Whole-genome resequencing reveals genetic structure and introgression in Pudong White pigs

Pudong White (PDW) pigs, historically originating from Shanghai, are the only Chinese indigenous pigs characterised by their completely white coats, with the exception of Rongchang pigs. However, there is limited information concerning their overall genetic structure or relationship with other breeds, especially the East Chinese (ECN) and European pigs. To uncover the genetic structure, selection signatures, and potential exotic introgression in PDW pigs, we sampled 15 PDW pigs using whole-genome sequencing (~20×). We then conducted in-depth population genetic analyses in 320 pigs from 27 global pig groups, namely, European wild boars, Chinese wild boars, and outgroup. Neighbour-joining tree and principal component analysis confirmed that PDW pigs belonged to the ecotype of ECN pigs. Both f3, D-statistics, and structure analysis showed that PDW pigs shared apparent alleles with Large White (LW) pigs. Three statistics, rIBD, a haplotype heat map and copy number variation, further indicated that PDW pigs shared apparent alleles with LW pigs at the KIT Proto-Oncogene, Receptor Tyrosine Kinase (KIT) and PARG-MARCHF8 loci, suggesting that the lineage of European pigs in PDW originated from LW pigs. After further detecting the KIT mutations in different pig breeds, PDW was confirmed to have the same duplication region 1, duplication region 2, and the splicing mutation on intron 17 of KIT as LW pigs that determine the white coat colour phenotype in European white pigs. We hypothesised that LW pigs were imported to China ∼110-160 years ago according to the admixture time estimate and then crossed with ECN pigs, resulting in the introgression of the KIT alleles that produce the white coat colour phenotype in the PDW pig breed. To our knowledge, this study presents the first thorough description of the genetic structure of PDW pigs via whole-genome resequencing data; moreover, the results provide a basis for the national project for the conservation of this unique Chinese local population.

[Clinical and genetic studies on 76 patients with hydrocephalus caused by methylmalonic acidemia combined with homocysteinuria]

Objective: To analyze the clinical features, genetic characteristics, treatment and follow-up results of patients with hydrocephalus caused by methylmalonic acidemia combined with homocysteinuria, and to discuss the optimal strategies for assessing and treating such patients. Methods: From January 1998 to December 2020, 76 patients with hydrocephalus due to methylmalonic acidemia combined with homocysteinuria in the Department of Pediatrics in 11 hospitals including Peking University First Hospital were diagnosed by biochemical, genetic analysis and brain imaging examination. The patients were divided into operation-group and non-operation-group according to whether they underwent ventriculoperitoneal shunt. The clinical features, laboratory examinations, genotype, and follow-up data were retrospectively analyzed. Data were compared between the two groups using rank sum test, and categorical data were compared using χ² test. Results: Among the 76 patients (51 male, 25 female), 5 were detected by newborn screening, while 71 were diagnosed after clinical onset, 68 cases (96%) had early-onset, 3 cases (4%) had late-onset. The most common clinical manifestations of 74 cases with complete data were psychomotor retardation in 74 cases (100%), visual impairment in 74 cases (100%), epilepsy in 44 cases (59%), anemia in 31 cases (42%), hypotonia or hypertonia in 21 cases (28%), feeding difficulties in 19 cases (26%) and disturbance of consciousness in 17 cases (23%). Genetic analysis was performed in 76 cases, all of whom had MMACHC gene variations, including 30 homozygous variations of MMACHC c.609G>A. The most common variations were c.609G>A (94, 62.7%), followed by c.658_660del (18, 12.0%), c.567dupT (9, 6.0%) and c.217C>T (8, 5.3%). Therapy including cobalamin intramuscular injection, L-carnitine and betaine were initiated immediately after diagnosis. A ventriculoperitoneal shunt operation was performed in 41 cases (operation group), and 31 patients improved after metabolic intervention (non-operation group). There was no significant difference in the age of onset, the age of diagnosis, the blood total homocysteine, methionine, and urinary methylmalonic acid concentration between the two groups (all P>0.05). The symptoms of psychomotor development, epilepsy, and visual impairments improved gradually after a long-term follow-up in the operation group. Conclusions: Hydrocephalus is a severe complication of methylmalonic acidemia combined with homocysteinuria. The most common clinical manifestations are psychomotor retardation, visual impairment, and epilepsy. It usually occurs in early-onset patients. Early diagnosis and etiological treatment are very important. Hydrocephalus may improve after metabolic intervention in some patients. For patients with severe ventricular dilatation, prompt surgical intervention can improve the prognosis.

POS0332 ENDOTHELIAL ACTIVATION IN SYSTEMIC SCLEROSIS VASCULOPATHY: ROLE OF LONG NON-CODING RNA H19X

Background:

Long non-coding RNAs (lncRNA) are a class of non-coding transcripts which modulate many biological processes. Our previous studies showed that lncRNA H19X is pivotal in the regulation of TGFβ driven fibrosis in systemic sclerosis (SSc)1.

