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1.
Food Chem ; 367: 130653, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34343809

RESUMO

A uniform spherical structure covalent organic framework (TAPA-BPDA-COF) was prepared by a facile method at room temperature with tris(4-aminophenyl)amine (TAPA) and 4,4'-biphenyldicarboxaldehyde (BPDA) as building blocks. Based on the solid phase extraction with the TAPA-BPDA-COF as the sorbent and high performance liquid chromatography-diode array detection, a sensitive analytical method was established for the determination of four neonicotinoid insecticides from water and honey samples. Under the optimum conditions, good linear response for the quantification of the analytes was achieved in the range of 0.3-50.0 ng mL-1 for water samples and in the range of 8.0-500.0 ng g-1 for honey samples. The method recoveries fell in the range of 80.0-121.9% with RSDs less than 7.6%. The limits of detection at the signal to noise ratio of 3 were measured to be in the range of 0.08-0.12 ng mL-1 for water samples and 2.6-3.3 ng g-1 for honey samples, depending on compounds.


Assuntos
Inseticidas , Estruturas Metalorgânicas , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Neonicotinoides , Extração em Fase Sólida
2.
Phytother Res ; 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34494324

RESUMO

Although paclitaxel is a promising frontline chemotherapy agent for various malignancies, the clinical applications have been restricted by side effects, drug resistance, and cancer metastasis. The combination of paclitaxel and other agents could be the promising strategies against malignant tumor, which enhances the antitumor effect through synergistic effects, reduces required drug concentrations, and also suppresses tumorigenesis in multiple ways. In this study, we found that luteolin, a natural flavonoid compound, combined with low-dose paclitaxel synergistically regulated the proliferation, migration, epithelial-mesenchymal transition (EMT), and apoptosis of esophageal cancer cells in vitro, as well as synergistically inhibited tumor growth without obvious toxicity in vivo. The molecular mechanism of inhibiting cell migration and EMT processes may be related to the inhibition of SIRT1, and the mechanism of apoptosis induction is associated with the reactive oxygen species (ROS)/c-Jun N-terminal kinase (JNK) pathway-mediated activation of mitochondrial apoptotic pathway.

3.
Endocrinology ; 162(12)2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34453520

RESUMO

The human testis can be infected by a large number of RNA and DNA viruses. While various RNA virus infections may induce orchitis and impair testicular functions, DNA virus infection rarely affects the testis. Mechanisms underlying the differential effects of RNA and DNA viral infections on the testis remain unclear. In the current study, we therefore examined the effects of viral RNA and DNA sensor signaling pathways on mouse Sertoli cells (SC) and Leydig cells (LC). The local injection of viral RNA analogue polyinosinic-polycytidylic acid [poly(I:C)] into the testis markedly disrupted spermatogenesis, whereas the injection of the herpes simplex virus (HSV) DNA analogue HSV60 did not affect spermatogenesis. Poly(I:C) dramatically induced the expression of the proinflammatory cytokines tumor necrosis factor α (TNF-α) and interleukin 6 in SC and LC through Toll-like receptor 3 and interferon ß promoter stimulator 1 signaling pathways, impairing the integrity of the blood-testis barrier and testosterone synthesis. Poly(I:C)-induced TNF-α production thus plays a critical role in the impairment of cell functions. In contrast, HSV60 predominantly induced the expression of type 1 interferons and antiviral proteins via the DNA sensor signaling pathway, which did not affect testicular cell functions. Accordingly, the Zika virus induced high levels of TNF-α in SC and LC and impaired their respective cellular functions, whereas Herpes simplex virus type 2 principally induced antiviral responses and did not impair such functions. These results provide insights into the mechanisms by which RNA viral infections impair testicular functions.

