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The method for producing polyvinyl alcohol (PVA) by the solution polymerization of vinyl acetate first and then alcoholysis strategy is industrial. Where solvent plays a vital role in control over stereoregularity, molecular weight and its distribution, crystallinity and so on. In this report, when methyl acetate was used as a solvent in the polymerization of vinyl acetate instead of methanol, prepared PVA was characterized by Fourier-transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The results showed that PVA obtained in methyl acetate has a higher content of syndiotactic structure, crystallinity melting temperature and enhanced thermal stability compared with PVA obtained in methanol due to the formation of [PI] - [PI] complex between methyl acetate and vinyl acetate and the enhanced steric hindrance effect during polymerization. Additionally, methyl acetate has a smaller chain transfer constant (1.31 * [10.sup.-4]), which benefits to decrease the branching degree and molecular weight distribution index of PVA. This research provides more ideas for the choice of solvents in the industrial production of polyvinyl alcohol. KEYWORDS branching degree, molecular weight distribution, polyvinyl alcohol, tacticity, vinyl acetate, 1 | INTRODUCTION Polyvinyl alcohol (PVA) is a biodegradable synthetic polymer with excellent characteristics including transparency, gas barrier property, water-solubility, mechanical properties, which has been widely used in various fields [...]

Aiming at the problems of more blind monitoring areas and unable to show the distribution of gas flow field in single point monitoring mode of gas in mining face, based on edge computing technology, a method of constructing gas concentration field in mining face, visual display of gas flow field and monitoring and early warning of abnormal gas emission is proposed. The platform revolutionized the traditional methane monitoring model, replaced single-point monitoring with area monitoring, replaced methane substations with edge computing gateways, and realized global monitoring of methane in coal mining faces, built methane data fields underground, displayed methane cloud diagrams, and captured methane emission abnormally. The specific ideas are as follows: the distribution characteristics of “step rise” and “gradual rise” of methane in mining face are obtained by field measured data. Based on this, a full coverage monitoring scheme of methane is designed, and the full coverage monitoring layout system of methane is completed by using a new MEMS methane sensor; the monitoring data are transmitted to the edge computing gateway by wireless or wired means; edge computing gateway is located in mining roadway, embedded data processing model, single point methane concentration abnormal jump recognition model and periodic abnormal fluctuation discrimination model. The data processing model to build methane digital field, methane dynamic cloud diagrams, the jump model of single point methane concentration anomaly are used to judge the fluctuation of single point methane concentration anomaly, the discrimination by region mode to complete the mining face methane abnormal fluctuation behavior capture. Finally, the macroscopic display of methane concentration field cloud diagram and microscopic capture of abnormal fluctuation of methane concentration are realized.

Starting from the requirement of environmental safety monitoring and early warning in intelligent working face, the monitoring and early warning of five kinds of disasters including water disasters, fire disasters, gas disasters, mine pressure disasters and dust disasters in working face is taken as the main line. By means of information technology, the real-time monitoring and early warning realization of five disasters in intelligent working face are studied. Based on the data source of basic analysis, disaster analysis method and monitoring analysis results, the environmental safety monitoring and early warning of intelligent working face is analyzed.

Populus wulianensis mainly grows in hilly and sloped areas and has strong resistance to adversity. Previous transcriptome studies have shown that a WRKY gene PwuWRKY48 is expression-induced under drought stress. In this study, we aim to characterize the gene's structure and investigate its role in plant drought resistance. The results show that PwuWRKY48 (1113 bp) belongs to a class IIc WRKY subfamily and it was determined as a nuclear localization protein. The gene promoter region contains a variety of cis-elements in relation to stress resistance. Under drought stress, PwuWRKY48 was expression-induced in leaves and stems, 29.7 and 16.6 times those before treatment, respectively. Overexpressing PwuWRKY48 lines were associated with increased activities of peroxidase (POD) and superoxide dismutase (SOD), 2.5 and 1.6 times higher than those of the wild type. While malondialdehyde content (MDA), superoxide anion radical (O2·−), and relative conductivity were decreased by 20%, 30%, and 21.3%, proline and chlorophyll contents increased by 37.5% and 11.2%, respectively. This indicates that PwuWRKY48 efficiently improved the drought tolerance of transgenic plants. PwuWRKY48 can be used as a gene resource for molecular breeding of plant drought resistance. [ABSTRACT FROM AUTHOR]