Objectives:

We aimed to investigate whether H19X plays a functional role in the regulation of endothelial cell (EC) activation, which is crucial in SSc vasculopathy2.

Methods:

Single-cell RNA sequencing (scRNA-seq) data from 27 dcSSc and 10 healthy control (HC) skin biopsies, following 10X Genomics partitioning and cDNA preparation, were analyzed for H19X expression in skin ECs, using Seurat package in R. A total of 4,981 ECs, of which 1,583 cells originated from HC and 3,398 cells originated from SSc patients, ranging from 59 to 342 ECs per subject, characterized by enrichment of EC markers of CLDN5, VWF and PECAM1.

Expression of H19X in Human Dermal Microvascular ECs (HDMEC) was analyzed by qPCR. HDMEC were stimulated with different proinflammatory cytokines including IFNα, IFNβ, IFNγ, TGFβ, TNFα, IL-6, IL-1β and IL-4 at biologically relevant concentrations. In order to ascertain its effect in ECs, H19X was silenced in HDMECs using locked nucleic acid antisense oligonucleotides (LNA GapmeRs). qPCR and Western Blot (WB) were used to analyze the effects of H19X downregulation on EC activation biomarkers.

Results:

scRNA-seq data showed that H19X was significantly upregulated in SSc compared to healthy ECs (p=0.0095). Based on the differentially expressed gene profiles among subclusters, EC were further annotated as arterial (SEMA3G, HEY1), capillary (CA4, RGCC), venous (ACKR1, VCAM1), lymphatic (PROX1, LYVE1) ECs, as well as two aberrant clusters, proliferating (TOP2A, MKI67) and injured (HSGP2, APLNR) ECs, which were dominated by the SSc ECs. Specifically, the highest expression of H19X was found in injured SSc ECs and capillary SSc ECs. Overall, 1.5% SSc EC, about 51 cells, expressed detectable levels of H19X.

In HDMEC (n=3), H19X was consistently induced by IFNα, IFNβ and IFNγ. Time curve analysis demonstrated that the strongest induction was observed at 48H (1.5±0.2, 1.6±0.4 and 2.1±0.3 – fold increase respectively). The combination of different IFNs determined stronger H19X induction after 48H stimulation, with a 2.4±0.1 increase with the combination of all IFNs and a 2.4±0.1 increase after the combination of IFNα+γ.

Importantly, H19X knockdown lead to consistent and significant decrease of mRNAs of several adhesion molecules, including VCAM1, E- Selectin and P-Selectin, both in untreated HDMEC and after IFN stimulation. A decrease of VCAM and P-Selectin could be also demonstrated with WB analysis. No change was seen in other EC activation markers, including endothelin-1 and angiogenesis markers including VEGF, VEGFRA, Tie2 and thrombospondin.

Conclusion:

This is the first report analyzing a potential role of lncRNA H19X in SSc vasculopathy. Our results suggest that lncRNA H19X could act as a regulator of adhesion molecules expression in EC, possibly mediated by IFNs, and be therefore involved in EC activation.

References:

[1]Pachera E, et al. Long noncoding RNA H19X is a key mediator of TGF-β-driven fibrosis. J Clin Invest. 2020 Sep 1;130(9):4888-4905.

[2]Mostmans Y, et al. The role of endothelial cells in the vasculopathy of systemic sclerosis: A systematic review. Autoimmun Rev. 2017 Aug;16(8):774-786.

Acknowledgements:

I have no acknowledgements to declare

Disclosure of Interests:

Francesca Tirelli: None declared, Elena Pachera: None declared, Robert Lafyatis Consultant of: RL served as a consultant with Bristol Meyers Squibb, Formation, Sanofi, Boehringer-Ingelheim, Merck, and Genentech/Roche, Acceleron, Grant/research support from: RL received grants form Bristol Meyer Squib, Corbus, Formation, Moderna, Regeneron, Pfizer, and Kiniksa, Menqi Huang: None declared, Francesco Zulian: None declared, Gabriela Kania: None declared, Oliver Distler Speakers bureau: Speaker fee on Scleroderma and related complications and on other rheumatology topics: Actelion, Bayer, Boehringer Ingelheim, Medscape, Novartis, Roche, Menarini, Mepha, MSD, iQone, Pfizer, Consultant of: Has consultancy relationship in the area of potential treatments for systemic sclerosis and its complications (last three years):Abbvie, Actelion, Acceleron Pharma, Amgen, AnaMar, Arxx Therapeutics, Bayer, Baecon Discovery, Blade Therapeutics, Boehringer, CSL Behring, ChemomAb, Corpuspharma, Curzion Pharmaceuticals, Ergonex, Galapagos NV, GSK, Glenmark Pharmaceuticals, Inventiva, Italfarmaco, iQvia, -Kymera, Medac, Medscape, Mitsubishi Tanabe Pharma, MSD, Roche, Sanofi, UCB, Lilly, Target BioScience, Pfizer. Consultancy relationship for rheumatology topic other than Scleroderma: Abbvie, Amgen, Lilly, Target BioScience, Pfizer. In addition, he holds a patent issued “mir-29 for the treatment of systemic sclerosis” (US8247389, EP2331143)., Grant/research support from: Has received grants/research support in the are of potential treatments for systemic sclerosis from Actelion, Bayer, Boehringer Ingelheim, Kymera Therapeutics, Mitsubishi Tanabe Pharma

