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1.
Liver Int ; 44(3): 691-705, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38082504

RESUMO

BACKGROUND AND AIM: Hepatotoxicity is a well-defined reaction to methotrexate (MTX), a drug commonly used for the treatment of rheumatoid arthritis and various tumours. We sought to elucidate the mechanism underlying MTX-induced hepatotoxicity and establish a potentially effective intervention strategy. METHODS: We administered MTX to liver cells and mice and assessed hepatotoxicity by cell viability assay and hepatic pathological changes. We determined ferroptosis and ferritinophagy by detecting ferroptosis-related markers and autophagic degradation of ferritin heavy chain 1 (FTH1). RESULTS: We have shown that hepatocytes treated with MTX undergo ferroptosis, and this process can be attenuated by ferroptosis inhibitors. Interestingly, NCOA4-mediated ferritinophagy was found to be involved in MTX-induced ferroptosis, which was demonstrated by the relief of ferroptosis through the inhibition of autophagy or knockdown of Ncoa4. Furthermore, MTX treatment resulted in the elevation of high-mobility group box 1 (HMGB1) expression. The depletion of Hmgb1 in hepatocytes considerably alleviated MTX-induced hepatotoxicity by limiting autophagy and the subsequent autophagy-dependent ferroptosis. It is noteworthy that glycyrrhizic acid (GA), a precise inhibitor of HMGB1, effectively suppressed autophagy, ferroptosis and hepatotoxicity caused by MTX. CONCLUSION: Our study shows the significant roles of autophagy-dependent ferroptosis and HMGB1 in MTX-induced hepatotoxicity. It emphasizes that the inhibition of ferritinophagy and HMGB1 may have potential as a therapeutic approach for preventing and treating MTX-induced liver injury.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Ferroptose , Proteína HMGB1 , Animais , Camundongos , Autofagia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Metotrexato/toxicidade , Metotrexato/uso terapêutico
2.
Pathobiology ; : 1-13, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38527431

RESUMO

INTRODUCTION: Over the past decade, classifications using immune cell infiltration have been applied to many types of tumors; however, mesotheliomas have been less frequently evaluated. METHODS: In this study, 60 well-characterized pleural mesotheliomas (PMs) were evaluated immunohistochemically for the characteristics of immune cells within tumor microenvironment (TME) using 10 immunohistochemical markers: CD3, CD4, CD8, CD56, CD68, CD163, FOXP3, CD27, PD-1, and TIM-3. For further characterization of PMs, hierarchical clustering analyses using these 10 markers were performed. RESULTS: Among the immune cell markers, CD3 (p < 0.0001), CD4 (p = 0.0016), CD8 (p = 0.00094), CD163+ (p = 0.042), and FOXP3+ (p = 0.025) were significantly associated with an unfavorable clinical outcome. Immune checkpoint receptor expressions on tumor-infiltrating lymphocytes such as PD-1 (p = 0.050), CD27 (p = 0.014), and TIM-3 (p = 0.0098) were also associated with unfavorable survival. Hierarchical clustering analyses identified three groups showing specific characteristics and significant associations with patient survival (p = 0.016): the highest number of immune cells (ICHigh); the lowest number of immune cells, especially CD8+ and CD163+ cells (ICLow); and intermediate number of immune cells (ICInt). ICHigh tumors showed significantly higher expression of PD-L1 (p = 0.00038). Cox proportional hazard model identified ICHigh [hazard ratio (HR) = 2.90] and ICInt (HR = 2.97) as potential risk factors compared with ICLow. Tumor CD47 (HR = 2.36), tumor CD70 (HR = 3.04), and tumor PD-L1 (HR = 3.21) expressions were also identified as potential risk factors for PM patients. CONCLUSION: Our findings indicate immune checkpoint and/or immune cell-targeting therapies against CD70-CD27 and/or CD47-SIRPA axes may be applied for PM patients in combination with PD-L1-PD-1 targeting therapies in accordance with their tumor immune microenvironment characteristics.

