Kidney single-cell transcriptome profile reveals distinct response of proximal tubule cells to SGLT2i and ARB treatment in diabetic mice

Angiotensin receptor blockers (ARBs) and sodium-glucose cotransporter 2 inhibitors (SGLT2i) have been used as the standard therapy for patients with diabetic kidney disease (DKD). However, how these two drugs possess additive renoprotective effects remains unclear. Here, we conducted single-cell RNA sequencing to profile the kidney cell transcriptome of db/db mice treated with vehicle, ARBs, SGLT2i, or ARBs plus SGLT2i, using db/m mice as control. We identified 10 distinct clusters of kidney cells with predominant proximal tubular (PT) cells. We found that ARBs had more anti-inflammatory and anti-fibrotic effects, while SGLT2i affected more mitochondrial function in PT. We also identified a new PT subcluster, was increased in DKD, but reversed by the treatments. This new subcluster was also confirmed by immunostaining of mouse and human kidneys with DKD. Together, our study reveals kidney cell-specific gene signatures in response to ARBs and SGLT2i and identifies a new PT subcluster, which provides new insight into the pathogenesis of DKD.

Anti-Cancer Effects of Disulfiram in Cervical Cancer Cell Lines Are Mediated by Both Autophagy and Apoptosis

Disulfiram (DSF), which is used to treat alcohol dependence, has been reported to have anticancer effects in various malignant tumors. We studied the anti-cancer effects and mechanism of action of DSF on cervical cancer cell lines HeLa and SiHa. The anti-cancer effects of DSF were confirmed in vivo using a xenograft tumor model. The anti-cancer effects of DSF in human head and neck squamous cell carcinoma were found to be copper (Cu)-dependent. The anti-tumor effects of DSF/Cu were time- and dose-dependent and were mediated by both autophagy and apoptosis. DSF/Cu shows stronger cytotoxicity to adenocarcinoma cell lines with higher malignant behavior, and valosin-containing protein (VCP) is its potential target. The cytotoxic effect of DSF/Cu against cervical cancer cell lines in vitro was mediated by apoptosis and autophagy simultaneously. Analysis of the clinical relevance of DSF/Cu on a xenograft animal model showed that DSF markedly stimulated tumor necrosis. DSF may contribute to improved survival of patients with cervical cancer. The antitumor characteristic of DSF can be used in the development of a new drug for advanced and refractory patients with cervical cancer.

Blood transcriptomes of SARS-CoV-2 infected kidney transplant recipients demonstrate immune insufficiency

BACKGROUND

Kidney transplant recipients (KTRs) with COVID-19 have poor outcomes compared to non-KTRs. To provide insight into management of immunosuppression during acute illness, we studied immune signatures from the peripheral blood during and after COVID-19 infection from a multicenter KTR cohort.□.

METHODS

Clinical data were collected by chart review. PAXgene blood RNA was poly-A selected and RNA sequencing was performed to evaluate transcriptome changes.

RESULTS

A total of 64 cases of COVID-19 in KTRs were enrolled, including 31 acute cases (< 4 weeks from diagnosis) and 33 post-acute cases (>4 weeks). In the blood transcriptome of acute cases, we identified differentially expressed genes (DEGs) in positive or negative association COVID-19 severity scores. Functional enrichment analyses showed upregulation of neutrophil and innate immune pathways, but downregulation of T-cell and adaptive immune-activation pathways proportional to severity score. This finding was independent of lymphocyte count and despite reduction in immunosuppression (IS) in most KTRs. Comparison with post-acute cases showed "normalization" of these enriched pathways after >4 weeks, suggesting recovery of adaptive immune system activation despite reinstitution of IS. The latter analysis was adjusted for COVID-19 severity score and lymphocyte count. DEGs associated with worsening disease severity in a non-KTR cohort with COVID-19 (GSE152418) showed significant overlap with KTRs in these identified enriched pathways.

CONCLUSION

Blood transcriptome of KTRs affected by COVID-19 shows decrease in T-cell and adaptive immune activation pathways during acute disease that associate with severity despite IS reduction and show recovery after acute illness.

SIGNIFICANCE STATEMENT

Kidney transplant recipients (KTRs) are reported to have worse outcomes with COVID-19, and empiric reduction of maintenance immunosuppression is pursued. Surprisingly, reported rates of acute rejection have been low despite reduced immunosuppression. We evaluated the peripheral blood transcriptome of 64 KTRs either during or after acute COVID-19. We identified transcriptomic signatures consistent with suppression of adaptive T-cell responses which significantly associated with disease severity and showed evidence of recovery after acute disease, even after adjustment for lymphocyte number. Our transcriptomic findings of immune-insufficiency during acute COVID-19 provide an explanation for the low rates of acute rejection in KTRs despite reduced immunosuppression. Our data support the approach of temporarily reducing T -cell-directed immunosuppression in KTRs with acute COVID-19.

