Wunderlich syndrome as a rare complication of polyarteritis nodosa: a case report

Spontaneous subcapsular and perirenal hemorrhage, known as Wunderlich syndrome (WS), is a rare clinical manifestation of polyarteritis nodosa (PAN). We report a case of a 48-year-old male with a history of recurrent episodes of leg muscle tenderness and dysesthesia, bilateral flank pain, painful nodular skin lesions in the lower limbs, weight loss, and difficult-to-control arterial hypertension. The abdominopelvic computed tomography angiography showed a large left perirenal hematoma, leading to the patient's admission to the intensive care unit. After the exclusion of infectious or neoplastic foci, the patient was diagnosed with PAN and started intravenous methylprednisolone pulses with a good response. Since WS is a rare initial clinical manifestation of PAN, an early diagnosis and aggressive treatment will significantly improve clinical outcomes.

Cell specification and functional interactions in the pig blastocyst inferred from single-cell transcriptomics and uterine fluids proteomics

The embryonic development of the pig comprises a long in utero pre- and peri-implantation development, which dramatically differs from mice and humans. During this peri-implantation period, a complex series of paracrine signals establishes an intimate dialogue between the embryo and the uterus. To better understand the biology of the pig blastocyst during this period, we generated a large dataset of single-cell RNAseq from early and hatched blastocysts, spheroid and ovoid conceptus and proteomic datasets from corresponding uterine fluids. Our results confirm the molecular specificity and functionality of the three main cell populations. We also discovered two previously unknown subpopulations of the trophectoderm, one characterised by the expression of LRP2, which could represent progenitor cells, and the other, expressing pro-apoptotic markers, which could correspond to the Rauber's layer. Our work provides new insights into the biology of these populations, their reciprocal functional interactions, and the molecular dialogue with the maternal uterine environment.

Single-cell RNA sequencing identifies senescence as therapeutic target in rhabdomyolysis-induced acute kidney injury

BACKGROUND

The role of macrophages in the development of rhabdomyolysis-induced acute kidney injury (RM-AKI) has been established, but an in-depth understanding of the changes in the immune landscape could help to improve targeted strategies. Whereas senescence is usually associated with chronic kidney processes, we also wished to explore whether senescence could also occur in AKI and whether senolytics could act on immune cells.

METHODS

Single-cell RNA sequencing was used in the murine glycerol-induced RM-AKI model to dissect the transcriptomic characteristics of CD45+ live cells sorted from kidneys 2 days after injury. Public datasets from murine AKI models were reanalysed to explore cellular senescence signature in tubular epithelial cells (TECs). A combination of senolytics (dasatinib and quercetin, DQ) was administered to mice exposed or not to RM-AKI.

RESULTS

Unsupervised clustering of nearly 17 000 single-cell transcriptomes identified seven known immune cell clusters. Sub-clustering of the mononuclear phagocyte cells revealed nine distinct cell sub-populations differently modified with RM. One macrophage cluster was particularly interesting since it behaved as a critical node in a trajectory connecting one major histocompatibility complex class IIhigh (MHCIIhigh) cluster only present in Control to two MHCIIlow clusters only present in RM-AKI. This critical cluster expressed a senescence gene signature, that was very different from that of the TECs. Senolytic DQ treatment blocked the switch from a F4/80highCD11blow to F4/80lowCD11bhigh phenotype, which correlated with prolonged nephroprotection in RM-AKI.

CONCLUSIONS

Single-cell RNA sequencing unmasked novel transitional macrophage subpopulation associated with RM-AKI characterized by the activation of cellular senescence processes. This work provides a proof-of-concept that senolytics nephroprotective effects may rely, at least in part, on subtle immune modulation.

Modulation of the functional interfaces between retroviral intasomes and the human nucleosome

Infection by retroviruses as HIV-1 requires the stable integration of their genome into the host cells. This process needs the formation of integrase (IN)-viral DNA complexes, called intasomes, and their interaction with the target DNA wrapped around nucleosomes within cell chromatin. To provide new tools to analyze this association and select drugs, we applied the AlphaLISA technology to the complex formed between the prototype foamy virus (PFV) intasome and nucleosome reconstituted on 601 Widom sequence. This system allowed us to monitor the association between both partners and select small molecules that could modulate the intasome/nucleosome association. Using this approach, drugs acting either on the DNA topology within the nucleosome or on the IN/histone tail interactions have been selected. Within these compounds, doxorubicin and histone binders calixarenes were characterized using biochemical, in silico molecular simulations and cellular approaches. These drugs were shown to inhibit both PFV and HIV-1 integration in vitro. Treatment of HIV-1-infected PBMCs with the selected molecules induces a decrease in viral infectivity and blocks the integration process. Thus, in addition to providing new information about intasome-nucleosome interaction determinants, our work also paves the way for further unedited antiviral strategies that target the final step of intasome/chromatin anchoring. IMPORTANCE In this work, we report the first monitoring of retroviral intasome/nucleosome interaction by AlphaLISA. This is the first description of the AlphaLISA application for large nucleoprotein complexes (>200 kDa) proving that this technology is suitable for molecular characterization and bimolecular inhibitor screening assays using such large complexes. Using this system, we have identified new drugs disrupting or preventing the intasome/nucleosome complex and inhibiting HIV-1 integration both in vitro and in infected cells. This first monitoring of the retroviral/intasome complex should allow the development of multiple applications including the analyses of the influence of cellular partners, the study of additional retroviral intasomes, and the determination of specific interfaces. Our work also provides the technical bases for the screening of larger libraries of drugs targeting specifically these functional nucleoprotein complexes, or additional nucleosome-partner complexes, as well as for their characterization.

