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1.
J Cardiothorac Surg ; 15(1): 303, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028380

RESUMO

OBJECTIVE: To investigate whether video-assisted thoracoscopic segmentectomy using near-infrared fluorescence imaging had better intersegmental plane visualization and peri-operative outcome in patients with chronic lung diseases. METHODS: Data were collected retrospectively from March 2014 and August 2019. A total of 92 patients with pulmonary nodules underwent near-infrared fluorescence guided uni-port thoracoscopic segmentectomy(NIF-VATS), 149 patients underwent thoracoscopic segmentectomy with inflation-deflation method(ID-VATS). After 1:1 propensity matching, perioperative outcomes between NIF-VATS and ID-VATS was compared. RESULTS: Incision size was 3 cm in both group.Mean operative time was 79 min in NIF-VATS group and 96 min in ID-VATS group. The intersegmental plane was not clear in 33 cases of ID-VATS group, and no clear boundary was found after prolonged waiting time. Emphysema or pulmonary bullae could be found in chest CT scan in these patients, they all were diagnosed as chronic obstructive pulmonary disease. In NIF-VATS group, the intersegmental plane was not clear in 8 cases. Under the guidance of three-dimensional reconstruction and preoperative positioning, the oncological margin length of both groups met the requirements of surgical quality control. The intraoperative blood loss, number of lymph node resection, showed no statistical difference between the two groups. Postoperative air leakage was more often observed in ID-VATS group. The postoperative drainage duration, postoperative hospitalization time was shorter in ID-VATS group. CONCLUSIONS: Compared with inflation-deflation method, segmentectomy using NIF imaging is feasible for patients with chronic lung diseases with better intersegmental plane, shorter operation time, less complications, it might lead to faster recovery.

2.
Nanoscale ; 12(40): 20883-20889, 2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33048076

RESUMO

DNA walking machines have been widely used in rapid and sensitive detection. In this work, we develop a single enzyme-powered DNA cascade machine for the ultrasensitive determination of kanamycin. To construct the cascade manner, two types of single-legged three-dimensional DNA walking machine are employed to implement integrated target recognition, signal transduction and signal amplification. Upon adding kanamycin to trigger the upstream machine, the sequential enzymatic cleavage drives the autonomous movement of the walking strand and produces plenty of dye-labeled fragments with fluorescence recovery. Meanwhile, these fragments also serve as walking strands to activate the downstream machine for cascade signal amplification. Taking advantage of this cascade DNA machine, ultrasensitive determination can be accomplished in 60 min. Under the optimum conditions, this method was highly selective toward kanamycin with a detection limit of 28 fM. This cascade signal amplification shows great potential for the rapid screening of antibiotics in food.

3.
Can J Microbiol ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33022188

RESUMO

To understand the diversities of diazotrophs and denitrifiers in red paddy soil under long-term fertilization conditions, nifH, nirK and nosZ libraries were constructed based on the PCR-RFLP method. nirK gene diversity proved to be lower than that of nosZ and nifH, and nirK and nosZ genes were more sensitive to different fertilization treatments than those with the nifH gene. Diverse microbes including the α-, ß-, γ- and δ- subclasses of the Proteobacteria dominated the three libraries. Long-term addition of urea with straw-mulching and azophoska increased the abundance of non-symbiotic diazotrophs, which indicated that non-symbiotic diazotrophs were responsible for the majority of the nitrogen-fixing ability in paddy soil. In addition, a potential link between nifH and nosZ was found due to the existence of nitrogen fixers, such as Bradyrhizobium and Ralstonia in the nosZ library. The main chemical factors affecting the three genes were identified, pH was the most important factor of nifH community, and nirK genes were more affected by pH and organic matter, available potassium and carbon to nitrogen ratio significantly influenced the community structure of the nosZ genes.

