Adipocyte-derived inflammatory molecules induce senescent B cells through metabolic pathways

OBJECTIVE

The aim of this study was to demonstrate that an adipocyte tissue-derived conditioned medium (ACM) contains inflammatory molecules that induce senescence in B cells.

METHODS

We incubated blood-derived B cells from lean donors with ACM obtained from the adipose tissue of adult female donors with obesity undergoing weight reduction surgery or with medium as control. After 24 h, cells were harvested, and the expression of transcripts for proinflammatory cytokines (TNF/IL-6), chemokines (IL-8), and for markers of the senescence-associated secretory phenotype (SASP) was measured by quantitative polymerase chain reaction. B cells were also stained with the marker of immunosenescence β-galactosidase, and their metabolic status was evaluated in Seahorse using a Mito Stress Test.

RESULTS

We show that the incubation of B cells from lean donors with ACM induces the expression of transcripts for inflammatory and SASP transcripts, increases the amount of β-galactosidase staining, and induces a metabolic phenotype characterized by higher basal and maximal oxygen consumption, spare respiratory capacity (difference between maximal and basal respiration), nonmitochondrial oxygen consumption, ATP production, and proton leak.

CONCLUSIONS

These results demonstrate that B cells from lean individuals, after incubation with ACM, become inflammatory and senescent, and this occurs through metabolic pathways needed to support their secretory phenotype.

Synthesis and characterization of a bovine collagen: GAG scaffold with Uruguayan raw material for tissue engineering

Tissue engineering (TE) and regenerative medicine offer strategies to improve damaged tissues by using scaffolds and cells. The use of collagen-based biomaterials in the field of TE has been intensively growing over the past decades. Mesenchymal stromal cells (MSCs) and dental pulp stem cells (DPSCs) are promising cell candidates for development of clinical composites. In this study, we proposed the development of a bovine collagen type I: chondroitin-6-sulphate (CG) scaffold, obtained from Uruguayan raw material (certified as free bovine spongiform encephalopathy), with CG crosslinking enhancement using different gamma radiation doses. Structural, biomechanical and chemical characteristics of the scaffolds were assessed by Scanning Electron Microscopy, axial tensile tests, FT-IR and Raman Spectroscopy, respectively. Once we selected the most appropriate scaffold for future use as a TE product, we studied the behavior of MSCs and DPSCs cultured on the scaffold by cytotoxicity, proliferation and differentiation assays. Among the diverse porous scaffolds obtained, the one with the most adequate properties was the one exposed to 15 kGy of gamma radiation. This radiation dose contributed to the crosslinking of molecules, to the formation of new bonds and/or to the reorganization of the collagen fibers. The selected scaffold was non-cytotoxic for the tested cells and a suitable substrate for cell proliferation. Furthermore, the scaffold allowed MSCs differentiation to osteogenic, chondrogenic, and adipogenic lineages. Thus, this work shows a promising approach to the synthesis of a collagen-scaffold suitable for TE.

Theory of mind in neurodevelopmental disorders: beyond autistic spectrum disorder

INTRODUCTION

Theory of mind (ToM) is the human ability to perceive, interpret, and attribute the mental states of other people, and the alteration of this cognitive function is a core symptom of autistic spectrum disorder (ASD). In such other neurodevelopmental disorders as childhood-onset obsessive-compulsive disorder (OCD) and Tourette syndrome (TS) that can present with cognitive dysfunctions, ToM has been less extensively studied, especially in the young population. The aim of the study was to compare advanced ToM between groups of young people diagnosed with OCD, TS, or ASD and a control group.

METHODS

Clinical interviews were conducted with male patients aged between 11 and 17 years with a main diagnosis of OCD (n = 19), TS (n = 14), or ASD (n = 18), and a control group (n = 20). We administered instruments for estimating intelligence quotient and severity of psychiatric symptoms, and tasks to evaluate ToM (the "Stories from everyday life" task and the "Reading the mind in the eyes" test).

RESULTS

Young people with TS and with ASD present similar difficulties in solving advanced ToM tasks, whereas patients with childhood-onset OCD present similar results to controls.

CONCLUSIONS

ToM is altered in other neurodevelopmental disorders beyond ASD, such as TS.

Consensus statement on the processing, interpretation and reporting of temporal artery biopsy for arteritis

Giant cell arteritis (GCA) is the most common systemic vasculitis in adults in Europe and North America, typically involving the extra-cranial branches of the carotid arteries and the thoracic aorta. Despite advances in noninvasive imaging, temporal artery biopsy (TAB) remains the gold standard for establishing a GCA diagnosis. The processing of TAB depends largely on individual institutional protocol, and the interpretation and reporting practices vary among pathologists. To address this lack of uniformity, the Society for Cardiovascular Pathology formed a committee tasked with establishing consensus guidelines for the processing, interpretation, and reporting of TAB specimens, based on the existing literature. This consensus statement includes a discussion of the differential diagnoses including other forms of arteritis and noninflammatory changes of the temporal artery.

Immunometabolic effects of lactate on B cell function in healthy individuals of different ages

Aging is characterized by chronic systemic inflammation and metabolic changes. When we compared B cells from young and elderly donors, we found that aging induces higher oxygen consumption rates, and especially higher extracellular acidification rates, measures of oxidative phosphorylation and of anaerobic glycolysis, respectively. Importantly, this higher metabolic status, which reflects the age-associated expansion of pro-inflammatory B cell subsets, was found associated with higher secretion of lactate and autoimmune antibodies after in vitro stimulation. B cells from elderly individuals, induce in vitro generation of pro-inflammatory CD4+ T cells from young individuals through metabolic pathways mediated by lactate secretion. Lactate also induces immunosenescent B cells that are glycolytic and express transcripts for multiple pro-inflammatory molecules. These results altogether may have relevant clinical implications and suggest novel targets for therapeutic interventions in patients with inflammatory conditions and diseases.

Obesity accelerates age defects in B cells, and weight loss improves B cell function

BACKGROUND

We have previously shown that obesity accelerates age-associated defects in B cell function and antibody production leading to decreased secretion of protective antibodies and increased autoimmunity. We wanted to evaluate if obese adults enrolled in a voluntary weight reduction program had higher protective and lower autoimmune antibody responses similar to those observed in lean adults.

METHODS

Experiments were performed using blood isolated from an established cohort of female lean adult and elderly individuals, as well as from the blood of female adults with obesity, before and after a voluntary weight reduction program in which their Body Mass Index (BMI) was reduced 10-34% in 12 months. All participants were vaccinated with the Trivalent Inactivated Influenza vaccine. Serum samples were evaluated for the presence of pro-inflammatory cytokines and adipokines, vaccine-specific antibodies and autoimmune antibodies. We evaluated the composition of the B cell pool by flow cytometry, the expression of RNA for class switch transcription factors and pro-inflammatory markers by qPCR, the in vitro secretion of pro- and anti-inflammatory cytokines and their capacity to induce pro-inflammatory T cells.

RESULTS

Obesity, similar to aging, induced increased serum levels of pro-inflammatory cytokines and autoimmune antibodies, while vaccine-specific antibodies were reduced. In agreement with the serum results, the B cell pool of obese adults and elderly individuals was enriched in pro-inflammatory B cell subsets and was characterized by higher expression of markers associated with cell senescence, higher levels of T-bet, the transcription factor for autoimmune antibodies and lower levels of E47, the transcription factor associated with protective responses to the influenza vaccine. B cells from obese adults and elderly individuals were also able to secrete inflammatory cytokines and support the generation of inflammatory T cells. All these pro-inflammatory characteristics of B cells from obese individuals were significantly attenuated, but not completely reversed, by weight loss.

CONCLUSIONS

Although the results from our small observational study show that obesity-induced dysfunctional B cell responses, similar to those occurring during aging, are ameliorated in some but not all obese individuals after weight loss, the effects of body weight loss on mechanistic pathways are largely missing and deserve further investigation.

