. While acknowledging the benefits of an online setting, especially for individuals who have traditionally been underrepresented or excluded, we recognize that fostering social justice requires inclusivity to actively be centered in every aspect of online conference design. Here, we draw from the literature and from our own experiences to identify practices that purposefully encourage a diverse community to attend, participate in, and lead online conferences. Reflecting on how to design more inclusive online events is especially important as multiple scientific organizations have announced that they will continue offering an online version of their event when in-person conferences can resume.

7.
J Affect Disord ; 293: 466-475, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34256208

RESUMO

BACKGROUND: Posttraumatic stress disorder (PTSD) and depression are highly co-morbid among individuals with childhood abuse history, while the mechanism of the co-morbidity is highly debated. This study sought to extent the work among college students with network analysis, which is a novel method that sees the co-morbidity from a symptom interacting perspective. METHODS: Data was collected from 476 college students who were assessed to have childhood abuse history, PTSD and depression at the same time, using Childhood Trauma Questionnaire- Short Form, PTSD Checklist for DSM-5 and The Center for Epidemiological Studies Depression. We created a Graphical Gaussian Model (GGM) network to show associations between symptom pairs and a Directed Acyclic Graph (DAG) to estimate potential casual relationships among symptoms. RESULTS: The GGM network was reliably stable, feeling sad (Depression) and trouble experiencing positive feelings (PTSD) were the most central nodes. Trouble experiencing positive feelings and several negative affect symptoms, sleep problems and difficulty in concentrating were acting as important bridging nodes. The DAG network suggested the key triggering roles of exaggerated startle (PTSD) and several re-experiencing symptoms. LIMITATIONS: The study used cross-sectional data and self-reported measures. Results from network analysis could be affected by scale factors and contain spurious correlations. CONCLUSIONS: In the childhood-abuse-related co-morbid structure, several negative affect symptoms both in PTSD and depression have pivotal roles, hyper-arousal symptoms and re-experiencing symptoms could trigger the co-morbid structure. Illustrating the strength and limitations of network analysis, this study help target the potentially influential symptoms for better clinical intervention.


Assuntos
Maus-Tratos Infantis , Transtornos de Estresse Pós-Traumáticos , Criança , Estudos Transversais , Depressão , Humanos , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Estudantes
8.
J Biol Res (Thessalon) ; 28(1): 15, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34271975

RESUMO

E proteins are transcriptional regulators that regulate many developmental processes in animals and lymphocytosis and leukemia in Homo sapiens. In particular, E2A, a member of the E protein family, plays a major role in the transcriptional regulatory network that promotes the differentiation and development of B and T lymphocytes. E2A-mediated transcriptional regulation usually requires the formation of E2A dimers, which then bind to coregulators. In this review, we summarize the mechanisms by which E2A participates in transcriptional regulation from a structural perspective. More specifically, the C-terminal helix-loop-helix (HLH) region of the basic HLH (bHLH) domain first dimerizes, and then the activation domains of E2A bind to different coactivators or corepressors in different cell contexts, resulting in histone acetylation or deacetylation, respectively. Then, the N-terminal basic region (b) of the bHLH domain binds to or dissociates from a specific DNA motif (E-box sequence). Last, trans-activation or trans-repression occurs. We also summarize the properties of these E2A domains and their interactions with the domains of other proteins. The feasibility of developing drugs based on these domains is discussed.

