bluuebunny/crossref_metadata_2025 huggingface dataset:
A robust, low-voltage driven millirobot based on transparent ferroelectric crystals
Authors: Gao Xiangyu , Qiao Liao , Qiu Chaorui , Wang Ting , Zhang Lin , Liu Jinfeng , Yang Shuai , Jin Haonan , Xin Benjian , Zhang Shujun , Dong Shuxiang , Xu Zhuo , Li Fei
Published: January 2022

Low driving voltage is important for miniaturization and untethered service of millirobots made of piezoelectric materials. In this research, we designed a bio-inspired bimorph-structured millirobot with a transparent relaxor ferroelectric crystal. Due to the ultrahigh piezoelectricity of the relaxor ferroelectric crystals and the optimized bimorph-based structure, the millirobot shows a maximum moving speed up to 9.22 b s−1 (body length per second) at 100 V, while the minimum driving voltage for initial movement can be as low as 3 V, which is more than two orders of magnitude smaller than that of millirobot based on dielectric elastomers. The maximum and minimum power consumptions of the millirobot are 71.6 mW and 85.9 μW, respectively. The robustness of the millirobot is reflected in its mechanical load stability carrying a 78 g mass (97.5 times of its weight) and its cryogenic tolerance. This work is believed to be beneficial to the design of various robust electromechanical devices with low driving voltage.
On Jutila's integral in the circle problem
Authors: Korolev Maxim Aleksandrovich , Popov Dmitrii Aleksandrovich
Published: January 2022

We study a ‘correlation’ function $\mathcal{K}_{P} = \mathcal{K}_{P}(T;H,U)$ of the error term
$P(t)$ in the circle problem, that is, the integral of the product
$P(t)P(t+U)$ over the interval $(T,T+H]$, $1 ė U, H ė T$.
The case of small $U$, $1\le U\ll \sqrt{T}$, was in essence studied by Jutila in 1984.
It turns out that, for all these $U$ and sufficiently large $H$,
$\mathcal{K}_{P}$ attains its maximum possible value. In this paper we study the case
of ‘large’ $U$, $\sqrt{T}\ll U\le T$, when the behaviour of $\mathcal{K}_{P}$ becomes more
complicated. In particular, we prove that the correlation function may be positive and negative
of maximally large modulus as well as having very small modulus on sets of values of $U$
of positive measure.
Configuration spaces of hinged mechanisms, and their projections
Authors: Kovalev M. D.
Published: January 2022

Our subject is the geometry of planar hinged mechanisms. The article contains a formalization of basic concepts of the theory of hinged-lever constructions, as well as some information from real algebraic geometry needed for their study. We consider mechanisms with variable number of degrees of freedom and mechanisms that have more than one degree of freedom but each hinge of which moves with one degree of freedom. For the last type we find the dimension of the configuration space. We give a number of examples of mechanisms with unusual geometric properties and formulate open questions.

Bibliography: 17 titles.
Broadcasting of amplitude- and frequency-modulated c-di-GMP signals facilitates cooperative surface commitment in bacterial lineages
Authors: Lee Calvin K. , Schmidt William C. , Webster Shanice S. , Chen Jonathan W. , O’Toole George A. , Wong Gerard C. L.
Published: January 2022

Significance

It is well known that c-di-GMP concentration rises in surface-sensing bacteria and functions as a “molecular switch” for biofilm formation. Here, we provide an important recasting of this picture: Intracellular c-di-GMP signals do not just increase in surface-sensing bacteria; such signals are cooperatively broadcast across multiple generations of cells in a lineage with oscillations that undergo both amplitude and frequency modulation, which are controlled by the coupling between pili appendages and c-di-GMP synthesis machinery. The right “tuning” of these signals in terms of frequency and amplitude correlates ultimately to surface commitment. Amplitude and frequency modulation of c-di-GMP signals allows encoding of more complex instructions. Thus, our work provides a more nuanced understanding of how c-di-GMP signaling drives surface commitment.
The context of the ribosome binding site in mRNAs defines specificity of action of kasugamycin, an inhibitor of translation initiation
Authors: Zhang Yan , Aleksashin Nikolay A. , Klepacki Dorota , Anderson Caleb , Vázquez-Laslop Nora , Gross Carol A. , Mankin Alexander S.
Published: January 2022

Significance

Several antibiotics targeting the large ribosomal subunit interfere with translation in a context-specific manner, preventing ribosomes from polymerizing specific amino acid sequences. Here, we reveal kasugamycin as a small ribosomal subunit-targeting antibiotic whose action depends on the sequence context of the untranslated messenger RNA (mRNA) segments. We show that kasugamycin-induced ribosomal arrest at the start codons of the genes and the resulting inhibition of gene expression depend on the nature of the mRNA nucleotide immediately preceding the start codon and on the proximity of the stop codon of the upstream cistron. Our findings underlie the importance of mRNA context for the action of protein synthesis inhibitors and might help to guide the development of better antibiotics.
Liquid polarity, positional contrast, and diachronic change
Authors: Sen Ranjan , Zair Nicholas
Published: January 2022

Apparently disparate sound changes in Latin, involving both vowels and consonants but sensitive to /r/, can be explained by reconstructing a positional clear/dark contrast in /r/, motivated by the seldom-mentioned “liquid polarity” effect. Examining these diachronic processes together allows us to see a larger picture, providing evidence for the reconstruction of successive past synchronic states. Latin /r/ mirrored the behaviour of Latin /l/ up to the first century BC: /l/ was dark and /r/ was clear in codas, and /r/ was dark and /l/ was underspecified for tongue body position in onsets. Darkness in /r/ was partly implemented through the selection of r-type: dark onset approximant and clear coda tap. Later, coda /r/ became an approximant like onset /r/, and subsequently both became trills, resulting in the erosion of the positional contrast and the liquid polarity effect.
On the conditional marker “zhě”(者)
Authors: Li Fanxi
Published: January 2022

