Antimicrobial resistance (AMR) is one of the top ten global public health challenges. However, given the lack of a comprehensive assessment of worldwide AMR status, our objective is to develop a One Health-based system-wide evaluation tool on global AMR.Global Antimicrobial Resistance and Use Surveillance System (GLASS) and the European CDC. We investigated the overall- or sub-rankings of GOHI-AMR at the international/regional/national levels for data preprocessing and score calculation utilizing the existing GOHI methodology. Additionally, a correlation analysis was conducted between the GOHI-AMR and other socioeconomic factors.We have further developed the three-hierarchical Global One Health Index (GOHI)-AMR indicator scheme, which consists of five key indicators, 17 indicators, and 49 sub-indicators, by incorporating 146 countries’ data from diverse authoritative databases, including WHO's P > 0.05). GOHI-AMR was positively correlated with gross domestic product, life expectancy, and AMR-related publications, but negatively with natural growth rate and chronic respiratory disease. In contrast to Cyprus, the remarkably lower prevalence of "ESKAPE pathogens" in high-scoring Sweden and Denmark highlights Europe's huge gaps. China and Russia outperformed the other three BRICS countries on all key indicators, particularly India's ARR and Brazil's AMR laboratory network and coordination capacity. Furthermore, significant internal disparities in carbapenem-resistant Klebsiella pneumoniae (CRKP) and methicillin-resistant Staphylococcus aureus (MRSA) prevalence were observed between China and the USA, with MRSA prevalence both gradually declining, whereas CRKP prevalence has been declining in the USA but increasing in China, consistent with higher carbapenems-related indicator’ performance in USA.The average GOHI-AMR score for 146 countries is 38.45. As expected, high-income countries (HICs) outperform the other three income groups on overall rankings and all five key indicators of GOHI-AMR, whereas low-income countries unexpectedly outperform upper-middle-income countries and lower-middle-income countries on the antibiotics-resistant key indicator (ARR) and ARR-subordinate indicators, including carbapenem-, β-lactam-, and quinolone resistance, and even HICs on aminoglycoside resistance. There were no significant differences among the four groups on the environmental-monitoring indicator (GOHI-AMR is the most comprehensive tool currently available for the assessment of AMR status worldwide. We discovered unique features impacting AMR in each country and offered precise recommendations to improve the capacity to tackle AMR in low-ranking countries.The online version contains supplementary material available at 10.1186/s40249-022-01016-5. Antimicrobial Resistance Review, AMR would result in ten million annual deaths and a cumulative economic loss of GBP 100 trillion by 2050 , life expectancy and chronic respiratory disease, one environmental forest area –30, and P < 0.001). Except for four UMICs , the top 30 highest-scoring countries are mostly HICs, like France , Sweden , and Norway . The bottom 20 countries are all LMICs and LICs, like Cameroon  and Niger . Surprisingly, several HICs and UMICs, such as Seychelles , Gabon , and Albania , were also found in the ten countries with the lowest scores. This shows that income or economic development was not the only key factor affecting AMR in these countries , 38 upper-middle-income countries (UMICs), 41 low-middle-income countries (LMICs), and 19 low-income countries (LICs) . As showP < 0.001), whereas LICs unexpectedly outperformed UMICs and LMICs on the key indicator ARR (P < 0.001). Interestingly, we further discovered that LICs performed better than UMICs and LMICs on the indicators, carbapenem resistance (CAR), β-lactam resistance (BLA), and quinolone resistance (QUI), and even outperformed HICs on the indicator aminoglycoside resistance (AMI). Simultaneously, HICs outperformed UMICs only on AMI, with no difference between HICs, LMICs, and LICs. Surprisingly, there were no significant differences between the four groups on the indicators EAR , 2.1NTC , or NTP . Only eight countries, including the Netherlands, Austria, and Australia from HICs, Jordan from UMICs, and Vietnam from LMICs, scored more than 90 on the EAR. The remaining 130 countries all scored less than 40, which shows that national environmental surveillance networks need to be set up as soon as possible.In addition, we analyzed each key indicator across income-based national groups. In Fig. P < 0.001). In the sub-indicator CR-ABA (carbapenem-resistant Acinetobacter baumannii), HICs, LMICs, and LICs scored substantially higher than UMICs (P < 0.001). In CR-ECO (carbapenem-resistant Escherichia coli), its scores in LMICs and LICs were higher than that in UMICs. Moreover, HICs and LICs outperformed UMICs and LMICs in the two carbapenem-resistant sub-indicators (CR-ABA and CR-ECO). Surprisingly, in the MR-SA , LICs scored even much higher than HICs, suggesting a distinct AMR epidemic pattern different from Klebsiella pneumoniae and E. coli. Between HICs and LICs, there were no significant differences in the aminoglycoside-resistant and quinolone-resistant indicators (AMI and QUI), and both groups scored higher than UMICs and LMICs. HICs and LICs had considerably higher sub-scores than UMICs and LMICs, especially for the sub-indicator QNR-KPN (quinolone-resistant K. pneumoniae). As expected, HICs continue to do better than the other three income groups in most antimicrobial-bacteria combinations. However, AMR is widespread in most UMICs and LMICs, in part because of the high use of antimicrobials during rapid economic growth , GNI per capita , life expectancy , and the number of PubMed publications on One Health & AMR   was discovered  and four European countries with relatively low scores . The key indicators of ARR’s scores are depicted in Fig. The GOHI-AMR rankings of the BRICS countries have significant implications for the majority of LMICs, as well as a few LICs and UMICs. The average GOHI-AMR overall score of the BRICS countries is 41.60. China  and Russia  performed significantly better than India , Brazil , and South Africa .As expected, the BRICS countries demonstrate some variation in their GOHI-AMR indicators in Fig. China and the USA are the world's largest developing and developed countries with a massive population, vast geographical territory, and enormous AMR data throughout all 31 provincial-level administrative divisions (PLADs) in China or 55 states in the USA. Here, the differences in AMR prevalence across different Chinese PLADs or states in the USA are substantially more dramatic than within other countries. Thus, from 2015 to 2019, we studied AMR rates for gram-positive MRSA and gram-negative CRKP in every PLAD of China or state of the USA Fig. A–F.Fig. As shown in Fig. Acinetobacter baumannii in HICs are significantly higher than those in LICs but lower than in UMICs and LMICs. Moreover, utilizing AMR surveillance data from ECDC, there are still some HICs, such as Cyprus and Malta, with a higher prevalence of ESKAPE and no effective preventative or control measures, demonstrating that even within HICs, huge AMR discrepancies also exist; Secondly, among the monitoring-related key indicators ASS, less than one-third of HICs scored over 60 on the indicator AMC . The primary issue is the inadequacy of national monitoring of animal antibiotic consumption, with only New Zealand scoring 75 on the sub-indicator ACA. In the future, UMICs, LMICs, and LICs will confront similar AMR challenges.Consistent with the positive correlation between GOHI-AMR and GDP, GNI, and domestic health expenditures, the HICs significantly outperformed the other three income nation groups, with all five key indicators dramatically above the global average. Particularly for the key indicator ACO, nearly all of the HICs have accounted for the proper use of antibiotics not just in humans but in animals and environments as well. Simultaneously, HICs have numerous existing challenges. Firstly, unexpectedly, in the sub-indicators MR-SA and AR-ABA, the prevalence of MRSA and aminoglycosides-resistant Except for the key indicator ARR in LICs, the average scores of the remaining 4 key indicators within the other three income groups are all lower than the global average. Due to some advances in the optimization of antibiotics, particularly in animals, the key indicators ASS and ACO are marginally better in UMICs compared to LMICs and LICs. However, there are huge gaps in the monitoring of animals and plants, especially in LICs. In addition, UMICs and LMICs are striving to raise awareness of AMR within their populations. The public and AMR-related professionals, such as doctors, veterinarians, and farmers, have a greater understanding of antibiotics than those in LICs. Surprisingly, the majority of countries globally performed poorly on the ARR. Nonetheless, the performances of LICs were significantly higher than the world average and also exceeded those of UMICs and LMICs. In particular, the aminoglycoside and quinolone-resistant bacteria prevalence of LICs are even close to those of HICs. The performance of the other four key indicators, however, ranks lowest for LICs. As a result, LICs have increased their monitoring of AMR in humans and animals. National plans should include monitoring of the environment within a reasonable amount of time, and multidisciplinary collaboration should be taken into account when building scientific research platforms.Middle-income countries, encompassing UMICs and LMICs, face unique problems compared to HICs and LICs. Brazil and Argentina are the world's two largest meat suppliers . They peE. coli resistance patterns are distinct. We will consider more environmental aspects in future studies [Here, we confirmed multiple GOHI-AMR-related factors. However, as the majority of high-scoring countries are HICs and UMICs, and the majority of low-scoring countries are LICs and LMICs, it is unquestionable that economic factors continue to be the most important driver of AMR governance competence. Surprisingly, a few impoverished countries that implemented an early One Health-based response against AMR scored far higher on the GOHI-AMR than a great number of developed countries. Malaysia, for instance, developed a significant number of human, animal, and environmental AMR-related government departments in 1988 as part of its "National Surveillance of Antibiotic Resistance" initiative . Similar studies .The country's overall rankings under GHS-AMR and GOHI-AMR are nearly the same for the vast majority of European HICs. However, several UMICs with low GOHI-AMR overall rankings, such as Brazil , Argentina (81st/146 and 12th/195), and Armenia (107th/146 and 12th/195), scored rarely higher in GHS-AMR. Nonetheless, based on the sub-indicators ACH, ACA, RDT, and MSW originating from TrACSS, these differentiated-ranking countries have particularly severe deficiencies in animal and human antimicrobial consumption control, as well as multi-platform collaboration . In addiThis index system relies heavily on official international or national databases, such as the WHO's GLASS, GHS, and TrACSS, as well as authoritative monitoring databases, such as CARSS in China, the USA CDC, and the European CDC. AMR datasets in these industrialized countries are quite complete, whereas the majority of LICs and LMICs lack substantial AMR data. Moreover, the current analysis adopts an indicator evaluation system that requires at least one year of data; the most recent data from GHS in 2021, TrACSS and Europe CDC in 2020 were collected. The rest of the data including GLASS is from 2019, which shows that there hasn't been a lack of continuous dynamic change throughout the evaluation, and the data utilized is from several years ago, which makes it impossible to compare horizontally.This study is, to the best of our knowledge, the most comprehensive investigation to date of global AMR status within the framework of One Health. In particular, our findings demonstrate that AMR is still a serious global health concern, especially in LICs and LMICs, such as in sub-Saharan Africa. Meanwhile, establishing laboratory infrastructure and multidisciplinary platforms rapidly will be critical to addressing the enormous burden of AMR. Simultaneously, this will urgently require more extensive surveillance of AMR in humans, animals, and the surrounding environment.Additional file 1:Table S1: Technical file for GOHI-AMR.Additional file 2:Table S2: Index framework for GOHI-AMR. Table S3: Global rankings for 146 countries worldwide. Table S4: All the indicator scores for 146 countries worldwide.