Finite element evaluation of a simple model for elastic waves in strongly scattering elongated polycrystals

A simple semi-analytical model for longitudinal scattering-induced attenuation and phase velocity is proposed for strongly scattering cubic polycrystals with statistically elongated grains. It is formulated by iterating the Born approximation of the far-field approximation model and by empirically increasing the coefficient in the quadratic term for the elastic scattering factor. The comparison with the three-dimensional grain-scale finite element calculations shows excellent performance of the semi-analytical model for both attenuation and phase velocity in all studied frequency ranges and especially in the Rayleigh regime in which, for strongly scattering materials, the existing analytical models significantly disagree with the numerical results.

[The mechanism of HDAC6 in paraquat-induced autophagy dysfunction of dopaminergic neurons by mediating aggresome-autophagy-lysosomal pathway]

Objective: To explore the mechanism of HDAC6 mediated aggresome-autophagy-lysosome pathway in paraquat-induced autophagy in dopaminergic neurons. Methods: Human neuroblastoma cell (SH-SY5Y cell) was used as model of dopaminergic neurons in vitro. The cells were treated with terminal concentrations of 0, 25, 50, 100, 200 and 400μmol/L PQ for 24 hours, and the cells were induced by 100 μmol/L PQ for different time (0, 12, 24, 36, 48, 60 and 72 h) . Cell viability was detected by CCK-8 assay. The expression levels of HDAC6, α-syn, Dynein IC1/2, LC3, Beclin1, p62 and Lamp-1 were detected by Western blot. Immunofluorescence double-labeling method was used to observe the expression and localization of HDAC6, α-syn, Dynein IC1/2, LC3, Lamp-1 and γ-tubulin in cells. Results: CCK-8 assay showed PQ induced cell survival rate decrease in a time and dose dependent manner (R=-0.950、-0.960, P<0.05) .Western blot showed that compared with control group, the protein levels of HDAC6, α-syn, p62 in PQ-exposed group were significantly increased (P<0.05) , but there was a significant decrease in expression level of the ratio of autophagy-related protein LC3 Ⅱ/LC3 Ⅰ, Beclin1, Dynein IC1/2, Lamp-1in PQ-exposed group (P<0.05) . The results of immunofluorescence double-labeling showed that compared with the control group, the fluorescence signals of HDAC6 and α-syn in the PQ-exposed group increased, and the protein expression level increased, while the fluorescence signals of Dynein IC1/2, LC3, and Lamp-1 decreased. The protein expression level is reduced. HDAC6 gradually accumulates from the diffuse shape to the nucleus; Under normal circumstances, α-syn, Dynein IC1/2, γ-tubulin, LC3, and Lamp-1 are mainly distributed in the cytoplasm. After PQ is infected, they gather in the nucleus and co-localize with HDAC6 in the area around the nucleus. Conclusion: PQ may induce abnormal aggregation of α-syn by inducing HDAC6-mediated aggresome-autophagy-lysosomal pathway disorder.

Longitudinal wave attenuation in polycrystals with elongated grains: 3D numerical and analytical modeling

This work develops a second-order approximation (SOA) model and a three-dimensional (3D) finite element (FE) model to calculate scattering-induced attenuation for elastic wave propagation in polycrystals with elongated grains of arbitrary crystal symmetry. The SOA model accounts for some degree of multiple scattering, whereas the 3D FE model includes all scattering possibilities. The SOA model incorporates the accurate geometric two-point correlation function obtained from the FE material systems to enable comparative studies between the two models. Also, the analytical Rayleigh and stochastic asymptotes are presented to provide explicit insights into propagation behaviors. Quantitative agreement is found between the FE and analytical models for all evaluated cases. In particular, the FE simulations support the SOA model prediction that grain shape does not exert influence on attenuation in the Rayleigh regime and its effect emerges as frequency increases to the stochastic regime showing anisotropy in attenuation. This attenuation anisotropy intensifies with the increase in frequency, but it exhibits a complicated behavior as frequency transits into the geometric regime. Wavefield fluctuations captured from the FE simulations are provided to help observe these complex scattering behaviors. The proportionality of attenuation to elastic scattering factors is also quantitatively evaluated.

