[Application of next-generation sequencing in the pathogenesis of uveal melanoma]

Uveal melanoma, as the most common intraocular malignant tumor in adults, has poor overall survival after metastasis. In recent years, next-generation sequencing technology has been increaingly applied in studying the genetic characteristics of diseases. From the perspectives of genome, epigenome, and transcriptome, this review summed up the genomics mutation, epigenomics regulation mechanism, and immune transcriptomic profiling of uveal melanoma in the context of next-generation sequencing technologies, especially chromosome copy number variation, gene mutation and DNA methylation.

[Application of isotemporal substitution model in epidemiological research]

Isotemporal substitution model is a powerful tool to explore the real association between physical behavior and health outcomes, which has the potential of the application in large-scale cohort study. This paper systematically introduces the principle of isotemporal substitution model and its implementation method in specific analysis to provide analytical ideas for the epidemiological research related to physical behavior in China. The baseline data of Regional Ethic Cohort Study in Northwest China conducted in Shaanxi province were used to analyze the relationship between physical behavior and cardiovascular disease with single-factor model, partition model and isotemporal substitution model. The advantages and disadvantages of different models were compared, and the advantages of isotemporal substitution model in quantifying physical activity health risk were introduced. Isotemporal substitution model could qualify physical behavior and health outcomes, which has wide application value in epidemiological research.

Diagnostic performance of angiography-derived index of microvascular resistance: a systematic review and pooled meta-analysis

Background

The index of microvascular resistance (IMR) is an established measurement of coronary microcirculation status. However, it has not been widely incorporated into routine practice due to need for intracoronary instrumentation (pressure wire) and hyperaemic agents. Several angiography-derived quantitative flow ratio-based indexes of microvascular resistance (angio-IMR) have been proposed rekindling the interest for the assessment and management of microvascular disease.

Purpose

To review the overall diagnostic accuracy of angio-IMR against wire based IMR.

Methods

A systematic review of the literature was performed and studies comparing angio-IMR with wire based IMR were included. Individual data was extracted using semi-automatic digitalization. Correlation of angio-IMR with IMR and its diagnostic performance against IMR were analysed.

Results

Six studies directly comparing angio-IMR with IMR were included. Data extraction rate was 85.1% (582/684 vessels). There was a linear correlation between angio-IMR and IMR (β=0.483, R square=0.298) (Figure 1A). Pooled sensitivity was 77%, specificity was 66%, positive predictive value was 65%, negative predictive value was 78%, and accuracy was 71.0%. Pooled area under receiver operator curve of angio-IMR for predicting IMR diagnosed coronary microvascular disease was 0.754 (95% confidential interval 0.715 to 0.793) (Figure 1B). Similar diagnostic performance was observed in subgroups of patients with or without ST-segment elevation myocardial infarction.

Conclusions

Currently available angio-IMR showed a clearly useful discrimination and diagnostic performance against the standard of wire based IMR.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): China Scholarship Council

Experimental Limits on Exotic Spin and Velocity Dependent Interactions Using Rotationally Modulated Source Masses and an Atomic-Magnetometer Array