We prepared a series of one-dimensional conjugated-material-based nanofibers with different morphologies and donor/acceptor (D/A) compositions by electrospinning for efficient photocatalytic hydrogen evolution. It was found that homogeneous D/A heterojunction nanofibers can be obtained by electrospinning, and the donor/acceptor ratio can be easily controlled. Compared with the single-component-based nanofibers, the D/A-based nanofibers showed a 34-fold increase in photocatalytic efficiency, attributed to the enhanced exciton dissociation in the nanofibrillar body. In addition, the photocatalytic activity of these nanofibers can be easily optimized by modulating the diameter. The results show that the diameter of the nanofibers can be conveniently controlled by the electrospinning feed rate, and the photocatalytic effect increases with decreasing fiber diameter. Consequently, the nanofibers with the smallest diameter exhibit the most efficient photocatalytic hydrogen evolution, with the highest release rate of 24.38 mmol/(gh). This work provides preliminary evidence of the advantages of the electrospinning strategy in the construction of D/A nanofibers with controlled morphology and donor/acceptor composition, enabling efficient hydrogen evolution. Hydrogen is a new energy source with extremely high potential for replacing fossil fuels because of its high energy density, low pollution, and low environmental impact ,2,3. HydOrganic semiconductor materials can be easily modified in terms of their electronic properties; their band gaps can be flexibly adjusted, and their wide absorption range and high charge carrier mobility have a wide range of applications in the field of photocatalytic hydrogen evolution ,9,10,11.Electrospinning is a reliable method for constructing one-dimensional nanomaterials benefiting from the advantages of adjustable nanoscale size, controllable composition and morphology, persistent process, high specific surface area, good mechanical flexibility/strength, simple processes, and low production costs for large-scale applications ,42,43,44Herein, we demonstrate a series of one-dimensional electrospun organic donor/acceptor (D/A) nanofibers, realizing controllable composition and morphology, as well as highly efficient photocatalytic evolution. Conjugated polymer PTB7−Th and nonfullerene acceptor EH−IDTBR  were sepw = 72 kDa), nonfullerene acceptor 4-thiazolidinone, 5,5′-dithiophene-2,7-diyl]bis]bis dithiophene] 3-fluoro-2[(2-ethylhexyl)car- bonyl]thieno thiophenediyl  with vigorous stirring at 50 °C for 4 h. Then. PEO or PVP chloroform solution was prepared at a mass concentration of 20 mg/mL, mixed with the above solution in equal volumes, and stirred magnetically for 2–4 h to obtain a homogeneous electrospinning precursor solution.Firstly, a solution of PTB7−Th/EH−IDTBR  was prepared at a mass concentration of 20 mg/mL by a mixed solvent of CHClThe colloidal solution was then filtered through a 0.45 μm syringe filter before use. Concentrations of solutions for electrospinning were calibrated by taking the solvent evaporation during the fabrication process into account. All samples were prepared using the same method unless stated otherwise.The schematic fabrication process of the D/A heterojunction-based electrospun nanofibers and the resulting morphology are shown in The morphologies of the conjugated electrospun nanofibers were inspected by optical microscopy  and field-e mission scanning electron microscopy  at an accelerating voltage of 5 kV. The chemical analysis of the electrospun nanofibers was performed by transmission electron microscopy  with an accelerating voltage of 200 kV. The UV-visible absorption spectra of the aqueous dispersion of the electrospun nanofibers were recorded on an HP 8453 spectrophotometer . For comparison, the film obtained by spin-coating an equal molar ratio of the EH−IDTBR and PTB7–Th chloroform solutions onto the quartz plate was also subjected to record its UV-visible absorption spectra. The photoluminescence spectra of conjugated polymers and their blends were recorded on a JobinYvon Fluorolog-3 spectrophotometer . Transmission FT-IR spectra were recorded on a Nicolet IS50  at room temperature, and samples were prepared by dropping the nanofiber aqueous dispersion on the pressed KBr pellets.2PtCl4 aqueous solution into the reactor and irradiating for 1 h to enable the formation of Pt nanoparticles cocatalysts before testing. The reaction was sealed with a quartz septum and held under vacuum for 30 min to remove the dissolved oxygen before testing. The photocatalytic reactions were illuminated with a solar simulator . The luminous power reaching the surface of the reaction solution was calibrated to be 80 mW/cm2 by a power meter. The produced gas was analyzed by a GC7900 gas chromatograph . Hydrogen was detected with a thermal conductivity detector, referencing standard gas with a known concentration of hydrogen. The sensor was standardized by injecting different volumes of hydrogen at the experimental condition and was polarized at +36 mV until reaching a stable value before every measurement.The hydrogen evolution measurements were performed on a Labsolar-IIIAG photocatalytic system  equipped with a 50 mL reactor. For the photocatalytic experiment using AA as the sacrificial agent, the electrospun nanofibers (4 mg) were dispersed into a mixture of 50 mL of AA solution  with ultrasonic for 30 min. The total concentration of the electrospun nanofibers for photocatalytic measurement in the reaction solution was 80 µg/mL. Pt cocatalysts (3 wt% of the electrospun nanofibers) were prepared by dissolving HIn the present study, we prepared two separate sets of samples. Firstly, a set of nanofiber heterojunctions with different D/A ratios was obtained by adjusting the donor/acceptor ratio in the solution. In this set of samples, we prepared similar fiber diameters to study the effect of different D/A ratios on photocatalysis. Secondly, we fixed the donor/acceptor ratio and varied the fiber diameter by controlling the feed rate of the solution, to study the effect of fiber diameter on photocatalytic hydrogen evolution.The optical properties of these nanofibers were examined by UV–visible–NIR absorption spectroscopy, as shown in The visual evidence of the morphology of the electrospun fibers was obtained by optical microscopy, as shown in We selected the donor polymer PTB7−Th and the nonfullerene acceptor EH−IDTBR as sources to explore the potential of conjugated-polymer-based electrospinning in photocatalytic hydrogen evolution. According to previous reports, this D/A combination causes strong visible-light absorption, type II energy level offset ,53, and The PL spectra of the nanofiber suspension were obtained by exciting the sample, similar to that prepared for the hydrogen evolution reaction with a 630 nm laser. As shown in v/v) for electrospinning. In addition, the diameter of the nanofibers could be easily tuned by controlling the electrospinning feed rate. For example, the average diameter of the D/A electrospun fibers significantly decreased from 2.1 μm to 0.8 μm by declining the solution feed rate from 0.20 to 0.08 mm/min. In addition, no typical signs of IDTBr or PTB7−Th aggregations could be observed in the fibers in our study.In order to obtain a clearer morphology of the D/A electrospun nanofiber obtained with different feed rates, scanning electron microscopy (SEM) was employed, as shown in Although all D/A solutions were electrospun successfully, the relationship between the dielectric constant of the solvent, which is a measure of the polarity of the solvent, and the average diameter of the fibers is still worth considering. It is proved that the solvent with a high dielectric constant has a higher net charge density in the solution. Therefore, as the charges carried by the jet increased, higher elongation forces were imposed on the jet under the electrical field, resulting in smaller beads and thinner fiber diameters ,55. HoweIn addition, to investigate the influence of composition on the hydrogen evolution, nanofibers with different D/A ratios and different matrixes were prepared by electrospinning, and the diameter was fixed at 800 nm by controlling the feed rate. The SEM images of electrospun fibers as stated above are shown in Meanwhile, at this point, the successful in situ reduction of the Pt cocatalyst on nanofibers was confirmed by characterizing the distribution of each element in the nanofibers via SEM mapping d,h. The 2 evolution measurements.In an effort to investigate the effect of nanofiber diameter on the hydrogen evolution of these conjugated polymers-based electrospun nanofibers, a series of one-dimensional electrospun nanofibers with diameters of approximately 0.8–2.1 μm were dispersed into the photocatalytic reactor with a controlled mass of 4 mg for each test. Meanwhile, platinum was in situ photodeposited on the composite nanofiber surfaces during H2 versus time is presented in 2 were produced in 5 h, respectively. These nanofibers achieved satisfactory levels of hydrogen evolution efficiency, especially the 0.8 μm nanofibers, which achieved 24.38 mmol/(gh). In addition, it could be found that the performances of the catalysts were significantly influenced by the diameters of the nanofibers. Thicker nanofibers displayed reduced hydrogen evolution efficiency in the experiment because the surface area of the thick nanofiber was smaller, and the exciton migration path was longer. In comparison, the smallest diameter of the D/A nanofibers fabricated in this experiment was 800 nm, which is not comparable with the distance of the electron transfer and the exciton diffusion length. This demonstrates that high photocatalytic hydrogen evolution efficiency may originate from the fact that part of the active subchains is effectively stretched and oriented along the fiber axis during electrospinning, adopting a more extended chain conformation, accompanied by an increase in the associated conjugation length and the arrangement that supports interchain interactions with nearby subchains.Nanofibers with different diameters and PEO matrixes were first tested, and the amount of generated HIn an attempt to determine the effect of different D/A composition mass ratios on the efficiency of the photocatalytic hydrogen evolution of electrospun nanofibers, fibers using a uniform PEO matrix containing D/A mass ratios of 3:7, 5:5, 7:3, and 10:0 were prepared, and their corresponding photocatalytic hydrogen production was tested under the same conditions as mentioned above, as shown in 2 generation in nanofibers under xenon lamp irradiation is shown in Given the low molecular weight, chain rigidity, and limited solubility of conjugated polymers, especially small-molecule organic semiconductors with poor molecular entanglement, preparation of conjugated polymers-based nanofibers by electrospinning normally requires the assistance of high-molecular-weight flexible chain-insulating polymers. PEO and PVP, two widely used flexible insulating polymers, were employed to blend with the conjugated polymers for electrospinning, and the effect of different matrixes on the photocatalytic hydrogen evolution performance of nanofiber was investigated . Althoug−1 h−1 for Run 1, 18.55 mmol g−1 h−1 for Run 2, and 19.88 mmol g−1 h−1 for Run 3, which is probably attributed to the high photocatalytic activity, as well as the dispersion of nanofibers in the first few cycles. The prolongation of irradiation resulted in a decrease in HER to 6.36 mmol g−1 h−1 for Run 4. Nanofibers before and after photocatalysis were analyzed by Fourier-transform infrared spectroscopy (FT-IR), as shown in −1 were attributed to PEO contained in the electrospun fibers. After the photocatalytic reaction, the stretching bands at 2922 cm−1 disappeared, indicating that PEO was removed from the nanofibers during the hydrogen evolution process. However, few strong peaks presented at 1705 cm−1, 1650 cm−1, 1320 cm−1, and 1110 cm−1, which corresponded to the C=O, C=C, C–N, and C–F stretching, respectively, suggesting that D/A nanofibers have long-term photostability.In addition, the photocatalytic stability of the nanofiber suspension was evaluated via a continuous photocatalytic reaction under irradiation for 20 h. The amount of hydrogen generated as a function of time is shown in Meanwhile, in our study, we prepared nanofibers with a diameter of about 800 nm and a donor/acceptor/PEO mass ratio of 3/7/10, and In summary, we successfully prepared a series of one-dimensional donor/acceptor (D/A) heterojunction-based conjugated polymer nanofibers using electrospinning technology and achieved efficient photocatalytic hydrogen evolution. The relationship between nanofiber diameter and photocatalytic hydrogen production efficiency was explored, and efficiencies of up to 24 mmol/(gh) in the visible range were obtained. The D/A composition of the conjugated polymer nanofibers was optimized to obtain high photocatalytic hydrogen production. In addition, by blending different hydrophilic polymers with the D/A conjugated polymers for electrospinning, an optimal matrix was selected to obtain efficient photocatalytic hydrogen evolution. Overall, this work proves that electrospinning is an effective strategy to enhance the photocatalytic activity of conjugated polymers, thus expanding the application potential of conjugated polymer-based nanofibers.


