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1.
Urol Oncol ; 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34620554

RESUMO

PURPOSE: To establish a nomogram for the prediction of postoperative cancer-specific survival (CSS) in patients with nonmetastatic T3a renal cell carcinoma (RCC). METHODS: The Surveillance, Epidemiology, and End Results database were searched for patients with pT3aN0-1M0 RCC between 2010 and 2018. The patients were randomly stratified into the training and verification group (7:3 ratio). Using Cox regression analysis, the predictors for the CSS in the training group were integrated to establish the nomogram for predicting the 3-year and 5-year CSS. Harrell's concordance index (C-index), time-dependent receiver operating characteristic curve, decision curve analysis, and Kaplan-Meier survival analysis were used to evaluate the nomogram performance. RESULTS: A total of 5,791 pT3aN0-1M0 RCC cases with eligible data were selected from the Surveillance, Epidemiology, and End Results database. Age, tumor size, surgery type, Fuhrman grade, histological type, sarcomatoid, N stage, and invasion patterns were identified as the significant predictors for CSS to establish the nomogram. The C-indices of the nomogram were 0.774 (95% CI: 0.753-0.795) and 0.777 (95% CI: 0.745-0.809) for the training and verification group, respectively. The calibration of the nomogram revealed consistency between the predicted and observed survival. The area under the 3-year and 5-year CSS receiver operating characteristic curves were 0.773 and 0.786 in the training group, respectively. Decision curve analysis showed the optimal application of the model in clinical decision-making. According to the cutoff values of prognostic indices, patients with low-risk showed better CSS than those with high-risk in both training and verification groups (both P< 0.0001). CONCLUSION: The current nomogram could effectively predict the CSS of patients with nonmetastatic T3a RCC, and could be used to identify patients who might need a compact interval of follow-up and postoperative adjuvant systemic treatment. The limitations included the retrospective nature, absence of external validation, and several unmeasured variables related to the selection bias of surgery type. The results should be interpreted with caution.

2.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(5): 573-579, 2021 Sep 30.
Artigo em Chinês | MEDLINE | ID: mdl-34628776

RESUMO

OBJECTIVE: To explore the feasibility of using the bidirectional local distance based medical similarity index (MSI) to evaluate automatic segmentation on medical images. METHODS: Taking the intermediate risk clinical target volume for nasopharyngeal carcinoma manually segmented by an experience radiation oncologist as region of interest, using Atlas-based and deep-learning-based methods to obtain automatic segmentation respectively, and calculated multiple MSI and Dice similarity coefficient (DSC) between manual segmentation and automatic segmentation. Then the difference between MSI and DSC was comparatively analyzed. RESULTS: DSC values for Atlas-based and deep-learning-based automatic segmentation were 0.73 and 0.84 respectively. MSI values for them varied between 0.29~0.78 and 0.44~0.91 under different inside-outside-level. CONCLUSIONS: It is feasible to use MSI to evaluate the results of automatic segmentation. By setting the penalty coefficient, it can reflect phenomena such as under-delineation and over-delineation, and improve the sensitivity of medical image contour similarity evaluation.


Assuntos
Planejamento da Radioterapia Assistida por Computador , Estudos de Viabilidade
3.
Math Biosci Eng ; 18(5): 6672-6699, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34517551

RESUMO

We study the existence of global unique classical solution to a density-dependent prey-predator population system with indirect prey-taxis effect. With two Lyapunov functions appropriately constructed, we then show that the solution can asymptotically approach prey-only state or coexistence state of the system under suitable conditions. Moreover, linearized analysis on the system at these two constant steady states shows their linear instability criterion. By numerical simulation we find that some density-dependent prey-taxis and predators' diffusion may either flatten the spatial one-dimensional patterns which exist in non-density-dependent case, or break the spatial two-dimensional distribution similarity which occurs in non-density-dependent case between predators and chemoattractants (released by prey).