This paper aims to explain the development of “zhě” serving as a conditional marker mainly in Late Archaic Chinese and to show that the conditional marker “zhě” derives from the nominalizer “zhě”. The grammaticalization of “zhě” is at the level of pragmatic inference, which shows an interaction of nominalization, topicality, and conditionality. Nominalization directly makes the original clause lose its ability to confirm the factuality of the event, and the nominalized construction then is endowed with a generic meaning, which is in some way related to conditionals. Specifically, the contexts triggering this grammaticalization can be summarized as follows: Firstly, the construction “VP/clause + zhě” always occupies the topic position; secondly, VPs/clauses in that construction always represent a kind of non-factual event, which means that the semantic feature of the VPs/clauses is non-factual or unreal. Furthermore, there are two clues, namely modal auxiliary and negator, which can help identify the non-factual event.
Language policy and planning for English-medium instruction in higher education
Authors: Ou Amy Wanyu , Hult Francis M. , Gu Michelle Mingyue
Published: January 2022

This article presents English-medium instruction (EMI) in higher education (HE) from a language policy and planning (LPP) perspective. Based on a review of EMI policy research in diverse higher education contexts, we address several key contemporary policy tensions in EMI such as English native-speakerism, English monolingualism, and language education with attention to corpus, status and acquisition planning as well as the role of individual policy actors. In light of this review, we argue for an orientation to policymaking for EMI-HE institutions that acknowledges the value of individuals as policy arbiters and aligns institutional goals with “on the ground” needs and practices. We also point to areas of future research that would benefit all EMI stakeholders, in particular critical engagement with the nature of language competence in EMI settings and the enhanced development of evidence-based EMI learning outcomes. Finally, we propose an ecological framework for EMI-HE policy development that could be employed as a heuristic to guide universities in designing concrete EMI policies for their local contexts. As an extension, we also offer an inventory of reflective questions to guide key university stakeholders in effectively engaging in EMI policy processes.
Single-cell immune profiling reveals functional diversity of T cells in tuberculous pleural effusion
Authors: Cai Yi , Wang Yejun , Shi Chenyan , Dai Youchao , Li Fuxiang , Xu Yuzhong , Zhang Peize , Kong Fanhui , Deng Guofang , Wen Zhihua , Zhou Qi , Kang Boxi Chris , Singhal Amit , Yang Qianting , Feng Carl G. , Chen Xinchun
Published: January 2022

Orchestration of an effective T lymphocyte response at infection sites is critical for protection against Mycobacterium tuberculosis (Mtb) infection. However, the local T cell immunity landscape in human tuberculosis is poorly defined. Tuberculous pleural effusion (TPE), caused by Mtb, is characterized by an influx of leukocytes to the pleural space, providing a platform suitable for delineating complex tissue responses to Mtb infection. Using single-cell transcriptomics and T cell receptor sequencing, we analyzed mononuclear cell populations in paired pleural fluid and peripheral blood of TPE patients. While all major cell clusters were present in both tissues, their relative proportions varied significantly by anatomic location. Lineage tracking analysis revealed subsets of CD8 and CD4 T cell populations with distinct effector functions specifically expanded at pleural sites. Granzyme K–expressing CD8 T cells were preferentially enriched and clonally expanded in pleural fluid from TPE, suggesting that they are involved in the pathogenesis of the disease. The findings collectively reveal the landscape of local T cell immunity in tuberculosis.
The effects of Ti3C2 MXene additive on lithiation induced stress in silicon/graphite-based electrodes for lithium ion batteries
Authors: Wang Zhuo , Liu Jishan , Chen Kongyao , Wu Xueling , Mi Liwei , Mao Weiguo
Published: January 2022

The lithiation induced stress in multilayer silicon/graphite-based electrodes for lithium ion batteries is evaluated analytically. Firstly, the silicon/graphite-based composite active layer is reinforced by Ti3C2 MXene, and the effects of Ti3C2 MXene additive on elastic modulus of the active layer are discussed based on the Halpin–Tsai empirical equation. Secondly, biaxial stresses in both bilayer and symmetric trilayer silicon/graphite-based electrodes are estimated by a mechano-electrochemical model, which is derived by imitating thermal expansion stress in layered structural components. And the effects of Ti3C2 MXene’s parameters, including additive amount, number of layers and length–width ratio, on the stress in multilayer silicon/graphite-based electrodes are also be discussed in detail. Finally, based on the numerical analysis, some design strategies for Ti3C2 MXene reinforced composite active layer are proposed from mechanical views.
Effective field theory analysis of 3He–α scattering data
Authors: Poudel Maheshwor , Phillips Daniel R
Published: January 2022

We treat low-energy 3He–α elastic scattering in an effective field theory (EFT) that exploits the separation of scales in this reaction. We compute the amplitude up to next-to-next-to-leading order, developing a hierarchy of the effective-range parameters (ERPs) that contribute at various orders. We use the resulting formalism to analyse data for recent measurements at center-of-mass energies of 0.38–3.12 MeV using the scattering of nuclei in inverse kinematics (SONIK) gas target at TRIUMF as well as older data in this energy regime. We employ a likelihood function that incorporates the theoretical uncertainty due to truncation of the EFT and use Markov chain Monte Carlo sampling to obtain the resulting posterior probability distribution. We find that the inclusion of a small amount of data on the analysing power A

y
is crucial to determine the sign of the p-wave splitting in such an analysis. The combination of A

y
and SONIK data constrains all ERPs up to O(p
4) in both s- and p-waves quite well. The asymptotic normalisation coefficients and s-wave scattering length are consistent with a recent EFT analysis of the capture reaction 3He(α, γ)7Be.
XPS binding energy shifts as a function of bond distances: a case study of CO
Authors: Bagus Paul S , Sousa Carmen , Illas Francesc
Published: January 2022