4.
Dis Markers ; 2020: 4763492, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33014187

RESUMO

Background: Neuropilin 1 (NRP1) is involved in tumorigenesis, development, invasion, and metastasis by promoting angiogenesis of tumors. The study is aimed at evaluating the correlation between the expression of NRP1 protein and clinicopathological features of gastric cancer by meta-analysis. Methods: The published studies were searched in databases including CNKI, Wanfang, Chongqing VIP, Web of Science, and PubMed online. Clinical case studies were included to compare the correlation between NRP1 protein expression and clinicopathological characteristics of gastric cancer. The quality of the included literatures was evaluated by NOS scale. Meta-analysis was performed by Stata software to calculate the odds ratio (OR) and 95% confidence interval (CI). Results: A total of 12 studies were included in this analysis, involving 1,225 patients with gastric cancer. The analysis indicated that the expression of NRP1 protein in gastric cancer tissues was lower in the group of early stage versus advanced stage (OR = 0.128, 95%CI = 0.059 - 0.277, P ≤ 0.001), tumor size less than 5 cm versus more than 5 cm (OR = 0.443, 95%CI = 0.310 - 0.632, P ≤ 0.001), TNM stage I-II group versus stage III-IV patients (OR = 0.736, 95%CI = 0.589 - 0.919, P = 0.007), well to medium differentiation group versus poor differentiation group (OR = 0.735, 95%CI = 0.632 - 0.854, P ≤ 0.001), and nonlymph node metastasis group versus lymph node metastasis group (OR = 0.667, 95%CI = 0.522 - 0.854, P ≤ 0.001). The expression of NRP1 protein in gastric cancer was not related to gender, age, and Laurèn's classification. Conclusion: The expression of NRP1 protein in gastric cancer is closely correlated to clinical stage, tumor size, TNM stage, differentiation, and lymph node metastasis.

5.
Infect Dis Poverty ; 9(1): 143, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33076968

RESUMO

BACKGROUND: Effective management of imported cases is an important part of epidemic prevention and control. Hainan Province, China reported 168 coronavirus disease 2019 (COVID-19), including 112 imported cases on February 19, 2020, but successfully contained the epidemic within 1 month. We described the epidemiological and clinical characteristics of COVID-19 in Hainan and compared these features between imported and local cases to provide information for other international epidemic areas. METHODS: We included 91 patients (56 imported and 35 local cases) from two designated hospitals for COVID-19 in Haikou, China, from January 20 to February 19, 2020. Data on the demographic, epidemiological, clinical and laboratory characteristics were extracted from medical records. Patients were followed until April 21, 2020, and the levels of antibodies at the follow-ups were also analysed by the Wilcoxon matched-pairs signed ranks test. RESULTS: Of the 91 patients, 78 (85.7%) patients were diagnosed within the first three weeks after the first case was identified (Day 1: Jan 22, 2020), while the number of local cases started to increase during the third week. No new cases occurred after Day 29. Fever and cough were two main clinical manifestations. In total, 15 (16.5%) patients were severe, 14 (15.4%) had complicated infections, nine (9.9%) were admitted to the intensive care unit, and three died. The median duration of viral shedding in feces was longer than that in nasopharyngeal swabs (19 days vs 16 days, P = 0.007). Compared with local cases, imported cases were older and had a higher incidence of fever and concurrent infections. There was no difference in outcomes between the two groups. IgG was positive in 92.8% patients (77/83) in the follow-up at week 2 after discharge, while 88.4% patients (38/43) had a reduction in IgG levels in the follow-up at week 4 after discharge, and the median level was lower than that in the follow-up at week 2 (10.95 S/Cut Off (S/CO) vs 15.02 S/CO, P <  0.001). CONCLUSION: Imported cases were more severe than local cases but had similar prognoses. The level of IgG antibodies declined from week 6 to week 8 after onset. The short epidemic period in Hainan suggests that the epidemic could be quickly brought under control if proper timely measures were taken.