Assuntos
Modelos Biológicos , Comportamento Predatório , Animais , Simulação por Computador , Difusão , Ecossistema , Dinâmica Populacional
4.
Anal Chem ; 93(39): 13152-13160, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34551257

RESUMO

Single-cell EV (extracellular vesicle) secretion analysis is emerging for a better understanding of non-genetic cellular heterogeneity regulating human health and diseases through intercellular mediators. However, the requirements of expensive and bulky instrumentations hinder its widespread use. Herein, by combining gold nanoparticle-enhanced silver staining and the Poisson distribution, we reported the use of a home-use scanner to realize high-throughput single-cell EV secretion analysis without cell counting. We applied the platform to analyze the secretions of different EV phenotypes with the human oral squamous cell carcinoma cell line and primary cells from patients, which generated single-cell results comparable with those of the immunofluorescence approach. Notably, we also realized the quantification of the number of EVs secreted from every single cell using their respective titration curves obtained from population samples, making it possible to directly compare different EV phonotypes in regard to their secretion number, secretion rate, and so forth. The technology introduced here is simple, easy to operate, and of low cost, which make it a potential, easily accessible, and affordable tool for widespread use in both basic and clinical research.


Assuntos
Carcinoma de Células Escamosas , Vesículas Extracelulares , Nanopartículas Metálicas , Neoplasias Bucais , Ouro , Humanos
5.
Ann Palliat Med ; 10(8): 9184-9191, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34488404

RESUMO

BACKGROUND: This study aimed to investigate the distribution pattern of carbapenemases and evaluate their solitary contribution to carbapenem resistance. METHODS: One hundred and twelve isolates of Acinetobacter baumannii (A. baumannii) isolated from the intensive care unit (ICU) of a southern China tertiary hospital were identified, and antimicrobial susceptibility tests (ASTs) of these strains were determined. Common carbapenemases were detected and the distribution pattern of carbapenemases was analyzed. Logistic regression and general linear model analyzed were performed to identify the correlation between antimicrobial susceptibility and carbapenemase genes. RESULTS: These 112 strains were classified into a carbapenem-resistant A. baumannii (CRAB) group (71.7%) and a carbapenem-susceptible A. baumannii (CSAB) group (28.3%). Carbapenemase genes, including blaOXA-51-like (100.0%), blaOXA-23 (93.4%), ISAba1/blaOXA-51-like (27.5%), blaNDM-1 (8.8%), blaOXA-24 (2.2%) and blaOXA-58 (2.2%) were detected in CRAB strains, and no blaSIM, blaVIM and blaIMP gene in these 112 isolates. There was a statistically significant difference between CSAB and CRAB group in carrying blaOXA-23 (P<0.001) and ISAba1/blaOXA-51-like (P=0.024). CONCLUSIONS: A pattern of blaOXA-51-like (100.0%), blaOXA-23 (93.4%), blaNDM-1 (8.8%), blaOXA-24 (2.2%) and blaOXA-58 (2.2%) was detected in CRAB strains. BlaOXA-23-like and ISAba1/blaOXA-51-like complex might be more relevant to carbapenem resistance in A. baumannii. Harboring blaOXA-23-like and ISAba1/blaOXA-51-like complex might increase the possibility of resistance 2.16 times [risk ratio (RR): 2.16; 95% confidence interval (CI): 1.04-4.51] and 1.29 times (RR: 1.29; 95% CI: 1.07-1.56), respectively.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter baumannii/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias , Humanos , Testes de Sensibilidade Microbiana , beta-Lactamases
6.
IEEE Trans Cybern ; PP2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34495865