Various theories beyond the standard model predict new interactions mediated by new light particles with very weak couplings to ordinary matter. Interactions between polarized electrons and unpolarized nucleons proportional to g_{V}^{N}g_{A}^{e}σ[over →]·v[over →] and g_{A}^{N}g_{A}^{e}σ[over →]·v[over →]×r[over →] are two such examples, where σ[over →] is the spin of the electrons, r[over →] and v[over →] are position and relative velocity between the polarized electrons and nucleons, g_{V}^{N}/g_{A}^{N} is the vector or axial-vector coupling constant of the nucleon, and g_{A}^{e} is the axial-vector coupling constant of the electron. Such interactions involving a vector or axial-vector coupling g_{V}^{N}/g_{A}^{N} at one vertex and an axial-vector coupling g_{A}^{e} at the polarized electron vertex can be induced by the exchange of spin-1 bosons. We report new experimental upper limits on such exotic spin-velocity-dependent interactions of the electron with nucleons from dedicated experiments based on a recently proposed scheme. We rotationally modulated two ∼6  Kg source masses at a frequency of 20 Hz. We used four identical atomic magnetometers in an array form to increase the statistics and cancel the common-mode noise. We applied a data processing method based on high precision numerical integration for the four harmonic frequencies of the signal. We reverse the rotation direction of the source masses to flip the signal due to the new interactions; thus, we can apply the [+1,-3,+3,-1] weighting method to remove possible slow drifting. Our constraint on the product of vector and axial-vector couplings is |g_{V}^{N}g_{A}^{e}|<2.1×10^{-34} and on the product of axial-vector and axial-vector couplings is |g_{A}^{N}g_{A}^{e}|<2.4×10^{-22} for an interaction range of 10 m. The new constraints on vector-axial-vector interaction improved by as much as more than 4 orders of magnitude and on axial-axial interaction by as much as 2 orders of magnitude in the corresponding interaction range, respectively.

B cell receptor signaling drives APOBEC3 expression via direct enhancer regulation in chronic lymphocytic leukemia B cells

Constitutively activated B cell receptor (BCR) signaling is a primary biological feature of chronic lymphocytic leukemia (CLL). The biological events controlled by BCR signaling in CLL are not fully understood and need investigation. Here, by analysis of the chromatin states and gene expression profiles of CLL B cells from patients before and after Bruton's tyrosine kinase inhibitor (BTKi) ibrutinib treatment, we show that BTKi treatment leads to a decreased expression of APOBEC3 family genes by regulating the activity of their enhancers. BTKi treatment reduces enrichment of enhancer marks (H3K4me1 and H3K27ac) and chromatin accessibility at putative APOBEC3 enhancers. CRISPR-Cas9 directed deletion or inhibition of the putative APOBEC3 enhancers leads to reduced APOBEC3 expression. We further find that transcription factor NFATc1 couples BCR signaling with the APOBEC3 enhancer activity to control APOBEC3 expression. We also find that enhancer-regulated APOBEC3 expression contributes to replication stress in malignant B cells. In total we demonstrate a novel mechanism for BTKi suppression of APOBEC3 expression via direct enhancer regulation in an NFATc1-dependent manner, implicating BCR signaling as a potential regulator of leukemic genomic instability.

[Progress in the treatment of refractory macular hole by human amniotic membrane]

The surgery of refractory macular hole is often very tough for its uncertain prognosis. There is no unified definition for refractory macular hole, which usually refers to macular hole with a long duration, large diameter, or failure of initial operation. Treatment success can be achieved in some cases by expanding the range of internal limiting membrane peeling or filling with autologous tissue. Human amniotic membrane is a kind of tissue with strong anti-inflammatory and anti-fibrosis effects, and has been widely used in the treatment of ocular surface diseases. In recent years, amniotic membrane has been used in treating refractory macular hole. Some positive results have been achieved, including improvement of postoperative macular structure and increase of visual function. This review focuses on the mechanism, efficacy and prospect of human amniotic membrane in the treatment of refractory macular hole, providing reference for clinical practice and research.

POS0458 ENRICHMENT OF COMPLEMENT, IMMUNOGLOBULINS, AND AUTOANTIBODY TARGETS IN THE PROTEOME OF PLATELETS FROM PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS (SLE)

Background

Systemic Lupus Erythematosus (SLE) is characterized by autoimmunity towards apoptotic/necrotic cells, complement activation and excessive amounts of circulating immune complexes. Platelets are recognized as immune cells that interacts with innate and adaptive immune functions. They are activated in SLE patients and contribute to an increased susceptibility to thrombosis [1]. Decreased platelet size has been observed in patients with SLE [2], but the mechanism(s) remains unclear. In this study, we have analyzed the complete proteome of platelets with normal and decreased size from SLE patients and from healthy controls (HC).

Objectives

Our aim was to find clues that could explain the morphological differences observed in platelets from SLE patients and to better characterize the role of platelets in SLE.

