Water-Mediated on-Demand Detachable Solid-State Adhesive of Porous Hydroxyapatite for Internal Organ Retractions.

Novel adhesives for biological tissues offer an advanced surgical approach. Here, we report the development and application of solid-state adhesives consisting of porous hydroxyapatite (HAp) biocompatible ceramics as novel internal organ retractors. The operational principles of the porous solid-state adhesives were experimentally established in terms of water migration from biological soft tissues into the pores of the adhesives, and their performance was evaluated on several soft tissues with different hydration states. As an example of practical medical utility, HAp adhesive devices demonstrated the holding ability of porcine livers and on-demand detachability in vivo, showing great potential as internal organ retractors in laparoscopic surgery. This article is protected by copyright. All rights reserved.

Improvement of cell growth in green algae Chlamydomonas reinhardtii through co-cultivation with yeast Saccharomyces cerevisiae.

PURPOSE: CO2 fixation methods using green algae have attracted considerable attention because they can be applied for the fixation of dilute CO2 in the atmosphere. However, green algae generally exhibit low CO2 fixation efficiency under atmospheric conditions. Therefore, it is a challenge to improve the CO2 fixation efficiency of green algae under atmospheric conditions. Co-cultivation of certain microalgae with heterotrophic microorganisms can increase the growth potential of microalgae under atmospheric conditions. The objective of this study was to determine the culture conditions under which the growth potential of green algae Chlamydomonas reinhardtii is enhanced by co-culturing with the yeast Saccharomyces cerevisiae, and to identify the cause of the enhanced growth potential. RESULTS: When C. reinhardtii and S. cerevisiae were co-cultured with an initial green algae to yeast inoculum ratio of 1:3, the cell concentration of C. reinhardtii reached 133 × 105 cells/mL on day 18 of culture, which was 1.5 times higher than that of the monoculture. Transcriptome analysis revealed that the expression levels of 363 green algae and 815 yeast genes were altered through co-cultivation. These included genes responsible for ammonium transport and CO2 enrichment mechanism in green algae and the genes responsible for glycolysis and stress responses in yeast. CONCLUSION: We successfully increased C. reinhardtii growth potential by co-culturing it with S. cerevisiae. The main reasons for this are likely to be an increase in inorganic nitrogen available to green algae via yeast metabolism and an increase in energy available for green algae growth instead of CO2 enrichment.

Noise Pareidolia Test in Parkinson's Disease and Atypical Parkinsonian Syndromes: A Retrospective Study.

INTRODUCTION: Pareidolias, or visual misperceptions, are a non-motor symptom of Parkinson's disease (PD) with unclear pathophysiology. The noise pareidolia test (NPT) is a tool for screening pareidolias. The usefulness of the NPT in differentiating PD from atypical parkinsonian syndromes (APS) is also unknown. METHODS: We retrospectively investigated 74 patients with PD and 18 patients with APS who took the NPT. Correlations between the number of pareidolic responses, gray matter volume, and cerebral blood flow were also examined in the patients with PD. RESULTS: The median number of pareidolic responses in patients with PD and patients with APS was 0 (interquartile range (IQR): 0-3) and 0 (IQR: 0-1), respectively, and tended to be higher in patients with PD than in those with APS (p = 0.077). It was significantly higher in patients with PD who had hallucinations (2; IQR: 0-9) (p = 0.016). The area under the receiver operating characteristic curve for the number of pareidolic responses in the NPT was 0.62 when used to differentiate PD and APS, and the optimal cutoff number of pareidolic responses was 2/3. Sensitivity and specificity were 25.7% and 100%, respectively. In the PD group, the number of pareidolic responses was correlated with age (r = 0.27; p = 0.021) and the Frontal Assessment Battery (FAB) score (r = -0.34; p = 0.0099). Magnetic resonance imaging showed no significant correlation between the number of pareidolic responses and the volume of focal gray matter. On cerebral hypoperfusion mapping, the left parietal lobe had a significant correlation with the number of pareidolic responses (r = 0.35; p = 0.027). CONCLUSION: The number of pareidolic responses in NPT was suggested to be useful as a red flag to rule out APS in differentiating PD from APS. In PD without dementia, the number of pareidolic responses was associated with reduced blood flow in the left parietal lobe.