Impact de l’infection par le SARS-CoV-2 sur l’activité de la maladie des patients atteints de rhumatisme psoriasique sous bDMARD : données réelles

Introduction

L’infection par le SARS-CoV-2 peut entraîner une inflammation sévère et il a été suggéré d’induire des poussées de rhumatisme psoriasique (RP). Cependant, l’impact sur l’activité de la maladie et la réponse aux DMARD biologiques modificateurs de la maladie (bDMARD) reste inconnu.

Patients et méthodes

Nous avons réalisé une analyse rétrospective incluant tous les patients atteints de RP, répondant aux critères CASPAR et sous biothérapie, suivis dans le service de rhumatologie d’un CHU universitaire tertiaire. Les données démographiques et cliniques, y compris la survenue d’une infection par le SARS-CoV-2, ont été collectées à partir de notre base de données nationale (reuma.pt). L’activité de la maladie (CDAI, SDAI, DAS28 4v, BASDAI, ASDAS) et les réponses aux bDMARD (réponses EULAR, ASDAS, ASAS, ACR et PsARC) ont été évaluées avant et après l’infection par le SARS-Cov-2.

Résultats

Au total, 102 patients atteints de RP ont été inclus. Cinquante-deux étaient des femmes (51 %). L’âge moyen était de 53 ± 11,09 ans et la durée médiane de la maladie était de 15 ans [min 2, max 47]. Au total, 54 (53 %) patients avaient une atteinte axiale prédominante, 26 (26 %) périphérique et 36 (37 %) enthésopathique. Le bDMARD le plus utilisé était l’étanercept (n = 28, 27,5 %) suivi de l’adalimumab (n = 22, 21,6 %) et du sécukinumab (n = 18, 17,6 %). La prévalence de l’infection par le SARS-CoV-2 était de 15,7 % (n = 16). Soixante-trois pour cent ont reçu le vaccin BNT162b2 (Pfizer/BioNtech), 31 % ont reçu l’ARNm-1273 (Moderna), 13 % ont reçu l’AZD1222 (AstraZeneca) et 13 % ont reçu l’AD26.COV2.S (Janssen/Johnson & Johnson). Soixante-trois pour cent étaient infectés avant toute vaccination, 13 % après la première dose et 25 % après la seconde. Les symptômes les plus fréquents étaient l’anosmie (65 %), la dysgueusie (56 %) et la toux (56 %). Tous les patients se sont complètement remis de l’infection, sans nécessiter d’hospitalisation. Quel que soit le score utilisé, la différence entre l’activité moyenne de la maladie après l’infection par le SARS-CoV-2 et celle au départ n’a pas atteint la signification statistique. Au départ et après l’infection, les paramètres moyens de l’activité de la maladie étaient respectivement : CDAI 8,6 ± 5,7 vs 8,6 ± 5,7, p = 0,997 ; SDAI 9,3 ± 6,6 contre 9,2 ± 6,1, p = 0,928 ; DAS 28 4v 2,9 ± 1,2 contre 2,9 ± 1,2, p = 0,818 ; BASDAI 3,6 ± 2,6 contre 3,2 ± 2,7, p = 0,506 ; ASDAS 2,2 ± 1,2 contre 2,2 ± 1, p = 0,721. Le nombre de patients ne répondant pas aux bDMARD (selon EULAR, ASDAS, ASAS, ACR et PsARC) avant l’infection n’était pas différent de celui post-infection.

Conclusion

Notre étude suggère que l’infection par le SARS-CoV-2 n’a aucun impact négatif sur l’activité de la maladie PSA et les réponses bDMARD. Cependant, d’autres études sont encore nécessaires pour mieux comprendre les effets à long terme de l’infection par le SARS-CoV-2.

Developing and validating high-value patient digital follow-up services: a pilot study in cardiac surgery

Background

The existing digital healthcare solutions demand a service development approach that assesses needs, experience, and outcomes, to develop high-value digital healthcare services. The objective of this study was to develop a digital transformation of the patients’ follow-up service after cardiac surgery, based on a remote patient monitoring service that would respond to the real context challenges.

Methods

The study followed the Design Science Research methodology framework and incorporated concepts from the Lean startup method to start designing a minimal viable product (MVP) from the available resources. The service was implemented in a pilot study with 29 patients in 4 iterative develop-test-learn cycles, with the engagement of developers, researchers, clinical teams, and patients.

Results

Patients reported outcomes daily for 30 days after surgery through Internet-of-Things (IoT) devices and a mobile app. The service’s evaluation considered experience, feasibility, and effectiveness. It generated high satisfaction and high adherence among users, fewer readmissions, with an average of 7 ± 4.5 clinical actions per patient, primarily due to abnormal systolic blood pressure or wound-related issues.

Conclusions

We propose a 6-step methodology to design and validate a high-value digital health care service based on collaborative learning, real-time development, iterative testing, and value assessment.

MO278: Immunolandscaping of Rhabdomyolysis-Induced Acute Kidney Injury

BACKGROUND AND AIMS

Acute kidney injury (AKI) accounts for 13.3 million cases per year worldwide and further responsible for 1.7 million deaths per year [1]. Increasing incidence of AKI, progression toward CKD or end-stage renal disease (ESRD), affect on long term health, high mortality, morbidity and high costs are all accountable for the need to analyze AKI at a closer level [2].

Rhabdomyolysis (RM) accounting for 10% of AKI cases is due to damage of the skeletal muscle causing a release of muscle cell contents like myoglobin and toxins into the bloodstream leading to AKI, renal failure and possibly death. RM-induced AKI (RIAKI) occurs due to a variety of causes like fall risk, exposure to drugs, infections, muscle hypoxia, infections, body-temperature changes and metabolic and electrolyte disorders [3].

