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Under the background of urgent need for computer-aided technology to provide physicians with objective decision support, aiming at reducing the false positive rate of nodule CT detection in pulmonary nodules detection and improving the accuracy of lung nodule recognition, this paper puts forward a method based on ensemble learning to distinguish between malignant and benign pulmonary nodules. Firstly, trained on a public data set, a multi-layer feature fusion YOLOv3 network is used to detect lung nodules. Secondly, a CNN was trained to differentiate benign from malignant pulmonary nodules. Then, based on the idea of ensemble learning, the confidence probability of the above two models and the label of the training set are taken as data features to build a Logistic regression model. Finally, two test sets (public data set and private data set) were tested, and the confidence probability output by the two models was fused into the established logistic regression model to determine benign and malignant pulmonary nodules. The YOLOv3 network was trained to detect chest CT images of the test set. The number of pulmonary nodules detected in the public and private test sets was 356 and 314, respectively. The accuracy, sensitivity and specificity of the two test sets were 80.97%, 81.63%, 78.75% and 79.69%, 86.59%, 72.16%, respectively. With CNN training pulmonary nodules benign and malignant discriminant model analysis of two kinds of test set, the result of accuracy, sensitivity and specificity were 90.12%, 90.66%, 89.47% and 88.57%, 85.62%, 90.87%, respectively. Fused model based on YOLOv3 network and CNN is tested on two test sets, and the result of accuracy, sensitivity and specificity were 93.82%, 94.85%, 92.59% and 92.31%, 92.68%, 91.89%, respectively. The ensemble learning model is more effective than YOLOv3 network and CNN in removing false positives, and the accuracy of the ensemble. Learning model is higher than the other two networks in identifying pulmonary nodules.

Tricarboxylic acid cycle is an important pathway and the metabolites of tricarboxylic acid cycle, simple organic acids, play important roles in many physiological processes. The new conditions of high performance liquid chromatography (HPLC) with improved separation selectivity were developed and optimized by choosing suitable store solvent, methanol, which can catalyze the reaction, aldol condensation, and facilitate the formation of new compound to improve simultaneous detection of nine metabolites of tricarboxylic acid cycle, including lactic acid, pyruvic acid, citric acid, alpha-ketoglutaric acid, malic acid, succinic acid, cis-aconitic acid, itaconic acid, and fumaric acid, and be applied in analysis of the nine metabolites in psoriasis mice skin. This study shows that in process of developing methods, expect conventional chromatographic condition, solvent should also be considered carefully.

Prostate cancer (PC) is the second leading cause of cancer-related death among men worldwide. Downregulation of miR-485-3p has been revealed to participate in the tumorigenesis and progression of many types of cancer. However, the clinical and biological role of miR-485-3p in PC remains largely unknown.The expression of miR-485-3p was analyzed in the published databases and detected in our clinical samples and cell lines by RT-qPCR assay. CCK8, transwell invasion and migration, and colony formation assays were performed to investigate the biological function of miR-485-3p. Bioinformatical analysis, RIP, western blotting and luciferase reporter assays were carried out to explore the downstream mechanism of miR-485-3p.The level of miR-485-3p was downregulated in PC tissues, particularly in primary PC tissues with metastasis relative to normal prostate tissues. miR-485-3p downregulation was positively correlated with poor disease-free and overall survival in patients with PC. Functionally, miR-485-3p overexpression dramatically suppressed the proliferation, migration and invasion ability of PC cells in vitro. Mechanistically, miR-485-3p overexpression suppressed the activity of TGF-β signaling by targeting TGFBR2 to play tumor-suppressive roles in PC progression.Our study reports the miR-485-3p/TGFBR2/ TGF-β signaling axis in tumor development of PC, suggesting miR-485-3p may be a potential target to develop therapeutic strategies against PC.

Recalcitrant dissolved organic carbon (RDOC) resulting from microbial carbon (MCPs) holds promise as a relatively long-term natural carbon sink in marine environments. However, the RDOC formation mechanism remains uncertain in terrestrial aquatic systems. To determine the microbial impacts on autochthonous dissolved organic carbon (DOC), RDOC formation, and the critical influencing bacteria species, spatial changes in hydrochemistry, carbon isotopes, and microbial diversity were investigated in water samples from the karstic Lijiang River, southwest China. Samples were collected at various locations along the river system in May and July 2017. The biodegradable DOC (BDOC), RDOC, soil sourced DOC (SDOC), submerged aquatic vascular plant sourced DOC (PDOC) and microbial sourced DOC (MDOC) were calculated using the in-situ microbial incubation method, stable carbon isotopes and C/N ratio. RDOC accounted for 67% to 93% of DOC concentrations, measuring 1.3 mg/L and 1.2 mg/L in May and July, respectively. In May, BDOC concentrations increased by 0.05 mg/L from 0.18 mg/L to 0.23 mg/L, but decreased by 0.43 mg/L from 0.66 mg/L to 0.23 mg/L in July. The spatiotemporal variation of BDOC indicated photosynthesis was the main BDOC source and induced high autochthonous DOC formation, especially in May. However, RDOC was the dominant accumulation component in Lijiang River. MDOC increased by 0.86 mg/L from 0 to 0.86 mg/L in May and 0.78 mg/L from 0.10 mg/L to 0.88 mg/L in July, which was the dominant accumulated DOC and RDOC component. The abundance of Sporichthyaceae accounted for 3.4%-22.6% in May and Novosphingobium accounted for 3.5%-34.0% in July. These were the critical bacteria species induced MDOC formation, which were confirmed by their abundances in KEGG pathway modules determined by PICRUAST2. These results demonstrate that heterotrophic bacteria dominate autochthonous DOC and RDOC formation in the karst surface river, which is valuable for understanding organic carbon cycling in karstic aquatic systems.