RESUMO

In this study, a graph regularized algorithm for early expression detection (EED), called GraphEED, is proposed. EED is aimed at detecting the specified expression in the early stage of a video. Existing EED detectors fail to explicitly exploit the local geometrical structure of the data distribution, which may affect the prediction performance significantly. According to manifold learning, the data in real-world applications are likely to reside on a low-dimensional submanifold embedded in the high-dimensional ambient space. The proposed graph Laplacian consists of two parts: 1) a k-nearest neighbor graph is first constructed to encode the geometrical information under the manifold assumption and 2) the entire expressions are regarded as the must-link constraints since they all contain the complete duration information and it is shown that this can also be formulated as a graph regularization. GraphEED is to have a detection function representing these graph structures. Even with the inclusion of the graph Laplacian, the proposed GraphEED has the same computational complexity as that of the max-margin EED, which is a well-known learning-based EED, but the detection performance has been largely improved. To further make the model appropriate in large-scale applications, with the technique of online learning, the proposed GraphEED is extended to the so-called online GraphEED (OGraphEED). In OGraphEED, the buffering technique is employed to make the optimization practical by reducing the computation and storage cost. Extensive experiments on three video-based datasets have demonstrated the superiority of the proposed methods in terms of both effectiveness and efficiency.

7.
J Magn Reson Imaging ; 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34545977

RESUMO

BACKGROUND: Partial bile duct ligation (PBDL) model is a reliable cholestatic fibrosis experimental model that showed complex histopathological changes. Magnetic resonance imaging (MRI) features of PBDL have not been well characterized. PURPOSE: To investigate the potential of MRI parameters in assessing fibrosis in PBDL and explore the relationships between MRI and pathological features. ANIMAL MODEL: Established PBDL models. POPULATION: Fifty-four mice were randomly divided into four timepoints PBDL groups and one sham group. FIELD STRENGTH/SEQUENCE: 3.0 T; MRI sequences included T1-weighted fast spin-echo (FSE), T2-weighted single shot FSE, variable flip angle T1 mapping, multi-echo SE T2 mapping, multi-echo gradient-echo T2* mapping, and multi-b-value diffusion-weighted imaging. ASSESSMENT: MRI examination was performed at the corresponding timepoints after surgery. Native T1, ΔT1 (T1native-T1post), T2, T2*, apparent diffusion coefficient (ADC) values, histogram parameters (skewness and kurtosis), intravoxel incoherent motion parameters (f, D, and D* ) within the entire ligated (PBDL), non-ligated liver (PBDL), and whole liver (sham) were obtained. Fibrosis and inflammation were assessed in Masson and H&E staining slices using the Metavir and activity scoring system. STATISTICAL TESTS: One-way ANOVA, Spearman's rank correlation, and receiver operating characteristic curves were performed. P < 0.05 was considered statistically significant. RESULTS: Fibrosis and inflammation were finally staged as F3 and A3 in ligated livers but were not observed in non-ligated or sham livers. Ligated livers displayed significantly elevated native T1, ΔT1, T2, and reduced ADC and T2* than other livers. Spearman's correlation showed better correlation with inflammation (r = 0.809) than fibrosis (r = 0.635) in T2 and both ΔT1 and ADC showed stronger correlation with fibrosis (r = 0.704 and r = -0.718) than inflammation (r = 0.564 and r = -0.550). Area under the curve (AUC) for ΔT1 performed the highest (0.896). When combined with all relative parameters, AUC increased to 0.956. DATA CONCLUSION: Multiparametric MRI can evaluate and differentiate pathological changes in PBDL. ΔT1 and ADC better correlated with fibrosis while T2 stronger with inflammation. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 2.