In view of goaf spontaneous combustion prevention of 12401 fully mechanized working face with large mining height in Shangwan Coal Mine, CO is determined as prediction index gas of coal spontaneous combustion and C2H4 is used as auxiliary index gas to master coal spontaneous combustion through temperature programmed oxidation experiment. Gas in goaf is monitored by laying beam tubes on air return side in goaf of the working face, and spontaneous combustion 'three zones' in goaf were divided according to monitoring results. Heat dissipation zone is 0-32 m away from the working face, spontaneous combustion zone is 32-225 m away from the working face, and suffocation zone is 225 m away from the working face. According to total length of heat dissipation zone and spontaneous combustion zone and the minimum coal spontaneous combustion period, the minimum safe advancing speed of the working face is about 6.4 m/d. The research results can provide reliable basis for formulation of fire prevention measures on the working face.

Changing rule of composite gas indexes under different dry air flow and oxygen concentration was analyzed through coal temperature-programmed experiment. The experimental results show that φ(O2)/(φ(CO)+φ(CO2)) should be selected as gas indexes for coal spontaneous combustion prediction in the case of uncertain dry air flow. φ(O2)/(φ(CO)+φ(CO2)) can be used as gas indexes for coal spontaneous combustion prediction when coal temperature is below 100 °C. φ(C2H4)/φ(CH4) and φ(CO)/φ(CO2) can be used as gas indexes for coal spontaneous combustion prediction when coal temperature exceeds 100 °C. φ(C2H4)/φ(CO) can also be used as gas indexes for coal spontaneous combustion when coal temperature exceeds 160 °C and oxygen volume fraction is approximately 5%.

Attackers exploit vulnerabilities to change RET gadget chains and control the order of program execution, threatening the security of software implementations. For example, memory overflow attacks and remote shellcode attacks will lead to the leak of information. The previous key agreement protocols have not considered the security of protocol implementations at the source code level. As a result, when used on the networks (like wireless sensor networks, SAE/LTE networks, IOT networks, and cloud computing environment), they often suffer from vulnerabilities. To solve these problems, a novel key agreement protocol is proposed on the base of the RET gadget chain in this paper. The novel key agreement protocol not only considers the security of cryptographic techniques and the integrity of the control flow when executing programs, they can also prevent the attacks from the vulnerabilities during implementation at the source code level. At the same time, its security analysis and experiments conducted are presented in this paper. It has been shown in the experiments that the novel key agreement protocol can prevent code reuse attacks in the process of implementation at the source code level, and its performances (like time overheads and security) are better than those of other common key agreement protocols.

A real 3D model of mine ventilation system was built by VENTSIM 3D ventilation dynamic simulation system taking a coal mine as research object. On the basis of obtaining reliable basic ventilation parameters, an accurate simulation of optimal regulation and control scheme of the ventilation system was made. The actual measurement results are in good agreement with the simulation results, and error is very small, so it verified the reliability of optimal regulation and control scheme of ventilation system based on 3D model.

In view of problem of big power consumption, low degree of automation, low accuracy and real-time performance existed in traditional and artificial control method of fireproof and extinguishing by even air pressure, an automatic frequency-conversion control system of fireproof and extinguishing by even air pressure was designed, and composition, operation mode， control method and logic implementation process of the system were introduced. The system adopts theory of local dynamic air pressure balance of multilayer goaf flow field, uses method of automatic frequency-conversion to control local ventilator to change pressure of working face according to differential pressure of working face and upper adjacent goaf, so as to reach the purpose of pressure equalizing of working face and ambient, which realizes automatic control of fireproof and extinguishing by even air pressure of interconnected mining working faces of multilayer goaf.

The Jian'an [TEXT NOT REPRODUCIBLE IN ASCII] (196-220) period witnessed a flourishing of 'presentation and reply' poetry (zengda shi [TEXT NOT REPRODUCIBLE IN ASCII]). (1) Many of these poems were [...]

