Imaging of Accumulated Mechanical Stresses Using Self-Assembled Layered Conjugated Polymer.

When mechanical stresses, such as tensile, compressive, and frictional stresses, are applied to objects by various motions, they are accumulated in materials. Conventional mechanoresponsive materials and sensors detect one-time applied stress. However, the accumulated stresses are not visualized or measured in previous works. The present study demonstrated imaging and sensing of not only one-time but also accumulated tensile, compressive, and frictional stresses. Polyurethane (PU) film was combined with 2D layered polydiacetylene (PDA), a stimuli-responsive color-changing polymer. PDA generally exhibits no color changes with the application of tensile and compression stresses because the molecular motion leading to the color change is not induced by such mechanical stresses. Here the versatile mechanoresponsiveness was achieved using a block copolymer guest partially intercalated in the layered PDA. As the interlayer and outerlayer segments interact with PDA and PU, respectively, the applied stresses to the film are transferred from PU to PDA via the block copolymer guest. The color changes of the film imaged and quantified the accumulated work depending on the number and strength of the applied multiple stresses such as tensile, compressive, and frictional stresses. The design strategy of materials and methodology of sensing can be applied to the development of new sensors for accumulated mechanical stresses in a wide range of length and strength scales.

A Layered Polydiacetylene Containing Hydrogen-Bonding 4,4'-Bipyridyl Guests: Reversible Color Changes with a Wide-Range Temperature Response.

Invited for this month's cover is the group of Prof. Yuya Oaki, Keio University, Japan. The cover picture shows a layered polydiacetylene containing hydrogen-bonding 4,4'-bipyridyl guests formed through self-organization. In classical intercalation chemistry, the interlayer guests are intercalated in the host layers via rigid strong electrostatic interaction. The weaker interlayer interaction via hydrogen bond promotes the dynamic motion directing the thermoresponsive color changes in a wide temperature range. More information can be found in the Full Paper by Yuya Oaki, and co-workers.

A Layered Polydiacetylene Containing Hydrogen-Bonding 4,4'-Bipyridyl Guests: Reversible Color Changes with a Wide-Range Temperature Response.

Layered organic polymers have intercalation capabilities and dynamic properties. In classical intercalation chemistry, the interlayer guests are intercalated in the host layers via electrostatic interaction. The present work shows the organic layered materials with the host-guest interlayer interaction via hydrogen bond. Polydiacetylene (PDA) exhibits color changes from blue to red with the application of external stimuli, such as thermal and mechanical stresses. Here we report on a layered PDA containing 4,4'-bipyridyl in the interlayer space as a hydrogen-bonding guest. Whereas the layered PDA without interlayer guest shows the color transition at 65 °C, gradual color changes with two-stage reversibility are observed in the temperature range of -20-240 °C by the introduction of the hydrogen-bonding guest. The weaker interlayer interaction via the hydrogen bond promotes the dynamic motion directing the thermoresponsive color changes in a wide temperature range.

Spiral drawing: Quantitative analysis and artificial-intelligence-based diagnosis using a smartphone.

BACKGROUND: The evaluation of neurological examination in clinical practice still remains qualitative or semi-quantitative, and the results often vary depending on an examiner's skill level and are less objective. In this study, we developed a smartphone-based application to investigate quantifying neurological examinations using hand-drawn spirals and diagnose patients with tremor using artificial intelligence (AI). METHODS: This study included 24 and 26 patients with essential tremor (ET) and cerebellar disease (CD), respectively, and 41 age-matched normal controls (NCs). We obtained 69, 46, and 56 hand-drawn spirals from the NC, ET, and CD groups, respectively, as image data captured by smartphones. The patients traced a printed reference spiral. The length of this spiral was compared with the reference spiral length (% of spiral length) and the total deviation area between these spirals was calculated. The server also estimates the diagnostic probability through AI. RESULTS: The quantified spiral analysis (% of spiral length and deviation area) significantly correlated with disease severity in each disease group, and significant differences in the deviation area were observed among all groups. The AI diagnosis showed 79%, 70%, and 73% accuracies for the NC, ET, and CD groups, respectively. CONCLUSION: This study indicates the possibility of using a smartphone as a medical examination tool and demonstrates the application of AI in neurological examinations.

Gaussian mixture model for coarse-grained modeling from XFEL.

