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1.
Biomed Opt Express ; 12(10): 5991-6012, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34745717

RESUMO

Fluorescence molecular tomography (FMT), which is used to visualize the three-dimensional distribution of fluorescence probe in small animals via the reconstruction method, has become a promising imaging technique in preclinical research. However, the classical reconstruction criterion is formulated based on the squared l 2-norm distance metric, leaving it prone to being influenced by the presence of outliers. In this study, we propose a robust distance based on the correntropy-induced metric with a Laplacian kernel (CIML). The proposed metric satisfies the conditions of distance metric function and contains first and higher order moments of samples. Moreover, we demonstrate important properties of the proposed metric such as nonnegativity, nonconvexity, and boundedness, and analyze its robustness from the perspective of M-estimation. The proposed metric includes and extends the traditional metrics such as l 0-norm and l 1-norm metrics by setting an appropriate parameter. We show that, in reconstruction, the metric is a sparsity-promoting penalty. To reduce the negative effects of noise and outliers, a novel robust reconstruction framework is presented with the proposed correntropy-based metric. The proposed CIML model retains the advantages of the traditional model and promotes robustness. However, the nonconvexity of the proposed metric renders the CIML model difficult to optimize. Furthermore, an effective iterative algorithm for the CIML model is designed, and we present a theoretical analysis of its ability to converge. Numerical simulation and in vivo mouse experiments were conducted to evaluate the CIML method's performance. The experimental results show that the proposed method achieved more accurate fluorescent target reconstruction than the state-of-the-art methods in most cases, which illustrates the feasibility and robustness of the CIML method.

2.
Front Oncol ; 11: 751055, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745977

RESUMO

Cerenkov luminescence tomography (CLT) is a promising non-invasive optical imaging method with three-dimensional semiquantitative in vivo imaging capability. However, CLT itself relies on Cerenkov radiation, a low-intensity radiation, making CLT reconstruction more challenging than other imaging modalities. In order to solve the ill-posed inverse problem of CLT imaging, some numerical optimization or regularization methods need to be applied. However, in commonly used methods for solving inverse problems, parameter selection significantly influences the results. Therefore, this paper proposed a probabilistic energy distribution density region scaling (P-EDDRS) framework. In this framework, multiple reconstruction iterations are performed, and the Cerenkov source distribution of each reconstruction is treated as random variables. According to the spatial energy distribution density, the new region of interest (ROI) is solved. The size of the region required for the next operation was determined dynamically by combining the intensity characteristics. In addition, each reconstruction source distribution is given a probability weight value, and the prior probability in the subsequent reconstruction is refreshed. Last, all the reconstruction source distributions are weighted with the corresponding probability weights to get the final Cerenkov source distribution. To evaluate the performance of the P-EDDRS framework in CLT, this article performed numerical simulation, in vivo pseudotumor model mouse experiment, and breast cancer mouse experiment. Experimental results show that this reconstruction framework has better positioning accuracy and shape recovery ability and can optimize the reconstruction effect of multiple algorithms on CLT.

3.
Sensors (Basel) ; 21(21)2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34770726

RESUMO

In terms of small objects in traffic scenes, general object detection algorithms have low detection accuracy, high model complexity, and slow detection speed. To solve the above problems, an improved algorithm (named YOLO-MXANet) is proposed in this paper. Complete-Intersection over Union (CIoU) is utilized to improve loss function for promoting the positioning accuracy of the small object. In order to reduce the complexity of the model, we present a lightweight yet powerful backbone network (named SA-MobileNeXt) that incorporates channel and spatial attention. Our approach can extract expressive features more effectively by applying the Shuffle Channel and Spatial Attention (SCSA) module into the SandGlass Block (SGBlock) module while increasing the parameters by a small number. In addition, the data enhancement method combining Mosaic and Mixup is employed to improve the robustness of the training model. The Multi-scale Feature Enhancement Fusion (MFEF) network is proposed to fuse the extracted features better. In addition, the SiLU activation function is utilized to optimize the Convolution-Batchnorm-Leaky ReLU (CBL) module and the SGBlock module to accelerate the convergence of the model. The ablation experiments on the KITTI dataset show that each improved method is effective. The improved algorithm reduces the complexity and detection speed of the model while improving the object detection accuracy. The comparative experiments on the KITTY dataset and CCTSDB dataset with other algorithms show that our algorithm also has certain advantages.