Optogenetic method is widely used for dissecting the neuronal function and connectivity in a specific neural circuit, which can help understanding how the animal process information and generate behavior. The nematode C. elegans has a simple but complete nervous system, making it an attractive model to study the dynamics signals of neural circuits. However, in vivo analysis on neural circuits usually rely on the complex and expensive optical equipment to allow optogenetic stimulating the neuron while recording its activities in such a freely moving animal. Hence, in this paper we reported a portable optofluidic platform that works based on optical fiber illumination and functional imaging for worm optogenetic manipulation. A light beam from LED laser pen crossing the 3D-printed optical fiber channel is used to activate the neurons specific-expressed with light sensitive proteins ChR-2. The imaging light path is perpendicular to the stimulation light, which allows activating neuron precisely and measuring cellular signals simultaneously. By using such an easy-to-assemble device, optical stimulation of the specific neurons and detection of dynamic calcium responses of other neurons could be proceeded simultaneously. Thus, the developed microfluidic platform puts forward a simple, rapid and low-cost strategy for further neural circuits studies.

Prostate cancer (PCa) is one of the most common cancers in males and particularly tends to metastasize to bone. Currently, metastatic bone disease is incurable, and new therapies need to be developed. Our study aims to determine the role of miR-127-3p in PCa metastasis to bone. The results demonstrate that miR-127-3p is markedly reduced in bone metastasis-positive PCa tissues relative to that in bone metastasis-negative PCa tissues. Furthermore, overexpressing miR-127-3p inhibits PCa cell invasion and migration in vitro by targeting the proteasome β-subunit PSMB5. Moreover, CCCTC-binding factor (CTCF) transcriptionally inhibits miR-127-3p by interacting with the miR-127-3p promoter. Collectively, this study uncovers a novel mechanism of the CTCF/miR-127-3p/PSMB5 axis in promoting PCa bone metastasis, indicating that miR-127-3p could function as a promising therapeutic target against bone metastasis.

Aquatic photosynthesis transforms inorganic carbon to organic carbon (OC), which contributes to autochthonous organic carbon (AOC) in sediment and particulate organic carbon in surface karst aquatic systems. Aquatic plant and microbes are participated in autochthonous dissolved organic carbon (ADOC) formation in surface karst aquatic systems, but the composition and formation of ADOC remains little known, which leaves problem on calculation of organic carbon flux. In this study, the Lijiang River was chosen as typical surface karst river to identify the DOC composition and its origin, and to explore the environmental influencing factors. Samples were collected seasonally from the upper to lower reaches of the river to analyze hydrochemical parameters and the excitation-emission matrix (EEM) spectrum of chromophoric dissolved organic matter (CDOM). Three CDOM components were calculated by parallel factor analysis (PARAFAC) from EEM spectra, which were allochthonous soil-sourced DOC (SDOC), autochthonous aquatic plant-sourced DOC (APDOC), and microbial-sourced DOC (MDOC). Based on the DOC component concentrations, SDOC is induced by large amounts of precipitation causing soil erosion in summer. APDOC formation is encouraged by moderate water temperatures in spring and fall restricted by high water turbidity in summer. The significant positive linear correlations between APDOC and dissolved inorganic carbon (DIC) and MDOC indicate DIC fertilization effect in karst aquatic systems directly promotes APDOC formation and indirectly promotes MDOC. Our study develops a relatively simple way to calculate composition of karst aquatic DOC, which demonstrates the participation of aquatic plants and microbes in APDOC production and reiterate that autochthonous DOC should be considered when calculating the carbon sink in surface karst aquatic systems.

Psoriasis is a common chronic inflammatory skin disease which may exhibit a variety of skin clinical manifestations associated with multiple comorbidities. However, its pathogenesis associated with metabolism has not yet been understood. The metabolites of tricarboxylic acid (TCA) cycle and amino acids are interlinked with each other and involve many physiological processes. This study determined 32 metabolites of TCA cycle and amino acids in psoriasis using an improved GC-MS method. This one-pot derivatization applied silanization and oximation simultaneously for easy, quick and sensitive quantitative detection of 32 metabolites in serum of patients with psoriasis. Through the established GC-MS method, 32 metabolites in serum were detected in a single run. The result of this preliminary study showed that there were significant alterations of the metabolites in tricarboxylic acid (TCA) cycle and amino acids before and after treatment. A shift towards healthy controls of these metabolites after treatment was observed using principal component analysis (PCA) as well. Receiver operating-characteristic curve (ROC) analysis of the analyzed 32 metabolites filtered 5 potential biomarkers of the clinical efficacy of the treatment. This result suggested the importance of these metabolites in the pathogenesis of psoriasis. To our best know, this is the first targeted metabolomics work to study the changes of TCA cycle metabolites and amino acids in the background of treatment of psoriasis.