Methods

We included 23 consecutive patients with SLE, median SLEDAI-2K score was 2, and 10 HC. Blood count, serum complement levels and the presence of antiphospholipid or dsDNA antibodies were analyzed in all patients. Platelet size (forward scatter) and activation status (CD154, PAC1, CD32, PAR1, CD62P and Annexin V) was determined using flow cytometry. The proteome of 10 platelet isolates from SLE (five with smallest and the five with largest average size) and five HC were analyzed using liquid chromatography with tandem mass spectrometry (LC-MS/MS). Data were analyzed using ANOVA, t-test, hierarchical cluster analysis, protein interactions using the STRING software and correlation analysis using spearman correlation.

Results

We identified a total of 2572 proteins from the platelet isolates. Out of the identified proteins, 396 had significantly different levels, meeting an ANOVA q-value ≤ 0.01. Pairwise t-test analysis, using a fold difference (FD) of ≥ 1.5 and a p-value of ≤ 0.05 as cut off reveled significant differences in the distribution of proteins between groups. Platelets of both SLE groups (small and normal sized) shared higher levels of forty proteins and twenty proteins were reduced, compared to HC. Cytoskeletal functions were overrepresentation in the group of reduced proteins, while proteins with higher levels in platelets from SLE patients included proteins associated with complement and autoantibody targets such as Beta-2-glycoprotein 1, Annexin A5, and Prothrombin. Platelets from SLE patients also shared an abundance in immunoglobulin proteins, with even greater accumulation in the normal sized platelets. SLE platelet heavy constant alpha 1 (r -0.85, p=0.003), heavy constant mu (r -0.64, p=0.05) and heavy constant gamma 3 (r -0.80, p=0.008) was inversely correlated with complement C4 in serum and heavy constant gamma 2 (r -0.648, p=0.049) with complement C3.

Conclusion

This study revealed an accumulation of complement proteins, immunoglobulins and known autoantigens in platelets from SLE patients compared to HC. The signature was largely independent of platelet size, but the enrichment of proteins involved in SLE pathogenesis indicates that the composition is influenced by SLE disease mechanisms. This was supported by the inverse correlation between platelet immunoglobulin and serum levels of complement protein C3 and C4. Platelets are known to interact with complement and express the low-affinity immunoglobulin gamma Fc region receptor IIA (CD32), suggesting a role in the clearance of immune complexes [3]. Future studies will have to determine if platelets play a role in the turnover of complement and immune complexes and the potential role of platelets as a source of autoantigens.

References

[1]Linge, P., et al., The non-haemostatic role of platelets in systemic lupus erythematosus. Nat Rev Rheumatol, 2018. 14(4): p. 195-213.

[2]Lood, C., et al., Decreased platelet size is associated with platelet activation and anti-phospholipid syndrome in systemic lupus erythematosus. Rheumatology (Oxford), 2017. 56(3): p. 408-416.

[3]Huang, Z.Y., et al., Human platelet FcgammaRIIA and phagocytes in immune-complex clearance. Mol Immunol, 2011. 48(4): p. 691-6.

Disclosure of Interests

Petrus Linge: None declared, Andreas Jern: None declared, Helena Tydén: None declared, Birgitta Gullstrand: None declared, Hong Yan: None declared, Charlotte Welinder: None declared, Robin Kahn: None declared, Andreas Jonsen Consultant of: Astra Zeneca and glaxosmithkline, John Semple: None declared, Anders Bengtsson: None declared.

AB0933 Development and Validation of a Nomogram for Prediction of Nonalcoholic Fatty Liver Disease in Psoriatic arthritis

Background

Psoriatic arthritis (PsA) has been linked to an increased risk of metabolic syndrome (MetS). Non-alcoholic fatty liver disease (NAFLD), the hepatic manifestation of MetS, is now the commonest liver disease worldwide. About 65% of PsA patients suffer from NAFLD, and chronic systemic inflammation may be an important predisposing factor.

Objectives

The purpose of this study was to establish and validate a diagnostic model nomogram for predicting the occurrence of NAFLD in patients with PsA.

