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The tumor suppressor p53 plays a central role in cellular stress responses by regulating transcription of multiple target genes. The temporal dynamics of p53 are thought to be important for its function: it encode input information and are decoded to induce distinct cellular phenotypes. However it remains unclear to what extent the temporal dynamics of p53 reflects the activity of p53-induced gene expression. In this study, we report a multiplexed reporter system that allows us to visualize the transcriptional activity of p53 at the single cell level. Our reporter system features simple and sensitive observation of the transcriptional activity of endogenous p53 to the response elements of various target genes. Using this system, we show that the transcriptional activation of p53 exhibits strong cell-to-cell heterogeneity. The transcriptional activation of p53 by etoposide is highly dependent on the cell cycle but not by UV-C. Finally, we show that our reporter system allows simultaneous visualization of the transcriptional activity of p53 and cell cycle. Our reporter system can thus be a useful tool for studying biological processes involving the p53 signaling pathway.Summary statementTumor suppressor protein p53 is one of the hub factor of the cellular stress responses. Our novel reporter system allows us to visualize the transcriptional activity of endogenous p53 easily and precisely.

Background Pneumonia is a common cause of illness and death of the elderly in Japan. Its prevalence is escalating globally with the aging of population. To describe the latest trends in pneumonia hospitalizations, especially aspiration pneumonia (AP) cases, we assessed the clinical records of pneumonia patients admitted to core acute care hospitals in Miyagi prefecture, Japan. Methods A retrospective multi-institutional joint research was conducted for hospitalized pneumonia patients aged ≥20 years from January 2019 to December 2019. Clinical data of patients were collected from the medical records of eight acute care hospitals. Results Out of the 1,800 patients included in this study, 79% of the hospitalized pneumonia patients were aged above 70 years. The most common age group was in the 80s. The ratio of AP to total pneumonia cases increased with age, and 692 out of 1,800 patients had AP. In univariate analysis, these patients had significantly older ages, lower body mass index (BMI), a lower ratio of normal diet intake and homestay before hospitalization, along with more AP recurrences and comorbidities. During hospitalization, AP patients had extended fasting periods, more swallowing assessments and interventions, longer hospitalization, and higher in-hospital mortality rate than non-AP patients. A total of 7% and 2% AP patients underwent video endoscopy and video fluorography respectively. In multivariate analysis, lower BMI, lower C-reactive protein, a lower ratio of homestay before hospitalization, a higher complication rate of cerebrovascular disease, dementia, and neuromuscular disease were noted as a characteristic of AP patients. Swallowing interventions were performed for 51% of the AP patients who had been hospitalized for more than two weeks. In univariate analysis, swallowing intervention improved in-hospital mortality. Lower AP recurrence before hospitalization and a lower ratio of homestay before hospitalization were indicated as characteristics of AP patients of the swallowing intervention group from multivariate analysis. Change in dietary pattern from normal to modified diet was observed more frequently in the swallowing intervention group. Conclusion AP accounts for 38.4% of all pneumonia cases in acute care hospitals in Northern Japan. The use of swallowing evaluations and interventions, which may reduce the risk of dysphagia and may associate with lowering mortality in AP patients, is still not widespread.

Methyl 2-[1-[(tert-butoxycarbonyl)amino]ethyl]-4-methyloxazole-5-carboxylate (1) was synthesized with high optical purity via a Pd–catalyzed amide coupling with vinyl triflate with subsequent oxazole formation. The latter reaction proceeds via bromination of an enamide with NBS and DBU-promoted cyclization. The oxazole subunit positional isomer in a macrocyclic azole peptide was obtained in a good yield without racemization. The scope and limitations of this reaction were also investigated.

Complete elucidation of the phase behavior of phospholipid bilayers requires information on the subtransition from the lamellar crystal (L c ) phase to the gel phase. However, for bilayers of saturated diacylphosphatidylcholines (C n PCs), especially longer chain homologs, equilibration in the L c phase is known to be very slow. In this study, bilayer phase transitions of three C n PCs with longer acyl chains, C19PC, C20PC and C21PC, were observed by differential scanning calorimetry under atmospheric pressure and by light-transmittance measurements under high pressure. Using lipid samples treated by thermal annealing enabled the observation of the sub-, pre- and main transitions of the C19PC and C20PC bilayers under atmospheric pressure. Only the pre- and main transitions could be observed for the C21PC bilayer due to very slow kinetics of the L c phase formation for lipids with long acyl chains. The temperature and pressure phase diagrams constructed and phase-transitions quantities (enthalpy, entropy and volume changes) evaluated for these bilayers were compared with one another and with those of bilayers of the C n PC homologs examined in previous studies. These results allowed us (1) to clarify the temperature- and pressure-dependent phase sequence and phase stability of the C n PC ( n = 12–22) bilayers as a function of the hydrophobicity of the molecules, (2) to prove the presence of a shorter and a longer limit ( n = 13 and 21) in the acyl chain length for the pressure-induced bilayer interdigitation and (3) to reveal the chain-length dependence of the thermodynamic quantities of the subtransitions including the volume change.