Effects of hsa_circ_0000711 expression level on proliferation and apoptosis of hepatoma cells

OBJECTIVE

To investigate the role of human serum albumin (hsa)_circular (circ)_0000711 in hepatocellular carcinoma (HCC). Circular ribonucleic acids (circRNAs) are proven in numerous studies to play crucial role in tumor biology, but their roles in HCC remain unknown to a great extent.

PATIENTS AND METHODS

The circRNA expression profile microarray was employed to screen differentially expressed circRNAs in tumor tissues and adjacent tissues from HCC patients, and Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR) assay was performed for further verification. Next, the target micro RNAs (miRNAs) and their messenger RNAs (mRNAs) of key circRNAs were predicted by bioinformatics software, and a circRNA-miRNA-mRNA regulatory network was constructed. Subsequently, KEGG and GO enrichment analyses were applied to predict the possible biological processes regulated by hsa_circ_0000711 and relevant signaling pathways. The miRNAs playing a key role in the circRNA-miRNA-mRNA regulatory network were then selected as the objects, and their direct binding to hsa_circ_0000711 was confirmed via luciferase reporter gene assay. Thereafter, hsa_circ_0000711 was overexpressed or knocked out, and the biological function of hsa_circ_0000711 was detected by cell counting kit-8 (CCK-8) assay, apoptosis detection, and 5-Ethynyl-2'-deoxyuridine (EdU) staining assay in vitro.

RESULTS

The results of expression profile screening revealed that there was a significant difference in the expression profile of circRNAs between tumor tissues and adjacent tissues in HCC patients. Based on the circRNA expression profile and RT-qPCR results, the expression level of hsa_circ_0000711 was overtly reduced in HCC tissues. In addition, miR-103a-3p had the highest eigenvector centrality in the circRNA-miRNA-mRNA regulatory network, suggesting that miR-103a-3p is a vital participant in the pathological mechanism of hsa_circ_0000711. The KEGG enrichment analysis results pointed out that the target genes regulated by hsa_circ_0000711 were clearly enriched in the tumor-associated signaling pathways. Besides, the results of GO enrichment analysis demonstrated that the biological processes regulated by hsa_circ_0000711 were mainly related to cell cycle regulation, so cell proliferation might be affected. The results of luciferase reporter gene and RT-qPCR assays showed that hsa_circ_0000711 directly bound to has-miR-103a-3p to serve as a molecular sponge. The results of CCK-8 and EdU staining assays revealed that the proliferation of hepatoma cells in hsa_circ_0000711 overexpression group was evidently enhanced. In addition, it was further found via flow cytometry that the apoptosis rate of cells was significantly raised in hsa_circ_0000711 low-expression group and dramatically declined in hsa_circ_0000711 overexpression group.

CONCLUSIONS

Overexpression of hsa_circ_0000711 promoted the proliferation and inhibited the apoptosis of hepatoma cells via targeting has-miR-103a-3p.

Construction of an MnO2 nanosheet array 3D integrated electrode for sensitive enzyme-free glucose sensing

MnO₂ based electrochemical enzyme-free glucose sensors remain significantly limited by their low electronic conductivity and associated complex preparation. In this paper, an MnO₂ nanosheet array supported on nickel foam (MnO₂ NS/NF) was prepared using a simple hydrothermal synthesis and employed as a 3D integrated electrode for enzyme-free glucose detection. It was found that MnO₂ NS/NF shows high performance with a wide linear range from 1 μM to 1.13 mM, a high sensitivity of 6.45 mA mM^-1 cm^-2, and a low detection limit of 0.5 μM (S/N = 3). Besides, MnO₂ NS/NF shows high selectivity against common interferences and good reliability for glucose detection in human serum. This work demonstrates the promising role of MnO₂ NS/NF as an efficient integrated electrode in enzyme-free glucose detection with high performance.

[Application of deep learning-based chest CT auxiliary diagnosis system in emergency trauma patients]