3.
Pathol Int ; 74(1): 13-25, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38050808

RESUMO

The present study analyzed the expression of five independent immunohistochemical markers, CD4, CD8, CD66b, CD68, and CD163, on immune cells within the colorectal cancer (CRC) tumor microenvironment (TME). Using hierarchical clustering, patients were successfully classified according to significant associations with clinicopathological features and/or survival. Patients with mismatch repair-proficient (pMMR) CRC were categorized into four groups with survival differences (p = 0.0084): CD4Low , CD4High , MΦHigh , and CD8Low . MΦHigh tumors showed significantly higher expression of CD47 (p < 0.0001), a phagocytosis checkpoint molecule. These tumors contained significantly greater numbers of PD-1+ (p < 0.0001), TIM-3+ (p < 0.0001), and SIRPA+ (p < 0.0001) immune cells. Notably, 10% of the patients with pMMR CRC expressed PD-L1 (CD274) on tumor cells with significantly worse survival (p = 0.00064). The Cox proportional hazards model identified MΦ High (hazard ratio [HR] = 2.02, 95%, p = 0.032), CD8Low (HR = 2.45, p = 0.011), and tumor PD-L1 expression (HR = 2.74, p = 0.0061) as potential risk factors. PD-L1-PD-1 and/or CD47-SIRPA axes targeting immune checkpoint therapies might be considered for patients with pMMR CRC according to their tumor cells and tumor immune microenvironment characteristics.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/patologia , Antígeno CD47 , Antígeno B7-H1/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Biomarcadores Tumorais/análise , Microambiente Tumoral
4.
Int J Mol Sci ; 25(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38473788

RESUMO

Colorectal cancer (CRC) is one of the most common gastrointestinal cancers worldwide, with high morbidity and mortality rates. The evidence for the tumor-supporting capacities of cancer-associated fibroblasts (CAFs) that modulate cancer cell proliferation, invasion, metastasis, and tumor immunity, including in CRC, has been attracting attention. The present study examined the expression status of CD70 and POSTN in CRC and analyzed their association with clinicopathological features and clinical outcomes. In the present study, in total 15% (40/269) and 44% (119/269) of cases exhibited CD70 and POSTN expression on CAFs, respectively. Co-expression of CD70 and POSTN was detected in 8% (21/269) of patients. Fluorescent immunohistochemistry identified the co-expression of CD70 and POSTN with FAP and PDPN, respectively. ACTA2 was not co-expressed with CD70 or POSTN in CRC CAFs. CRC with CD70+/POSTN+ status in CAFs was significantly associated with distant organ metastasis (p = 0.0020) or incomplete resection status (p = 0.0011). CD70+/POSTN+ status tended to associate with advanced pT stage (p = 0.032) or peritoneal metastasis (p = 0.0059). Multivariate Cox hazards regression analysis identified CD70+/POSTN+ status in CAFs [hazard ratio (HR) = 3.78] as a potential independent risk factor. In vitro experiments revealed the activated phenotypes of colonic fibroblasts induced by CD70 and POSTN, while migration and invasion assays identified enhanced migration and invasion of CRC cells co-cultured with CD70- and POSTN-expressing colonic fibroblasts. On the basis of our observations, CD70 and POSTN immunohistochemistry can be used in the prognostication of CRC patients. CRC CAFs may be a promising target in the treatment of CRC patients.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Colorretais , Humanos , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos/metabolismo , Imuno-Histoquímica , Proliferação de Células , Neoplasias Colorretais/patologia , Moléculas de Adesão Celular/metabolismo , Ligante CD27/metabolismo
5.
Electrophoresis ; 43(15): 1601-1610, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35405037

