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Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disorder that affects nearly 1 in 3000 infants. Neurofibromin inactivation and NF1 gene mutations are involved in various aspects of neuronal function regulation, including neuronal development induction, electrophysiological activity elevation, growth factor expression, and neurotransmitter release. NF1 patients often exhibit a predisposition to tumor development, especially in the nervous system, resulting in the frequent occurrence of peripheral nerve sheath tumors and gliomas. Recent evidence suggests that nerves play a role in the development of multiple tumor types, prompting researchers to investigate the nerve as a vital component in and regulator of the initiation and progression of NF1-related nervous system tumors.In this review, we summarize existing evidence about the specific effects of NF1 mutation on neurons and emerging research on the role of nerves in neurological tumor development, promising a new set of selective and targeted therapies for NF1-related tumors.

Purpose To identify and quantify lung changes associated with coronavirus disease-2019 (COVID-19) with quantitative lung CT during the disease. Methods This retrospective study reviewed COVID-19 patients who underwent multiple chest CT scans during their disease course. Quantitative lung CT was used to determine the nature and volume of lung involvement. A semi-quantitative scoring system was also used to evaluate lung lesions. Results This study included eighteen cases (4 cases in mild type, 10 cases in moderate type, 4 cases in severe type, and without critical type cases) with confirmed COVID-19. Patients had a mean hospitalized period of 24.1 ± 7.1 days (range: 14–38 days) and underwent an average CT scans of 3.9 ± 1.6 (range: 2–8). The total volumes of lung abnormalities reached a peak of 8.8 ± 4.1 days (range: 2–14 days). The ground-glass opacity (GGO) volume percentage was higher than the consolidative opacity (CO) volume percentage on the first CT examination (Z = 2.229, P = 0.026), and there was no significant difference between the GGO volume percentage and that of CO at the peak stage (Z = - 0.628, P = 0.53). The volume percentage of lung involvement identified by AI demonstrated a strong correlation with the total CT scores at each stage (r = 0.873, P = 0.0001). Conclusions Quantitative lung CT can automatically identify the nature of lung involvement and quantify the dynamic changes of lung lesions on CT during COVID-19. For patients who recovered from COVID-19, GGO was the predominant imaging feature on the initial CT scan, while GGO and CO were the main appearances at peak stage. Electronic supplementary material The online version of this article (10.1007/s10140-020-01856-4) contains supplementary material, which is available to authorized users.

Background: Neurofibromatosis type 1 (NF1), a genetic tumor predisposition syndrome that affects about 1 in 3000 newborns, is caused by mutations in the NF1 gene and subsequent inactivation of its encoded neurofibromin. Neurofibromin is a tumor suppressor protein involved in the downregulation of Ras signaling. Despite a diverse clinical spectrum, one of several hallmarks of NF1 is a peripheral nerve sheath tumor (PNST), which comprises mixed nervous and fibrous components. The distinct spatiotemporal characteristics of plexiform and cutaneous neurofibromas have prompted hypotheses about the origin and developmental features of these tumors, involving various cellular transition processes. Methods: We retrieved published literature from PubMed, EMBASE, and Web of Science up to 21 June 2022 and searched references cited in the selected studies to identify other relevant papers. Original articles reporting the pathogenesis of PNSTs during development were included in this review. We highlighted the Schwann cell (SC) lineage shift to better present the evolution of its corresponding cellular origin hypothesis and its important effects on the progression and malignant transformation of neurofibromas. Conclusions: In this review, we summarized the vast array of evidence obtained on the full range of neurofibroma development based on cellular and molecular pathogenesis. By integrating findings relating to tumor formation, growth, and malignancy, we hope to reveal the role of SC lineage shift as well as the combined impact of additional determinants in the natural history of PNSTs.

Titanium alloy Ti–Al–Nb–Zr has high specific strength and becomes a promising structural material used in the deep sea. The excellent corrosion resistance of the alloy is derived from the protective passive film formed on its surface. By now, full agreement on interpretation of the anti-corrosion performance of the film in marine environment, especially in the deep sea, has not been reached. In this work, the electrochemical performance of two-surface-state Ti–Al–Nb–Zr alloys which are treated by mechanical polishing and anodizing pre-passivation in the simulated shallow sea, 1000 m and 3000 m deep sea environments, is investigated. By interpreting the electrochemical kinetic parameters, it is found that the dominant cathodic process becomes hydrogen evolution in simulated deep sea environments, but the reduction rate is restrained by high hydrostatic pressure, which arrests the passivation of the alloy. Assisted by X-ray photoelectron spectroscopy analysis, it is found that the passive film mainly consists of titanium oxides. There are intermediate oxides with non-stoichiometric ratio involved in the film formation due to the low dissolved oxygen concentration and low temperature. The results of Mott–Schottky and electrochemical impedance show that the film has n-type semiconducting property with oxygen vacancies as the main point defects. The anti-corrosion performance in simulated deep sea environments is one order of magnitude lower than that in the simulated shallow sea environment. However, from 1000 to 3000 m, the corrosion resistance is reduced very slightly. In the inner layers of the passive film and the passive film formed in simulated deep sea environments, the proportion of low-valence titanium oxides is relatively high. The doping of low-valence titanium (Ti(II) or Ti(III)) results in a porous structure and ion permeability of the passive film, as well as relatively low corrosion resistance.