Methods

A total of 127 PsA patients (46 had NAFLD and 81 had no NAFLD) were enrolled in this study. Retrospectively collected clinical and serological parameters of these patients. The percentage and absolute number of lymphocytes and CD4+T cells were determined by Flow cytometry. The independent risk factors for NAFLD were screened in the PsA patients using univariate and multivariate binary logistic regression analyses and were used for construction of the nomogram prediction model. The AUROC (C index) was used to verify the model discrimination; the calibration curve and Hosmer-Lemeshow test were used to verify the model calibration; and the DCA curve was used to verify the clinical validity of the model.

Results

Univariate and multivariate logistic regression analyses showed that Body Mass Index (BMI) (OR=1.25, P=0.001), serum triglyceride (TG) (OR=3.51，P=0.015) and peripheral blood Th1 cell percentage (OR=1.12, P < 0.001) is an independent risk factor for NAFLD in PsA patients, and an individualized nomogram prediction model was successfully established. The prediction model had a good discrimination power with AUROC (C-index) of 0.83 (95% CI: 0.76-0.90); the P value in the Hosmer-Lemeshow test was 0.683, suggesting a high reliability of the predicted probability by the model; the DCA curve indicating a good clinical efficiency of the model.

Conclusion

Our study shows that the establishment of a nomogram prediction model of PsA complicated with NAFLD patients is helpful for early clinical screening and identification of such high-risk patients.

Figure 1.

A. Example of prediction nomogram for risk of PsA complicated with NAFLD patients; B. The ROC curve of the prediction model; C. The calibration curve of the prediction model; D. The decision curve analysis of the prediction model.

Disclosure of Interests

None declared

AB0506 PRELIMINARY STUDY ON IMBALANCE BETWEEN Th17 AND REGULATORY T CELLS IN ANTIPHOSPHOLIPID SYNDROME

Background

Antiphospholipid syndrome (APS) is a typical autoimmune disease, which can be classified into primary antiphospholipid syndrome (PAPS) and secondary antiphospholipid syndrome (SAPS) based on the presence or not of other autoimmune diseases. Disorders of peripheral blood lymphocyte and CD4+T cell subsets, especially Th17 and Treg cell subsets, may be involved in the pathogenesis of APS.

Objectives

To investigate the differences of peripheral blood lymphocyte and CD4+T cell subsets between patients with primary and secondary antiphospholipid syndrome and healthy controls, and to evaluate the correlation of antiphospholipid antibody titers and Th17/Treg values in PAPS and SAPS groups, as well as the correlation of cytokines and clinical characteristics in APS patients.

Methods

A total of 67 APS patients (12 PAPS patients, 55 SAPS patients) and 40 healthy controls were enrolled in this study. Retrospectively collected clinical and laboratory data of these patients. The absolute numbers of peripheral blood lymphocyte subsets and CD4+ T cell subsets were detected by flow cytometry, and serum cytokine levels were detected by flow cytometry bead array.