RESUMO

Prolyl hydroxylase domain 2 (PHD2) is a key enzyme regulating the expression of hypoxia inducible factor (HIF). Its inhibitors can improve the expression of HIF and downstream genes, which can treat hypoxia-related diseases. Therefore, the establishment of a reliable PHD2 inhibitors screening method is of great significance for the drug development of hypoxia-related diseases. In this work, an accurate, rapid, and simple screening method for PHD2 inhibitors was introduced by capillary zone electrophoresis (CZE). In order to improve the detection sensitivity, the derivative reaction of α-ketoglutaric acid (α-OG) and 1,2-diaminobenzene (OPD) was used to enhance the UV absorption of α-OG (the substrate in the enzymatic reaction). The CZE method selected 20 mM Na2 B4 O7 buffer (pH 9.0) as the separation buffer, +25 kV as the separation voltage, 25°C as the cartridge temperature, and 210 nm as the detection wavelength. Under this condition, the analysis of a single sample can be realized within 9 min. Compared with the existing reported methods, the present work can directly screen the PHD2 inhibitory activity of traditional Chinese medicine (TCM) extracts, which is of significance for the target-purification of bioactive individual compounds from TCMs. Under the optimal conditions, the PHD2 inhibitor screening platform was successfully established, and it was found that 70% methanol/water extracts of Astragali Radix and Codonopsis pilosula had good PHD2 inhibitory activity. Furthermore, the present work provides a novel approach for screening the PHD2 inhibitory activity of TCM extracts and the discovery of anti-hypoxia bioactive compounds.


Assuntos
Prolina Dioxigenases do Fator Induzível por Hipóxia , Medicina Tradicional Chinesa , Eletroforese Capilar , Humanos , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia , Prolina Dioxigenases do Fator Induzível por Hipóxia/química , Prolina Dioxigenases do Fator Induzível por Hipóxia/genética , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Pró-Colágeno-Prolina Dioxigenase/genética , Pró-Colágeno-Prolina Dioxigenase/metabolismo
6.
Toxicol Appl Pharmacol ; 448: 116092, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35654276

RESUMO

Gypenosides are major bioactive ingredients of G. pentaphyllum. In our previous study, we found that gypenosides had neuroprotective effects against hypoxia-induced injury. In the current study, we focused on the protective effects of gypenoside-14 (GP-14), which is one of the newly identified bioactive components, on neuronal injury caused by severe hypoxia (0.3% O2). The results showed that GP-14 pretreatment alleviated the cell viability damage and apoptosis induced by hypoxia in PC12 cells. Moreover, GP-14 pretreatment also attenuated primary neuron injuries under hypoxic conditions. Additionally, GP-14 pretreatment significantly ameliorated neuronal damage in the hippocampal region induced by high-altitude cerebral edema (HACE). At the molecular level, GP-14 pretreatment reversed the decreased activities of the AKT and ERK signaling pathways caused by hypoxia in PC12 cells and primary neurons. To comprehensively explore the possible mechanisms, transcriptome sequencing was conducted, and these results indicated that GP-14 could alter the transcriptional profiles of primary neuron. Taken together, our results suggest that GP-14 acts as a neuroprotective agent to protect against neuronal damage induced by severe hypoxia and it is a promising compound for the development of neuroprotective drugs.


Assuntos
Sistema de Sinalização das MAP Quinases , Neurônios , Fármacos Neuroprotetores , Proteínas Proto-Oncogênicas c-akt , Animais , Apoptose/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Perfilação da Expressão Gênica , Gynostemma/química , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos
7.
J Clin Lab Anal ; 36(12): e24787, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36441597

RESUMO

BACKGROUND: To examine the association between low-density lipoprotein cholesterol (LDL-C) concentrations and the risk of a large hematoma volume after intracerebral hemorrhage (ICH). METHODS: Patients from the Kailuan study (Tangshan, China) who were hospitalized with ICH during 2006 and 2020 were included in this study. The concentration of lipid concentrations, hematoma volume and other clinical characteristics were retrospectively collected and analyzed. Hematoma volumes were measured on the first available brain scan using the ABC/2 method. LDL-C concentrations were obtained from the last physical examination before the occurrence of ICH. LDL-C concentration was categorized into four groups in accordance with the quartiles. Logistic regression was used to assess the association between LDL-C concentrations and the risk of a large hematoma volume of ≥30 ml. A generalized linear regression model was used to analyze the dose-response relationship between LDL-C concentration and hematoma volume. RESULTS: A total of 836 patients with ICH were evaluated. In the Multivariate logistic regression, compared to the second quartile of LDL_C, the first quartile of LDL_C had a significantly higher risk of a large hematoma volume (OR 2.49 [95% CI 1.54-4.01]), and the higher quartile of LDL_C is not associated with higher odds of large hematoma volume. In the generalized linear regression model, the adjusted ß for the association between LDL-C concentration and hematoma volume was 9.46 (95% confidence interval 2.87-16.04), whereas higher LDL-C concentration was not associated with a large hematoma volume. CONCLUSIONS: This study confirmed that low LDL-C concentrations prior to ICH are associated with a higher risk of a large hematoma volume.