MAPK/extracellular signal-regulated kinase kinase (MEK) 1/2 inhibitors (MEKis) have recently achieved surprising success in treating unresectable plexiform neurofibromas (PNFs). However, few studies have investigated the mechanisms of MEKi resistance in patients with PNF. We determined the efficacy of six different MEKis for treating PNFs, explored drug resistance mechanisms, and identified potential combination therapies to overcome resistance. By screening drug efficacy among six MEKis in human NF1-deficient PNF cell lines, TAK-733 was found to reduce PNF cell viability the most. We then cultured the TAK-733‒resistant cells and explored the potential targets for further treatment. Both high-throughput drug screening and RNA sequencing analyses of MEKi-resistant PNF cells identified cyclin-dependent kinase inhibitors as potential agents for PNFs. Dinaciclib, a cyclin-dependent kinase inhibitor, showed synergistic effects on MEKi-resistant cells. Coadministration of dinaciclib and TAK-733 significantly reduced cell viability and inhibited sphere formation and colony formation. Dinaciclib did not affect MEK signaling but decreased the expression of several prosurvival proteins, including survivin and cyclin-dependent kinase 1, to induce apoptosis and inhibit mitosis. TAK-733/dinaciclib combination therapy induced tumor reduction in PNF patient‒derived xenografts mouse models. Therefore, the combination of MEKi and cyclin-dependent kinase inhibitor may be promising for treating inoperable PNFs, especially when drug resistance exists. Our findings provide evidence for future clinical trials with MEKi-resistant patients with PNF.

Malignant peripheral nerve sheath tumors (MPNST) are aggressive sarcomas with over half of cases developed in the context of neurofibromatosis type 1. Surgical resection is the only effective therapy for MPNST. The prognosis is very dismal once recurrence or metastasis occurs. Epithelial-mesenchymal transition (EMT) is a key process of recurrence and metastasis involving reorganizations of the actin cytoskeleton and actin-binding proteins (ABP) play a non-negligible role. Protein tyrosine phosphatase receptor S (PTPRS), a tumor suppressor previously reported in colorectal cancer, hepatocellular carcinoma and head and neck cancer, is thought to mediate cell migration and invasion by downregulation of EMT. However, its role in MPNST remains unknown. In the present study, by using tissue microarray we demonstrated low expression of PTPRS was related to poor prognosis in MPNST. Knockdown of PTPRS in MPNST cell lines increased migration/invasion and EMT processes were induced with increased N-cadherin and decreased E-cadherin, which indicated PTPRS may serve as a tumor suppressor in MPNST. In addition, we tested all EMT related ABP and found profilin 1 was significantly elevated in PTPRS downregulated MPNST cell lines. As a member of actin-binding proteins, profilins are regulators of actin polymerization and contribute to cell motility and invasion, which have been reported to be responsible for EMT. Moreover, results showed that downregulation of profilin 1 could restore the EMT processes caused by PTPRS downregulation in vitro and in vivo. Furthermore, high expression of profilin 1 was significantly associated with dismal prognosis. These results highlighted PTPRS served as a potential tumor suppressor in the recurrence and metastasis of MPNST via profilin 1 induced EMT processes and it might provide potential targets for future clinical therapeutics.

