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The pairing of 1,3-di-tert-butylimidazol-2-ylidene (NHCtBu) and methylaluminum bis(2,6-di-tert-butyl-4-methylphenoxide) (MAD) acted as an interacting Lewis pair (ILP) for anionic polymerization of several acrylates.

Cage-like supramolecular assemblies called molecular cages, which possess attractive functions, have been prepared. Although biomolecule-based nanocages are required for biological/medical applications such as drug delivery systems, the majority of nanocages are constructed using aromatic compounds with lower biocompatibility and biodegradability. In this study, the construction of a peptide nanocage consisting of an oligoproline conjugate is demonstrated. The conjugate was easy to prepare and had high biocompatibility. The oligoproline moiety of the conjugate had a rigid, rod-like structure suitable for the backbone of the supramolecular nanocage. The conjugates self-assembled to form peptide nanocages with a huge inner cavity.

The N-heterocyclic carbene 1,3-di-tert-butylimidazol-2-ylidene (NHCtBu) and its 1:1 adduct with methyl sorbate (MS) were found to initiate anionic polymerization of N-substituted maleimides (RMIs) in organic solvents at −20 °C to afford linear and cyclic poly(RMI)s, respectively. Quantitative monomer consumption was observed when a bulky aluminum Lewis acid, such as methylaluminum bis(2,6-di-tert-butyl-4-methylphenoxide) (MAD), was used as an additive. In the presence of the NHCtBu:MS adduct as an initiator, monomer consumption was followed by ring closure without the need for highly diluted conditions to give cyclic poly(RMI)s containing α-terminal MS units, which exhibited an Mn of 3.4 × 103–6.2 × 103 and a broad polydispersity index (Mw/Mn = 2.43–2.65). Dilution was not required due to the presence of an α-terminal NHCtBu group, which acted as a counter cation for the propagating center during polymerization. The broad molecular weight distributions of the obtained polymers were ascribed to a chain transfer upon abstraction of the α-carbonyl proton of the RMIs, particularly to the neighboring NHCtBu cation unit. 1H NMR and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass analyses indicated that the proton transfer of the acidic proton was induced by the propagating anion. The topologies of the linear and cyclic poly(RMI)s were directly observed by transmission electron microscopy (TEM). Direct Observation of Cyclic Poly(N-substituted maleimide)s with Broad Size Distributions Synthesized by Anionic Polymerization using an N-Heterocyclic Carbene and Successive Ring Closure Without High Dilutions.

To conduct an appropriate medical interview, education and clinical experience are necessary. The usefulness of computer-based medical diagnostic support systems has been reported in medical interviewing. However, only a few reports have actually applied these systems and noted changes in the quality of the medical interview of residents. We aimed to examine how the use of a medical interview support application changes the medical interviews of residents. The study was conducted on 15 residents (with less than two years post-graduation) and ran from November 2020 to March 2021. Faculty members played the role of simulated patients in 20 cases, and the residents conducted the medical interviews. In 10 of the 20 cases, a medical interview support application was used. After the interview, the residents were asked to list up to 10 differential diseases; the interview was considered appropriate if it included the disease portrayed by the simulated patient. Furthermore, the duration of the medical interview, the number of questions asked, and changes in stress parameters were evaluated. The use of a medical interview support application increased the percentage of appropriate medical interviews. Considering the frequency, the use of a medical interview support application increased the rate of appropriate medical interviews in the rare disease group, as well as the number of questions and duration of the interviews. No stress reduction was observed. The medical interview support application may be a useful tool in identifying appropriate differential diseases during medical interviews by residents.