Sudden cardiac death in the young: A consensus statement on recommended practices for cardiac examination by pathologists from the Society for Cardiovascular Pathology

Sudden cardiac death is, by definition, an unexpected, untimely death caused by a cardiac condition in a person with known or unknown heart disease. This major international public health problem accounts for approximately 15-20% of all deaths. Typically more common in older adults with acquired heart disease, SCD also can occur in the young where the cause is more likely to be a genetically transmitted process. As these inherited disease processes can affect multiple family members, it is critical that these deaths are appropriately and thoroughly investigated. Across the United States, SCD cases in those less than 40 years of age will often fall under medical examiner/coroner jurisdiction resulting in scene investigation, review of available medical records and a complete autopsy including toxicological and histological studies. To date, there have not been consistent or uniform guidelines for cardiac examination in these cases. In addition, many medical examiner/coroner offices are understaffed and/or underfunded, both of which may hamper specialized examinations or studies (e.g., molecular testing). Use of such guidelines by pathologists in cases of SCD in decedents aged 1-39 years of age could result in life-saving medical intervention for other family members. These recommendations also may provide support for underfunded offices to argue for the significance of this specialized testing. As cardiac examinations in the setting of SCD in the young fall under ME/C jurisdiction, this consensus paper has been developed with members of the Society of Cardiovascular Pathology working with cardiovascular pathology-trained, practicing forensic pathologists.

Phenotypic and functional features of B cells from two different human subcutaneous adipose depots

In this study, we have compared frequencies, phenotype, function and metabolic requirements of B cells isolated from the breast and abdominal subcutaneous adipose tissue (AT) of women with obesity who underwent weight reduction surgeries. Results show that B cells from the abdominal AT are more inflammatory than those from the breast, characterized by higher frequencies of inflammatory B cell subsets and higher expression of RNA for inflammatory markers associated with senescence. Secretion of autoimmune antibodies is also higher in the abdominal AT as compared to the breast, and is associated with higher frequencies of autoimmune B cells with the membrane phenotype CD21lowCD95+ B cells expressing the transcription factor T-bet. Moreover, glucose uptake is higher in B cells from the abdominal AT as compared to the breast, thereby suggesting a better capacity to perform glycolysis, needed to support intrinsic B cell inflammation and autoimmune antibody secretion.

B cells from old mice induce the generation of inflammatory T cells through metabolic pathways

We have measured the capacity of B cells from young and old mice to induce the differentiation of naïve CD4 + T cells from young mice into pro-inflammatory subsets. We found that only B cells from old mice are inflammatory and induce in vitro secretion of the pro-inflammatory cytokines IL-17A and IFN-γ by T cells. In co-culture experiments, B cells from old mice showed a strong helper function on T cells from young mice, making them pro-inflammatory, and this effect is regulated by metabolic pathways, mainly anaerobic glycolysis, leading to increased RNA expression of the enzyme lactate dehydrogenase (LDHA) and increased secretion of lactate. These results have indicated that lactate is a crucial player of the B cell-induced polarization of T cells. When we measured the effects of lactate on isolated CD4 + T cells from young mice, we found that lactate increases RNA expression of LDHA, secretion of pro-inflammatory cytokines and NF-kB activation. Moreover, lactate effects in culture can be abrogated in the presence of the specific inhibitor of LDHA, FX11. These results altogether may have relevant clinical implications and suggest novel targets for therapeutic interventions in patients with inflammatory conditions and diseases.

Female sex workers and police violence during the Covid-19 health crisis in 2020-2021: results from the EPIC multi-country community-based research program in Argentina

BACKGROUND

Female sex workers (FSW) have been disproportionately impacted by the Covid-19 crisis. Data show increases of police violence toward key populations (KP), likely a consequence of their role in enforcing health government measures. This study aimed to identify factors associated with police violence experienced by FSW during the Covid-19 crisis in Argentina.

METHODS

EPIC is a multi-country, cross-sectional, community-based research program evaluating the impact of Covid-19 among KP. In Argentina, the study was conducted in collaboration with FSW community-based organizations (CBO). Participants completed an online survey (October 2020-April 2021). Police violence was measured as having experienced episodes of violence (physical, verbal, psychological or sexual) by security forces since the start of the health crisis. Factors associated with police violence were assessed in logistic regression models.

RESULTS

Among 173 respondents, median age was 34 [IQR 27-42], 39.3% were transgender women (TW), 78.1% declared sex work as their only income and 71.7% mentioned their financial situation has deteriorated with the health crisis. Nearly half of FSW (44.5%) reported experiencing police violence within the first year of the Covid-19 pandemic, and among them, 76.6% declared more frequent violence episodes since the beginning of the health crisis. After adjustment for age, being a TW (aOR [95% CI] = 2.71 [1.21;6.05]), reporting non-injection drug use (2.92 [1.02;8.36]), having a considerably deteriorated financial situation (3.67 [1.47;9.21]), having had a consultation with a CBO worker for medical care/treatments (5.56 [2.15;14.37]) and declaring fear or experiences of discrimination by physicians/other health workers (2.97 [1.21;7.29]), since the beginning of the Covid-19 health crisis, were independently associated with police violence.

CONCLUSIONS

FSW in Argentina have experienced an increase in police violence since the beginning of the health crisis. Belonging to multiple KP (FSW, TW, people who use drugs) increases the likelihood of experiencing police violence, highlighting the need of an intersectional approach to develop interventions to reduce stigma and violence against FSW. CBOs have provided essential support and services during the crisis to FSWs, and other KPs, who may have avoided traditional healthcare structures due to fear or experiences of discrimination.

Translational challenges and opportunities in biofilm science: a BRIEF for the future

Biofilms are increasingly recognised as a critical global issue in a multitude of industries impacting health, food and water security, marine sector, and industrial processes resulting in estimated economic cost of $5 trillion USD annually. A major barrier to the translation of biofilm science is the gap between industrial practices and academic research across the biofilms field. Therefore, there is an urgent need for biofilm research to notice and react to industrially relevant issues to achieve transferable outputs. Regulatory frameworks necessarily bridge gaps between different players, but require a clear, science-driven non-biased underpinning to successfully translate research. Here we introduce a 2-dimensional framework, termed the Biofilm Research-Industrial Engagement Framework (BRIEF) for classifying existing biofilm technologies according to their level of scientific insight, including the understanding of the underlying biofilm system, and their industrial utility accounting for current industrial practices. We evidence the BRIEF with three case studies of biofilm science across healthcare, food & agriculture, and wastewater sectors highlighting the multifaceted issues around the effective translation of biofilm research. Based on these studies, we introduce some advisory guidelines to enhance the translational impact of future research.

Metformin Enhances B Cell Function and Antibody Responses of Elderly Individuals With Type-2 Diabetes Mellitus

Our previous work has shown that young and elderly patients with Type-2 Diabetes Mellitus (T2DM) treated with Metformin have optimal B cell function and serum antibodies specific for the seasonal influenza vaccine. In this paper, we have evaluated B cell function and the metabolic requirements of B cell antibody responses in elderly T2DM patients (E_T2DM) taking or not Metformin, and compared to those of healthy elderly (E_H) and healthy young (Y_H) individuals. Results show that Metformin significantly increases in vivo B cell function, measured by influenza vaccine-specific serum antibodies, in E_T2DM patients to the levels observed in E_H and more importantly in Y_H individuals. Metformin also decreases the frequencies of pro-inflammatory B cell subsets, as well as intrinsic inflammation and metabolic requirements of peripheral B cells from E_T2DM. This hyper-metabolic phenotype of B cells from E_T2DM is needed to support intrinsic inflammation, measured by the expression of transcripts for markers of the senescence-associated secretory phenotype (SASP), and the secretion of autoimmune antibodies. Importantly, B cell function in E_T2DM patients taking Metformin is not only increased as compared to that in E_T2DM patients not taking Metformin, but is comparable to B cell function measured in Y_H individuals. These results altogether strongly support the anti-aging effects of Metformin on humoral immunity.