Many evidences have showed that some intelligence agencies (often called big brother) attempt to monitor citizens' communication by providing coerced citizens a lot of subverted cryptographic algorithms and coercing them to adopt these algorithms. Since legalized services on large number of various applications and system architectures depend on digital signature techniques, in the context some coerced users who use double authentication preventing signatures to design some novel digital signature techniques, have some convincing dissertations to defuse requests from authorities and big brothers creating some corresponding subverted signatures. As rapid progress in quantum computers, National Security Agency advisory memorandum and announcement of National Institute of Standards and Technology procedures from standardization focus on some cryptographic algorithms which are post quantum secure. Motivated by these issues, we design an algorithm substitution attack against Fiat-Shamir family based on lattices (e.g., BLISS, BG, Ring-TESLA, PASSSign and GLP) that are proven post-quantum computational secure. We also show an efficient deterable way to eliminate big brother's threat by leaking signing keys from signatures on two messages to be public. Security proof shows that our schemes satisfy key extraction, undetectability and deterability. Through parameters analysis and performance evaluation, we demonstrate that our deterring subverted Fiat-Shamir signature is practical, which means that it can be applied to privacy and protection in some system architectures. [ABSTRACT FROM AUTHOR]

Background/Aims: Anti-tumor vaccines have been shown to be effective in cancer therapeutics ever since the anti-HPV vaccine was developed. Compared to conventional chemotherapy, anti-tumor vaccines can specifically target cancer cells and they have lower side effects. We developed a recombinant vaccinia virus (VACV) (Western Reserve) WR strain, and we tested its anti-tumor effects in an animal model. Methods: A recombinant VACV WR strain expressing mutant survivin T34A (SurT34A) and FilC was constructed and validated. Its oncolytic effect was tested in vitro using a CCK-8 assay, and its tolerance and anti-tumor effects were tested in a murine gastric cancer model. The proportion of lymphocytes in the spleen and tumor was determined after antibody-mediated immuno-depletion. Results: The recombinant VACV showed a stronger replication ability in tumor cells, and it was safe in vivo, even at high doses. The combination of vv-SurT34A and vv-FilC resulted in a stronger anti-tumor effect compared to either construct alone. However, the inhibitory effect of vv-SurT34A was stronger than the combination. The recombinant VACV activated the host immune response, as indicated by lymphocyte infiltration in the spleen and tumor tissues. Conclusion: The recombinant VACV WR strain expressing SurT34A and FilC is a safe and effective anti-tumor vaccine. [ABSTRACT FROM AUTHOR]

Background: In recent years, long non-coding RNAs (lncRNAs) have been shown to play a critical regulatory role in cancer biology. However, the contribution of lncRNAs to papillary thyroid cancer (PTC) remains largely unknown. Methods: RNA sequencing and quantitative reverse transcription polymerase chain reaction were used to detect and verify changes to the transcriptome profile in 12 PTC tissues compared to paired normal adjacent tissues. The statistical correlation between differentially expressed lncRNAs and clinicopathologic characteristics was analyzed, and potential lncRNA functions were predicted by examining annotations for the co-expressed mRNAs. Furthermore, the specific subgroup patterns of the PTC transcriptome remodeled by BRAF mutations were also analyzed. Results: A total of 188 lncRNAs and 505 mRNAs were differentially expressed in 50% or more of the PTC tissues (fold change >2; p < 0.05) as assessed by RNA-sequencing compared with paired normal adjacent tissues. Forty-seven lncRNAs and 39 mRNAs were verified in 31 pairs of PTC specimens using quantitative reverse transcription polymerase chain reaction, and the results were consistent with the RNA sequencing data. The lncRNAs NONHSAT076747 and NONHSAT122730 were associated with lymph node metastasis, and NONHSAG051968 expression was negatively correlated with tumor size. A co-expression network between differentially expressed lncRNAs and protein-coding RNAs was constructed and analyzed, and functional analysis suggested that the differentially expressed genes mainly participate in ECM-receptor interactions and the focal adhesion pathway. Furthermore, a specific PTC transcriptome subtype pattern stratified by BRAF mutation was also uncovered. The p53 signaling pathway was the most highly enriched pathway among the BRAF mutation-related genes. Conclusions: This study reveals specific changes to the lncRNA profile associated with PTC, and provides new insight into its pathogenesis. The PTC-associated lncRNAs NONHSAG051968, NONHSAT076747, and NONHSAT122730 might be potential diagnostic and therapeutic targets for PTC patients, and lncRNAs with subtype-specific expression stratified by BRAF mutation might be significant in individual molecular subtypes. [ABSTRACT FROM AUTHOR]