Assuntos
Algoritmos , Projetos de Pesquisa
4.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 37(6): 577-583, 2021 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-34821087

RESUMO

Objective: To study the role of Notch-1/Twist-1 axis in the process of epithelial-mesenchymal transition (EMT) of type II alveolar epithelial cells in pulmonary fibrosis (PF) and hope to provide a new theoretical basis for the pathogenesis of PF. Methods: Thirty rats were randomly divided into control group and bleomycin (BLM) group, 15 rats in each group. The PF rat model was induced by intratracheal injection of BLM (7 500 U/kg). Excised inferior lobe of left lung was fixed in 10% formalin for HE staining, Masson staining and transforming growth factor-beta 1 (TGF-ß1) immunohistochemistry staining after BLM injection for 28 days. The cultured type II alveolar epithelial cells (RLE-6TN) were divided into 4 groups (Control group, transforming growth factor-beta 1 (TGF-ß1) group, Notch-1 negative control siRNA (NC siRNA, 100 pmol/L) group and Notch-1 siRNA (100 pmol/L) group), each group was established nine holes. The cells were treated with TGF-ß1 (5.0 ng/ml) for 24 h following NC siRNA or Notch-1 siRNA for 48 h. The mRNA and (or) proteins levels of TGF-ß1, collagen I, collagen III, E-Cadherin, zonula occludens-1 (ZO-1), Vimentin, E-Cadherin, Notch-1, Notch-1 intracellular domain (NICD), Hes-1 and Twist-1 were detected in lung tissue and type II alveolar epithelial cells. Results: In vivo, compared with the control group, the alveolar atrophy, collapse and fusion occurred, alveolar septum widened significantly, and a large number of inflammatory cells infiltrated in the pulmonary interstitial of the rats in the BLM group. And compared with control group, BLM obviously increased collagen deposition and collagen I and collagen III expressions, while the expressions of ZO-1 and E-cadherin were decreased, and the expressions of Vimentin and N-cadherin were increased, and concomitantly with increasing Notch-1, NICD, Hes-1 and Twist-1 expression in lung tissues of rats (P<0.01). In vitro, compared with control group, TGF-ß1 treatment obviously induced collagen I, collagen III, Notch-1, NICD, Hes-1 and Twist-1 expressions, and the expressions of E-cadherin and ZO-1 were decreased and the expressions of Vimentin and N-cadherin were increased(P<0.01). Compared with TGF-ß1 group, Notch-1 siRNA treatment significantly inhibited the expressions of Notch-1, NICD, Hes-1 and Twist-1, and the expressions of E-cadherin and ZO-1 were increased and the expressions of Vimentin and N-cadherin were decreased, and also obviously reduced the expressions of collagen I and collagen III induced by TGF-ß1 (P<0.05 or P<0.01). Conclusion: Notch-1/Twist-1 axis is involved in the EMT process of type II alveolar epithelial cells, suggesting that Notch-1/Twist-1 signaling may be involved in the development of pulmonary fibrosis.


Assuntos
Transição Epitelial-Mesenquimal , Fibrose Pulmonar , Células Epiteliais Alveolares , Animais , Bleomicina , Pulmão , Fibrose Pulmonar/induzido quimicamente , Ratos , Fator de Crescimento Transformador beta1
5.
Front Oncol ; 11: 749889, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34631587