Old mice and elderly humans make increased autoimmune antibodies, inflammation and SASP from aged-increased B cells (ABCs in mice and DN in humans) which are hypermetabolic

Immune mechanisms of human and murine diseases of aging include generation of chronic inflammation and autoimmunity. We and others have associated aging in mice and humans with increased chronic inflammation, reduced vaccine response and an increase in a B lymphocyte subset referred to as Age-associated B cells (ABCs) in mice and DN (double negative) in humans. Immune cell function is dependent on metabolic pathways and to date understudied. A. In this work we sorted splenic ABCs (CD19+AA4.1-CD21-CD23−) from young (3–4 months) and old (18–22 months) C57BL/6 mice showing an increased percentage in old and increased RNA expression of SASP (senescence-associated secretory phenotype) pro-inflammatory cytokines (TNFa, IL-6), proinflammatory micro-RNAs (miRs 155 and 16) and cell cycle regulators p16INK4 and p21Waf1 in old ABCs. We also show here old B cells produce more autoimmune IgG antibodies (to MDA, malondialdehyde and ADA, adipocyte-derived antigens), ABCs more than FO (follicular), and ABCs from old more than those from young. Total B cells and ABCs from old mice also have a higher metabolic profile compared with those of young mice. B. The frequency of DN cells is increased in human elderly as well as those younger with obesity. Plasma of obese had more autoantibodies to dsDNA, MDA, and ADA and the DN B cells showed higher levels of IA (Immune activation) markers and transcription factors, e.g. tbx21 (TBET) associated with autoimmunity. We have recently found that elderly human B cells are, like murine, hypermetabolic and are discovering possible mechanisms, such as fatty acids.

Supported by grants from NIH (AG32576, AG059719, and AG023717)

Fluid dynamics and cell‐bound Psl polysaccharide allows microplastic capture, aggregation and subsequent sedimentation by Pseudomonas aeruginosa in water

Decades after incorporating plastics into consumer markets, research shows that these polymers have spread worldwide. Fragmentation of large debris leads to smaller particles, collectively called microplastics (MPs), which have become ubiquitous in aquatic environments. A fundamental aspect of understanding the implications of MP contamination on ecosystems is resolving the complex interactions of these artificial substrates with microbial cells. Using polystyrene microparticles as model polymers, we conducted an exploratory study where these interactions are quantitatively analyzed using an in vitro system consisting of single‐bacterial species capturing and aggregating MPs in water. Here we show that the production of Psl exopolysaccharide by Pseudomonas aeruginosa (PA) does not alter MPs colloidal stability but plays a key role in microspheres adhesion to the cell surface. Further aggregation of MPs by PA cells depends on bacterial mobility and the presence of sufficient flow to prevent rapid sedimentation of early MP‐PA assembles. Surprisingly, cells in MP‐PA aggregates are not in a sessile state despite the production of Psl, enhancing the motility of the aggregates by an order of magnitude relative to passive diffusion. The generated data could inform the creation of predictive models that accurately describe the dynamics and influence of bacterial growth on plastics debris.

Obesity Accelerates Age-Associated Defects in Human B Cells Through a Metabolic Reprogramming Induced by the Fatty Acid Palmitate

We have measured the secretion of autoimmune antibodies in plasma samples and in culture supernatants of blood-derived B cells from four groups of individuals: young lean (Y_L), elderly lean (E_L), young obese (Y_O) and elderly obese (E_O). We found secretion comparable in Y_O and E_L individuals, suggesting that obesity accelerates age-associated defects in circulating B cells. To define at least one possible molecular pathway involved, we used an in vitro model in which B cells from Y_L and E_L individuals have been stimulated with the Fatty Acid (FA) palmitate, the most common saturated FA in the human body. The rationale to use palmitate is that there is a chronic increase in circulating levels of palmitate, due to increased spontaneous lipolysis occurring during aging and obesity, and this may induce autoimmune B cells. Results herein show that in vitro incubation of B cells from Y_L and E_L individuals with the FA palmitate induces mRNA expression of T-bet, the transcription factor for autoimmune antibodies, as well as secretion of autoimmune IgG antibodies, with B cells from Y_L individuals looking similar to B cells from E_L individuals, confirming our initial hypothesis. The generation of autoimmune B cells in the presence of the FA palmitate was found to be associated with a metabolic reprogramming of B cells from both Y_L and E_L individuals. These results altogether show the critical role of the FA palmitate in inducing human B cell immunosenescence and show for the first time the importance of metabolic pathways in this process.

The majority of SARS-CoV-2-specific antibodies in COVID-19 patients with obesity are autoimmune and not neutralizing

BACKGROUND/OBJECTIVES

Obesity decreases the secretion of SARS-CoV-2-specific IgG antibodies in the blood of COVID-19 patients. How obesity impacts the quality of the antibodies secreted, however, is not understood. Therefore, the objective of this study is to evaluate the presence of neutralizing versus autoimmune antibodies in COVID-19 patients with obesity.

SUBJECTS/METHODS

Thirty serum samples from individuals who tested positive for SARS-CoV-2 infection by RT-PCR were collected from inpatient and outpatient settings. Of these, 15 were lean (BMI < 25) and 15 were obese (BMI ≥ 30). Control serum samples were from 30 uninfected individuals, age-, gender-, and BMI-matched, recruited before the current pandemic. Neutralizing and autoimmune antibodies were measured by ELISA. IgG autoimmune antibodies were specific for malondialdehyde (MDA), a marker of oxidative stress and lipid peroxidation, and for adipocyte-derived protein antigens (AD), markers of virus-induced cell death in the obese adipose tissue.

RESULTS

SARS-CoV-2 infection induces neutralizing antibodies in all lean but only in few obese COVID-19 patients. SARS-CoV-2 infection also induces anti-MDA and anti-AD autoimmune antibodies more in lean than in obese patients as compared to uninfected controls. Serum levels of these autoimmune antibodies, however, are always higher in obese versus lean COVID-19 patients. Moreover, because the autoimmune antibodies found in serum samples of COVID-19 patients have been correlated with serum levels of C-reactive protein (CRP), a general marker of inflammation, we also evaluated the association of anti-MDA and anti-AD antibodies with serum CRP and found a positive association between CRP and autoimmune antibodies.

CONCLUSIONS

Our results highlight the importance of evaluating the quality of the antibody response in COVID-19 patients with obesity, particularly the presence of autoimmune antibodies, and identify biomarkers of self-tolerance breakdown. This is crucial to protect this vulnerable population at higher risk of responding poorly to infection with SARS-CoV-2 than lean controls.

Reliability and validity of the Mexican teachers' physical activity questionnaire (MTPAQ) in a subsample of female Mexican teachers

BACKGROUND

Reliable and valid instruments are needed to estimate physical activity levels. The purposes of this study were to estimate the reliability and validity of the Physical Activity Questionnaire (MTPAQ) in a subsample of the Mexican Teachers Cohort study.

METHODS

We completed telephone interviews and clinical examinations of 82 teachers. Two MTPAQ, five International Physical Activity Questionnaire (IPAQ)-long form, and two accelerometer (AC) measures were used to determine physical activity levels throughout 24 months. Moderate and walking physical activity (MWPA min/week), vigorous physical activity (VPA min/week), and moderate-to-vigorous physical activity minutes per week (MVPA min/week) were estimated for each instrument. Pearson, Intra-class correlations and deattenuated adjustments were used to determine the reliability and validity of MTPAQ.

RESULTS

MWPA and MVPA min/week of MTPAQs were moderately correlated (r ≥ 0.54) to min/week of IPAQ-long form. MWPA and MVPA min/week average MTPAQ and MTPAQ1 and average AC, AC1 and AC2 were fairly correlated (r ≥ 0.20). A higher correlation was observed when correlation coefficients were attenuated (r ≥ 0.32).