Genetic Basis of Tolerance Induction Defects Underlying the Development of Autoimmune Pathologies” we envisioned four areas of interest for this Research Topic: Area 1 - the genetic basis for tolerance induction defects underlying any single or multiple autoimmune disease states; Area 2 - the controversy concerning how well some animal models, in particular mice, inform the basis of various autoimmune pathologies in humans; Area 3 - how gene variants disrupt Treg/Breg development or activity resulting in autoimmune disease states; and Area 4 - genes x environment interactions contributing to various autoimmune states.In our initial call for review articles for the Research Topic “Kissler’s “Genetic Modifiers of Thymic Selection and Central Tolerance in Type 1 Diabetes” presents a section on TAGAP which may be of interest for those studying thymic migration of developing T-cells. Hocking and Buckner’s “Genetic basis of defects in immune tolerance underlying the development of autoimmunity” presents a section on PADI2 and PADI4 variants in rheumatoid arthritis (RA). PADI2 and PADI4 are enzymes responsible for the conversion of arginine to citrulline. Recent work has indicated that post translational modifications like citrullination can cause the creation of neoepitopes in type 1 diabetes . ThrRoach and Morel’sGenetic Variations Controlling Regulatory T Cell Development and Activity in Mouse Models of Lupus-Like Autoimmunity” focuses on this topic in the context of SLE. One section that may be of particular interest delves into the genes that regulate Treg metabolism and how this may affect their functionality. Raugh et. al.’s “Nature vs. nurture: FOXP3, genetics, and tissue environment shape Treg function” provides a deep dive into the biology of Tregs covering diverse topics from their heterogeneity, to the genetic, epigenetic, and non-coding RNA control of the development and activity of these cells. Topic Area 4 is also touched upon, as the role of microenvironmental cues, such as microbiome, is briefly covered. Finally, this review discusses how these areas impact possible Treg-based therapy development.Two review articles in this Research Topic focus on the biology of Tregs with a special emphasis on their stability. Di Lorenzo et al.’s “Natural history of type 1 diabetes on an immunodysregulatory background with genetic alteration in B-cell activating factor receptor: A case report” details the identification of a clinical case of T1D and common variable immunodeficiency in a patient with a low T1D-risk score putatively caused by the monoallelic H159Y mutation in TNFRSF13C (BAFFR). Zhong et al.’s “Herpesvirus entry mediator on T cells as a protective factor for myasthenia gravis: A Mendelian randomization study” utilized Mendelian Randomization to identify two SNPs (rs1886730 and rs2227313) in TNFRSF14 associated with herpesvirus entry mediator (HVEM) expression on T-cells and protection from myasthenia gravis. This adds to the growing body of evidence on the role of HVEM - BTLA interactions in modulating autoimmune diseases, just recently reviewed in (Finally, while we set out to focus solely on review articles for this Topic, two primary research articles were submitted that the Editors felt sufficient to include within the scope of our original goals for this Topic. Together, the articles in this Research Topic provide an up-to-date overview on genetic contributions to immune tolerance pathways and autoimmunity.JJR, LM, Y-GC, DVS were all Topic Editors for this Research Topic and contributed to the preparation of this Editorial. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Background and Objectives: Cardiopulmonary exercise testing can be used to quantify exercise capacity in patients with heart failure with reduced ejection fraction (HfrEF). Lung fluid levels as measured non-invasively by remote dielectric sensing (ReDSTM), often correlate with intracardiac filling pressures. The change in lung fluid levels in patients with HfrEF during cardiopulmonary exercise testing is unknown. Materials and Methods: Patients with chronic HfrEF who underwent cardiopulmonary exercise testing between October 2021 and March 2022 were prospectively included in this proof-of-concept study, with ReDS values measured before and after testing. Results: Thirteen patients  years, 69% men, plasma B-type natriuretic peptide 141  pg/mL) were included. Median peak oxygen consumption was 11.4  mL/kg/min. During the test, ReDS values increased from 25% to 32% only in one patient on inotropic support, whereas ReDS values remained unchanged in the other 12 patients. The former patient remained hospitalized, whereas the other patients were dischargeable without any new incidence of clinical events during the observational period . Conclusions: The ReDS system may be a feasible complementary tool to noninvasively assess the changes in lung fluid levels during cardiopulmonary exercise testing. The clinical implications of ReDS values during exercise needs further investigation. Typical failure . This caTM, Sensible Medical Innovations Ltd., Netanya, Israel) system is a novel electromagnetic-based modality to quantify lung fluid volume noninvasively. Prior data has suggested that lung fluid volume levels measured with ReDS , according to the guidelines . All pat2, production of carbon dioxide, and minute ventilation were measured during the tests on a breath-by-breath basis. Peak VO2 was defined as the highest mean VO2 over 20 s during the exercise.Continuous data of VOConsidering the Borg scale, which indicated patients’ objective fatigue in a range of 6–20, a score above 17 was targeted to terminate the tests. The respiratory exchange ratio was targeted at above 1.10.ReDS values were measured just before and after CPET in all patients. ReDS employs low-power electromagnetic signals emitted between two sensors embedded in wearable devices . The anap values less than 0.05 were considered significant.All continuous data are presented as medians with interquartile range (IQR). Categorical data are presented as numbers and percentages. The primary aim of the study is to determine the change in ReDS values prior to and after CPET. Changes in ReDS values during exercise tests were analyzed using Wilcoxon signed-rank test. All calculations were performed with SPSS Statistics 23.0 software , and two-sided Thirteen patients in total were included, with all of them completing CPET without complications. Median age was 41  years, and 69% were men . Half of2 was 11.4  mL/kg/min, and the minute ventilation/carbon dioxide production slope was 33.1 . The procedures were performed during their hospitalization for six patients, and in outpatient clinics for the remaining seven patients.Median (IQR) peak VOp = 0.18; 2 of 16.1 mL/kg/min was higher compared to the majority of the study cohort.All patients completed ReDS measurements just before and after cardiopulmonary exercise tests without any troubles and measurement errors. Overall, ReDS values did not significantly change pre- and post-CPET in nearly all patients  days; Of these, five patients were hospitalized at the time of testing and were eventually discharged.In this preliminary, proof-of-concept, prospective study, we assessed the feasibility of ReDS measurements before and after CPET in patients with chronic HFrEF, in order to quantify the change in lung fluid levels during exercise. We observed no significant change in ReDS values in the majority of patients, except for a single patient dependent on inotropic support, whose ReDS value increased from 25% to 32%.2 are not entirely known.CPET is an established diagnostic modality to objectively quantify patients’ exercise capacity in the setting of chronic heart failure, offering incremental risk prognostication over the spectrum of heart failure progression ,8. Peak Incremental changes in intracardiac pressure during exercise are one of the major causes of dyspnea in patients with chronic HFrEF, and hemodynamic monitoring during exercise using invasive right heart catheterization can be used to accurately assess for these changes ,9,10. AlThe ReDS system is a novel noninvasive tool used to quantify lung fluid volume, which correlates well with intracardiac filling pressures by right heart catheterization and intraparenchymal fluid using high resolution computed tomography, when measured at rest condition ,6,11. Th2, requires further time-to-event analyses. Furthermore, strategies to aggressively intervene upon the increase in ReDS values during exercise remain in need of further prospective analysis.We demonstrated only the feasibility of measuring ReDS during exercise, whereas the utility of conducting ReDS measurements during exercise as compared with other modalities remains unknown. The association between the change in ReDS during exercise and ventilator efficiency parameters also remains unknown. Of note, the patient observed with increased ReDS values during exercise had relatively preserved exercise capacity. Whether the increase in ReDS values during exercise has an independent and additional prognostic impact upon conventional ventilator efficiency parameters, including peak VOThis is a preliminary proof-of-concept study, and has several limitations. All participants had reduced or mildly reduced ejection fraction, and the applicability of our findings to other etiologies, including heart failure with preserved ejection fraction, requires further analysis. With a small sample size and a skewed distribution of the outcome towards the null, larger scale studies are needed in order to understand the phenotypes of patients who have clinically meaningful changes in ReDS values following exercise. We did not compare the ReDS values with any other modalities that assess lung fluid amounts, and we only showed the feasibility of taking ReDS measurements during CPET. The usefulness of the ReDS system should be validated by comparison with other modalities in subsequent studies.The ReDS system may be a feasible complementary tool to noninvasively assess the changes in lung fluid amounts during cardiopulmonary exercise testing. Its clinical implication needs further investigation.