Lipids and Minerals, Interplay in Biomineralization: Nature's Alchemy.

The main focus of this article is the role of lipids in biomineralization. Much of the discussion on biomineralization focuses on proteins in these decades. Indeed, collagen and acidic noncollagenous proteins effectively serve as templates for mineralization. However, other macromolecules such as lipids and polysaccharides have received less attention despite their abundance at mineralization sites. The matrix vesicle (MV) theory is widely accepted as the induction of early mineralization. Although ion concentration within the vesicles has been discussed in the initial mineralization in this theory, the role of phospholipids that constitute the vesicle membrane has not been discussed much. Comprehensive considerations, including pathological mineralization, exist regardless of the localization of MVs, the involvement of bacteria in dental calculus formation, and biomineralization caused by marine organisms such as corals, suggesting that initial mineralization found in these biological conditions might be a common reaction relating to lipids. In contrast, despite the abundance of lipids, mineralization occurs only in the limited tissue within our body. In other words, gathering knowledge and creating a path to understanding about lipid-based mineralization is extremely important in proposing new bone disease treatment methods. This article describes how lipids influence nucleation, mineralization, and expansion during hard tissue formation.

The association between exposure to hate speech or perceived discrimination and mental health problems among Korean residents in Japan.

This study evaluated the effect of perceived discrimination and racism on the mental health state of Korean residents in Japan, with a particular focus on the risk of post-traumatic stress disorder (PTSD), depression, and psychological distress. Surveys were sent to Korean residents in Japan and a total of 240 valid responses were received. The valid response rate was 27.1%. The participants answered several questionnaire items, including demographic information and questions pertaining to their experiences of perceived discrimination, along with three self-reported measures of mental health, i.e., the Japanese version of Impact of Event Scale-Revised, the Zung Self-rating Depression Scale (SDS), and the 12-item General Health Questionnaire (GHQ-12). The results indicated that Korean residents in Japan experience hate speech and discrimination with a markedly high frequency (92.9% and 100%, respectively), and that factors such as employment discrimination and exposure to hate speech via social networking services were significant predictors of probable PTSD and psychological distress.

The relationship between the initial pH and neurological outcome in patients with out-of-hospital cardiac arrest is affected by the status of recovery of spontaneous circulation on hospital arrival.

The early prediction of neurological outcomes is useful for out-of-hospital cardiac arrest (OHCA). The initial pH was associated with neurological outcomes, but the values varied among the studies. Patients admitted to our division with OHCA of cardiac origin between January 2015 and December 2022 were retrospectively examined (N = 199). A good neurological outcome was defined as a Glasgow-Pittsburgh cerebral performance category (CPC) of 1-2 at discharge. Patients were divided according to the achievement of recovery of spontaneous circulation (ROSC) on hospital arrival, and the efficacy of pH in predicting good neurological outcomes was compared. In patients with ROSC on hospital arrival (N = 100), the initial pH values for good and poor neurological outcomes were 7.26 ± 0.14 and 7.09 ± 0.18, respectively (p < 0.001). In patients without ROSC on hospital arrival (N = 99), the initial pH values for good and poor neurological outcomes were 7.06 ± 0.23 and 6.92 ± 0.15, respectively (p = 0.007). The pH associated with good neurological outcome was much lower in patients without ROSC than in those with ROSC on hospital arrival (P = 0.003). A higher initial pH is associated with good neurological outcomes in patients with OHCA. However, the pH for a good or poor neurological outcome depends on the ROSC status on hospital arrival.

Spontaneous hemodynamic improvement after balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary hypertension is observed within a short term after balloon pulmonary angioplasty.

