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1.
Artigo em Inglês | MEDLINE | ID: mdl-35022968

RESUMO

Urban heat island (UHI) has a great influence on human wellbeing in urban areas. Previous studies have investigated impact on environment, ecosystem, and human health of UHI. To investigate economic impact of UHI is a lack of research. In this study, spatial-econometric hedonic housing price models are developed for estimating the marginal value of summer UHI in Beijing, China. The results showed that UHI effects in Beijing became severe from 2015 to 2017. The heat islands showed a mix of high and sub-high land surface temperature (LST). The spatial Durbin model estimates that one-unit increase of UHI intensity (UHII) would lower the housing value by 3.91%. Regarding the different districts, households had different attitudes to the UHI effect. Specifically, households regarded UHI effect as amenity in the four suburban districts with hills and relatively low LSTs; however, in most urban districts and their surroundings, households were willing to pay to avoid UHI effects with 13.0 dollars to 826.3 dollars for one-degree UHII decrease. This study highlights the urgent need for planners and decision-makers to consider urban expansion, UHI effect, and their economic impact in future urban planning.

2.
J Enzyme Inhib Med Chem ; 37(1): 178-188, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34894983

RESUMO

Diabetic nephropathy (DN) is one of the severe microvascular complications of diabetes mellitus. Oxidative stress resulting from aberrant metabolism of glucose mediates renal inflammation and fibrosis in the progression of DN. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor regulating the expression of antioxidant enzymes. Activating Nrf2 will give a promising therapy for DN. To discover novel Nrf2 activators, we have investigated caffeoylisocitric acid using mesangial cells under high glucose. The results showed at 10 µM, caffeoylisocitric acid significantly inhibited the self-limited proliferation of mesangial cells induced by high glucose. Further assessments have disclosed caffeoylisocitric acid mitigated oxidative stress, inflammation and accumulation of extracellular matrix resulting from high glucose via inactivating MAPK signalling. Meanwhile activation of Nrf2 was observed and involved in these effects through the interaction between Keap1 and caffeoylisocitric acid to disrupt Keap1-Nrf2 complex. Therefore, caffeoylisocitric acid is a promising Nrf2 activator targeting DN.

3.
Sci Total Environ ; 807(Pt 1): 150664, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34597546

RESUMO

The environmental impact, energy conservation, and economic cost are prominent decision criteria in municipal solid waste (MSW) management, among which trade-off relationships widely exist because of different features of pollutant treatment technologies. These three objectives should thereby be simultaneously considered in the design of technology combinations in MSW treatment system (MSWTS). In addition, comprehensive characterization of environmental impact of the whole MSWTS should cover the complex pollutants cross-media metabolism in the treatment of both MSW and subsequent secondary pollution. This study developed a multi-objective optimization model to select optimal technology solutions in MSWTS. Three objectives, the minimizations of total environmental impact calculated from pollutants cross-media metabolism perspective, net energy consumption, and total cost are optimized through the second generation of the Non-dominated Sorting Genetic Algorithm (NSGA-II). Final MSW management schemes under environment, energy, and cost preferences are obtained through Vlsekriterijumska Optimizacija I Kompromisno Resenje (VIKOR) method. This paper uses China's MSWTS as a case study and finds that Pareto optimal solutions can reduce the total environmental impact and the net energy consumption by 24.2% and 7.4% respectively, while increase the total cost by 18.2% in average, compared with the baseline scenario. The promotion of MSW biological treatment technologies, especially anaerobic digestion (AD), can effectively improve the environmental performance of MSWTS, while the current vigorous promotion of MSW incineration in China is not recommended. Sludge co-processing in cement kiln is highly promoted under all three types of management preferences. In summary, the proposed methodology can provide decision support for the optimal design of technology solutions in MSWTS.