The O(1s) and C(1s) XPS core-level binding energies. BEs, have been studied as a function of the C–O internuclear distance for a large range of distances. The BE(r) for both BEs show considerable variation over the distances studied which is, however, different for the O(1s) and C(1s) BEs. The origin of the dependence on C–O distance is established and shown to involve more than the electric field generated because of the charge separation within CO being C+q
and O−q
. Furthermore, the BE(r) is shown to be different for Hartree–Fock and correlated wavefunctions indicating that the BE(r) can provide evidence of how electron correlation modifies the valence charge distribution. The difference between the O(1s) and C(1s) BEs is examined and it is proposed that this difference can be used as a measure of the accuracy of theoretically predicted BEs. It is believed that the features found for CO may be representative for the BE variations with geometry for other systems; an effect that has been mostly overlooked.
Illustrating dimensionless scaling with Hooke’s law
Authors: Bissell J J , Ali A , Postle B J
Published: January 2022

Dimensionless variables and scalings are powerful tools for emphasising the universality of natural laws, but their application is typically restricted to topics in advanced physics. Here we describe how dimensionless scaling can be illustrated in an introductory physics context by considering a dimensionless form for Hooke’s law. As a simple empirical study, we verify this form for Hooke’s law using data from foundation-year degree (high-school level) experiments on springs in series and parallel.
Flexural properties of lightweight carbon fiber/epoxy resin composite sandwiches with different fiber directions
Authors: Liu J A , Dong Z Q , Zhu X Y , Sun W B , Huang Z Q
Published: January 2022

In this study, structurally efficient carbon fiber reinforced plastic (CFRP) sandwiches were developed via introducing pumice/Mg composite foams as new core material. The effects of the fiber direction (0°, 45°, 90°) on the mechanical properties of CFRP laminates and composite sandwiches were studied. Compared with 45°-CFRP and 90°-CFRP laminates, 0°-CFRP laminate exhibits outstanding flexural properties due to different failure modes. Correspondingly, the 0°-CFRP/PMSF composite sandwiches exhibit higher flexural strength than 45°-CFRP/PMSF and 90°-CFRP/PMSF composite sandwiches. The as-prepared composite sandwiches are lightweight and have higher specific strength than some traditional sandwiches. The different flexural behaviors of three types of sandwiches were observed to explain the failure mechanisms.
Induction heating ferromagnetic particles embedded PDMS mold for microstructure embossing
Authors: Hsu Ming-Huai , Tsai Yao-Yang , Yang Sen-Yeu
Published: January 2022

Polydimethylsiloxane (PDMS) is an excellent soft mold material with the advantages of precise replication, easy demolding, and low production cost. However, the strength and hardness of PDMS are relatively low, and PDMS cannot be directly inductively heated. In this study, PDMS is embedded with ferromagnetic powders to increase its hardness and make it heatable. Direct induction heating of the PDMS mold can raise its inherent temperature, increase the heating efficiency by 100% compared with pure PDMS, and improve the shortcomings of uneven surface temperature distribution from high thermal resistance. Furthermore, adding the ferromagnetic metal powder to PDMS can improve its conductivity and make the mold a high-low surface temperature gap as low as 1.6 °C. Adding nickel powder to the PDMS mold makes the hardness 2.29 times higher than that of pure PDMS and can withstand a pressure of 7 kg cm−2, which is very conducive to hot embossing. This study used a self-designed five-sided cladding iron block base and a PDMS mold with ferromagnetic metal powder for hot embossing. This heating apparatus can quickly raise the PDMS surface temperature and emboss deep V-groove microstructures on the polycarbonate (PC) film; the replication performance can reach more than 97%.
OP11 Expanded genome-wide association study of Inflammatory Bowel Disease identifies 174 novel loci and directly implicates new genes in disease susceptibility
Authors: Fachal L ,   O.B.O. the International IBD Genetics Consortium
Published: January 2022

Background

Genome-wide association studies (GWASs) have identified 243 loci associated with inflammatory bowel disease (IBD). However, the mapping of additional disease loci and causal variants is still limited by sample size. Larger GWAS can provide further insights into causal biology.

Methods

We performed a GWAS meta-analysis of 33 cohorts, totalling 54,439 IBD patients (N=30,574 with Crohn’s disease (CD), 21,193 with Ulcerative Colitis (UC)) and 37,054 European controls. Genotype imputation was undertaken using the TOPMed diverse population panel and association tests were performed using REGENIE. These results were meta-analysed with summary statistics from 4 additional studies, a Danish cohort, the UK Biobank, deCODE, and FinnGen, totalling 73,030 IBD patients and 1 million controls, Fig1.

Results

We identified 174 novel genome-wide significant signals (32 associated with CD, 36 with UC, 106 with IBD, Fig2).

Of these, 79 are located >1Mb from any known GWAS loci. We also identified two new population specific genetic associations, Fig3.

Six new loci contain genes implicated in monogenic syndromes that include colitis: CARMIL2, DOCK8, G6PC3, HPS4, NCF1, PIK3CD. Several new loci alter the expression of nearby genes, suggesting that aberrant expression of these genes underpins the association. For instance, a new variant associated with decreased risk of IBD increases the expression of VSIR in colon Fig4.

VSIR knockout mice have increased expression of IL23 and develop chronic inflammation in multiple tissues. Fine-mapping analyses identified likely causal missense variants at three new loci. DOK2 (ORCD=1.3, 27p=2x10-12) encodes a protein expressed in macrophages and T cells. Loss of Dok2 in mice causes severe DSS-induced colitis with reduced IL17A and IL22 expression. The same variant has been recently associated with CD in a sequencing study. SHARPIN (ORCD=1.2, p=1x10-16) is part of the linear ubiquitin chain assembly complex that modulates activation of the NF-κB pathway. Loss-of-function (LOF) mutations in other proteins in the complex are associated with immunodeficiency and systemic autoinflammation. CARMIL2 (ORUC=1.2, p=1x10-10) is required for NF-κB signalling in both B and T cells. LOF mutations are associated with primary immunodeficiencies and paediatric forms of IBD.