CONCLUSIONS

MTPAQ1 is a reliable and valid tool to measure physical activity levels.

Overcrowding and exposure to secondhand smoke increase risk for COVID-19 infection among Latinx families in the greater San Francisco Bay Area

INTRODUCTION

Environmental risk factors, including community level pollution burden and exposure to smoking and secondhand smoke, have not been evaluated in relation to risk for infection with COVID-19 in high risk, urban Latinx families.

METHODS

We evaluated risk factors for COVID-19 infection in three, preexisting, longitudinal, Latinx family cohorts in the San Francisco Bay Area from May through September 2020 (N=383 households, 1875 people). All households were previously recruited before the pandemic. For the COVID-19 sub-study, participants responded to a telephone interview where we assessed food consumption patterns, housing and employment status, and history of COVID-19 infection. Secondhand smoke exposure was based on previously collected selfreported data, and environmental pollution exposure was determined from census tract residence. Non-parametric tests and multiple logistic regression were used to assess independent predictors of COVID-19 infection.

RESULTS

Larger household size increased risk for infection (OR=1.58; 95% CI: 1.12–2.23, p<0.01) as did increasing number of children in household (OR=3.79; 95% CI: 1.51–9.56). Any exposure to secondhand smoke was also associated with increased risk for COVID infection (OR 4.69; 95% CI: 1.01–21.85) and having a greater number of family members eating at home was protective against infection (OR=0.10; 95% CI: 0.02–0.52, p<0.01).

CONCLUSIONS

Crowding, as indicated by larger household size, increases risk for COVID-19 infection in Latinx families, as does exposure to secondhand smoke. Public policy and health interventions need to ensure that multiunit residential complexes do not allow exposure to secondhand smoke between units, that individuals eat in the home environment, and that large households can safely separate individuals exposed to COVID-19.

Linear energy transfer characterization of five gel dosimeter formulations for electron and proton therapeutic beams

Gel dosimeters, including radiochromic types like Fricke, as well as polymer formulations, are considered to be the only reliable option for accurate 3D dosimetry. Nevertheless, their implementation in daily clinical quality assurance still remains strongly limited for a few high specialized radiotherapy centres. Although gel dosimeters present very good water-equivalence due to their inherent chemical and isotopic compositions, addressing the corresponding dosimetry outputs is highly challenging, needing careful assessment in terms of the different radiation qualities involved in the mixed field. Accurate estimations of the linear energy transfer for each gel dosimeter formulation stands as a baseline for further accurate dose deconvolution in mixed radiation fields. The present study reports on the linear energy transfer characterization of five different gel dosimeter formulations, Fricke, Itabis, Magic, Nipam, and Pagat, for electron and proton therapeutic beams as obtained by Monte Carlo approaches, along with experimental results for validation purposes. The linear energy transfer, as a function of beam quality and penetration depth, is obtained for electron and proton therapeutic beams remarking the presence of non-negligible variations, which need to be accounted for a further accurate implementation of gel dosimetry as well as for precise dose deconvolution in mixed radiation fields.

Association between distance to tertiary hospital and cardiovascular outcomes in coronary artery disease patients

Background

The impact of distance from residence to Tertiary Referral Hospital and cardiovascular (CV) outcomes in patients with coronary artery disease (CAD) is unknow. Despite longer travel distances hinder access to healthcare and may worsen CV outcomes, we hypothesize that Mediterranean lifestyle and behaviors in distant rural areas may be associated with a reduced risk of CV death and events.

Purpose

To investigate the association between travel distance to Tertiary Hospital and mid-term cardiovascular outcomes in a population of CAD patients in Southern Spain.

Methods

Retrospective study including all patients discharged after percutaneous coronary intervention (PCI) at a high-volume center in Southern Spain during 2018. Those belonging to another healthcare area were excluded. One-way driving distances from residence to hospital were computed using Google Maps Distance Matrix API with R package “gmapsdistance”. Patients were stratified into tertiles according to travel distance (short, STD; intermediate, ITD; and long, LTD). Kaplan-Meier (KM) and Multivariable Cox regression (adjusted for age, sex, atrial fibrillation, cancer history, prior revascularization and clinical presentation) were used to assess the impact of travel distance on CV death and a composite outcome of MACE (Myocardial Infarction, unplanned PCI and CV death).

Results

Of 1005 patients discharged after PCI during the study period, 966 met the selection criteria. Flowchart and baseline characteristics by distance groups are presented in Figure 1. Median travel distance tertiles were 6.1 (STD), 41.7 (ITD) and 78.4 (LTD). During a median follow-up of 31 (IQR 28–35) months, 50 cardiovascular deaths [STD 27 (8.4%), ITD 13 (4%), LTD 10 (3.1%), p=0.006)] and 63 MACE occurred [STD 45 (13.9%), ITD 37 (11.5%), LTD 26 (8.1%), p=0.060)]. KM curves for the three distance groups are shown in Figure 2. In univariable and multivariable Cox models, longer travel distances were associated with better outcomes, as for every 10 Km increase, there was a 11% and 7% decrease in the hazards of CV death (HR adj: 0.89, CI 0.82–0.98, p=0.029) and of MACE (HR adj: 0.93, CI 0.87–0.99, p=0.025), respectively.

Conclusion

Travel distance was inversely associated with CV events in a population of CAD patients in Southern Spain. Patients in the first tertile of distance had a higher rate of CV death. Multicenter studies involving other Mediterranean regions are needed to confirm these findings and to look for explanations.

Funding Acknowledgement

Type of funding sources: None. Flowchart and baseline characteristicsSurvival curves by distance groups

Instantaneous wave-free ratio for the assessment of nonculprit lesions in patients with acute coronary syndrome

Background

A physiological assessment with the fractional flow reserve (FFR) or instantaneous wave-free ratio (iFR) is strongly recommended by the European Guidelines of Revascularization to guide percutaneous coronary intervention (PCI) decision making in intermediate coronary stenosis. However, data supporting its use in the pro-inflammatory setting of ACS is weak.

Purpose

To analyze the usefulness of a physiological coronary evaluation with iFR of nonculprit lesions in patients with ACS.

Methods

Retrospective multicenter study including patients with ACS and underwent successful revascularization of the culprit vessel and had other nonculpritlesions physiologically evaluated with the iFR between January 2017 and December 2019. The primary endpoint was a composite of cardiac death, nonfatal myocardial infarction, stent thrombosis and new revascularization (MACEs).

Results

A total of 356 patients with 472 nonculprit lesions were included. The mean age was 66±11 years. The clinical presentation was non-ST-segment elevation myocardial infarction (NSTEMI) in 235 patients and ST-segment elevation myocardial infarction (STEMI) in 121 patients. After a mean follow-up period of 22±10 months, the primary endpoint occurred in 32 patients (9%). There were no differences in outcomes regarding iFR induced treatment strategy (patients with all lesions revascularized vs. patients with at least one lesion deferred for revascularization, 10.5 vs 8.4%, p=0.476).

Conclusion

The use of the iFR to guide percutaneous coronary intervention decision making in nonculprit lesions seems to be safe, with an acceptable percentage of MACEs at the mid-term follow-up.

Funding Acknowledgement

Type of funding sources: None. FlowchartSurvival curves by iFR and ACS group

B Cell Immunosenescence

Innate and adaptive immune responses decline with age, leading to greater susceptibility to infectious diseases and reduced responses to vaccines. Diseases are more severe in old than in young individuals and have a greater impact on health outcomes such as morbidity, disability, and mortality. Aging is characterized by increased low-grade chronic inflammation, so-called inflammaging, that represents a link between changes in immune cells and a number of diseases and syndromes typical of old age. In this review we summarize current knowledge on age-associated changes in immune cells with special emphasis on B cells, which are more inflammatory and less responsive to infections and vaccines in the elderly. We highlight recent findings on factors and pathways contributing to inflammaging and how these lead to dysfunctional immune responses. We summarize recent published studies showing that adipose tissue, which increases in size with aging, contributes to inflammaging and dysregulated B cell function.