4.
Theor Appl Genet ; 134(11): 3759-3772, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34355268

RESUMO

KEY MESSAGE: An enhanced grain weight locus from Agropyron cristatum chromosome 7P was verified in two wheat backgrounds, localized to the 7PS1-2 region. Novel translocation lines with this locus were evaluated. Agropyron cristatum is a wild relative of wheat that harbours elite genes for wheat improvement. The wheat-A. cristatum 7P disomic addition line II-5-1 exhibits high grain weight. Here, to dissect the genetic basis of grain weight contributed by A. cristatum chromosome 7P in wheat backgrounds, four segregated populations of the addition line were developed and evaluated in two wheat backgrounds. The results showed that A. cristatum chromosome 7P can stably and significantly increase the grain weight by approximately 2 g, mainly by increasing grain length at different grain weight levels of the wheat background. The locus for increased grain weight from chromosome 7P shows dominant inheritance independent of the wheat background. Moreover, two deletion lines and 23 translocation lines were identified by cytological methods and molecular markers, and an enlarged chromosome 7P bin map was constructed with 158 STS markers and 40 bin intervals. With the genetic populations of these deletion and translocation lines, the genetic locus of increased grain weight was narrowed down to bin 7PS1-2. Two translocation lines (7PT-A18 and 7PT-B4) with smaller 7P chromosomal segments exhibited an increase in grain weight, grain length and grain width simultaneously. These translocation lines carrying the 7PS1-2 chromosomal fragment will be valuable genetic resources for wheat grain weight improvement. Collectively, this study uncovers the grain weight locus from chromosome 7P and provides novel pre-breeding lines with enhanced grain weight.

5.
J Int Med Res ; 49(7): 3000605211023696, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34256638

RESUMO

Esophageal tuberculosis is rare among digestive system diseases. We herein present two cases of esophageal tuberculosis. One patient presented with a choking sensation and pain in the chest, and the other presented with loss of appetite and emaciation. Both patients had an esophagomediastinal fistula, underwent endoscopic ultrasonography and fine-needle aspiration, were clinically diagnosed with esophageal tuberculosis, received antituberculosis treatment, and exhibited clinical improvement. These two rare cases suggest that the possibility of esophageal tuberculosis should be considered in patients with an esophagomediastinal fistula. Endoscopic ultrasonography and fine-needle aspiration can be performed to assist the diagnosis. Good clinical results can often be achieved with timely antituberculosis treatment.


Assuntos
Fístula , Tuberculose , Antituberculosos/uso terapêutico , Endossonografia , Esôfago/diagnóstico por imagem , Humanos , Tuberculose/complicações , Tuberculose/diagnóstico por imagem , Tuberculose/tratamento farmacológico
6.
Sensors (Basel) ; 21(13)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206783

RESUMO

Hyperspectral technology is used to obtain spectral and spatial information of samples simultaneously and demonstrates significant potential for use in seed purity identification. However, it has certain limitations, such as high acquisition cost and massive redundant information. This study integrates the advantages of the sparse feature of the least absolute shrinkage and selection operator (LASSO) algorithm and the classification feature of the logistic regression model (LRM). We propose a hyperspectral rice seed purity identification method based on the LASSO logistic regression model (LLRM). The feasibility of using LLRM for the selection of feature wavelength bands and seed purity identification are discussed using four types of rice seeds as research objects. The results of 13 different adulteration cases revealed that the value of the regularisation parameter was different in each case. The recognition accuracy of LLRM and average recognition accuracy were 91.67-100% and 98.47%, respectively. Furthermore, the recognition accuracy of full-band LRM was 71.60-100%. However, the average recognition accuracy was merely 89.63%. These results indicate that LLRM can select the feature wavelength bands stably and improve the recognition accuracy of rice seeds, demonstrating the feasibility of developing a hyperspectral technology with LLRM for seed purity identification.