Assuntos
Poluentes Ambientais , Eliminação de Resíduos , Gerenciamento de Resíduos , China , Conservação dos Recursos Naturais , Incineração , Resíduos Sólidos , Tecnologia
4.
Int Immunopharmacol ; 103: 108467, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34933161

RESUMO

Growing evidence indicates that synovial hypoxia-inducible factor 1α (HIF-1α) can be as a promising target for RA therapy. We previously reported that AMSP-30 m as a novel HIF-1α inhibitor had potent activities of anticancer metastasis. This study clarified the therapeutic effects of HIF-1α inhibitor AMSP-30 m on adjuvant-induced arthritis (AIA) in rats and explored the possible mechanisms. AMSP-30 m was given intraperitoneally to AIA rats, and its therapeutic effects and anti-inflammatory activity were evaluated. The influences of AMSP-30 m on synovial apoptosis, angiogenesis and sonic hedgehog (Shh) pathway were examined. We found that, accompanied with the inhibition of synovial HIF-1α expression, AMSP-30 m had potent anti-arthritic and anti-inflammatory effects on AIA rats, evidenced by the reduction in paw swelling, arthritis index, histopathological scores, and the production of IL-1ß, IL-6, TNF-α in serum and synovial tissues. AMSP-30 m reduced synovial Ki67 expression and increased TUNEL-positive index, indicating its anti-proliferative and pro-apoptotic effects on AIA synovial cells, which was related to reducing Bcl-2 protein level and increasing Bax, cleaved caspase 3 protein levels. Additionally, AMSP-30 m showed anti-angiogenic effects within AIA synovium, indicated by the reduction of synovial VEGF expression and blood vessels number (especially CD31+/αSMA- immature vessels, but not CD31+/αSMA+ mature vessels). Moreover, AMSP-30 m inhibited the activation of synovial Shh pathway, suggested by the reduction of pathway-related proteins, like Shh, Smo, Gli-1, cyclin D1 and c-Myc. Collectively, HIF-1α inhibitor AMSP-30 m exerted potent anti-arthritic effects on AIA rats possibly by promoting synovial apoptosis, reducing synovial angiogenesis and inhibiting Shh pathway.

5.
J Ethnopharmacol ; 283: 114670, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34653522

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Fritillariae thunbergii Miq (FTM)exhibit versatile biological activities including the significant antitussive and expectorant activities. As a herbal medicine, the therapeutic effects of FTM may be expressed by multi-components which have complicated integration effects on multi-targets. With the time going, the different processing methods of FTM has been changed a lot. Thus,the study described the effect of processing methods to FTM and its quality. MATERIAL AND METHOD: Studies were undertaken by using UHPLC-LTQ Orbitrap MS and pharmacodynamic models. All reagents were involved of analytical grade. While a HPLC-ELSD's method has been developed and validated, a certified Quality System is conformed to ICH requirements. The experimental animals followed the animal welfare guidelines. AIM OF THE STUDY: We aimed to found the differences after the different processing methods of FTM, and to demonstrate the changes could be selected as quality control indicators, and established a method for simultaneous determination of these for quality control. RESULTS: we have previously found two new steroidal alkaloids: zhebeininoside and imperialine-3-ß-D-glucoside from the different processing methods of FTM, which is the difference between the different processing methods of FTM, mainly on the steroidal alkaloids. The activity analysis of zhebeininoside, imperialine-3-ß-D-glucoside, verticine and verticinone showed that the mouse model of cough expectorant has antitussive effect. The positive drug selected was dextromethorphan syrup. The positive group showed biological activity, but the blank group showed nothing. The model group showed illness which means that the model was effective. There are two ways of the mechanism of action of the expectorant action which can make sputum thin, reduce its viscosity, and be easy to cough up, or can accelerate the movement of mucous cilia in the respiratory tract and promote the discharge of sputum. In our study, the content of phenol red was significantly reduced in the administration group. CONCLUSIONS: To sum up, our results suggest that zhebeininoside and other three components cloud be selected as quality control indicators, and a method for simultaneous determination of zhebeininoside and other three components was established for quality control.