8.
Sci Rep ; 11(1): 18029, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34504267

RESUMO

Southern corn rust is a destructive maize disease caused by Puccinia polysora Underw that can lead to severe yield losses. However, genomic information and microsatellite markers are currently unavailable for this disease. In this study, we generated a total of 27,295,216 high-quality cDNA sequence reads using Illumina sequencing technology. These reads were assembled into 17,496 unigenes with an average length of 1015 bp. The functional annotation indicated that 8113 (46.37%), 1933 (11.04%) and 5516 (31.52%) unigenes showed significant similarity to known proteins in the NCBI Nr, Nt and Swiss-Prot databases, respectively. In addition, 2921 (16.70%) unigenes were assigned to KEGG database categories; 4218 (24.11%), to KOG database categories; and 6,603 (37.74%), to GO database categories. Furthermore, we identified 8,798 potential SSRs among 6653 unigenes. A total of 9 polymorphic SSR markers were developed to evaluate the genetic diversity and population structure of 96 isolates collected from Guangdong Province in China. Clonal reproduction of P. polysora in Guangdong was dominant. The YJ (Yangjiang) population had the highest genotypic diversity and the greatest number of the multilocus genotypes, followed by the HY (Heyuan), HZ (Huizhou) and XY (Xinyi) populations. These results provide valuable information for the molecular genetic analysis of P. polysora and related species.

10.
Neuro Endocrinol Lett ; 42(5): 312-320, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34506095

RESUMO

OBJECTIVE: To investigate the negative feedback regulation from rat hippocampus on hypothalamic-pituitary-adrenal (HPA) axis under high temperature and high humidity stress. METHODS: Thirty (30) SD male rats were randomly divided into three groups: control group, high temperature and high humidity group, drug intervention group. The rats in control group were kept in the environment with temperature of 24 ± 1°C and humidity of 50 ± 5%, without any stimulation. The rats in the other groups were exposed to high temperature and high humidity environment for 4 h each day, with temperature of 35±1 °C and humidity of 85±5%. The rats in drug intervention group were intragastrically administered with the glucocorticoid receptor antagonist mifepristone. The administration was continued for 3 weeks. After 3 weeks, the serum levels of corticotropin releasing hormone (CRH), adrenocorticotropic hormone (ACTH) and corticosterone (CORT) were detected by ELISA.The protein and mRNA levels of corticosteroid receptors (MR), glucocorticoid receptors (GR) and inducible nitric oxide synthase (iNOS), transient receptor potential vanilloid 1 (TRPV1) and 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1) in hippocampus were determined by immunohistochemistry and in situ hybridization, respectively. The apoptosis of hippocampal cells was examined with TUNEL apoptosis staining. RESULTS: After stimulation with high temperature and high humidity stress for 3 weeks, the serum levels of CRH, ACTH and CORT in the high temperature and high humidity group were significantly increased compared to that of control group; the levels of these indicators in drug intervention group were decreased compared to that of high temperature and high humidity group (P<0.05). In high temperature and high humidity group, the protein and mRNA levels of MR, GR, iNOS in hippocampus of rats were significantly increased compared with that of control group (p<0.05); and the levels of these indicators in drug intervention group were lower than that of high temperature and high humidity group (p<0.05). In addition, compared with the control group, the TRPV1 protein level in hippocampus of rats in high temperature and high humidity group was not significantly changed (p>0.05), while the TRPV1 mRNA level was significantly increased (p<0.05). Neither the protein nor mRNA levels of 11ß-HSD1 showed significant difference compared to control group (p>0.05). The apoptosis of hippocampus cells in the high temperature and high humidity group was significantly increased compared with that of control group (p<0.05); and it was lower in the drug intervention group than that of in high temperature and high humidity group while the result was not significant (p>0.05). CONCLUSION: High temperature and high humidity stress may up-regulate the local expression of iNOS in hippocampus and decrease the activity of glucocorticoids (GC) receptor, then the effective binding of GR-GC would be decreased and the negative feedback regulation of hippocampus on HPA axis would be inhibited. The glucocorticoid receptor antagonist can improve the negative feedback regulation of hippocampus on HPA axis in rat.