Dehydrins, which are group 2 late embryogenesis abundant (LEA) proteins, accumulate in plants during the development of the embryo and exposure to abiotic stresses including low temperature. Dehydrins exhibit cryoprotection of freezing-sensitive enzymes, e.g. lactate dehydrogenase (LDH). Although it has been reported that K-segments conserved in dehydrins are related to their cryoprotection activity, it has not been determined which sequence features of the K-segments contribute to the cryoprotection. A cryoprotection assay using LDH indicated that 13 K-segments including 12 K-segments found in Arabidopsis dehydrins and a typical K-segment (TypK, EKKGIMEKIKEKLPG) derived from the K-segments of many plants showed similar cryoprotective activities. Mutation of the TypK sequence demonstrated that hydrophobic amino acids were clearly involved in preventing the cryoinactivation, cryoaggregation, and cryodenaturation of LDH. We propose that the cryoprotective activities of dehydrins may be made possible by the hydrophobic residues of the K-segments.

An rf ion guide for mass separation of fission fragments has been developed as a new type of the ion-source of an ion guide isotope separator on-line (IGISOL). Fission fragments from an uranium target are thermalized in a large helium gas cell and extracted by a combination of dc and inhomogeneous rf electric fields. They are subsequently mass separated by an electromagnetic mass separator. Test experiments with a radioactive α-source and with fission fragments produced in the proton-induced fission of 238 U reveal that the yields of mass-separated radioactive ion beams are enhanced, due to the dc and rf electric fields in the gas cell.

To enhance the throughput of orthogonal frequency division multiple access (OFDMA) wireless local area network (WLAN) systems, this paper proposes a stations-clustering strategy in which stations in the basic service set (BSS) are grouped into clusters. In the proposed scheme, initially, to obtain statistics required for calculating the expected throughput achieved by OFDMA WLAN when the stations are grouped into a certain clustered-pattern, the access point (AP) and all stations belong to the same cluster and transmit DATA frames for a certain period. After that, the AP calculates the expected throughput for all clustered-patterns and chooses a clustered-pattern that maximizes the expected throughput. Then, the stations are grouped into clusters in accordance with the selected clustered-pattern, and the stations within the same cluster share the radio resource by OFDMA WLAN scheme. Numerical simulation confirms that the proposed scheme can maximize throughput performance by introduction of dynamic station clustering in the single BSS environment and it is also effective in preventing channel state information (CSI) feedback blocking due to station exposition in the overlapping BSS environment.

Solving the problem of plasma wall interaction is important for developing the fusion reactor. One of the problems involved with this interaction is plasma driven permeation (PDP), the phenomenon of large hydrogen permeation by plasma. This report focuses on previous studies of PDP, and reviews the abstracts of many experimental and theoretical works regarding PDP. In addition, this report introduces our original work on low temperature plasma driven permeation. In our work, ECR and RF heating plasma devices and various kinds of metal membranes were employed. Also researched were the dependencies of membrane thickness, temperature, and surface conditions on PDP. The incident hydrogen flux rate, which is little known in PDP experiments using a plasma discharging device, was estimated by calculating plasma composition. The mechanism of low temperature PDP was investigated and shown conceptually.

Kinect is a popular edition of depth sensor and is useful for realizing NUI in ubiquitous computing environment. This paper proposes a method for human face direction estimation based on the depth image from depth sensor. Our method works without using color information and is possible to work in dark environment and get better results than traditional methods. This paper describes the basic idea and basic design of our method.

Cathodes composed of layered transition metal oxides LiMO2 (M = Co, Ni) and spinel manganese oxide LiMn2O4, carbon anodes, and nonaqueous electrolyte solutions have been investigated with the aim of achieving higher energy density. The lithium-ion rechargeable cell using the LiCoO2 cathode and the propylene carbonate(PC)-diethyl carbonate (DEC)/ LiPF6 electrolyte solution exhibits excellent characteristics. Furthermore, non-graphitizable carbon such as polyfurfuryl alcohol derived carbon has larger capacity and better cycleability than graphitizable carbon such as coke.