Conclusion

The greatly expanded sample size in our latest GWAS meta-analysis has enabled the identification of low frequency variants with larger effects on IBD susceptibility than the more common variants typically identified by previous GWAS. The biological overlap between Mendelian and complex forms of IBD is demonstrated by the discovery of common non-coding variants associated with complex forms of IBD that dysregulate the function of a Mendelian IBD gene.
OP12 Segmental vs Total Colectomy for Crohn’s Disease of the colon in the biologic era. Results from the SCOTCH international, multicentric study
Authors: Pellino MD- PhD- FRCS- FEBS Coloproctology- FA G , Rottoli M , Mineccia M , Frontali A , Celentano V , Colombo F , Ardizzone S , Martí M , Espín-Basany E , Ferrero A , Panis Y , Poggioli G , Sampietro G M
Published: January 2022

Background

Previous studies suggested a role for segmental colectomy (SC) and total colectomy (TC) for colonic Crohn’s disease (cCD). TC might reduce recurrence rates, at the cost of impaired quality of life and higher stoma rates. We compared the long-term outcomes of SC and TC.

Methods

This is an international, multicentric study on data from the prospective databases of six centres. All consecutive patients operated on between 2000 and 2019 for cCD with SC or TC were included. Exclusion criteria were colorectal cancer, previous bowel resections, and lack of follow-up data. Disease extension was based on involvement of 1 to 5 colonic segments. Resection of 1–3 segments was classified as SC, resection of 4–5 segments as TC. Primary aim was surgical recurrence after SC vs TC. Secondary aims were perioperative complications, stoma formation rate, and predictors of recurrence.

Results

Data of 687 (56.2% women) patients were analysed. Mean age at diagnosis and at surgery were 30±15.8 and 40.4±15.4 years. Disease duration was 10.4 ± 8.6 years. 16.6% of patients were A1, whereas most (62.2%) were diagnosed between 17 and 40 years. Isolated cCD (L2) was present in 61.1%, ileocolic CD (L3) in 38.9%, and concomitant jejuno-ileal CD (L4) in 3.2%. Most had stricturing (B2) cCD (41.9%). Active perianal disease was found in 28.9% patients. SC was performed in 285 patients, TC in 402. The latter more frequently had isolated cCD, inflammatory (B1) disease, current (37.8 vs 16.5%, p<0.001) or previous (56 vs 32.6%, p<0.001) perianal CD, and longer disease duration (11.3 ± 8.9 vs 9.2 ± 7.9, p<0.001). Postoperative complications and mortality were similar, but TC patients more frequently required 90-day readmission (6% vs 2.1%, p=0.02). Temporary (31.6 vs 21.4%, p<0.001) and definitive (39.3vs8%, p<0.001) stomas were more likely after TC. The 15-year cumulative surgical recurrence was 36%, more likely in the TC group (44 vs 27%, Log-Rank p=0.006), and it was not affected by the number of colonic segments involved (23 vs 28%, 1–3 vs 4–5 segments p=0.2) (Fig 1). In patients with 1–3 segments involved, postoperative treatment with biologics, compared to any other regimen, reduced the risk of recurrence (25 vs 51%, p<0.001), while early age at diagnosis (p=0.02) and perianal CD (p=0.01) increased the risk. Omission of biological therapy (HR 5.4, 95%CI 5.1–5.8 p<0.001), and paediatric diagnosis (HR 2.1, 95%CI 2.3–3.1 p<0.001) were the strongest predictors of recurrence in this subgroup.

Conclusion

In this study, SC was safe, required less frequently stoma and repeated surgery, compared with TC. These findings question previous data on the topic and might be supported by the efficacy of postoperative biologic therapy on cCD.
DOP22 Clinical, biochemical and endoscopic disease activity of Inflammatory Bowel Diseases are not associated with the severity or long-term outcomes of COVID-19 – A Danish prospective population-based cohort study
Authors: Attauabi M , Dahlerup J F , Poulsen A , Hansen M R , Vester-Andersen M K , Eraslan S , Prahm A P , Pedersen N , Larsen L , Jess T , Neumann A , Haderslev K V , Molazahi A , Lødrup A B , Glerup H , Oppfeldt A M , Jensen M D , Theede K , Kiszka-Kanowitz M , Seidelin J B , Burisch J
Published: January 2022

Background

Whether the disease activity of ulcerative colitis (UC) and Crohn’s disease (CD) is correlated with the severity of coronavirus disease 2019 (COVID-19) remains poorly investigated with only few selected cohort studies having addressed this in the past.

Methods

We conducted a population-based study investigating the outcomes of COVID-19 among patients with UC and CD in Denmark. The Danish COVID-19 IBD Database is an extensive population-based database which prospectively monitors the disease course of laboratory-confirmed COVID-19 among patients with UC and CD. Severe COVID-19 was defined as COVID-19 necessitating intensive care unit admission, ventilator use, or death, while adverse COVID-19 was defined as requirement of COVID-19 related hospitalization. Clinical disease activity was measured by simple clinical colitis index and Harvey-Bradshaw Index in UC and CD, respectively. The biochemical activity was defined as C-reactive protein higher than 5 mg/L or fecal calprotectin higher than 250 μg/g. The endoscopic activity was defined as Mayo Endoscopic Subscore of at least 2 in UC, or Simple Endoscopic Score Crohn’s Disease of at least 3 for CD. Sequelae following COVID-19 were defined as symptoms that (i) developed during or after an infection consistent with COVID-19, (ii) and were present for more than 12 weeks, (iii) and were not attributable to alternative diagnoses.