Assuntos
Hemorragia Cerebral , Hematoma , Humanos , LDL-Colesterol , Estudos Retrospectivos , Hemorragia Cerebral/epidemiologia , Hemorragia Cerebral/complicações , Hematoma/etiologia , Hematoma/complicações , Neuroimagem
8.
Mikrochim Acta ; 189(11): 436, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36319898

RESUMO

As a prodrug-converting enzyme, ß-glucuronidase (ß-GCase) is a lysosomal enzyme participating in the release of glucose from glucopyranosyl glycoside. In this work, for the first time, we have developed an analytical method exhibiting fluorometric signals for straightforward determination of ß-GCase using silicon nanoparticles (Si NPs). Via hydrothermal treatment, in the water bath of 70 °C for 50 min, dopamine (DA) reacts with (3-[2-(2-aminoethylamino) ethylamino] propyltrimethoxysilane) (AEEA) to produce green fluorescent Si NPs. Enlightened by such easy reaction and ß-GCase-triggered specific hydrolysis of dopamine-4-ß-D-glucuronide (DA-GCU) into DA, we have designed an analytical method for ß-GCase sensing through the production of Si NPs. Therefore, through the designed sensing platform, ß-GCase activity was monitored, and the limit of detection (LOD) for this study was 0.02 U/L. Furthermore, the feasibility of the method was assessed by measuring ß-GCase activity in human serum where recoveries and RSD were in the ranges 99-104% and 1.37-3.44, respectively.


Assuntos
Nanopartículas , Silício , Humanos , Glucuronidase , Dopamina , Fluorometria/métodos
9.
Sensors (Basel) ; 22(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36501871

RESUMO

The large view angle and complex background of UAV images bring many difficulties to the detection of small pedestrian targets in images, which are easy to be detected incorrectly or missed. In addition, the object detection models based on deep learning are usually complex and the high computational resource consumption limits the application scenarios. For small pedestrian detection in UAV images, this paper proposes an improved YOLOv5 method to improve the detection ability of pedestrians by introducing a new small object feature detection layer in the feature fusion layer, and experiments show that the improved method can improve the average precision by 4.4%, which effectively improves the pedestrian detection effect. To address the problem of high computational resource consumption, the model is compressed using channel pruning technology to reduce the consumption of video memory and computing power in the inference process. Experiments show that the model can be compressed to 11.2 MB and the GFLOPs of the model are reduced by 11.9% compared with that before compression under the condition of constant inference accuracy, which is significant for the deployment and application of the model.


Assuntos
Pedestres , Humanos , Tecnologia
10.
Sensors (Basel) ; 22(9)2022 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-35590959

RESUMO

Compared with hyperpolarized noble gas MRI, oxygen-enhanced lung imaging is a cost-effective approach to investigate lung function. In this study, we investigated the feasibility of free-breathing phase-resolved oxygen-enhanced pulmonary MRI based on a 3D stack-of-stars ultra-short echo time (UTE) sequence. We conducted both computer simulation and in vivo experiments and calculated percent signal enhancement maps of four different respiratory phases on four healthy volunteers from the end of expiration to the end of inspiration. The phantom experiment was implemented to verify simulation results. The respiratory phase was segmented based on the extracted respiratory signal and sliding window reconstruction, providing phase-resolved pulmonary MRI. Demons registration algorithm was applied to compensate for respiratory motion. The mean percent signal enhancement of the average phase increases from anterior to posterior region, matching previous literature. More details of pulmonary tissues were observed on post-oxygen inhalation images through the phase-resolved technique. Phase-resolved UTE pulmonary MRI shows the potential as a valuable method for oxygen-enhanced MRI that enables the investigation of lung ventilation on middle states of the respiratory cycle.