Bevacizumab's association with a decreased risk of brain metastases in ECOG-ACRIN E1505, a phase III randomized trial of adjuvant chemotherapy with or without bevacizumab in surgically-resected NSCLC

Introduction

ECOG-ACRIN E1505 was a phase 3 randomized trial of adjuvant chemotherapy with or without bevacizumab for patients with stages IB (>4 cm) to IIIA NSCLC. We sought to estimate the incidence and risk factors for brain recurrence as compared with extracranial recurrences (ECRs).

Methods

ECOG-ACRIN E1505 noted that bevacizumab failed to improve overall survival (OS) (OS hazard ratio [HR] = 0.99 [0·82–1·19], p = 0.90) or recurrence-free survival when added to chemotherapy in the adjuvant setting. The cumulative incidence of brain/ECR was estimated after adjusting for recurrence at other sites and death as competing events. A multivariable regression model was fitted using competing risk analysis to evaluate the effect of covariates on brain recurrence incidence.

Results

Median follow-up was 50.4 months. Among the 1501 patients enrolled, 472 developed ECR. There were 122 patients who had recurrence in the brain with or without simultaneous ECR as the first recurrence site (all-brain recurrences [ABRs]), and 84 of those with ABRs had recurrence in the brain only (isolated-brain recurrence [IBR]). The incidence of ABR, IBR, and ECR at 6 years was 9.9%, 5.9%, and 38.8%, respectively. Chemotherapy plus bevacizumab was associated with a decreased incidence of ABR (HR = 0.64, p = 0.02) and IBR (HR = 0.62, p = 0.032), but there was no significant trend for an OS decrement in the bevacizumab arm versus the control arm for both ABR and IBR. Median survivals associated with IBR, ABR, and ECR were 9.5, 9.5, and 14.1 months, respectively. Nonsquamous histology (HR = 1.87, p = 0.003) was also associated with ABR. ECR was associated with nonsquamous NSCLC histology (HR = 1.79, p < 0.01) and stage/N2 involvement (HR = 1.13/1.37, both p < 0.01).

Conclusions

The addition of bevacizumab to chemotherapy was associated with reduction in brain recurrences, but not ECR. Brain metastases whether isolated or not are associated with a lower median survival than ECR and unlike ECR are not associated with traditional staging variables.

Shape variability of the central sulcus in the developing brain: a longitudinal descriptive and predictive study in preterm infants

Despite growing evidence of links between sulcation and function in the adult brain, the folding dynamics, occurring mostly before normal-term-birth, is vastly unknown. Looking into the development of cortical sulci in infants can give us keys to address fundamental questions: what is the sulcal shape variability in the developing brain? When are the shape features encoded? How are these morphological parameters related to further functional development? In this study, we aimed to investigate the shape variability of the developing central sulcus, which is the frontier between the primary somatosensory and motor cortices. We studied a cohort of 71 extremely preterm infants scanned twice using MRI - once around 30 weeks post-menstrual age (w PMA) and once at term-equivalent age, around 40w PMA -, in order to quantify the sulcus's shape variability using manifold learning, regardless of age-group or hemisphere. We then used these shape descriptors to evaluate the sulcus's variability at both ages and to assess hemispheric and age-group specificities. This led us to propose a description of ten shape features capturing the variability in the central sulcus of preterm infants. Our results suggested that most of these features (8/10) are encoded as early as 30w PMA. We unprecedentedly observed hemispheric asymmetries at both ages, and the one captured at term-equivalent age seems to correspond with the asymmetry pattern previously reported in adults. We further trained classifiers in order to explore the predictive value of these shape features on manual performance at 5 years of age (handedness and fine motor outcome). The central sulcus's shape alone showed a limited but relevant predictive capacity in both cases. The study of sulcal shape features during early neurodevelopment may participate to a better comprehension of the complex links between morphological and functional organization of the developing brain.

Prognostic value of the platelet-to-lymphocyte ratio for outcomes of stroke: a systematic review and meta-analysis

OBJECTIVE

The current study aimed to conduct a systematic literature search and pool data from individual studies to assess the relationship between platelet-lymphocyte ratio (PLR) and functional outcomes and mortality in stroke patients.

MATERIALS AND METHODS

The databases of PubMed, Embase and Google Scholar were searched for relevant studies up to 21st August 2021. Odds ratios (OR) with 95% confidence intervals (CI) were calculated for the association between PLR and poor functional outcomes and mortality.

RESULTS

Sixteen studies were included in the systematic review and nine in the meta-analysis. On analysis of eight studies, we noted no statistically significant relationship between PLR and poor functional outcomes in patients with stroke (OR: 1.00 95% CI: 1.00, 1.00 I2=80% p=0.30). Data on mortality was reported by just two studies. Pooled analysis indicated no statistical relationship between PLR and mortality in patients with stroke (OR: 1.49 95% CI: 0.56, 3.98 I2=76% p=0.43). Descriptive analysis of the remaining studies demonstrated conflicting results for the relationship between PLR and early neurological deterioration (END) and functional outcomes.

