[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.