Results

During the inclusion period between January 28th, 2020, to April 1st, 2021, the study included 319 patients with UC and 197 patients with CD who developed laboratory confirmed COVID-19. Of these, data on clinical, biochemical, and endoscopic activity were available among 265/319 (83.1%), 319/319 (100.0%), and 66/319 (20.7%) of patients with UC, respectively, and 140/197 (71.1%), 131/197 (66.5%), and 42/197 (21.3%) of patients with CD. Figures 1–2 outlines the outcomes of COVID-19 according to the degree of clinical, biochemical and endoscopic disease activity. In both UC and CD, clinical, biochemical, and endoscopic activity were not associated with adverse or severe COVID-19, nor long-term outcomes, in unadjusted nor adjusted analysis (Table 1).

Conclusion

In this population-based study, we found no association between disease activity of UC or CD and severity of COVID-19. These findings have implications for the risk stratification of patients with IBD acquiring COVID-19.
DOP65 Development and validation of the TUMMY-UC, a patient-reported outcome in pediatric Ulcerative Colitis: A multicenter prospective study
Authors: Turner D , Marcovitch L , Focht G , Carmon N , Tersigni C , Ledder O , Lev Tzion R , Frost K , Church P C , Baldassano R , Otley A , Kappelman M , Griffiths A
Published: January 2022

Background

In developing a patient-reported outcome (PRO) for pediatric ulcerative colitis (UC) with guidance from FDA and EMA, 8 items were previously selected based on 79 concept elicitation interviews. An observer RO (ObsRO) was determined to be required for children younger than 8 years. Here, we aimed to finalize the included items and to validate the TUMMY-UC for its psychometric properties.

Methods

The structure and exact wording of the PRO and the ObsRO versions were determined by cognitive debriefing interviews with children and their caregivers. Weights were assigned to each item based on ranking of importance. Then, in a prospective multicenter study, children with UC between 2–18 years who either underwent colonoscopy or provided stool for calprotectin completed the TUMMY-UC during 4 consecutive days, as well as 7 and 21 days thereafter for evaluating reliability and responsiveness. Construct and discriminative validity were assessed by different measures of disease severity and quality of life (QOL).

Results

In an iterative process of 129 cognitive interviews, the exact wording of the TUMMY-UC was determined. The PRO and ObsRO were formatted with identical structure to ensure conceptual equivalence for incorporating into one score. 71 children were included in the validation study (39 with colonoscopy and 32 with calprotectin; age 12.3±4.1 years, 26 (36%) in remission, 20 (29%) with moderate-severe disease). There was excellent reliability in the repeated day assessments (ICC 0.93 (0.88–0.96); p<0.001) and after 1 week in those judged as unchanged (0.90 (0.81–0.95); p<0.001). The TUMMY-UC total score had moderate to strong correlations with all constructs of disease severity: r=0.64 with UC Endoscopic Index of Severity (UCEIS, Figure 1), r=0.66 with IMPACT QOL questionnaire, r=0.43 with calprotectin, r=0.82 with the PUCAI, r=0.76 with patient/caregiver global assessment, r=0.5 with CRP, and r=-0.36 with albumin (all p<0.015). There was a slight superiority to combining TUMMY-UC scores of two consecutive days. The index had excellent discrimination of disease activity categories (figure 2) with a score<9 defining remission (Sen=93%, Spec=84%, AUROC=0.95 (95%CI 0.89–0.99). Showing high responsiveness, the DTUMMY-UC differentiated well between children who improved, worsened or remained unchanged after 3 weeks (Figure 3). The best cutoff of the TUMMY-UC to define response was a change of ≥10 points (AUROC 0.93 (95%CI 0.86–0.99)).

Conclusion

The TUMMY-UC, constructed from a PRO and ObsRO versions for children 8–18 and 2–7 years, respectively, is a reliable, valid and responsive index which can be now used in clinical practice and as an outcome measure in clinical trials.
P029 Expression of miR-21 in mucosal biopsies give clues to anti-TNF treatment non-response in IBD children and adults
Authors: Pallikkunnath James J , Schnack Nielsen B , Langholz E , Mikkel M , Estrid H , Buhl Riis L
Published: January 2022

Background

The use of anti-tumor necrosis factor (TNF) treatment has improved the treatment of IBD patients. However, approximately 30% of patients fail to respond to TNF inhibitors, and up to 50% of the patients who initially benefited from treatment with TNF inhibitors lose the response over time. Thus, identifying predictors of non-response and deciding on a treatment strategy according to biomarker profiles could enhance overall IBD disease management. MicroRNA-21 (miR-21) has been found to confer drug resistance to e.g. trastuzumab, 5-fluorouracil, and cisplatin. In this study, we hypothesized that miR-21 may play a role in anti-TNF drug resistance and therefore, miR-21 levels may be a predictive biomarker of anti TNF response in IBD.

Methods

Archived formalin-fixed, paraffin-embedded (FFPE) mucosal biopsies of IBD patients (30 adults and 27 children) were used in this study. All biopsies were collected at the time of initiation of biologics. Patients were stratified into three groups according to treatment response: Responders, Primary non-responders (PNR), and Secondary non-responders (SNR). Responders were treated with anti-TNF for a minimum of 3 years and did not experience loss of response thereafter. PNRs lost response during the first year of treatment. SNRs were treated for a minimum of 3 years with subsequent loss of response. MiR-21 expressions were quantified using Quantitative Real-Time PCR (miRCURY LNA RT Kit, Qiagen). Expression of miR-27a was used as the endogenous reference microRNA based on previous studies.