6.
J Pharm Biomed Anal ; 207: 114396, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34670180

RESUMO

Euphorbia pekinensis Rupr. (EP) (Euphorbiaceae), as Traditional Chinese Medicine (TCM), exhibits therapeutic effects on tumors in clinical practice. Anti-angiogenesis may be an underlying molecular mechanism of EP's actions. However, the anti-angiogenic active ingredients of EP remain unclear. The screening and analysis of anti-angiogenic agents were essential for the sufficient utilization and development of EP. Thus, we established a UPLC-QTOF-MS method based on a transgenic zebrafish model to screen anti-angiogenesis activity components in EP. UPLC-QTOF-MS was used to characterize compounds from EP and in vivo compounds in Tg (flk1: mCherry) zebrafish larvae treated with EP. Based on the identification results, five components were selected, and their anti-angiogenesis activity were investigated via assessment of intersegmental blood vessels during the development of the transgenic zebrafish. Three of these components (3,3'-O-dimethoxy ellagic acid, quercetin, and ingenol) are active components of EP with anti-angiogenic effects. Among them, 3, 3'-O-dimethoxy ellagic acid and ingenol were first demonstrated with anti-angiogenesis effects. UPLC-PDA analysis was performed on EP water extracts to determine anti-angiogenesis active ingredients quantitatively. In the concentration range of 100-200 µg/mL, EP and the active ingredient compositions, mixed according to the content of EP, had equivalent anti-angiogenesis activities. These experimental results indicate that the UPLC-QTOF-MS method, combined with a transgenic zebrafish model, is rapid, sensitive and reliable. The combination in TCM offers the potential to achieve certain effect levels with lower concentrations of the individual compound.


Assuntos
Medicamentos de Ervas Chinesas , Euphorbia , Inibidores da Angiogênese/farmacologia , Animais , Animais Geneticamente Modificados , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/farmacologia , Medicina Tradicional Chinesa , Peixe-Zebra
7.
Dev Comp Immunol ; 127: 104309, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34748796

RESUMO

Insect C-type lectins (CTLs) play crucial roles in modulating the humoral and cellular immune responses. In the domesticated silkworm Bombyx mori L., BmCTL10 gene encodes an immulectin containing two carbohydrate recognition domains (CRDs). The phylogenetic analysis showed that BmCTL10 didn't cluster with other immulectin homologs in B. mori. BmCTL10 was mainly expressed in second to fifth instar larvae, wandering stage larvae, prepupa, and adults. In naïve fifth instar larvae, BmCTL10 was predominantly expressed in the fat body and epidermis. In second instar larvae, the topical application of Beauveria bassiana by immersion caused down-regulation of BmCTL10. The intra-hemocoel injection of E. coli, S. aureus, B. bassiana, and 20-hydroxyecdysone in fifth instar larvae caused tissue and time-specific inductions. The recombinant protein (rBmCTL10) can bind to larval hemocytes and various pathogen-associated molecular patterns to enhance hemocyte-mediated nodulation, phagocytosis, and encapsulation. rBmCTL10 caused significant upregulation of most antimicrobial peptides and nitric oxide synthase 1 in hemocytes in vivo. Yeast two-hybrid demonstrated that integrin ß3 and ß4 subunits can interact with BmCTL10. Furthermore, only CRD2 can interact with the ß3, while both CRD1 and CRD2 can interact with the ß4. Taken together, this study showed that BmCTL10 has multiple functions in the innate immune responses of B. mori and two integrin ß subunits are their potential receptors.

8.
J Environ Manage ; 304: 114217, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34883435

RESUMO

COVID-19 has spread worldwide, leading to a significant impact on daily life. Numerous studies have confirmed that people have changed their travel to urban green spaces during the COVID-19 pandemic. However, in China, where COVID-19 has been effectively controlled, how the travel behavior of visitors to urban parks has changed under different risk levels (RLs) of COVID-19 is unclear. Faced with these gaps, we took a highly developed city, Wuhan, as a case study and a questionnaire survey was conducted with 3276 respondents to analyze the changes in park visitors' travel behaviors under different COVID-19 RLs. Using a stated preference (SP) survey method, four RLs were assigned: new cases in other provinces (RL1), Hubei province (RL2), Wuhan (RL3), and in the district of the park (RL4). The results indicated that visitors reduced their willingness to visit urban parks, with 78.39%, 37.97%, and 13.34% of visitors remaining under RL2, RL3, and RL4, respectively. Furthermore, the service radius of urban parks also shrank from 4230 m under no new cases of COVID-19 to approximately 3000 m under RL3. A higher impact was found for visitors using public transport, those with a higher income and higher education, and female visitors. Based on the modified travel behaviors, the Gaussian-based two-step floating catchment area (2SFCA) method was used to evaluate the accessibility and the Gini coefficient was calculated to represent the equality of the urban parks. A higher RL led to lower accessibility and greater inequitable access. The results should help the government guide residents' travel behaviors after COVID-19.

