Long noncoding RNA-SNHG20 promotes silica-induced pulmonary fibrosis by miR-490-3p/TGFBR1 axis

Silicosis is a universal occupational disease, which is caused by long-term crystalline silica exposure. Recent studies have shown that noncoding RNAs participate in diverse pathological cellular pathways. However, the precise regulation mechanism remains limited in silicosis. Here, we established a silica-induced mouse fibrosis model (all mice received a one-time intratracheal instillation with 50 mg/kg of silica in 0.05 mL sterile saline). MiR-490-3p was significantly downregulated in silica-induced fibrotic mouse lung tissues and TGF-β1 treated fibroblasts. Moreover, overexpressed miR-490-3p could relieve silica-induced lung fibrosis in vivo, and prevent the process of fibroblast-to-myofibroblast transition(FMT)in vitro. Mechanistically, TGFBR1 was one of the major target genes of miR-490-3p, and tightly associated with the process of fibroblasts activation. SNHG20, as opposed to miR-490-3p expression, was elevated in TGF-β1-treated fibroblast cell lines and contributed to decreased levels of miR-490-3p. Taken together, these data indicated that miR-490-3p plays a key role in silica-induced pulmonary fibrosis. Our results suggested that SNHG20/miR-490-3p/TGFBR1 axis may provide a new treatment target of pulmonary fibrosis.

Light quantum control of persisting Higgs modes in iron-based superconductors

The Higgs mechanism, i.e., spontaneous symmetry breaking of the quantum vacuum, is a cross-disciplinary principle, universal for understanding dark energy, antimatter and quantum materials, from superconductivity to magnetism. Unlike one-band superconductors (SCs), a conceptually distinct Higgs amplitude mode can arise in multi-band, unconventional superconductors  via strong interband Coulomb interaction, but is yet to be accessed. Here we discover such hybrid Higgs mode and demonstrate its quantum control by light in iron-based high-temperature SCs. Using terahertz (THz) two-pulse coherent spectroscopy, we observe a tunable amplitude mode coherent oscillation of the complex order parameter from coupled lower and upper bands. The nonlinear dependence of the hybrid Higgs mode on the THz driving fields is distinct from any known SC results: we observe a large reversible modulation of resonance strength, yet with a persisting mode frequency. Together with quantum kinetic modeling of a hybrid Higgs mechanism, distinct from charge-density fluctuations and without invoking phonons or disorder, our result provides compelling evidence for a light-controlled coupling between the electron and hole amplitude modes assisted by strong interband quantum entanglement. Such light-control of Higgs hybridization can be extended to probe many-body entanglement and hidden symmetries in other complex systems.

A collective excitation called Higgs mode may arise in multi-band superconductors via strong interband interaction, but it is yet to be accessed. Here, the authors observe a tunable coherent amplitude oscillation of the order parameter in Ba(Fe_1−xCo_x)₂As₂, suggesting appearance and control of the Higgs mode by light tuning interband interaction.

A review of a potential and promising probiotic candidate-Akkermansia muciniphila

Akkermansia muciniphila, a common colonizer in the intestinal mucus layer of humans, has gradually been considered as promising candidate for the next-generation probiotic, given its physiological benefits from animal and human studies. This article comprehensively reviewed A. muciniphila from the published peer-reviewed articles in the aspects of its role in the host physiology and commonly consumed food that can boost its abundance, which should provide useful and fundamental information for scientists and engineers and even ordinary consumers. Akkermansia muciniphila is not only a crucial biomarker that indicates the physiology of human beings but also has huge potential to become a probiotic given its physiological benefits in various clinical scenarios. Current barriers in terms of regulations, necessity for large-scale clinical experiments and production feasibility need to be resolved before A. muciniphila can be widely applied as the next-generation probiotic.