Theory of mind in neurodevelopmental disorders: Beyond autistic spectrum disorder

INTRODUCTION

Theory of mind (ToM) is the human ability to perceive, interpret, and attribute the mental states of other people, and the alteration of this cognitive function is a core symptom of autistic spectrum disorder (ASD). In such other neurodevelopmental disorders as childhood-onset obsessive-compulsive disorder (OCD) and Tourette syndrome (TS) that can present with cognitive dysfunctions, ToM has been less extensively studied, especially in the young population. The aim of the study was to compare advanced ToM between groups of young people diagnosed with OCD, TS, or ASD and a control group.

METHODS

Clinical interviews were conducted with male patients aged between 11 and 17 years with a main diagnosis of OCD (n=19), TS (n=14), or ASD (n=18), and a control group (n=20). We administered instruments for estimating intelligence quotient and severity of psychiatric symptoms, and tasks to evaluate ToM (the "Stories from everyday life" task and the "Reading the mind in the eyes" test).

RESULTS

Young people with TS and with ASD present similar difficulties in solving advanced ToM tasks, whereas patients with childhood-onset OCD present similar results to controls.

CONCLUSIONS

ToM is altered in other neurodevelopmental disorders beyond ASD, such as TS.

SARS-CoV-2 infection induces autoimmune antibody secretion more in lean than in obese COVID-19 patients

BACKGROUND/OBJECTIVES

Obesity decreases the secretion of SARS-CoV-2-specific IgG antibodies in the blood of COVID-19 patients. How obesity impacts the secretion of autoimmune antibodies in COVID-19 patients, however, is not understood. The serum of adult COVID-19 patients contains autoimmune antibodies generated in response to virus-induced tissue damage and cell death leading to the release of intracellular antigens not known to be immunogenic autoantigens. The objective of this study is to evaluate the presence of autoimmune antibodies in COVID-19 patients with obesity.

SUBJECTS/METHODS

Thirty serum samples from individuals who tested positive for SARS-CoV-2 infection by RT-PCR were collected from inpatient and outpatient settings. Of these, 15 were lean (BMI<25), and 15 were obese (BMI ≥30). Control serum samples were from 30 uninfected individuals, age-gender- and BMI-matched, recruited before the current pandemic. Serum IgG antibodies against two autoimmune specificities, as well as against SARS-CoV-2 Spike protein, were measured by ELISA. IgG autoimmune antibodies were specific for malondialdehyde (MDA), a marker of oxidative stress and lipid peroxidation, and for adipocyte-derived protein antigens (AD), markers of virus-induced cell death in the obese AT.

RESULTS

Our results show that SARS-CoV-2 infection induces anti-MDA and anti-AD autoimmune antibodies more in lean than in obese patients as compared to uninfected controls. Serum levels of these autoimmune antibodies, however, are always higher in obese versus lean COVID-19 patients. Moreover, because the autoimmune antibodies found in serum samples of COVID-19 patients have been correlated with serum levels of C-reactive protein (CRP), a general marker of inflammation, we also evaluated the association of anti-MDA and anti-AT antibodies with serum CRP and found a significant association between CRP and autoimmune antibodies in our cohort of lean and obese COVID-19 patients.

CONCLUSIONS

Our results highlight the importance of evaluating the quality of the antibody response in COVID-19 patients with obesity, particularly the presence of autoimmune antibodies, and identify biomarkers of self-tolerance breakdown. This is crucial to protect this vulnerable population that is at higher risk of responding poorly to infection with SARS-CoV-2 compared to lean controls.

Obesity effects serum levels of SARS-CoV-2-specific antibodies in COVID-19 patients

SARS-CoV-2 (Severe Acute Respiratory Syndrome Corona Virus-2), cause of COVID-19 (Coronavirus Disease of 2019), represents a significant risk to people living with pre-existing conditions including increased inflammatory responses and consequent dysfunctional immunity.

In these studies we evaluated the effects of obesity, a condition associated with chronic systemic inflammation, on the secretion of SARS-CoV-2-specific IgG antibodies in the blood of COVID-19 patients. Results showed that SARS-CoV-2 IgG antibodies are negatively associated with Body Mass Index (BMI) in COVID-19 obese patients, as expected based on the known effects of obesity on humoral immunity, as we have previously published for the response to the influenza vaccine. Antibodies in COVID-19 obese patients are also negatively associated with serum levels of pro-inflammatory and metabolic markers of inflammaging and pulmonary inflammation, such as SAA (serum amyloid A protein), CRP (C-reactive protein) and ferritin, but positively associated with NEFA (nonesterified fatty acids). These results altogether help to identify an inflammatory signature with strong predictive value for immune dysfunction that could be targeted to improve humoral immunity in individuals with obesity as well as with other chronic inflammatory conditions.

Hyper-metabolic B cells in the spleens of old mice make antibodies with autoimmune specificities

BACKGROUND

Aging is associated with increased intrinsic B cell inflammation, decreased protective antibody responses and increased autoimmune antibody responses. The effects of aging on the metabolic phenotype of B cells and on the metabolic programs that lead to the secretion of protective versus autoimmune antibodies are not known.

METHODS

Splenic B cells and the major splenic B cell subsets, Follicular (FO) and Age-associated B cells (ABCs), were isolated from the spleens of young and old mice and left unstimulated. The RNA was collected to measure the expression of markers associated with intrinsic inflammation and autoimmune antibody production by qPCR. B cells and B cell subsets were also stimulated with CpG and supernatants collected after 7 days to measure autoimmune IgG secretion by ELISA. Metabolic measures (oxygen consumption rate, extracellular acidification rate and glucose uptake) were performed using a Seahorse XFp extracellular flux analyzer.

RESULTS

Results have identified the subset of ABCs, whose frequencies and numbers increase with age and represent the most pro-inflammatory B cell subset, as the cell type mainly if not exclusively responsible for the expression of inflammatory markers and for the secretion of autoimmune antibodies in the spleen of old mice. Hyper-inflammatory ABCs from old mice are also hyper-metabolic, as compared to those from young mice and to the subset of FO B cells, a feature needed not only to support their higher expression of RNA for inflammatory markers but also their higher autoimmune antibody secretion.

CONCLUSIONS

These results identify a relationship between intrinsic inflammation, metabolism and autoimmune B cells and suggest possible ways to understand cellular mechanisms that lead to the generation of pathogenic B cells, that are hyper-inflammatory and hyper-metabolic, and secrete IgG antibodies with autoimmune specificities.

Phenotypic and Functional Characterization of Double Negative B Cells in the Blood of Individuals With Obesity

We have previously shown that obesity is associated with increased secretion of IgG antibodies with anti-self-reactivity. In this paper, we confirm and extend our previous findings. We show that the plasma of individuals with obesity is enriched in autoimmune antibodies whose levels are positively associated with blood frequencies of the subset of Double Negative (DN) B cells, which is the most pro-inflammatory B cell subset. We also show that DN B cells, significantly increased in the blood of obese versus lean individuals, are characterized by higher expression of immune activation markers and of the transcription factor T-bet, both associated with autoimmunity. The removal of DN B cells from the peripheral B cell pool significantly decreases in vitro secretion of anti-self IgG antibodies. These results altogether confirm the crucial role of DN B cells in the secretion of anti-self IgG antibodies in individuals with obesity.