6.
J Diabetes Complications ; 34(9): 107622, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33051005

RESUMO

Diabetic foot ulcers are among the most serious complications of diabetes. If left untreated, these ulcers can lead to severe infection and gangrene; in some instances, they may result in death. Thus, timely treatment of diabetic foot ulcers is extremely important. However, timely patient treatment during the COVID-19 pandemic is particularly challenging, because of the higher volume of patients and the need to ensure safety of medical personnel. This article describes a proposed strategy for diagnosis and treatment of diabetic foot ulcers, based on experiences with infection and control strategies during the COVID-19 pandemic in China.

7.
World J Microbiol Biotechnol ; 36(12): 176, 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33103226

RESUMO

Nerve growth factor (NGF) is an essential trophic factor for the growth and survival of neurons in the central and peripheral nervous systems. For many years, mouse NGF (mNGF) has been used to treat various neuronal and non-neuronal disorders. However, the biological activity of human NGF (hNGF) is significantly higher than that of mNGF in human cells. Using the CRISPR/Cas9 system, we constructed the transgenic mice expressing hNGF specifically in their submandibular glands. As demonstrated by fluorescence immunohistochemical staining, these mice produced hNGF successfully, with 0.8 mg produced per gram of submandibular glands. hNGF with 99% purity was successfully extracted by two-step ion-exchange chromatography and one-step size-exclusion chromatography from the submandibular glands of these transgenic mice. Further, the purified hNGF was verified by LC-MS/MS. We analyzed the NH2-terminus of hNGF using both Edman degradation and LC-MS/MS-based methods. Both results showed that the obtained hNGF lost the NH2-terminal octapeptide (SSSHPIFH). Moreover, the produced hNGF demonstrated a strong promotion in the proliferation of TF1 cells.

8.
Artigo em Inglês | MEDLINE | ID: mdl-32918261

RESUMO

A 3-year field experiment was conducted to evaluate the accumulation ability of 3 forage mulberry (Morus atropurpurea Roxb.) varieties (Guisangyou 62, Guisangyou 12, Yuesang 11) for Cadmium (Cd). The results showed that the shoot biomass of forage mulberry could reach to 64.51~69.58 t/ha in 2018. The total production of Guisangyou 12 was the highest among the tested 3 cultivars in each year. However, the biomass of the 3 varieties displayed without significant differences at every sampling time. In addition, the concentrations of Cd in the roots of the 3 mulberry cultivars were higher than those in the corresponding shoots in 2018. But in 2019, the Cd content in roots was near to that of shoots. The Cd concentrations in the roots of the forage mulberry showed Guisangyou 62 > Yuesang 11 > Guisangyou 12. And the Cd concentrations in shoots of all the 3 tested forage mulberry varieties were less than 1 mg/kg, meeting the hygienical standard for feeds (China). Though the 3 forage mulberry varieties were not hyperaccumulators for Cd, they could be used as alternative plants to make use of the Cd-polluted (< 1.0 mg/kg) paddy soils.

9.
Int J Med Mushrooms ; 22(7): 693-703, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32865926

RESUMO

There have been few studies on the cosmetic efficacy of Coprinus comatus, Cordyceps militaris, and Pleurotus geesteranus. This article aims to compare the cosmetic effects of the mycelium, fermentation broth, and mycelium and fermentation broth mixture of liquid-fermented C. comatus, C. militaris, and P. geesteranus. Our results verified that these three edible mushrooms all showed excellent antioxidant, moisturizing, and whitening effects. Comparatively, we found that the cosmetic effects of C. comatus were superior to C. militaris and P. geesteranus. Therefore, we speculate that among the three edible mushrooms, C. comatus will be the most suitable to be used as a basis for cosmeceutical formulations to tackle skin aging and hyperpigmentation. This research aims to provide a basis for the study of the cosmetic effects of edible mushrooms.