The immune system has been reported to play a role in the pathogenesis of AKI through inflammatory pathways. Macrophages are known to be involved in AKI to CKD transition [4]. Macrophages play an important role in the pathogenesis of RIAKI. While macrophage subtypes (inflammatory type) have been reported to drive RIAKI lesions and prognosis [5], the role of the other immune cells needs to be explored.

The aim of this study was to analyze the recruitment of the whole immune system during RIAKI through single-cell RNA sequencing.

METHOD

Two month old C57BL/6J male mice were used for this study. Mice were administered saline (control) or glycerol i.m (7.5 mL/kg 50% glycerol diluted in saline) for induction of RM. Mouse tail vein blood was collected at 6, 24 and 48 h and serum was obtained after centrifugation (5 min at 2000 rpm). Biochemical analysis tests were used to evaluate RM intensity (creatinine phosphokinase, CPK) and renal function (blood urea nitrogen, BUN) using a Pentra 400 analyzer.

To analyze the immune cell recruitment in kidney, kidneys from control and glycerol treated mice were decapsulated, minced and incubated with collagenase and DNase. The dissociated cells were then incubated in red cell lysis buffer and passed through a 40 µm filter. The dissociated cells were further incubated with CD45 antibodies and a viability marker. Kidney CD45 live cells were sorted using BD Influx cell sorter. Preparation of single cell libraries was done and single-cell RNA sequencing was performed according to 10× Genomics protocol.

RESULTS

Eight clusters (macrophages, monocytes, endothelial cells, neutrophils, natural killer T cells, B cells, T cells and dendritic cells) were revealed after single-cell RNA sequencing of CD45+ renal cells. Recruitment of macrophages, monocytes and neutrophils were revealed to be modified by RIAKI. As expected, NF-kB signaling pathway was the major pathway upregulated in multiple clusters. Pathway analysis in T cell cluster showcased T cell selection and differentiation and T cell receptor signaling pathway. AA467197 (a long non-coding RNA which has been reported in renal ischemia–reperfusion) was upregulated through differential expression analysis in multiple clusters. Macrophage subclustering revealed a high macrophage diversity in the seven macrophage subclusters that shared markers for macrophage subtypes (M1, M2) and pro-inflammatory markers. KLf9 was upregulated in cluster 7, which has been reported to be a stress-responsive gene associated having pro-inflammatory effect. NF-kB and IL-2 STAT5 signaling pathways were the major pathways upregulated in multiple clusters. Drug repositioning studies with connectivity map showcased SRC inhibitions as potent pharmacological intervention strategy.

CONCLUSION

This study revealed the immune landscaping and pathways associated in RIAKI. Single-cell approach illustrated macrophages diversity in pathological context and suggested candidates for further therapeutic approaches.

Nuclear HMGB1 protects from nonalcoholic fatty liver disease through negative regulation of liver X receptor

Dysregulations of lipid metabolism in the liver may trigger steatosis progression, leading to potentially severe clinical consequences such as nonalcoholic fatty liver diseases (NAFLDs). Molecular mechanisms underlying liver lipogenesis are very complex and fine-tuned by chromatin dynamics and multiple key transcription factors. Here, we demonstrate that the nuclear factor HMGB1 acts as a strong repressor of liver lipogenesis. Mice with liver-specific Hmgb1 deficiency display exacerbated liver steatosis, while Hmgb1-overexpressing mice exhibited a protection from fatty liver progression when subjected to nutritional stress. Global transcriptome and functional analysis revealed that the deletion of Hmgb1 gene enhances LXRα and PPARγ activity. HMGB1 repression is not mediated through nucleosome landscape reorganization but rather via a preferential DNA occupation in a region carrying genes regulated by LXRα and PPARγ. Together, these findings suggest that hepatocellular HMGB1 protects from liver steatosis development. HMGB1 may constitute a new attractive option to therapeutically target the LXRα-PPARγ axis during NAFLD.

Tumor-associated high endothelial venules mediate lymphocyte entry into tumors and predict response to PD-1 plus CTLA-4 combination immunotherapy

Recruitment of lymphocytes into tumors is critical for anti-tumor immunity and efficacious immunotherapy. We show in murine models that tumor-associated high endothelial venules (TA-HEVs) are major sites of lymphocyte entry into tumors at baseline and upon treatment with anti-PD-1/anti-CTLA-4 immune checkpoint blockade (ICB). TA-HEV endothelial cells (TA-HECs) derive from post-capillary venules, co-express MECA-79⁺ HEV sialomucins and E/P-selectins, and are associated with homing and infiltration into tumors of various T cell subsets. Intravital microscopy further shows that TA-HEVs are the main sites of lymphocyte arrest and extravasation into ICB-treated tumors. Increasing TA-HEC frequency and maturation increases the proportion of tumor-infiltrating stem-like CD8⁺ T cells, and ameliorates ICB efficacy. Analysis of tumor biopsies from 93 patients with metastatic melanoma reveals that TA-HEVs are predictive of better response and survival upon treatment with anti-PD-1/anti-CTLA-4 combination. These studies provide critical insights into the mechanisms governing lymphocyte trafficking in cancer immunity and immunotherapy.