11.
Nanoscale ; 13(33): 14008-14015, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34477681

RESUMO

Lieb lattice, a two-dimensional edge-centered square lattice, has attracted considerable interest due to its exotic electronic and topological properties. Although various optical and photonic Lieb lattices have been experimentally demonstrated, it remains challenging for an electronic Lieb lattice to be realized in real material systems. Here, based on first-principles calculations and tight-binding modeling, a silver sulfide (Ag2S) monolayer is reported as a long-sought-after inorganic electronic Lieb lattice. This Lieb-lattice Ag2S is further found to be ultrasoft, which enables its electronic properties and topological states near the Fermi level to be finely tuned, as evidenced by the strain-induced topologically non-trivial edge states near the valence band edge. These results not only provide an ideal platform to further explore and harvest interesting quantum properties but also pave a way to pursue other inorganic electronic Lieb lattices in a broader material domain.

12.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4145-4149, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34467726

RESUMO

With repeated silica gel, octadecyl silica(ODS), and Sephadex LH-20 column chromatography, normal-phase and reverse-phase high performance liquid chromatography(HPLC), etc., a pair of new enantiomers and 5 known compounds were separated from the 95% ethanol extract of Chloranthus multistachys. These compounds were identified by the nuclear magnetic resonance spectroscopy(including 1 D-NMR and 2 D-NMR), single-crystal X-ray diffraction, circular dichroism(CD) spectroscopy, mass spectrometry(MS), and some other methods as(1R,4R,5R,8S,10R)-chloraeudolide H(1 a),(1S,4S,5S,8R,10S)-chloraeudolide H(1 b), hydroxyisogermafurenolide(2), 4α-hydroxy-5α,8ß(H)-eudesm-7(11)-en-8,12-olide(3), chloraniolide A(4), chlorantene D(5), 4α,8ß-dihydroxy-5α(H)-eudesm-7(11)-en-8,12-olide(6). Compounds 1 a and 1 b are a pair of new eudesmane-type sesquiterpene enantiomers, and compounds 2-4 were isolated from C. multistachys for the first time.


Assuntos
Sesquiterpenos , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Estereoisomerismo
13.
Zhongguo Zhong Yao Za Zhi ; 46(15): 3789-3796, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34472251

RESUMO

The genus Chloranthus has 13 species and 5 varieties in China, which can be found in the southwest and northeast regions. Phytochemical studies on Chloranthus plants have reported a large amount of terpenoids, such as diterpenoids, sesquiterpenoids, and sesquiterpenoid dimers. Their anti-inflammation, anti-tumor, antifungal, antivirus, and neuroprotection activities have been confirmed by previous pharmacological research. Herein, research on the chemical constituents from Chloranthus plants and their biological activities over the five years was summarized to provide scientific basis for the further development and utilization of Chloranthus plants.


Assuntos
Diterpenos , Sesquiterpenos , Compostos Fitoquímicos/farmacologia , Plantas , Sesquiterpenos/farmacologia , Terpenos
14.
BMC Infect Dis ; 21(1): 841, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34416851

RESUMO

AIM: This study has conducted a comparative analysis of common carbapenemases harboring, the expression of resistance-nodulation-cell division (RND) family efflux pumps, and biofilm formation potential associated with carbapenem resistance among Acinetobacter baumannii (A. baumannii) strains with different carbapenem susceptibility. METHODS: A total of 90 isolates of A. baumannii from two tertiary hospitals of China were identified and grouped as carbapenem susceptible A. baumannii (CSAB) strains and carbapenem non-susceptible A. baumannii (CnSAB) strains based on the susceptibility to imipenem. Harboring of carbapenemase genes, relative expression of RND family efflux pumps and biofilm formation potential were compared between the two groups. RESULT: Among these strains, 12 (13.3 %) strains were divided into the CSAB group, and 78 (86.7 %) strains into the CnSAB group. Compared with CSAB strains, CnSAB strains increased distribution of blaOXA-23 (p < 0.001) and ISAba1/blaOXA-51-like (p = 0.034) carbapenemase genes, and a 6.1-fold relative expression of adeB (p = 0.002), while CSAB strains led to biofilm formation by 1.3-fold than CnSAB strains (p = 0.021). CONCLUSIONS: Clinically, harboring more blaOXA-23-like and ISAba1/blaOXA-51-like complex genes and overproduction of adeABC are relevant with carbapenem resistance, while carbapenem susceptible strains might survive the stress of antibiotic through their ability of higher biofilm formation.