9.
Trials ; 22(1): 425, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34187524

RESUMO

INTRODUCTION: In this report, we aim to describe the design for the randomised controlled trial of Stereotactic electroencephalogram (EEG)-guided Radiofrequency Thermocoagulation versus Anterior Temporal Lobectomy for Mesial Temporal Lobe Epilepsy with Hippocampal Sclerosis (STARTS). Mesial temporal lobe epilepsy (mTLE) is a classical subtype of temporal lobe epilepsy that often requires surgical intervention. Although anterior temporal lobectomy (ATL) remains the most popular treatment for mTLE, accumulating evidence has indicated that ATL can cause tetartanopia and memory impairments. Stereotactic EEG (SEEG)-guided radiofrequency thermocoagulation (RF-TC) is a non-invasive alternative associated with lower seizure freedom but greater preservation of neurological function. In the present study, we aim to compare the safety and efficacy of SEEG-guided RF-TC and classical ATL in the treatment of mTLE. METHODS AND ANALYSIS: STARTS is a single-centre, two-arm, randomised controlled, parallel-group clinical trial. The study includes patients with typical mTLE over the age of 14 who have drug-resistant seizures for at least 2 years and have been determined via detailed evaluation to be surgical candidates prior to randomisation. The primary outcome measure is the cognitive function at the 1-year follow-up after treatment. Seizure outcomes, visual field abnormalities after surgery, quality of life, ancillary outcomes, and adverse events will also be evaluated at 1-year follow-up as secondary outcomes. DISCUSSION: SEEG-guided RF-TC for mTLE remains a controversial seizure outcome but has the advantage for cognitive and visual field protection. This is the first RCT studying cognitive outcomes and treatment results between SEEG-guided RF-TC and standard ATL for mTLE with hippocampal sclerosis. This study may provide higher levels of clinical evidence for the treatment of mTLE. TRIAL REGISTRATION: ClinicalTrials.gov NCT03941613 . Registered on May 8, 2019. The STARTS protocol has been registered on the US National Institutes of Health. The status of the STARTS was recruiting and the estimated study completion date was December 31, 2021.


Assuntos
Epilepsia do Lobo Temporal , Lobectomia Temporal Anterior , Pré-Escolar , Eletrocoagulação/efeitos adversos , Eletroencefalografia , Epilepsia do Lobo Temporal/diagnóstico , Epilepsia do Lobo Temporal/patologia , Epilepsia do Lobo Temporal/cirurgia , Hipocampo/patologia , Hipocampo/cirurgia , Humanos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Esclerose/patologia , Resultado do Tratamento
10.
Cerebellum ; 2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34052968

RESUMO

The objective of this study was to identify the decussating dentato-rubro-thalamic tract (d-DRTT) and its afferent and efferent connections in healthy humans using diffusion spectrum imaging (DSI) techniques. In the present study, the trajectory and lateralization of the d-DRTT was explored using data from subjects in the Massachusetts General Hospital-Human Connectome Project adult diffusion dataset. The afferent and efferent networks that compose the cerebello-thalamo-cerebral pathways were also reconstructed. Correlation analysis was performed to identify interrelationships between subdivisions of the cerebello-dentato-rubro-thalamic and thalamo-cerebral connections. The d-DRTT was visualized bilaterally in 28 subjects. According to a normalized quantitative anisotropy and lateralization index evaluation, the left and right d-DRTT were relatively symmetric. Afferent regions were found mainly in the posterior cerebellum, especially the entire lobule VII (crus I, II and VIIb). Efferent fibers mainly are projected to the contralateral frontal cortex, including the motor and nonmotor regions. Correlations between cerebello-thalamic connections and thalamo-cerebral connections were positive, including the lobule VIIa (crus I and II) to the medial prefrontal cortex (MPFC) and the dorsolateral prefrontal cortex and lobules VI, VIIb, VIII, and IX, to the MPFC and motor and premotor areas. These results provide DSI-based tratographic evidence showing segregated and parallel cerebellar outputs to cerebral regions. The posterior cerebellum may play an important role in supporting and handling cognitive activities through d-DRTT. Future studies will allow for a more comprehensive understanding of cerebello-cerebral connections.