CONCLUSIONS

Our results indicate that PLR may not be a useful prognostic marker to predict functional outcomes after AIS. Evidence on the predictive power of PLR for mortality and END after stroke is scarce and contrasting. There is a need for further studies assessing the role of PLR in predicting outcomes of stroke patients while taking into account important confounders like baseline stroke severity and treatment modality.

Deep learning identified pathological abnormalities predictive of graft loss in kidney transplant biopsies

Interstitial fibrosis, tubular atrophy, and inflammation are major contributors to kidney allograft failure. Here we sought an objective, quantitative pathological assessment of these lesions to improve predictive utility and constructed a deep-learning-based pipeline recognizing normal vs. abnormal kidney tissue compartments and mononuclear leukocyte infiltrates. Periodic acid- Schiff stained slides of transplant biopsies (60 training and 33 testing) were used to quantify pathological lesions specific for interstitium, tubules and mononuclear leukocyte infiltration. The pipeline was applied to the whole slide images from 789 transplant biopsies (478 baseline [pre-implantation] and 311 post-transplant 12-month protocol biopsies) in two independent cohorts (GoCAR: 404 patients, AUSCAD: 212 patients) of transplant recipients to correlate composite lesion features with graft loss. Our model accurately recognized kidney tissue compartments and mononuclear leukocytes. The digital features significantly correlated with revised Banff 2007 scores but were more sensitive to subtle pathological changes below the thresholds in the Banff scores. The Interstitial and Tubular Abnormality Score (ITAS) in baseline samples was highly predictive of one-year graft loss, while a Composite Damage Score in 12-month post-transplant protocol biopsies predicted later graft loss. ITASs and Composite Damage Scores outperformed Banff scores or clinical predictors with superior graft loss prediction accuracy. High/intermediate risk groups stratified by ITASs or Composite Damage Scores also demonstrated significantly higher incidence of estimated glomerular filtration rate decline and subsequent graft damage. Thus, our deep-learning approach accurately detected and quantified pathological lesions from baseline or post-transplant biopsies and demonstrated superior ability for prediction of post-transplant graft loss with potential application as a prevention, risk stratification or monitoring tool.

Probing Gluon Spin-Momentum Correlations in Transversely Polarized Protons through Midrapidity Isolated Direct Photons in p^{↑}+p Collisions at sqrt[s]=200 GeV

Studying spin-momentum correlations in hadronic collisions offers a glimpse into a three-dimensional picture of proton structure. The transverse single-spin asymmetry for midrapidity isolated direct photons in p^{↑}+p collisions at sqrt[s]=200  GeV is measured with the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). Because direct photons in particular are produced from the hard scattering and do not interact via the strong force, this measurement is a clean probe of initial-state spin-momentum correlations inside the proton and is in particular sensitive to gluon interference effects within the proton. This is the first time direct photons have been used as a probe of spin-momentum correlations at RHIC. The uncertainties on the results are a 50-fold improvement with respect to those of the one prior measurement for the same observable, from the Fermilab E704 experiment. These results constrain gluon spin-momentum correlations in transversely polarized protons.

First-phase ejection fraction, a measure of pre-clinical heart failure, is strongly associated with increased mortality in patients with COVID-19

Introduction

Presence of heart failure is associated with a poor prognosis in patients with COVID-19. The aim of the present study was to examine whether first-phase ejection fraction (EF1), the ejection fraction measured in early systole up to the time of peak aortic velocity, a sensitive measure of pre-clinical heart failure, is associated with survival in patients hospitalised with COVID-19.

Methods

A retrospective outcome study was performed in patients hospitalised with COVID-19 who underwent echocardiography (n=380) at the West Branch of the Union Hospital, Wuhan, China and in patients admitted to King's Health Partners in South London UK. Association of EF1 with survival was performed using Cox proportional hazards regression. EF1 was compared in patients with COVID-19 and in historical controls with similar co-morbidities (n=266) who had undergone echocardiography before the COVID-19 pandemic.

Results

In patients with COVID-19, EF1 was a strong predictor of survival in each patient group (Wuhan and London). In the combined group, EF1 was a stronger predictor of survival than other clinical, laboratory and echocardiographic characteristics including age, co-morbidities and biochemical markers (figure 1). A cut-off value of 25% for EF1 gave a hazard ratio of 5.23 (95% CI: 2.85–9.60, p<0.001) unadjusted and 4.83 (95% CI: 2.35–9.95, p<0.001) when adjusted for demographics, co-morbidities, hs-cTnI and CRP (figure 2). EF1 was similar in patients with and without COVID-19 (23.2±7.3 vs 22.0±7.6%, p=0.092, adjusted for prevalence of risk factors and co-morbidities).