9.
Front Pharmacol ; 12: 724525, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34858170

RESUMO

Asthma is one of the most common chronic pulmonary disorders, affecting more than 330 million people worldwide. Unfortunately, there are still no specific treatments for asthma so far. Therefore, it is very important to develop effective therapeutics and medicines to deal with this intractable disease. Berberine (Ber) has fabulous anti-inflammatory and antibacterial effects, while its low water solubility and bioavailability greatly limit its curative efficiency. To improve the nasal mucosa absorption of poorly water-soluble drugs, such as Ber, we developed a platelet membrane- (PM-) coated nanoparticle (NP) system (PM@Ber-NPs) for targeted delivery of berberine to the inflammatory lungs. In vivo, PM@Ber-NPs exhibited enhanced targeting retention in the inflammatory lungs compared with free Ber. In a mouse model of house dust mite- (HDM-) induced asthma, PM@Ber-NPs markedly inhibited lung inflammation, as evident by reduced inflammatory cells and inflammatory cytokines in the lung compared with free Ber. Collectively, our study demonstrated the inhibitory actions of nasally delivered nanomedicines on HDM-induced asthma, primarily through regulating Th1/Th2 balance by enhancing IL-12 expression which could potentially reduce lung inflammation and allergic asthma.

10.
Elife ; 102021 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-34964713

RESUMO

Recently, aCPSF1 was reported to function as the long-sought global transcription termination factor of archaea; however, the working mechanism remains elusive. This work, through analyzing transcript-3'end-sequencing data of Methanococcus maripaludis, found genome-wide positive correlations of both the terminator uridine(U)-tract and aCPSF1 with hierarchical transcription termination efficacies (TTEs). In vitro assays determined that aCPSF1 specifically binds to the terminator U-tract with U-tract number-related binding affinity, and in vivo assays demonstrated the two elements are indispensable in dictating high TTEs, revealing that aCPSF1 and the terminator U-tract cooperatively determine high TTEs. The N-terminal KH domains equip aCPSF1 with specific-binding capacity to terminator U-tract and the aCPSF1-terminator U-tract cooperation; while the nuclease activity of aCPSF1 was also required for TTEs. aCPSF1 also guarantees the terminations of transcripts with weak intrinsic terminator signals. aCPSF1 orthologs from Lokiarchaeota and Thaumarchaeota exhibited similar U-tract cooperation in dictating TTEs. Therefore, aCPSF1 and the intrinsic U-rich terminator could work in a noteworthy two-in-one termination mode in archaea, which may be widely employed by archaeal phyla; using one trans-action factor to recognize U-rich terminator signal and cleave transcript 3'-end, the archaeal aCPSF1-dependent transcription termination may represent a simplified archetypal mode of the eukaryotic RNA polymerase II termination machinery.

11.
J Healthc Eng ; 2021: 3433615, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34900182

RESUMO

Effective drug intervention is the most important method to improve the prognosis, improve the quality of life, and prolong the life of patients with heart failure. This study aimed to explore the protective effect of astragaloside IV on myocardial cell injury induced by oxidized low-density lipoprotein (OxLDL) and its regulatory mechanism on the increase of brain natriuretic peptide (BNP) caused by myocardial cell injury. The model of myocardial cell injury, protection, and histone deacetylase (HDAC) inhibition in HL-1 mice was established by OxLDL treatment, astragaloside IV intervention, and UF010 coincubation. The effects of OxLDL and astragaloside IV on apoptosis were detected by flow cytometry. The expression level of BNP mRNA and protein in cells was investigated by real-time fluorescence quantification, western blot, and enzyme-linked immunosorbent assay. HDAC activity in nucleus was calibrated by fluorescence absorption intensity. Enzyme-linked immunosorbent assay (ELISA) was applied to test eNOS level in myocardial cells. OxLDL significantly promoted apoptosis, upregulated BNP mRNA, increased BNP protein level inside and outside cells, and decreased eNOS level. Compared with OxLDL treatment group, apoptosis decreased, BNP mRNA expression level decreased, BNP protein concentration decreased, and eNOS level increased significantly combined with low and high concentration astragaloside IV treatment group. HDAC activity significantly increased in OxLDL treatment group and significantly decreased after combined incubation with low and high concentrations of astragaloside IV. Inhibition of HDAC significantly increased eNOS level and decreased BNP protein level. In conclusion, astragaloside IV can reverse the low level of eNOS caused by OxLDL by regulating HDAC activity to protect myocardial cells from oxide damage, which is manifested by the decrease of BNP concentration.