[Effects of two dimensional gray-scale blood flow imaging combined with color Doppler flow imaging in guiding arterial puncture and catheterization through wounds in patients with large burns]

Objective: To explore the effects of two dimensional gray-scale blood flow imaging (hereinafter referred to as " B-flow" ) combined with color Doppler flow imaging (CDFI) in guiding arterial puncture and catheterization through wounds in patients with large burns. Methods: Sixty-seven patients with large burns who met the inclusion criteria and hospitalized in the First Hospital of Jilin University from January 2017 to January 2019 were enrolled in the prospectively randomized control study. According to the random number table, CDFI alone group was allocated with 35 patients (23 males and 12 females) and B-flow+ CDFI group with 32 patients (22 males and 10 females), aged 19-60 and 18-58 years, respectively. According to the progress of the disease, arterial puncture and catheterization were performed in the right time. During the operation, CDFI was used alone for guidance in patients of CDFI alone group, while B-flow and CDFI were used together for guidance in patients of B-flow+ CDIF group. Based on the first time of catheterization, the catheterization location, one-time catheterization success rate, post-back stitching re-catheterization success rate, catheterization failure rate, catheterization duration, and incidences of wound sepsis, catheter-related bloodstream infection, and arterial thrombosis within post catheterization day (PCD) 3 of patients in the two groups were recorded. Data were statistically analyzed with the independent-sample t test, chi-square test or Fisher's exact probability test. Results: (1) All the patients underwent catheterization through wounds, and there was no statistically significant difference in catheterization location of patients between the two groups (χ(2)=0.574, P>0.05). The one-time catheterization success rate of patients in B-flow+ CDFI group was 81.25% (26/32), which was obviously higher than 51.43% (18/35) in CDFI alone group (χ(2)=6.594, P<0.05). The catheterization failure rate of patients in B-flow+ CDFI group was 3.12% (1/32), which was obviously lower than 20.00% (7/35) in CDFI alone group (P<0.05). The post-back stitching re-catheterization success rate of patients was similar between the two groups (χ(2)=1.029, P>0.05). (3) The catheterization duration of patients was (15.7±1.1) min in B-flow+ CDFI group, which was obviously shorter than (17.1±2.2) min in CDFI alone group (t=11.316, P<0.01). (4) Within PCD 3, the incidences of wound sepsis and catheter-related bloodstream infection of patients in CDFI alone group were 2.86% (1/35) and 0, close to 0 and 3.12% (1/32) in B-flow+ CDFI group (P>0.05); the incidence of arterial thrombosis of patients in B-flow+ CDFI group was 0, which was obviously lower than 20.00% (7/35) in CDFI alone group (P<0.05). Conclusions: Compared with CDFI alone, B-flow combined with CDFI can improve the success rate of arterial puncture and catheterization through wounds in large area burn patients, shorten the catheterization duration, and effectively reduce the incidence of arterial thrombosis after catheterization, with a good clinical application value.

Terahertz Second-Harmonic Generation from Lightwave Acceleration of Symmetry-Breaking Nonlinear Supercurrents

We report terahertz (THz) light-induced second harmonic generation, in superconductors with inversion symmetry that forbid even-order nonlinearities. The THz second harmonic emission vanishes above the superconductor critical temperature and arises from precession of twisted Anderson pseudospins at a multicycle, THz driving frequency that is not allowed by equilibrium symmetry. We explain the microscopic physics by a dynamical symmetry breaking principle at sub-THz-cycle by using quantum kinetic modeling of the interplay between strong THz-lightwave nonlinearity and pulse propagation. The resulting nonzero integrated pulse area inside the superconductor leads to light-induced nonlinear supercurrents due to subcycle Cooper pair acceleration, in contrast to dc-biased superconductors, which can be controlled by the band structure and THz driving field below the superconducting gap.

Ultrafast Control of Excitonic Rashba Fine Structure by Phonon Coherence in the Metal Halide Perovskite CH_{3}NH_{3}PbI_{3}

We discover hidden Rashba fine structure in CH_{3}NH_{3}PbI_{3} and demonstrate its quantum control by vibrational coherence through symmetry-selective vibronic (electron-phonon) coupling. Above a critical threshold of a single-cycle terahertz pump field, a Raman phonon mode distinctly modulates the middle excitonic states with persistent coherence for more than ten times longer than the ones on two sides that predominately couple to infrared phonons. These vibronic quantum beats, together with first-principles modeling of phonon periodically modulated Rashba parameters, identify a threefold excitonic fine structure splitting, i.e., optically forbidden, degenerate dark states in between two bright ones with a narrow, ∼3  nm splitting. Harnessing of vibronic quantum coherence and symmetry inspires light-perovskite quantum control and sub-THz-cycle "Rashba engineering" of spin-split bands for ultimate multifunction device.