Abstract PS11-20: Radiation therapy (RT) induced toxicity in advanced breast cancer (ABC) patients treated with CDK4/6 inhibitors (CDK4/6is)

Background: For patients with ABC being treated with CDK4/6is palliative (RT may still be necessary to metastatic sites that are symptomatic or at risk for complications. Although preclinical data suggests synergy between CDK4/6is and RT, clinical data regarding the safety of this combination are conflicting, with some reports of increased toxicity in the radiation field. Our aim was to review the practice regarding holding CDK4/6is during RT and subsequent clinical outcomes at the cancer centre with the largest volume of ABC patients in Canada. Methods: Chart review was completed for 313 ER positive and Her2 ABC pts treated with CDK4/6is at the Sunnybrook Health Sciences Centre from 2016 to 2020. All patients who received RT during the course of treatment with CDK4/6is were included in this analysis. Greater than expected toxicity events were defined as higher than grade 1 non-hematological toxicity as per Common Terminology Criteria for Adverse Events during RT or in the 30 days post RT. Descriptive statistics were used for demographics and treatment outcomes. Results: Fifty patients received RT to 74 different sites during treatment with CDK4/6is (46 palbociclib and 4 ribociclib). Median age was 56 (41-88) years. Most frequent RT sites were: bone (n=51), brain (n=7), lung (n=4), breast (n=4) and liver (n=3). CDK4/6is were held during RT of 55 sites (37 patients), starting a median of 7 (0-43) days prior to first fraction of RT and restarted a median of 7 (0-71) days after completing the RT. A CDK4/6i was administered concomitantly with RT to 19 sites (15 patients). No greater than expected toxicity was observed in patients for whom the CDK4/6i was held during RT. Among patients who received concomitant treatment, we observed 4 non-hematological adverse events (21%) in organs included in the field of radiation. In combination with palbociclib we observed grade 3 colitis after 30 Gy to hip/pelvis bones, grade 2 esophagitis after 30 Gy to C1-C4 vertebrae and grade 2 enteritis after 30 Gy to the upper femur. In combination with ribociclib one patient developed grade 3 hepatitis after 20Gy to T10-L2 vertebrae. Conclusions: This retrospective observational study of 50 patients with advanced ER positive Her2 negative BC treated with CDK4/6is who received palliative RT demonstrated a high rate of radiation toxicity (21%) in those patients for whom the CDK4/6i was given concurrently. Quality improvement work in this area, including practice guidelines, is warranted.

Citation Format: Neda Stjepanovic, Alia Thawer, Dilshad Nathoo, Danilo Giffoni, Maria Romero, Anthony Lott, Andrea Eisen, Rossanna Pezo, Katarzyna Jerzak, Maureen Trudeau, Sonal Gandhi, Ellen Warner. Radiation therapy (RT) induced toxicity in advanced breast cancer (ABC) patients treated with CDK4/6 inhibitors (CDK4/6is) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS11-20.

Abstract PS10-33: Analysis of factors associated with pathological complete response (pCR) in patients with HER2+ breast cancer receiving neoadjuvant chemotherapy

Background: Pathologic complete response (pCR) following neoadjuvant chemotherapy (NAC) is associated with improved survival outcomes among women with HER2 positive (HER2+) breast cancer. We aimed to analyze the clinical, pathological and molecular factors associated with pCR in our series of HER2+ breast cancer patients. Methods: Between 2009 and 2019, breast cancer patients receiving NAC at our centre were enrolled in a prospective database. For this study we selected women with HER2+ unilateral breast cancer stages II or III who received anthracycline-taxane NAC regimens (with trastuzumab given concurrently with the taxane) and subsequently underwent breast and axillary surgery with curative intent. Medical charts of these 161 women were retrospectively reviewed to determine what clinical, pathological and molecular characteristics were associated with pCR using bivariate and multivariate analysis. Results: Of the 161 HER2+ women median age at diagnosis was 49 years (range 25-78) with 90 (56%) women under age 50. Total of 104 (65%) tumors were stage II, 108 (67%) expressed estrogen and/or progesterone receptors, 139 (86%) had HER2 3+ expression by immunohistochemistry (IHC) and 22 (14%) had HER2 IHC 2+ expression with amplified HER2 on fluorescence in situ hybridization (FISH) test. The NAC regimens were: Doxorubicin-Cyclophosphamide-Paclitaxel for 83 (52%) and Fluorouracil-Epirubicin-Cyclophosphamide-Docetaxel for 78 (48%) women. A total of 73 patients [45%; 44/108 HR+ (41%) and 29/53 HR- (55%)] achieved pCR (p=0.94). pCR rate among HER2 IHC 3+ tumors was 69/139 (50%), while for HER2 IHC 2+ tumors was 4/22 (18%). On bivariate analysis HER2 IHC 3+, absence of estrogen receptors and absence of progesterone receptors were predictive of pCR, while age, menopausal status, histologic subtype, tumor grade and NAC regimen were not. In the multivariate model only HER2 IHC 3+ expression remained a significant predictor of pCR (OR =4.443, 95% CI 1.376 - 14.344). Conclusion: Our analysis suggests that for HER2+ breast cancers treated with NAC with anthracycline-taxane and trastuzumab, HER2 IHC 3+ expression is associated with a higher rate of pCR compared to HER2 IHC 2+ expression with FISH amplification. Further analysis in a larger cohort is warranted.

Citation Format: Neda Stjepanovic, Katarzyna Jerzak, Maureen Trudeau, Andrea Eisen, Sonal Gandhi, Ellen Warner, Danilo Giffoni MM Mata, Anthony Lott, Maria Romero, Sharon Lemon-Wong, Althea VanMassop, Xingshan Cao, William Tran, Rossanna Pezo. Analysis of factors associated with pathological complete response (pCR) in patients with HER2+ breast cancer receiving neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS10-33.

B Cells with a Senescent-Associated Secretory Phenotype Accumulate in the Adipose Tissue of Individuals with Obesity

Senescent cells accumulate in the adipose tissue (AT) of individuals with obesity and secrete multiple factors that constitute the senescence-associated secretory phenotype (SASP). This paper aimed at the identification of B cells with a SASP phenotype in the AT, as compared to the peripheral blood, of individuals with obesity. Our results show increased expression of SASP markers in AT versus blood B cells, a phenotype associated with a hyper-metabolic profile necessary to support the increased immune activation of AT-derived B cells as compared to blood-derived B cells. This hyper-metabolic profile is needed for the secretion of the pro-inflammatory mediators (cytokines, chemokines, micro-RNAs) that fuel local and systemic inflammation.

Histopathologic analysis of extracted thrombi from deep venous thrombosis and pulmonary embolism: Mechanisms and timing

BACKGROUND

Mechanical thrombectomy is increasingly being used as an alternative to pharmacologic therapies for the treatment of patients with acute deep venous thrombosis (DVT) and pulmonary embolism (PE) and allows direct histopathologic comparison of thrombi extracted from living patients. We performed histopathologic analysis to thrombi extracted from cases of DVT and PE to gain insights into their relative cellular compositions.

METHODS

Thrombus retrieved using a catheter-based thrombectomy system (ClotTriever for lower extremity DVT and FlowTriever for PE) from the 17 patients (7 DVT cases and 10 PE cases) were histologically evaluated. Histological features were used to estimate their age and pathological characteristics.

RESULTS

The thrombus in all cases were composed of fibrin, platelets, red blood cells, and acute inflammatory cells. The weights of thrombus obtained from DVT versus PE cases were heavier (DVT 7.2 g (g) (5.6-10.2) vs. PE 4.8 g (3.6-6.8), p = .01). Overall thrombus healing (i.e., thrombus composed of smooth muscle cells, endothelial cells, and proteoglycans) was different between DVT and PE cases. 6/7 (86%) with features of late stage healing were from DVT cases while only three of ten (30%) were from PE cases while PE contained more acute thrombi with 7/10 (70%) stage 2 as compared 1/7 (14%) for DVT (p = .0498).

CONCLUSION

This study is the first to directly compare the histology of extracted thrombus in DVT versus PE cases from patients with clinical events. Overall PE cases demonstrated significantly earlier stage thrombus with a larger component of red blood cells.

