Improvement Of Centrifugal Compressor Reliability Handling High Pressure And High Density Gas.

LecturePg. 51-60Centrifugal compressors handling high pressure and high density gas can sometimes encounter trouble such as rotor instability and impeller resonance vibration while in operation. In order to eliminate these problems, various analytical and experimental studies were carried out. Shop verification tests were performed to corroborate the studies and to confirm demonstrated improvement in the reliability of the compressors. Reliability improvements in the above two areas-namely compressor rotor stability and impeller resonanceare described in this paper, with specific reference to newly developed knowledge and technology for the benefit of interested centrifugal compressor users and turbomachinery engineers

The Soluble Factor from Oral Cancer Cell Lines Inhibits Interferon-γ Production by OK-432 via the CD40/CD40 Ligand Pathway

OK-432 is a potent immunotherapy agent for several types of cancer, including oral cancer. We previously reported that OK-432 treatment can induce the production of high levels of IFN-γ from peripheral blood mononuclear cells (PBMCs). Moreover, the IFN-γ production from PBMCs by OK-432 is impaired by conditioned media (CM) from oral cancer cells. To determine the inhibitory mechanism of IFN-γ production by CM, the genes involved in IFN-γ production was retrieved by cDNA microarray analysis. We found that CD40 played a key role in IFN-γ production via IL-12 production. Although the expression levels of CD40 were upregulated by OK-432 treatment in PBMCs, CM inhibited OK-432-induced CD40 expression. These findings suggest that uncertain soluble factor(s) in CM may suppress IFN-γ production via the CD40/CD40L–IL-12 axis in PBMCs.(1) Background: OK-432 is a penicillin-killed, lyophilized formulation of a low-toxicity strain (Su) of Streptococcus pyogenes (Group A). It is a potent immunotherapy agent for several types of cancer, including oral cancer. We previously showed that (i) OK-432 treatment induces a high amount of IFN-γ production from peripheral blood mononuclear cells (PBMCs), and (ii) conditioned medium (CM) from oral cancer cells suppresses both the IFN-γ production and cytotoxic activity of PBMCs driven by OK-432. The aim of this study was to determine the inhibitory mechanism of OK-432-induced IFN-γ production from PBMCs by CM. (2) Methods: We performed cDNA microarray analysis, quantitative RT-PCR, and ELISA to reveal the inhibitory mechanism of CM. (3) Results: We found that CD40 plays a key role in IFN-γ production via IL-12 production. Although OK-432 treatment upregulated the expression levels of the IL-12p40, p35, and CD40 genes, CM from oral cancer cells downregulate these genes. The amount of IFN-γ production by OK-432 treatment was decreased by an anti-CD40 neutralizing antibody. (4) Conclusions: Our study suggests that uncertain soluble factor(s) produced from oral cancer cells may inhibit IFN-γ production from PBMCs via suppressing the CD40/CD40L–IL-12 axis

Prognostic value of p-EMT-related genes in HNSCC

Objective: Recent studies have revealed that the ability of cancer cells to undergo intermediate state of EMT, partial EMT (p-EMT) poses a higher metastatic risk rather than complete EMT. Here we examined the prognostic value of p-EMT-related genes in head and neck squamous cell carcinoma (HNSCC) by bioinformatics approaches. Materials and Methods: We used RNA-seq data of 519 primary HNSCC cases obtained from TCGA database. We compared the expression of p-EMT-related genes in HNSCC tissues with normal tissues. We evaluated the prognostic value of p-EMT-related genes in HNSCC cases by Log-rank test. We examined the expression of p-EMT-, EMT-, and epithelial differentiation-related genes by qPCR. Results: Among p-EMT-related genes that were highly expressed in HNSCC cases, high expression of SERPINE1, ITGA5, TGFBI, P4HA2, CDH13, and LAMC2 was significantly correlated with poor survival of HNSCC patients. By gene expression pattern, HNSCC cell lines were classified into three groups; epithelial phenotype, EMT-phenotype, and p-EMT phenotype. Conclusions: Our findings suggest that p-EMT program may be involved in poor prognosis of HNSCC. SERPINE1, ITGA5, TGFBI, P4HA2, CDH13, and LAMC2 can be used for a prognostic marker. Moreover, HNSCC cells with p-EMT phenotype can be a useful model for investigating a nature of p-EMT