ABSTRACT For the first time, the main characteristics of the polymeric materials are considered for understanding their possible application in ecological sand-fixing. In this investigation, two emulsions, named as E2, a poly(vinyl acetate) emulsion, and E7, a vinyl acetate-ethylene copolymer emulsion, have been selected for a series of tests related to the practical requirements for ecological sand-fixing. Besides the sand-fixing properties and the thermal aging and freeze-thaw stabilities of the emulsions, their effects in increasing the growth of both microbes and plants in sandy lands have been evaluated by field experiments in Kerqin Sandy Land of China, and the relationship between the performance and structure of the two emulsions has also been described. The experimental results show that both emulsions could significantly improve the compressive strength of treated sand and could withstand the changes in temperature of the Kerqin Sandy Land. However, different effects were exhibited in promoting the growth of microbes, in facilitating the accumulation of organic fertilizer and soluble salt, and in increasing the crop yield. All of the differences are attributed to their different molecular chain structures. These findings suggest that the structure of a polymeric emulsion should be the first consideration for the materials used in ecological sand-fixing, and ecological sand-fixing is a successful method for the stabilization of sandy land and the restoration of desertified land in semiarid regions. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44102 [ABSTRACT FROM AUTHOR]

Down-regulation of the microRNA let-7c plays an important role in the pathogenesis of human hepatocellular carcinoma (HCC). The aim of the present study was to determine whether the cell cycle regulator CDC25A is involved in the antitumor effect of let-7c in HCC. The expression levels of let-7c in HCC cell lines were examined by quantitative real-time PCR, and a let-7c agomir was transfected into HCC cells to overexpress let-7c. The effects of let-7c on HCC proliferation, apoptosis and cell cycle were analyzed. The in vivo tumor-inhibitory efficacy of let-7c was evaluated in a xenograft mouse model of HCC. Luciferase reporter assays and western blotting were conducted to identify the targets of let-7c and to determine the effects of let-7c on CDC25A, CyclinD1, CDK6, pRb and E2F2 expression. The results showed that the expression levels of let-7c were significantly decreased in HCC cell lines. Overexpression of let-7c repressed cell growth, induced cell apoptosis, led to G1 cell cycle arrest in vitro, and suppressed tumor growth in a HepG2 xenograft model in vivo. The luciferase reporter assay showed that CDC25A was a direct target of let-7c, and that let-7c inhibited the expression of CDC25A protein by directly targeting its 3ʹ UTR. Restoration of CDC25A induced a let-7c-mediated G1-to-S phase transition. Western blot analysis demonstrated that overexpression of let-7c decreased CyclinD1, CDK6, pRb and E2F2 protein levels. In conclusion, this study indicates that let-7c suppresses HCC progression, possibly by directly targeting the cell cycle regulator CDC25A and indirectly affecting its downstream target molecules. Let-7c may therefore be an effective therapeutic target for HCC. [ABSTRACT FROM AUTHOR]

In the English-speaking world, translations of Tao Yuanming's works date back to as early as the nineteenth century. These translations, which aimed both at general audience and scholarly community, are important documents of Tao Yuanming studies in the West; they also shed much light on Western sinology in general. This essay is a systematic survey and analysis of English translations of Tao Yuanming's poetry. [ABSTRACT FROM AUTHOR]

Recent work has revealed an essential involvement of soluble CD40L (sCD40L) in inflammation and vascular disease. Activated platelets are the major source of sCD40L, which has been implicated in platelet and leukocyte activation, although its exact functional impact on leukocyte-platelet interactions and the underlying mechanisms remain undefined. We aimed to determine the impact and the mechanisms of sCD40L on neutrophils. We studied neutrophil interactions with activated, surface-adherent platelets as a model for leukocyte recruitment to the sites of injury. Our data show that CD40L contributes to neutrophil firm adhesion to and transmigration across activated surface-adherent platelets, possibly through two potential mechanisms. One involves the direct interaction of ligand-receptor (CD40L-CD40), i.e., platelet surface CD40L interaction with neutrophil CD40; another involves an indirect mechanism, i.e. soluble CD40L stimulates activation of the leukocyte-specific β2 integrin Mac-1 in neutrophils and thereby further promotes neutrophil adhesion and migration. Activation of the integrin Mac-1 is known to be critical for mediating neutrophil adhesion and migration. sCD40L activated Mac-1 in neutrophils and enhanced neutrophil-platelet interactions in wild-type neutrophils, but failed to elicit such responses in CD40-deficient neutrophils. Furthermore, our data show that the protein kinase C zeta (PKCζ) is critically required for sCD40L-induced Mac-1 activation and neutrophil adhesive function. sCD40L strongly stimulated the focal clustering of Mac-1 (CD11b) and the colocalization of Mac-1 with PKCζ in wild-type neutrophils, but had minimal effect in CD40-deficient neutrophils. Blocking PKCζ completely inhibited sCD40L-induced neutrophil firm adhesion. Moreover, sCD40L strongly stimulates neutrophil oxidative burst via CD40-dependent activation of PI3K/NF-KB, but independent of Mac-1 and PKCζ. These findings may contribute to a better understanding of the underlying mechanisms by which sCD40L/CD40 pathway contributes to inflammation and vascular diseases. [ABSTRACT FROM AUTHOR]