Conclusion

Impaired first-phase ejection fraction is strongly associated with mortality in COVID-19 and probably reflects pre-existing, pre-clinical heart failure.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Institute for Health Research (NIHR) UKBritish Heart Foundation (BHF) UK

Recipient APOL1 risk alleles associate with death-censored renal allograft survival and rejection episodes

Apolipoprotein L1 (APOL1) risk-alleles in donor kidneys associate with graft loss but whether recipient risk-allele expression impacts transplant outcomes is unclear. To test whether recipient APOL1 risk-alleles independently correlate with transplant outcomes, we analyzed genome-wide SNP genotyping data of donors and recipients from two kidney transplant cohorts, Genomics of Chronic Allograft Rejection (GOCAR) and Clinical Trials in Organ Transplantation (CTOT1/17). We estimated genetic ancestry (quantified as proportion of African ancestry or pAFR) by ADMIXTURE and correlated APOL1 genotypes and pAFR with outcomes. In the GOCAR discovery set, we observed that the number of recipient APOL1 G1/G2 alleles (R-nAPOL1) associated with increased risk of death-censored allograft loss (DCAL), independent of ancestry (HR = 2.14; P = 0.006), and within the subgroup of African American and Hispanic (AA/H) recipients (HR = 2.36; P = 0.003). R-nAPOL1 also associated with increased risk of any T cell-mediated rejection (TCMR) event. These associations were validated in CTOT1/17. Ex vivo studies of peripheral blood mononuclear cells revealed unanticipated high APOL1 expression in activated CD4+/CD8+ T cells and natural killer cells. We detected enriched immune response gene pathways in risk-allele carriers vs. non-carriers on the kidney transplant waitlist and among healthy controls. Our findings demonstrate an immunomodulatory role for recipient APOL1 risk-alleles associating with TCMR and DCAL. This finding has broader implications for immune mediated injury to native kidneys.

MAP2 is differentially phosphorylated in schizophrenia, altering its function

Schizophrenia (Sz) is a highly polygenic disorder, with common, rare, and structural variants each contributing only a small fraction of overall disease risk. Thus, there is a need to identify downstream points of convergence that can be targeted with therapeutics. Reduction of microtubule-associated protein 2 (MAP2) immunoreactivity (MAP2-IR) is present in individuals with Sz, despite no change in MAP2 protein levels. MAP2 is phosphorylated downstream of multiple receptors and kinases identified as Sz risk genes, altering its immunoreactivity and function. Using an unbiased phosphoproteomics approach, we quantified 18 MAP2 phosphopeptides, 9 of which were significantly altered in Sz subjects. Network analysis grouped MAP2 phosphopeptides into three modules, each with a distinct relationship to dendritic spine loss, synaptic protein levels, and clinical function in Sz subjects. We then investigated the most hyperphosphorylated site in Sz, phosphoserine1782 (pS1782). Computational modeling predicted phosphorylation of S1782 reduces binding of MAP2 to microtubules, which was confirmed experimentally. We generated a transgenic mouse containing a phosphomimetic mutation at S1782 (S1782E) and found reductions in basilar dendritic length and complexity along with reduced spine density. Because only a limited number of MAP2 interacting proteins have been previously identified, we combined co-immunoprecipitation with mass spectrometry to characterize the MAP2 interactome in mouse brain. The MAP2 interactome was enriched for proteins involved in protein translation. These associations were shown to be functional as overexpression of wild type and phosphomimetic MAP2 reduced protein synthesis in vitro. Finally, we found that Sz subjects with low MAP2-IR had reductions in the levels of synaptic proteins relative to nonpsychiatric control (NPC) subjects and to Sz subjects with normal and MAP2-IR, and this same pattern was recapitulated in S1782E mice. These findings suggest a new conceptual framework for Sz-that a large proportion of individuals have a "MAP2opathy"-in which MAP function is altered by phosphorylation, leading to impairments of neuronal structure, synaptic protein synthesis, and function.

[1-deoxynojirimycin alleviates liver fibrosis induced by type 2 diabetes in mice]

OBJECTIVE

To investigate the effect of 1-deoxynojirimycin (DNJ) for improving diabetic liver fibrosis and explore the underlying mechanism.

METHODS

Mouse models of type 2 diabetes were established in 10 Kunming mice by high-fat diet feeding for 8 weeks and intraperitoneal injection of STZ, with 5 mice receiving intraperitoneal injection of citrate buffer solution with normal feeding as the control group. The mouse models were randomized into two groups (n=5) for further highfat feeding (model group) and additional treatment with 10% DNJ in drinking water (200 mg · kg^-1 per day; DNJ group) for 8 weeks. The mice were monitored for changes in body weight (BW), blood glucose, serum total cholesterol (TC), triglyceride (TG) and superoxide dismutase (SOD) levels. The pathological changes in the liver tissue were observed using HE and Sirius Red staining, and the solubility of collagens in the liver tissues was determined. The expression levels of MCP-1, TNF-α, IL-1β and TGF-β1 mRNA were detected with real-time PCR, and the protein expressions of α-SMA and collagen2 (ColA2) were determined with Western blotting. In the in vitro experiment, mouse fibroblasts L929 cells were pretreated with DNJ (10 μg/ mL) or PBS for 30 min followed by culture in high-glucose medium for 24 h, and the level of ROS production was measured using dihydroethidium (DHE) staining.