[Advances in the research of pain assessment and non-drug intervention in burn children]

Children are a high-risk group of burn, and burn pain is a special type of pain. Because children of different ages have different cognitive ability and behavioral response to pain, thus it is particularly difficult to effectively evaluate the pain. It is very important for medical staff to understand the pain of children, to define the adverse reactions of pain, to evaluate and take appropriate pain intervention measures in time and effectively. In this paper, different evaluation methods of burn pain in children and non-drug intervention related measures were reviewed in order to provide references for clinical practice.

A three-microRNA signature predicts clinical outcome in breast cancer patients

OBJECTIVE

Breast invasive carcinoma (BRCA) is a complex polygenic disease characterized by molecular and histological heterogeneity. An effort is underway to explore and investigate multiple reliable prognostic markers to improve management of BRCA patients and provide novel therapeutic targets. The aim of the study is to identify the prognostic miRNA signature in BRCA patients.

PATIENTS AND METHODS

The miRNA-sequencing data and clinical information of BRCA patients were downloaded from The Cancer Genome Atlas (TCGA) database.

RESULTS

A total of 106 differentially expressed miRNAs were identified between BRCA tissues and matched normal tissues, including 81 up-regulated miRNAs and 25 down-regulated miRNAs. Then, we established a set of three-miRNA signature that was significantly associated with BRCA patients' survival. Using the prognostic three-miRNA signature, we classified the BRCA patients into high-risk and low-risk groups. Multivariate Cox regression demonstrated that the prognostic power of the three-miRNA signature was independent of other clinical variables. Functional enrichment analysis suggested that three prognostic miRNAs may be involved in known BRCA-related KEGG pathways and biological processes.

CONCLUSIONS

We demonstrated that three-miRNA signature could be a potential biomarker for predicting clinical outcomes for BRCA patients.

[Correlation of capillary plexus with visual acuity in idiopathic macular epiretinal membrane eyes using optical coherence tomography angiography]

Objective: To observe changes in foveal avascular zone(FAZ) and capillary plexus in idiopathic macular epiretinal membrane (IMEM) in optical coherence tomography angiography (OCTA) and analyze their correlation with the visual acuity. Methods: Cross-sectional study. 42 patients (15 Males and 27 females, age 64.8) from the Eye Hospital of Wenzhou Medical University were included with 51 eyes diagnosed as IMEM (IMEM group), and 23 normal eyes (9 Males and 14 females, control group). All patients received the examination of fissure lamp combined with fundus pre-set lens, best corrected visual acuity (BCVA), OCT angiography (OCTA) and fundus photo. OCTA was performed on 3 mm× 3 mm sections centred on the fovea. The software automatically measured the superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density(VD) and retinal thickness(RT) and FAZ area. The IMEM eyes were compared with the normal eyes and correlation between the parameters of OCTA and BCVA was analyzed in IMEM. Independent-sample t test and MannWhitney test were used for comparison between groups, and Spearman test was used for correlation analysis. Results: LogMAR BCVA in the IMEM group was 0.40(0.15, 0.70), in the control group was 0.10(0.05, 0.22). FAZ area of IMEM group was (0.09±0.05) mm(2), while that of control group was (0.34±0.13)mm(2).Compared with the control group, in IMEM group, the BCVA was worse (Z=-4.443, P<0.001), FAZ area was smaller (t=-9.198, P<0.001), RT was increased (P<0.001), The foveal DCP and SCP vessel density was increased (t=4.280, 9.079, P<0.01), The parafoveal DCP vessel density was decreased (P<0.05), The parafoveal SCP vessel density was decreased in superior, inferior and nasal side (t=-2.759, Z=-3.998, Z=-2.108; P<0.05). The BCVA was negatively correlated with FAZ area (r=-0.337, P=0.017), positively correlated with center macular thickness (r=0.324, P=0.020). The BCVA was no correlated with foveal VD and parafoveal DCP vessel density (P>0.05), but correlated with SCP vessel density(P<0.05). Conclusions: In the IMEM eyes the BCVA was worse, FAZ area was smaller, foveal vessel density was increased and the parafoveal vessel density was decreased compared with the normal eyes. The smaller the FAZ area, the smaller foveal SCP vessel density, the poorer BCVA. There was no correlation between BCVA and DCP vessel density. Changes in VD in IMEM eyes may lead to changes in vision. (Chin J Ophthalmol, 2019, 55:757-762).