Aims To validate whether the anti-cancer effect of micro RNA-122 ( miR-122) on hepatocellular carcinoma ( HCC) is mediated through regulating Wnt/β-catenin signalling pathways. Methods The expression levels of miR-122 in HCC tissues and varied hepatoma cells were quantified by real-time PCR. MiR-122 agomir was transfected into HepG2, Hep3B cells to over-express miR-122. The effect of over-expression miR-122 on proliferation and apoptosis of HepG2 and Hep3B cells was evaluated using CCK-8 kit and flow cytometer respectively. The 3′- UTR segments of Wnt1 containing the miR-122 binding sites were amplified by PCR and the luciferase activity in the transfected cells was assayed. Wnt1 mRNA level was quantified using RT-PCR. Protein levels of Wnt1, β-catenin and TCF-4 were detected using Western blotting. Results In comparison with the expression level of miR-122 in para-cancerous tissues or Chang liver cell, the expression level in HCC tissues or varied hepatoma cells was significantly decreased ( P < 0.05). Over-expression of miR-122 significantly inhibited the proliferation ( P < 0.05), and promoted the apoptosis of HepG2 and Hep3B cells. Over-expressed miR-122 down-regulated the protein levels of Wnt1, β-catenin and TCF-4 ( P < 0.05). MiR-122 suppressed the luciferase activity of the pmiR-Wnt1-wt by approximately 50% compared with the negative control, while mutation or removal of the miR-122 binding site using si RNA or mir-122 inhibitor blocked the suppressive effect ( P < 0.05). Conclusions MiR-122 expression is down-regulated in human HCC. Over-expression of miR-122 inhibits HCC cell growth and promotes the cell apoptosis by affecting Wnt/β-catenin- TCF signalling pathway. [ABSTRACT FROM AUTHOR]

Abstract: Accumulating evidence indicates that various aspects of angiogenesis, such as proliferation, migration, and morphogenesis of endothelial cells, can be regulated by specific miRNAs in an endothelial-specific manner. As novel molecular targets, miRNAs have a potential value for treatment of angiogenesis-associated diseases such as cancers, inflammation, and vascular diseases. In this article, we review the latest advances in the identification and validation of angiogenesis-regulatory miRNAs and their targets, and discuss their roles and mechanisms in regulating endothelial cell function and angiogenesis. [Copyright &y& Elsevier]

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Abstract Background The miR-129-5p has been reported to be aberrant expression and exert vital roles in tumor progression of various malignancies. However, the effects on EMT in gastric cancer and its precise molecular mechanism in gastric cancer remain unclear. Methods and materials RT-qPCR was performed to evaluate the expression level of miR-129-5p and HMGB1 in cell lines. Cell proliferation was detected via CCK-8. The epithelial mesenchymal transition (EMT) related proteins and the expression of HMGB1 were detected by western blot analysis. Luciferase assays were used to validate binding seeds between miR-129-5p and HMGB1. Results miR-129-5p was downregulated in gastric cancer cells compared with GES-1. At the same time EMT was promoted in gastric cancer cells compared to GES-1. Overexpression of miR-129-5p inhibited EMT and proliferation. MiR-129-5p negatively and directly targeted HMGB1. HMGB1 was upregulated in gastric cancer cells and HMGB1 knocked-down inhibited EMT and cell proliferation. Conclusion Taken together, upregulation of miR-129-5p associated with gastric cancer proliferation and EMT, and serves as a potential diagnostic and therapeutic target via miR-129-5p/HMGB1 pathway in gastric cancer. [ABSTRACT FROM AUTHOR]