Natural hemodynamic changes after balloon pulmonary artery angioplasty (BPA) in a unified state without oxygen administration in patients with chronic thromboembolic pulmonary hypertension (CTEPH) remains undetermined. This study aimed to clarify the delayed changes in the hemodynamics after BPA in patients with CTEPH. We analyzed 73 consecutive patients with CTEPH who underwent BPA between July 2014 and December 2022. We extracted and evaluated hemodynamic data of the right heart catheter without oxygen administration immediately before and after the first BPA; and immediately before the second BPA, as the "post-delayed changes" after BPA. BPA significantly improved the mean pulmonary artery pressure (mPAP, mmHg) and pulmonary vascular resistance (PVR, dyn-s/cm5) from 36 (32-43) mmHg and 449 (312-627) dyn-s/cm5 before the first BPA to 28 (23-32) mmHg and 275 (217-366) dyn-s/cm5 immediately after BPA, and further significantly improved the values to 23 (20-28) mmHg and 225 (175-301) dyn-s/cm5 post-delayed changes after BPA, respectively. Improvement observed on account of delayed changes was observed both with and without pulmonary hypertension drugs. The delayed changes were observed during a period of 5-180 days, which did not correlate with the changes in mPAP and PVR. Hemodynamic improvement owing to BPA was observed immediately after BPA; however, further improvement was observed as a result of delayed changes. mPAP improved by 3.4 ± 5.2 mmHg and PVR by 53 (10-99) dyn-s/cm5 as delayed improvement. mPAP and PVR showed delayed improved by approximately 10% of their values before BPA.

Adaptive enhancement of apatite crystal orientation and Young's modulus under elevated load in rat ulnar cortical bone.

Functional adaptation refers to the active modification of bone structure according to the mechanical loads applied daily to maintain its mechanical integrity and adapt to the environment. Functional adaptation relates to bone mass, bone mineral density (BMD), and bone morphology (e.g., trabecular bone architecture). In this study, we discovered for the first time that another form of bone functional adaptation of a cortical bone involves a change in bone quality determined by the preferential orientation of apatite nano-crystallite, a key component of the bone. An in vivo rat ulnar axial loading model was adopted, to which a 3-15 N compressive load was applied, resulting in approximately 440-3200 µÉ› of compression in the bone surface. In the loaded ulnae, the degree of preferential apatite c-axis orientation along the ulnar long axis increased in a dose-dependent manner up to 13 N, whereas the increase in BMD was not dose-dependent. The Young's modulus along the same direction was enhanced as a function of the degree of apatite orientation. This finding indicates that bone has a mechanism that modifies the directionality (anisotropy) of its microstructure, strengthening itself specifically in the loaded direction. BMD, a scalar quantity, does not allow for load-direction-specific strengthening. Functional adaptation through changes in apatite orientation is an excellent strategy for bones to efficiently change their strength in response to external loading, which is mostly anisotropic.

Display of PETase on the Cell Surface of Escherichia coli Using the Anchor Protein PgsA.

Enzymatic degradation of polyethylene terephthalate (PET) is attracting attention as a new technology because of its mild reaction conditions. However, the cost of purified enzymes is a major challenge for the practical application of this technology. In this study, we attempted to display the surface of the PET-degrading enzyme, PETase, onto Escherichia coli using the membrane anchor, PgsA, from Bacillus subtilis to omit the need for purification of the enzyme. Immunofluorescence staining confirmed that PETase was successfully displayed on the surface of E. coli cells when a fusion of PgsA and PETase was expressed. The surface-displaying E. coli was able to degrade 94.6% of 1 mM bis(2-hydroxyethyl) terephthalate in 60 min, and the PET films were also degraded in trace amounts. These results indicate that PgsA can be used to present active PETase on the cell surface of E. coli. This technique is expected to be applied for efficient PET degradation.

UV mutagenesis improves growth potential of green algae in a green algae-yeast co-culture system.