Assuntos
Imageamento Tridimensional , Oxigênio , Simulação por Computador , Humanos , Imageamento Tridimensional/métodos , Pulmão/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Respiração
11.
Molecules ; 27(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36364344

RESUMO

The occurrence and development of neurodegenerative diseases is related to a variety of physiological and pathological changes. Neuroinflammation is one of the major factors that induces and aggravates neurodegenerative diseases. The most important manifestation of neuroinflammation is the activation of microglia. Therefore, inhibiting the abnormal activation of microglia is an important way to alleviate the occurrence of neuroinflammatory diseases. In this research, the inhibitory effect of tabersonine (Tab) on neuroinflammation was evaluated by establishing the BV2 neuroinflammation model induced by lipopolysaccharide (LPS). It was found that Tab significantly inhibited the production and expression of nitric oxide (NO), interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and reactive oxygen species (ROS) in BV-2 cells stimulated by LPS. In addition, Tab can also inhibit the activation of nuclear factor-κB (NF-κB) induced by LPS, thus regulating inflammatory mediators such as inducible nitric oxide synthase (iNOS). These results indicated that Tab regulated the release of inflammatory mediators such as NO, IL-1ß, TNF-α, and IL-6 by inhibiting NF-κB signaling pathway, and exerting its anti-neuroinflammatory effect. This is the first report regarding the inhibition on LPS-induced neuroinflammation in BV2 microglia cells of Tab, which indicated the drug development potential of Tab for the treatment of neurodegenerative diseases.


Assuntos
Lipopolissacarídeos , NF-kappa B , Humanos , NF-kappa B/metabolismo , Lipopolissacarídeos/farmacologia , Microglia , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Anti-Inflamatórios/uso terapêutico , Óxido Nítrico Sintase Tipo II/metabolismo , Transdução de Sinais , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Óxido Nítrico/metabolismo
12.
Molecules ; 27(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36364317

RESUMO

Natural products (NPs) were a rich source of diverse bioactive molecules. Most anti-tumor agents were built on natural scaffolds. Nardostachys jatamansi DC. was an important plant used to process the traditional Chinese herbal medicines "gansong". Pancreatic cancer was the fourth most common cause of cancer-related death in the world. Hence, there was an urgent need to develop novel agents for the treatment of pancreatic cancer. In this paper, nardoguaianone L (G-6) is isolated from N. jatamansi, which inhibited SW1990 cells colony formation and cell migration, and induced cell apoptosis. Furthermore, we analyzed the differential expression proteins after treatment with G-6 in SW1990 cells by using iTRAQ/TMT-based quantitative proteomics technology, and the results showed that G-6 regulated 143 proteins' differential expression by GO annotation, including biological process, cellular component, and molecular function. Meanwhile, KEGG enrichment found that with Human T-cell leukemia virus, one infection was the most highly enhanced pathway. Furthermore, the MET/PTEN/TGF-ß pathway was identified as a significant pathway that had important biological functions, including cell migration and motility by PPI network analysis in SW1990 cells. Taken together, our study found that G-6 is a potential anti-pancreatic cancer agent with regulation of MET/PTEN/TGF-ß pathway.