11.
Ultrasonics ; 115: 106417, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33964600

RESUMO

Synthetic aperture (SA) imaging can provide a uniform lateral resolution but an insufficient signal-to-noise ratio (SNR). SA method with bidirectional pixel-based focusing (SA-BiPBF) has the ability to obtain a higher quality image than conventional SA imaging. In this paper, an enhanced SA-BiPBF named full aperture received far-focused pixel-based (FrFPB) is firstly proposed to obtain a high resolution image. An adjustable zero-cross factor scaled Wiener postfilter (AZFsW) is then implemented in FrFPB for improving contrast ratio (CR). The adjustable zero-cross factor is calculated using the polarity of echo signals sequence with an adjustable coefficient σ to estimate the signal coherence, and it is combined with Wiener postfilter to obtain a good capability of noise reduction and background speckle pattern preservation. Simulation and experiments have been conducted to evaluate the imaging performance of the proposed methods. Results show that FrFPB can obviously improve the resolution in comparison with SA-BiPBF, and contrast-to-noise ratio (CNR) and speckle signal-to-noise ratio (sSNR) are retained. In addition, AZFsW can achieve a much higher CR than SA-BiPBF. When σ is 0.6, the CR improvement is 96.7% in simulation, 78.7% in phantom experiment, and 49.2% in in-vivo experiment. To evaluate the imaging performance of AZFsW, coherence factor, conventional Wiener postfilter, and scaled Wiener postfilter are implemented. The imaging results show that when σ is in the range of [0.6, 0.7], AZFsW exhibits a satisfying comprehensive imaging performance.

12.
Ultrasonics ; 114: 106423, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33798833

RESUMO

Compared with B-mode imaging, three-dimensional (3D) ultrasound imaging is more helpful in research and clinical application. At present, the 3D ultrasound images can be acquired directly with two-dimensional (2D) array transducer or reconstructed from a series of B-mode images obtained with one-dimensional (1D) array transducer. Imaging with 2D array transducer can achieve a high frame rate, but suffering from the complexity of the imaging system, such as the large amount of channels, and high computational complexity. Reconstructing 3D images from a series of B-mode images can be implemented by recording the position and orientation of the slice images. This is a low-cost and flexible imaging method, but usually suffering from the low imaging quality and low frame rate. In our previous work, a novel 3D ultrasound imaging method in frequency domain with a moved 1D array transducer is presented. This method can reduce the computational complexity with FFT, and get improved imaging quality and frame rate to some extent. Besides, this method can be adopted to construct images with a row-column-addressed 2D array, which can reduce the amount of channels effectively. In this paper, a two-steps implementation of this imaging method is proposed, in which the combined implementation of the 3D imaging is decomposed to two steps of 2D imaging processes in Frequency domain. In the first step, the received echoes of the 1D array transducer at each position are processed with a 2D imaging processes in the lateral- axial planes. In the second step, a 2D imaging processes is preformed in the planes of orthogonal to the transducer. Simulation results show that the two-steps implementation can achieve almost the same imaging quality to the previous work. Compared with the implementation of 3D imaging in our previous work, the proposed two-steps implementation can be carried out with parallel process to improve the computational efficiency, or carried out with loop to reduce the hardware cost. Besides, the first step can be performed with a conventional DAS imaging method when a cylindrical wave is adopted for imaging. The influence of the spread angle of the field is also discussed.

13.
J Mater Chem B ; 9(15): 3317-3325, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33666636

RESUMO

Multifunctional contrast-enhanced agents suitable for application in surgical navigation by taking advantage of the merits of their diverse imaging modalities at different surgical stages are highly sought-after. Herein, an amphipathic polymer composed of aggregation-induced emission fluorogens (AIEgens) and Gd3+ chelates was successfully synthesized and assembled into ultrasound responsive microbubbles (AIE-Gd MBs) to realize potential tri-modal contrast-enhanced ultrasound (US) imaging, magnetic resonance imaging (MRI), and AIEgen-based fluorescence imaging (FI) during the perioperative period. Through ultrasound targeted microbubble destruction (UTMD) and cavitation effect, the as-prepared AIE-Gd MBs went through a MBs-to-nanoparticles (NPs) conversion, which not only resulted in targeted accumulation in tumor tissues but also led to stronger fluorescence being exhibited due to the more aggregated AIE-Gd molecules in the NPs. As a proof-of-concept, our work proposes a strategy of US-lit-up AIEgens in tumors which could offer a simple and powerful tool for surgical navigation in the future.