RESUMO

Cerenkov luminescence tomography (CLT) has attracted much attention because of the wide clinically-used probes and three-dimensional (3D) quantification ability. However, due to the serious morbidity of 3D optical imaging, the reconstructed images of CLT are not appreciable, especially when single-view measurements are used. Single-view CLT improves the efficiency of data acquisition. It is much consistent with the actual imaging environment of using commercial imaging system, but bringing the problem that the reconstructed results will be closer to the animal surface on the side where the single-view image is collected. To avoid this problem to the greatest extent possible, we proposed a prior compensation algorithm for CLT reconstruction based on depth calibration strategy. This method takes full account of the fact that the attenuation of light in the tissue will depend heavily on the depth of the light source as well as the distance between the light source and the detection plane. Based on this consideration, a depth calibration matrix was designed to calibrate the attenuation between the surface light flux and the density of the internal light source. The feature of the algorithm was that the depth calibration matrix directly acts on the system matrix of CLT reconstruction, rather than modifying the regularization penalty items. The validity and effectiveness of the proposed algorithm were evaluated with a numerical simulation and a mouse-based experiment, whose results illustrated that it located the radiation sources accurately by using single-view measurements.

6.
Sci Total Environ ; 807(Pt 2): 150792, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34619192

RESUMO

Owing to the implementation of air pollution control actions, anthropogenic emissions in Beijing have changed in recent years. Understanding the impact of changes in anthropogenic emissions on O3 and PM2.5 trends is helpful for developing air quality management strategies. Herein, we investigated the variations of air pollutants in summer over Beijing using long-term data sets from 2014 to 2019, and explored the responses of O3 and PM2.5 trends to changes in anthropogenic emissions based on multiple linear regression (MLR) analysis and WRF-Chem model. The results indicated a significant decrease in PM2.5, but a near constant level of O3 during 2014-2019. The decrease rate of PM2.5, which was lower than that of SO2, might be due to the effect of NO2 on atmospheric PM2.5. Both the slightly increasing correlations between PM2.5 and NO2 and the WRF-Chem model simulations implied that atmospheric PM2.5 in Beijing is trending to be more sensitive to NOx than SO2. The emissions of NOx and VOCs from industry and transportation were found to make great contribution to O3 production in Beijing. Due to the titration of NOx in VOC-limited regime, the relatively low emission ratios of NOx and VOCs from industry and transportation in Beijing provided convincing evidence for the persistently high O3 concentrations during 2014-2019. However, the noticeable increase of the O3 trends in other areas (e.g., Hebei, Tianjin) could be explained by the significant decline in the emission ratios of NOx and VOCs from anthropogenic emissions especially industry during 2014-2019. Controlling the emission of NOx can substantially reduce PM2.5 pollution, but may aggravate O3 pollution, and thus effective VOC emission control strategies need to be considered for simultaneously controlling O3 and PM2.5 pollution in Beijing and other regions of China.

7.
J Immunol Res ; 2021: 6666428, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34514001

RESUMO

Liver ischemia-reperfusion injury (IRI) is an inevitable process during liver transplantation, hemorrhagic shock, resection, and other liver surgeries. It is an important cause of postoperative liver dysfunction and increased medical costs. The protective effects of the vagus nerve on hepatic IRI have been reported, but the underlying mechanism has not been fully understood. We established a hepatic vagotomy (Hv) mouse model to study the effect of the vagus on liver IRI and to explore the underlying mechanism. Liver IRI was more serious in mice with Hv, which showed higher serum ALT and AST activities and histopathological changes. Further experiments confirmed that Hv significantly downregulated the expression of IL-22 protein and mRNA in the liver, blocking the activation of the STAT3 pathway. The STAT3 pathway in the livers of Hv mice was significantly activated, and liver injury was clearly alleviated after treatment with exogenous IL-22 recombinant protein. In conclusion, Hv can aggravate hepatic IRI, and its mechanism may be related to inhibition of IL-22 expression and downregulation of the STAT3 pathway in the liver.