Assuntos
Nardostachys , Neoplasias , Humanos , Apoptose , Fator de Crescimento Transformador beta
13.
Anal Chem ; 93(46): 15412-15419, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34762397

RESUMO

Designing analytical approaches for enzymatic activity monitoring with high sensitivity and selectivity is of critical value for the diagnosis of diseases and biomedical studies. In this study, we have created a facile one-step synthetic route to prepare orange-red color and yellow fluorescent silicon-containing nanoparticles (Si CNPs) by mixing 3(2-aminoethylamino) propyl (dimethoxymethylsilane) and hydroquinone (HQ) in an aqueous solution. Inspired by the HQ-regulated facile synthetic step and the generation of HQ from α-glucosidase (α-Glu)-catalyzed hydrolysis of 4-hydroxyphenyl-α-d-glucopyranosyl (4-HPαDG), we have designed a straightforward colorimetric and fluorometric α-Glu activity assay using a commercially available 4-HPαDG as the α-Glu substrate. Fluorescent and colorimetric assays for α-Glu activity measurement have been thereby established and exhibited detection limits as low as 0.0032 and 0.0046 U/mL, respectively. Under single excitation at 370 nm, the prepared Si CNPs emitted yellow fluorescence at 520 nm and exhibited an absorbance peak at 390 nm. In addition, the proposed approach reveals various advantages including easy operation, time-saving, and good anti-interference ability. Hence, it could improve the progress of fluorometric and colorimetric enzymatic activity assays with high sensitivity and simplicity. Moreover, the proposed approach was applied for α-Glu inhibitor screening, and its feasibility in real samples was measured by detecting the α-Glu activity in human serum samples.


Assuntos
Colorimetria , Nanopartículas , Corantes Fluorescentes , Humanos , Silício , alfa-Glucosidases
14.
J Org Chem ; 86(16): 11006-11010, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-33326231

RESUMO

Narjatamolide (1), an unusual homoguaiane sesquiterpene lactone, was isolated from the roots and rhizomes of Nardostachys jatamansi DC. It represents the new carbon skeleton of a homoguaiane sesquiterpenoid possessing an additional acetate unit spiro-fused with C-4 and C-15 to form a cyclopropane ring. The structure of 1 was elucidated by extensive spectroscopic analyses, and the absolute configuration was confirmed by the electronic circular dichroism (ECD) calculations and X-ray single-crystal diffraction analysis. Compound 1 showed antiproliferative effects against BEL-7402 cell lines with an IC50 value of 5.67 ± 1.43 µM, and the mechanism study showed that 1 induces cell cycle of BEL-7402 cell lines arrest at G2/M phase.


Assuntos
Nardostachys , Sesquiterpenos , Lactonas/farmacologia , Estrutura Molecular , Rizoma , Sesquiterpenos/farmacologia
15.
Biotechnol Appl Biochem ; 68(1): 41-51, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31981375

RESUMO

Cynomorium songaricum Rupr is widely known in China as a traditional herbal medicine. In this study, single-factor experiments and response surface methodology were used to optimize the extraction of Cynomorium songaricum Rupr glycoprotein (CSG). The results show that a maximum glycoprotein yield of 6.39 ± 0.32% was achieved at a ratio of solid to liquid 32:1 for 4.2 H at 52 °C. Then, the IR, monosaccharide composition, amino acid composition, type of glycopeptide linkage, and average molecular weight of CSG-1 purified from CSG were characterized. The results indicate that CSG-1 presented the characteristic absorption peak of polysaccharide and protein, including four monosaccharides and 17 amino acids, had O-linked glycopeptide bonds, Mw , Wn , Mw /Mn , Mp , and the z-average were 5.343 × 106 , 3.203 × 106 , 1.668, 8.911 × 106 , and 6.948 × 106 , respectively. Besides, CSG-1 solution was described by the Herschel-Bulkley model and it behaved as a shear-thinning fluid. Also, under a frequency sweep the moduli G' and G″ both increased with increasing CSG-1 concentration and the CSG-1 dispersions had weak thermal stability over the temperature sweep. These results provide a scientific basis for the further study of Cynomorium songaricum Rupr.