Autism Spectrum Disorder (ASD) is a progressive neurodevelopmental disorder mainly characterized by deficits in social communication and stereotyped behaviors and interests. Here, we aimed to investigate the state of several key players in the dopamine and glutamate neurotransmission systems in the valproic acid (VPA) animal model that was administered to E12.5 pregnant females as a single dose (450 mg/kg). We report no alterations in the number of mesencephalic dopamine neurons or in protein levels of tyrosine hydroxylase in either the striatum or the nucleus accumbens. In females prenatally exposed to VPA, levels of dopamine were slightly decreased while the ratio of DOPAC/dopamine was increased in the dorsal striatum, suggesting increased turn-over of dopamine tone. In turn, levels of D1 and D2 dopamine receptor mRNAs were increased in the nucleus accumbens of VPA mice suggesting upregulation of the corresponding receptors. We also report decreased protein levels of striatal parvalbumin and increased levels of p-mTOR in the cerebellum and the motor cortex of VPA mice. mRNA levels of mGluR1, mGluR4, and mGluR5 and the glutamate receptor subunits NR1, NR2A, and NR2B were not altered by VPA, nor were protein levels of NR1, NR2A, and NR2B and those of BDNF and TrkB. These findings are of interest as clinical trials aiming at the dopamine and glutamate systems are being considered. Autism spectrum disorder (ASD) is a neurodevelopmental disorder affecting an increasing proportion of the population and that is mainly characterized by the presence of social deficits and restricted and repetitive behavior and interests . ManagemDespite the high heterogeneity in ASD symptoms and etiology, the occurrence of shared symptoms suggests common deficits in common neurodevelopmental pathways ,13,14,15NRX1-3 (neurexin 1-3), NLGN1, 3, 4 , CNTNAP2 (contactin-associated protein 2), and SHANK 1-3 (SH3 and multiple ankyrin repeat domains proteins) -Dopamine, [2H5]-dihydroxyphenyl acetic acid, [13C6]-homovanillic acid, [2H4]-3-methoxytyramine, respectively. Within run accuracy and precision were evaluated by assaying the quality control (QC) samples with three concentration levels  three times in a single analytical run while the between run accuracy and precision were performed by assaying the QC samples with tree concentration levels four times in at least four separate days. Accuracy error was expressed as a bias and the precision was expressed as the coefficient of variation (CV). The acceptance criteria for QCs were met for all compounds during the analytical analysis (Bias = ± 15% and CV ≤ 15%). Experiments were performed under ISO 9001 procedures. Data are expressed as pg of DA/ug of proteins.Ultra-performance liquid chromatography–tandem mass spectrometry detection was used to quantify dopamine and 3 of its metabolites, dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA) and 3-methoxytyramine (3-MT) in striatal regions and nucleus accumbens following protein precipitation by acetonitrile  and VPA (n = 14) in total) were sacrificed, brains were retrieved, regions of interest were either dissected out from the frozen brain  and VPA 1 to 5 (n = 5)) or through punches  and VPA 1 to 9 (n = 9), nucleus accumbens: saline 10 to 14 (n = 5) and VPA 10 to 14 (n = 5), motor cortex: saline 1 to 9 (n = 9) and VPA 1 to 9 (n = 9)). Proteins were extracted using 1% sodium dodecyl sulfate (SDS) solution in Tris HCl 0.1M with ethylenediaminetetraacetyl (EDTA) 0.01M and phenylmethylsulfonyl fluoride (PMSF), protease inhibitor, and phosphatase inhibitor at 1%. Equal amounts of proteins from lysates were separated by SDS-PAGE and migrated proteins were transferred to nitrocellulose membranes . After blocking the membranes at room temperature for 1 h in Tris Buffer Solution with Tween-20 0.1 M (TBST) at pH 7.4 and 5% non-fat milk, blots were incubated with corresponding primary antibodies at room temperature for 3 h. The blots were then washed three times in TBST and incubated with HRP-conjugated secondary antibodies overnight at 4 °C. Following 3 washes in TBST, the blots were incubated with ECL reagent . For quantification, the films were scanned by a PXi image system and gray signals were analyzed by GeneTools software , and normalized to that of corresponding internal controls (actin or α-tubulin). The following primary antibodies were used at the dilution of 1/500 to 1/1500: TH, BDNF, TrkB/TrkB-T1, LC3-I/II, DARPP32, p-DARPP-32, mTOR 7C10, P-mTOR ser 2448, ERK1/2, and P-ERK1/2 , parvalbumin, NR2A, NR2B , and NR1 . A-tubulin  and β-actin were used at a  dilution .Male mice  and VPA (n = 8)) were sacrificed, brains were collected, and striatal, cerebellar, and cortical regions were dissected out and frozen in −80 °C until use. Total RNA was isolated using TRIzol Reagent/chloroform, then purified using a NucleoSpin RNA kit  and quantified using NanoDrop ND-1000 spectrophotometer . RNA integrity was evaluated by an Agilent 2100 Bioanalyzer System. All RNAs had an RNA integrity number above 7. Reverse transcription was performed on 1μg of total RNA for each sample using Verso cDNA Synthesis kit . qPCR was performed on LightCycler 480 system . Ct values were averaged from triplicates. Results were subtracted to the mean Ct of the housekeeping gene Gapdh (ΔCt) and log transformed (2−ΔCt). Primer sequences are provided in Male mice  and analyzed using GraphPad Prism-7 software  unless otherwise indicated in the figure legends. Immunoblots, qPCR and histological measures that followed a normal distribution were analyzed using Student’s We have previously shown that mice pre-exposed to VPA (450 mg/kg) at E 12.5 showed major social deficits , in linep < 0.05) associated with an increase in the DOPAC/DA ratio (p < 0.05) that generally indicates a higher turnover rate of dopamine metabolism. No other alteration in the levels of dopamine, DOPAC, HVA, and 3-MT in any of the brain regions explored was found.Given the stable number of dopamine neurons and TH protein levels within the mesolimbic and nigrostriatal pathways, we aimed to measure dopamine and metabolite levels within these pathways. We first measured dopamine levels by HPLC in saline and VPA male mice and found no alteration within the striatum or the nucleus accumbens A. We nexThese results indicate slight but significant decreases in dopamine levels suggesting a potential role of dopamine in social deficits and motor disorders reported in VPA mice .We measured mRNA levels of major dopamine and glutamate receptors within target brain areas that are suspected to be implicated in major ASD social and motor symptomatology: the nucleus accumbens A, the stNR1, NR2A, NR2B, mGluR1, mGluR4, and mGluR5 in any of the brain regions examined   . Additioebellum) , as prevWe undertook further analysis of major molecules implicated in the dopamine signaling in main dopaminergic brain regions by immunoblotting . We analWe also analyzed levels of TrkB and its truncated isoform TrkB-T1  and of pGiven the major implications of the dopaminergic and glutamatergic neurotransmission systems in the pathophysiology of ASD, we aimed to determine the state of various players in these systems in the VPA animal model. As a prerequisite, we have previously characterized this model at the behavioral and cellular levels and reported major deficits in social activities, gait, and motor coordination. These deficits were directly correlated to the severity of PC loss within the cerebellum .Among the alterations that we found here following prenatal exposure to VPA are (i) slight decreases in the levels of dopamine within the dorsal striatum in females accompanied by (ii) increases in mRNAs coding for the D1 and D2 dopamine receptors within the nucleus accumbens. This suggests that dopamine transmission may be downregulated following VPA prenatal exposure with corresponding upregulation of the two major dopamine receptors. (iii) No alteration was detected in the mRNA and protein levels of several glutamate receptors and subunits. (iv) At the signal transduction level, we report increases in p-mTOR levels in the motor cortex and the cerebellum. (v) We found decreased striatal PV levels in this VPA animal model as also reported in genetic ASD models .Sizable evidence points to a possible dysfunction within the dopamine system that may underlie ASD symptomatology ,35. DopaAlthough consistent, these sets of findings do not allow for determining whether the alterations reported in the dopamine system constitute the molecular and cellular basis of ASD or whether they are merely a consequence of alterations in other systems, which may or may not be related to neuronal transmission. In our hands, and in the VPA mouse model where a single dose of 450 mg/kg VPA was injected at E12.5, we found slight but significant alterations within the dopamine system, indicating a down regulation of dopamine transmission. In addition, we report increased levels of striatal p-mTOR, an integrator of molecular pathways that has been associated with neurodevelopmental, psychiatric, and neurodegenerative disorders including ASD. m-TOR is thought to be an important regulator of striatal functions through an intricate mechanism involving RhoA and as such is considered as a potential therapeutic target . FurtherAs with dopamine, early studies of ASD patients indicated alterations in the glutamatergic system ,19. BlooThe quest to identify molecular targets to ASD is of major importance as no pharmacological management of this neurodevelopmental disorder other than symptomatic is available yet. In accordance with this, our set of results seem to indicate that dopamine and the glutamatergic systems may be only indirectly implicated in the pathophysiology and the subsequent symptomatology of ASD. Given the environmental and genetic heterogeneity of ASD etiologies, a myriad of systems could be potentially affected. These systems may converge towards a cluster of players implicating dopamine and glutamate systems leading to the spectrum of the disease. As such, this does not necessarily translate into alterations of major components of these neurotransmission systems but would rather result in a global disequilibrium away from the physiological homeostasis. If true, the quest for a single regional, cellular, or molecular target to manage all ASD symptoms in all patients might not be fruitful without prior clear identification of the nature of alterations that might be different from one patient to another, in relation with ASD etiology.