8.
Phys Med Biol ; 66(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34492648

RESUMO

Objective. X-ray luminescence computed tomography (XLCT) has played a crucial role in pre-clinical research and effective diagnosis of disease. However, due to the ill-posed of the XLCT inverse problem, the generalization of reconstruction methods and the selection of appropriate regularization parameters are still challenging in practical applications. In this research, an robust Elastic net-ℓ1ℓ2reconstruction method is proposed aiming to the challenge.Approach. Firstly, our approach consists of ℓ1and ℓ2regularization to enhance the sparsity and suppress the smoothness. Secondly, through optimal approximation of the optimization problem, double modification of Landweber algorithm is adopted to solve the Elastic net-ℓ1ℓ2regulazation. Thirdly, drawing on the ideal of supervised learning, multi-parameter K-fold cross validation strategy is proposed to determin the optimal parameters adaptively.Main results. To evaluate the performance of the Elastic net-ℓ1ℓ2method, numerical simulations, phantom and in vivo experiments were conducted. In these experiments, the Elastic net-ℓ1ℓ2method achieved the minimum reconstruction error (with smallest location error, fluorescent yield relative error, normalized root-mean-square error) and the best image reconstruction quality (with largest contrast-to-noise ratio and Dice similarity) among all methods. The results demonstrated that Elastic net-ℓ1ℓ2can obtain superior reconstruction performance in terms of location accuracy, dual source resolution, robustness and in vivo practicability.Significance. It is believed that this study will further benefit preclinical applications with a view to provide a more reliable reference for the later researches on XLCT.

9.
J Opt Soc Am A Opt Image Sci Vis ; 38(7): 985-991, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34263754

RESUMO

X-ray luminescence computed tomography (XLCT) has become an emerging hybrid molecular imaging technology with high detection sensitivity and low cost. However, the inverse problem of reconstruction has severe ill-posed consequences. The original regularization algorithm needs to take much time to solve the problem. To reduce the cost of time, a three-term conjugate gradient (TTCG) algorithm is proposed for XLCT. Useful truncation information is added to the descent direction to find the optimal solution quickly in our proposed algorithm. Both numerical simulation experiments and real experiments are carried out to verify the performance of the algorithm. Experimental results show that the presented algorithm can effectively speed up the reconstruction process.

11.
J Colloid Interface Sci ; 604: 616-623, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34280759

RESUMO

High-performance microwave absorption absorbers play important roles in the fields of radar stealth, electromagnetic protection, and antenna technology. In this work, high aspect-ratio Ag nanowires were decorated with magnetic CoNi nanoparticles via a PVP-induced solvothermal method, and then amorphous Sn(OH)2/SnO2 shells were introduced through an in-situ oxidative hydrolysis method, successfully preparing Ag-CoNi@Sn(OH)2/SnO2 composites. The morphology and ingredient of composites were ascertained by SEM, TEM, XRD, EDX, and XPS. As Ag-CoNi nanocomposites are coated by Sn(OH)2/SnO2 shells, the minimum reflection loss value is decreased from -31.7 dB (10.1 GHz) to -37.8 dB (6.4 GHz), and the maximum effective absorption bandwidth is extended from 3.9 GHz (10.3-14.2 GHz) to 5.8 GHz (10.7-16.5 GHz). Analyses of electromagnetic parameters reveal the possible mechanisms, involving surface plasma resonance, conductive loss, interfacial polarization, dipole polarization, exchange resonance, eddy current effect, multiple reflection and scattering. Thus, Ag nanowires modified with CoNi nanoparticles and amorphous Sn(OH)2/SnO2 shells can effectively balance the impedance matching and attenuation capability. It is a new strategy to achieve broadband microwave absorbers.

12.
Sci Total Environ ; 783: 146867, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34088120

RESUMO

Atmospheric non-methane hydrocarbons (NMHCs) were measured synchronously at an urban site of Beijing city (BJ) and a rural site of Dongbaituo (DBT) in Hebei province from 1 July to 15 August 2016. The average concentration of the total NMHCs (TNMHCs) at DBT site were about a factor of 1.3 higher than that at BJ site. Ethane, ethylene, propane, acetylene, butane, isobutane, toluene and isopentane were the common species in the top ten NMHCs at the two sampling sites, and the contributions of the top ten NMHCs to TNMHCs at BJ and DBT sites were 65.6% and 75.1%, respectively. The diurnal variations of TNMHCs at BJ site exhibited one peak during the morning rush hours, whereas two peaks occurred at DBT site during the period from 3:00 to 8:00 (UTC/GMTC8). Based on the correlation coefficients of typical NMHCs pairs and the positive matrix factorization (PMF) results, the gasoline exhaust was found to be the dominant source (38.8%) for atmospheric NMHCs in Beijing, while coal combustion made the largest contribution (32.3%) at the rural site. Atmospheric ozone production over the BJ site was found to be NMHCs-sensitive, while it was in the transition regime at DBT site. Additionally, the largest contributions of atmospheric NMHCs groups to the ozone formation potential at BJ and DBT sites were alkenes and aromatics, with the proportions of 35.8% and 38.6%, respectively.