Identification of Loci Enabling Stable and High-Level Heterologous Gene Expression

Efficient and reliable genome engineering technologies have yet to be developed for diatoms. The delivery of DNA in diatoms results in the random integration of multiple copies, quite often leading to heterogeneous gene activity, as well as host instability. Transgenic diatoms are generally selected on the basis of transgene expression or high enzyme activity, without consideration of the copy number or the integration locus. Here, we propose an integrated pipeline for the diatom, Phaeodactylum tricornutum, that accurately quantifies transgene activity using a β-glucuronidase assay and the number of transgene copies integrated into the genome through Droplet Digital PCR (ddPCR). An exhaustive and systematic analysis performed on 93 strains indicated that 42% of them exhibited high β-glucuronidase activity. Though most were attributed to high transgene copy numbers, we succeeded in isolating single-copy clones, as well as sequencing the integration loci. In addition to demonstrating the impact of the genomic integration site on gene activity, this study identifies integration sites for stable transgene expression in Phaeodactylum tricornutum.

Can biochemical endpoints improve the sensitivity of the biomonitoring strategy using bioassays with standard species, for water quality evaluation?

The Water Framework Directive (WFD) was adopted in 2000 and is a common framework for water policy, management and protection in Europe. The WFD assesses specific parameters; however, it ignores indicators of ecosystem functioning and sub-individual performance. Reservoirs are strongly influenced by anthropogenic activities that promote their imbalance. Bioassays and biomarkers are useful tools to link the chemical, ecological and toxicological assessments in water quality assessments. These approaches can be complementary to WFD methodologies, allowing the detection of impacts on the ecosystem. This study evaluated if the biochemical parameters can improve the sensitivity of the biomonitoring strategy using bioassays with the standard species Daphnia magna, in the assessment of the ecological quality of water reservoirs. To this end, water samples of Portuguese reservoirs were analysed in three sampling periods (Autumn 2018 and Spring, Autumn 2019). In parallel, a physicochemical characterization of waters was performed. D. magna feeding rate assays were performed for 24 h. After exposure, metabolism, oxidative stress and lipid peroxidation biomarkers were evaluated. Feeding rate assays showed sensitivity to different reservoirs. Biomarkers showed a higher sensitivity and can therefore improve the sensitivity of the biomonitoring strategy using bioassays. Bioassays and biomarkers approach allowed to highlight potential sources of stress, more related to the quality of the seston than to chemical contamination. This work highlights the complementarity between bioassays and biomarkers to identify ecotoxicological effects of surface waters, and can be extremely useful, especially in cases where the biotic indices are difficult to establish, such as reservoirs.

Comparative clinical prognosis of massive and non-massive pulmonary embolism: A registry-based cohort study

AIMS

Little is known about the prognosis of patients with massive pulmonary embolism (PE) and its risk of recurrent venous thromboembolism (VTE) compared with non-massive PE, which may inform clinical decisions. Our aim was to compare the risk of recurrent VTE, bleeding, and mortality after massive and non-massive PE during anticoagulation and after its discontinuation.

METHODS AND RESULTS

We included all participants in the RIETE registry who suffered a symptomatic, objectively confirmed segmental or more central PE. Massive PE was defined by a systolic hypotension at clinical presentation (<90 mm Hg). We compared the risks of recurrent VTE, major bleeding, and mortality using time-to-event multivariable competing risk modeling. There were 3.5% of massive PE among 38 996 patients with PE. During the anticoagulation period, massive PE was associated with a greater risk of major bleeding (subhazard ratio [sHR] 1.72, 95% confidence interval [CI] 1.28-2.32), but not of recurrent VTE (sHR 1.15, 95% CI 0.75-1.74) than non-massive PE. An increased risk of mortality was only observed in the first month after PE. After discontinuation of anticoagulation, among 11 579 patients, massive PE and non-massive PE had similar risks of mortality, bleeding, and recurrent VTE (sHR 0.85, 95% CI 0.51-1.40), but with different case fatality of recurrent PE (11.1% versus 2.4%, P = .03) and possibly different risk of recurrent fatal PE (sHR 3.65, 95% CI 0.82-16.24).

CONCLUSION

In this large prospective registry, the baseline hemodynamic status of the incident PE did not influence the risk of recurrent VTE, during and after the anticoagulation periods, but was possibly associated with recurrent PE of greater severity.

P229 Primary cardiac angiosarcoma of the right atrium: a rare entity presenting with an atrial arrhythmia

Introduction

Primary cardiac tumors are rare entities and 75% are benign. Angiosarcoma is the most common malignant primary cardiac tumor.

We report the case of cardiac angiosarcoma presenting with an atrial arrhythmia.

Clinical case

A 39-year-old female patient with no past medical history presented to the emergency department with heart palpitations and atypical chest pain.

Electrocardiogram on admission showed atrial flutter with a heart rate of 153 beats per minute.

Laboratory analysis were performed showing elevated D-dimer levels (2210 ug/L).

A thoracic CT scan was performed, which ruled out pulmonary embolism, but showed multiple pulmonary nodules and a right atrial (RA) mass measuring 48 mm that could correspond to a thrombus or neoplasia.

The patient was admitted in the Cardiology ICU of our hospital and was started on beta-blocker and amiodarone with conversion to sinus rhythm. Additional exams were performed:

- Transthoracic echocardiogram (TTE) revealed an heterogenous 32,6 x 17,7 mm mass in the lateral wall of the RA with an adherent mobile mass near the tricuspid valve with 28 mm diameter (possible adherent thrombus).

- Cardiac magnetic resonance imaging confirmed a RA tumor with invasion of the atrial free wall and compression of the superior vena cava.

Due to the unclear etiology of the RA mass, ultrasound-guided intracardiac biopsy was performed. Pathological examination revealed spindle cell proliferation, consistent with the diagnosis of angiosarcoma. Immunohistochemical staining was positive for Vimentin, CD34 and CD31, with 70% Ki67 expression.