Results

In adults, responders had less miR-21 expression compared to PNRs and SNRs (relative median of miR-21 expression in folds [IQR]: 3.45[3.36 - 4.2], 5.05 [3.61 - 6.88], and 7.58 [6.21 - 8.2] in responders, PNRs, and SNRs respectively, p=0.04 and p=<0.01). In children, however, responders had an increased miR-21 expression compared to PNRs and SNRs (relative median of miR-21 expression in folds [IQR]: 19.94[15.88–24.59], 9.79[7.69– 14.44], and 10.58[5.66–12.91] in responders, PNRs, and SNRs respectively, p=0.03 and p=0.01). Expression of MiR-21 was found to be higher in children than adults (relative median of miR-21 expression in folds [IQR]: 4.65[3.45–7.21], and 13.6[8.37–19.05], respectively, p=<0.01).

Conclusion

Higher miR-21 expression indicates a higher response rate in children, whereas higher miR-21 expression could predict resistance to anti-TNF treatment in adults. MiR-21 expression could potentially be used as a predictive biomarker for anti-TNF treatment response in IBD patients with varying measures for children and adults.
P034 DISRUPTive liquid biopsies in Inflammatory Bowel Disease (DISRUPT-IBD): Release of exosomal and molecular tissue signals by transabdominal ultrasound?
Authors: Tran F , Scharmacher A , Mishra N , Barann N , Sievers L K , Juzenas S , Bernardes J P , Lessing M , Lassen A , Rosenstiel P , Schreiber S
Published: January 2022

Background

A major drawback in diagnosis and monitoring of IBD are insufficient biomarkers that do not correlate well with tissue disease activity. Inflammation and cellular stress lead to an increased release of exosomes (Lipinski et al, 2019, EMBO J) carrying inflammatory signal proteins as cargo (Wozniak et al, 2020, J Cell Biol). Interestingly, colorectal cancer cells strongly release tumor markers after stimulation by sonography waves, probably through the disruptive energy of standard ultrasound (D’Souza et al, 2009, PNAS). We thus hypothesize that application of ultrasound waves on inflamed intestinal tissue in active IBD induces the release of tissue-specific exosomes that can be detected in the peripheral blood and used as novel biomarkers.

Methods

26 patients with different degrees of disease activity and various ongoing therapies with IBD were included in a pilot trial. Serum was taken before and 30 minutes after diagnostic transabdominal ultrasound. Serum exosomes were precipitated (using ExoQuick) and exosomal (exo-)miRNA were isolated for miRNA sequencing using SeraMir protocol. Exosomal proteins were isolated for quantification of inflammatory markers (as exosomal cargo).

Results

We found a correlation between exo-miRNA concentration and disease severity, determined by clinical assessment scores and sonographic findings. Exo-miRNA sequencing revealed a select few miRNAs to be induced by sonography. However, the overall composition of annotated miRNA transcripts did not separate samples according to sampling timepoints. Among these “inducible” exo-miRNA, we found hsa-miR-942, which is involved in cell cycle and Wnt signaling in intestinal epithelial cells, to be significantly induced in higher grade intestinal inflammation. The exosomal protein concentrations did not correlate with disease severity at baseline, but were increased after sonography in severe intestinal inflammation. We did not find markers of the inflammasome apparatus as inducible exosomal cargos.

Conclusion

Sonography-induced exosomal markers, e.g., exo-miRNAs, could become novel biomarkers for intestinal inflammation in IBD. Further exploration of the functional role of inducible biomarkers and continued investigation of exosomal miRNA and protein profiling will be performed.
P050 A comparison of the Gut Microbiota in Pregnant Women with and without Inflammatory Bowel Disease and Their Offspring in Hong Kong and United States
Authors: Hu J , Agrawal M , Tarassishin L , Rendon A , Picker M , Kalash O , Eisele C , Ching J Y , Wong A , Zhan H , Ng S C , Colombel J F , Peter I
Published: January 2022

Background

Data on the impact of geographic location on the gut microbiota of pregnant women with and without inflammatory bowel disease (IBD) and their infants are lacking.

Methods

420 pregnant women with or without IBD and 331 infants were prospectively enrolled in the MECONIUM (Exploring MEChanisms Of disease traNsmission In Utero through the Microbiome) study in Hong Kong (HK) and United States (US). Of these individuals, the fecal microbiota compositions from 105 mothers (47 from HK and 58 from US) at third trimester and 54 babies (26 from HK and 28 from US) at 1 month were surveyed using 16s rRNA sequencing.

Results

The birthweight of infants in HK was significantly lower compared to that of infants in the US (p-value<0.001), while other baseline characteristics were comparable (Table 1). We observed differential gut microbiome beta-diversity between pregnant women without IBD (PERMANOVA test, p-value<0.05) and their infants (p<0.05) from HK and the US (Figure 1A). At the genus level, compared to pregnant women without IBD in the US, those in HK had a higher abundance of 15 taxa including Bifidobacterium, Faecalibacterium and Bacteroides and lower abundance of 6 taxa including Blautia and Turicibacter (Figure 1B). Compared to infants born to women without IBD in the US, those in HK had higher abundance of 3 taxa including Klebstella and Escherichia/Shigella and lower abundance of Enterococcus (Figure 1B). When comparing the gut microbiome alpha-diversity of women with and without IBD (Figure 1C), and that of their infants, both were lower in HK, (p-values= 0.077, 0.13, respectively) and in the US (p-values=0.0024, 0.019, respectively).

Conclusion

Our results suggest the impact of geographic location on the gut microbiome diversity and composition irrespective of IBD status. Maternal IBD is associated with reduced microbiome diversity in infants in both the US and HK.
P058 IL-36 signaling in Crohn’s disease – characterization of a patient with an IL36RA mutation
Authors: Hecker J , Letizia M , Loescher B S , Franke A , Weidinger C , Siegmund B
Published: January 2022

Background

The interleukin 36 (IL-36) family consists of three agonists (IL-36α, IL-36β, IL-36γ), which activate the NF-κB pathway and lead to the production of pro-inflammatory cytokines and the natural antagonist (IL-36RA), which inhibits IL-36 signaling.