13.
Environ Pollut ; 285: 117444, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34090068

RESUMO

Volatile organic compounds (VOCs) are easily degraded by oxidants during atmospheric transport. Therefore, the contribution of VOCs to ozone (O3) and secondary organic aerosol (SOA) formation at a receptor site is different from that in a source area. In this study, hourly concentrations of VOCs and other pollutants, such as O3, NOx, HONO, CO, and PM2.5, were measured in the suburbs (Daxing district) of Beijing in August 2019. The photochemical initial concentrations (PICs), in which the photochemical losses of VOCs were accounted for, were calculated to evaluate the contribution of the VOCs to O3 and SOA formation. The mean (±standard deviation) measured VOC concentrations and the PICs were 11.2 ± 5.7 and 14.6 ± 8.4 ppbv, respectively, which correspond to O3 formation potentials (OFP) of 57.8 ± 26.3 and 103.9 ± 109.4 ppbv and SOA formation potentials (SOAP) of 8.4 ± 4.1 and 10.3 ± 7.4 µg m-3, respectively. Alkenes contributed 80.5% of the consumed VOCs, followed by aromatics (13.3%) and alkanes (6.2%). The contributions of the alkenes and aromatics to the OFPPICs were 56.8% and 30.3%, respectively; while their corresponding contributions to the SOAPPICs were 1.9% and 97.3%, respectively. The OFPPICs was linearly correlated with the observed O3 concentrations (OFPPICs = 41.5 + 1.40 × cO3, R2 = 0.87). The O3 formation was associated with a VOC-limited regime at the receptor site based on the measured VOCs and changed to a transition regime and a NOx sensitive regime based on the PIC. Our results suggest that more attention should be paid to biogenic VOCs when studying O3 formation in summer in Beijing, while the control of anthropogenic aromatic compounds should be given priority in terms of SOA formation.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Aerossóis/análise , Poluentes Atmosféricos/análise , Pequim , China , Monitoramento Ambiental , Ozônio/análise , Compostos Orgânicos Voláteis/análise
14.
Ann Palliat Med ; 10(6): 6892-6899, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34154364

RESUMO

BACKGROUND: As the last resort in intensive care units, physical restraint reduction is affected by various interventions. Several non-pharmacological interventions may directly reduce physical restraints, such as staff education, or indirectly reduce physical restraint, such as delirium prevention; however, their effectiveness has remained inconclusive. Therefore, we devised a protocol for umbrella reviews to summarize the evidence integrating data of different non-pharmacological interventions that may reduce physical restraint use. METHODS: The umbrella review will be conducted following the methodology formulated by the Joanna Briggs Institute (JBI). Electronic databases, including Web of Science, PubMed, EMBASE, PsycInfo, Psyc Articles, Psychology and Behavioral Science Collection, Cumulative Index to Nursing and Allied Health Literature (CINAHL), JBISRIS (JBI Database of Systematic Reviews and Implementation Reports), Cochrane Database of Systematic Reviews, China National Knowledge Infrastructure (CNKI, for Chinese literature), SinoMed (for Chinese literature), and WANFANG DATA (for Chinese literature), will be searched to identify articles published from January 2016 to December 2020. A systematic review and meta-analysis quality will be critically assessed by AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews). According to the GRADE (Grades of Recommendation, Assessment, Development, and Evaluation) guidelines, the evidence quality of each intervention will be assessed. Overlapping studies and the excess significance test will be performed to assess whether previous evidences are bias. DISCUSSION: This protocol was devised according to the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P). Umbrella reviews will be an excellent supplement to the evidence of the guideline adaptation and provide a broader picture of non-pharmacological interventions that may reduce the use of physical restraint, which can provide critical care nurses in intensive care units with the evidence they need. TRIAL REGISTRATION: This umbrella review protocol was documented in the PROSPERO registry (CRD42021242586).