Pathological Evidence for SARS-CoV-2 as a Cause of Myocarditis: JACC Review Topic of the Week

To investigate whether severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2)–induced myocarditis constitutes an important mechanism of cardiac injury, a review was conducted of the published data and the authors’ experience was added from autopsy examination of 16 patients dying of SARS-CoV-2 infection. Myocarditis is an uncommon pathologic diagnosis occurring in 4.5% of highly selected cases undergoing autopsy or endomyocardial biopsy. Although polymerase chain reaction–detectable virus could be found in the lungs of most coronavirus disease-2019 (COVID-19)–infected subjects in our own autopsy registry, in only 2 cases was the virus detected in the heart. It should be appreciated that myocardial inflammation alone by macrophages and T cells can be seen in noninfectious deaths and COVID-19 cases, but the extent of each is different, and in neither case do such findings represent clinically relevant myocarditis. Given its extremely low frequency and unclear therapeutic implications, the authors do not advocate use of endomyocardial biopsy to diagnose myocarditis in the setting of COVID-19.

Microthrombi as a Major Cause of Cardiac Injury in COVID-19: A Pathologic Study

BACKGROUND

Cardiac injury is common in patients who are hospitalized with coronavirus disease 2019 (COVID-19) and portends poorer prognosis. However, the mechanism and the type of myocardial damage associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remain uncertain.

METHODS

We conducted a systematic pathological analysis of 40 hearts from hospitalized patients dying of COVID-19 in Bergamo, Italy, to determine the pathological mechanisms of cardiac injury. We divided the hearts according to presence or absence of acute myocyte necrosis and then determined the underlying mechanisms of cardiac injury.

RESULTS

Of the 40 hearts examined, 14 (35%) had evidence of myocyte necrosis, predominantly of the left ventricle. Compared with subjects without necrosis, subjects with necrosis tended to be female, have chronic kidney disease, and have shorter symptom onset to admission. The incidence of severe coronary artery disease (ie, >75% cross-sectional narrowing) was not significantly different between those with and without necrosis. Three of 14 (21.4%) subjects with myocyte necrosis showed evidence of acute myocardial infarction, defined as ≥1 cm² area of necrosis, whereas 11 of 14 (78.6%) showed evidence of focal (>20 necrotic myocytes with an area of ≥0.05 mm² but <1 cm²) myocyte necrosis. Cardiac thrombi were present in 11 of 14 (78.6%) cases with necrosis, with 2 of 14 (14.2%) having epicardial coronary artery thrombi, whereas 9 of 14 (64.3%) had microthrombi in myocardial capillaries, arterioles, and small muscular arteries. We compared cardiac microthrombi from COVID-19-positive autopsy cases to intramyocardial thromboemboli from COVID-19 cases as well as to aspirated thrombi obtained during primary percutaneous coronary intervention from uninfected and COVID-19-infected patients presenting with ST-segment-elevation myocardial infarction. Microthrombi had significantly greater fibrin and terminal complement C5b-9 immunostaining compared with intramyocardial thromboemboli from COVID-19-negative subjects and with aspirated thrombi. There were no significant differences between the constituents of thrombi aspirated from COVID-19-positive and -negative patients with ST-segment-elevation myocardial infarction.

CONCLUSIONS

The most common pathological cause of myocyte necrosis was microthrombi. Microthrombi were different in composition from intramyocardial thromboemboli from COVID-19-negative subjects and from coronary thrombi retrieved from COVID-19-positive and -negative patients with ST-segment-elevation myocardial infarction. Tailored antithrombotic strategies may be useful to counteract the cardiac effects of COVID-19 infection.

Effects of obesity on serum levels of SARS-CoV-2-specific antibodies in COVID-19 patients

SARS-CoV-2 (Severe Acute Respiratory Syndrome Corona Virus-2), cause of COVID-19 (Coronavirus Disease of 2019), represents a significant risk to people living with pre-existing conditions associated with exacerbated inflammatory responses and consequent dysfunctional immunity. In this paper, we have evaluated the effects of obesity, a condition associated with chronic systemic inflammation, on the secretion of SARS-CoV-2-specific IgG antibodies in the blood of COVID-19 patients. Results have shown that SARS-CoV-2 IgG antibodies are negatively associated with Body Mass Index (BMI) in COVID-19 obese patients, as expected based on the known effects of obesity on humoral immunity. Antibodies in COVID-19 obese patients are also negatively associated with serum levels of pro-inflammatory and metabolic markers of inflammaging and pulmonary inflammation, such as SAA (serum amyloid A protein), CRP (C-reactive protein) and ferritin, but positively associated with NEFA (nonesterified fatty acids). These results altogether could help to identify an inflammatory signature with strong predictive value for immune dysfunction that could be targeted to improve humoral immunity in individuals with obesity as well as with other chronic inflammatory conditions.

Comprehensive Assessment of Human Accessory Renal Artery Periarterial Renal Sympathetic Nerve Distribution

OBJECTIVES

The aim of this study was to understand the anatomy of periarterial nerve distribution in human accessory renal arteries (ARAs).

BACKGROUND

Renal denervation is a promising technique for blood pressure control. Despite the high prevalence of ARAs, the anatomic distribution of periarterial nerves around ARAs remains unknown.

METHODS

Kidneys with surrounding tissues were collected from human autopsy subjects, and histological evaluation was performed using morphometric software. An ARA was defined as an artery arising from the aorta above or below the dominant renal artery (DRA) or an artery that bifurcated within 20 mm of the takeoff of the DRA from the aorta. The DRA was defined as an artery that perfused >50% of the kidney.

RESULTS

A total of 7,287 nerves from 14 ARAs and 9 DRAs were evaluated. The number of nerves was smaller in the ARA than DRA (median: 30 [interquartile range: 17.5 to 48.5] vs. 49 [interquartile range: 36 to 76]; p < 0.0001). In both ARAs and DRAs, the distance from the arterial lumen to nerve was shortest in the distal, followed by the middle and proximal segments. On the basis of the post-mortem angiography, ARAs were divided into large (≥3 mm diameter) and small (<3 mm) groups. The number of nerves was greatest in the DRA, followed by the large and small ARA groups (53 [41 to 97], 38 [25 to 53], and 24.5 [10.5 to 36.3], respectively; p = 0.001).

CONCLUSIONS

ARAs showed a smaller number of nerves than DRAs, but these results were dependent on the size of the ARA. Ablation, especially in large ARAs, may allow more complete denervation with the potential to further reduce blood pressure.

Clinical and microbiological characteristics of paracoccidioidomycosis in patients with AIDS in Buenos Aires, Argentina

Paracoccidioidomycosis (Pm) is a systemic disease, endemic in the American continent. There are two different clinical forms, the infant-juvenile or subacute form (PmS) and the chronic adult form (PmC). The human immunodeficiency virus (HIV) associated paracoccidioidomycosis (PmHIV) shares characteristics with both of the previously mentioned forms. The objective of this work was to describe the epidemiological, clinical and laboratory features of the PmHIV and to compare them with the ones of PmS and the PmC. A retrospective analysis of 119 patients with paracoccidioidomycosis was performed. Ninety four suffered the chronic form, 11 the subacute one and 14 were coinfected with HIV. Patients with PmHIV presented a CD4+ T lymphocytes median of 70.5 cells/μl, 71.4% had fever, 64.3% had a miliary pattern on the chest radiography, 64.3% had hepatosplenomegaly, 64.3% had mucosal lesions and 50% had skin lesions. One patient died during his hospitalization. The clinical presentation of Pm in patients with HIV resembled the subacute form with fever, hepatomegaly and skin lesions. However, they also tended to present mucosal lesions, positive serology for Pm and pulmonary parenchyma lesions as usually seen in PmC (9/14 PmHIV patients had overlapping features, while 4/14 PmHIV patients clinically resembled PmS and 1/14 PmC). The incidence of Pm has not changed with the burden of AIDS as it has happened with other fungal infections but it appears clinically different from the classic clinical forms of the disease.