Whole-genome SNP data unravel population structure and signatures of selection for black plumage of indigenous chicken breeds from Jiangxi province, China

Ten indigenous chicken breeds were originally distributed in Jiangxi Province, China, and they define a critical component of Chinese chicken genetic resources. We have investigated the population genetics of seven Jiangxi chicken breeds using 600K chicken BeadChip SNP data. To provide a genome-wide perspective for the population structure of all 10 Jiangxi chicken breeds, we herein genotyped 78 additional individuals from the seven breeds and 63 chickens from three uninvestigated breeds-Yugan Black (YG), Nancheng Black (NC) and Wanzai Yellow using 55K chicken SNP arrays. We then explored merged data of 17 101 SNPs from 235 individuals to infer the population structure of the 10 breeds. We showed that NC and YG are two regional populations of the same breed, as individuals from the two populations clustered together to form a branch separate from the other breeds in the neighbor-joining tree, they always grouped together in multidimensional principal component analyses and they displayed an identical pattern of ancestral lineage composition. Hence, NC and YG should be considered a single breed in the state-supported conservation scheme. Moreover, we conducted a genome scan for signatures of selection for black plumage. bayescan and hapflk analyses of two contrasting groups (three black-feathered breeds vs. six non-black-feathered breeds) consistently detected 25 putative regions under selection. Nine pigmentation- associated genes (DCT, SLC24A5, SLC30A4, MYO5A, CYP19A1, NADK2, SLC45A2, GNAQ and DCP2) reside within these regions, and these genes are interesting candidates for black plumage and provide a starting point for further identification of causative mutations for black feathers in chicken.

HPV Status Improves Classification of Head and Neck Gray Zone Cancers

In epidemiologic studies, patients with head and neck squamous cell carcinoma (HNSCC) are classified mainly by the International Classification of Diseases (ICD) codes. However, some patients are of an unclear subsite, the “gray zone” cases, which could reflect ICD coding error, absence of primary subsite, or extensive primary tumors that cross over multiple subsites of the oral cavity and oropharynx. Patients with gray zone squamous cell carcinomas were compared with patients with oral cavity squamous cell carcinoma (OSCC) or oropharyngeal squamous cell carcinoma (OPSCC) and stratified by human papillomavirus (HPV) status that was determined by p16 immunostaining or HPV serology. Comparisons consisted of clinicodemographic features and prognostic outcomes presented by Kaplan-Meier curves and Cox proportional hazards regression models, reported as hazard ratios. There were 158 consecutive patients with gray zone HNSCC diagnosed at the Princess Margaret Cancer Center between 2006 and 2017: 66 had subsite coding discrepancies against the clinician’s documentation (“discrepant” cases; e.g., the diagnosis by the clinician was OSCC, while the classification by ICD coding was OPSCC), while 92 were squamous cell carcinoma of unknown primary of the head and neck (SCCUPHN) after complete diagnostic workup. Comparators included 721 consecutive OSCC and 938 OPSCC adult cases. All HPV-positive cohorts (OPSCC, discrepant, and SCCUPHN) had similar clinicodemographic characteristics and better 3- and 5-y overall survival and disease-free survival than their HPV-negative counterparts. In contrast, HPV-negative discrepant cases had prognostic outcomes most similar to HPV-negative OPSCC cases, while HPV-negative SCCUPHN had survival outcomes most similar to those of patients with OSCC in this study. HPV-positive status can improve the classification of patients with unclear or discrepant oral/oropharyngeal subsite, an improvement over classification systems that are solely clinician defined or conducted through ICD coding. However, due to clinical practice, we could not make definitive reclassification for patients with HPV-negative gray zone HNSCC.