Results

Compared with healthy control group, the absolute values of T [689.26 vs. 1239.00, p＜0.001], B (104.69 vs. 177.50, p＜0.001), NK (98.97 vs. 300.00, p＜0.001) and CD4+T (330.16 vs. 628.50, p＜0.001) cells in SAPS group were decreased. While only the NK cells (151.30 vs. 300.00, p＝0.002) in the PAPS group were lower than that in healthy control group. However, the absolute values of T (1295.41 vs. 689.26, p＝0.001), B (184.44 vs. 104.69, p＝0.012), NK (151.30 vs. 98.97, p＝0.023) and CD4+T cells (698.34 vs. 330.16, p＝0.002) in PAPS group were significantly higher than those in SAPS group. For CD4+T cell subsets, PAPS patients and SAPS patients showed the same trend compared with healthy controls, showing increased Th1(111.50 vs. 23.47, p=0.002 and 71.43 vs. 23.47, p=0.001, respectively), decreased Th2(6.97vs.12.43, p=0.037 and 2.49 vs. 12.43, p＜0.001, respectively) and, more importantly, decreased Treg (18.77 vs. 29.53, p=0.031 and 12.01 vs. 29.53, p＜0.001, respectively), with increased Th17/Treg ratio (0.39 vs. 0.17, p=0.001 and 0.42 vs. 0.17, p＜0.001, respectively). Meanwhile, Th2(6.97 vs. 2.46, p＝0.006), Th17 (8.42 vs. 4.00, p＝0.042) and Treg (18.77 vs. 12.01, p＝0.020) cells in PAPS group were higher than those in SAPS group. As for the correlation study, we concluded that both aCL (r=0.6061, p=0.0405) and aβ2GPI (r=0.6900, p=0.0158) were positively correlated to Th17/Treg ratio in PAPS group. In addition, for APS patients, IL-2 (r=-0.420, p=0.010), IL-4 (r=-0.392, p=0.016), IL-10 (r=-0.331, p=-0.046), IL-17 (r=-0.479, p=0.006), and IFN-γ (r=-0.339, p=0.040) were negatively correlated with titers of aCL. And IL-6 is also associated with ESR (r=0.469, p=0.004) and CRP (r=0.670, p＜0.001).

Conclusion

Whether PAPS or SAPS patients, detection and balancing of lymphocyte and CD4+T subsets, especially Th17 and Treg subsets, may help correct immune disorders. Of course, the immune function of primary and secondary APS patients is not completely consistent, at least in terms of immune cells. Also, the role of cytokines in the pathogenesis of APS should not be ignored.

Figure 1.

Comparison of lymphocyte absolute values and CD4+ T cell subsets in PAPS group, SAPS group and healthy control group.

Figure 2.

The correlation analysis between the value of Th17/Treg and the titer of aCL and aβ2GPI in PAPS group and SAPS group, respectively.

Figure 3.

Heatmap of correlation of the serum cytokine levels of a variety of cytokines with clinical and laboratory characteristics of APS patients.

Disclosure of Interests

None declared

AB1073 HIGH INCIDENCE OF VIRUSES INFECTION IN CONNECTIVE TISSUE DISEASES PATIENTS

Background

Connective tissue diseases (CTDs) are a group of diseases with a variety of clinical manifestations. The main drug was glucocorticoids and immunosuppressive drugs, but the results are not satisfactory and the side effects are obvious, increased the incidence of infection, especially opportunistic infections. Infections becomes important causes of morbidity and mortality in CTD patients.

Objectives

To evaluate the incidence of infection in CTD patients who were clinically considered for co-infection by a combination of metagenomic next-generation sequencing (mNGS) and conventional diagnostic testing methods.

Methods

We analyzed 126 connective tissue diseases (CTD)patients with suspected infections admitted to The Second Hospital of Shanxi Medical University. All patients with CTD were diagnosed according to relevant diagnostic criteria, including 34 systemic lupus erythematosus (SLE), 24 dermatomyositis and polymyositis (DM/PM), 19 rheumatoid arthritis (RA), 10 undifferentiated connective tissue disease(UCTD),16 Sjogren syndrome (SS), 5 mixed connective tissue disease (MCTD), 5 ANCA associated systemtc vasculitis (AAV), 5 adult onset Stillystemtc isease disease(tic criteria, including 34nfections admitted to The Second Hospital of Shanxi (TA), 1 systemic sclerosis (SSC), 1retroperitoneal fibrosis (RPF). All enrolled patients were tested for conventional diagnostic testing methods(CDT) and mNGS.