Assuntos
Histona Desacetilases , Peptídeo Natriurético Encefálico , Animais , Lipoproteínas LDL , Camundongos , Qualidade de Vida , Saponinas , Triterpenos
12.
Eur J Ophthalmol ; : 11206721211069457, 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34939452

RESUMO

OBJECTIVE: This study evaluates the epidemiological characteristics, ophthalmological manifestations, and different therapeutic options available for patients with multiple sclerosis (MS) in China, Spain, and Cuba. METHODS: A self-designed questionnaire was used to conduct a comparable descriptive cross-sectional study on patients with MS. The survey included patients' demographic data, ocular manifestations related to MS, and treatment methodology followed in the three countries. The online survey was designed using the Wenjuanxing survey platform, and a survey link was circulated through WhatsApp, WeChat, and emails. Quantitative data were expressed as mean and standard deviation, the Kruskal-Wallis test was used for non-parametric variables. Qualitative data were expressed as numerical and percentage. The chi-square test (χ2) was used to compare the group's response categories. The statistical difference was considered significant when p < 0.05. RESULTS: The female-to-male ratio in all the three countries was 2-3:1, and relapsing-remitting MS (RRMS) was the most frequent in all three countries. Vision loss was slow and progressive in half of the patients from the three countries, with no significant differences (p = 0.524). A higher percentage of steroid treatment was observed in Chinese patients in comparison with the patients from other two countries (p < 0.001), and a similar trend was seen in the use of traditional medicines. Almost one-third of patients who did not receive any treatment recovered spontaneously in all the three countries (p = 0.097). CONCLUSIONS: MS occurs more frequently in the relapsing-remitting clinical form and there is a clear female predominance. The first ocular crisis or clinical debut of MS is characterized by slow and progressive visual impairment, increasing and adding to other ocular manifestations during its evolutionary course. Spontaneous recovery of vision after an attack of optic neuritis in the course of MS is possible.

13.
Environ Microbiol ; 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34951085

RESUMO

Anaerobic oxidation of methane (AOM) is a microbial process degrading ample methane in anoxic environments, and Ca. Methanoperedens mediated nitrate- or metal-reduction linked AOM is believed important in freshwater systems. This work, via 16S rRNA gene diversity survey and 16S rRNA quantification, found abundant Ca. Methanoperedens along with iron in the cold Zoige wetland at Tibetan Plateau. The wetland soil microcosm performed Fe(III) reduction, rather than nitrate- nor sulphate-reduction, coupled methane oxidation (3.87 µmol d-1 ) with 32.33 µmol Fe(II) accumulation per day at 18°C, but not at 30°C. A metagenome-assembled genome (MAG) recovered from the microcosm exhibits ~74% average nucleotide identity with the reported Ca. Methanoperedens spp. that perform Fe(III) reduction linked AOM, thus a novel species Ca. Methanoperedens psychrophilus was proposed. Ca. M. psychrophilus contains the whole suite of CO2 reductive methanogenic genes presumably involving in AOM via a reverse direction, and comparative genome analysis revealed its unique gene categories: the multi-heme clusters (MHCs) cytochromes, the S-layer proteins highly homologous to those recovered from lower temperature environments and type IV pili, those could confer Ca. M. psychrophilus of cold adaptability. Therefore, this work reports the first methanotroph implementing AOM in an alpine wetland.