BackgroundDelirium has been shown to prolong the length of intensive care unit stay, hospitalization, and duration of ventilatory control, in addition to increasing the use of sedatives and increasing the medical costs. Although there have been a number of reports referring to risk factors for the development of delirium, no model has been developed to predict delirium in trauma patients at the time of admission. This study aimed to create a scoring system that predicts delirium in trauma patients.MethodsIn this single-center, retrospective, observational study, trauma patients aged 18 years and older requiring hospitalization more than 48 hours were included and divided into the development and validation cohorts. Univariate analysis was performed in the development cohort to identify factors significantly associated with prediction of delirium. The final scoring system for predicting delirium was developed using multivariate analysis and internal validation was performed.ResultsOf the 308 patients in the development cohort, 91 developed delirium. Clinical Frailty Score, fibrin/fibrinogen degradation products, low body mass index, lactate level, and Glasgow Coma Scale score were independently associated with the development of delirium. We developed a scoring system using these factors and calculated the delirium predictive score, which had an area under the curve of 0.85. In the validation cohort, 46 of 206 patients developed delirium. The area under the curve for the validation cohort was 0.86, and the calibration plot analysis revealed the scoring system was well calibrated in the validation cohort.DiscussionThis scoring system for predicting delirium in trauma patients consists of only five risk factors. Delirium prediction at the time of admission may be useful in clinical practice.Level of evidencePrognostic and epidemiological, level III.

Self-organization based on specific interactions has been actively studied for the formation of highly ordered and hierarchical structures on the molecular scale. We designed and synthesized a nucleopeptide, Ac-VEVS(g(GC)3)(VE)7-CONH2, having a nucleotide graft-chain in a peptide main-chain, and a spacer peptide acting as a template for ferric oxide mineralization. The synthesized nucleopeptide and spacer peptide mixture formed a self-organized assembly having a nanospace owing to the complementary base pairing between the nucleotide graft-chains of the nucleopeptides and intermolecular hydrogen-bonding between the peptide chains on the substrates. In this study, we report the selective mineralization of magnetite in the nanospace which acted as a reaction field. Mineralized magnetite formed an oriented nano-tape, whose morphology was similar to that of the template nanosheet. This implies that the nanospace in the ordered nanosheet formed by self-organization processes of the nucleopeptide and spacer peptide is extremely useful as a reaction field for the mineralization of structure-controlled magnetite.

Background Medical interviews play an important role in disease diagnosis. Medical interview education and clinical experience are required to perform an appropriate medical interview; however, not all medical staff can perform medical interviews at the same level. This study examined whether a medical interview support application could enable physicians with little clinical experience to perform highly accurate medical interviews. Methods Fifteen junior residents (less than two years of post-graduation) performed medical interviews with 20 cases portrayed by simulated patients. In 10 cases, a medical interview support application was used. After the medical interview, the participants were asked to list about 10 differential diagnoses. The interview was considered appropriate if it included the disease portrayed by the simulated patient. Results The use of a medical interview support application increased the percentage of appropriate medical interviews. Considering the frequency, the use of a medical interview support application increased the rate of appropriate medical interviews in the rare disease group. It also increased the number of questions and the duration of the interview. No stress-reduction was observed. Conclusion The medical interview application may be a useful tool in identifying appropriate differential diseases.

We designed and synthesized amphiphilic glycopeptides with glucose or galactose at the C-terminals. We observed the protein-induced structural changes of the amphiphilic glycopeptide assembly in the lipid bilayer membrane using transmission electron microscopy (TEM) and Fourier transform infrared reflection-absorption spectra (FTIR-RAS) measurements. The glycopeptides re-arranged to form a bundle that acted as an ion channel due to the interaction among the target protein and the terminal sugar groups of the glycopeptides. The bundle in the lipid bilayer membrane was fixed on a gold-deposited quartz crystal microbalance (QCM) electrode by the membrane fusion method. The protein-induced re-arrangement of the terminal sugar groups formed a binding site that acted as a receptor, and the re-binding of the target protein to the binding site induced the closing of the channel. We monitored the detection of target proteins by the changes of the electrochemical properties of the membrane. The response current of the membrane induced by the target protein recognition was expressed by an equivalent circuit consisting of resistors and capacitors when a triangular voltage was applied. We used peanut lectin (PNA) and concanavalin A (ConA) as target proteins. The sensing membrane induced by PNA shows the specific response to PNA, and the ConA-induced membrane responded selectively to ConA. Furthermore, PNA-induced sensing membranes showed relatively low recognition ability for lectin from Ricinus Agglutinin (RCA120) and mushroom lectin (ABA), which have galactose binding sites. The protein-induced self-organization formed the spatial arrangement of the sugar chains specific to the binding site of the target protein. These findings demonstrate the possibility of fabricating a sensing device with multi-recognition ability that can recognize proteins even if the structure is unknown, by the protein-induced self-organization process.