Results

Among the 126 patients with CTD who were clinically considered for co-infection, 31 patients were negative for mNGS, and pathogens were detected in 99 of them. In our results, the mNGS and CDT were both positive for pathogens detection in 28 individuals.Of both positive individuals, 2 cases were perfect matches,12 cases were partly matched, 14 cases were totally mismatched. A total of 23 cases were negative for both mNGS and CDT. 70 cases were positive for mNGS only.There were only 5 cases positive for pathogens detection by CDT only. In addition, the results of mNGS showed that 131 patients were virus-positive(54%), 78 patients were prokaryotes-positive (37%) inculding bacteria, mycoplasma and 14 patients were eukaryotes-positive (9%). Of course, someones have mixed infections among these patinets some of these patients, with two or more pathogens. In the mixed infection, 5 cases have no viruses infection, 38 cases with virus infection, including 20 cases of bacteria and viruses infection, 4 cases of bacteria,fungi and viruses infection, 9 cases of viruses mixed infection, 1 case of bacteria,viruses,fungi and mycoplasma infection, 1 case of bacteria,viruses and mycoplasma infection, 1 case of viruses and mycoplasma infection, 1 case of viruses and fungi infection. According to the results, viruses were the most common pathogens identified, followed by prokaryotes and eukaryotes. It is noteworthy that the incidence of Human gammaherpesvirus 4(EBV), Human betaherpesvirus 5(CMV) and Human alphaherpesvirus 1 are more common in virus-positive. The most frequently detected prokaryotes were Acinetobacter baumannii, Mycobacterium tuberculosis complex, followed by Staphylococcus aureus, Prevotella melaninogenica,Staphylococcus homini and Helicobacter pylori. The major pathogens were Pneumocystis jirovecii and Candida albicans among eukaryotes-positive individuals.

Conclusion

As a complementary approach to conventional methods, mNGS could help improving the identification of infection in CTD patients.The incidence of viral infection is high in patients with connective tissue disease and close attention should be paid to it in clinical works.

Figure 1.

A. Comparison of test results between mNGS and conventional diagnostic testing methods(CDT) in CTD patients. B. The classification of mixed infections with or without viruses infection detected by mNGS and conventional diagnostic testing methods(CDT).

Figure 2.

Distribution of pathogens detected by mNGS. A. Type distribution of pathogens identified by mNGS. Species distribution of viruses of B.viruses, C.Prokayote, D. Eucayon detected by mNGS.

Disclosure of Interests

None declared

Fermented soybean meal increases nutrient digestibility via the improvement of intestinal function, anti-oxidative capacity and immune function of weaned pigs

The nutritional components of fermented soybean meal (FSBM) vary because of the complex process of microbial fermentation. The objective of this study was to investigate the nutritional value of FSBM from two sources and explore the mode of actions of FSBM on the improvement of nutrient digestibility with the measurements of digestive enzymes and serum biomarkers. Eight weaned barrows (initial BW: 14.12 ± 0.24 kg) equipped with T-cannula in the distal ileum were allotted to a duplicated 4 × 4 Latin-square design with four experimental diets and four periods. Four experimental diets included a soybean meal control diet, two FSBM diets, and a nitrogen-free diet. The two sources of FSBM increased the contents of CP, amino acid and lactic acid, while decreased the levels of anti-nutritional factors, including glycinin, β-conglycinin and trypsin inhibitors. Compared to soybean meal control diet, both FSBM diets significantly increased the apparent and standardised ileal digestibility of CP and amino acids (P < 0.05), increased the activities of lipase, maltase and invertase in digesta (P < 0.05), increased total antioxidant capacity, activities of glutathione peroxidase and superoxide dismutase, the levels of interleukin-4, IgA, IgG and IgM in serum (P < 0.05), while decreased the levels of diamine oxidase, malondialdehyde, interleukin-6, and interleukin-2 in serum (P < 0.05). Additionally, the standardised ileal digestibility of amino acids were highly correlated with the aforementioned digestive enzymes and health-related serum biomarkers. In summary, FSBM diets showed an improved nutritional value evidenced by the higher nutrient digestibility, which may be partially derived from its beneficial effects on intestinal integrity, anti-oxidative capacity and immune function.