Objective: To investigate the diagnostic efficacy and potential application value of deep learning-based chest CT auxiliary diagnosis system in emergency trauma patients. Methods: A total of 403 patients, including 254 males and 149 females aged from 16 to 100 (50±19) years, who received emergency treatment for trauma and chest CT examination in the Eastern Theater General Hospital from September 2019 to November 2019 were retrospectively analyzed. Dr. Wise Lung Analyzer's chest CT auxiliary diagnosis system was applied to detect 5 types of injuries, including pneumothorax, pleural effusion/hemothorax, pulmonary contusion (shown as consolidation and ground glass opacity), rib fractures, and other fractures (including thoracic vertebrae, sternum, scapula and clavicle, etc.) and 6 other abnormalities (bullae, emphysema, pulmonary nodules, stripe, reticulation, pleural thickening). The diagnostic reference standards were labeled by two radiologists independently. The sensitivity and specificity of the auxiliary diagnosis system were evaluated. The imaging diagnostic reports were compared with the results of the auxiliary diagnosis system, and the diagnostic consistency between the two was calculated by using the Kappa test. Results: According to the reference standards, among the 403 patients, 29 were pneumothorax, 75 were pleural effusion/hemothorax, 131 were pulmonary contusion, 124 were rib fractures, and 63 were other fractures. The sensitivity and specificity of the auxiliary diagnosis system for detection of pneumothorax, pleural effusion/hemothorax, rib fractures, and other fractures were 96.6%, 97.6%, 80.0%, 99.7%, 99.2%, 83.9%, 84.1%, and 99.7%, respectively. The sensitivity of detecting lung contusion was 97.7%. There was a high consistency between the auxiliary diagnosis system and imaging diagnosis in the diagnosis of injuries, in which the kappa values of pneumothorax, pleural effusion, rib fracture and other fractures were 0.783, 0.821, 0.706 and 0.813, respectively (all P<0.001). Two cases of pneumothorax, three cases of pleural effusion/hemothorax, nine cases of rib fractures, and six cases of other fractures missed by imaging diagnosis were all detected by the auxiliary diagnosis system. The detection sensitivity of the auxiliary diagnosis system was higher for emphysema, pulmonary nodules and stripe (all>85%), but lower for bullae, reticulation and pleural thickening. Conclusions: The deep learning-based chest CT auxiliary diagnosis system could effectively assist chest CT to detect injuries in emergency trauma patients, which was expected to optimize the clinical workflow.

[Cathepsin L mediates glomerular endothelial cell injury by cleavaging complement C3 in trichloroethylene-sensitized mice]

Objective: To observe the expressions of complement 3 (C3) and endothelial cell injury-associated proteins before and after cathepsin L (CTSL) blockade in renal injury of trichloroethylene (TCE) -sensitized mice. Methods: In June 2018, 41 SPF female BALB/c mice were divided respectively into blank control group (n=5) , vehicle control group (n=5) , TCE group (n=15) and TCE+CTSLi group (n=16) to establish trichloroethylene-sensitized mice model by pretreating the mice with intraperitoneal injection of CTSL inhibitor (CTSLi) and using TCE for the first and last challenge. According to the skin sensitization score, the mice were divided into positive group and negative group. 72 hours after the last challenge, the renal function indexes of the mice were detected, the pathological changes of mice kidneys were observed, and the glomerular C3 and endothelial cell damage-related proteins [vascular cell adhesion molecule 1 (VCAM-1) , tight junction protein 5 (Claudin-5) and Syndecan-1] expression levels were detected. Results: The sensitization rates of mice in TCE group and TCE+CTSLi group were 53.3% (8/15) and 50.0% (8/16) , respectively, and there was no significant difference between the two groups (P>0.05) . Compared with vehicle control group and the corresponding TCE negative group, the serum creatinine (CRE) and blood urea nitrogen (BUN) levels of mice in the TCE positive group was increased, while the TCE positive group were higher than the TCE+CTSLi positive group (P<0.05) . Pathological examination showed obvious vacuolar degeneration and cellular edema in the mice kidney of the TCE positive group. In the TCE+CTSLi positive group, the above pathological damage was significantly improved. Immunohistochemical results showed that the expression of glomerular C3 fragment and VCAM-1 in TCE positive group were significantly higher than that of the vehicle control and TCE negative group (P<0.05) , while TCE+CTSLi positive group was significantly lower than that of TCE positive group (P<0.05) . Western blot test results showed that the relative expression levels of Claudin-5 and Syndecan-1 protein in the mice glomeruli of TCE positive group were significantly lower than those in the vehicle control group and TCE negative group (P<0.05) . Compared with the TCE positive group, the Claudin-5 protein was increased in the kidney of the TCE+CTSLi positive group, but the difference was not statistically significant (P>0.05) , while the Syndecan-1 protein was significantly increased in the TCE+CTSLi positive group (P<0.05) . Conclusion: CTSL may mediate the glomerular structural damage by cutting complement C3, activating the complement system, damaging endothelial cell structural protein Syndecan-1 and overexpressing adhesion molecule VCAM-1 in TCE-sensitized mice. Inhibiting the expression of CTSL may be an effective way to protect the glomerular integrity of structure and function in pharmacology.

Setting the new FRAX reference threshold without bone mineral density in Chinese postmenopausal women

PURPOSE

Despite the large number of osteoporosis patients in China, the diagnosis and treatment rates remain low. The Fracture Risk Assessment Tool (FRAX) can be used to effectively evaluate fracture risk. In this study, we explored the Chinese-specific thresholds of FRAX without the T-score.