Marine biopolymers, abundantly present in seaweeds and marine animals, feature diverse structures and functionalities, and possess a wide range of beneficial biological activities. Characterized by high biocompatibility and biodegradability, as well as unique physicochemical properties, marine biopolymers are attracting a constantly increasing interest for the development of advanced systems for applications in the biomedical field. The development of electrospinning offers an innovative technological platform for the production of nonwoven nanofibrous scaffolds with increased surface area, high encapsulation efficacy, intrinsic interconnectivity, and structural analogy to the natural extracellular matrix. Marine biopolymer-based electrospun nanofibrous scaffolds with multifunctional characteristics and tunable mechanical properties now attract significant attention for biomedical applications, such as tissue engineering, drug delivery, and wound healing. The present review, covering the literature up to the end of 2021, highlights the advancements in the development of marine biopolymer-based electrospun nanofibers for their utilization as cell proliferation scaffolds, bioadhesives, release modifiers, and wound dressings. The marine ecosystem, due to its high biodiversity, represents a plentiful source of bioactive compounds with diverse structures and biological properties ,2. AmongOver the last years, polymeric nanofibers have attracted significant interest in the biomedical sector due to their high surface-to-volume area, high porosity, and tunable mechanical properties ,10,11. EThe incorporation of marine biopolymers —often laThe low electrospinnability of marine biopolymers is also associated with their polyelectrolyte character and high gelation. The spinning solutions of marine biopolymers are usually characterized by high electric conductivity, high viscosity, and high surface tension, which limit their spinning processability. The addition of surfactants—such as Triton-X-100, Pluronic F127, and lecithin—in the spinning solutions is a common strategy to reduce surface tension, increase biopolymer content, and facilitate the production of smooth nanofibers devoid of beads ,22,23. AHerein, marine biopolymers that have been used in the fabrication of electrospun nanofibers are presented, along with their general characteristics and potential for biomedical applications. This review, covering the literature until December 2021, aims to highlight the advancements in the development of electrospun marine biopolymer-based nanofibrous matrices for their application in the biomedical field as drug delivery systems, wound healing materials, and tissue engineering scaffolds.Ascophyllum, Laminaria, Lessonia, and Macrocystis, but can also be isolated from bacteria of the genera Azotobacter and Pseudomonas . I. I56]. Ialbicans . In a si patches .S. aureus and E. coli. The conducted in vivo study on a BALB/C mouse model demonstrated that the nanocomposites accelerated wound healing, providing increased re-epithelialization, collagen deposition, and development of blood vessels and hair follicles  (PLLA). The fibers were fabricated via emulsion electrospinning and revealed a unique beads-in-string structure, with the CA microspheres serving as reservoirs for the encapsulation of the hydrophilic bovine serum albumin (BSA). This microencapsulation technique proved effective for the encapsulation of hydrophilic agents, such as BSA, to achieve prolonged release profiles and low burst-release rates ,7170,71] effects . Recentl effects .S. aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and E. coli, showing great potential for their use as an artificial ECM scaffold  cells, as well as a high proliferation rate, indicating that such alginate nanocomposites could serve as promising candidates for bone regeneration applications . S. S102]. Mandany et al. (2021) investigated the preparation of ulvan/PVA nanofibers from ulvan extracted from micro- or nano-powdered algae with or without organic solvent pretreatment. By using deionized water as a solvent, bead-free fibers were obtained from ulvan samples of non-pretreated algal micropowder, most probably due to their higher molecular weight, whereas intermolecular interactions resulted in bead-free nanofibers with strong mechanical properties for both pretreated and non-pretreated algal nanopowder samples . Madub el-fucose, but they also contain small proportions of uronic acid, galactose, arabinose, mannose, xylose, and glucose . . 208]. RLau et al. (2018) developed artificial nerve-guidance channels from electrospun uniaxially aligned chitosan nanofibers. Chitosan nanofibers were crosslinked with genipin to enhance their structural stability and control their degradation time. Compared to neat chitosan nanofibers, genipin-treated nanofibers displayed enhanced attachment and proliferation of Schwann cells, which are crucial for the survival and function of neurons. The in vitro peripheral nerve regeneration study on dorsal root ganglion explants indicated a remarkable increase in neurite growth along the uniaxially aligned nanofibrous network . ConsideBiocomposite nanofibrous scaffolds for bone regeneration were developed by Zhang et al. (2015), who electrospun a mixture of chitosan, hydroxyapatite, and PHBV. Due to the hydrophobic nature of PHBV, the nanofibrous structure of the matrix remained intact even after 60 days in PBS. Moreover, the presence of hydroxyapatite induced biomineral deposition on the surface of the fibers. The in vitro study showed that the nanofibers enhanced the proliferation of osteoblasts and increased the activity of alkaline phosphatase, suggesting the fabricated biocomposites as promising scaffolds for bone tissue engineering applications B 213]. . 213]. TPorphyromonas gingivalis and Streptococcusmutans, while the incorporation of calcium phosphate enhanced apatite mineralization. The chitosan-based membranes proved to be cytocompatible with BMSCs, showing great potential for guided bone regeneration [Extensive research has been conducted to develop guided bone and tissue regeneration membranes based on chitosan nanofibers for periodontal regeneration ,221,222.neration . RecentlCollagen is a complex polypeptide that represents the most abundant protein in animal and human bodies. It is the main structural component of the ECM in tissues and organs, including skin, bones, tendons, and blood vessels, supporting cell attachment, proliferation, and differentiation ,224. To S. mutans. Moreover, the in vivo experiments for the treatment of furcation defects in dogs revealed that the scaffolds were able to induce bone regeneration [Marine collagen has been broadly investigated for tissue engineering and other biomedical applications due to its low immunogenicity ,227, whineration . In anotneration . For guineration .Jia et al. (2020) demonstrated that electrospun nanofibers of fish collagen blended with PCL could be utilized for cartilage regeneration. The in vitro assessment confirmed the biocompatibility of the nanofibers by promoting chondrocyte proliferation and cartilage formation. Moreover, the in vivo study revealed that the fish collagen/PCL nanofibers induced cartilage regeneration. Increased concentrations of fish collagen worsened the mechanical properties, but resulted in better biodegradability and cell adhesion . In a reGelatin is obtained through denaturation and hydrolytic degradation of collagen. The physicochemical characteristics of gelatin are influenced by the source , collagen type, and manufacturing method. Depending on the treatment of collagen, two types of gelatin can be produced, namely, type A (acid treatment of collagen) and type B . The resulting gelatin is a mixture of fractions varying in size that consists of glycine, proline, and hydroxyproline ,237. OveOver the last years, electrospun nanofibers based on marine gelatin have been developed for various applications. The first fabrication of marine gelatin electrospun nanofibers was reported by Songchotikunpan et al. (2008), who successfully prepared nanofibers from gelatin using either acetic acid or formic acid spinning solutions, investigating the effects of gelatin concentration on the fiber morphology. SEM analyses showed that at higher gelatin concentrations, smooth or mixed smooth and beaded fibers with increased average diameter were obtained . Kwak etE. coli and S. aureus. The nanofibers exhibited improved cytocompatibility and mechanical properties [Composite electrospun nanofibers of fish gelatin reinforced with carboxylated nanodiamonds were developed for bone regeneration applications, triggering biomineralization and improving the adhesion and spread of MG63 osteoblast-like cells . Gomes eoperties .l-iduronic or d-glucuronic acid and d-glucosamine [l-iduronic acid, whereas heparan sulfates are predominantly composed of d-glucuronic acid. Furthermore, the d-glucosamine units of heparins are mainly N-sulfated, while in heparan sulfates they are mainly N-acetylated. Heparins are more sulfated, being produced mainly by mast cells, while heparan sulfates are produced by almost all cell types [Heparins and heparan sulfates are sulfated polysaccharides that belong to the family of GAGs, and are present in the tissues of terrestrial and marine vertebrates and invertebrates. They are linear polysaccharides of complex structures and great heterogeneity, composed of alternating units of highly sulfated cosamine . Heparinll types ,249. Hepll types ,250. Comll types . Over thll types ,252,253.To the best of our knowledge, there are no reports yet on electrospun nanofibers from heparins or heparan sulfates extracted from marine organisms. However, their application in the form of electrospun nanofibrous systems might have great potential, especially considering that electrospun nanofibers based on mammalian heparin have attracted considerable interest as delivery systems and vascular tissue engineering scaffolds ,119. As N-acetyl-galactosamine linked through β-1,3 bonds [Chondroitin sulfates are linear sulfated polysaccharides that belong to the family of GAGs, and are present in the ECM of connective tissues, providing elasticity in the articular cartilage ,255. The,3 bonds . Chondro,3 bonds ,257,258.,3 bonds ,257,259.N-hydroxy succinimide. The crosslinked fiber mats presented enhanced mechanical properties and stability against collagenase degradation. The in vitro study indicated that at low crosslinker concentrations the fiber mats presented adequate cytocompatibility, supporting the proliferation of epithelial cells [Nonetheless, there are limited reports concerning the electrospinning of chondroitin sulfates isolated from marine organisms. Jiang et al. (2019) developed composite nanofibrous scaffolds of either chondroitin sulfate isolated from shark cartilage or rat tail collagen