14.
Micromachines (Basel) ; 12(12)2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34945425

RESUMO

SiC direct bonding using O2 plasma activation is investigated in this work. SiC substrate and n- SiC epitaxy growth layer are activated with an optimized duration of 60s and power of the oxygen ion beam source at 20 W. After O2 plasma activation, both the SiC substrate and n- SiC epitaxy growth layer present a sufficient hydrophilic surface for bonding. The two 4-inch wafers are prebonded at room temperature followed by an annealing process in an atmospheric N2 ambient for 3 h at 300 °C. The scanning results obtained by C-mode scanning acoustic microscopy (C-SAM) shows a high bonding uniformity. The bonding strength of 1473 mJ/m2 is achieved. The bonding mechanisms are investigated through interface analysis by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX). Oxygen is found between the two interfaces, which indicates Si-O and C-O are formed at the bonding interface. However, a C-rich area is also detected at the bonding interface, which reveals the formation of C-C bonds in the activated SiC surface layer. These results show the potential of low cost and efficient surface activation method for SiC direct bonding for ultrahigh-voltage devices applications.

15.
J Healthc Eng ; 2021: 3843830, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956570

RESUMO

This study aimed to investigate the protective effect and molecular mechanism of spironolactone in isoproterenol-induced cardiomyocyte hypertrophy. In this study, primary cardiomyocytes were extracted from the heart of neonatal rats. After stable culture, they were processed with isoproterenol alone or isoproterenol (10 µM) combined with different doses (low dose of 10 µM and high dose of 50 µM), and the cellular activity was determined by MTT experiment. The volume of cells was measured with an inverted microscope and CIAS-1000 cell image analysis system. The mRNA expression levels of ANP and BNP in cells were explored by RT-qPCR. The levels of ANP and BNP proteins and NFATc3 phosphorylation in the nucleus were detected by western blot. The extracellular Ca2+ concentration and CaN activity were measured by colorimetry with the kit. Isoproterenol significantly enlarged the volume of cardiomyocytes (p < 0.001), upregulated mRNA and expression levels of ANP and BNP proteins (p < 0.001), increased extracellular Ca2+ concentration and CaN activity (p < 0.001), and upregulated NFATc3 phosphorylation in the nucleus (p < 0.001). The volume of cells treated with isoproterenol combined with different doses of spironolactone significantly decreased compared with those treated with isoproterenol alone (p < 0.001). mRNA and expression levels of ANP and BNP proteins downregulated significantly (p < 0.001). The extracellular Ca2+ (p < 0.01) concentration and CaN activity (p < 0.001) decreased significantly, and NFATc3 phosphorylation in the nucleus downregulated significantly (p < 0.001). There was no significant difference in cell volume (p=0.999), ANP and BNP mRNA (p=0.695), expression levels of proteins, CaN activity (0.154), and NFATc3 phosphorylation in the nucleus between the cells treated with isoproterenol combined with high-dose spironolactone and those in the control group. In conclusion, spironolactone can reverse isoproterenol-induced cardiomyocyte hypertrophy by inhibiting the Ca2+/CaN/NFATc3 pathway.


Assuntos
Calcineurina , Cálcio/metabolismo , Miócitos Cardíacos , Fatores de Transcrição NFATC/metabolismo , Espironolactona , Animais , Calcineurina/metabolismo , Hipertrofia , Ratos , Espironolactona/farmacologia
16.
J Biomed Semantics ; 12(1): 22, 2021 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-34922629

RESUMO

BACKGROUND: Image segmentation is a difficult and classic problem. It has a wide range of applications, one of which is skin lesion segmentation. Numerous researchers have made great efforts to tackle the problem, yet there is still no universal method in various application domains. RESULTS: We propose a novel approach that combines a deep convolutional neural network with a grabcut-like user interaction to tackle the interactive skin lesion segmentation problem. Slightly deviating from grabcut user interaction, our method uses boxes and clicks. In addition, contrary to existing interactive segmentation algorithms that combine the initial segmentation task with the following refinement task, we explicitly separate these tasks by designing individual sub-networks. One network is SBox-Net, and the other is Click-Net. SBox-Net is a full-fledged segmentation network that is built upon a pre-trained, state-of-the-art segmentation model, while Click-Net is a simple yet powerful network that combines feature maps extracted from SBox-Net and user clicks to residually refine the mistakes made by SBox-Net. Extensive experiments on two public datasets, PH2 and ISIC, confirm the effectiveness of our approach. CONCLUSIONS: We present an interactive two-stage pipeline method for skin lesion segmentation, which was demonstrated to be effective in comprehensive experiments.