Assuntos
Oryza , Algoritmos , Modelos Logísticos , Sementes , Tecnologia
7.
J Int Med Res ; 49(7): 3000605211032786, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34308693

RESUMO

OBJECTIVE: To compare the clinical efficacy and safety of dexmedetomidine and propofol in patients who underwent gastrointestinal endoscopy. METHODS: Relevant studies comparing dexmedetomidine and propofol among patients who underwent gastrointestinal endoscopy were retrieved from databases such as PubMed, Embase, and Cochrane Library. RESULTS: Seven relevant studies (dexmedetomidine group, n = 238; propofol group, n = 239) met the inclusion criteria. There were no significant differences in the induction time (weighted mean difference [WMD] = 3.46, 95% confidence interval [CI] = -0.95-7.88, I2 = 99%) and recovery time (WMD = 2.74, 95% CI = -2.72-8.19, I2 = 98%). Subgroup analysis revealed no significant differences in the risks of hypotension (risk ratio [RR] = 0.56, 95% CI = 0.25-1.22) and nausea and vomiting (RR = 1.00, 95% CI = 0.46-2.22) between the drugs, whereas dexmedetomidine carried a lower risk of hypoxia (RR = 0.26, 95% CI = 0.11-0.63) and higher risk of bradycardia (RR = 3.01, 95% CI = 1.38-6.54). CONCLUSIONS: Dexmedetomidine had similar efficacy and safety profiles as propofol in patients undergoing gastrointestinal endoscopy.


Assuntos
Dexmedetomidina , Hipotensão , Propofol , Dexmedetomidina/efeitos adversos , Endoscopia Gastrointestinal , Humanos , Hipnóticos e Sedativos/efeitos adversos , Propofol/efeitos adversos , Resultado do Tratamento
8.
Plant Dis ; 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34129353

RESUMO

Powdery mildew and leaf rust, caused by Blumeria graminis f. sp. tritici (Bgt) and Puccinia triticina (Pt), respectively, are widespread diseases of wheat worldwide. Utilizing resistant cultivars is considered as the most economical, environmental-friendly, and effective method to control these diseases. In the present study, a collection of 2,978 wheat accessions consisting of 1,394 advanced breeding lines, 1,078 Chinese cultivars, 291 introduced cultivars, 132 lines containing alien chromosomes, and 83 landraces was tested for reactions to powdery mildew and leaf rust. The results indicated that 659 (22.1%) wheat accessions were highly resistant to a widely prevalent Bgt isolate, E09, at the seedling stage, and 390 were consistently resistant to the mixture of Bgt isolates at the adult-plant stage. Meanwhile, 63 (2.1%) accessions were highly resistant to leaf rust at the adult-plant stage, of which 54 were resistant to a predominant and highly virulent Pt race, THTT, at the seedling stage. Notably, 17 accessions were resistant to both powdery mildew and leaf rust. To detect known genes for resistance to powdery mildew and leaf rust, these accessions were tested with gene-specific or tightly linked markers for seven Pm genes (Pm2, Pm4, Pm5, Pm6, Pm8, Pm21, and Pm24) and ten Lr genes (Lr1, Lr9, Lr10, Lr19, Lr20, Lr24, Lr26, Lr34, Lr37, and Lr46). Of the 659 powdery mildew-resistant accessions, 328 might carry single Pm genes and 191 carry combined Pm genes. Pm2 was detected at the highest frequency of 59.6%, followed by Pm8, Pm6, Pm21, Pm4, and Pm5, while Pm24 was not detected. Besides, 139 accessions might contain unknown Pm genes different from those tested in this study. In the 63 accessions resistant leaf rust, four Lr genes (Lr1, Lr10, Lr26, and Lr34) were detected in 41 accessions either singly or in combination, while six genes (Lr9, Lr19, Lr20, Lr24, Lr37, and Lr46) were not detected. Twenty-two accessions might contain unknown Lr genes different from those tested in this study. This study not only provided important information for rationally distributing resistance genes in wheat breeding programs, but also identified resistant germplasm that might have novel genes to enrich the diversity of resistance sources.