blended with poly(PCL-polytetrahydrofuran urethane) for cartilage regeneration. Both scaffolds promoted the chondrogenesis of bone marrow-derived mesenchymal stem cells and increased the regeneration rate of the injured cartilage, highlighting the chondrogenic potential of marine-derived chondroitin sulfate . In a real cells .N-acetyl-d-glucosamine and d-glucuronic acid linked through β-1,3 and β-1,4 glycosidic bonds, with molecular weights that range between 100 and 100,000 kDa [Hyaluronans, also known as hyaluronic acids, are a group of non-sulfated GAGs present in the ECM of connective tissues in marine and terrestrial animals ,262. The,000 kDa ,263. Ove,000 kDa . Hyaluro,000 kDa ,266,267.P. aeruginosa and S. aureus—probably due to the presence of ε-polylysine. Furthermore, the ocular compatibility study showed that the fiber mats were non-irritant, while being cytocompatible with fibroblasts [Electrospinning of hyaluronans is very challenging due to their high solution viscosity and high surface tension ,268. Altroblasts .Halomonas maura [Mauran is an exopolysaccharide produced by the halophilic bacterium as maura . It is aas maura . Aqueousas maura .To date, only Raveendran et al. (2013) have reported on the electrospinnability of mauran. Electrospun nanofibers of mauran blended with PVA were successfully prepared, with a uniform structure and small average diameter. The biocompatibility of the nanofibers was confirmed in vitro on murine fibroblast cells and mesenchymal stem cells. In cell adhesion studies, the scaffolds were found to promote cell adhesion, migration, proliferation, and differentiation, showing significant potential for tissue engineering and other biomedical applications .Electrospinning offers a versatile technological platform for the production of tailor-made advanced nanostructured systems for various applications in the biomedical field. The broad spectrum of bioactivities exhibited by marine biopolymers renders them ideal candidates for the development of novel nonwoven biomaterials with beneficial functionalities and desired micromechanical properties. Based on the studies highlighted in the present review, it is obvious that electrospun micro/nanofibrous matrices from marine biopolymers have great potential for utilization as biomaterials  for various biomedical applications . In addition to alginates and chitosan, which are extensively studied as marine biopolymers for the fabrication of electrospun biomedical scaffolds, the interest in the electrospinning of other marine biopolymers, such as carrageenans, ulvans, fucoidans, and marine collagen and gelatin, is steadily increasing. Future advancements regarding the electrospinning of marine biopolymers may include the utilization of yet-unexploited marine biopolymers for the production of nonwoven matrices, or in-depth investigation concerning the development of multifunctional fibrous biocomposites. The absence of polymer chain entanglements, the high surface tension, the high gelation, and the poor mechanical properties of marine biopolymers that constrict their utilization into electrospun fibers can be overpassed through chemical modifications, polyelectrolyte complexations, addition of surfactants, crosslinking treatments, coaxial electrospinning, and/or other advanced electrospinning techniques. The use of polymer blends, dispersions, or emulsions of marine biomaterials with synthetic polymers can enhance their electrospinning potential for the development of novel hybrid nanofibrous scaffolds with fascinating properties. The electrospun marine-based nonwovens resulting from the combination of different marine biopolymers with synthetic or other natural polymers can offer the advantageous properties of the chosen materials. Moreover, the incorporation of bioactive ingredients into electrospun marine-based fibers can lead to state-of-the-art multifunctional nanostructured biomaterials for drug delivery, wound healing, and tissue engineering applications.


This review will focus on micromachines and microrobots, which are objects at the micro-level with similar machine functions, as well as nano-level objects such as molecular machines and nanomachines. The paper will initially review recent examples of molecular machines and microrobots that are not limited to interfaces, noting the diversity of their functions. Next, examples of molecular machines and micromachines/micro-robots functioning at the air-water interface will be discussed. The behaviors of molecular machines are influenced significantly by the specific characteristics of the air-water interface. By placing molecular machines at the air-water interface, the scientific horizon and depth of molecular machine research will increase dramatically. On the other hand, for microrobotics, more practical and advanced systems have been reported, such as the development of microrobots and microswimmers for environmental remediations and biomedical applications. The research currently being conducted on the surface of water may provide significant basic knowledge for future practical uses of molecular machines and microrobots. The development of mankind depends on the exploration of new functional materials. In particular, it has been supported over the last century by the development of various research fields related to materials development, including organic chemistry ,2,3,4, iNanoarchitectonics combines various processes from basic units such as atoms, molecules, and nanomaterials to architect functional material systems. It selects and combines methods such as manipulation at the atomic/molecular level, material transformation through chemical reactions and physical phenomena, self-assembly and self-organization, sequencing and ordering through external fields and manipulations, fabrication at the nano- and micro-levels, and biospecific methods to create functional materials . CompareThus, nanoarchitectonics shares values with existing fields of science and technology. Therefore, some of the existing research may not be usually called nanoarchitectonics, but may take a similar approach. In particular, functional materials are currently being developed based on nanostructure control, including various supramolecular assemblies, complex structure formation, and polymer alignment. In some of these examples, we can find important elements of nanoarchitectonics. Tohnai et al. have performed structural nanoarchitectonics of functional organic molecules in solids . Using oAs seen in the above-mentioned examples, nanoarchitectonics and its related chemistry, such as supramolecular chemistry, have made significant achievements in functional materials systems. However, since nanoarchitectonics is based on nanotechnology, it is also powerful in the fabrication and functional development at much smaller levels. For example, in a technique known as local probe chemistry, the tip of a probe microscope can be used to carry a reactive molecule to a peep site and cause a substitution reaction ,102. NanNanoarchitectonics produces functional systems of various sizes based on nano-level phenomena. Nano-level phenomena often have effects of ambiguities such as thermal fluctuations, stochastic distributions, and quantum effects. Therefore, nanoarchitectonics can be considered to harmonize effects including ambiguities rather than the sum of their respective effects . In partFrom the above perspective, this review paper will focus on micromachines and microrobots ,118, whiThe development of molecular machines and similar functional molecules is extensively researched. It is virtually impossible to present an exhaustive list of all examples. Here, a few recent examples are given to illustrate the breadth of the developments.Molecular geometry plays an important role in the mechanical functioning of molecules. Tokunaga, Tahara, and co-workers present a theoretical consideration of the molecular geometry required for quantum dot cellular automata . They shDirect evaluation of the mechanical motion of molecular machines has also been done. The donor-acceptor π interaction is often used in supramolecular and molecular machine design. In addition to interpreting these interactions in terms of energies obtained at thermodynamic equilibrium, evaluation of the mechanical strength of processes out of equilibrium is also necessary for implementing synthetic molecular machines. Sluysmans et al. used single molecule force microscopy to determine the non-equilibrium mechanical strength of individual donor-acceptor π interactions . As showZhang, Hong, Chen, and co-workers evaluated the internal dynamics of rotation in molecular machines at the single-molecule scale  125]. T. T125]. Molecular recognition is a key in functional systems such as molecular machines and molecular sensors ,127,128.As a molecular nanoarchitectonics approach conducive to molecular machine design, Zhang, Zhu, and co-workers demonstrated a controlled creation of radial [n]catenanes as molecular necklaces  131]. T. T131]. Architecting individual molecular motors and molecular switch-like functions into larger metafunctional systems is an important step in the study of molecular machines. Grill and Dube relayed the light-induced shape changes of a hemithioindigo-based molecular motor to the catalytic efficiency of a chemical reaction . They reII-mediated base pairs (H-CuII-H) and logic gate control was reported  and magnetic material (Fe3O4). These microrobots are self-propelled under sunlight and can be moved precisely by magnetic fields in microchannels. The localized self-stirring effect at the nanoscale allows them to efficiently degrade a variety of synthetic microplastics such as polylactic acid and polycaprolactone. In other words, this photocatalytic microrobot does not require a mechanical stirring device, which is typically required.Light-driven microrobots based on organic semiconductors have attracted much attention in the past few years. Pumera and co-workers have developed a tubular inorganic/organic hybrid that combines mesoporous silica with active polymers containing thiophene and triazine units as photoactive microrobots  158]. T. T158]. 