Assuntos
Unidades de Terapia Intensiva , Restrição Física , China , Humanos , Metanálise como Assunto , Literatura de Revisão como Assunto , Revisões Sistemáticas como Assunto
15.
J Biophotonics ; 14(11): e202100089, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34176239

RESUMO

X-ray luminescence computed tomography (XLCT) uses external X-rays for luminescence excitation, which is becoming a promising molecular imaging technique with superb penetration depth and spatial resolution. To achieve the tomographic mapping of luminescence distribution, accurate optical propagation model and suitable reconstruction method are two keys for XLCT, but not satisfied. To overcome the limitation of the single proton propagation model (e.g., DE, SP3 ), we adopted a hybrid diffusion equation with third order simplified spherical harmonics (DE-SP3 ) model for XLCT. To enable fast iteration and accurate sparse reconstruction, we also integrated in the inversion optimization, with a novel Least Square QR-factorization based on the Lasso (Lasso-LSQR) algorithm. We first simulated the light propagation in various kinds of organs under DE model and SP3 model, respectively. By comparison with the Monte Carlo, these tissues can be categorized into two types, namely DE-fitted tissues that include muscle and lung, and SP3 -fitted tissues including heart, kidney, liver, and stomach. According to the above classification results, we built a hybrid DE-SP3 model to more accurately describing light transport. Numerical simulations and in vivo experiments illustrated that hybrid DE-SP3 model achieves superior reconstruction performance in terms of location accuracy, and spatial resolution than DE, and less computational cost than SP3 . The hybrid DE-SP3 model materializes a balance between accuracy and efficiency for XLCT.

16.
Med Phys ; 48(7): 3804-3814, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33969487

RESUMO

PURPOSE: Vessel segmentation from volumetric medical images is becoming an essential pre-step in aiding the diagnosis, guiding the therapy, and patient management for vascular-related diseases. Deep learning-based methods have drawn many attentions, but most of them did not fully utilize the multi-scale spatial information of vessels. To address this shortcoming, we propose a multi-scale network similar to the well-known multi-scale DeepMedic. It also includes a double-pathway architecture and a class-balanced loss at the voxel level (MDNet-Vb) to achieve both the computation efficiency and segmentation accuracy. METHODS: The proposed network consists two parallel pathways to learn the multi-scale vessel morphology. Specifically, the pathway with a normal resolution uses three-dimensional (3D) U-Net fed with small inputs to learn the local details with relatively small storage and time consumption. The pathway with a low-resolution employs 3D fully convolutional network (FCN) fed with downsampled large inputs to learn the overall spatial relationships between vessels and adjacent tissues, and the morphological information of large vessels. To cope with the class-imbalanced issue in vessel segmentation, we propose a class-balanced loss at the voxel level with uniform sampling strategy. The class-balanced loss at the voxel level re-balances the loss function with a coefficient that is inversely proportional to the normalized effective number at the voxel level of each class. The uniform sampling strategy extracts training data by sampling uniformly from two classes in every epoch. RESULTS: Our MDNet-Vb outperforms several state-of-the-art methods including ResNet, DenseNet, 3D U-Net, V-Net, and DeepMedic with the highest dice coefficients of 72.91% and 69.32% on cardiac computed tomography angiography (CTA) dataset and cerebral magnetic resonance angiography (MRA) dataset, respectively. Among four different double-pathway networks, our network (3D U-Net+3D FCN) not only has the fewest training parameters and shortest training time, but also gets competitive dice coefficients on both the CTA and MRA datasets. Compared with classical losses, our class-balanced focal loss (FL-Vb) and dice coefficient loss at the voxel level (Dsc-Vb) alleviates class imbalanced issue by improving both the sensitivity and dice coefficient on the CTA and MRA datasets. Moreover, simultaneously training on two datasets shows that our method has the highest dice coefficient of 73.06% and 65.40% on CTA and MRA datasets, respectively, outperforming the commonly used methods, such as U-Net and DeepMedic, which demonstrates the generalization potential of our network for segmenting different blood vessels. CONCLUSIONS: Our MDNet-Vb method demonstrates its superiority over other state-of-the-art methods, on both cardiac CTA and cerebral MRA datasets. For the network architecture, the MDNet-Vb combined the 3D U-Net and 3D FCN, which dramatically reduces the network parameters yet maintains the segmentation accuracy. The class-balanced loss at the voxel level further improves accuracy by properly alleviating the class-imbalanced issue between different classes. In summary, MDNet-Vb is promising for vessel segmentation from various volumetric medical images.