Joint iterative reconstruction and 3D rigid alignment for X-ray tomography

X-ray tomography is widely used for three-dimensional structure determination in many areas of science, from the millimeter to the nanometer scale. The resolution and quality of the 3D reconstruction is limited by the availability of alignment parameters that correct for the mechanical shifts of the sample or sample stage for the images that constitute a scan. In this paper we describe an algorithm for marker-free, fully automated and accurately aligned and reconstructed X-ray tomography data. Our approach solves the tomographic reconstruction jointly with projection data alignment based on a rigid-body deformation model. We demonstrate the robustness of our method on both synthetic phantom and experimental data and show that our method is highly efficient in recovering relatively large alignment errors without prior knowledge of a low resolution approximation of the 3D structure or a reasonable estimate of alignment parameters.

Metastable dynamics of neural circuits and networks

Cortical neurons emit seemingly erratic trains of action potentials or "spikes," and neural network dynamics emerge from the coordinated spiking activity within neural circuits. These rich dynamics manifest themselves in a variety of patterns, which emerge spontaneously or in response to incoming activity produced by sensory inputs. In this Review, we focus on neural dynamics that is best understood as a sequence of repeated activations of a number of discrete hidden states. These transiently occupied states are termed "metastable" and have been linked to important sensory and cognitive functions. In the rodent gustatory cortex, for instance, metastable dynamics have been associated with stimulus coding, with states of expectation, and with decision making. In frontal, parietal, and motor areas of macaques, metastable activity has been related to behavioral performance, choice behavior, task difficulty, and attention. In this article, we review the experimental evidence for neural metastable dynamics together with theoretical approaches to the study of metastable activity in neural circuits. These approaches include (i) a theoretical framework based on non-equilibrium statistical physics for network dynamics; (ii) statistical approaches to extract information about metastable states from a variety of neural signals; and (iii) recent neural network approaches, informed by experimental results, to model the emergence of metastable dynamics. By discussing these topics, we aim to provide a cohesive view of how transitions between different states of activity may provide the neural underpinnings for essential functions such as perception, memory, expectation, or decision making, and more generally, how the study of metastable neural activity may advance our understanding of neural circuit function in health and disease.

RBBP4-p300 axis modulates expression of genes essential for cell survival and is a potential target for therapy in glioblastoma

BACKGROUND

RBBP4 activates transcription by histone acetylation, but the partner histone acetyltransferases are unknown. Thus, we investigated the hypothesis that RBBP4 interacts with p300 in a complex in glioblastoma (GBM).

METHODS

shRNA silencing of RBBP4 or p300 and RNAseq was used to identify genes co-regulated by RBBP4 and p300 in GBM43 patient-derived xenograft (PDX). RBBP4/p300 complex was demonstrated using proximity ligation assay (PLA) and ChIPseq delineated histone H3 acetylation and RBBP4/p300 complex binding in promoters/enhancers. Temozolomide (TMZ)-induced DNA double strand breaks (DSBs) were evaluated by γ-H2AX and proliferation by CyQuant and live cell monitoring assays. In vivo efficacy was based on survival of mice with orthotopic tumors.

RESULTS

shRBBP4 and shp300 downregulated 4768 genes among which 1485 (31%) were commonly downregulated by both shRNAs, while upregulated genes were 2484, including 863 (35%) common genes. The pro-survival genes were the top-ranked among the downregulated genes, including C-MYC. RBBP4/p300 complex was demonstrated in the nucleus, and shRBBP4 or shp300 significantly sensitized GBM cells to TMZ compared to the control shNT in vitro (P < .05). Moreover, TMZ significantly prolonged the survival of mice bearing GBM22-shRBBP4 orthotopic tumors compared with control shNT tumors (median shNT survival 52 days vs. median shRBBP4 319 days; P = .001). CREB-binding protein (CBP)/p300 inhibitor CPI-1612 suppressed H3K27Ac and RBBP4/p300 complex target proteins, including C-MYC, and synergistically sensitized TMZ in vitro. Pharmacodynamic evaluation confirmed brain penetration by CPI-1612 supporting further investigation to evaluate efficacy to sensitize TMZ.

CONCLUSIONS

RBBP4/p300 complex is present in GBM cells and is a potential therapeutic target.