Assuntos
Cynomorium/química , Glicoproteínas , Proteínas de Plantas , Glicoproteínas/química , Glicoproteínas/isolamento & purificação , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Reologia
16.
Sensors (Basel) ; 21(14)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34300648

RESUMO

Real-time collision-avoidance navigation of autonomous ships is required by many application scenarios, such as carriage of goods by sea, search, and rescue. The collision avoidance algorithm is the core of autonomous navigation for Maritime autonomous surface ships (MASS). In order to realize real-time and free-collision under the condition of multi-ship encounter in an uncertain environment, a real-time collision avoidance framework is proposed using B-spline and optimal decoupling control. This framework takes advantage to handle the uncertain environment with limited sensing MASS which plans dynamically feasible, highly reliable, and safe feasible collision avoidance. First, owing to the collision risk assessment, a B-spline-based collision avoidance trajectory search (BCATS) algorithm is proposed to generate free-collision trajectories effectively. Second, a waypoint-based collision avoidance trajectory optimization is proposed with the path-speed decoupling control. Two benefits, a reduction of control cost and an improvement in the smoothness of the collision avoidance trajectory, are delivered. Finally, we conducted an experiment using the Electronic Chart System (ECS). The results reveal the robustness and real-time collision avoidance trajectory planned by the proposed collision avoidance system.


Assuntos
Algoritmos , Medição de Risco
17.
Radiology ; 297(1): 201-210, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32779976

RESUMO

Background Apparent diffusion coefficient (ADC) maps of inhaled hyperpolarized gases have shown promise in the characterization of emphysema in patients with chronic obstructive pulmonary disease (COPD), yet an easily interpreted quantitative metric beyond mean and standard deviation has not been established. Purpose To introduce a quantitative framework with which to characterize emphysema burden based on hyperpolarized helium 3 (3He) and xenon 129 (129Xe) ADC maps and compare its diagnostic performance with CT-based emphysema metrics and pulmonary function tests (PFTs). Materials and Methods Twenty-seven patients with mild, moderate, or severe COPD and 13 age-matched healthy control subjects participated in this retrospective study. Participants underwent CT and multiple b value diffusion-weighted 3He and 129Xe MRI examinations and standard PFTs between August 2014 and November 2017. ADC-based emphysema index was computed separately for each gas and b value as the fraction of lung voxels with ADC values greater than in the healthy group 99th percentile. The resulting values were compared with quantitative CT results (relative lung area <-950 HU) as the reference standard. Diagnostic performance metrics included area under the receiver operating characteristic curve (AUC). Spearman rank correlations and Wilcoxon rank sum tests were performed between ADC-, CT-, and PFT-based metrics, and intraclass correlation was performed between repeated measurements. Results Thirty-six participants were evaluated (mean age, 60 years ± 6 [standard deviation]; 20 women). ADC-based emphysema index was highly repeatable (intraclass correlation coefficient > 0.99) and strongly correlated with quantitative CT (r = 0.86, P < .001 for 3He; r = 0.85, P < .001 for 129Xe) with high AUC (≥0.93; 95% confidence interval [CI]: 0.85, 1.00). ADC emphysema indices were also correlated with percentage of predicted diffusing capacity of lung for carbon monoxide (r = -0.81, P < .001 for 3He; r = -0.80, P < .001 for 129Xe) and percentage of predicted residual lung volume divided by total lung capacity (r = 0.65, P < .001 for 3He; r = 0.61, P < .001 for 129Xe). Conclusion Emphysema index based on hyperpolarized helium 3 or xenon 129 diffusion MRI provides a repeatable measure of emphysema burden, independent of gas or b value, with similar diagnostic performance as quantitative CT or pulmonary function metrics. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Schiebler and Fain in this issue.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Enfisema Pulmonar/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Estudos de Casos e Controles , Feminino , Hélio , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória , Isótopos de Xenônio
18.
BMC Infect Dis ; 19(1): 925, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666015