10.
ISME J ; 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887945

RESUMO

Coculture is an important model system in microbial ecology studies. As a key experimental parameter, the initial inoculation ratio has a crucial impact on the results of the coculture system. However, such an effect has never been investigated under multiple niche conditions. In this study, we established a simple coculture system with two model bacteria in various carbon sources and investigated the influence of initial inoculum ratios of 1:1000 to 1000:1 on community structure, function, and bacterial interaction. We found that the final ratio of the cocultures with different initial inoculum ratios differed in approximately five-sixths of the carbon sources, suggesting that the final ratio is highly dependent on the initial inoculum ratio, while the carbon source preferences of bacteria could not predict the final ratio of cocultures. Furthermore, we found that the initial ratio could regulate the metabolic capacity of the coculture, as only cocultures with initial ratios of 1:1 and 1000:1 gained high capacity on 14 specific carbon sources. The underlying reason may be that the pattern of species interaction is changed by the initial ratio. In conclusion, we showed that the initial ratio can induce emergent properties in coculture. These findings suggest that the initial ratio not only impacts the reproducibility of coculture experiments but also can influence our understanding of generic microbial ecology.

11.
EBioMedicine ; 60: 103016, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32980695

RESUMO

BACKGROUND: The risk of recurrence in localised, primary gastrointestinal stromal tumour (GIST) classified as high-risk after complete resection varies significantly. Thus, we aimed to develop a nomogram to predict the recurrence of high-risk GIST after surgery to aid patient selection. METHODS: We retrospectively evaluated patients (n = 424) with high-risk GIST who underwent curative resection as the initial treatment at two high-volume medical centres, between January 2005 and September 2019. The least absolute shrinkage and selection operator (LASSO) regression model was utilised to select potentially relevant features. Multivariate Cox proportional hazards analysis was used to develop a novel nomogram. FINDINGS: The nomogram comprised age, fibrinogen levels, prognostic nutritional index (PNI), platelet-lymphocyte ratio (PLR), mitotic counts and tumour size, which provided favourable calibration and discrimination in the training dataset with an AUC of 0•749 and a C-index of 0•742 (95%CI:0•689-0•804). Further, it showed acceptable discrimination in the validation cohort, with an AUC of 0•778 and C-index of 0•735 (95%CI:0•634-0•846). The time-dependant receiver operating characteristic (ROC) curves performed well throughout the observation period. Additionally, the nomogram could classify high-risk GISTs into 'very high-risk' and 'general high-risk' groups with a hazard ratio (HR) of 5•190 (95%CI: 3•202-8•414) and 5•438 (95%CI: 2•236-13•229) for the training and validation datasets, respectively. INTERPRETATION: The nomogram independently predicted post-operative recurrence-free survival (RFS) in high-risk GIST and showed favourable discrimination and calibration values. It may be a useful clinical tool for identifying 'very high-risk' GIST, by allowing treatment strategy optimisation in these patients. FUNDING: National Natural Science Foundation of China (No. 81702386 and 81874184).

12.
Toxicol Appl Pharmacol ; 407: 115252, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32987027

RESUMO

Acute lung injury (ALI) is a severe disease for which effective drugs are still lacking at present. Forsythia suspensa is a traditional Chinese medicine commonly used to relieve respiratory symptoms in China, but its functional mechanisms remain unclear. Therefore, forsythoside A (FA), the active constituent of F. suspensa, was studied in the present study. Inflammation models of type II alveolar epithelial MLE-12 cells and BALB/c mice stimulated by lipopolysaccharide (LPS) were established to explore the effects of FA on ALI and the underlying mechanisms. We found that FA inhibited the production of monocyte chemoattractant protein-1 (MCP-1/CCL2) in LPS-stimulated MLE-12 cells in a dose-dependent manner. Moreover, FA decreased the adhesion and migration of monocytes to MLE-12 cells. Furthermore, miR-124 expression was upregulated after FA treatment. The luciferase report assay showed that miR-124 mimic reduced the activity of CCL2 in MLE-12 cells. However, the inhibitory effects of FA on CCL2 expression and monocyte adhesion and migration to MLE-12 cells were counteracted by treatment with a miR-124 inhibitor. Critically, FA ameliorated LPS-induced pathological damage, decreased the serum levels of tumor necrosis factor-α and interleukin-6, and inhibited CCL2 secretion and macrophage infiltration in lungs in ALI mice. Meanwhile, administration of miR-124 inhibitor attenuated the protective effects of FA. The present study suggests that FA attenuates LPS-induced adhesion and migration of monocytes to type II alveolar epithelial cells though upregulating miR-124, thereby inhibiting the expression of CCL2. These findings indicate that the potential application of FA is promising and that miR-124 mimics could also be used in the treatment of ALI.