It is known that co-cultivation of green algae with heterotrophic microorganisms, such as yeast, improves green algae's growth potential and carbon dioxide fixation, even under low CO2 concentration conditions such as the atmosphere. Introducing mutations into green algae is also expected to enhance their growth potential. In this study, we sought to improve the growth potential of a co-culture system of the green algae Chlamydomonas reinhardtii and the yeast Saccharomyces cerevisiae by introducing mutations into the green algae. Additionally, we performed a transcriptome analysis of the co-culture of the green algae mutant strain with yeast, discussing the interaction between the green algae mutant strain and the yeast. When the green algae mutant strain was co-cultured with yeast, the number of green algae cells reached 152 × 105 cells/mL after 7 days of culture. This count was 2.6 times higher than when the wild-type green algae strain was cultured alone and 1.6 times higher than when the wild-type green algae strain and yeast were co-cultured. The transcriptome analysis also indicated that the primary reason for the increased growth potential of the green algae mutant strain was its enhanced photosynthetic activity and nitrogen utilization efficiency.

Investigation on bacterial capture and antibacterial properties of acid-treated Ti surface.

OBJECTIVES: Utilizing Ti and Ti alloys as dental materials established a huge spurt in the field of dentistry. Since implantation is an invasive procedure that involves tissue penetration, infection control is mandatory for increasing the success rate of the implant treatment. In this study, we aimed to assess the impact of the surface physicochemical properties of acid-treated Ti on microorganisms specifically bacteria. METHODS: After investigating the surface morphology and characteristics of acid-treated and untreated Ti sheets, we evaluated their potential to capture Escherichia coli (E. coli.) as well as the latter's survival on the surface of both types of sheets. Finally, we assessed the efficiency of the antibacterial properties exhibited by Ti against the oral microflora. RESULTS: SEM images revealed surface roughening of the acid-treated Ti represented by significantly irregular shape. Moreover, the acid-treated Ti exhibited remarkable hydrophobicity. A quantitative evaluation confirmed that acid-treated Ti has higher bacterial capture and antibacterial properties than untreated Ti. Further experiments showed similar effects of both types of Ti not only on E. coli but also on oral microflora. SIGNIFICANCE: Results suggest that acid treatment of Ti surface is a potent technique for enhancing the antibacterial properties of Ti-derived materials.

Building a machine-learning model to predict optimal mevalonate pathway gene expression levels for efficient production of a carotenoid in yeast.

Simultaneous modification of the expression levels of many metabolic enzyme genes results in diverse expression ratios of these genes; however, the relationship between gene expression levels and chemical productivity remains unclear. However, clarification of this relationship is expected to improve the productivity of useful chemicals. Supervised machine learning is considered to be an effective means to clarify this relationship. In this study, to improve the productivity of carotenoids in yeast Saccharomyces cerevisiae, we aimed to build a machine-learning model that can predict the optimal gene expression level for carotenoid production. First, we obtained data on the expression levels of mevalonate pathway enzyme genes and carotenoid production. Then, based on these data, we built a machine-learning model to predict carotenoid productivity based on gene expression levels. The prediction accuracy of 0.6292 (coefficient of determination) was achieved using the test data. The maximum predicted carotenoid productivity was 4.3 times higher in the engineered strain than in the parental strain, suggesting that the expression levels of the mevalonate pathway enzyme genes tHMG1 and ERG8 have a particularly large impact on carotenoid productivity. This study could be one of the important achievements in addressing the uncertainty of genotype-phenotype correlations, which is one of the challenges facing metabolic engineering strategies.

Thioester-Based Coupled Fluorogenic Assays in Microdevice for the Detection of Single-Molecule Enzyme Activities of Esterases with Specified Substrate Recognition.