We explore the advantage of Gaussian mixture model (GMM) for interpretation of single particle diffraction patterns from X-ray free electron laser (XFEL) experiments. GMM approximates a biomolecular shape by the superposition of Gaussian distributions. As the Fourier transformation of GMM can be quickly performed, we can efficiently simulate XFEL diffraction patterns from approximated structure models. We report that the resolution that GMM can accurately reproduce is proportional to the cubic root of the number of Gaussians used in the modeling. This behavior can be attributed to the correspondence between the number of adjustable parameters in GMM and the amount of sampling points in diffraction space. Furthermore, GMMs can successfully be used to perform angular assignment and to detect conformational variation. These results demonstrate that GMMs serve as useful coarse-grained models for hybrid approach in XFEL single particle experiments.

Anti-survivin single-domain antibodies derived from an artificial library including three synthetic random regions by in vitro selection using cDNA display.

Single-domain antibodies (variable domain of the heavy chain of a heavy chain antibody; VHH) are promising reagents for therapeutics and diagnostics because of their stability, cost-effective production and material workability as a small antibody. Currently, general acquisition of a VHH using immunization of camelids is inconvenient from the standpoint of animal protection, cost and the process is time-consuming. Thus, a straightforward and efficient method for screening VHHs against a target molecule is required. In this study, we examined whether in vitro selection of a VHH against a target protein could be performed by a cDNA display method with an artificial VHH library that had the three complementarity-determining regions (CDRs) randomized by chemical synthesis. The results revealed that a particular VHH against survivin, which is a member of the inhibitor of apoptosis family, was selected with affinity in the range of 10-7 to 10-8 M. The in vitro selection of a VHH using cDNA display with an artificial synthesized library without animal immunization was shown to be effective for rapid and inexpensive screening of VHHs against a target protein.

α-Catenin Controls the Anisotropy of Force Distribution at Cell-Cell Junctions during Collective Cell Migration.

Adherens junctions (AJs) control epithelial cell behavior, such as collective movement and morphological changes, during development and in disease. However, the molecular mechanism of AJ remodeling remains incompletely understood. Here, we report that the conformational activation of α-catenin is the key event in the dynamic regulation of AJ remodeling. α-catenin activates RhoA to increase actomyosin contractility at cell-cell junctions. This leads to the stabilization of activated α-catenin, in part through the recruitment of the actin-binding proteins, vinculin and afadin. In this way, α-catenin regulates force sensing, as well as force transmission, through a Rho-mediated feedback mechanism. We further show that this is important for stable directional alignment of multiple cells during collective cell movement by both experimental observation and mathematical modeling. Taken together, our findings demonstrate that α-catenin controls the establishment of anisotropic force distribution at cell junctions to enable cooperative movement of the epithelial cell sheet.

Protective effects against tumors and infection by interleukin-27 through promotion of expansion and differentiation of hematopoietic stem cells into myeloid progenitors.

Interleukin (IL)-27 is a multifunctional cytokine that belongs to the IL-6/IL-12 family and has potent antitumor activity through various mechanisms. Our novel findings indicate that IL-27 directly acts on hematopoietic stem cells and promotes their expansion and differentiation into myeloid progenitors to control infection and to eradicate tumors.

Predatory publishing and cybercrime targeting academics.

The purpose of this report is to inform and warn academics about practices used by cybercriminals who seek to profit from unwary scholars and undermine the industry of science. This report describes the signs, symptoms, characteristics, and consequences of predatory publishing and related forms of consumer fraud. Methods to curb these cybercrimes include educating scholars and students about tactics used by predatory publishers; institutional changes in how faculty are evaluated using publications; soliciting cooperation from the industries that support academic publishing and indexing to curb incorporation of illegitimate journals; and taking an offensive position by reporting these consumer fraud crimes to the authorities. Over and above the problem of publishing good science in fraudulent journals, disseminating and citing poor-quality research threaten the credibility of science and of nursing.

Evaluating cultural competence among Japanese clinical nurses: Analyses of a translated scale.