Conversion from epithelial to partial-EMT phenotype by Fusobacterium nucleatum infection promotes invasion of oral cancer cells

The ability of cancer cells to undergo partial-epithelial mesenchymal transition (p-EMT), rather than complete EMT, poses a higher metastatic risk. Although Fusobacterium nucleatum mainly inhabits in oral cavity, attention has been focused on the F. nucleatum involvement in colorectal cancer development. Here we examined the p-EMT regulation by F. nucleatum in oral squamous cell carcinoma (OSCC) cells. We cultured OSCC cells with epithelial, p-EMT or EMT phenotype with live or heat-inactivated F. nucleatum. Expression of the genes involved in epithelial differentiation, p-EMT and EMT were examined in OSCC cells after co-culture with F. nucleatum by qPCR. Cell growth and invasion of OSCC cells were also examined. Both live and heat-inactivated F. nucleatum upregulated the expression of p-EMT-related genes in OSCC cells with epithelial phenotype, but not with p-EMT or EMT phenotype. Moreover, F. nucleatum promoted invasion of OSCC cells with epithelial phenotype. Co-culture with other strains of bacteria other than Porphyromonas gingivalis did not alter p-EMT-related genes in OSCC cells with epithelial phenotype. F. nucleatum infection may convert epithelial to p-EMT phenotype via altering gene expression in OSCC. Oral hygiene managements against F. nucleatum infection may contribute to reduce the risk for an increase in metastatic ability of OSCC

Involvement of the OTUB1-YAP1 axis in driving malignant behaviors of head and neck squamous cell carcinoma

Background: Comprehending the molecular mechanisms underlying head and neck squamous cell carcinoma (HNSCC) is vital for the development of effective treatment strategies. Deubiquitinating enzymes (DUBs), which regulate ubiquitin-dependent pathways, are potential targets for cancer therapy because of their structural advantages. Here we aimed to identify a potential target for HNSCC treatment among DUBs. Methods: A screening process was conducted using RNA sequencing data and clinical information from HNSCC patients in the TCGA database. A panel of 88 DUBs was analyzed to identify those associated with poor prognosis. Subsequently, HNSCC cells were modified to overexpress specific DUBs, and their effects on cell proliferation and invasion were evaluated. In vivo experiments were performed to validate the findings. Results: In HNSCC patients, USP10, USP14, OTUB1, and STAMBP among the screened DUBs were associated with a poor prognosis. Among them, OTUB1 showed the most aggressive characteristics in both in vitro and in vivo experiments. Additionally, OTUB1 regulated the stability and nuclear localization of YAP1, a substrate involved in cell proliferation and invasion. Notably, OTUB1 expression exhibited a positive correlation with the HNSCC-YAP score in HNSCC cells. Conclusions: This study highlights the critical role of OTUB1 in HNSCC progression via modulating YAP1. Targeting the OTUB1-YAP1 axis holds promise as a potential therapeutic strategy for HNSCC treatment

Biphasic Aire expression in early embryos and in medullary thymic epithelial cells before end-stage terminal differentiation

The roles of autoimmune regulator (Aire)–expressing medullary thymic epithelial cells (mTECs) in the organization of the thymic microenvironment for establishing self-tolerance are enigmatic. We sought to monitor the production and maintenance of Aire-expressing mTECs by a fate-mapping strategy in which bacterial artificial chromosome transgenic (Tg) mice expressing Cre recombinase under the control of the Aire regulatory element were crossed with a GFP reporter strain. We found that, in addition to its well recognized expression within mature mTECs, Aire was expressed in the early embryo before emergence of the three germ cell layers. This observation may help to explain the development of ectodermal dystrophy often seen in patients with AIRE deficiency. With the use of one Tg line in which Cre recombinase expression was confined to mTECs, we found that Aire+CD80high mTECs further progressed to an Aire−CD80intermediate stage, suggesting that Aire expression is not constitutive from after its induction until cell death but instead is down-regulated at the beginning of terminal differentiation. We also demonstrated that many mTECs of Aire-expressing lineage are in close contact with thymic dendritic cells. This close proximity may contribute to transfer of tissue-restricted self-antigens expressed by mTECs to professional antigen-presenting cells

Numerical simulations on the relative importance of starbursts and AGN in ultra-luminous infrared galaxies