[Human leukocyte antigen polymorphism of HIV infected persons without disease progress for long-term in Henan province, 2011-2016]

Objective: To understand the disease progression and human leukocyte antigen (HLA) gene polymorphism of HIV-infected persons without disease progress for long term, also known as long-term non-progressors (LTNPs), in Henan province. Methods: A retrospective study was conducted in 48 LTNPs with complete detection and follow-up information during 2011-2016 in Henan. Changes of CD(4)(+)T cells counts (CD(4)) and viral load (VL) during follow-up period were discussed. Polymerase chain reaction-sequence-specific oligonucleotide probe (PCR-SSOP) was used for the analyses of HLA-A, HLA-B and HLA-DRB1 alleles between LTNPs and healthy controls. Results: From 2011 to 2016, forty-eight LTNPs showed a decrease of the quartile (P(25)-P(75)) of CD(4) from 601.00 (488.50-708.72)/μl to 494.00 (367.00-672.00)/μl, and the difference was significant (P<0.05). The increase of the quartile (P(25)-P(75)) of log(10)VL from 3.40 (2.87-3.97) to 3.48 (2.60-4.37), but the difference was not significant (P>0.05). HLA polymorphism analysis revealed that HLA-B*13:02 and HLA-B*40:06 were more common in LTNPs (P<0.05), while HLA-B*46:01 and HLA-DRB1*09:01 were more common in healthy controls (P<0.05). Conclusions: The CD(4) of LTNPs in Henan showed a downward trend year by year. HLA-B*13:02 and B*40:06 might be associated with delayed disease progression for HIV infected persons in Henan.

Abstract P4-06-05: PanCancer profiling reveals population difference in breast cancer immune microenvironment

BACKGROUND. Breast Cancer (BC) outcome in patients (pts) of African ancestry (AA) is worse than pts of European ancestry (EA) despite accounting for socioeconomic status and access. AA have higher hormone receptor negative (HR-) and Triple Negative (TNBC) tumors, subtypes associated with stronger presence of tumor infiltrating lymphocytes (TILs). We hypothesize that BC Immune Microenvironment (IME) composition differs by ancestry, and describe IME from two independent datasets.

METHODS. Transcriptome data from the Cancer Genome Atlas (TCGA) (Group 1, Gp1) were used to estimate 22 IME cell types in BC samples by CIBERSORT. Clinical and overall survival (OS) data were accessed from XENA. Gp2 tissue samples were obtained from Women's Circle of Health study and Pathology Resource Network at Roswell Park Comprehensive Cancer Center and processed using NanoString™ PanCancer Immune Profiling panel, consisting of 770 immunity-related genes describing 24 IME cell types. Immune Dysfunction and Exclusion (TIDE) scores were derived from an algorithm by Jiang et al.

RESULTS. Gp1 consisted of 183 AA and 752 EA, with median age older in EA (54.5 vs 59). On CIBERSORT IME analysis by race, AA had higher IME infiltrates including macrophages (Mp), dendritic cells (DC) and TILs; notably T regulatory (Treg) and T Follicular Helper (Tfh) cells. The ratios of Tregs and Tfh to total TILs were also elevated. When stratified by subtypes, AAs with TNBC/Basal-like BC had higher Tregs and Tfh cells. CD8+ cells were higher in HR+ and high-grade AA pts only. CD4+/total T-cells was higher in AA across all subtypes, and predicted worse OS (HR 3.15[1.07-9.2]). Gp2 had 190 AA and 177 EA with comparable median age at diagnosis (53 versus 54) and tumor grade. By subtype, TNBC had significantly higher total TILs, CD45+, CD8+, exhausted CD8+, Treg, cytotoxic T cells, B, natural killer (NK), activated NK, DC and Mp; yet significantly lower mast cells and neutrophils (p &lt;0.01). CD8+/Exhausted CD8+ and CD8+/Treg ratios were lower in TNBC and higher-grade tumors, and lowest in HR- grade III. Most of immune pathways were enriched in HR- tumors, with only exception being cell cycle genes being remarkably enriched in HR+ tissues (p &lt;0.01). TIDE demonstrated high immune dysfunction in HR- and high exclusion in HR+ tumors. When compared to EA, AA had more TILs, including B, cytotoxic T-cells, exhausted CD8+, NK, activated NK and Tregs (p &lt;0.01). Neutrophils, Mp and CD8+ were higher in EA. EA also had significantly higher ratio of immune cell types to total TILs across cytotoxic, exhausted CD8+ and Tregs, as well as persistent higher neutrophils, Mp and CD8+ ratios. CD8+/Treg ratio was higher in EA. Consistent with Gp1; CD4+/total T-cell ratio was higher in AA across all subtypes.