This paper describes the factor analysis testing and construct validation of the Japanese version of the Caffrey Cultural Competence Health Services (J-CCCHS). The inventory, composed of 28 items, was translated using language and subject matter experts. Psychometric testing (exploratory factor, alpha reliability, and confirmatory factor analyses) was undertaken with nurses (N = 7494, 92% female, mean age 32.6 years) from 19 hospitals across Japan. Principal components extraction with varimax rotation yielded a 5-factor solution (62.31% variance explained) that was labeled: knowledge, comfort-proximal, comfort-distal, awareness, and awareness of national policy. Cronbach α for the subscales ranged from 0.756 to 0.892. In confirmatory factor analysis using the robust maximum likelihood estimator, the chi-square test was as follows: χ2 (340) = 14604.44, P < .001. After correlated errors were introduced, there was evidence of improved model fit (χ2 (335) = 8681.61, P < .05) but the other indices showed improvement (RMSEA = .058 [90% CI, 0.057-0.059], TLI = .891, CFI = .903, and SRMR = .059). The discriminating power of the J-CCCHS was indicated by statistically mean differences in J-CCCHS subscale scores between predefined groups. Taking into consideration that this is the first foray into construct validation for this instrument, and that fit was improved when a subsequent data driven model was tested, and it has the ability to distinguish between known groups that are expected to differ in cultural competence, the instrument can be of value to clinicians and educators alike.

Cultural characteristics of nursing practice in Japan.

The population of Japan has become multi-cultural, and there is more demand for culturally competent nursing care. The purpose of this study was to explore cultural characteristics of nursing practice in Japan focusing on behaviour. We interviewed 25 professionals with experience in or knowledge of nursing practice both in Japan and either the United States, the United Kingdom, Sweden, Thailand or South Korea. Qualitative content analysis has yielded three themes for cultural characteristics of nursing practice in Japan: practice expectations, communication and relationships with patients. Practice expectations for nurses in Japan involved various aspects; nurses conducted a wide range of basic nursing tasks, including bed baths and toileting. They often relied on non-verbal communication to deliver thoughtfulness and perceptiveness. They typically show deference to doctors and colleagues, emphasizing building and maintaining harmony with them. This emphasis on a multifaceted, non-verbal, and harmonious approach seemed characteristic of practice among Japanese nurses.

A RhoA and Rnd3 cycle regulates actin reassembly during membrane blebbing.

The actin cytoskeleton usually lies beneath the plasma membrane. When the membrane-associated actin cytoskeleton is transiently disrupted or the intracellular pressure is increased, the plasma membrane detaches from the cortex and protrudes. Such protruded membrane regions are called blebs. However, the molecular mechanisms underlying membrane blebbing are poorly understood. This study revealed that epidermal growth factor receptor kinase substrate 8 (Eps8) and ezrin are important regulators of rapid actin reassembly for the initiation and retraction of protruded blebs. Live-cell imaging of membrane blebbing revealed that local reassembly of actin filaments occurred at Eps8- and activated ezrin-positive foci of membrane blebs. Furthermore, we found that a RhoA-ROCK-Rnd3 feedback loop determined the local reassembly sites of the actin cortex during membrane blebbing.

A versatile puromycin-linker using cnvK for high-throughput in vitro selection by cDNA display.

cDNA display is a powerful in vitro display technology used to explore functional peptides and proteins from a huge library by in vitro selection. In addition to expediting the in vitro selection cycle by using cDNA display, easy and rapid functional analysis of selected candidate clones is crucial for high-throughput screening of functional peptides and proteins. In this report, a versatile puromycin-linker employing an ultrafast photo-cross-linker, 3-cyanovinylcarbazole nucleoside, is introduced. Its utility for both in vitro selection using cDNA display and protein-protein interaction analysis using a surface plasmon resonance (SPR) system is described. Using this versatile puromycin-linker, we demonstrated the model in vitro selection of the FLAG epitope and a SPR-based assay to measure the dissociation constant between the B domain of protein A and immunoglobulin G. Improvement of the puromycin-linker as described herein should make the cDNA display method easier to utilize for design of protein or peptide based affinity reagents.

Easy and rapid binding assay for functional analysis of disulfide-containing peptides by a pull-down method using a puromycin-linker and a cell-free translation system.