This work aimed to evaluate the effect of different surface treatments on the shear bond strength of resin nano ceramic to resin cement, thereby providing a theoretical basis for the improvement of clinical application.A total of 150 specimens (10 mm×10 mm×3 mm) were milled from resin nano ceramic blocks (Lava Ultimate) using computer-aided design/computer aided manufacturing(CAD/CAM) technology. The specimens were randomly divided into five groups according to the surface treatment performed, as follows: control, sandblasted, sandblasted+silane, hydrofluoric acid, and hydrofluoric acid+silane groups. After the corresponding surface treatment, the specimens were cemented using Single Bond Universal Adhesive and RelyXTM Ultimate ClickerTM adhesive resin cement. All cemented specimens were placed in distilled water for 24 h and 30 days and subjected to a shear bond strength test in a universal testing machine.The surface treatment and water storage periods showed significant effects on bond strength. Surface treatment with sandblasted+silane showed the highest shear strength values among all tested groups, and the difference was statistically significant (P0.05). A difference was observed between the control and hydrofluoric acid groups, and both had significantly difference compared with other groups (P0.05). Sandblasted and hydrofluoric acid+silane groups were not statistically different, and both had significantly difference compared with other groups (P0.05).The surface of resin nanoceramic treated by sand-blasted, sandblasted+silane, and hydrofluoric acid+silane can improve the bond strength. The sandblasted+silane group had the best the shear bond strength among the groups.目的 评估不同表面处理对纳米复合陶瓷与树脂水门汀剪切粘接强度的影响。方法 将纳米复合陶瓷用计算机辅助设计/计算机辅助制作（CAD/CAM）技术切割成大小为10 mm×10 mm×3 mm的试件150块，并根据表面处理方法不同将试件按随机数字表的方法随机分为5组（n=30）：对照组、喷砂组、喷砂+硅烷组、酸蚀组和酸蚀+硅烷组。各组试件经过相应表面处理后，使用Single Bond Universal通用粘接剂+RelyXTM Ultimate ClikerTM树脂水门汀将树脂试件粘接于纳米复合陶瓷试件上，37 ℃蒸馏水中水浴24 h和30 d，万能试验机进行剪切粘接强度测试。结果 不同表面处理方法、不同的水浴时间都会影响到剪切粘接强度。喷砂+硅烷组的剪切粘接强度最大，与其他各组间差异均具有统计学意义（P0.05）；对照组和酸蚀组间差异无统计学意义，但两组与其他组间差异具有统计学意义（P0.05）；喷砂组和酸蚀+硅烷组之间差异无统计学意义（P0.05），但两组与其他组间差异具有统计学意义（P0.05）。结论 喷砂、喷砂+硅烷、酸蚀+硅烷对纳米复合陶瓷表面处理，均可提高其与树脂水门汀的剪切粘接强度，喷砂+硅烷处理后剪切粘接强度最佳。.

Hydrogen plays a detrimental effect on the degeneration of titanium and its alloys, and it is very important to quantify the hydrogen concentration when estimating the microstructure evaluation of titanium and its alloys in a hydrogen environment. In this paper, the hydrogen atoms are assumed to reside in interstitial sites and in trapping sites such as dislocations, and a mechanic-diffusion coupled model was proposed to describe the stress effects on the diffusion of hydrogen in titanium. A titanium plate with a central crack was modeled to verify the mechanic-diffusion model, and it is solved by the finite element method in commercial software COMSOL. The results indicate that hydrogen diffusion near the crack is determined by the stress state. When the stress state of the crack tip is elastic, the hydrogen will diffuse from both sides of the crack towards the tip and lead to the highest hydrogen concentration in the crack tip. When a plastic zone exists in front of the crack tip, the highest hydrogen concentration at crack surface deviates to the side near the crack tip; a hydrogen concentration peak exists at a characterized distance in front of crack tip initially and then diminishes with the diffusion process. The proposed model is expected to solve the hydrogen concentration under stress in more complex structures.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a highly contagious respiratory virus causing severe morbidity in pigs worldwide. Control strategies for PRRSV often rely on detecting PRRSV, culling or isolating sick pigs, disinfecting pig barns, vaccination, and monitoring for virus spread. Given the high economic impact of PRRSV on pig farms, there is a great need for rapid and reliable PRRSV detection assays. We compared the performance of 2 commercial reverse-transcription real-time PCR (RT-rtPCR) assays, the VetMAX PRRSV NA and EU reagents (ABI assay) and the PRRSV general RT-rtPCR kit (Anheal assay), for the molecular detection of PRRSV in sera collected from pigs in China. Between June and September 2015, sera were collected from 219 healthy and 104 suspected PRRSV-infected pigs on 4 farms in China. Employing blinding, the 2 assays were run by 2 laboratories (Guangzhou Animal Health Inspection Institute [GAHII] and Sun Yat-sen University [SYSU] laboratories) and compared. Although both assays detected PRRSV with 100% specificity at both laboratories, the sensitivity (95% vs. 78% at GAHII; 94% vs. 72% at SYSU Laboratory) and the reproducibility (kappa value 0.933 vs. 0.931) were slightly better for the ABI assay compared to the Anheal assay.