Single-molecule enzyme activity assay is a platform that enables the analysis of enzyme activities at single proteoform level. The limitation of the targetable enzymes is the major drawback of the assay, but the general assay platform is reported to study single-molecule enzyme activities of esterases based on the coupled assay using thioesters as substrate analogues. The coupled assay is realized by developing highly water-soluble thiol-reacting probes based on phosphonate-substituted boron dipyrromethene (BODIPY). The system enables the detection of cholinesterase activities in blood samples at single-molecule level, and it is shown that the dissecting alterations of single-molecule esterase activities can serve as an informative platform for activity-based diagnosis.

Solid-state inorganic and metallic adhesives for soft biological tissues.

Currently, the soft-tissue adhesives used in clinical practice are glue-type organic adhesives. However, there is a demand for new types of adhesives, because the current organic adhesives present challenges in terms of their biocompatibility and adhesion strength. This review summarizes the discovery and development of inorganic and metallic adhesives designed for soft biological tissues while focusing on immobilization of medical divices on soft tissues. These new types of adhesives are in a solid state and adhere directly and immediately to soft tissues. Therefore, they are called "solid-state adhesives" to distinguish them from the currently used glue-type adhesives. In previous studies on inorganic solid-state adhesives, oxides and calcium phosphates were used as raw materials in the form of nanoparticles, nanoparticle-coated films, or nanoparticle-assembled porous plates. In previous studies on metallic solid-state adhesives, only Ti and its alloys were used as raw materials. This review also discusses the future perspectives in this active research area.

Effect of transcranial static magnetic stimulation over unilateral or bilateral motor association cortex on performance of simple and choice reaction time tasks.

Background: Transcranial static magnetic stimulation (tSMS) is a non-invasive brain stimulation technique that place a strong neodymium magnet on scalp to reduce cortical excitability. We have recently developed a new tSMS device with three magnets placed close to each other (triple tSMS) and confirmed that this new device can produce a stronger and broader static magnetic field than the conventional single tSMS. The aim of the present study was to investigate the effect of the conventional single tSMS as well as triple tSMS over the unilateral or bilateral motor association cortex (MAC) on simple and choice reaction time (SRT and CRT) task performance. Methods: There were two experiments: one involved the conventional tSMS, and the other involved the triple tSMS. In both experiments, right-handed healthy participants received each of the following stimulations for 20 min on different days: tSMS over the unilateral (left) MAC, tSMS over the bilateral MAC, and sham stimulation. The center of the stimulation device was set at the premotor cortex. The participants performed SRT and CRT tasks before, immediately after, and 15 min after the stimulation (Pre, Post 0, and Post 15). We evaluated RT, standard deviation (SD) of RT, and accuracy (error rate). Simulation was also performed to determine the spatial distribution of magnetic field induced by tSMS over the bilateral MAC. Results: The spatial distribution of induced magnetic field was centered around the PMd for both tSMS systems, and the magnetic field reached multiple regions of the MAC as well as the sensorimotor cortices for triple tSMS. SD of CRT was significantly larger at Post 0 as compared to Pre when triple tSMS was applied to the bilateral MAC. No significant findings were noted for the other conditions or variables. Discussion: We found that single tSMS over the unilateral or bilateral MAC did not affect performance of RT tasks, whereas triple tSMS over the bilateral MAC but not over the unilateral MAC increased variability of CRT. Our finding suggests that RT task performance can be modulated using triple tSMS.

Reaction time and brain oscillations in Go/No-go tasks with different meanings of stimulus color.