RESULTS

In the mouse model of type 2 diabetes, DNJ treatment significantly lowered serum level of glucose, TC, and TG (P < 0.05) and increased serum SOD activity (P < 0.05). DNJ obviously attenuated liver fibrosis in the diabetic mice, as shown by alleviated cross-linking of collagens and reduced contents of pepsin-solubilized collagen (PSC) and total collagen (P < 0.05). DNJ treatment also significantly reduced the overexpression of the proinflammatory cytokines and fibrosis-related cytokines induced by diabetes (P < 0.05). In L929 cells exposed to high glucose, pretreatment with DNJ significantly lowered the intensity of red fluorescence in DHE staining.

CONCLUSION

DNJ can attenuate type 2 diabetes-induced liver fibrosis in mice through its hypoglycemic, anti-inflammatory and anti-oxidative effects.

[TRIM59 regulates invasion and migration of nasopharyngeal carcinoma cells by targeted modulation of PPM1B]

OBJECTIVE

To investigate whether TRIM59 regulates invasion and metastasis of nasopharyngeal carcinoma cells by targeting PPM1B.

METHOD

We analyzed the expression of TRIM59 in nasopharyngeal carcinoma tissues based on data from TCGA database and detected the expressions of TRIM59 and PPM1B in nasopharyngeal carcinoma and adjacent tissues using Western blotting. We also detected the expressions of TRIM59 and PPM1B at both the mRNA and protein levels in nasopharyngeal carcinoma cell lines using RT-PCR and Western blotting. Stable cell lines with TRIM59 overexpression or knockdown were established in HNE1 cells, in which the targeting relationship between TRIM59 and PPM1B was analyzed using Western blotting and a luciferase reporter gene assay. Transwell chamber assay was used to assess changes in the invasion and migration abilities of HNE1 cells with TRIM59 overexpression or knockdown.

RESULTS

Analysis based on TCGA database showed that TRIM59 expression was significantly higher in nasopharyngeal carcinoma tissues than in adjacent tissues (P=0.006); the expression of TRIM59 increased (P=0.01) and PPM1B expression decreased significantly (P=0.03) in nasopharyngeal carcinoma tissues. Compared with HNEpC cells, HNE1 cells expressed a significantly higher level of TRIM59 (P=0.04) but a lower level of PPM1B (P=0.01). Luciferase reporter gene assay indicated that PPM1B was a downstream target gene of TRIM59 and its expression was negatively correlated with TRIM59 expression (P=0.01). In HNE1 cells, TRIM59 overexpression significantly promoted cell invasion (P=0.01) and migration (P=0.02) while TRIM59 knockdown obviously suppressed cell invasion (P=0.01) and migration (P=0.01). TRIM59 knockdown with simultaneous PPM1B overexpression more strongly inhibited invasion (P=0.02) and migration (P=0.01) of HNE1 cells as compared with TRIM59 knockdown alone.

CONCLUSION

TRIM59 regulates invasion and migration of nasopharyngeal carcinoma cells through targeted modulation of PPM1B.

[Role of long noncoding RNA SNHG3 in regulating proliferation, migration and invasion of cervical cancer SiHa cells]

OBJECTIVE

To investigate the regulatory role of the long non-coding RNA (lncRNA) small nucleolar host gene 3 (SNHG3) in proliferation, migration and invasion of human cervical cancer cell line SiHa.

OBJECTIVE

Array data were retrieved from GEO database to analyze the expression levels of SNHG3 in cervical cancer and adjacent normal tissues. SiHa cells were transfected with a small interfering RNA (siRNA) targeting SNHG3, and the changes in the transcriptional levels of lncRNA SNHG3 and the epithelial-mesenchymal transition (EMT) markers N-cadherin, Snail, vimentin and E-cadherin were detected using real-time quantitative PCR; the protein expressions of N-cadherin, Snail, vimentin and E-cadherin were determined using Western blotting. Cell counting kit-8 (CCK8) assay was utilized to assess the proliferation capacity of the transfected cells. Wound healing assay and Transwell assay were performed to evaluate the transversal and longitudinal migration and invasion abilities of the cells.

OBJECTIVE

SNHG3 was over-expressed in cervical cancer tissues and SiHa cells. In SiHa cells, knocking down SNHG3 significantly inhibited the proliferation (P < 0.001), migration (P < 0.01) and invasion abilities (P < 0.001) of the cells, down-regulated the expression levels of N-cadherin, Snail and vimentin (P < 0.001) and up-regulated the expression of E-cadherin (P < 0.001).

OBJECTIVE

SNHG3 may promote the proliferation, migration and invasion of SiHa cells by activating the EMT signaling pathway.