While it is known that IL-36 signaling is important in the skin, it has been only recently reported that IL-36 might play an important role in maintaining gut homeostasis and in the development of fibrosis (Scheibe et al., 2019). However, it is not clear how IL-36 signaling contributes to the development of intestinal inflammation and which cell types are involved in this process.

To shed more light on the role of IL-36 in intestinal inflammation, we took the opportunity to perform an in-depth characterization of a Crohn’s disease patient with a mutation in IL36RA and identify cell subsets responding to IL-36 stimulation.

Methods

By whole exome-sequencing of EDTA blood we identified in a Crohn’s disease patient a heterozygous mutation in IL36RA (p.Ser113Leu), which we confirmed by Sanger sequencing. By ELISA, we quantified IL-36RA serum levels in comparison to other Crohn’s disease (CD) patients and healthy donors (HD). Finally, we stimulated peripheral blood mononuclear cells (PBMCs) of the IL-36RA patient, CD patients, and HDs with ionomycin/PMA, LPS or IL-36α and performed deep immune profiling by mass cytometry with 35 markers.

Results

Our IL36RA mutation carrying patient presented with a severe course of Crohn’s disease and consecutive of fibrosis, which was resistant to all commonly used treatment options. As an individual treatment, autologous stem cell transplantation was performed, but did not lead to long-term improvement in symptoms.

By ELISA, we found strongly elevated IL-36RA levels in the serum of our patient compared to CDs and HDs. Mass cytometry analysis revealed that the IL36RA mutation does not lead to major shifts in the immune cell composition of the blood, as the frequencies of B, T, NK, and myeloid cells in PBMCs of our patient were comparable to those in HDs and CDs. Furthermore, our data revealed that IL-36α stimulation mainly induced TNFα and IL-6 expression in myeloid cells as well as IFNγ expression in NK cells but did not affect T and B cells.

Conclusion

Our data is the first description of a Crohn’s disease patient with an IL36RA mutation and indicate that defects in IL-36 signaling should be considered as a possible cause for therapy-refractory and fibrotic Crohn’s disease. Furthermore, we identified NK cells and myeloid cells as main responders to IL-36α stimulation. As next step, we plan to use recombinant produced, mutant IL-36RA in in-vitro assays with immune cells and fibroblasts to study the effect of the mutation on the IL-36RA function in more depth.
P063 Expression of the coinhibitory receptor TIGIT on memory CD4+ T cells is induced by TCR ligation and retinoic acid co-stimulation and is elicited during microbial colonization of the intestine
Authors: Barendregt D , Joosse M E , van Berkel L A , van Schoonhoven A , Samsom J N
Published: January 2022

Background

The coinhibitory receptor T cell immunoglobulin and ITIM domain (TIGIT) is widely expressed by immune cells, including CD4+ T cells. Previously, we showed that circulating gut homing CD38+ (CD62LnegCD4+) effector T cells are enriched for TIGIT+ cells with an immunoregulatory phenotype. In newly diagnosed inflammatory bowel disease (IBD) patients, low frequencies of regulatory TIGIT+ cells in circulating gut homing CD38+CD62LnegCD4+ effector T cells associate with more severe disease. IBD is a chronic disease characterized by aberrant CD4+ T cell responses to intestinal microbiota. Together, this led us to hypothesize that TIGIT+CD4+ T cells regulate immune responses to intestinal bacteria thereby maintaining intestinal homeostasis.

Methods

We studied TIGIT expression in subpopulations of murine and human intestinal CD4+ T cells. In addition, we assessed the signals required for the induction of TIGIT expression in vitro using CD4+ T cells isolated from human healthy donor peripheral blood.

Results

TIGIT was expressed by more than 50% of memory, but not naïve, CD4+ T cells in the intestinal lamina propria of both mouse and human. Both Foxp3+ and Foxp3neg intestinal CD4+ T cells expressed TIGIT. Intestinal TIGIT expression depended on the presence of microbial antigens, as conventionalization of germ-free mice with specific-pathogen free (SPF) microbiota dramatically increased TIGIT expression in both small intestine and colon. T cell receptor (TCR) ligation mimicked by anti-CD3 stimulation was essential to induce TIGIT expression on CD4+ T cells isolated from human peripheral blood, but CD28 co-stimulation led to reduced TIGIT expression. TIGIT expression could only be induced on antigen-experienced CD4+ memory T cells, but not naïve CD4+ T cells. Using the calcium ionophore ionomycin and the calcineurin inhibitor tacrolimus, we demonstrated that the induction of TIGIT expression upon TCR ligation depended on downstream calcium-dependent signaling. We next assessed whether retinoic acid (RA), a metabolite produced by intestinal antigen-presenting cells (APCs), can further enhance TIGIT expression. RA plays an important role in mucosal immune responses, as it promotes the development of Foxp3+ regulatory T cells and induces the expression of the gut-homing markers CD38 and α4β7. We showed that co-stimulation with RA also significantly enhanced TCR-induced TIGIT expression, as it increased both the mean fluorescence intensity (MFI) and frequencies of TIGIT+ cells in CD4+ memory T cells.

Conclusion

In conclusion, these data argue that TCR ligation and retinoic acid production by intestinal APCs induces TIGIT expression on CD4+ memory T cells, which in turn may contribute to regulation of immune responses against microbial antigens.
P088 Metabolomic analysis reveals differences among UC and non-IBD human colonic resections: role of GPCRs
Authors: Bauset C , Carda-Diéguez M , Buetas E , Coll S , Lis-López L , Seco-Cervera M , Navarro F , Mira Á , Calatayud S , Barrachina M D , Cosín-Roger J
Published: January 2022

Background

Metabolomics is a recent technique that has bounced into Inflammatory Bowel Diseases (IBD) due to its capacity to elucidate specific metabolites involved in the pathology and changes in the metabolomic profile have been detected in urine, blood or feces from UC patients. G-protein coupled receptors (GPCRs) have been recently identified as promising pharmacological targets. We aim to characterize the metabolomic profile and metabolite-sensing GPCRs expression in colonic resections from UC patients.