9.
J Chromatogr A ; 1651: 462301, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34107399

RESUMO

In this work, a core-shell structured magnetic covalent organic framework named as M-TpDAB was constructed with 3,3'-diaminobenzidine (DAB) and 1,3,5-triformylphloroglucinol (Tp) as building units. M-TpDAB was characterized by infrared spectroscopy, nitrogen adsorption-desorption isotherms, powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Using the M-TpDAB as adsorbent, a simple and highly effective method was proposed for preconcentrating phenylurea herbicides before high performance liquid-phase chromatography analysis. In the optimized conditions, a good linearity was achieved within the range of 0.15-100 ng mL-1 for water sample, 1.0-100.0 ng mL-1 for tea drink samples. The limits of detection for the analytes were 0.05-0.15 ng mL-1 for water sample and 0.30-0.50 ng mL-1 for drink samples. Satisfactory recoveries of spiked target compounds were in the range of 84.6%-105% for water sample and 80.3%-102% for tea drink samples. Finally, the M-TpDAB based method was successfully used to determine phenylurea herbicides in tea drinks and water samples, demonstrating a good alternative for analyzing trace level of phenylurea herbicides in water samples.


Assuntos
Herbicidas/isolamento & purificação , Estruturas Metalorgânicas/química , Compostos de Fenilureia/isolamento & purificação , Extração em Fase Sólida/métodos , Água/química , Adsorção , Cromatografia Líquida de Alta Pressão , Água Potável/química , Herbicidas/análise , Fenômenos Magnéticos , Magnetismo/métodos , Compostos de Fenilureia/análise , Difração de Raios X
10.
BMC Neurol ; 21(1): 190, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33975554

RESUMO

BACKGROUND: The aim of this study was to evaluate the effect of surgical resection and stereotactic biopsy on the complication rate, progression-free survival (PFS) and overall survival (OS) of 70 patients diagnosed at a single institution with primary central nervous system lymphoma (PCNSL) and to explore the predictors of selection for resection and the prognostic factors of PCNSL. METHODS: A retrospective analysis was performed of 70 patients with PCNSL that was diagnosed by surgical resection or stereotactic brain biopsy in our department from January 2013 to May 2019. We divided the patients into two groups: a resection group (n = 28) and a stereotactic biopsy group (n = 42). Data on clinical characteristics, imaging findings, complication rates, PFS and OS were retrospectively reviewed and compared between these two groups. We also analysed the predictors of selection for resection and prognostic factors of PCNSL by multivariate analysis. RESULTS: The median age was 53.3 ± 14.3 years, and there was a male predominance with a sex ratio of 1.33:1. The most common clinical manifestation was a headache. The complication rate in the resection group was 10.7% versus 7.1% in the stereotactic biopsy group, and there was no statistically significant difference. The rate of improvement in symptoms of the resection group was significantly higher than that of the stereotactic biopsy group. Multivariable analysis identified a single tumour and not involving deep structures as predictors of selection for resection. With a median follow-up of 30 months (range 1-110), the mean OS and PFS of all patients were 16.1 months and 6.2 months, respectively. Patients who underwent surgical resection had a mean OS of 23.4 months and PFS of 8.6 months versus 11.2 months and 4.6 months for those who had a brain biopsy performed. In addition, multivariable analysis showed that not involving deep structures and resection were favourable prognostic factors for PCNSL. CONCLUSIONS: The outcomes of patients with PCNSL treated in our cohort are still poor. In our series, surgical resection might play a role in significantly improving OS and PFS compared with stereotactic biopsy in a subset of patients. The type of surgery and tumour location are prognostic factors for PCNSL.