METHODS

In all, 264 postmenopausal women aged > 50 years were randomly recruited from community-medical centers. All subjects completed self-reported questionnaires, BMD measurements, and spinal radiographs. The 10-year hip and major osteoporotic fracture risks were calculated by FRAX. A new threshold for both 10-year hip and major osteoporotic fracture risk was explored with receiver operating characteristic (ROC) curve analysis.

RESULTS

Overall, 92 subjects were diagnosed with osteoporosis. Among them, 14 participants with T-score > - 2.5 were diagnosed with osteoporosis based on clinical fractures. ROC analysis showed the cut-off value of the 10-year hip osteoporotic fracture for detecting osteoporosis was 0.95%, while that of 10-year major osteoporotic fracture was 4.95%. The sensitivity and specificity of the 10-year hip osteoporotic fracture probability for detecting osteoporosis were 0.86 and 0.59, respectively, while the guideline-recommended threshold had a sensitivity of 0.49 and specificity of 0.83. The sensitivity and specificity of the 10-year major osteoporotic fractures with the new threshold were 0.76 and 0.69, respectively, while the recommended threshold had a sensitivity of 0 and specificity of 1.

CONCLUSION

Current guideline-recommended FRAX thresholds without BMD showed low sensitivity. Therefore, 10-year osteoporotic hip fracture probability ≥ 0.95% and 10-year osteoporotic major fracture probability ≥ 4.95% are recommended as the new thresholds.

[Protective effects of taurine on neurons and microglia in Parkinson's disease-like mouse model induced by paraquat]

Objective: To investigate the protective effect of taurine (Tau) on hippocampus, substantia nigra neurons and microglia in paraquat (PQ) -induced Pakinson's disease-like mice. Methods: In April 2019, the specific pathogen free (SPF) C57BL/6 mice (n=36) were randomly divided into control group (NaCl) , Tau control group (150 mg/kg) , PQ exposure group (10 mg/kg PQ group, 15 mg/kg PQ group) , Tau intervention group (Tau+10 mg/kg PQ group, Tau+15 mg/kg PQ group) , respectively. Tau was used in 1 h before PQ administration for consecutive 6 weeks (twice per week) . General and neurobehavioral tests (Traction test, Open field test, Forced Swimming test, Tail suspension test, High plus maze and Object recognition test) were performed to test motor and cognitive function. After neuroethology detection, mice were euthanized and brains were collected. Nissl staining was used to detect the changes of the number and morphology of Nissl bodies in hippocampus and substantia nigra neurons of mice. Immunohistochemistry (IHC) was used to test the levels of neuron marker neuronal nuclei antigen (NeuN) , substantia nigra dopaminergic neuron marker tyrosine hydroxylase (TH) , α-synuclein (α-syn) , microglia markers ionized calcium bindingadaptor molecule-1 (Iba-1) , inducible nitric oxide synthase (iNOS) and interleukin-1β (IL-1β) in mice substantia nigra. The coexpression of Iba-1 and TH double-labeling, α-syn and TH double-labeling in mice substantia nigra were measured by immunofluorescence double staining. Results: General behavioral changes such as slow reaction and reduced action occurred in mice of PQ group. Compared with the control group, the scores of Traction test, and the time ratio of new object recognition in the PQ group decreased (P<0.05) , the fixed time of Swimming test and Tail suspension test increased (P<0.05) , the horizontal crawl number and vertical times of Open field test and the ratio of open arm residence time of High plus maze in the 15 mg/kg PQ group decreased (P<0.05) . Compared with the PQ group, the same dose of Tau+PQ group showed increased scores in Traction test (P<0.05) and decreased fixed time of Swimming test and Tail suspension test (P<0.05) . Compared with the 15 mg/kg PQ group, the horizontal crawl number of Open field test and the time ratio of new object recognition increased in the Tau+15 mg/kg PQ group (P<0.05) . Compared with the control group, the PQ group showed a decrease in the number of Nissl body in the hippocampus and substantia nigra (P<0.05) , a decrease in the number of NeuN and TH positive cells in the substantia nigra (P<0.05) , with a large number of α-syn deposition, Iba-1 activation of microglia cells, and an increase in the expression of inflammatory factors (IL-1β, iNOS) in the hippocampus and substantia nigra (P<0.05) . Compared with the PQ group, the same dose of Tau+PQ group showed the number of Nissl in the hippocampus and substantia nigra was significantly increased (P<0.05) , the number of NeuN and TH positive cells in the substantia nigra was significantly increased (P<0.05) , the expression levels of α-syn, Iba-1 and inflammatory factors (IL-1β, iNOS) in the substantia nigra were significantly decreased (P<0.05) . Conclusion: Tau could protect PQ-induced degeneration of substantia nigra dopaminergic neurons and hippocampal neuron loss by inhibiting the activation of microglia cells and release of inflammatory factors, and effectively improve the neurobehavioral and brain histopathological changes of PQ-induced PD-like mice.