[Associations between adverse childhood experiences and adulthood substance use among lesbians]

Objective: To investigate the associations between adverse childhood experiences (ACE) and substance use behaviors among lesbians to provide a scientific basis for high-risk population identification and formulation of targeted intervention measures. Methods: Lesbians who participated in routine AIDS voluntary counseling, testing services, activities, and peer recommendations were recruited from July to December 2018, with the help of LesPark in Beijing. Convenient sampling method was used. Demographic characteristics, ACE, and substance use behaviors of subjects were investigated using an online platform powered by www.wjx.cn. Subsequently, the associations between ACE and adulthood substance use behaviors were evaluated using the logistic regression model. The SPSS 22.0 was used for statistical analysis. Results: A total of 294 lesbians were recruited in the study, 81.3% (239/294) of them were lesbians, and 18.7% (55/294) were bisexuals. Besides, 55.8% (164/294) of subjects reported they had had ACE, with proportions of lesbians experiencing abuse, neglect, and family dysfunction as 33.3% (98/294), 24.5% (72/294), and 32.7% (96/294), respectively. 55.1% (162/294) of the lesbians reported they had smoked in the past 30 days, 11.2% (33/294) reported having drug-use behavior in the past three months, and 22.8% (67/294) claimed drinking alcohol weekly. Multivariate logistic regression analysis showed that lesbians with ACE were at high risks to smoke (OR=1.87, 95%CI: 1.13-3.08), drink (OR=2.13, 95%CI: 1.18-3.84), and use drugs (OR=3.33, 95%CI: 1.29-8.61) in adulthood. Moreover, lesbians with childhood family dysfunction were at higher risk of smoking cigarettes (OR=2.60, 95%CI: 1.46-4.62) and drinking alcohol (OR=2.65, 95%CI: 1.44-4.87). At the same time, those with abuse experience were at higher risk of drug use (OR=3.17, 95%CI: 1.26-7.96). Conclusions: Substance use behaviors, including cigarette smoking, drinking alcohol, and drugs use, were common among lesbians. Positive associations were found between ACE and adulthood substance use behaviors.

Treatment patterns and long-term persistence with osteoporosis therapies in women with Medicare fee-for-service (FFS) coverage

Osteoporosis, a chronic disease, requires long-term therapy. In Medicare-insured women, denosumab persistence was higher than oral bisphosphonate persistence over up to 3 years of follow-up. Longer-term persistence was higher among women who persisted in the first year of therapy.

INTRODUCTION

Osteoporosis, a chronic, progressive disease, requires long-term therapy; this study assessed long-term persistence with anti-resorptive therapies in postmenopausal women.

METHODS

This retrospective cohort study used administrative claims for women with data in the 100% Medicare osteoporosis sample who initiated (index date) denosumab, oral/intravenous (IV) bisphosphonate, or raloxifene between 2011 and 2014 and who had ≥ 1 year (zoledronic acid: 14 months) of pre-initiation medical/pharmacy coverage (baseline). Persistence was assessed from index date through end of continuous coverage, post-index evidence of censoring events (e.g., incident cancer), death, or end of study (December 31, 2015).

RESULTS

The study included 318,419 oral bisphosphonate users (78% alendronate), 145,056 denosumab users, 48,066 IV bisphosphonate users, and 31,400 raloxifene users; mean age ranged from 75.5 years (raloxifene) to 78.5 years (denosumab). In women with at least 36 months of follow-up (denosumab N = 25,107; oral bisphosphonates N = 79,710), more denosumab than oral bisphosphonate initiators were persistent at 1 year (73% vs. 39%), 2 years (50% vs. 25%), and 3 years (38% vs. 17%). Persistence decreased over time for all treatment groups, with denosumab users having the highest persistence in every follow-up time interval at or after 18 months. Women using denosumab, oral bisphosphonates, or raloxifene who persisted in a given year were more likely to remain persistent through the subsequent year.

CONCLUSIONS

Denosumab users persisted longer with therapy than women using other anti-resorptive medications, including oral bisphosphonates. Early persistence may predict long-term persistence. Overall persistence with osteoporosis medications is suboptimal and may impact fracture risk. Efforts to improve first year persistence are needed.