13.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3997-4003, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893600

RESUMO

Citri Sarcodactylis Fructus is a both medicinal and edible species specified by the China Ministry of Health, with a long history in China. According to the ancient monographs about materia medica, it was found that the records of the Citri Sarcodactylis Fructus on the original plants were confused. This paper reviewed the ancient monographs about materia medica, and made a summarization and textual research on the name, origin, habitat, processing methods, medicinal properties and clinicacy efficacy of Citri Sarcodactylis Fructus based the comprehensive analysis on modern literatures and authoritative books of Chinese herbal medicine. The results indicated that there were many bynames of Citri Sarcodactylis Fructus. Before the Yuan Dynasty, there was a mixed use of Citri Sarcodactylis Fructus and Citri Fructus, which were not distinguished from each other in terms of nature and taste until the Yuan dynasty. Citri Sarcodactylis Fructus was a varietas of Citri Fructus. The main shape of the original plant of Citri Sarcodactylis Fructus is "like a human hand with fingers" as recorded in ancient monographs about materia medica. The main places of origin of Citri Sarcodactylis Fructus were Guangdong, Zhejiang, Fujian, Sichuan, which were relatively stable. There were fewer records about medicinal proces-sing methods of Citri Sarcodactylis Fructus. Only steaming and baking methods were found in ancient monographs about materia medica, and the steaming method could reduce the irritability of Citri Sarcodactylis Fructus. The processing of therapeutic dietary of Citri Sarcodactylis Fructus was widely used in folk, which was represented by Chaozhou Laoxianghuang, a traditional succade made of Citri Sarcodactylis Fructus. According to the 2015 edition of Chinese Pharmacopoeia, Citri Sarcodactylis Fructus had effects in soothing liver and regulating gas, relieving pain in the stomach, eliminating dampness and resolving phlegm, which was basically consistent with the descriptions in ancient monographs about materia medica. This paper defined the original plant of Citri Sarcodactylis Fructus, and sorted out and summarized the processing methods, nature and taste of Citri Sarcodactylis Fructus, so as to provide data support for the standardization of the processing technology and the development and utilization of Citri Sarcodactylis Fructus.


Assuntos
Medicamentos de Ervas Chinesas , Materia Medica , China , Frutas , Humanos , Medicina Tradicional Chinesa
14.
Biochem Pharmacol ; 182: 114221, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32949583

RESUMO

Diabetic peripheral neuropathy (DPN) is one of the most common microvascular complications occurring in both type 1 and type 2 diabetes mellitus patients. Oxidative stress (OS) plays a key role in the pathogenesis of DPN; thus, antioxidant therapy is considered a promising strategy for treating DPN. Diphenyl diselenide (DPDs) is an organic selenium compound with antioxidant pharmacological activities. This study aimed to evaluate its preventive and therapeutic effects on DPN in rats with streptozotocin (STZ)-induced diabetes and explore the underlying mechanisms. In vitro, RSC96 cells were exposed to high glucose (100 mM) and then treated with different concentrations of DPDs (1, 10, 25 and 50 µM). Notably, DPDs markedly suppressed high glucose-induced cytotoxicity and oxidative stress in Schwann cells by decreasing reactive oxygen species (ROS) and malondialdehyde (MDA) levels. Furthermore, the DPDs treatment effectively activated Nrf2 signaling and inhibited Keap1 expression. An in vivo DPN model was established in Sprague-Dawley (SD) rats injected with STZ (60 mg·kg-1, ip) and orally administered either different doses of DPDs (5 and 15 mg· kg-1· d-1) for 12 weeks or alpha lipoic acid (ALA, 100 mg kg-1·d-1) as a positive control. The administration of DPDs significantly increased the motor nerve conduction velocity (MNCV), improved thermal and mechanical hyperalgesia and the sciatic nerve morphology, and ameliorated oxidative stress in the serum and the sciatic nerve of rats with DPN. Mechanistically, DPDs reduced the level of Keap1 and stimulated Nrf2 signaling in the sciatic nerve. Taken together, the results of this study indicate that DPDs ameliorates experimental DPN as an antioxidant by activating the Nrf2/Keap1 signaling pathway. DPDs may represent a new alternative treatment for DPN.