3O4 magnetic nanoparticles . U. U160]. articles . This miThe ability to change its shape and size is also a useful property in the design of highly functional microrobots. In particular, more complex drug delivery operations such as drug encapsulation and release in practical biological applications also require that microrobots have shape adaptability to dynamic environments. Li, Zhang, Wu, and co-workers developed an environmentally adaptive shape-shifting micro architectural means to programmatically code different expansion rates into a pH-responsive hydrogel for robot development  162]. C. C162]. The role of interfaces in molecular machine and microrobotics research is significant. In particular, direct observation and evaluation of nanomachines such as molecular machines and nanocars are now being performed in detail on solid substrates. Although it is difficult to conduct advanced research such as observation at the molecular level at the liquid interface, which is a softer and more fluctuating environment as an interface, it has the potential to bring out the dynamic properties of molecular machines. In particular, the interface with water (air-water interface), which is common to biological systems, can be a new frontier for the study of molecular machines.The air-water interface is also known as a field where excellent molecular recognition properties are achieved through hydrogen bonding, despite the presence of water . Hydroge2 of molecular occupied area. It was found that the steroidal cyclophane molecules formed a three-dimensional cavity and grabbed the guest molecules present in the water. Macroscopic repetition of compression and expansion of the monolayer at the level of tens of centimeters was found to cause a corresponding repetitive catch and release of the guest molecules. Using the molecular machine at the air-water interfacial environment, a bulk mechanical stimulus  that can be moved by hand can grab and release molecules that are at the nanoscale.Manual actuation of a molecular machine using the steroid cyclophane at the air-water interface was investigated  170,171171. ThisA more delicate structural control is the mechanical tuning of molecular receptors. For example, the molecular receptor cholesterol-armed cyclen is a molecule that can produce a chiral twist, and its chiral environment allows it to selectively adsorb chiral molecules . This moThe above examples change the way we think about molecular recognition. −1, about 0.2 kcal mol−1 of mechanical energy is stored, and about the same value of molecular deformation energy is used. At higher pressures, the molecular deformation energy is smaller than the mechanical energy, but the results suggest that macroscopic mechanical energy can be used very efficiently to deform molecular machines in interfacial systems.In addition, a simpler molecular machine was used to quantitatively analyze molecular deformation at the interface A 184]. . 184]. HMolecules with hydrophilic and hydrophobic portions have been studied as molecular pliers, and it was clear that the dihedral angle changes continuously and analogously in response to mechanical stimuli applied externally. However, it was a molecular deformation with unchanged helicity, cisoid-to-cisoid. Using a system of simpler, more crystalline binaphthyl molecules dispersed in a matrix, a cisoid-to-transoid (closed-to-open) asymmetric control with a change in helicity (right-handed to left-handed or vice versa) was successfully B 185]. . 185]. TŻywociński, Hołyst, and co-workers measured the frequency of collective molecular precession as a function of temperature in ferroelectric liquid crystal monolayers at the air-water interface . This prThe behavior of molecular machines such as molecular rotors at the air-water interface and in thin films is affected by the surrounding environment, such as coexisting monolayer materials and surface pressure. Mori et al. investigated the rotational behavior of a twisted intramolecular charge transfer-type 9-(2-carboxy-2-cyanovinyl)julolidine derivative as a molecular rotor by in situ fluorescence spectroscopy  188]. M. M188]. Saito and co-workers have developed a series of hybrid π-conjugated molecules that combine the advantages of rigidity with flexibility, based on the viewpoint of moving the π-conjugated backbone. The result is a series of hybrid π-conjugated molecules that have the advantage of flexibility while taking advantage of rigidity. These molecules are named as FLAP  ,191. NakComparing the same molecule or molecular machine in various interfacial environments is also an interesting research target. The behavior of bisbinaphthyldurene molecules, considered as nanocar molecules on a solid surface under ultrahigh vacuum and cryogenic conditions , was invNaota and co-workers have very recently studied the chirality and magnitude of circularly polarized luminescence of trans-bisplatinum(II) complexes by using a mechanical rotational stimulation method at the air-water interface . The chiAdachi et al. developed a new principle of “submarine emission,” in which a double-paddle platinum complex is used to control the luminescence of cyclic amphiphilic molecules at the air-water interface by means of mechanical manipulation  199]. W. W199]. As seen in the above examples, the air-water interface is a field where the dielectric constant varies greatly at the molecular level, with properties such as an overwhelming difference in magnitude between the film surface direction and the film thickness pressure direction, high fluidity and dynamism. Placing molecular machines, which are molecular-level objects, at these interfaces generates various scientifically innovative research. On the other hand, the molecular size properties of the air-water interface might not have a significant influence on larger microrobots. However, the surface of water is a place where molecular robots can move freely, and a variety of research is being conducted. In particular, many of the studies on microrobots are aimed at practical applications in aqueous environments. Here, the following part lists a few examples to illustrate the diversity of their functions at the air-water interface.Superhydrophobic microrobots can swim efficiently and rapidly on water by external stimuli and have attracted great research interest for various applications. Jiao, Liu, and coworkers have developed a multi-stimulus-responsive superhydrophobic microrobot that can drift at high speed on water through optical, magnetic, and chemical controls  201]. T. T201]. The development of hybrid microrobots capable of both terrestrial and underwater activities requires harmonizing and reconciling different behaviors and various constraints in different environments. Chen, Wood, and co-workers have developed a quadruped microrobot that can walk on land, swim in water, and transition between the two . The mico rotational jump. These multiple capabilities overcome the disadvantages of microrobots with a single mode of locomotion.Light-responsive superhydrophobic microrobots based on the Marangoni effect have attracted much attention, and Jiao, Liu, and co-workers have fabricated graphene/polydimethylsiloxane composite materials that exhibit excellent superhydrophobicity and photothermal properties . Using t2O2 solutions. However, this mechanism should be applicable to various solution systems if bubbles can be generated by other reactions. For example, it could be used in the human body for drug delivery in acidic environments such as the stomach.Zheng, Cui, and co-workers have developed a remotely operated bubble microrobot with multiple modes of operation and high maneuverability at the air-liquid interface  205]. T. T205]. Microrobots that operate on liquid surfaces have great potential for micromanipulation in confined spaces and confined locations. In particular, contraptions that produce agile and functional microrobots with simple structures are desired. Wang and co-workers reported a pair of magnetic microdiscs that work as partners  206]. T. T206]. Bryan et al. fabricated microswimmers by photolithography and electrodeposition using Co-Ni-P magnetic nanoparticles consisting of elastically and magnetically coupled hard Co-Ni-P and soft Co ferromagnets . The selThis review paper overviews several recent examples of research on molecular machines and microrobots, which are small objects that work in a variety of modalities. These, like machines in our macroscopic world, are important in how they architect their functional structures. Therefore, methodological approaches such as nanoarchitectonics and microfabrication will determine the performance of these tiny machines. This is the subject where nanoarchitectonics can show its true value.These small machines, especially molecular machines, have been studied mainly for their work in solution and on solid surfaces. In this review paper, it is examined that the results obtained when the working field of these tiny machines is moved from these usual fields to the water surface. The behaviors of molecular machines are influenced significantly by the following characteristics of the air-water interface: (i) it is a phase boundary with different dielectric constants at the molecular level, (ii) the size spread is extremely different between the film lateral direction and the film thickness direction, (iii) it has a very high degree of freedom of motion compared to solid surfaces, (iv) collective behavior of aggregated molecules can occur, and so on. By placing molecular machines at the air-water interface, the scientific horizon and depth of molecular machine research will increase dramatically. In the field of microrobotics, more practical and advanced systems have been reported, such as the development of microrobots that act like swimming on the water surface (microswimmer), behave on the water surface like water striders and insects, and can transition between water, the water surface, and solid surfaces. These advanced examples of microrobots can be seen as examples of research that molecular machines will follow. It is expected that similar advanced systems that are close to practical use will be realized in molecular machines. The air-water interface and the thin films created at the interface can be used as simplified models of biological membranes and cell surfaces. The research currently being conducted on the surface of water may provide significant basic knowledge for practical use in cells. In fact, examples of molecular motors that work by acting on cell membranes have been reported.Mankind is tackling the challenges it faces in energy ,210,211,