CONCLUSION. IME differed significantly by HR, grade and ancestry. Aggressive BC demonstrated stronger overall immune response but dysfunctional IME phenotype (higher Treg, lower granulocytes and mast cells ratios). AA had more TILs across all subtypes, but lower ratios of activator (CD8+, Cytotoxic) to suppressor TILs (Treg, exhausted CD8+), demonstrating immune tolerance and immune-desert model, exception being persistently high fraction of CD4+ ratio predicting worse OS.

Citation Format: Elkhanany A, Takabe K, Khoury T, Omilian A, Cheng D, Katsuta E, Davis W, Yan L, Hong C-C, Bandera E, Ambrosone C, Yao S. PanCancer profiling reveals population difference in breast cancer immune microenvironment [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-06-05.

Population genetic analyses of seven Chinese indigenous chicken breeds in a context of global breeds

Jiangxi province in China is rich in indigenous chicken breeds, which have diverse phenotypes and represent a valuable genetic resource for further genetic improvement of modern breeds. Here, we conducted a series of analyses to reveal genetic diversity, phylogenetic relationships and population structure of seven chicken breeds in Jiangxi province in the context of nine non-local chicken breeds, using 600K SNP data. We show that Jiangxi indigenous breeds have more abundant nucleotide diversity than do European local and commercial breeds. Among Jiangxi breeds, Dongxiang Blue-eggshell (DX) and Chongren Partride (CR) display remarkably reduced genetic diversity, as the two breeds exhibit increased inbreeding coefficients, runs of homozygosity, extent of linkage disequilibrium and reduced expected heterozygosity. DX, CR and Taihe Silkie (TH) represent three ancestral lineages of the Jiangxi chicken and display genetic differentiation from the other four Jiangxi breeds, which show a signature of admixture with European commercial breeds. These findings provide insight for the establishment of an efficient conservation program for Jiangxi chicken breeds. Considering the current status of genetic diversity and ancestral representativeness, particular attention should be paid to DX, CR and TH chickens.

Infection and recurrence rates of the C-QUR V-Patch™ in ventral hernia repairs

PURPOSE

Ventral hernias are a common surgical issue and a myriad of surgical mesh designs has been developed for their treatment. Many of these new mesh designs have not been extensively tested and their complications rates are largely unknown. The C-QUR V-Patch Mesh^™ combines a unique knit construction polypropylene mesh with an omega-3 fatty acid coating. There has only previously been one reported study investigating this mesh.

METHODS

A multicentre cohort study, with a single surgeon, of 168 consecutive patients with ventral hernias underwent repair using a standardized open pre-peritoneal approach with the novel C-QUR V-Patch Mesh^™ between January 2013 and June 2015. A median follow-up of 37 months was completed to assess the patients for hernia infection and recurrence rates. Mesh infections were further classified into early and late infections for further subgroup analysis.

RESULTS

Infection and recurrence rates of the C-QUR V-Patch^® were compared with similar published results of alternate mesh designs. Surgical site infection rates were 7.7% and recurrence rates were 2.4%. The infection rate rose dramatically to 19.0% when the mesh was placed intra-peritoneally. The rate of mesh explantation was 2.4% and usually occurred between 4 and 12 months post-operatively. Smoking was the only factor that appeared to be associated with recurrence.