Assuntos
Neoplasias do Sistema Nervoso Central/cirurgia , Linfoma não Hodgkin/cirurgia , Adulto , Idoso , Neoplasias do Sistema Nervoso Central/mortalidade , Estudos de Coortes , Feminino , Humanos , Biópsia Guiada por Imagem/métodos , Linfoma não Hodgkin/mortalidade , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/métodos , Prognóstico , Estudos Retrospectivos , Técnicas Estereotáxicas
11.
Biol Reprod ; 105(1): 113-127, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-33899078

RESUMO

Three major pathogenic states of the prostate, including benign prostatic hyperplasia, prostate cancer, and prostatitis, are related to the local inflammation. However, the mechanisms underlying the initiation of prostate inflammation remain largely unknown. Given that the innate immune responses of the tissue-specific cells to microbial infection or autoantigens contribute to local inflammation, this study focused on pattern recognition receptor (PRR)-initiated innate immune responses in mouse prostatic epithelial cells (PECs). Primary mouse PECs abundantly expressed Toll-like receptor 3 (TLR3), TLR4, TLR5, melanoma differentiation-associated protein 5 (MDA5), and IFN-inducible protein 16 (p204 in mouse). These PRRs can be activated by their respective ligands: lipopolysaccharide (LPS) and flagellin of Gram-negative bacteria for TLR4 and TLR5, polyinosinic-polycytidylic acid (poly(I:C)) for TLR3 and MDA5, and herpes simplex virus DNA analog (HSV60) for p204. LPS and flagellin predominantly induced the expression of inflammatory cytokines, including tumor necrosis factor alpha (TNFA), interleukin 6 (IL6), chemokines monocyte chemoattractant protein-1 (MCP1), and C-X-C motif chemokine 10 (CXCL10). Poly(I:C) and HSV60 predominantly induced the expression of type 1 interferons (IFNA and IFNB) and antiviral proteins: Mx GTPase 1, 2',5'-oligoadenylate synthetase 1, and IFN-stimulated gene 15. The replication of mumps virus in PECs was inhibited by type 1 IFN signaling. These findings provide insights into the mechanisms underlying innate immune response in the prostate.

12.
Front Immunol ; 12: 580454, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679733

RESUMO

Numerous types of viruses have been found in human semen, which raises concerns about the sexual transmission of these viruses. The overall effect of semen on viral infection and transmission have yet to be fully investigated. In the present study, we aimed at the effect of seminal plasma (SP) on viral infection by focusing on the mumps viral (MuV) infection of HeLa cells. MuV efficiently infected HeLa cells in vitro. MuV infection was strongly inhibited by the pre-treatment of viruses with SP. SP inhibited MuV infection through the impairment of the virus's attachment to cells. The antiviral activity of SP was resistant to the treatment of SP with boiling water, Proteinase K, RNase A, and DNase I, suggesting that the antiviral factor would not be proteins and nucleic acids. PNGase or PLA2 treatments did not abrogate the antiviral effect of SP against MuV. Further, we showed that the prostatic fluid (PF) showed similar inhibition as SP, whereas the epididymal fluid and seminal vesicle extract did not inhibit MuV infection. Both SP and PF also inhibited MuV infection of other cell types, including another human cervical carcinoma cell line C33a, mouse primary epididymal epithelial cells, and Sertoli cell line 15P1. Moreover, this inhibitory effect was not specific to MuV, as the herpes simplex virus 1, dengue virus 2, and adenovirus 5 infections were also inhibited by SP and PF. Our findings suggest that SP contains a prostate-derived pan-antiviral factor that may limit the sexual transmission of various viruses.


