Intestinal-type gastric carcinoma exhibits a multistep carcinogenic sequence from adenoma to carcinoma with a gradual increase in genomic alterations. But the roles of microRNAs (miRNA) in this ...multistage cascade are not fully explored. To identify differentially expressed miRNA (DEM) during early gastric carcinogenesis, we performed miRNA microarray profiling with 24 gastric cancers and precursor lesions (7 early gastric cancer EGC, 3 adenomas with high-grade dysplasia, 4 adenomas with low-grade dysplasia, and 10 adjacent normal tissues). Alterations in the expression of 132 miRNA were detected; these were categorized into three groups based on their expression patterns. Of these, 42 miRNAs were aberrantly expressed in EGC. Five miRNA (miR-26a, miR-375, miR-574-3p, miR-145, and miR-15b) showed decreased expression since adenoma. Expression of two miRNA, miR-200C and miR-29a, was down-regulated in EGCs compared to normal mucosa or adenomas. Six miRNA (miR-601, miR-107, miR-18a, miR-370, miR-300, and miR-96) showed increased expression in gastric cancer compared to normal or adenoma samples. Five representative miRNAs were further validated with RT-qPCR in independent 77 samples. Taken together, these results suggest that the dysregulated miRNA show alterations at the early stages of gastric tumorigenesis and may be used as a candidate biomarker.
Fiber bending during carbon fiber reinforced plastic (CFRP) milling is an important factor on the machined surface quality. During milling, the fiber first contacts the rake face instead of the tool ...edge at a certain cutting angle, and then the fiber is bent instead of being cut by the tool, causing the matrix and the fiber to fall out. The fiber is then broken from inside the machined surface and subsequently pulled out as the tool rotates, which are known as pull-out fibers. The machining defect is the main cause of deteriorating the surface quality. To reduce such machining defects, it is important to predict the fiber bending during CFRP milling. However, it is difficult to determine where fiber bending occurs because the fiber cutting angle changes every moment as the tool rotates. This study analyzed the fiber cutting mechanism considering bent fibers during CFRP milling and proposed a method to identify the type of machining mechanism through machining sound analysis. Moreover, CFRP milling simulation was performed to numerically analyze the machining parameters such as fiber cutting angle, fiber length, and the magnitude of fiber bending at different milling conditions. Through experiments, it was verified that fiber bending or defects can be identified through sound analysis of machining in the high-frequency range between 7500 and 14,800 Hz. The effect of chip thickness in up-milling and down-milling on fiber bending was investigated by analyzing simulation and sound signal, and their effects on cutting force and machining quality was experimentally verified.
In this paper, a new topology is proposed that can significantly reduce the converter rated power and increase the efficiency of total photovoltaic (PV) system. Since the output voltage of PV module ...has very wide operating range, in general, the DC/DC converter is used to produce constant high-DC-link voltage for DC/AC inverter. According to the analysis of the proposed topology, only 20% of total PV system power is processed by the DC/DC power conversion stage. The DC/DC power conversion stage used in proposed topology has flat efficiency curve throughout all load range and very high efficiency characteristics. In the proposed topology, because the converter efficiency curve is almost flat throughout all load range, the total system efficiency at light load is dramatically improved. The proposed topology is implemented for 250-kW power conditioning system . This system has only three DC/DC power conversion stage with 24-kW rated power. It is only one-third of total system power. The experimental results show that the proposed topology has good performance.
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•Novel N-doped biochar was prepared via hydrothermal route-enabled carbonization.•−OH groups in NHC assisted in generating −CN.•The optimal catalyst exhibited an excellent performance ...for PMS activation.•Graphitic-N, oxygenated functional groups, and pyridinic-N were the active sites.•A nonradical mechanism dominated in the degradation of the organics present in water.
Nitrogen-doped biochar (HTNBC) was prepared from sewage sludge via hydrothermal route-enabled carbonization, and the optimized HTNBC was found to efficiently activate peroxymonosulfate (PMS) by aiming the less consumption of the chemicals. The optimal HTNBC degraded a 0.1 mM aqueous solution of bisphenol A (BPA) within 10 min at a rate of 0.62 min−1, exhibiting a significantly superior catalytic activity compared to that of pristine sludge biochar. The HTNBC/PMS system effectively oxidized various organic pollutants, including BPA, sulfamethoxazole, 4-chlorophenol, carbamazepine, and nitrobenzene with a low consumption of PMS (1.0 mM) and a low catalyst loading (0.2 g/L). The active sites for PMS activation were identified as graphitic-N, pyridinic-N, and carbonyl groups, besides structural defects and a high specific surface area were also important. The primary oxidation mechanism was anticipated to involve non-radical pathways followed by radical-induced oxidation, in which the surface-bound reactions dominate. The HTNBC/PMS system acts over a wide pH range and exhibits a high resistance to the inorganic anions of natural water. Our results indicate that nitrogen doping via a hydrothermal route allows the fabrication of biochar with a greater abundance of oxygen functional groups, and the specific nitrogen species present within the carbon matrix are also of importance in the development of advanced carbon catalysts.
Endoscopic submucosal dissection (ESD) has been widely accepted for treating superficial esophageal squamous cell carcinoma (SESCC). However, long-term outcomes of ESD and esophagectomy for SESCC ...have not been compared. We compared the clinical outcomes of ESD and esophagectomy in a matched cohort.
Patients who underwent ESD and esophagectomy for SESCC were included. We selected SESCCs without obvious submucosal invasion from the surgical database by reviewing endoscopic images. To minimize the effect of selection bias, propensity score matching was performed. Overall survival (OS), disease-specific survival (DSS), recurrence-free survival (RFS), and metachronous RFS were compared between the 2 groups. Adverse event rates were also compared.