Assuntos
Meios de Contraste/química , Corantes Fluorescentes/química , Imagem Óptica , Polímeros/química , Cirurgia Assistida por Computador , Ultrassonografia , Meios de Contraste/síntese química , Corantes Fluorescentes/síntese química , Humanos
14.
Exp Biol Med (Maywood) ; 246(1): 72-83, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32941074

RESUMO

IMPACT STATEMENT: Nasopharyngeal cancer is one of the most common malignant tumors in the head and neck. Identification of promising miRNA biomarkers might benefit a lot to the detection of nasopharyngeal carcinoma. A three-miRNA signature (has-miR-142-3p, has-miR-29c, and has-miR-30e) was obviously associated with the overall survival of nasopharyngeal carcinoma patients. The model has better clinical independence and has better clinical prediction effect when combined with clinical characteristics. Our results revealed that a three-miRNA signature was a potential novel prognostic biomarker for nasopharyngeal carcinoma.


Assuntos
Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias Nasofaríngeas/genética , Área Sob a Curva , Humanos , Estimativa de Kaplan-Meier , MicroRNAs/metabolismo , Neoplasias Nasofaríngeas/patologia , Prognóstico , Reprodutibilidade dos Testes
15.
Acta Pharmacol Sin ; 42(3): 404-413, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32317756

RESUMO

In patients with sepsis, lipopolysaccharide (LPS) from the outer membrane of gram-negative bacteria triggers cardiac dysfunction and heart failure, but target therapy for septic cardiomyopathy remains unavailable. In this study we evaluated the beneficial effects of cardamonin (CAR), a flavone existing in Alpinia plant, on endotoxemia-induced cardiac dysfunction and the underlying mechanisms with focus on oxidative stress and apoptosis. Adult mice were exposed to LPS (4 mg/kg, i.p. for 6 h) prior to functional or biochemical assessments. CAR (20 mg/kg, p.o.) was administered to mice immediately prior to LPS challenge. We found that LPS challenge compromised cardiac contractile function, evidenced by compromised fractional shortening, peak shortening, maximal velocity of shortening/relengthening, enlarged LV end systolic diameter and prolonged relengthening in echocardiography, and induced apoptosis, overt oxidative stress (O2- production and reduced antioxidant defense) associated with inflammation, phosphorylation of NF-κB and cytosolic translocation of transcriptional factor Nrf2. These deteriorative effects were greatly attenuated or mitigated by CAR administration. However, H&E and Masson's trichrome staining analysis revealed that neither LPS challenge nor CAR administration significantly affected cardiomyocyte cross-sectional area and interstitial fibrosis. Mouse cardiomyocytes were treated with LPS (4 µg/mL) for 6 h in the absence or presence of CAR (10 µM) in vitro. We found that addition of CAR suppressed LPS-induced defect in cardiomyocyte shortening, which was nullified by the Nrf2 inhibitor ML-385 or the NF-κB activator prostratin. Taken together, our results suggest that CAR administration protects against LPS-induced cardiac contractile abnormality, oxidative stress, apoptosis, and inflammation through Nrf2- and NF-κB-dependent mechanism.