Assuntos
Antivirais/imunologia , Células Epiteliais/imunologia , Vírus da Caxumba/imunologia , Sêmen/imunologia , Vírus/imunologia , Animais , Antivirais/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Chlorocebus aethiops , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Células HeLa , Interações Hospedeiro-Patógeno/imunologia , Humanos , Masculino , Camundongos Endogâmicos C57BL , Vírus da Caxumba/fisiologia , Sêmen/metabolismo , Sêmen/virologia , Células Vero
13.
J Int Med Res ; 49(1): 300060520985363, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33472479

RESUMO

OBJECTIVES: Chlorogenic acid (CGA) is an antioxidant dietary factor. We investigated the effects of CGA on endothelial cell dysfunction in diabetic mice and the mechanistic role of nuclear factor erythroid-related factor 2 (Nrf2) in the antioxidant effect of CGA. METHODS: Diabetic (db/db) mice were fed normal chow or chow containing 0.02% CGA for 12 weeks. Human umbilical vein endothelial cells (HUVECs) and mouse aortas were treated with normal or high glucose. RESULTS: CGA treatment induced upregulation of Nrf2 in HUVECs in a dose-dependent manner. CGA pretreatment prevented reactive oxygen species generation and preserved nitric oxide bioavailability in HUVECs and aortas from wild-type but not Nrf2-/- mice. CGA improved endothelium-dependent relaxation in high glucose-treated aortas from wild-type and db/db mice, but not Nrf2-/- mice. Dietary CGA improved endothelium-dependent relaxation in db/db mice. CONCLUSIONS: CGA ameliorates endothelial dysfunction in diabetic mice through activation of the Nrf2 anti-oxidative pathway.


Assuntos
Diabetes Mellitus Experimental , Fator 2 Relacionado a NF-E2 , Animais , Ácido Clorogênico/metabolismo , Ácido Clorogênico/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Endotélio Vascular , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo
14.
Int Immunopharmacol ; 92: 107339, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33516048

RESUMO

BACKGROUND: Inflammation and oxidative stress is closely associated with the development of ischemic brain stroke. Opa-interacting protein 5 antisense RNA 1 (OIP5-AS1), a novel identified long non-coding RNA (lncRNA), has been suggested to play an important role in the development of many types of human cancers. However, the functional involvement of OIP5-AS1 in ischemic stroke is still unknown. METHODS: Quantitative real-time polymerase chain reaction and /or western blot were conducted to determine the expression profiles of OIP5-AS1, C1q/TNF-related protein 3 (CTRP3) and miR-186-5p in the serum of stroke patients, as well as in the ischemic penumbra of rats with middle cerebral artery occlusion/reperfusion (MCAO/R) injury and microglial cells treated with oxygen glucose deprivation/re-oxygenation (OGD/R). Upon selective regulation of OIP5-AS1 and miR-186-5p, the inflammation and oxidative stress responses in microglia/macrophage as well as neurologic functions in MCAO/R rats were detected. Furthermore, the interactions between OIP5-AS1 and miR-186-5p, miR-186-5p and CTRP3 were investigated by RNA immunoprecipitation (RIP) assay, luciferase report assay and bioinformation anaylsis. RESULTS: We observed markedly increased infarct volume, neuronal apoptosis, inflammation and oxidative stress responses in the infarcted lesions of MCAO/R rats, in line with down-regulated levels of OIP5-AS1 and CTRP3 while up-regulated miR-186-5p. Functional studies demonstrated that up-regulation of OIP5-AS1 attenuated infarct volume, neuronal apoptosis, microglia/macrophage inflammation and oxidative stress responses induced by MCAO/R or OGD/R. In terms of mechanism, we revealed that OIP5-AS1-miR-186-5p-CTRP3 axis played a vital role in modulating microglia/macrophage activation and neuronal apoptosis. CONCLUSION: Up-regulating lncRNA OIP5-AS1 protects neuron injury against MCAO/R induced inflammation and oxidative stress in microglia/macrophage through activating CTRP3 via sponging miR-186-5p.