Ammonia is one of the important toxins produced by Helicobacter pylori (H. pylori), the major cause of peptic ulcer diseases. We examined whether glutamine or marzulene (a gastroprotective drug containing 1% sodium azulene and 99% glutamine) protects the gastric mucosa against H. pylori in vivo and investigated the mechanism underlying glutamine-induced mucosal protection against ammonia in gastric epithelial cells in vitro. Mongolian gerbils were fed for 3 months with a diet containing glutamine (2% – 20%) or marzulene (20%) starting from 2 weeks or 2 years after H. pylori infection. Then, gastric mucosal changes were evaluated both macro- and microscopically. Cultured gastric epithelial cells were incubated in the presence of ammonia, with or without glutamine; and cell viability, ammonia accumulation, and chemokine production were determined. Gerbils exhibited edema, congestion, and erosion after 3-month infection; and after 2-year infection, they showed cancer-like changes in the gastric mucosa. Glutamine and marzulene significantly suppressed these pathological changes caused in the gastric mucosa by H. pylori infection. Ammonia was accumulated in the cells, resulting in an increase in chemokine production and a decrease in cell viability. These pathological responses were prevented by glutamine. In addition, glutamine decreased chemokine production and cell death through inhibition of cellular accumulation of ammonia, resulting in the prevention of H. pylori–induced gastric diseases in vivo. These results suggest that glutamine/marzulene would be useful for prophylactic treatment of H. pylori–induced gastric diseases in patients. Keywords:: glutamine, gastric mucosa, Helicobacter pylori, protection, cell death, gastrointestinal tract

We examined the influence of TRPA1 on the epithelial restitution using a rat gastric epithelial cell line RGM1 monolayer. RGM1 cells were inoculated in 24-well plates cultured for 24 hr, and then starved for 24 hr in a culture medium at 37 degrees C under 5 % CO(2) in air. After obtaining a confluent RGM1 cell monolayer, a round artificial wound of constant size was induced in the center of the cell monolayer using a pencil-type mixer with a rotating silicon tip. The repair process was monitored by quantitatively measuring the area of the epithelial wound (cell-free area). Immediately after the wound induction, cells at the edge of wound started to form lamellipodia, migrating toward the center of wound, and by so doing the cell-free area was decreased over time. The addition of icilin, the TRPA1 agonist, suppressed the recovery of the epithelial wound in a concentration-dependent manner. Likewise, another TRPA1 agonist, ally isothiocyanate, also significantly inhibited the wound repair. In addition, the recovery of the epithelial wound was potently inhibited when the ambient temperature was lowered to 17 degrees C, the threshold temperature where TRPA1 is known to be activated. By contrast, the wound healing was not affected by either menthol, the TRPM8 agonist, or capsaicin, the TRPV1 agonist. These results showed for the first time that the activation of TRPA1 inhibited the repair of the epithelial wound in the stomach, probably by the suppression of cell migration, and suggested the involvement of TRPA1 in the mechanism of gastric epithelial restitution.

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Background/Aim: Muscarinic acetylcholine receptors (mAChRs) consist of five subtypes (M1~M5) and are widely expressed to mediate diverse autonomic functions in peripheral organs, including the gastrointestinal tract. Although both M1and M3receptors reportedly play a role in the regulation of pepsin secretion in response to acetylcholine, we recently found that carbachol (CCh)-induced pepsin secretion wasmarkedly decreased inM4 knockout (KO) mice. In the present study, we demonstrated, using M1~M5 KO mice, the importance of M4 receptors in the cholinergic regulation of pepsin secretion and investigated how this secretion is modulated by the activation of M4 receptors. Methods: C57BL/6J mice of wildtype (WT) and M1-, M2-, M3-, M4or M5-KO were used. Under urethane anesthesia, the abdomen was incised, the cardiac portion was ligated, and an acute fistula prepared with a polyethylene tube was provided in the stomach through a pylorus. Then, the stomach was instilled with saline (0.4 ml) through the fistula, and the solution was changed every 20 min. CCh (30 μg/kg) was given SC as a single injection. Atropine (0.3 mg/kg) or CYN154806 [somatostatin-2 receptor (SST2R) antagonist 0.1-3mg/kg] was given SC 20 min before CCh. Expressions of D cells and M4 receptors were examined immunohistochemically by double staining with anti-somatostatin and anti-M4 receptor antibodies. Results: CCh caused an increase of pepsin secretion in WT mice, and the effect was completely inhibited by prior administration of atropine. The stimulatory effect of CCh was similarly observed in the animals lacking M1-, M2or M5-receptors but significantly decreased in M3or M4KO mice, as compared to WT; especially, the response was all but completely abolished in M4-KOmice. CYN154806, the SST2R antagonist, significantly reversed the decreased pepsin response to CCh in M4but not M3-KO mice. The M4-KO mice showed basal pepsin secretion much less than WT mice, and these changes were also reversed by CYN154806. By contrast, somatostatin decreased pepsin secretion under basal and CCh-stimulated conditions. Furthermore, the immunohistochemical study showed the localization ofM4 receptors on D cells in the mouse stomach. Conclusion: These results suggest that under cholinergic stimulation the secretion of pepsin is mediated mainly by the activation of M4-receptors and partly through M3-receptors but does not involve other muscarinic receptor subtypes. Somatostatin has an inhibitory effect on pepsin secretion through SST2 receptors. It is assumed that the activation of M4-receptors inhibits the release of somatostatin from D cells and results in enhancement of pepsin response.