15.
Mol Biol Rep ; 47(8): 6239-6246, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32803501

RESUMO

Dust mites are an important cause of allergic diseases worldwide. The traces of Dermatophagoides farinae and Dermatophagoides pteronyssinus can be found all over the world, while Blomia tropicalis are more common allergenic mites in tropical areas. A variety of allergenic components in dust mites have been found, apart from the different positive rates of IgE reactions in dust mite allergic patients, their biological characteristics, effects on the innate immune system, and especially their distribution characteristics in patients are different. Studying the relationship between dust mite allergens and clinical significance will help for diagnosis of patients and formulation of corresponding Allergen Specific Immunotherapy.

16.
Molecules ; 25(16)2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32824539

RESUMO

Schizonepetae Spica (SS) is commonly used for treating colds, fevers, bloody stool and metrorrhagia in China. To treat colds and fevers, traditional Chinese medicine doctors often use raw SS, while to treat bloody stool and metrorrhagia, they usually use Schizonepetae Spica Carbonisata (SSC; raw SS processed by stir-frying until carbonization). However, there have been limited investigations designed to uncover the mechanism of stir-fry processing. In the present study, a method combining gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC) was developed for the comprehensive analysis of the chemical profiles of SS and SSC samples. Principal component analysis of the GC-MS data demonstrated that there were 16 significant differences in volatile compounds between the SS and SSC samples. The simultaneous quantification of six nonvolatile compounds was also established based on HPLC, and remarkable differences were found between the two products. These changes were probably responsible for the various pharmacological effects of SS and SSC as well as the observed hepatotoxicity. Finally, the mechanisms could be rationalized by deducing possible reactions involved in the transformation of these marker components. This work reports a new strategy to reveal the chemical transformation of SS during stir-fry processing.

17.
J Agric Food Chem ; 68(35): 9287-9298, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32786824

RESUMO

3-Chlorogentisate is a key intermediate in the catabolism of the herbicide dicamba in R. dicambivorans Ndbn-20. In this study, we identified two gentisate 1,2-dioxygenases (GDOs), DsmD and GtdA, from Ndbn-20. The amino acid sequence similarity between DsmD and GtdA is 51%. Both of them are dimers and showed activities to gentisate and 3-chlorogentisate but not 3,6-dichlorogentisate (3,6-DCGA) or 6-chlorogentisate in vitro. The kcat/Km of DsmD for 3-chlorogentisate was 28.7 times higher than that of GtdA, whereas the kcat/Km of DsmD for gentisate was only one-fourth of that of GtdA. Transcription of dsmD was dramatically induced by 3-chlorogentisate but not gentisate, whereas gtdA was not induced. Disruption of dsmD resulted in a significant decline in the degradation rates of 3-chlorogentisate and dicamba but had no effect on the degradation of gentisate, whereas the result of disruption of gtdA was converse; the disruption of both dsmD and gtdA led to the inability to degrade 3-chlorogentisate and gentisate. This study revealed that 3-chlorogentisate but not gentisate or 3,6-DCGA is the ring-cleavage substrate in the dicamba degradation pathway in R. dicambivorans Ndbn-20; DsmD is specifically responsible for cleavage of 3-chlorogentisate, whereas GtdA is a general GDO involved in the catabolism of various natural aromatic compounds.