16.
Artigo em Inglês | MEDLINE | ID: mdl-33141664

RESUMO

The delay-and-sum (DAS) beamformer is the most commonly used method in medical ultrasound imaging. Compared with the DAS beamformer, the minimum variance (MV) beamformer has an excellent ability to improve lateral resolution by minimizing the output of interference and noise power. However, it is hard to overcome the tradeoff between satisfactory lateral resolution and speckle preservation performance due to the fixed subarray length of covariance matrix estimation. In this study, a new approach for MV beamforming with adaptive spatial smoothing is developed to address this problem. In the new approach, the generalized coherence factor (GCF) is used as a local coherence detection tool to adaptively determine the subarray length for spatial smoothing, which is called adaptive spatial-smoothed MV (AMV). Furthermore, another adaptive regional weighting strategy based on the local signal-to-noise ratio (SNR) and GCF is devised for AMV to enhance the image contrast, which is called GCF regional weighted AMV (GAMV). To evaluate the performance of the proposed methods, we compare them with the standard MV by conducting the simulation, in vitro experiment, and the in vivo rat mammary tumor study. The results show that the proposed methods outperform MV in speckle preservation without an appreciable loss in lateral resolution. Moreover, GAMV offers excellent performance in image contrast. In particular, AMV can achieve maximal improvements of speckle signal-to-noise ratio (SNR) by 96.19% (simulation) and 62.82% (in vitro) compared with MV. GAMV achieves improvements of contrast-to-noise ratio by 27.16% (simulation) and 47.47% (in vitro) compared with GCF. Meanwhile, the losses in lateral resolution of AMV are 0.01 mm (simulation) and 0.17 mm (in vitro) compared with MV. Overall, this indicates that the proposed methods can effectively address the inherent limitation of the standard MV in order to improve the image quality.

17.
Psychother Psychosom ; 90(2): 127-136, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33152729

RESUMO

BACKGROUND: As the fight against the COVID-19 epidemic continues, medical workers may have allostatic load. OBJECTIVE: During the reopening of society, medical and nonmedical workers were compared in terms of allostatic load. METHODS: An online study was performed; 3,590 Chinese subjects were analyzed. Socio-demographic variables, allostatic load, stress, abnormal illness behavior, global well-being, mental status, and social support were assessed. RESULTS: There was no difference in allostatic load in medical workers compared to nonmedical workers (15.8 vs. 17.8%; p = 0.22). Multivariate conditional logistic regression revealed that anxiety (OR = 1.24; 95% CI 1.18-1.31; p < 0.01), depression (OR = 1.23; 95% CI 1.17-1.29; p < 0.01), somatization (OR = 1.20; 95% CI 1.14-1.25; p < 0.01), hostility (OR = 1.24; 95% CI 1.18-1.30; p < 0.01), and abnormal illness behavior (OR = 1.49; 95% CI 1.34-1.66; p < 0.01) were positively associated with allostatic load, while objective support (OR = 0.84; 95% CI 0.78-0.89; p < 0.01), subjective support (OR = 0.84; 95% CI 0.80-0.88; p < 0.01), utilization of support (OR = 0.80; 95% CI 0.72-0.88; p < 0.01), social support (OR = 0.90; 95% CI 0.87-0.93; p < 0.01), and global well-being (OR = 0.30; 95% CI 0.22-0.41; p < 0.01) were negatively associated. CONCLUSIONS: In the post-COVID-19 epidemic time, medical and nonmedical workers had similar allostatic load. Psychological distress and abnormal illness behavior were risk factors for it, while social support could relieve it.


Assuntos
Alostase/fisiologia , Ansiedade/fisiopatologia , COVID-19 , Depressão/fisiopatologia , Pessoal de Saúde , Comportamento de Doença/fisiologia , Satisfação Pessoal , Apoio Social , Estresse Psicológico/fisiopatologia , Adulto , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ocupações
18.
J Urol ; 205(4): 1090-1099, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33315505