Assuntos
Acinetobacter baumannii , Acinetobacter baumannii/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Biofilmes , Carbapenêmicos/farmacologia , Divisão Celular , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
15.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 37(3): 225-229, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34374231

RESUMO

Objective: To investigate the relationship between mitochondrial DNA (mtDNA) variation and high altitude essential hypertension(HAEH) in the Chinese Tajik population. Methods: Fifty-three patients with HAEH and 46 healthy subjects were enrolled from the Chinese Tajik population. The mtDNA fragments were amplificated by polymerase chain reaction, and products were sequenced to acquire full sequence of mtDNA. The mtDNA sequences of all subjects were compared to the Cambridge sequence to explore mtDNA variations and analyze difference between HAEH and healthy controls. Online softwares were applied to predict function changes caused by positive associated mtDNA variations. Results: Compared to the control group, the frequency of haplogroup U4b was significant higher in HAEH group(P=0.023,OR=7.062,CI(95%)=1.306-38.182), and the frequencies of 8 mutations from haplogroup U4b showed a significant difference between the HAEH group and control group (all with P values below 0.05). The mt DNA15693T>C mutation was the only missense mutation, which affected amino acid 316 in mitochondrial cytochrome b (MTCYB) by changing it from methionine to threonine. Bioinformatics analysis indicated that the mutation in MTCYB may play a biological role through affecting the second structure of protein. Conclusion: MtDNA subhaplogroup U4b is a genetic factor for HAEH in the Chinese Tajik population, and mtDNA15693T>C mutation may be an important molecular mechanism of HAEH.


Assuntos
DNA Mitocondrial , Predisposição Genética para Doença , Altitude , Grupo com Ancestrais do Continente Asiático/genética , China , DNA Mitocondrial/genética , Hipertensão Essencial/genética , Haplótipos , Humanos , Mutação
16.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 37(4): 343-348, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34374251

RESUMO

Objective: To analyze the long non-coding RNA (lncRNA) and messenger RNA (mRNA) co-expression network changes induced by mtDNA3010A/G mutation in acute hypoxia, and to investigate the role of key lncRNA and mRNA in the regulation of gene expression induced by hypoxia. Methods: The genotype combinations A-C-C and G-C-C of mitochondrial DNA 3010-5178-10400 were screened, and genotypes of mtDNA3010A and mtDNA3010G fusion cells were constructed by using osteosarcoma cell treated by ethidium bromide without mitochondrion (ρ0206 cell) as donors. After treatment with 1% O2 24 h, the lncRNA - mRNA expression chip was applied to detect the differently expressed lncRNA and mRNA in two kinds of fusing cells, and fluorescence quantitative polymerase chain method was used to verify differently expressed mRNA. Bioinformatics methods were applied to build co-expression network of lncRNA-mRNA, predict target genes of differently expressed lncRNA, and the functions of differently expressed mRNA and target genes predicted by lncRNA were also analyzed based on gene ontology (GO) and the Kyoto encyclopedia of genes and genomes (KEGG) forecast analysis. Results: After treatment with 1% O2 for 24 h, compared with mtDNA3010G fusion cells: 688 lncRNAs were up-regulated, 21 were more than 2 times; 1098 were down-regulated, and 4 were more than 2 times. There were 1151 mRNA expressions up-regulated, 14 were more than 2 times, 539 mRNA expressions were down-regulated, and 3 were more than 2 times. Conclusion: MtDNA3010A/G genotype mutation under hypoxia is able to affect the lncRNA-mRNA regulatory network, and the differentially expressed lncRNA and mRNA may play an important role in regulation network of gene expression induced by hypoxia, which is expected to be a target for the regulation of hypoxia reaction from the perspective of mitochondria.