Later on, the patient developed melena with significant drop of hemoglobin levels, requiring daily red blood cell transfusions and anticoagulation had to be stopped.

The patient was transferred to the Internal Medicine ward and thoracic-abdomen-pelvis staging computed tomography (CT) scan showed a significant increase in the number of pulmonary nodules, bilateral ovarian masses, 4 hepatic nodules and ileum metastization.

During hospitalization, the patient developed right leg deep venous thrombosis and thoracic CT scan revealed bilateral pulmonary embolism.

After improvement of the clinical status, palliative chemotherapy was started and the patient was discharged, maintaining regular outpatient follow-up in the Oncology Department for 1 month.

Cardiac angiosarcoma generally presents in a late stage of the disease with metastatic involvement. When surgical treatment is not possible, despite agressive chemotherapy, the prognosis remains poor.

Abstract P229 Figure. Echocardiogram: right atrium mass

Animal Models to Study Cancer and Its Microenvironment

Cancers are complex tissues composed by genetically altered cancer cells and stromal elements such as inflammatory/immune cells, fibroblasts, endothelial cells and pericytes, neuronal cells, and a non-cellular component, the extracellular matrix. The complex network of interactions and crosstalk established between cancer cells and the supportig cellular and non-cellular components of the microenvironment are of extreme importance for tumor initiation and progression, strongly impacting the course and the outcome of the disease. Therefore, a better understanding of the tumorigenic processes implies the combined study of the cancer cell and the biologic, chemical and mechanic constituents of the tumor microenvironment, as their concerted action plays a major role in the carcinogenic pathway and is a key determinant of the efficacy of anti-cancer treatments. The use of animal models (e.g. Mouse, Zebrafish and Drosophila) to study cancer has greatly impacted our understanding of the processes governing initiation, progression and metastasis and allowed the discovery and pre-clinical validation of novel cancer treatments as it allows to recreate tumor development in a more pathophysiologic environment.

Single-Cell Analysis Reveals Heterogeneity of High Endothelial Venules and Different Regulation of Genes Controlling Lymphocyte Entry to Lymph Nodes

High-endothelial venules (HEVs) are specialized blood vessels allowing recirculation of naive lymphocytes through lymphoid organs. Here, using full-length, single-cell RNA sequencing, RNA fluorescence in situ hybridization (FISH), flow cytometry, and immunohistofluorescence, we reveal the heterogeneity of HEVs in adult mouse peripheral lymph nodes (PLNs) under conditions of homeostasis, antigenic stimulation, and after inhibition of lymphotoxin-β receptor (LTβR) signaling. We demonstrate that HEV endothelial cells are in an activated state during homeostasis, and we identify the genes characteristic of the differentiated HEV phenotype. We show that LTβR signaling regulates many HEV genes and pathways in resting PLNs and that immune stimulation induces a global and temporary inflammatory phenotype in HEVs without compromising their ability to recruit naive lymphocytes. Most importantly, we uncover differences in the regulation of genes controlling lymphocyte trafficking, Glycam1, Fut7, Gcnt1, Chst4, B3gnt3, and Ccl21a, that have implications for HEV function and regulation in health and disease.

Niacin induces miR-502-3p expression which impairs insulin sensitivity in human adipocytes

MicroRNAs have been involved in insulin resistance (IR). As the mechanism whereby niacin, an anti-dyslipidemic agent, leads to IR remains elusive, we sought to identify differentially expressed microRNAs in adipose tissue (AT) of individuals receiving niacin and to explore the link between microRNAs, niacin and IR in human adipocytes.In a double-blind controlled study, 22 obese men received extended-release niacin or placebo over 8 weeks. Bioclinical data and subcutaneous AT biopsies were obtained before and after treatment. AT microRNA expression profiles were determined using RTqPCR for 758 human-specific microRNAs. hMADS adipocytes were treated with niacin, or acipimox (a niacin-like drug without effect on IR), or transfected with miR-502-3p. Glucose uptake and Western blotting were performed.In obese men, insulin sensitivity decreased after niacin treatment. In AT, the expression of 6 microRNAs including miR-502-3p was up-regulated. Treatment of hMADS adipocytes with niacin specifically increased miR-502-3p expression. Acipimox had no effect. Overexpression of miR-502-3p in adipocytes led to reduced insulin-induced glucose uptake and lower insulin-stimulated AKT phosphorylation.Long term niacin treatment altered microRNA expression levels in human AT. Increased miR-502-3p expression may play a role in the mediation of IR due to niacin in adipocytes.The study is registered in Clinical Trials NCT01083329 and EudraCT 2009-012124-85.

Caloric Restriction and Diet-Induced Weight Loss Do Not Induce Browning of Human Subcutaneous White Adipose Tissue in Women and Men with Obesity

Caloric restriction (CR) is standard lifestyle therapy in obesity management. CR-induced weight loss improves the metabolic profile of individuals with obesity. In mice, occurrence of beige fat cells in white fat depots favors a metabolically healthy phenotype, and CR promotes browning of white adipose tissue (WAT). Here, human subcutaneous abdominal WAT samples were analyzed in 289 individuals with obesity following a two-phase dietary intervention consisting of an 8 week very low calorie diet and a 6-month weight-maintenance phase. Before the intervention, we show sex differences and seasonal variation, with higher expression of brown and beige markers in women with obesity and during winter, respectively. The very low calorie diet resulted in decreased browning of subcutaneous abdominal WAT. During the whole dietary intervention, evolution of body fat and insulin resistance was independent of changes in brown and beige fat markers. These data suggest that diet-induced effects on body fat and insulin resistance are independent of subcutaneous abdominal WAT browning in people with obesity.