Methods

Colonic resections from UC (n=18) and non-IBD (n=20) patients were obtained. Metabolomic analysis was performed using Nuclear Magnetic Resonance (NMR) to study polar metabolites and Gas-Chromatography or Liquid-Chromatography Mass-Spectrometry to study non-polar metabolites. Results are expressed as μg of metabolite per gram of tissue. Gene expression of GPCRs was analyzed by qPCR. Data were expressed as fold induction vs control (mean±SEM) and compared by a t-test. A p-value<0.05 was considered statistically significant. Pearson correlation matrix were performed with R or mixOmics library in R.

Results

Metabolomic analysis revealed in colon of UC patients significant increased levels of propionic acid (7.7±1.1), undecanoic acid (0.3±0.02) decanoic acid (4.5±0.9), myristic acid (64.5±8.7), α-linoleic acid (23.1±4.0), aspartic acid (33.9±3.4), phenylalanine (8.8±1.6), glutamic acid, (136.3±10.8), b-hydroxybutyric (8.3±0.9) acid and lactic acid (297.5±34.7) vs non-IBD patients. Gene expression of GPR43 (22.7±9.5), GPR41 (4.7±1.7), GPR109a (19.1±5.3), GPR109b (13.6±4.6), GPR91 (13.2±5.7), GPR84 (6.7±2.0), GPR40 (6.6±1.8), GPR65 (3.0±0.5) and GPR68 (4.6±1.0) were significantly increased in UC patients compared with controls. In contrast, GPR120 (0.9±0.3), GPR119 (0.6±0.2) and GPR35 (0.5±0.1) were significantly reduced in UC patients. N-oleylethanolamide positively correlates with most of GPCRs, especially GPR68, GPR84 and GPR91 while acetic and succinic acids negatively correlate with GPR4 (Fig.1A). In UC patients, medium-chain fatty acids (FA) and most long-chain FA positively correlate with GPR84, GPR142, GPR43, GPR109a, GPR109b, GPR91 and GPR132 (Fig. 1C).

Fig1. Graphs show the correlations between data relative to mRNA expression of GPCRs (expressed as ΔCt) vs metabolites. (A) Data from controls and UC. (B) Only controls. (C) Only UC.

Conclusion

Increased levels of several metabolites and GPCRs are detected in the colon of UC patients and their correlations suggest potential candidates to be involved in UC pathophysiology.
P106 Macrophages as a source of NOTCH Ligands in Crohn’s disease: implications in fibrosis
Authors: Edo M M , Macias-Ceja D C , Bauset C , Lis L , Coll S , Seco-Cervera M , Cosin-Roger J , Calatayud S , Barrachina M D , Ortiz-Masiá D
Published: January 2022

Background

Fibrosis constitute the main complications associated to Crohn′s disease (CD). NOTCH signalling has been implicated in lung, kidney, liver and cardiac fibrosis. Macrophages contribute to fibrosis through the release of different mediators and the pattern of secretion may vary according to their microenvironment. The aim of the present study is to analyze the role of NOTCH ligands derived from macrophages in the complications of CD.

Methods

The aim of the present study is to analyze the role of NOTCH ligands derived from macrophages in the complications of CD. We have analyzed: the protein expression of NOTCH ligands and receptors in CD patients with fistulizing (B3) and stenting pattern (B2), the protein expression of NOTCH ligands in macrophages treated with the main cytokines present in CD patients (IFNγ-, IL10-, IL4, TNFα-U937 treated cells), the protein expression of HES1 and fibrosis markers in DLL4-HT29 and DLL3-HT29 treated cells. Results are expressed as fold induction (mean±SEM). Statistical analysis was performed with one-way ANOVA followed by Newman-Keuls test or t-tet.

Results

The expression of DLL4 and NOTCH4 were significantly higher in intestinal samples from B3 CD patients (3,2 ± 0,6 N=4* and 3,8 ± 0,6 N=8*, respectively) than in B2 patients (1,6 ± 0,2 N=4 and 1,7 ± 0,3 N=8, respectively) and controls (1,0 ± 0,1N=3 and 1,0 ± 0,1 N=8, respectively). IFNγ-U937 treated cells increased significantly the protein expression of DLL3 and DLL4 (1,6 ± 0,09 N=6* and 1,3 ± 0,1 N=7*, respectively) respect vehicle; IL4 increased significantly the expression of DLL4 (1,4 ± 0,1 N=7*) and TNFα increased significantly the expression of DLL3 (1,4 ± 0,1 N=5*), respect vehicle. DLL4-HT29 treated cells increased significantly fibrosis markers (VIMENTIN: 1,7 ± 0,1 N=3*; SNAIL: 2,2 ± 0,2 N=3*) and HES1 (1,4 ± 0,06 N=3*), respect vehicle (1,0 ± 0,07 N=6; 1,0 ± 0,05 N=6; and 1,0 ± 0,05 N=6, respectively). DLL3-HT29 treated cells only produced a reduction in the protein expression of ECADHERIN (0,4 ± 0,1 N=3*), respect vehicle (1,0 ± 0,09 N=6).

Conclusion

Macrophages may act as a source of NOTCH ligands who could act as fibrosis mediators in CD patients with a fistulizing (B3) behavior. The microenvironment rich in IFNγ could activate the fibrosis process in epithelial cells by favoring the expression of DLL4 and DLL3 in macrophages. DLL4 mainly activates transcription factors involved in mesenchymal epithelial transition in colonic epithelial cells (SNAIL), while DLL3 seems to have a more relevant role in cell-cell junction modification (ECADHERIN).