Tumor growth is closely related to the development of an intrinsic vascular network. However, microvascular appearance was not regarding highly to pathological diagnosis, though clinical applicability of endoscopic narrow-bad imaging (NBI) is developed in the oral cavity. To analyze changes of intraepithelial papillary capillary loop (IPCLs) patterns as the utility for pathological diagnosis, comparative histomorphometric analysis of IPCLs among squamous cell hyperplasia, leukoplakia with low- or high-grade dysplasia, and oral squamous cell carcinoma (OSCC) had performed. Subjects were 40 clinically hyperkeratosis, histologically consisted 5 groups; each 10 of squamous cell hyperplasia, low- or high-grade dysplasia, OSCC and normal mucosae. Sections with smooth muscle actin and CD34 immunoreactivities were used to examine comparative histomorphometric analysis on the basis of IPCL irregularities. The area, shortest diameter, proximity to the basement membrane and circularity were measured using Win Roof image analysis software. Statistical analyses were done by Kruskal–Wallis and Steel–Dwass tests. Values of p

In order to measure friction coefficients of tire grounding surfaces in car running, a simple cantilever-type tactile sensor that can detect the vertical load and friction force applied to the sensing part as well as direction of the friction force, simultaneously, has been proposed. The present study equips the proposed sensor to a tire and confirms that the sensor can measure the friction coefficient of the tire grounding surface. For this purpose, measurements in this study were conducted using a sensor under a similar load as that of a common automobile travelling in an arbitrary direction. In order to perform the experiments under a high load in an arbitrary direction, we developed a parallel mechanism-type tire-driving device. The developed device can apply a high load to the tire in an arbitrary direction and can measure the vertical load, friction force, and the direction of the friction force applied to the tire involving the sensor. Thus, the measurement accuracy of the proposed sensor can be verified by comparing the output of the sensor to that of the driving device. As a result of this study, we clarified that the measurement values of the sensor are affected by the deformation of the tire, and proposed a method for correcting the effect of the tire deformation. By introducing the proposed correction method to the measurement of the sensor, it was confirmed that the friction coefficients of various surfaces can be measured with sufficient accuracy under a practical high-load condition.

Electrophoretic deposition (EPD) is one of the most important coating methods. This method has various advantages, such as being able to make a coating as a uniform film, even on a complex surface. Recently, we found that non-ionic poly(ester-sulfone) materials show anode selective electrophoretic behavior. In this paper, we performed electrophoresis of non-ionic nano particles (diameter: ca. 300 nm), prepared via soap-free emulsion copolymerization of vinyl monomers containing a sulfide linkage with styrene and subsequent oxidation to a sulfonyl group. After EPD, a structural color was observed, indicating that the monodisperse spheres had attached to the surface and exhibited specific light diffraction, in which the wavenumber is dependent on the incident angle.

We propose a method for self-bonding between electrodes using the self-organizational processes of a silica-coated peptide hybrid nanowire. We designed and synthesized a 23-mer α-helical peptide having functional sites that serve as catalytic sites for silica mineralization (glutamic acid [Glu] and lysine [Lys]) and binding (serine [Ser]), as well as for the formation of a Co(II) ion complex. The peptides formed nanowires composed of α-helical bundles that showed axial connection because of complexation between Co(II) and the histidine (His) residues, and macro-dipole interactions of the α-helical peptides. The nanowires self-bonded between the electrodes, and the surface of the nanowires was coated with silica using mineralization. The silica coating of the surface of the Co(II)-coordinated peptide nanowires induced two kinds of phenomena: (1) structural stabilization of the peptide nanowire component in the composite and (2) an increase in conductivity compared with that of the non-coated peptide nanowires.