Constrained peptides are an attractive class as affinity reagents or drug leads owing to their excellent binding properties. Many kinds of these peptides, such as cyclic peptides containing disulfide bridges, are found in nature or designed artificially by directed evolution. However, confirming the binding properties of the disulfide-rich peptides can be generally difficult, because of oxidative folding problems in the preparation steps. Therefore, a method for evaluating the binding properties of such peptides rapidly and easily is required. Here, we report an easy and rapid method for preparing biotin-attached peptides containing disulfide bridges or a chemical cross-linker using a cell-free translation system and a puromycin-linker, which is applicable to pull-down assays for protein (or peptide) molecular interaction analysis.

Amino group binding peptide aptamers with double disulphide-bridged loops selected by in vitro selection using cDNA display.

Peptide aptamers that specifically bind to the amino group on a solid-phase were screened by in vitro selection using the cDNA display method. The identified peptides have a unique structure containing two cyclic loops with disulphide bonds and a linkage region, which were indispensable for molecular recognition.

Increasing the library size in cDNA display by optimizing purification procedures.

BACKGROUND: The library size is critical for selection in evolutionary molecular engineering (directed evolution). Although cDNA display has become a promising in vitro display technology by overcoming the instability of mRNA display, it is hindered by low yields. In this study, we improved the yield of cDNA display molecules by carefully examining each step of the preparation process. FINDINGS: We found that steric hindrance of ribosomes binding to the mRNA-protein fusion molecules was interfering with biotin-streptavidin binding. Additionally, reducing buffer exchange by performing RNase digestion in the His-tag-binding buffer to release the cDNA display molecules improved their His-tag purification. CONCLUSION: Our optimized conditions have improved the yield of cDNA display molecules by more than 10 times over currently used methods, making cDNA display more practically available in evolutionary molecular engineering.

A pull-down method with a biotinylated bait protein prepared by cell-free translation using a puromycin linker.

In this paper, we demonstrate a novel pull-down method that dramatically reduces the cost and preparation time of a bait protein by cell-free translation with a puromycin linker. With the C-terminus of the bait protein linked to biotin through a puromycin molecule after the translation reaction and subsequent mRNA degradation by RNase, the prey protein was easily pulled down by streptavidin-coated magnetic beads in a test tube. Three fluorescent prey protein types were tested and confirmed by gel electrophoresis to be pulled down easily and rapidly, depending on their affinity.

The Asian Research & Collaboration Center for Nursing & Cultural Studies in Japan.

The purpose of this paper is to describe current cultural issues in Japanese health-care services that have resulted from the increased immigration. Also described is the establishment of a new academic research centre that will focus on culturally appropriate nursing care. There are many health-care issues in Japan caused by a shortage of health-care workers and disparities in access to health care. The major issues are an increase in the number of foreign patients, foreign nurses and care workers. Despite the occurrence of similar issues in other countries, Japan's situation and the causes are different. In response to dynamic demographic and health-care changes in Japan, we launched the Asian Research & Collaboration Center for Nursing & Cultural Studies at Chiba University Graduate School of Nursing.

Evolution of disulfide-rich peptide aptamers using cDNA display.

Protein scaffolds containing some disulfide bonds (e.g., Knottin, Kunitz domain, etc.) are promising candidates for molecular recognition. cDNA display has been developed to screen functional disulfide-rich peptide aptamers from a vast library by promoting disulfide bond shuffling after the synthesis of peptides in a cell-free translation system. Here we present a detailed protocol for the selection of disulfide-rich peptide aptamers against interleukin 6 receptor (IL-6R) from a 35-amino acid peptide library containing 32 amino acids in the random region, which is linked to its genotype by cDNA display.

One-pot preparation of mRNA/cDNA display by a novel and versatile puromycin-linker DNA.

A rapid, easy, and robust preparation method for mRNA/cDNA display using a newly designed puromycin-linker DNA is presented. The new linker is structurally simple, easy to synthesize, and cost-effective for use in "in vitro peptide and protein selection". An introduction of RNase T1 nuclease site to the new linker facilitates the easy recovery of mRNA/cDNA displayed protein by an improvement of the efficiency of ligating the linker to mRNAs and efficient release of mRNA/cDNA displayed protein from the solid-phase (magnetic bead). For application demonstration, affinity selections were successfully performed. Furthermore, we introduced a "one-pot" preparation protocol to perform mRNA display easy. Unlike conventional approaches that require tedious and downstream multistep process including purification, this protocol will make the mRNA/cDNA display methods more practical and convenient and also facilitate the development of next-generation, high-throughput mRNA/cDNA display systems amenable to automation.