We investigate the relative importance of starbursts and AGN in nuclear activities of ultra-luminous infrared galaxies (ULIRGs) based on chemodynamical simulations combined with spectrophotometric synthesis codes. We numerically investigate both the gas accretion rates (m_acc) onto super massive black holes (SMBHs) and the star formation rates (m_sf) in ULIRGs formed by gas-rich galaxy mergers and thereby discuss what powers ULIRGs. Our principal results, which can be tested against observations, are as follows. (1) ULIRGs powered by AGN can be formed by major merging between luminous, gas-rich disk galaxies with prominent bulges containing SMBHs, owing to the efficient gas fuelling m_acc > 1 M_sun/yr of the SMBH. AGN in these ULIRGs can be surrounded by compact poststarburst stellar populations (e.g., A-type stars). (2) ULIRGs powered by starbursts with m_sf ~ 100 M_sun/yr can be formed by merging between gas-rich disk galaxies with small bulges having the bulge-to-disk-ratio (f_b) as small as 0.1. (3) The relative importance of starbursts and AGN can depend on physical properties of merger progenitor disks, such as f_b, gas mass fraction, and total masses. For example, more massive galaxy mergers are more likely to become AGN-dominated ULIRGs. (4) For most models, major mergers can become ULIRGs, powered either by starbursts or by AGN, only when the two bulges finally merge. Interacting disk galaxies can become ULIRGs with well separated two cores (> 20kpc) at their pericenter when they are very massive and have small bulges. (5) Irrespective of the choice of model, interacting/merging galaxies show the highest accretion rates onto the central SMBHs, and the resultant rapid growth of the SMBHs occur when their star formation rates are very high.Comment: 18 pages, 15 figures (f1.jpg for color figure of figure 1), accepted in MNRA

Paradoxical development of polymyositis-like autoimmunity through augmented expression of autoimmune regulator (AIRE)

Autoimmunity is prevented by the function of the autoimmune regulator [AIRE (Aire in mice)], which promotes the expression of a wide variety of tissue-restricted antigens (TRAs) from medullary thymic epithelial cells (mTECs) and from a subset of peripheral antigen-presenting cells (APCs). We examined the effect of additive expression of human AIRE (huAIRE) in a model of autoimmune diabetes in NOD mice. Unexpectedly, we observed that mice expressing augmented AIRE/Aire developed muscle-specific autoimmunity associated with incomplete maturation of mTECs together with impaired expression of Aire-dependent TRAs. This led to failure of deletion of autoreactive T cells together with dramatically reduced production of regulatory T cells in the thymus. In peripheral APCs, expression of costimulatory molecules was augmented. We suggest that levels of Aire expression need to be tightly controlled for maintenance of immunological tolerance. Our results also highlight the importance of coordinated action between central tolerance and peripheral tolerance under the common control of Aire

Contribution of Three Different Regions of Isocitrate Dehydrogenases from Psychrophilic and Psychrotolerant Bacteria to Their Thermal Properties

Monomeric isocitrate dehydrogenases of a psychrophilic bacterium, Colwellia maris, and a psychrotolerant bacterium, Pseudomonas psychrophila, (CmIDH and PpIDH) are cold-adapted and mesophilic, respectively. On the other hand, previous studies revealed that the monomeric IDH of Azotobacter vinelandii (AvIDH) is also mesophilic and the regions 2 and 3 among three regions of this enzyme are involved in the thermal properties. Therefore, to examine whether the region(s) responsible for the mesophilic properties are common between PpIDH and AvIDH, the genes of chimeric IDHs exchanging three regions of PpIDH and CmIDH in various combinations were constructed and overexpressed as His-tagged recombinant proteins in the Escherichia coli cells, and the chimeric and wild-type PpIDH and CmIDH were purified with Ni-chelating affinity column chromatography. The swapping chimeras of the regions 2 or 3 in PpIDH and CmIDH showed lower and higher optimum temperatures for activities and their thermostabilities than the wild-type ones, respectively. On the other hand, the exchange of the respective region 1 hardly influenced these properties of the two IDHs. Therefore, the regions 2 and 3 of the two IDHs were confirmed to be involved in their thermal properties. These results were coincident with those of the previous study on chimeric IDHs between AvIDH and CmIDH, indicating that the common regions of AvIDH and PpIDH are responsible for their mesophilic properties and the amino acid residues involved in their thermal properties are present in the regions 2 and 3