Assuntos
Hipóxia-Isquemia Encefálica/complicações , Inflamação/prevenção & controle , MicroRNAs/genética , Neurônios/metabolismo , Estresse Oxidativo , RNA Longo não Codificante/genética , Fatores de Necrose Tumoral/metabolismo , Animais , Células Cultivadas , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Humanos , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Microglia/metabolismo , Microglia/patologia , Neurônios/patologia , Ratos , Transdução de Sinais , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/prevenção & controle
15.
IEEE J Biomed Health Inform ; 25(8): 3073-3081, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33471772

RESUMO

Lung parenchyma segmentation is valuable for improving the performance of lung nodule detection in computed tomography (CT) images. Traditionally, the two tasks are performed separately. This paper proposes a deep multi-task learning (MTL) approach to integrate these tasks for better lung nodule detection. Three new ideas lead to our proposed approach. First, lung parenchyma segmentation is used as the attention module and is combined with nodule detection in a single deep network. Second, lung nodule detection is performed in an anchor-free manner by dividing it into two subtasks, nodule center identification and nodule size regression. Third, a novel pyramid dilated convolution block (PDCB) is proposed to utilize the advantage of dilated convolution and tackle its gridding problem for better lung parenchyma segmentation. Based on these ideas, we design our end-to-end deep network architecture and corresponding MTL method to achieve lung parenchyma segmentation and nodule detection simultaneously. We evaluate the proposed approach on the commonly used Lung Nodule Analysis 2016 (LUNA16) dataset. The experimental results show the value of our contributions and demonstrate that our approach can yield significant improvements compared with state-of-the-art counterparts.


Assuntos
Neoplasias Pulmonares , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia Computadorizada por Raios X
16.
Artigo em Inglês | MEDLINE | ID: mdl-33434002

RESUMO

In this work, we propose a sulfonated poly (ether ether ketone) (SPEEK) composite proton-conductive membrane based on a 3-(1-hydro-imidazolium-3-yl)-propane-1-sulfonate (Him-pS) additive to break through the trade-off between conductivity and selectivity of a vanadium redox flow battery (VRFB). Specifically, Him-pS enables an oriented distribution of the SPEEK matrix to construct highly conductive proton nanochannels throughout the membrane arising from the noncovalent interaction. Moreover, the "acid-base pair" effect from an imidazolium group and a sulfonic group further facilitates the proton transport through the nanochannels. Meanwhile, the structure of the acid-base pair is further confirmed based on density functional theory calculations. Material and electrochemical characterizations indicate that the nanochannels with a size of 16.5 nm are vertically distributed across the membrane, which not only accelerate proton conductivity (31.54 mS cm-1) but also enhance the vanadium-ion selectivity (39.9 × 103 S min cm-3). Benefiting from such oriented proton-conductive nanochannels in the membrane, the cell delivers an excellent Coulombic efficiency (CE, ≈ 98.8%) and energy efficiency (EE, ≈ 78.5%) at 300 mA cm-2. More significantly, the cell maintains a stable energy efficiency over 600 charge-discharge cycles with only a 5.18% decay. Accordingly, this work provides a promising fabrication strategy for a high-performance membrane of VRFB.

17.
Nurs Outlook ; 69(1): 13-21, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32980153

RESUMO

BACKGROUND: The rapidly evolving COVID-19 pandemic has become a global health crisis. Several factors influencing risk perception have been identified, including knowledge of the disease, information sources, and emotional states. Prior studies on COVID-19-related risk perception primarily focused on the general public, with little data available on COVID-19 patients. PURPOSE: To investigate COVID-19 patients' risk perception, knowledge of the disease, information sources, and emotional states in the epicenter, Wuhan, during the COVID-19 outbreak in China. METHODS: Data were collected online using self-administered electronic questionnaire developed with reference to previous relevant studies and publications by the World Health Organization. FINDINGS: A higher level of perceived risk was found in relation to COVID-19 as compared to other potential health threats. Knowledge gaps existed regarding transmission and prevention of COVID-19. Additionally, risk perception was negatively related to knowledge and positively related to depressive states. Moreover, social media was a primary source for COVID-19 information, whereas the most trusted sources were health professionals. DISCUSSION: Realistic perception of risk should be encouraged considering both physical and mental health while developing relevant strategies. Furthermore, risk communication needs to be specifically tailored for various target groups, such as the elderly and mentally vulnerable individuals, with the adoption of popular media platforms.