The objective was to retrospectively develop a protocol in swine for optimal contrast media timing in coronary CT angiography (CCTA).Several dynamic acquisitions were performed in 28 swine (55 ± 24 kg) with cardiac outputs between 1.5 and 5.5 L/min, for 80 total acquisitions. The contrast was injected , followed by dynamic scanning of the entire aortic enhancement curve, from which the true peak time and aortic and coronary enhancements were recorded as the reference standard. Each dataset was then used to simulate two different CCTA protocols—a new optimal protocol and a standard clinical protocol. For the optimal protocol, the CCTA was acquired after bolus tracking-based trigging using a variable time delay of one-half the contrast injection time interval plus 1.5 s. For the standard protocol, the CCTA was acquired after bolus tracking-based triggering using a fixed time delay of 5 s. For both protocols, the CCTA time, aortic enhancement, coronary enhancement, and coronary contrast-to-noise ratio (CNR) were quantitatively compared to the reference standard measurements.For the optimal protocol, the angiogram was acquired within −0.15 ± 0.75 s of the true peak time, for a mean coronary CNR within 7% of the peak coronary CNR. Conversely, for the standard CCTA protocol, the angiogram was acquired within −1.82 ± 1.71 s of the true peak time, for a mean coronary CNR that was 23% lower than the peak coronary CNR.The optimal CCTA protocol improves contrast media timing and coronary CNR by acquiring the angiogram at the true aortic root peak time.This study in swine retrospectively developed the mathematical basis of an improved approach for optimal contrast media timing in CCTA.• By combining dynamic bolus tracking with a simple contrast injection timing relation, CCTA can be acquired at the peak of the aortic root enhancement.• CCTA acquisition at the peak of the aortic root enhancement should maximize the coronary enhancement and CNR, potentially improving the accuracy of CT-based assessment of coronary artery disease.• The online version contains supplementary material available at 10.1007/s00330-022-09161-z. Coronary computed tomography angiography (CCTA) is a powerful tool for noninvasive assessment of coronary artery disease, where plaque burden and stenosis severity are highly predictive of major adverse cardiac events . In partRegarding contrast timing, the accuracy of CCTA depends directly upon the coronary enhancement , 6. WhilThus, the objective of this study was to retrospectively develop a CCTA protocol in swine for optimal contrast media timing with improved coronary enhancement, where a standard clinical CCTA protocol was also employed for comparison The optimal protocol combines 2-mm slice dynamic bolus tracking with a variable acquisition delay following triggering, where this delay—equal to one-half the contrast injection time interval plus a fixed dispersion time –14—enablData acquisition: Several dynamic acquisitions were conducted per animal under rest and stress conditions, as previously reported  and discModelling: The aortic contrast bolus geometry of each acquisition was characterized using automatic gamma variate fitting, where the true aortic peak time, aortic enhancement, coronary enhancement, and coronary contrast-to-noise ratio (CNR) were recorded as the reference standard.Protocol simulation: The model fit curves of each acquisition were used retrospectively to simulate the optimal CCTA protocol as well as a standard clinical CCTA protocol for comparison. For each protocol, the CCTA acquisition time, aortic enhancement, coronary enhancement, and coronary CNR were compared to the reference standard measurements.The study was approved by the Institutional Animal Care and Use Committee and was performed using data that were previously acquired from 28 male Yorkshire swine (55 ± 24 kg) , where t®, Cordis Corporation) in each femoral vein and were used for contrast media injection, intravenous fluids, and adenosine administration.Induction of anesthesia was achieved with Telazol (4.4 mg/kg), Ketamine (2.2 mg/kg), and Xylazine (2.2 mg/kg), and was maintained with 1.5–2.5% Isoflurane  . IntroduFor the 28 animals assessed, approximately half underwent one rest and one stress acquisition , while the other half underwent two rest and two stress acquisitions , where stress was used  to modulate cardiac output . For eacFor each acquisition series, the central lumen of the aortic root was segmented semi-automatically , to yield a 5 mL vascular volume-of-interest (VOI). This VOI was used to generate an enhancement curve that was automatically fit with a gamma variate function  , as showA is the maximum enhancement, t is time, τ is the peak time, B is the growth factor, and C is the initial pre-contrast blood pool enhancement. The resulting fit curves were then used to identify the volume scan at the aortic root peak, after which the reference aortic root enhancement, coronary enhancement, and coronary CNR were determined. Specifically, the aortic VOI was used to measure the mean and standard deviation of the aortic root enhancement. Next, volumetric segments of the proximal left main (LM) and right coronary (RCA) arterial lumens were segmented semiautomatically , to measure the mean coronary enhancements. Finally, the CNR of the LM and RCA were calculated as the mean coronary enhancement minus the surrounding tissue enhancement normalized by the standard deviation of the aortic root enhancement. Finally, each aortic fit curve was used to simulate the optimal and standard CCTA protocols.Td) corresponds to the trigger-to-peak enhancement time of the bolus (TTTP), as shown in Eq. During contrast injection, the bolus enters the venous blood pool at a high rate, remaining largely unmixed over the injection duration, as displayed in Fig. entclass1pt{minimaHence, the optimal CCTA protocol applied this peak timing theory to the aortic fit curves. First, 2-mm slice dynamic bolus tracking was simulated with triggering at 150 HU in the aortic root to emulate clinical practice. Following triggering, a variable time delay of one-half the contrast injection duration plus a dispersion delay of 1.5 s was employed for all animals, after which the first available ECG-gated volume scan was “acquired” as the CCTA, as shown in Fig. Using the same aortic fit curves, 2-mm slice dynamic bolus tracking was again simulated with triggering at 150 HU in the aortic root as above. Following triggering, a fixed time delay of 5 s was employed, after which the first available ECG-gated volume scan was “acquired” as the standard clinical CCTA, as shown in Fig. p < 0.05), where the errors of such measurements were also computed. Second, the trigger-to-acquisition time and aortic enhancement of both the optimal and standard CCTA protocols were compared to the reference standard through regression, where Pearson’s correlation (r) and root-mean-square-error (RMSE) of measurement were also determined. Finally, the trigger-to-acquisition time error and aortic enhancement error of both the optimal and standard CCTA protocols as a function of contrast injection time were assessed through regression, where Pearson’s correlation (r) and root-mean-square-error (RMSE) of measurement were also computed. Statistical software was used for all analyses .As our prior work found no significant differences in bolus time-to-peak between rest and stress , all resA total of 80 acquisitions were completed in the 28 swine with cardiac outputs ranging from 1.5 to 5.5 L/min. The weight-based contrast media injection volumes ranged from 27 to 95 mL, corresponding to the 55 ± 24 kg weights of the animals, while the contrast media injection times, excluding the saline chaser, ranged from 5.4 to 19.0 s (given the fixed 5 mL/s rate of injection).The mean trigger-to-acquisition times of the optimal and standard CCTA protocols were 7.04 ± 1.49 and 5.37 ± 0.21 s, respectively, while the corresponding trigger-to-reference peak time was 7.19 ± 1.68 s. Moreover, the mean aortic enhancements of the optimal and standard CCTA protocols were 770.54 ± 135.30 and 727.31 ± 143.12 HU, respectively, while the corresponding reference aortic enhancement was 787.07 ± 142.39 HU. Likewise, the mean combined coronary enhancements (LM and RCA) of the optimal and standard CCTA protocols were 455.64 ± 182.34 and 421.39 ± 170.10 HU, respectively, while the corresponding reference coronary enhancement was 487.57 ± 179.52. Finally, the mean combined coronary CNR (LM and RCA) of the optimal and standard CCTA protocols were 9.69 ± 6.62 and 8.18 ± 6.09 HU: approximately 7% and 23% lower than the corresponding reference CNR of 10.64 ± 6.41, respectively. The above data, individual coronary data, and the corresponding t-testing and error analysis are detailed in Table TACQ) of the optimal CCTA protocol to the trigger-to-reference peak time (TPEAK), the data were related through regression by TACQ = 0.79 TPEAK + 1.40, with a Pearson’s correlation of 0.90 and a RMSE of 0.74 s. When comparing the trigger-to-acquisition time (TACQ) of the standard CCTA protocol to the trigger-to-reference peak time (TPEAK), the data were related through regression by TACQ = −0.01 TPEAK + 5.42, with a Pearson’s correlation of 0.07 and a RMSE of 2.50 s, as shown in Fig. ACQ) of the optimal CCTA protocol to the reference aortic enhancement (HUPEAK), the data were related through regression by HUACQ = 0.95 HUPEAK + 29.08, with a Pearson’s correlation of 1.00 and RMSE of 19.34 HU. When comparing the aortic enhancement (HUACQ) of the standard CCTA protocol to the reference aortic enhancement (HUPEAK), the data were related through regression by HUACQ = 0.88 HUPEAK + 30.69, with a Pearson’s correlation of 0.94 and a RMSE or 72.73 HU, as shown in Fig. When comparing the trigger-to-acquisition time (TERR) of the optimal CCTA protocol as a function of contrast injection time (TINJ), the data were related through regression by TERR = −0.02 TINJ + 0.13, with a Pearson’s correlation of 0.10 and a RMSE of 0.74 s. When assessing the trigger-to-acquisition time error (TERR) of the standard CCTA protocol as a function of contrast injection time (TINJ), the data were related through regression by TERR = −0.52 TINJ + 3.56, with a Pearson’s correlation of 0.90 and a RMSE of 2.51 s, as shown in Fig. ERR) of the optimal CCTA protocol as a function of contrast injection time (TINJ), the data were related through regression by HUERR = 0.70 TINJ −16.53, with a Pearson’s correlation of 0.32 and a RMSE of 19.34 HU. When assessing the aortic enhancement error (HUERR) of the standard CCTA protocol as a function of contrast injection time (TINJ) the data were related through regression by HUERR = −10.78 TINJ + 61.08, with a Pearson’s correlation of 0.90 and a RMSE of 72.73 HU, as shown in Fig. When assessing the trigger-to-acquisition time error , future work should still employ larger animals with significant disease using a more peripheral injection site, where different injection volumes and rates should be assessed for more robust validation of the protocol. Finally, future work should employ half-projection scanning or reconstruction to minimize gantry-rotation-induced motion artifacts, while trained readers could also be used for quality assessment scoring .This study in swine retrospectively developed the mathematical basis of an improved approach for optimal contrast media timing in CCTA. Specifically, by combining dynamic bolus tracking with a simple contrast injection timing relation, reliable timing of the angiogram at the true peak of the aortic root enhancement is feasible. As a result, coronary enhancement and contrast-to-noise ratio should be maximized, potentially improving the accuracy of CT-based assessment of coronary artery disease.ESM 1(DOCX 492 kb)