Highlights: [•] miR-29a may be stimulated by hypoxia in HUVEC. [•] miR-29a regulates cell cycle, proliferation and tube network formation of HUVEC. [•] HMG box-containing protein-1(HBP1) is a direct target of miR-29a. [•] miR-29a has a potential value for treating angiogenesis-associated diseases. [ABSTRACT FROM AUTHOR]

Abstract: Smooth muscle cell (SMC) migration involves interactions of integrin receptors with extracellular matrix (ECM) and is an important process of neointimal formation in atherosclerosis and restenosis after vascular interventions. Previous studies have shown that periostin (PN), a novel ECM protein, is upregulated in rat carotid artery after balloon injury, and growth factor-stimulated expression of PN promotes SMC migration in vitro. Here, we address the mechanism by which PN–integrin interaction mediates SMC migration in vitro. Aortic SMCs isolated from PN null mice exhibited a significantly reduced ability to migrate and proliferate in vitro. Endogenous PN protein was absent and very low in the culture medium from the primary cultures of PN−/− and wildtype SMCs, respectively. In both types of SMCs, adenovirus-mediated overexpression of HA-tagged PN to a similar extent, which induced a robust cell migration concomitantly with an increase in β3-integrin expression and phosphorylation of FAK (Tyr397). Furthermore, in cultured human SMCs, specific integrin blocking antibodies showed that interactions of PN-ανβ3 and PN-ανβ5, but not PN-β1 integrins, are required for SMC migration. Inhibition of FAK signaling by overexpression of an endogenous FAK inhibitor termed FRNK (FAK-related nonkinase) significantly attenuated FAK (Tyr397) phosphorylation and the SMC migration induced by PN. These results reveal a mechanism whereby PN mediates vascular SMC migration through an interaction with alphaV-integrins (mainly ανβ3) and subsequent activation of FAK pathway. [Copyright &y& Elsevier]

Background: Platycladus orientalis , as an important plant for ecological protection, is a pioneer tree species for afforestation in arid and barren mountainous areas. Lignin has the functions of water and soil conservation, strengthening plant mechanical strength and resisting adverse environmental effects and plays an important role in the ecological protection benefits of P. orientalis ., Methods: In this study, annual dynamic observations of the lignin content in roots, stems and leaves of one-year-old seedlings of a P. orientalis half-sib family were carried out, and combined transcriptome and metabolome analyses were carried out during three key stages of P. orientalis stem development., Results: The lignin contents in roots, stems and leaves of P. orientalis showed extremely significant spatiotemporal differences. In the stems, lignin was mainly distributed in the cell walls of the pith, xylem, phloem, pericyte, and epidermis, with differences in different periods. A total of 226 metabolites were detected in the stem of P. orientalis , which were divided into seven categories, including 10 synthetic precursor compounds containing lignin. Among them, the content of coniferyl alcohol was the highest, accounting for 12.27% of the total content, and caffeyl alcohol was the lowest, accounting for 7.05% only. By annotating the KEGG functions, a large number of differentially expressed genes and differential metabolites were obtained for the comparison combinations, and seven key enzymes and 24 related genes involved in the process of lignin synthesis in P. orientalis were selected., Conclusions: Based on the results of the metabolic mechanism of lignin in P. orientalis by biochemical, anatomical and molecular biological analyzes, the key regulatory pathways of lignin in P. orientalis were identified, which will be of great significance for regulating the lignin content of P. orientalis and improving the adaptability and resistance of this plant., Competing Interests: The authors declare there are no competing interests., (©2022 Li et al.)