Assuntos
COVID-19/terapia , Conhecimentos, Atitudes e Prática em Saúde , Pacientes/psicologia , Adulto , Idoso , COVID-19/epidemiologia , China/epidemiologia , Informação de Saúde ao Consumidor/estatística & dados numéricos , Emoções , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes/estatística & dados numéricos , Medição de Risco , Inquéritos e Questionários , Adulto Jovem
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 247: 119029, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33120123

RESUMO

A series of Ag/AgX (X = Cl, Br, I; X = Cl, Br, or X = Cl, I, or X = Br, I; X = Cl, Br, and I) composite photocatalysts were synthesized via a facile photoreduction. The several characterization methods of X-ray diffraction (XRD), energy dispersive X-ray spectrometry (EDS) mapping and X-ray photoelectron spectroscopy (XPS) were characterized the samples. Through evaluation the photocatalytic activity of degradation rhodamine, methyl orange, and phenol, Ag-AgCl1/3Br1/3I1/3 exhibited the superior selective photocatalytic activities than other photocatalysts. The reason for improved photocatalytic property of Ag-AgCl1/3Br1/3I1/3 was attributed to the multifarious halogen atoms with the synergistic effect and the surface plasmon resonance (SPR) effect of Ag0. Furthermore, the recycle experiments were conducted to reveal the stability and reusability, the trapping experiments confirmed the active species of Ag-AgCl1/3Br1/3I1/3.

19.
Nanotechnology ; 32(11): 115501, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33271525

RESUMO

In this paper, a novel ammonia detection hybrid film is proposed based on a graphene oxide (GO)/graphene stack, which shows excellent sensing characteristics at room temperature. It is attributed to the cooperation of GO layer serving as molecular capture layer while graphene serving as conductive layer. GO layer is obtained on chemical vapor deposited graphene film by a simple drop-casting method. The prepared GO/graphene hybrid film is directly transferred to the target substrate without any additional transfer vehicle to reduce possible contamination. The success of the transfer depends on the mechanical strength of GO layer. The thickness of GO layer can scale down to 55 nm while sustaining the transfer process. The best ammonia gas sensing performance is obtained at about 275 nm GO layer thickness and the ammonia detection limit is calculated to be 1.5 ppb. In conclusion, the ammonia gas sensing performance of GO/graphene hybrid film can be significantly improved through GO layer thickness optimization.

20.
Mol Cell Biochem ; 476(2): 797-807, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33095380

RESUMO

Endothelial progenitor cell (EPC) transplantation has shown advantages in the treatment of myocardial infarction (MI) in animal models and clinical trials through mechanisms of direct intercellular contacts, autocrine, and paracrine. However, the effects of EPC transplantation for MI treatment remain controversial and the underlying mechanisms have not been fully elucidated. Here, we explored the role of Rab27a in the therapeutic potential of EPC transplantation in MI. We found that Rab27a knockout impaired the viability, and reduced the proliferation and tube formation function of ECPs. The recovery of cardiac function and improvement of ventricular remodeling from EPCs transplantation were significantly damaged by Rab27a deletion in vivo. Rab27a deletion inhibited the protein expression of phosphoinositide 3-kinase (PI3K) and cyclin D1 and the phosphorylation levels of Akt and FoxO3a. Therefore, Rab27a knockout suppressed the PI3K-Akt-FoxO3a/cyclin D1 signaling pathway. Furthermore, Rab27a ablation dramatically reduced exosome release in EPCs. These results demonstrated that Rab27a plays an essential role in EPC functions. The elucidation of this mechanism provides novel insights into EPC transplantation as a promising treatment for post-MI injuries.

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