Muscle transcriptome analysis reveals molecular pathways and biomarkers involved in extreme ultimate pH and meat defect occurrence in chicken

The processing ability and sensory quality of chicken breast meat are highly related to its ultimate pH (pHu), which is mainly determined by the amount of glycogen in the muscle at death. To unravel the molecular mechanisms underlying glycogen and meat pHu variations and to identify predictive biomarkers of these traits, a transcriptome profiling analysis was performed using an Agilent custom chicken 8 × 60 K microarray. The breast muscle gene expression patterns were studied in two chicken lines experimentally selected for high (pHu+) and low (pHu-) pHu values of the breast meat. Across the 1,436 differentially expressed (DE) genes found between the two lines, many were involved in biological processes related to muscle development and remodelling and carbohydrate and energy metabolism. The functional analysis showed an intensive use of carbohydrate metabolism to produce energy in the pHu- line, while alternative catabolic pathways were solicited in the muscle of the pHu+ broilers, compromising their muscle development and integrity. After a validation step on a population of 278 broilers using microfluidic RT-qPCR, 20 genes were identified by partial least squares regression as good predictors of the pHu, opening new perspectives of screening broilers likely to present meat quality defects.

Treatment of long anterior urethral stricture associated to lichen sclerosus

INTRODUCTION

Panurethral stricture associated with lichen sclerosus is a therapeutic challenge. We present the analysis of our results using two urethroplasty techniques based on oral mucosa graft.

MATERIAL AND METHOD

Retrospective study in patients with long anterior urethral stricture (>8cm) associated with lichen sclerosus. Patients received urethroplasty with oral mucosa graft technique according Kulkarni (n=25) or two-step Johanson-Bracka urethroplasty (n=15). Demographics, operative time, complications (Clavien-Dindo), hospital stay, days with catheter, EAV postoperative pain, failure rate, need for retreatment and functional data including IPSS, QoL, Qmax, post void residual (PVR) are evaluated.

RESULTS

In all cases there was involvement of glandular and penile urethra, and in 75% of bulbar urethra. A single graft was used in 22.5%, two in 72.5% and three in 5%. Patients treated at a single step were younger (P=.007). Although the length of the stenosis was equivalent in both techniques (P=.96), relapse and complication rates were higher in two-step surgery (P=.05 and P=.03; respectively) and so was operative time (P<.0001) and overall stay (P=.0002). There were no differences in preoperative IPSS, QoL, Qmax or PVR, neither in postoperative values of IPSS or Qmax; but there was a difference in QoL (P=.006) and PVR (P=.03) favouring single-step urethroplasty. VAS pain on postoperative day 1 was also lower in Kulkarni urethroplasty than in the first step of Johanson-Bracka technique (P<.0001).

CONCLUSIONS

In patients with lichen sclerosus and long anterior urethral stricture Kulkarni urethroplasty provides more efficient and better patient reported outcomes than Johanson-Bracka urethroplasty. It also prevents cosmetic, sexual and voiding temporary deterioration inherent to 2-step surgery.

Circulating miR-155, miR-145 and let-7c as diagnostic biomarkers of the coronary artery disease

Coronary artery disease (CAD) is the most prevalent cause of mortality and morbidity worldwide and the number of individuals at risk is increasing. To better manage cardiovascular diseases, improved tools for risk prediction including the identification of novel accurate biomarkers are needed. MicroRNA (miRNA) are essential post-transcriptional modulators of gene expression leading to mRNA suppression or translational repression. Specific expression profiles of circulating miRNA have emerged as potential noninvasive diagnostic biomarkers of diseases. The aim of this study was to identify the potential diagnostic value of circulating miRNA with CAD. Circulating miR-145, miR-155, miR-92a and let-7c were selected and validated by quantitative PCR in 69 patients with CAD and 30 control subjects from the cross-sectional study GENES. The expression of miR-145, miR-155 and let-7c showed significantly reduced expression in patients with CAD compared to controls. Multivariate logistic regression analysis revealed that low levels of circulating let-7c, miR-145 and miR-155 were associated with CAD. Receiver operating curves analysis showed that let-7c, miR-145 or miR-155 were powerful markers for detecting CAD. Furthermore, we demonstrated that the combination of the three circulating miRNA managed to deliver a specific signature for diagnosing CAD.

Comparison of simple sucrose and percoll based methodologies for synaptosome enrichment

Synaptosomes are isolated nerve terminals. They represent an extremely attractive in vitro model system to study synaptic physiology since they preserve morphological and functional characteristics of the synapse. As such they have been used to investigate synaptic dysfunctions associated with neuropathologies like Alzheimer's disease. In the present work two simple methodologies for isolating synaptosomal-enriched fractions were compared for the first time. The starting points of both protocols were rat cortical or hippocampal homogenized tissues that underwent several differential centrifugation steps followed by a final purification of synaptosomal-enriched fractions using either a Percoll gradient or a Sucrose gradient. Comparison of the fractions obtained was carried out, using both biochemical and electron microscopy approaches. In the biochemical analysis the protein levels of pre-synaptic, post-synaptic, nuclear and mitochondrial markers were evaluated. Additional characterization of the synaptosomal-enriched fractions was performed using transmission electron microscopy. In summary, the results indicate that under the conditions tested the Sucrose based protocol is more efficient for the isolation of synaptosomal-enriched fractions from both neuronal tissues, being particularly efficient for hippocampus that is a less abundant brain tissue. Further, the sucrose protocol apparently results in a higher yield of viable synaptosomes suitable for further assays, including structural and functional studies of synapses; making this an attractive procedure to study processes associated with neuropathologies.