Elastic wave velocity dispersion in polycrystals with elongated grains: Theoretical and numerical analysis

The phase velocity dispersion of longitudinal waves in polycrystals with elongated grains of arbitrary crystallographic symmetry is studied in all frequency ranges by the theoretical second-order approximation (SOA) and numerical three-dimensional finite element (FE) models. The SOA and FE models are found to be in excellent agreement for three studied polycrystals: cubic Al, Inconel, and a triclinic material system. A simple Born approximation for the velocity, not containing the Cauchy integrals, and the explicit analytical quasi-static velocity limit (Rayleigh asymptote) are derived. As confirmed by the FE simulations, the velocity limit provides an accurate velocity estimate in the low-frequency regime where the phase velocity is nearly constant on frequency; however, it exhibits dependence on the propagation angle. As frequency increases, the phase velocity increases towards the stochastic regime and then, with further frequency increase, behaves differently depending on the propagation direction. It remains nearly constant for the wave propagation in the direction of the smaller ellipsoidal grain radius and decreases in the grain elongation direction. In the Rayleigh and stochastic frequency regimes, the directional velocity change shows proportionalities to the two elastic scattering factors even for the polycrystal with the triclinic grain symmetry.

The association between napping and the risk of cardiovascular disease and all-cause mortality: a systematic review and dose-response meta-analysis

Background

Napping is a habit prevalent worldwide and occurs from an early age. Some sleep specialists have suggested it as a potential public health tool due to the prevalence of sleep disorder. However, the association between napping and the risk of cardiovascular disease (CVD) and all-cause mortality remains unclear.

Purpose

To assess the association between napping and the risk of CVD and all-cause mortality.

Methods

We conducted a systematic search of Medline, Embase and Cochrane databases from inception through December 2019 for prospective cohort studies investigating the association between napping and the risk of CVD and/or all-cause mortality. Overall estimates were calculated using random effect models with inverse variance weighting. Dose-response meta-analysis was performed using restricted cubic spline models. The results were reported as hazard ratio (HR) and 95% confidence interval (CI).

Results

A total of 313651 participants (57.8% female, 38.9% took naps) from 20 cohort studies were included in the analysis. Overall, pooled analysis detected no association between daytime nap and CVD (HR 1.13, 95% CI 0.99–1.28). However, in subgroup analysis including only participants who were female (HR 1.31, 95% CI 1.09–1.58), older (age&gt;65 years) (HR 1.36, 95% CI 1.07–1.72), or took a longer nap (nap time&gt;60 minutes) (HR 1.34, 95% CI 1.05–1.63), napping was significantly associated with a higher risk of CVD comparing to not napping. All-cause mortality was associated with napping overall (HR 1.19, 95% CI 1.12–1.26), and effect sizes were even more pronounced in females (HR 1.22, 95% CI 1.13–1.31), older participants (HR 1.27, 95% CI 1.11–1.45) and those who took a long nap (HR 1.30, 95% CI 1.12–1.47). Furthermore, after stratifying participants by night sleep time (&lt;6 and &gt;6h/day), no significant association was detected except those who slept &gt;6h/day at night and took a long nap (HR 1.13, 95% CI 1.03–1.24). Dose-response analysis showed a J-curve relation between nap time and CVD (Figure 1). The HR decreased from 0 to 25 min/day, followed by a sharp increase in the risk at longer times. A positive linear relationship between nap time and all-cause mortality was also observed.

Conclusion

Long napping over 60 minutes per day is associated with increased risks of CVD and all-cause mortality. Night sleep duration may play a role in the relation between napping and all-cause mortality. Further, large-scale prospective cohort studies need to confirm our conclusion and investigate the underlying mechanisms driving these associations.

Funding Acknowledgement

Type of funding source: None

Gen-editing to model Short QT syndrome type 5 using human-induced pluripotent stem cell-derived cardiomyocytes

Aims

Short QT syndrome (SQTS), a disorder associated with characteristic electrocardiogram QT-segment abbreviation, predisposes afflicted patients to sudden cardiac death. Despite some progress in assessing the organ level pathophysiology and genetic changes of the disorder, the understanding of the human cellular phenotype and discovering of an optimal therapy has lagged due to a lack of appropriate human cellular models of the disorder. The aim of this study was to establish a cellular model of SQTS type 5 using human-induced pluripotent stem cell–derived cardiomyocytes (hiPSC-CMs) and gene-edited cell line using CRISPR/CAS9.