A review of high-resolution microscopic ghost imaging with a low-dose pseudothermal light

High-resolution imaging is an important issue in various fields of scientific researches and engineering applications. Pseudothermal ghost imaging is one of the subfields of quantum imaging, providing new capabilities beyond conventional imaging methods. Also, it can provide a new viewpoint of imaging physical mechanisms. In this review, we explain the major ideas of pseudothermal ghost imaging, restricting the very important case of high-resolution imaging. We analyse the strategies which can significantly improve the image quality in pseudothermal ghost imaging. It may apply for merging it with common optical imaging methods in the extreme ultraviolet (XUV) or X-ray spectral regime for driving the applications to a wider audience in bioscience and nano-physics.

TDP-43 maintains chondrocyte homeostasis and alleviates cartilage degradation in osteoarthritis

OBJECTIVE

Osteoarthritis (OA) is the most prevalent age-related disorder due to cartilage degradation. Previous studies have identified aberrant chondrocyte homeostasis under extracellular stress as a key pathological mechanism behind cartilage degradation in OA. TDP-43, a DNA/RNA-binding protein has been demonstrated to participate in processing many extracellular stress responses; however, understanding of the role of TDP-43 in OA is limited. This study aims to investigate the role of TDP-43 in chondrocyte homeostasis and cartilage degradation in OA.

METHODS

The role of TDP-43 during degradation of cartilage is examined by experimental posttraumatic OA animal models and human cartilage specimens. Cartilage degradation is assessed by histological analysis, qPCR, and Western blot. The molecular mechanisms are investigated in vitro using human primary chondrocytes.

RESULTS

TDP-43 decreases significantly in degenerated cartilage. TDP-43 concentration is positively correlated with IL-1β concentration in synovial fluid derived from OA patients (Pearson r = 0.95, CI (95%) [0.80, 0.99], P < 0.0001). Intra-articular injection of recombinant TDP-43 significantly alleviates cartilage degradation and subchondral bone remodeling in vivo. In vitro mechanistic analyses show that TDP-43 maintains chondrocyte homeostasis under oxidative stress through regulating stress granule dynamics via G3BP1.

CONCLUSION

The present study indicates that TDP-43 maintains chondrocyte homeostasis under oxidative stress and alleviates cartilage degeneration in osteoarthritis, identifying TDP-43 as a potential target for the diagnosis and treatment of knee OA.

Fizeau drag in graphene plasmonics

Dragging of light by moving media was predicted by Fresnel¹ and verified by Fizeau's celebrated experiments² with flowing water. This momentous discovery is among the experimental cornerstones of Einstein's special relativity theory and is well understood^3,4 in the context of relativistic kinematics. By contrast, experiments on dragging photons by an electron flow in solids are riddled with inconsistencies and have so far eluded agreement with the theory^5-7. Here we report on the electron flow dragging surface plasmon polaritons^8,9 (SPPs): hybrid quasiparticles of infrared photons and electrons in graphene. The drag is visualized directly through infrared nano-imaging of propagating plasmonic waves in the presence of a high-density current. The polaritons in graphene shorten their wavelength when propagating against the drifting carriers. Unlike the Fizeau effect for light, the SPP drag by electrical currents defies explanation by simple kinematics and is linked to the nonlinear electrodynamics of Dirac electrons in graphene. The observed plasmonic Fizeau drag enables breaking of time-reversal symmetry and reciprocity¹⁰ at infrared frequencies without resorting to magnetic fields^11,12 or chiral optical pumping^13,14. The Fizeau drag also provides a tool with which to study interactions and nonequilibrium effects in electron liquids.

POS0647 EFFICACY, SAFETY AND CHARACTERISTICS OF IGURATIMOD-BASED THERAPY IN THE TREATMENT OF UA, ERA AND RA PATIENTS FOR 24 WEEKS: A PROSPECTIVE COHORT STUDY

Background:

Experts emphasize early diagnosis and treatment in RA, but the widely used diagnostic criterias fail to meet the accurate judgment of early rheumatoid arthritis. In 2012, Professor Zhanguo Li took the lead in establishing ERA “Chinese standard”, and its sensitivity and accuracy have been recognized by peers. However, the optimal first-line treatment of patients (pts) with undifferentiated arthritis (UA), early rheumatoid arthritis (ERA), and rheumatoid arthritis (RA) are yet to be established.

Objectives:

To evaluate the efficacy and safety of Iguratimod-based (IGU-based) Strategy in the above three types of pts, and to explore the characteristics of the effects of IGU monotherapy and combined treatment.

Methods:

This prospective cohort study (ClinicalTrials.gov Identifier NCT01548001) was conducted in China. In this phase 4 study pts with RA (ACR 1987 criteria[1]), ERA (not match ACR 1987 criteria[1] but match ACR/EULAR 2010 criteria[2] or 2014 ERA criteria[3]), UA (not match classification criteria for ERA and RA but imaging suggests synovitis) were recruited. We applied different treatments according to the patient’s disease activity at baseline, including IGU monotherapy and combination therapies with methotrexate, hydroxychloroquine, and prednisone. Specifically, pts with LDA and fewer poor prognostic factors were entered the IGU monotherapy group (25 mg bid), and pts with high disease activity were assigned to combination groups. A Chi-square test was applied for comparison. The primary outcomes were the proportion of pts in remission (REM)or low disease activity (LDA) that is DAS28-ESR<2.6 or 3.2 at 24 weeks, as well as the proportion of pts, achieved ACR20, Boolean remission, and good or moderate EULAR response (G+M).