Objective Medullary thyroid carcinoma (MTC) is classified as either sporadic or inherited. This study was performed to analyze the risk factors for cervical lymph node metastases and predict the indication for prophylactic lateral neck dissection in patients with sporadic MTC. Methods Sixty-five patients with sporadic MTC were retrospectively reviewed. Univariate analysis with the chi-square test and multiple logistic regression analysis were applied to identify the clinicopathological features (sex, age, tumor size, number of tumor foci, capsule or vascular invasion, and others) associated with cervical lymph node metastases. Results The metastasis rates in the central and lateral compartments were 46.2% (30/65) and 40.0% (26/65), respectively. The incidence of cervical lymph node metastases was significantly higher in patients with a tumor size of >1 cm, tumor multifocality, and thyroid capsule invasion. Only thyroid capsule invasion was an independent predictive factor for central compartment metastases and lateral neck metastases. The possibility of central compartment metastases was significantly higher when the preoperative serum carcinoembryonic antigen concentration was >30 ng/mL (60.0% vs. 34.3%). Conclusions MTC is associated with a high incidence of cervical lymph node metastases. Prophylactic lateral node dissection is necessary in patients with thyroid capsule invasion or a high serum carcinoembryonic antigen concentration.

Hepatoid adenocarcinoma (HAC), an extrahepatic tumor, has notable morphological similarities to hepatocellular carcinoma, which has been reported in gastrointestinal tract organs, including the rectum, gallbladder, lung, ovary and urinary bladder. HAC of the stomach (GHAC) is a rare variant of gastric cancer, characterized by aggressive behavior and extremely poor prognosis. Correct diagnosis depends on clinicopathological and immunohistochemical studies. In the present study, we reported nine cases of GHAC who were treated in the First Affiliated Hospital of Zhejiang University, China, from January 2009 to December 2013. All patients underwent radical gastrectomy; among them, one patient had stage I, one had stage II and seven had stage III. Elevated serum α-fetoprotein was observed in eight cases. Until now, only one patient has succumbed, four patients have liver metastases, one has lung metastasis and four remain disease-free. Relatively longer survival requires accurate diagnosis at an earlier stage and active multimodality treatment, including radical gastrectomy and adjuvant chemotherapy.

Let-7 family members have been identified as tumor-suppressing microRNAs, which are important in human hepatocellular carcinoma (HCC). These family members may function differently as a result of different base sequences at the 3'end. The aim of this study was to determine the antitumor effects of miR-let-7g/i (let-7g/i) on HCC cells and to investigate whether let-7g and let-7i have a combinatorial effect on HCC. The expression levels of let-7g/i in hepatoma cells were determined by quantitative reverse transcription polymerase chain reaction. In addition, a 5-ethynyl-2'-deoxyuridine retention assay and flow cytometry analysis were used to detect the effect of let-7g/i on the proliferation and apoptosis of BEL-7402 cells, respectively. The expression of anti-apoptotic protein B-cell lymphoma-extra large (Bcl-xL) was analyzed using western blot analysis. The results revealed that the expression levels of let-7g/i were significantly decreased in HCC cell lines when compared with L-02 cells. Furthermore, the overexpression of let-7g/i significantly suppressed DNA replication, inhibited cell proliferation and promoted apoptosis of BEL-7402 hepatoma cells. The expression of the anti-apoptotic protein, Bcl-xL, was inhibited by the combined role of let-7g and let-7i. We hypothesize that let-7g and let-7i exhibit a concurrent effect to regulate cell proliferation and the apoptosis of hepatoma cells, and this function is mediated by the Bcl-xL protein.

Wnt/β-catenin signaling pathway has a close relationship with cancer and is abnormally activated in many human cancers. Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related death worldwide, but the molecular mechanisms of HCC are still poorly understood. Current studies indicate that Wnt/β-catenin signaling pathway plays a key role in the development and progression of HCC. Validating the role and mechanism of Wnt/β-catenin signaling pathway in HCC will provide a theoretical basis for early diagnosis and treatment of HCC. In this review, we summarize the role of Wnt/β-catenin signaling pathway in HCC and the progress of current researches.

We present a case of a life-threatening almost complete airway obstruction resulting from poorly differentiated thyroid carcinoma in a 48-year-old male. Airway obstruction may lead to unexpected mortality by suffocation and patients with poorly differentiated thyroid carcinoma usually have a fast deterioration and fatal outcome. In the case presented, we describe a safe and effective treatment strategy. Assisted by femoro-femoral cardiopulmonary bypass oxygenation, a tracheal stent was implanted successfully. Following surgery there were no complications, and chemoradiotherapy resulted in the relief of obstructing symptoms and improved the quality of life of the patient. This case indicates that femoro-femoral cardiopulmonary bypass provides adequate oxygen support to undergo further management and that tracheal stent implant is an effective emergent measure to relieve severe airway obstruction in patients with poorly differentiated thyroid carcinoma.