Assuntos
Processamento de Imagem Assistida por Computador , Tomografia Computadorizada por Raios X , Angiografia , Angiografia por Tomografia Computadorizada , Humanos
17.
Anal Bioanal Chem ; 413(17): 4493-4500, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34041573

RESUMO

Pepsinogen I (PGI) can reflect the morphology and function of the gastric mucosa. Accordingly, the large-scale community health screening of PGI can dramatically increase the early diagnosis rate of gastric cancer. However, PGI testing can only be carried out in comprehensive hospitals and health examination centers. To ameliorate this issue, a point-of-care chemiluminescent immunoassay for PGI was developed in a fully automated miniaturized instrument. This instrument was especially developed for health check-ups in the grassroots communities; its volume of which is only 0.18 m3. Critically, the entire detection process for a single sample only requires 20 min, and the samples can be loaded continuously, making the method suitable for high-throughput analysis. The assay displayed an excellent detection limit of 0.048 ng/mL with a broad detection range of 0-200 ng/mL. Furthermore, this assay exhibited high sensitivity and specificity, had low intra- and inter-assay coefficients of variation (<10%), and was not affected after storage at 37 °C for 7 days. The assay was used to detect PGI in 95 clinical serum samples, and the results were highly correlated with those that were clinically tested (correlation coefficient, R2 = 0.998). Hence, the method established in this work has great application value and can be broadly applied for the large-scale screening of gastric cancer in resource-limited areas.


Assuntos
Detecção Precoce de Câncer/instrumentação , Medições Luminescentes/instrumentação , Pepsinogênio A/sangue , Testes Imediatos , Neoplasias Gástricas/sangue , Humanos , Imunoensaio/instrumentação , Limite de Detecção , Neoplasias Gástricas/diagnóstico
18.
Hemoglobin ; 45(2): 133-135, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33843396

RESUMO

We report a novel mutation on the ß-globin gene, Hb Hezhou [ß64(E8)Gly→Ser; HBB: c.193G>A] that was detected in two unrelated Chinese individuals. Patient 1 also carried an α+-thalassemia (α+-thal) -α4.2 (leftward) deletion, but hematological analyses showed no clinical consequences. Patient 2 was heterozygous for Hb Hezhou. Hemoglobin (Hb) analysis was performed using capillary electrophoresis (CE) and high performance liquid chromatography (HPLC). The Hb variant remained undetected using HPLC, while an additional peak was detected by CE. The finding of Hb Hezhou indicates that the possibilities of rare Hb variants should be alerted in the thalassemia screening program and precisely diagnosed depending on the Hb separation technique used.

19.
Onco Targets Ther ; 14: 2789-2795, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33907421

RESUMO

Objective: Few studies have focused on investigating resistance mechanisms in myeloma immunotherapy. This study aimed to explore the relevant factor involved in the resistance of Elotuzumab and lenalidomide. Methods: Cell models which are resistant to Elotuzumab and lenalidomide were constructed; different expression genes in U266/WT (UW) and resistant UR, UE, and URE cells were detected by using gene expression microarray. RT-qPCR validated CCL20 mRNA expression of four cell lines and patient samples; bioinformatics analysis of CCL20 expressions in NDMM and RRMM; ELISA detected the presence of CCL20 in the plasma of MM patients; constructed UR mouse xenograft model to explore whether or not CCL20 reverse lenalidomide treatment in vivo. Results: Cell models which are resistant to Elotuzumab and lenalidomide (UR, UE, URE) were successfully constructed. CCL20 gene expression decreased in resistant myeloma cell lines and RRMM patients. Furthermore, RRMM patients were found to have lower levels of CCL20 protein in their plasma compared to NDMM. CCL20 increase the sensitivity of drug-resistant myeloma cells to immunomodulatory drugs both in vivo and in vitro. Conclusion: The expression of CCL20 was decreased in lenalidomide and Elotuzumab resistant U266 cells and in RRMM patients. CCL20 could therefore possibly increase the sensitivity of lenalidomide and Elotuzumab.