RESUMO

PURPOSE: We determined the early efficacy of bipolar radiofrequency ablation with a coil design for focal ablation of clinically significant localized prostate cancer visible at multiparametric magnetic resonance imaging. MATERIALS AND METHODS: A prospective IDEAL phase 2 development study (Focal Prostate Radiofrequency Ablation, NCT02294903) recruited treatment-naïve patients with a single focus of significant localized prostate cancer (Gleason 7 or 4 mm or more of Gleason 6) concordant with a lesion visible on multiparametric magnetic resonance imaging. Intervention was a focal ablation with a bipolar radiofrequency system (Encage™) encompassing the lesion and a predefined margin using nonrigid magnetic resonance imaging-ultrasound fusion. Primary outcome was the proportion of men with absence of significant localized disease on biopsy at 6 months. Trial followup consisted of serum prostate specific antigen, multiparametric magnetic resonance imaging at 1 week, and 6 and 12 months post-ablation. Validated patient reported outcome measures for urinary, erectile and bowel functions, and adverse events monitoring system were used. Analyses were done on a per-protocol basis. RESULTS: Of 21 patients recruited 20 received the intervention. Baseline characteristics were median age 66 years (IQR 63-69) and preoperative median prostate specific antigen 7.9 ng/ml (5.3-9.6). A total of 18 patients (90%) had Gleason 7 disease with median maximum cancer 7 mm (IQR 5-10), for a median of 2.8 cc multiparametric magnetic resonance imaging lesions (IQR 1.4-4.8). Targeted biopsy of the treated area (median number of cores 6, IQR 5-8) showed absence of significant localized prostate cancer in 16/20 men (80%), concordant with multiparametric magnetic resonance imaging. There was a low profile of side effects at patient reported outcome measures analysis and there were no serious adverse events. CONCLUSIONS: Focal therapy of significant localized prostate cancer associated with a magnetic resonance imaging lesion using bipolar radiofrequency showed early efficacy to ablate cancer with low rates of genitourinary and rectal side effects.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Ablação por Radiofrequência/instrumentação , Idoso , Biomarcadores Tumorais/sangue , Biópsia , Desenho de Equipamento , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/patologia
19.
ACS Appl Mater Interfaces ; 12(46): 51344-51356, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33146507

RESUMO

Thin-film lithium-ion microbatteries with a high energy density and long lifespan are exceedingly desired for developing self-powered integrated micro-nano devices and systems. However, exploring high-performance thin-film anodes still remains a challenge. Herein, a double-layer-structure diamond-like carbon-ZnS (DLC-ZnS) thin-film anode fabricated by radio frequency magnetron sputtering exhibits high specific capacity and good cycling stability up to 1000 cycles, superior to the pure ZnS thin-film anode. To understand the mechanism, the bimodal amplitude modulated-frequency modulated atomic force microscopy was used to explore the mechanical properties of the thin films, and the DLC layer shows significantly higher Young's modulus than the ZnS thin film. The DLC interface with a high Young's modulus can effectively buffer the mechanical stress originating from the huge volume changes of the ZnS layer during lithiation/delithiation processes; therefore, the DLC interface maintains the higher mechanical integrity of the DLC-ZnS thin film and improves the utilization of ZnS. In addition, the electrochemical kinetics of the DLC-ZnS and ZnS thin films were also investigated by electrochemical methods. Electrochemical impedance spectroscopy tests indicate the obstacle of the DLC interface to Li+ ion diffusion in the initial charge/discharge processes; however, the DLC-ZnS thin film exhibits lower total resistance than the ZnS thin film afterward. In particular, galvanostatic intermittent titration technique tests were performed to find out the differences between the two thin films during the galvanostatical charge/discharge processes. The results demonstrate the obviously enhanced conversion reaction reversibility and decreased alloy reaction polarization of the DLC-ZnS thin film; therefore, it delivers higher reversible capacity.

20.
Cogn Affect Behav Neurosci ; 20(6): 1200-1215, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33089442

RESUMO

During the past two decades, cognitive neuroscientists have sought to elucidate the common neural basis of the experience of beauty. Still, empirical evidence for such common neural basis of different forms of beauty is not conclusive. To address this question, we performed an activation likelihood estimation (ALE) meta-analysis on the existing neuroimaging studies of beauty appreciation of faces and visual art by nonexpert adults (49 studies, 982 participants, meta-data are available at https://osf.io/s9xds/ ). We observed that perceiving these two forms of beauty activated distinct brain regions: While the beauty of faces convergently activated the left ventral striatum, the beauty of visual art convergently activated the anterior medial prefrontal cortex (aMPFC). However, a conjunction analysis failed to reveal any common brain regions for the beauty of visual art and faces. The implications of these results are discussed.

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