In a matched cohort of 120 pairs, OS, DSS, and RFS were comparable between the 2 groups. The 5-year OS, DSS, and RFS rates were 93.9% versus 91.2%, 100% versus 97.4%, and 92.8% versus 95.3% for the ESD and esophagectomy groups, respectively. The metachronous RFS was worse in the ESD group than in the esophagectomy group (P = .004). The 5-year metachronous RFS rates were 90.3% versus 100% for the ESD and esophagectomy groups, respectively. The esophagectomy group showed a higher overall adverse event rate than the ESD group (55.5% vs 18.5%, P < .0001). In each subgroup of mucosal and submucosal cancer, OS, DSS, and RFS were also comparable between the 2 groups.
ESD provides long-term outcomes comparable with esophagectomy in patients with SESCC without endoscopic evidence of obvious submucosal invasion. ESD should be considered as the first-line treatment for these patients.
Chemotherapy is ubiquitous in first-line treatment of advanced gastric cancer, yet responses are heterogeneous, and little is known about mediators of chemotherapy response. To move forward, an ...understanding of the effects of standard chemotherapy on the tumor-immune microenvironment (TME) is needed. Coupling whole-exome sequencing, bulk RNA and single-cell transcriptomics from paired pretreatment and on-treatment samples in treatment-naïve patients with HER2-positive and HER2-negative gastric cancer, we define features associated with response to platinum-based chemotherapy. Response was associated with on-treatment TME remodeling including natural killer (NK) cell recruitment, decreased tumor-associated macrophages, M1-macrophage repolarization, and increased effector T-cell infiltration. Among chemotherapy nonresponders, we observed low/absent PD-L1 expression or modulation, on-treatment increases in Wnt signaling, B-cell infiltration, and LAG3-expressing T cells coupled to an exodus of dendritic cells. We did not observe significant genomic changes in early on-treatment sampling. We provide a map of on-treatment TME modulation with standard chemotherapy and nominate candidate future approaches.
Using paired pretreatment and on-treatment samples during standard first-line chemotherapy, we identify chemotherapy-induced NK-cell infiltration, macrophage repolarization, and increased antigen presentation among responders. Increased LAG3 expression and decreased dendritic cell abundance were seen in nonresponders, emphasizing remodeling of the TME during chemotherapy response and resistance. This article is highlighted in the In This Issue feature, p. 873.
An outbreak of highly pathogenic avian influenza, caused by a novel reassortant influenza A (H5N8) virus, occurred among poultry and wild birds in South Korea in 2014. The aim of this study was to ...evaluate the pathogenesis in and mode of transmission of this virus among domestic and wild ducks. Three of the viruses had similar pathogenicity among infected domestic ducks: the H5N8 viruses were moderately pathogenic (0%-20% mortality rate); in wild mallard ducks, the H5N8 and H5N1 viruses did not cause severe illness or death; viral replication and shedding were greater in H5N8-infected mallards than in H5N1-infected mallards. Identification of H5N8 viruses in birds exposed to infected domestic ducks and mallards indicated that the viruses could spread by contact. We propose active surveillance to support prevention of the spread of this virus among wild birds and poultry, especially domestic ducks.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background Frozen shoulder is a debilitating condition characterized by gradual loss of glenohumeral motion with chronic inflammation and capsular fibrosis. Yet its pathogenesis remains largely ...unknown. We hypothesized that the subacromial bursa may be responsible for the pathogenesis of frozen shoulder by producing inflammatory cytokines. Materials and methods We obtained joint capsules and subacromial bursae from 14 patients with idiopathic frozen shoulder and from 7 control subjects to determine the expression levels of interleukin (IL) 1α, IL-1β, IL-6, tumor necrosis factor α (TNF-α), cyclooxygenase (COX) 1, and COX-2 by real-time reverse transcriptase–polymerase chain reaction, immunohistochemistry, and enzyme-linked immunosorbent assay. Results IL-1α, IL-1β, TNF-α, COX-1, and COX-2 were expressed at significantly high levels in the joint capsules of the frozen shoulder group compared with those of the control group. Intriguingly, IL-1α, TNF-α, and COX-2 were also expressed at significantly high levels in the subacromial bursae of the frozen shoulder group compared with those of the control group. Immunohistochemical analysis showed increased expression of COX-2 in both the joint capsules and subacromial bursae of the frozen shoulder group. Conclusions These findings imply that elevated levels of inflammatory cytokines in the subacromial bursa may be associated with the pathogenesis of inflammation evolving into fibrosis.
•Matrix shear behavior is found to affect milled CFRP surface quality.•Shear strain energy of the whole matrix deformed by a milling tool was calculated.•The geometrical relationship between fibers ...and a cutter was used in the model.•Ra and Rz of the machined surface were proportional to the calculated energy.
Fiber bending by the cutting tool is one of the dominant causes of fiber pull-out on machined surfaces during CFRP milling. During the bending, the polymer matrix between the fibers is subjected to shear stress resulting in fiber-matrix debonding. The increase in the debonding length causes an increase in the fiber pull-out length. In milling, not all the new surfaces created by tool-workpiece engagement become the machined surface. However, during this process, the strain energy absorbed by the deformed matrix is released into fiber-matrix debonding along the fibers which can cause fiber pull-out on the machined surface. In this study, shear strain energy of polymer matrix due to fiber bending during milling tool-workpiece engagement was calculated with the geometrical relationship between fibers and a cutting edge. We found that the increase in Ra and Rz of the machined surface had clear tendencies to the increase in the calculated energy.
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