Methods and results

This study recruited one patient with short QT syndrome type 5 carrying a mutation in CACNb2 gene as well as one healthy control subject. We generated hiPSCs from their skin fibroblasts, and differentiated hiPSCs into cardiomyocytes (hiPSC-CMs) for physiological. Isogenic control hiPSC-CMs generated by the CRISPR/CAS9 technique were also used for the study.

The hiPSC-CMs from the patient showed a reduced calcium current (ICa-L) density and shortened action potential duration (APD) compared with healthy control hiPSC-CMs and isogenic hiPSC-CMs. Furthermore, they demonstrated abnormal rhythmic activities. Carbachol increased the arrhythmic events in SQTS significantly but not in healthy and isogenic control cells. Gene and protein expression profiling showed a decreased CACNb2 expression in SQTS cells. Quinidine prolonged the APD and abolished arrhythmic activity.

Conclusions

Patient-specific hiPSC-CMs are able to recapitulate single-cell phenotype features of SQTS type 5 and provide novel opportunities to further elucidate the cellular disease mechanism and test drug effects.

Funding Acknowledgement

Type of funding source: None

Abscisic acid and hydrogen peroxide are involved in drought priming-induced drought tolerance in wheat (Triticum aestivum L.)

Drought is one of the major stress factors in wheat production on a global scale. Drought priming during the early growth stage can enhance drought tolerance in wheat (Triticum aestivum L.). Abscisic acid (ABA) and hydrogen peroxide (H₂ O₂ ) are important signal molecules in the adaptation of plants to drought stress. However, the roles of ABA and H₂ O₂ in drought priming-induced drought tolerance are not clear. In the present study, we evaluated the responses of wheat to an ABA inhibitor, H₂ O₂ scavenger and an inhibitor to investigate the (i) relationship between ABA and H₂ O₂ in osmotic adjustment after drought priming in the vegetative stage and (ii) responses to drought stress during grain filling. In the drought priming alone treatments, chemical application resulted in the scavenging of ABA and H₂ O₂ , weakening the alleviation effects of drought priming on drought stress, as demonstrated by the lower leaf water potential and grain yield. The ABA inhibitor completely inhibited accumulation of ABA and H₂ O₂ ; the ABA inhibitor inhibited respiratory burst oxidase homologue expression, whereas the H₂ O₂ inhibitor resulted in higher 9-cis-epoxycarotenoid dioxygenase expression and ABA concentration in primed plants, indicating that ABA scavenging inhibited H₂ O₂ biosynthesis while H₂ O₂ scavenging did not inhibit ABA biosynthesis. The results further demonstrated that NADPH oxidase-mediated H₂ O₂ production functions downstream of ABA, which induces osmolyte transcript expression and accumulation, and thus contributes to drought priming-induced stress tolerance. These results provide a theoretical basis for a better understanding of the mechanisms involved in drought priming-induced tolerance in wheat plants.

Maximizing the accuracy of finite element simulation of elastic wave propagation in polycrystals

Three-dimensional finite element (FE) modelling, with representation of materials at grain scale in realistic sample volumes, is capable of accurately describing elastic wave propagation and scattering within polycrystals. A broader and better future use of this FE method requires several important topics to be fully understood, and this work presents studies addressing this aim. The first topic concerns the determination of effective media parameters, namely, scattering induced attenuation and phase velocity, from measured coherent waves. This work evaluates two determination approaches, through-transmission and fitting, and it is found that these approaches are practically equivalent and can thus be used interchangeably. For the second topic of estimating modelling errors and uncertainties, this work performs thorough analytical and numerical studies to estimate those caused by both FE approximations and statistical considerations. It is demonstrated that the errors and uncertainties can be well suppressed by using a proper combination of modelling parameters. For the last topic of incorporating FE model information into theoretical models, this work presents elaborated investigations and shows that to improve agreement between the FE and theoretical models, the symmetry boundary conditions used in FE models need to be considered in the two-point correlation function, which is required by theoretical models.

Dental nerves: a neglected mediator of pulpitis

As one of the most densely innervated tissues, the dental pulp contains abundant nerve fibres, including sensory, sympathetic and parasympathetic nerve fibres. Studies in animal models and human patients with pulpitis have revealed distinct alterations in protein expression and histological appearance in all types of dental nerve fibres. Various molecules secreted by neurons, such as classical neurotransmitters, neuropeptides and amino acids, not only contribute to the induction, sensitization and maintenance of tooth pain, but also regulate non-neuronal cells, including fibroblasts, odontoblasts, immune cells and vascular endothelial cells. Dental nerves are particularly important for the microcirculatory and immune responses in pulpitis via their release of a variety of functional substances. Further, nerve fibres are found to be involved in dental soft and hard tissue repair. Thus, understanding how dental nerves participate in pulpitis could have important clinical ramifications for endodontic treatment. In this review, the roles of dental nerves in regulating pulpal inflammatory processes are highlighted and their implications for future research on this topic are discussed.