In this paper, for the first time, the corrosion behavior of 90/10 copper-nickel alloys was investigated systematically by simulating the different sea depths using static weight loss test, XPS depth analysis (argon ion etching), and electrochemical method. The static weight loss test showed that the average corrosion rate increased first, and then decreased with the increase of sea depth. XPS spectra demonstrated that the composition of the corrosion product layer did not change with variation of sea depth. The outer corrosion product was mainly CuO, Cu2O, Cu2Cl, NiO, and γ-FeOOH, while the inner corrosion product was mainly Cu2(OH)3Cl, Cu2O, NiO, Ni(OH)2, and γ-FeOOH. Electrochemical impedance spectroscopy exhibited that the inner corrosion layer played an important role in protecting the alloy.

MicroRNA-26a (miR-26a) has been reported to be involved in the tumorigenesis of several tumors, but its biological function and molecular mechanism in multiple myeloma (MM) are still unknown. In this study, we found that overexpression of miR-26a obviously inhibited MM cell growth, and delayed tumor growth in xenografts. Further studies showed that overexpression of miR-26a induced cell cycle arrest at G0/G1 phase in MM cells. MiR-26a mimic down-regulated the expression levels of CDK6 and E2F1, but up-regulated p53 and p21 expression. In contrast, overexpression of CDK6 decreased the effect of miR-26a mimic on MM cell survival. Moreover, miR-26a targeted CDK6 mRNA and thus suppressed CDK6 protein expression. Overexpression of miR-26a also enhanced the cytotoxic action of doxorubicin against MM. These results demonstrated that miR-26a was involved in the development of MM through regulating CDK6 signaling pathway, and indicated that miR-26a could be as a novel target for anti-tumor therapy in clinic as a single strategy or in combination with other anti-tumor drugs in MM.

This paper introduces the concept of Voice Assistant, the voice recognition service providers, several typical Voice Assistant product, and then the basic working process of the Voice Assistant is described in detail and proposed the technical bottleneck problems in the development of Voice Assistant software.

With the deepening reform of the management system of modern enterprises, the effective use of new technology and science has become increasingly important to every enterprise in order to make themselves in an invincible position in the competition must establish their own set of efficient operation of information management systems, the company embarked on a road of healthy development. Based on this, the paper mainly discusses the use of computer management information systems in the modern enterprises.

Composite material is becoming the key material of aviation industry, in this paper we get the optimal detection parameters of aircraft honeycomb structure by digital ray detection technology after many trials and testing image contrast, using gray linear transformation and reliefs enhancement technology to improve image contraction and sensitivity.

Among the digital monitoring system, MPEG4 encoding compression technology and embedded technologies are widely used, chemical embedded MPEG4 video surveillance system has a broad market prospect and highly advanced technology. In this paper, the MPEG coding standards and on the basis of analysis of the characteristics, given a set of MPEG4 video surveillance system design, and implementation are integrated MPEG4 exposition, after the actual chemical application shows that the system performance stable, real good, do not need to assign someone to manage, scalability is also very good.

Background. Since the introduction of the theory of tumour stem cells (TSCs), the liver cancer stem cell (LCSC)-like cells have become one of the focuses in the research on liver cancer. Materials and methods. In this study, CD90+ cells were applied as the possible LCSC-like cells, and the miRNA and gene expression were analyzed in the CD90+ HepG2 cells. The pilot study showed miR-548c-5p exerted potential effect on the CD90+ HepG2 cells and was thereafter applied for the further study. CD90+ HepG2 cells were assigned to miR-548c-5p mimic transfection group and control group. MTT assay was performed to detect the proliferation of CD90+ HepG2 cells. The migration and invasion abilities were examined by wound healing assay and transwell migration assay, respectively. A detection of apoptosis was performed by fluorescence microscopy. Results. Our results showed that caspase-3 and bcl-2 were down-regulated while caspase-8 was up-regulated in the CD90+ HepG2 cells. Moreover, the miR-548c-5p transfection could down-regulate the expression of β-catenin, Tg737, bcl-2, bcl-XL, and caspase-3, inhibit the proliferation, migration and invasion and promote the apoptosis of the CD90+ HepG2 cells. Conclusions. Our findings indicate the imbalance between apoptosis and anti-apoptosis in the LCSC-like cells, which influence the biological features of LCSC-like cells. miRNA plays a regulatory role in the LCSC-like cells among which miR-548c-5p might be a suppressor.

To investigate IRF6 gene mutation in a van Der Woude syndrome (VWS) family in Henan province.PCR and DNA sequencing was employed to detect the mutation of IRF6.Secondary construction transformation analysis was performed using PIX-Protein Identification software.A CGCTGC(r.279c--t) transversion of IRF6 was identified in condon 6, showing complete segregation with the disease phenotypes and was resulting in changes of the secondary constructure of IRF6.VWS is caused by mutations in IRF6 gene, and IRF6 is closely related to the development of lip, palate and tooth.