18.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(4): 557-565, 2020 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-32840070

RESUMO

Coronavirus disease 2019 (COVID-19) has spread rapidly around the world. In order to diagnose COVID-19 more quickly, in this paper, a depthwise separable DenseNet was proposed. The paper constructed a deep learning model with 2 905 chest X-ray images as experimental dataset. In order to enhance the contrast, the contrast limited adaptive histogram equalization (CLAHE) algorithm was used to preprocess the X-ray image before network training, then the images were put into the training network and the parameters of the network were adjusted to the optimal. Meanwhile, Leaky ReLU was selected as the activation function. VGG16, ResNet18, ResNet34, DenseNet121 and SDenseNet models were used to compare with the model proposed in this paper. Compared with ResNet34, the proposed classification model of pneumonia had improved 2.0%, 2.3% and 1.5% in accuracy, sensitivity and specificity respectively. Compared with the SDenseNet network without depthwise separable convolution, number of parameters of the proposed model was reduced by 43.9%, but the classification effect did not decrease. It can be found that the proposed DWSDenseNet has a good classification effect on the COVID-19 chest X-ray images dataset. Under the condition of ensuring the accuracy as much as possible, the depthwise separable convolution can effectively reduce number of parameters of the model.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Infecções por Coronavirus/diagnóstico por imagem , Aprendizado Profundo , Humanos , Pneumonia Viral/diagnóstico por imagem , Raios X
19.
J Environ Manage ; 274: 111178, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32771774

RESUMO

Papermaking waste liquid (black liquor) is a serious source of water pollution worldwide. The subsequent treatment of it is very difficult cause it contains a large amount of lignin, inorganic salts, organic matter, and pigments, which lead to serious water pollution. Lignin is the main by-product of the paper industry and is the only natural aromatic recyclable resource. Its effective utilization rate is currently less than 3%. Therefore, how to effectively recycle lignin in papermaking waste liquid and further synthesize industrialized products is of great significance to the sustainable development and environmental protection. Besides, based on the shortage of petroleum resources in recent years, the application of biomass resources instead of petroleum resources in the industry is also an important issue. In this article, we explored the best optimal conditions for the oxypropylation and esterification of lignin, and prepared bio-bitumen based on modified lignin, and then applied it to the waterproof coating sheets. FTIR and mechanical properties (softening point, low-temperature flexibility, peel strength, etc.) were tested on the obtained waterproof coating sheets. The results show that the addition of modified lignin reduced the softening point and peel strength of the coating sheets. Interestingly, both oxypropylated lignin (OL) and esterified lignin (OEL) were very beneficial to resist the decrease in peel strength during the aging process, showing a significant improvement in the performance of the coating sheets after aging compared to the control.


Assuntos
Hidrocarbonetos , Lignina , Biomassa
20.
Oncogene ; 39(39): 6231-6244, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32826951

RESUMO

Hypoxic tumor microenvironment(TME) is a universal feature in solid carcinoma and is associated with unfavorable prognosis. Tumor-derived exosomes are now significantly implicating in mediating cellular communication and interactions in TME. The aim of this study was to identify exosomal miR-301a-3p involved in gastric cancer(GC) progression and metastasis. Here, we found hypoxia promote GC exosomes release and miR-301a-3p expression in an HIF-1α-dependent manner. In hypoxic TME, enriched miR-301a-3p could be transmitted between GC cells via exosomes and then contributed to inhibit HIF-1α degradation through targeting PHD3, that were capable to hydroxylate HIF-1α subunits to ubiquitinate degradation. This synergistical positive feedback loop between HIF-1α and miR-301a-3p facilitated GC proliferation, invasion, migration, and epithelial-mesenchymal transition. In clinical samples, we further discovered circulating exosomal miR-301a-3p in serum was positively related with peritoneal metastasis. Collectively, these data indicate that GC cells could generate miR-301a-3p-rich exosomes in the hypoxic TME, which then help to HIF-1α accumulation and promote GC malignant behaviors and metastasis. Exosomal miR-301a-3p/HIF-1α signaling axis may serve as a promising predictor and potential therapeutic target of GC with metastasis.

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