Results:

A total of 313 pts (26 pts with UA, 59 pts with ERA, and 228 pts with RA) were included in this study. Of these, 227/313 (72.5%) pts completed the 24-week follow-up. The results showed that 115/227 (50.7%), 174/227 (76.7%), 77/227 (33.9%), 179/227 (78.9%) pts achieved DAS28-ESR defined REM and LDA, ACR20, Boolean remission, G+M response, respectively. All parameters continued to decrease in all pts after treatment (Fig 1).

Compared with baseline, the three highest decline indexes of disease activity at week 24 were SW28, CDAI, and T28, with an average decline rate of 73.8%, 61.4%, 58.7%, respectively. Results were similar in three cohorts.

We performed a stratified analysis of which IGU treatment should be used in different cohorts. The study found that the proportion of pts with UA and ERA who used IGU monotherapy were significantly higher than those in the RA cohort. While the proportion of triple and quadruple combined use of IGU in RA pts was significantly higher than that of ERA and UA at baseline and whole-course (Fig 2).

A total of 81/313 (25.8%) pts in this study had adverse events (AE) with no serious adverse events. The main adverse events were infection(25/313, 7.99%), gastrointestinal disorders(13/313, 4.15%), liver dysfunction(12/313, 3.83%) which were lower than 259/2666 (9.71%) in the previous Japanese phase IV study[4].

The most common reasons of lost follow-up were: 1) discontinued after remission 25/86 (29.1%); 2) lost 22/86 (25.6%); 3) drug ineffective 19/86 (22.1%).

Conclusion:

Both IGU-based monotherapy and combined therapies are tolerant and effective for treating UA, ERA, and RA, while the decline in joint symptoms was most significant. Overall, IGU combination treatments were most used in RA pts, while monotherapy was predominant in ERA and UA pts.

References:

[1]Levin RW, et al. Scand J Rheumatol 1996, 25(5):277-281.

[2]Kay J, et al. Rheumatology 2012, 51(Suppl 6):vi5-9.

[3]Zhao J, et al. Clin Exp Rheumatol 2014, 32(5):667-673.

[4]Mimori T, et al. Mod Rheumatol 2019, 29(2):314-323.

Disclosure of Interests:

None declared

A wide-ranging Pseudomonas aeruginosa PeptideAtlas build: A useful proteomic resource for a versatile pathogen

Pseudomonas aeruginosa is an important opportunistic human pathogen with high prevalence in nosocomial infections. This microorganism is a good model for understanding biological processes such as the quorum-sensing response, the metabolic integration of virulence, the mechanisms of global regulation of bacterial physiology, and the evolution of antibiotic resistance. Till now, P. aeruginosa proteomic data, although available in several on-line repositories, were dispersed and difficult to access. In the present work, proteomes of the PAO1 strain grown under different conditions and from diverse cellular compartments have been joined to build the Pseudomonas PeptideAtlas. This resource is a comprehensive mass spectrometry-derived peptide and inferred protein database with 71.3% coverage of the total predicted proteome of P. aeruginosa PAO1, the highest coverage among bacterial PeptideAtlas datasets. The proteins included cover 89% of metabolic proteins, 72% of proteins involved in genetic information processing, 83% of proteins responsible for environmental information processing, more than 88% of the ones related to quorum sensing and biofilm formation, and 89% of proteins responsible for antimicrobial resistance. It exemplifies a necessary tool for targeted proteomics studies, system-wide observations, and cross-species observational studies. The manuscript describes the building of the PeptideAtlas and the contribution of the different proteomic data used. SIGNIFICANCE: Pseudomonas aeruginosa is among the most versatile human bacterial pathogens. Studies of its proteome are very important as they can reveal virulence factors and mechanisms of antibiotic resistance. The construction of a proteomic resource such as the PeptideAtlas enables targeted proteomics studies, system-wide observations, and cross-species observational studies.

Molecular Analysis of the Kidney From a Patient With COVID-19-Associated Collapsing Glomerulopathy