RESUMO

BACKGROUND: Ruili is a border city in southwest China along the heroin trafficking route. In recent decades, the city has witnessed increased in HIV transmission. The current study aims to explore the spatiotemporal trends in HIV prevalence identify and map the spatial variation and clustering of factors associated with HIV transmission through drug use and heterosexual contact transmissions at the village level from 1989 through 2016. METHODS: Geographic information system-based spatiotemporal analyses, including global and local spatial autocorrelation analyses and space-time scanning statistics, were applied to detect the location and extent of HIV/AIDS high-risk areas. RESULTS: Drug use and heterosexual contact were identified as the major transmission routes causing infection in Ruili. Results of global spatial analysis showed significant clustering throughout the city caused by transmission via drug use in the early phase of the epidemic and transmission via heterosexual contact in the late phase of the epidemic during the study period. Hotspots of transmission from drug use were randomly distributed throughout the city. However, the hotspots of transmission by heterosexual contact were located in the central area only around the Jiegao China-Myanmar land port. Space-time scanning showed that transmission from drug use clustered in the southwest area between 1989 and 1990, while transmission by heterosexual contact clustered in the central area between 2004 and 2014. CONCLUSIONS: Heterosexual contact has become the dominant mode of transmission. Interventions should focus on highly clustered area where is around the Jiegao land port.


Assuntos
Infecções por HIV/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/transmissão , Adulto , China/epidemiologia , Cidades , Análise por Conglomerados , Epidemias , Feminino , Sistemas de Informação Geográfica , Infecções por HIV/transmissão , Heterossexualidade , Humanos , Masculino , Mianmar , Prevalência , Comportamento Sexual , Análise Espaço-Temporal , Transtornos Relacionados ao Uso de Substâncias/virologia
19.
Int J Med Sci ; 16(4): 529-536, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31171904

RESUMO

Epithelial-mesenchymal transition (EMT), which involves the dramatic reorganization of the cytoskeleton, is a crucial initiating step in tumor invasion and metastasis. Protein 4.1B is a membrane-cytoskeleton cross-linker that plays an important role in tumor progression and metastasis; however, the functional roles of 4.1B in melanoma remain unclear. In this study, we aimed to investigate the effect and underlying mechanism of 4.1B on melanoma cells. Our results demonstrated that 4.1B expression was downregulated in murine B16 and B16-F10 melanoma cell lines. Ectopic 4.1B expression significantly inhibited the migration of melanoma cells and pulmonary metastasis. We further investigated the possible mechanism underlying the effect of 4.1B on EMT. The results showed that ectopic 4.1B expression altered the expression of representative EMT markers (E-cadherin, vimentin and N-cadherin), and inhibited the expression of three important transcription factors (Slug, Snail, and Twist) related to EMT in melanoma cells. Moreover, the expression of integrin α5, ß3 and matrix metalloproteinase 9 (MMP-9), which is known to regulate cell adhesion, migration and invasion, were suppressed. In conclusion, our data indicate that 4.1B is an important regulator during EMT progression in melanoma cells, which may present a potential target for the prevention and treatment of melanoma.


Assuntos
Neoplasias Pulmonares/genética , Melanoma Experimental/genética , Proteínas dos Microfilamentos/genética , Proteínas de Neoplasias/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Citoesqueleto/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Metaloproteinase 9 da Matriz/genética , Melanoma Experimental/patologia , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Metástase Neoplásica
20.
Sensors (Basel) ; 19(18)2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31546977

RESUMO

This research focuses on the adaptive navigation of maritime autonomous surface ships (MASSs) in an uncertain environment. To achieve intelligent obstacle avoidance of MASSs in a port, an autonomous navigation decision-making model based on hierarchical deep reinforcement learning is proposed. The model is mainly composed of two layers: the scene division layer and an autonomous navigation decision-making layer. The scene division layer mainly quantifies the sub-scenarios according to the International Regulations for Preventing Collisions at Sea (COLREG). This research divides the navigational situation of a ship into entities and attributes based on the ontology model and Protégé language. In the decision-making layer, we designed a deep Q-learning algorithm utilizing the environmental model, ship motion space, reward function, and search strategy to learn the environmental state in a quantized sub-scenario to train the navigation strategy. Finally, two sets of verification experiments of the deep reinforcement learning (DRL) and improved DRL algorithms were designed with Rizhao port as a study case. Moreover, the experimental data were analyzed in terms of the convergence trend, iterative path, and collision avoidance effect. The results indicate that the improved DRL algorithm could effectively improve the navigation safety and collision avoidance.

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