20.
Zhongguo Zhong Yao Za Zhi ; 46(1): 146-154, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33645064

RESUMO

This study aimed to assess whether chrysin(ChR) can inhibit epithelial-mesenchymal transition(EMT) of type Ⅱ alveolar epithelial cell and produce anti-pulmonary fibrosis effect by regulating the NF-κB/Twist 1 signaling pathway. Sixty rats were randomly divided into the control group, the bleomycin(BLC) group, BLC+ChR(50 mg·kg~(-1)) group and BLC+ChR(100 mg·kg~(-1)) group, with 15 rats in each group. The pulmonary fibrosis model was induced by intratracheal injection of BLC(7 500 U·kg~(-1)). Rats were orally administered with different doses of ChR after BLC injection for 28 days. The cells were divided into control group, TGF-ß1 group(5 ng·mL~(-1)), and TGF-ß1+ChR(1, 10, 100 µmol·L~(-1)) groups. The type Ⅱ alveolar epithelial cells were treated with TGF-ß1 for 24 h, and then treated with TGF-ß1 for 48 h in the presence or absence of different doses of ChR(1, 10 and 100 µmol·L~(-1)). The morphological changes and collagen deposition in lung tissues were analyzed by HE staining, Masson staining and immunohistochemistry. The mRNA and protein expression levels of collagen Ⅰ, E-cadherin, zonula occludens-1(ZO-1), vimentin, alpha smooth muscle actin(α-SMA), inhibitor of nuclear factor kappa B alpha(IκBα), nuclear factor-kappa B p65(NF-κB p65), phospho-NF-κB p65(p-p65) and Twist 1 in lung tissues and cells were detected by qPCR and Western blot, respectively. The animal experiment results showed that as compared with the BLC group, after administration of ChR for 28 days, bleomycin-induced pulmonary fibrosis in rats was significantly relieved, collagen Ⅰ expression in lung tissues was significantly reduced(P<0.05 or P<0.01), and EMT of alveolar epithelial cells was obviously inhibited [the expression levels of E-cadherin and ZO-1 were increased and the expression levels of vimentin and α-SMA were decreased(P<0.05 or P<0.01)], concomitantly with significantly reduced IκBα and p65 phosphorylation level in cytoplasm and decreased NF-κB p65 and Twist 1 expression in nucleus(P<0.05 or P<0.01). The cell experiment results showed that different doses of ChR(1, 10 and 100 µmol·L~(-1)) significantly reduced TGF-ß1-induced collagen Ⅰ expression(P<0.05 or P<0.01), significantly inhibited EMT of type Ⅱ alveolar epithelial cells[the expression levels of E-cadherin and ZO-1 were increased and the expression levels of vimentin and α-SMA were decreased(P<0.05 or P<0.01)], and inhibited IκBα and p65 phosphorylation in cytoplasm and down-regulated NF-κB p65 and Twist 1 expression in nucleus induced by TGF-ß1(P<0.05 or P<0.01). The results suggest that ChR can reverse EMT of type Ⅱ alveolar epithelial cell and alleviate pulmonary fibrosis in rats, and its mechanism may be associated with reducing IκBα phosphorylation and inhibiting NF-κB p65 phosphorylation and nuclear transfer, thus down-regulating Twist 1 expression.


Assuntos
Transição Epitelial-Mesenquimal , NF-kappa B , Células Epiteliais Alveolares/metabolismo , Animais , Flavonoides , NF-kappa B/genética , NF-kappa B/metabolismo , Ratos , Transdução de Sinais , Fator de Crescimento Transformador beta1/genética
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