Electron Phase Shift at the Zero-Bias Anomaly of Quantum Point Contacts

The Kondo effect is the many-body screening of a local spin by a cloud of electrons at very low temperature. It has been proposed as an explanation of the zero-bias anomaly in quantum point contacts where interactions drive a spontaneous charge localization. However, the Kondo origin of this anomaly remains under debate, and additional experimental evidence is necessary. Here we report on the first phase-sensitive measurement of the zero-bias anomaly in quantum point contacts using a scanning gate microscope to create an electronic interferometer. We observe an abrupt shift of the interference fringes by half a period in the bias range of the zero-bias anomaly, a behavior which cannot be reproduced by single-particle models. We instead relate it to the phase shift experienced by electrons scattering off a Kondo system. Our experiment therefore provides new evidence of this many-body effect in quantum point contacts.

Genetic diversity, linkage disequilibrium and power of a large grapevine (Vitis vinifera L) diversity panel newly designed for association studies

BACKGROUND

As for many crops, new high-quality grapevine varieties requiring less pesticide and adapted to climate change are needed. In perennial species, breeding is a long process which can be speeded up by gaining knowledge about quantitative trait loci linked to agronomic traits variation. However, due to the long juvenile period of these species, establishing numerous highly recombinant populations for high resolution mapping is both costly and time-consuming. Genome wide association studies in germplasm panels is an alternative method of choice, since it allows identifying the main quantitative trait loci with high resolution by exploiting past recombination events between cultivars. Such studies require adequate panel design to represent most of the available genetic and phenotypic diversity. Assessing linkage disequilibrium extent and panel power is also needed to determine the marker density required for association studies.

RESULTS

Starting from the largest grapevine collection worldwide maintained in Vassal (France), we designed a diversity panel of 279 cultivars with limited relatedness, reflecting the low structuration in three genetic pools resulting from different uses (table vs wine) and geographical origin (East vs West), and including the major founders of modern cultivars. With 20 simple sequence repeat markers and five quantitative traits, we showed that our panel adequately captured most of the genetic and phenotypic diversity existing within the entire Vassal collection. To assess linkage disequilibrium extent and panel power, we genotyped single nucleotide polymorphisms: 372 over four genomic regions and 129 distributed over the whole genome. Linkage disequilibrium, measured by correlation corrected for kinship, reached 0.2 for a physical distance between 9 and 458 Kb depending on genetic pool and genomic region, with varying size of linkage disequilibrium blocks. This panel achieved reasonable power to detect associations between traits with high broad-sense heritability (> 0.7) and causal loci with intermediate allelic frequency and strong effect (explaining > 10 % of total variance).

CONCLUSIONS

Our association panel constitutes a new, highly valuable resource for genetic association studies in grapevine, and deserves dissemination to diverse field and greenhouse trials to gain more insight into the genetic control of many agronomic traits and their interaction with the environment.

Oral chronic GVHD outcomes and resource utilization: a subanalysis from the chronic GVHD consortium

OBJECTIVES

This study evaluated the extent to which oral chronic graft-versus-host disease (cGVHD) consensus assessments are predictive of management across institutions with and without oral medicine (OM) centers, and whether ancillary care guidelines are followed within clinical practice.

METHODS

Longitudinal oral cGVHD data were abstracted from the cGVHD Consortium, and additional mouth-specific management data were analyzed across five transplant centers.

RESULTS

Seventy-nine patients with 656 visits were observed for a median of 7.1 months with one visit per follow-up month. Ancillary therapies for oral cGVHD were prescribed for 67% of patients for a median of 0.46 months (per follow-up month) at OM centers and 0.78 months at non-OM centers. Patients treated with ancillary therapy were more likely to have an National Institutes of Health (NIH) mouth score of ≥1 (P < 0.001, odds ratio: 5.1) and mouth pain (P = 0.01, odds ratio: 2.6). The odds ratios of receiving ancillary therapy from OM experts were higher than transplant physicians (53%; P = 0.03).

CONCLUSIONS

Oral cGVHD consensus assessments corresponding with ancillary therapy use were mouth pain and NIH mouth score, with higher odds ratios of receiving therapy from OM experts. Ancillary care guidelines for oral cGVHD are reflected in academic clinical practice with respect to utilization of recommended prescriptions.

Unravelling the relationship between protein sequence and low-complexity regions entropies: Interactome implications

Low-complexity regions are sub-sequences of biased composition in a protein sequence. The influence of these regions over protein evolution, specific functions and highly interactive capacities is well known. Although protein sequence entropy has been largely studied, its relationship with low-complexity regions and the subsequent effects on protein function remains unclear. In this work we propose a theoretical and empirical model integrating the sequence entropy with local complexity parameters. Our results indicate that the protein sequence entropy is related with the protein length, the entropies inside and outside the low-complexity regions as well as their number and average size. We found a small but significant increment in the sequence entropy of hubs proteins. In agreement with our theoretical model, this increment is highly dependent of the balance between the increment of protein length and average size of the low-complexity regions. Finally, our models and proteins analysis provide evidence supporting that modifications in the average size is more relevant in hubs proteins than changes in the number of low-complexity regions.

Salivary MicroRNA in Pancreatic Cancer Patients

Background

Pancreatic cancer is the fourth leading cause of cancer death in Western countries, with the lowest 1-year survival rate among commonly diagnosed cancers. Reliable biomarkers for pancreatic cancer diagnosis are lacking and are urgently needed to allow for curative surgery. As microRNA (miRNA) recently emerged as candidate biomarkers for this disease, we explored in the present pilot study the differences in salivary microRNA profiles between patients with pancreatic tumors that are not eligible for surgery, precancerous lesions, inflammatory disease or cancer-free patients as a potential early diagnostic tool.