Assuntos
Redes Neurais de Computação
17.
Cells ; 10(11)2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-34831036

RESUMO

Autophagy is an evolutionarily conserved pathway, in which cytoplasmic components are sequestered within double-membrane vesicles called autophagosomes and then transported into lysosomes or vacuoles for degradation. Over 40 conserved autophagy-related (ATG) genes define the core machinery for the five processes of autophagy: initiation, nucleation, elongation, closure, and fusion. In this review, we focus on one of the least well-characterized events in autophagy, namely the closure of the isolation membrane/phagophore to form the sealed autophagosome. This process is tightly regulated by ESCRT machinery, ATG proteins, Rab GTPase and Rab-related proteins, SNAREs, sphingomyelin, and calcium. We summarize recent progress in the regulation of autophagosome closure and discuss the key questions remaining to be addressed.

19.
Comput Math Methods Med ; 2021: 7145487, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34765014

RESUMO

Background: Traditional mass spectrometry detection methods have low detection efficiency for low-abundance proteins, thus limiting the application of proteomic analysis in the diagnosis of preeclampsia. Magnetic nanomaterials have good superparamagnetism and have obvious advantages in the field of biological separation and enrichment. Aim: The objective of this study is to explore the value of superparamagnetic iron oxide nanoparticles in the proteomic analysis of preeclampsia. Materials and Methods: 42 patients and 40 normal pregnant women were selected in this study for analysis. Gene Ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were performed to evaluate the function of these differential proteins. Proteomic analysis was used to analyze the differential proteins. Color Doppler ultrasound technology was used to detect changes in the blood flow of the fetal umbilical artery and cerebral artery. Results: 16 differential proteins in the serum of pregnant women with preeclampsia and normal pregnant women were detected. The 16 proteins are mainly related to angiogenesis and endothelial function proteins, coagulation cascade proteins, placental growth factor, and so on. Biological function analysis revealed that these proteins are mainly enriched in the nuclear factor kB (NF-κB) signaling pathway. Moreover, our data suggested that compared with the fetus in the uterus of normal pregnant women, the umbilical artery S/D, PI, and RI of the fetus in preeclampsia were greatly increased, and the cerebral artery S/D, PI, and RI were greatly decreased. Conclusion: Biological function analysis revealed that 16 proteins are mainly enriched in the NF-κB signaling pathway. Compared with the normal group, the umbilical artery S/D, PI, and RI of the preeclampsia group were greatly increased, and the cerebral artery S/D, PI, and RI were all greatly reduced. Our findings provided a more comprehensive reference for us to study the mechanism of preeclampsia at the molecular level and also provide data support for the screening of relevant markers for early diagnosis of preeclampsia.

20.
Signal Transduct Target Ther ; 6(1): 375, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34728602

RESUMO

The scope and variety of the metabolic intermediates from the mitochondrial tricarboxylic acid (TCA) cycle that are engaged in epigenetic regulation of the chromatin function in the nucleus raise an outstanding question about how timely and precise supply/consumption of these metabolites is achieved in the nucleus. We report here the identification of a nonclassical TCA cycle in the nucleus (nTCA cycle). We found that all the TCA cycle-associated enzymes including citrate synthase (CS), aconitase 2 (ACO2), isocitrate dehydrogenase 3 (IDH3), oxoglutarate dehydrogenase (OGDH), succinyl-CoA synthetase (SCS), fumarate hydratase (FH), and malate dehydrogenase 2 (MDH2), except for succinate dehydrogenase (SDH), a component of electron transport chain for generating ATP, exist in the nucleus. We showed that these nuclear enzymes catalyze an incomplete TCA cycle similar to that found in cyanobacteria. We propose that the nTCA cycle is implemented mainly to generate/consume metabolic intermediates, not for energy production. We demonstrated that the nTCA cycle is intrinsically linked to chromatin dynamics and transcription regulation. Together, our study uncovers the existence of a nonclassical TCA cycle in the nucleus that links the metabolic pathway to epigenetic regulation.

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