Recent case reports suggest that coronavirus disease 2019 (COVID-19) is associated with collapsing glomerulopathy in African Americans with apolipoprotein L1 gene (APOL1) risk alleles; however, it is unclear whether disease pathogenesis is similar to HIV-associated nephropathy. RNA sequencing analysis of a kidney biopsy specimen from a patient with COVID-19–associated collapsing glomerulopathy and APOL1 risk alleles (G1/G1) revealed similar levels of APOL1 and angiotensin-converting enzyme 2 (ACE2) messenger RNA transcripts as compared with 12 control kidney samples downloaded from the GTEx (Genotype-Tissue Expression) Portal. Whole-genome sequencing of the COVID-19–associated collapsing glomerulopathy kidney sample identified 4 indel gene variants, 3 of which are of unknown significance with respect to chronic kidney disease and/or focal segmental glomerulosclerosis. Molecular profiling of the kidney demonstrated activation of COVID-19–associated cell injury pathways such as inflammation and coagulation. Evidence for direct severe acute respiratory syndrome coronavirus 2 infection of kidney cells was lacking, which is consistent with the findings of several recent studies. Interestingly, immunostaining of kidney biopsy sections revealed increased expression of phospho-STAT3 (signal transducer and activator of transcription 3) in both COVID-19–associated collapsing glomerulopathy and HIV-associated nephropathy as compared with control kidney tissue. Importantly, interleukin 6–induced activation of STAT3 may be a targetable mechanism driving COVID-19–associated acute kidney injury.

The STING-IRF3 pathway is involved in lipotoxic injury of pancreatic β cells in type 2 diabetes

Lipotoxic injury of pancreatic β cells is an important pathological feature in type 2 diabetes mellitus (T2DM). Stimulator of interferon genes (STING) can recognize its own DNA leaked into the cytoplasm from damaged mitochondria or nuclei of the host cell, thus activating its downstream factor interferon regulatory factor 3 (IRF3), causing inflammation and apoptosis. The STING-IRF3 signaling pathway is closely related to glycolipid metabolism, but its relationship with the lipotoxicity of pancreatic β cells has rarely been reported. Here, we investigated the role of the STING-IRF3 signaling pathway in lipotoxicity-induced inflammation, apoptosis, and dysfunction of pancreatic β cells. We examined the activation of STING and IRF3 in islets of db/db mice and identified the role of the STING-IRF3 signaling pathway in palmitic acid (PA)-induced lipotoxic injury of INS-1, a rat insulinoma cell line. STING and phosphorylated IRF3 including downstream interferon-β were upregulated in islets of db/db mice and PA-induced INS-1 cells. Gene silencing of STING or IRF3 ameliorated PA-induced INS-1 cell inflammation and apoptosis, and reversed impaired insulin synthesis. Additionally, PA induced downregulation of the phosphoinositide 3-kinase-AKT signaling pathway, and impaired high glucose-stimulated insulin secretion was reversed after knockdown of STING or IRF3. Our results suggest that activation of the STING-IRF3 pathway triggers inflammation and apoptosis of pancreatic β cells, leading to β-cell damage and dysfunction. Hence, inhibition of this signaling pathway may represent a novel approach for β-cell protection in T2DM.

Automated Measurements of Key Morphological Features of Human Embryos for IVF

A major challenge in clinical In-Vitro Fertilization (IVF) is selecting the highest quality embryo to transfer to the patient in the hopes of achieving a pregnancy. Time-lapse microscopy provides clinicians with a wealth of information for selecting embryos. However, the resulting movies of embryos are currently analyzed manually, which is time consuming and subjective. Here, we automate feature extraction of time-lapse microscopy of human embryos with a machine-learning pipeline of five convolutional neural networks (CNNs). Our pipeline consists of (1) semantic segmentation of the regions of the embryo, (2) regression predictions of fragment severity, (3) classification of the developmental stage, and object instance segmentation of (4) cells and (5) pronuclei. Our approach greatly speeds up the measurement of quantitative, biologically relevant features that may aid in embryo selection.

Clinical and immunologic features among COVID-19-affected mother-infant pairs: antibodies to SARS-CoV-2 detected in breast milk

The coronavirus disease 2019 (COVID-19) pandemic remains threatening to women and children, but clinical evidence regarding women during pregnancy, puerperium and lactation is limited. We assessed clinical and immunologic features of and breastfeeding advice provided to mother–infant pairs. This observational analysis was conducted in a tertiary-care centre in Wuhan, China. Pregnant patients with laboratory-confirmed COVID-19 who delivered during hospitalization were enrolled. Clinical characteristics and serial specimens of the mother–infant pairs were examined, supplemented with follow-ups regarding recovery and breastfeeding. Fourteen pregnant patients had live births and recovered well; four patients continued breastfeeding while taking precautions. No neonatal infections were observed. No infants developed COVID-19 during breastfeeding. Common maternal symptoms were fever (11/14, 78.1%) and cough (6/14, 42.9%). A pregnancy-specific symptom was abnormal foetal movement, which was noticed by three patients (21.4%). The mean virus shedding time was 9 days (standard deviation, 6 days; range, 1–22 days). The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome was not detected in breast milk or maternal vaginal secretions. Immunologic assay revealed seroconversion of IgM on day 8 after onset and IgG on day 28. Both IgM and IgG antibodies to SARS-CoV-2 were detected in breast milk, cord blood and neonatal serum. The study results suggest that passive acquisition of antibodies against SARS-CoV-2 is available by ingesting breast milk. Breastfeeding has a low risk of transmitting SARS-CoV-2 or escalating maternal disease, so continuing breastfeeding with prudent precautions is encouraged.