Assuntos
RNA Longo não Codificante , Perfilação da Expressão Gênica , Genótipo , Humanos , Hipóxia/genética , Mutação , RNA Longo não Codificante/genética , RNA Mensageiro/genética
17.
J Colloid Interface Sci ; 606(Pt 1): 223-235, 2021 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-34390990

RESUMO

Recently, two-dimensional MXene demonstrated promising advantages to improve the flame-retardant performance of composites; however, its compatibility with polymer matrix is a great concern. In this study, MXene was first functionalized with phosphorylated chitosan (PCS) to obtain the PCS-MXene nanohybrid. The resulting nanohybrid was introduced into the thermoplastic polyurethane (TPU) matrix via solution mixing followed by the hot-pressing method, affording TPU/PCS-MXene nanocomposite. The resulting nanohybrid exhibited superior compatibility with the TPU matrix, enhancing mechanical performance of the TPU/PCS-MXene nanocomposite compared to the pristine TPU and TPU/MXene nanocomposite. Besides, the flame-retardant performance of TPU/PCS-MXene nanocomposite was greatly enhanced, while the smoke emission was effectively suppressed. As only 3 wt% PCS-MXene was introduced, peak heat release rate, total heat release, and total smoke production of the composite decreased by 66.7%, 21.0%, and 27.7%, respectively, compared to the pristine TPU. Systematical characterization was then carried out to investigate the enhancement mechanism of PCS-MXene, highlighting the crucial role of PCS combined with the catalytic effect of MXene. In brief, the compatibility issues of MXene were effectively addressed, and its flame-retardancy enhanced greatly via the PCS modification, the bio-based characteristic of which, in turn greatly benefits the further development of MXene-polymer composite.

18.
Curr Med Imaging ; 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34455965

RESUMO

BACKGROUND: Manual segment target volumes were time-consuming and inter-observer variability couldn't be avoided. With the development of computer science, auto-segmentation had the potential to solve this problem. OBJECTIVE: To evaluate the accuracy and stability of Atlas-based and deep-learning-based auto-segmentation of the intermediate risk clinical target volume, composed of CTV2 and CTVnd, for nasopharyngeal carcinoma quantitatively. METHODS AND MATERIALS: A cascade-deep-residual neural network was constructed to automatically segment CTV2 and CTVnd by deep learning method. Meanwhile, a commercially available software was used to automatically segment the same regions by Atlas-based method. The datasets included contrast computed tomography scans from 102 patients. For each patient, the two regions were manually delineated by one experienced physician. The similarity between the two auto-segmentation methods was quantitatively evaluated by Dice similarity coefficient, the 95th Hausdorff distance, volume overlap error and relative volume difference, respectively. Statistical analyses were performed using the ranked Wilcoxon test. RESULTS: The average Dice similarity coefficient (±standard deviation) given by the deep-learning-based and Atlas-based auto-segmentation were 0.84(±0.03) and 0.74(±0.04) for CTV2, 0.79(±0.02) and 0.68(±0.03) for CTVnd, respectively. For the 95th Hausdorff distance, the corresponding values were 6.30±3.55mm and 9.34±3.39mm for CTV2, 7.09±2.27mm and 14.33±3.98mm for CTVnd. Besides, volume overlap error and relative volume difference could also predict the same situations. Statistical analyses showed significant difference between the two auto-segmentation methods (p<0.01). CONCLUSIONS: Compared with the Atlas-based segmentation approach, the deep-learning-based segmentation method performed better both in accuracy and stability for meaningful anatomical areas other than organs at risk.