Analysis of the smear layer generated by different activation systems: an in vitro study

OBJECTIVES

To evaluate via scanning electron microscopy the amount of smear layer generated during the use of sonic and ultrasonic activation systems with standardized short-term intentional contacts with the canal walls.

METHODOLOGY

Seventy single-root human teeth were randomly assigned to 2 control (n = 5 each): NC (negative control), PC (positive control) and four experimental groups (n = 15 each): NC (negative control), PC (positive control), G1 (passive ultrasonic irrigation with Irrisafe), G2 (ultrasonic irrigation with EndoUltra), G3 (sonic irrigation with Endoactivator), G4 (sonic irrigation with Eddy). Samples were instrumented with ProTaper Next®. An irrigation protocol with sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA) was followed for both PC and the experimental groups. Standardized intentional contacts were made in the mesial walls during 5 s at WL - 2 mm in all experimental groups. Two calibrated evaluators scored the smear layer generated with an ordinal scale by scanning electron microscopy. The weighted kappa coefficient (K_w) was calculated to determine the inter-observer agreement. Post-consensus ordinal data were analyzed using the ordinal (linear) chi-square test.

RESULTS

When the agitation file is in contact with dentine walls, Irrisafe® significantly generated the least amount of smear layer in the coronal third (p < 0.05). Both in the middle and apical third, activation with Irrisafe® also showed statistically significant better results than Eddy™ and EndoUltra®. Endoactivator® showed significant better results than EndoUltra® and Eddy™ in the apical third (p < 0.05).

CONCLUSIONS

Irrisafe generated the least amount of smear layer in the entire canal and similar to Endoactivator in the apical third when the agitation file is in contact with dentine walls.

CLINICAL RELEVANCE

The smear layer is generated during activation. It is common to apply irrigation protocols where after the removal of the smear layer using chelants, a final rinse and activation is carried out but there are no previous studies analyzing the possible creation of a new smear layer with this final activation.

AB0911 PREVALENCE AND RISK FACTORS OF HIP FRACTURE ASSOCIATED WITH OSTEOPOROSIS IN A GERIATRIC POPULATION FROM COLOMBIAN NORTH EAST

Background:

Hip fracture is a frequent cause of hospital admission in older adults.1The prevalence of hip fracture associated with osteoporosis in the elderly is 18% in women and 6% in men.2Likewise, the attention of this event requires an approximate value of 2,943 dollars, which represents an average of 18,95% of the per capita income of most countries.3It is also established that appropriate and timely treatment of osteoporosis can prevent the appearance of fractures.4

Objectives:

The aim of this study was to determine the prevalence of hip fracture associated with osteoporosis, as well as the associated factors to its presentation in a geriatric population in Colombia.

Methods:

Cross-sectional study that included 130 patients over 65 years old, who consulted the University Hospital of Santander with hip fracture. The main variable of exposition was the medical history of osteoporosis. Descriptive analysis was performed with absolute and relative frequency measurements for the qualitative variables and central tendency measures and dispersion according to the distribution of the variables. Subsequently, the bivariate logistic regression analysis was performed to identify the associated risk variables. The analysis was performed with the Stata 12.0 Software.

Results:

From the 130 patients included in the study, 33.85% corresponded to the male gender. The average age was 82.49 years with a DS of 8.35 years. The median length of hospital stay was 17.5 days with an interquartile range of 11 to 26 days. The most common comorbidity was hypertension in 65.38%, followed by diabetes and COPD in 21.54%, heart failure in 19.23% and chronic kidney disease in 17.69%. The median Charlson score was 5 with an interquartile range between 4 and 6 points. 13.85% of the patients admitted had concomitant osteoporosis, 77.7% of them were women and 8,46% of them had severe osteoporosis, with history of prior fracture, without treatment. In the bivariate analysis, an association was found between having COPD (OR: 4.89, 95% CI 1.71-13.95, p = 0.003), dementia (OR: 3.20, 95% CI 1.05-19.56, p = 0.044), malnutrition (OR: 3.42, IC95 % 1.10 - 10.60, p = 0.032), and osteoporosis associated with hip fracture at hospital admission. Likewise, a greater probability was found for the development of in-hospital pneumonia (OR: 2.48, 95% CI 1.14 - 7.98, p = 0.04) in patients with osteoporosis compared to those who did not have bone disease.

Conclusion:

13.85% of patients who entered due to hip fracture had osteoporosis as comorbidity, data comparable to that previously reported. Variables associated with the presence of osteoporosis at admission in patients with hip fracture were found like history of COPD, dementia, and malnutrition, which makes it likely that those patients with pathologies that decrease physical activity or food intake can impact in an important way the appearance of osteoporosis. One of the most important contributions of this study is the identification of in-hospital complication (pneumonia), which should be actively monitored in these patients.

References:

[1]Falaschi P (Paolo), Marsh DR. Orthogeriatrics. Springer; 2017.

[2]Cooper C, Campion G, Melton LJ. Hip fractures in the elderly: A world-wide projection. Osteoporos Int. 1992 Nov;2(6):285–9.

[3]Mohd-Tahir NA, Li SC. Economic burden of osteoporosis-related hip fracture in Asia: a systematic review. Vol. 28, Osteoporosis International. Springer London; 2017. p. 2035–44.

[4]Solimeo SL, Mccoy K, Reisinger HS, Adler RA, Sarrazin MV. Factors Associated With Osteoporosis Care of Men Hospitalized for Hip Fracture: A Retrospective Cohort Study. 2019;

Disclosure of Interests:

None declared

Advances in mammalian target of rapamycin kinase inhibitors: application to devices used in the treatment of coronary artery disease

Mammalian target of rapamycin (mTOR) inhibitors have been applied to vascular coronary devices to avoid neointimal growth and have become the predominant pharmacological agents used to prevent restenosis. mTOR inhibitors can affect not only proliferating vascular smooth muscle cells but also endothelial cells and therefore can result in delayed healing of the vessel including endothelialization. Emerging evidence suggests accelerated atherosclerosis due to the downstream negative effects on endothelial barrier functional recovery. The development of neoatherosclerosis within the neointima of drug-eluting stents can result in late thrombotic events. This type of problematic healing response may open the way for specific mTOR kinase inhibitors, such as ATP-competitive mTOR inhibitors. These inhibitors demonstrate a better healing profile than traditional limus-based drug-eluting stent and their clinical efficacy remains unknown.

Identification and characterization of adipose tissue-derived human antibodies with “anti-self” specificity

We have previously shown that the human obese adipose tissue (AT) contributes to increased secretion of adipocyte-specific IgG antibodies in individuals with obesity. We have also shown that this occurs without any exogenous stimulation, because the ongoing process of cell death in the obese AT leads to the release of “self” antigens able to induce chronic stimulation of B cells. Here, we confirm and extend our initial observation on a different cohort of individuals, and we show that also the plasma of obese individuals is enriched in IgG antibodies with specificities for adipocyte-derived antigens. Adipocyte-specific IgG secreted in the obese AT are significantly correlated with those present in plasma. Using immunoprecipitation and mass spectrometry, we have identified these antigenic specificities. The antigens are almost exclusively intracellular or cell-associated, usually not “self” antigens, but they are released by cells dying in the AT. These antigens will be used in protein arrays to screen plasma from individuals with obesity and also with autoimmune diseases. We have indeed preliminary evidence that the plasma of Rheumatoid Arthritis patients is enriched in adipocyte-specific IgG antibodies, suggesting that obesity may contribute to pathogenicity in autoimmune patients. Finally, we show for the first time that not only macrophages but also adipocytes in the obese AT are efficient antigen-presenting cells and stimulate the secretion of IgG autoimmune antibodies. They do so because they express the antigen-presenting molecules CD1d and, to a lesser extent, MHC class II, as well as the co-stimulatory molecule CD86. These results may lead to the development of novel therapeutic strategies to controlautoimmunity.