CONCLUSION

This series finds that recurrence rates associated with the novel C-QUR V-Patch Mesh^™ is acceptably low; however, infection rates appear to be higher when compared to comparable products for use in ventral hernia repairs.

The Intrinsic Relationship Between Structure and Function of the Sialyltransferase ST8Sia Family Members

As a subset of glycosyltransferases, the family of sialyltransferases catalyze transfer of sialic acid (Sia) residues to terminal non-reducing positions on oligosaccharide chains of glycoproteins and glycolipids, utilizing CMP-Neu5Ac as the activated sugar nucleotide donor. In the four known sialyltransferase families (ST3Gal, ST6Gal, ST6GalNAc and ST8Sia), the ST8Sia family catalyzes synthesis of α2, 8-linked sialic/polysialic acid (polySia) chains according to their acceptor specificity. We have determined the 3D structural models of the ST8Sia family members, designated ST8Sia I (1), II(2), IV(4), V(5), and VI(6) using the Phyre2 server. Accuracy of these predicted models are based on the ST8Sia III crystal structure as the calculated template. The common structural features of these models are: (1) Their parallel templates and disulfide bonds are buried within the enzymes and are predominately surrounded by helices; (2) The anti-parallel β-sheets are located at the N-terminal region of the enzymes; (3) The mono-sialytransferases (mono-STs), ST8Sia I and ST8Sia VI, contain only a single pair of disulfide bonds, and there are no anti-parallel β-sheets in ST8Sia VI; (4) The Nterminal region of all of the mono-STs are located some distant away from their core structure; (5) These conformational features show that the 3D structures of the mono-STs are less compact than the two polySTs, ST8Sia II and ST8Sia IV, and the oligo-ST, ST8Sia III. These structural features relate to the catalytic specificity of the monoSTs; (6) In contrast, the more compact structural features of ST8Sia II, ST8Sia IV and ST8Sia III relate to their ability to catalyze the processive synthesis of oligo- (ST8Sia III) and polySia chains (ST8Sia II &amp; ST8Sia IV); (7) Although ST8Sia II, III and IV have similar conformations in their corresponding polysialyltransferase domain (PSTD) and polybasic region (PBR) motifs, the structure of ST8Sia III is less compact than ST8Sia II and ST8Sia IV, and the amino acid components of the several three-residue-loops in the two motifs of ST8Sia III are different from that in ST8Sia II and ST8Sia IV. This is likely the structural basis for why ST8Sia III is an oligoST and not able to polysialylate and; (8) In contrast, essentially all amino acids within the threeresidue- loops in the PSTD of ST8Sia II and ST8Sia IV are highly conserved, and many amino acids in the loops and the helices of these two motifs are critical for NCAM polysialylation, as determined by mutational analysis and confirmed by our recent NMR results. In summary, these new findings provide further insights into the molecular mechanisms underlying polyST-NCAM recognition, polySTpolySia/ oligoSia interactions, and polysialylation of NCAM.

3D-printed vascular networks direct therapeutic angiogenesis in ischaemia

Arterial bypass grafts remain the gold standard for the treatment of end-stage ischaemic disease. Yet patients unable to tolerate the cardiovascular stress of arterial surgery or those with unreconstructable disease would benefit from grafts that are able to induce therapeutic angiogenesis. Here, we introduce an approach whereby implantation of 3D-printed grafts containing endothelial-cell-lined lumens induces spontaneous, geometrically guided generation of collateral circulation in ischaemic settings. In rodent models of hind-limb ischaemia and myocardial infarction, we demonstrate that the vascular patches rescue perfusion of distal tissues, preventing capillary loss, muscle atrophy and loss of function. Inhibiting anastomoses between the construct and the host's local capillary beds, or implanting constructs with unpatterned endothelial cells, abrogates reperfusion. Our 3D-printed grafts constitute an efficient and scalable approach to engineer vascular patches able to guide rapid therapeutic angiogenesis and perfusion for the treatment of ischaemic diseases.