19.
Dis Markers ; 2021: 6649579, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34413914

RESUMO

Background: To evaluate whether the overexpression of chemokine receptor-7 (CXCR7) in prostatic tissues obtained from men with Castration-Resistant Prostate Cancer (CRPC) is associated with resistance to enzalutamide (Enza). Methods: Based on the inclusion criteria of CRPC in EAU guidelines, all eligible patients treated in our hospital from January 2015 to December 2019 were included. Cases underwent radical prostatectomy, docetaxel-based chemotherapy, or new endocrine therapies (including Enza or abiraterone), and cases with severe cardiopulmonary disease or other malignant tumors were excluded. After immunohistochemical staining for CXCR7 expression in prostatic biopsy tissues, all enrolled cases were divided into two groups, namely, the CXCR7-positive group and the CXCR7-negative group. And then, PSA response to Enza treatment was recorded in detail and comparatively analyzed. In addition, the Cox proportional hazard modeling and the Kaplan-Meier analysis were used to determine PSA progression-free survival (PSAP-FS) and clinical or radiographic progression-free survival (CRP-FS) in this cohort. Results: A total of 79 CRPC individuals were enrolled and evaluated in this study. Median follow-up durations were 24 months (range, 12-42) in the CXCR7-positive group (n = 47) and 28.5 months (range, 12-42) in the CXCR7-negative group (n = 32). The patients with lower CXCR7 expression showed much better PSA response to Enza treatment. There was 84.4% of CXCR7- cases showing decreasing PSA response, while there were 71.4% in the CXCR7/1+ group and 31.2% in the CXCR7/2+ group, respectively. All patients in the CXCR7/3+ group showed increasing PSA response to Enza treatment. And the percentage of patients whose PSA decreased over 50% is significantly higher in the CXCR7-negative group than in the CXCR7-positive group (68.8% vs. 8.5%, P < 0.001), and the percentage of patients whose PSA decreased over 90% is also remarkably higher in the CXCR7-negative group (43.8% vs. 0, P < 0.001). The Kaplan-Meier analysis demonstrated that the oncologic outcomes of CXCR7-negative patients were improved much significantly by Enza treatment in comparison with those of CXCR7-positive patients. Significantly increased median PSAP-FS (21 months vs. 6 months, P < 0.0001) and CRP-FS (27 months vs. 9 months, P < 0.0001) were obtained in the CXCR7-negative group. The further stratified analysis in all CXCR7-positive patients demonstrated that the patients with higher CXCR7 expression showed much worse outcome. The median time of PSAP-FS was 21 months in the CXCR7/1+ group, 9 months in the CXCR7/2+ group, and 6 months in the CXCR7/3+ group, while the median time of CRP-FS was 21 months in the CXCR7/1+ group, 12 months in the CXCR7/2+ group, and 6 months in the CXCR7/3+ group, respectively. Conclusion: Overexpression of CXCR7 induced by an AR antagonist in CRPC patients displays much better treatment response to Enza. CXCR7 might be a novel therapeutic target gene for CRPC patients.

20.
Artigo em Inglês | MEDLINE | ID: mdl-34460403

RESUMO

Recurrent neural networks (RNNs) continue to show outstanding performance in sequence learning tasks such as language modeling, but it remains difficult to train RNNs for long sequences. The main challenges lie in the complex dependencies, gradient vanishing or exploding, and low resource requirement in model deployment. In order to address these challenges, we propose dynamic recurrent routing neural networks (DRRNets), which can: 1) shorten the recurrent lengths by allocating recurrent routes dynamically for different dependencies and 2) reduce the number of parameters significantly by imposing low-rank constraints on the fully connected layers. A novel optimization algorithm via low-rank constraint and sparsity projection is developed to train the network. We verify the effectiveness of the proposed method by comparing it with multiple competitive approaches in several popular sequential learning tasks, such as language modeling and speaker recognition. The results in terms of different criteria demonstrate the superiority of our proposed method.

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