Crystal phase and morphology of biominerals may be precisely regulated by controlled nucleation and selective crystal growth through biomineralization on organic templates such as a protein. We herein propose new control factors of selective crystal growth by the biomineralization process. In this study, a designed β-sheet Ac-VHVEVS-CONH2 peptide was used as a multifunctional template that acted as mineral source supplier and having crystal phase control ability of calcium carbonate (CaCO3) during a self-supplied mineralization. The peptides formed three-dimensional nanofiber networks composed of assembled bilayer β-sheets. The assembly hydrolyzed urea molecules to one carbonate anion and two ammonium cations owing to a charge relay effect between His and Ser residues under mild conditions. CaCO3 was selectively mineralized on the peptide assembly using the generated carbonate anions on the template. Morphology of the obtained CaCO3 was fiber-like structure, similar to that of the peptide template. The mineralized CaCO3 on the peptide template had aragonite phase. This implies that CaCO3 nuclei, generated using the carbonate anions produced by the hydrolysis of urea on the surface of the peptide assembly, preferentially grew into aragonite phase, the growth axis of which aligned parallel to the direction of the β-sheet fiber axis.

We recently reported on newly synthesized S-galactosyl oligo(Arg) conjugates to overcome the serious problem of the passage through the E. coli cell membrane. Following in vivo expression of green fluorescent protein (GFP) induced by each of the S-galactosyl (Arg)n constructs (n = 5, 6, 8) at the T5 promoter in E. coli for 18 h, we visually observed that the cultures fluoresced green light when excited with UV light. The fluorescence intensities for these cultures were greater than that found for a control culture, indicating that the peptides had induced GFP expression. In order to accomplish higher expression efficiency, we investigated the cluster effect and structural fine-tuning of new poly(2-oxazoline) containing CysArgArg as the cell-penetrating peptide (CPP) and S-galactosides when acting as inducers of recombinant protein expression under the control of lac operator/repressor systems in this article. Quantitative fluorescence intensities (calculated per molecule) also supported the observations that the cell-penetrating glyco poly(2-oxazoline)s were better inducers of GFP expression than glyco poly(2-oxazoline) containing no CPP or isopropyl β-d-thiogalactoside. Because the level of GFP expression was directly related to the number of sugar residues in each glyco poly(2-oxazoline), we propose that a cluster effect of the S-galactosides attached to the cell-penetrating poly(2-oxazoline) is responsible for how well the galactosides inhibited the lac repressor to activate the protein expression under the control of the lac operator/repressor system. A similar tendency was observed when the T7 promoter was placed upstream of the gene for an artificial extracellular matrix protein and glyco poly(2-oxazoline)s-CPP conjugates were used as inducers. To assess how the glyco poly(2-oxazoline) penetrate the cell membrane, we labeled the glyco poly(2-oxazoline) using 1-amino pyrene and directly observed the penetration process. Furthermore, we could visualize protein expression under the control of a lac promoter/operator/repressor system using transmission electron microscopy combined with energy dispersive X-ray analysis mapping.

Myositis ossificans (MO) is an extraskeletal tumor-like lesion with bone formation, and is relatively rare in the head and neck region. We report herein a clinicopathological analysis of MO associated with a muscle of mastication. The patient was a 70-year-old Japanese woman who presented with a tumorous mass in the right parotid area and no history of trauma. The surgically excised tumorous lesion consisted of proliferating fibroblastic cells with no atypia in the central portion, and a formation of trabecular osteoid and/or bony tissue in the peripheral portion as the so-called “zonal phenomenon”. The final histological diagnosis was MO, and the lesion was located in the posterior belly of the digastric muscle on computer tomography. A review of the literature showed that many cases of MO predominantly affected the medial pterygoid and masseter muscle and showed a history of previous trauma. The present case represents a rare case of nontraumatic MO in the uncommon location of the posterior belly of the digastric muscle.