Color has meaning in particular contexts, and the meaning of color can impact behavioral performance. For example, the meaning of color about traffic rules (blue/green and red mean "go" and "stop" respectively) influences reaction times (RTs) to signals. Specifically, in a Go/No-go task, RTs have been reported to be longer when responding to a red signal and withholding the response to a blue signal (Red Go/Blue No-go task) than when responding to a blue signal and withholding the response to a red signal (Blue Go/Red No-go task). However, the neurophysiological background of this phenomenon has not been fully understood. The purpose of this study was to investigate the brain oscillatory activity associated with the effect of meaning of color on RTs in the Go/No-go task. Twenty participants performed a Blue simple reaction task, a Red simple reaction task, a Blue Go/Red No-go task, and a Red Go/Blue No-go task. We recorded responses to signals and electroencephalogram (EEG) during the tasks and evaluated RTs and changes in spectral power over time, referred to as event-related synchronization (ERS) and event-related desynchronization (ERD). The behavioral results were similar to previous studies. The EEG results showed that frontal beta ERD and theta ERS were greater when signals were presented in blue than red color in both simple reaction and Go/No-go tasks. In addition, the onset of theta ERS was delayed in the Red Go than Blue Go trial in the Go/No-go task. The enhanced beta ERD may indicate that blue signals facilitate motor response, and the delayed onset of theta ERS may indicate the delayed onset of cognitive process when responding to red signals as compared to blue signals in the Go/No-go task. Thus, this delay in cognitive process can be involved in the slow response in the Red Go/Blue No-go task.

Generation of glucocorticoid-producing cells derived from human pluripotent stem cells.

Adrenal insufficiency is a life-threatening condition resulting from the inability to produce adrenal hormones in a dose- and time-dependent manner. Establishing a cell-based therapy would provide a physiologically responsive approach for the treatment of this condition. We report the generation of large numbers of human-induced steroidogenic cells (hiSCs) from human pluripotent stem cells (hPSCs). Directed differentiation of hPSCs into hiSCs recapitulates the initial stages of human adrenal development. Following expression of steroidogenic factor 1, activation of protein kinase A signaling drives a steroidogenic gene expression profile most comparable to human fetal adrenal cells, and leads to dynamic secretion of steroid hormones, in vitro. Moreover, expression of the adrenocorticotrophic hormone (ACTH) receptor/co-receptor (MC2R/MRAP) results in dose-dependent ACTH responsiveness. This protocol recapitulates adrenal insufficiency resulting from loss-of-function mutations in AAAS, which cause the enigmatic triple A syndrome. Our differentiation protocol generates sufficient numbers of hiSCs for cell-based therapy and offers a platform to study disorders causing adrenal insufficiency.

Practical N-to-C peptide synthesis with minimal protecting groups.

Accessible drug modalities have continued to increase in number in recent years. Peptides play a central role as pharmaceuticals and biomaterials in these new drug modalities. Although traditional peptide synthesis using chain-elongation from C- to N-terminus is reliable, it produces large quantities of chemical waste derived from protecting groups and condensation reagents, which place a heavy burden on the environment. Here we report an alternative N-to-C elongation strategy utilizing catalytic peptide thioacid formation and oxidative peptide bond formation with main chain-unprotected amino acids under aerobic conditions. This method is applicable to both iterative peptide couplings and convergent fragment couplings without requiring elaborate condensation reagents and protecting group manipulations. A recyclable N-hydroxy pyridone additive effectively suppresses epimerization at the elongating chain. We demonstrate the practicality of this method by showcasing a straightforward synthesis of the nonapeptide DSIP. This method further opens the door to clean and atom-efficient peptide synthesis.

Fabrication of a Fish-Bone-Inspired Inorganic-Organic Composite Membrane.

Biological materials have properties like great strength and flexibility that are not present in synthetic materials. Using the ribs of crucian carp as a reference, we investigated the mechanisms behind the high mechanical properties of this rib bone, and found highly oriented layers of calcium phosphate (CaP) and collagen fibers. To fabricate a fish-rib-bone-mimicking membrane with similar structure and mechanical properties, this study involves (1) the rapid synthesis of plate-like CaP crystals, (2) the layering of CaP-gelatin hydrogels by gradual drying, and (3) controlling the shape of composite membranes using porous gypsum molds. Finally, as a result of optimizing the compositional ratio of CaP filler and gelatin hydrogel, a CaP filler content of 40% provided the optimal mechanical properties of toughness and stiffness similar to fish bone. Due to the rigidity, flexibility, and ease of shape control of the composite membrane materials, this membrane could be applied as a guided bone regeneration (GBR) membrane.