Methods

Whole saliva samples from patients with pancreatic cancer (n = 7), pancreatitis (n = 4), IPMN (n = 2), or healthy controls (n = 4) were obtained during endoscopic examination. After total RNA isolation, expression of 94 candidate miRNAs was screened by q(RT)PCR using Biomark Fluidgm. Human-derived pancreatic cancer cells were xenografted in athymic mice as an experimental model of pancreatic cancer.

Results

We identified hsa-miR-21, hsa-miR-23a, hsa-miR-23b and miR-29c as being significantly upregulated in saliva of pancreatic cancer patients compared to control, showing sensitivities of 71.4%, 85.7%, 85,7% and 57%, respectively and excellent specificity (100%). Interestingly, hsa-miR-23a and hsa-miR23b are overexpressed in the saliva of patients with pancreatic cancer precursor lesions. We found that hsa-miR-210 and let-7c are overexpressed in the saliva of patients with pancreatitis as compared to the control group, with sensitivity of 100% and 75%, and specificity of 100% and 80%, respectively. Last hsa-miR-216 was upregulated in cancer patients as compared to patients diagnosed with pancreatitis, with sensitivity of 50% and specificity of 100%. In experimental models of PDAC, salivary microRNA detection precedes systemic detection of cancer cells markers.

Conclusions

Our novel findings indicate that salivary miRNA are discriminatory in pancreatic cancer patients that are not eligible for surgery. In addition, we demonstrate in experimental models that salivary miRNA detection precedes systemic detection of cancer cells markers. This study stems for the use of salivary miRNA as biomarker for the early diagnosis of patients with unresectable pancreatic cancer.

First-in-man phase 1 clinical trial of gene therapy for advanced pancreatic cancer: safety, biodistribution, and preliminary clinical findings

This phase 1 trial was aimed to determine the safety, pharmacokinetics, and preliminary clinical activity of CYL-02, a nonviral gene therapy product that sensitizes pancreatic cancer cells to chemotherapy. CYL-02 was administrated using endoscopic ultrasound in 22 patients with pancreatic cancer that concomitantly received chemotherapy (gemcitabine). The maximum-tolerated dose (MTD) exceeded the maximal feasible dose of CYL-02 and was not identified. Treatment-related toxicities were mild, without serious adverse events. Pharmacokinetic analysis revealed a dose-dependent increase in CYL-02 DNA exposure in blood and tumors, while therapeutic RNAs were detected in tumors. No objective response was observed, but nine patients showed stable disease up to 6 months following treatment and two of these patients experienced long-term survival. Panels of plasmatic microRNAs and proteins were identified as predictive of gene therapy efficacy. We demonstrate that CYL-02 nonviral gene therapy has a favorable safety profile and is well tolerated in patients. We characterize CYL-02 biodistribution and demonstrate therapeutic gene expression in tumors. Treated patients experienced stability of disease and predictive biomarkers of response to treatment were identified. These promising results warrant further evaluation in phase 2 clinical trial.

Specific macrophage subtypes influence the progression of rhabdomyolysis-induced kidney injury

Rhabdomyolysis can be life threatening if complicated by AKI. Macrophage infiltration has been observed in rat kidneys after glycerol-induced rhabdomyolysis, but the role of macrophages in rhabdomyolysis-induced AKI remains unknown. Here, in a patient diagnosed with rhabdomyolysis, we detected substantial macrophage infiltration in the kidney. In a mouse model of rhabdomyolysis-induced AKI, diverse renal macrophage phenotypes were observed depending on the stage of the disease. Two days after rhabdomyolysis, F4/80(low)CD11b(high)Ly6b(high)CD206(low) kidney macrophages were dominant, whereas by day 8, F4/80(high)CD11b(+)Ly6b(low)CD206(high) cells became the most abundant. Single-cell gene expression analyses of FACS-sorted macrophages revealed that these subpopulations were heterogeneous and that individual cells simultaneously expressed both M1 and M2 markers. Liposomal clodronate-mediated macrophage depletion significantly reduced the early infiltration of F4/80(low)CD11b(high)Ly6b(high)CD206(low) macrophages. Furthermore, transcriptionally regulated targets potentially involved in disease progression, including fibronectin, collagen III, and chemoattractants that were identified via single-cell analysis, were verified as macrophage-dependent in situ. In vitro, myoglobin treatment induced proximal tubular cells to secrete chemoattractants and macrophages to express proinflammatory markers. At day 30, liposomal clodronate-mediated macrophage depletion reduced fibrosis and improved both kidney repair and mouse survival. Seven months after rhabdomyolysis, histologic lesions were still present but were substantially reduced with prior depletion of macrophages. These results suggest an important role for macrophages in rhabdomyolysis-induced AKI progression and advocate the utility of long-term follow-up for patients with this disease.

[Thrombotic microangiopathy: when time is the key factor!]

Thrombotic microangiopathy or "TMA" including thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS) became a public health problem following the European outbreak of E. coli (O104:H4) gastroenteritis in 2011. A rapid diagnosis and therapy in an intensive care unit provide better patient survival and lower cost for society. Supportive treatment has significantly improved the prognosis over the past decade and includes fresh frozen plasma for TTP, plasmapheresis for HUS, and recently a new therapeutic agent: anti-C5 antibodies. We will provide in this article, through the current literature and four cases encountered in our department, to establish an algorithm to manage patients with TMA.