Observation of Seven Astrophysical Tau Neutrino Candidates with IceCube

We report on a measurement of astrophysical tau neutrinos with 9.7 yr of IceCube data. Using convolutional neural networks trained on images derived from simulated events, seven candidate ν_{τ} events were found with visible energies ranging from roughly 20 TeV to 1 PeV and a median expected parent ν_{τ} energy of about 200 TeV. Considering backgrounds from astrophysical and atmospheric neutrinos, and muons from π^{±}/K^{±} decays in atmospheric air showers, we obtain a total estimated background of about 0.5 events, dominated by non-ν_{τ} astrophysical neutrinos. Thus, we rule out the absence of astrophysical ν_{τ} at the 5σ level. The measured astrophysical ν_{τ} flux is consistent with expectations based on previously published IceCube astrophysical neutrino flux measurements and neutrino oscillations.

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.

Observation of high-energy neutrinos from the Galactic plane

The origin of high-energy cosmic rays, atomic nuclei that continuously impact Earth's atmosphere, is unknown. Because of deflection by interstellar magnetic fields, cosmic rays produced within the Milky Way arrive at Earth from random directions. However, cosmic rays interact with matter near their sources and during propagation, which produces high-energy neutrinos. We searched for neutrino emission using machine learning techniques applied to 10 years of data from the IceCube Neutrino Observatory. By comparing diffuse emission models to a background-only hypothesis, we identified neutrino emission from the Galactic plane at the 4.5σ level of significance. The signal is consistent with diffuse emission of neutrinos from the Milky Way but could also arise from a population of unresolved point sources.

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.

MiniBooNE and MicroBooNE Combined Fit to a 3+1 Sterile Neutrino Scenario

This Letter presents the results from the MiniBooNE experiment within a full "3+1" scenario where one sterile neutrino is introduced to the three-active-neutrino picture. In addition to electron-neutrino appearance at short baselines, this scenario also allows for disappearance of the muon-neutrino and electron-neutrino fluxes in the Booster Neutrino Beam, which is shared by the MicroBooNE experiment. We present the 3+1 fit to the MiniBooNE electron-(anti)neutrino and muon-(anti)neutrino data alone and in combination with MicroBooNE electron-neutrino data. The best-fit parameters of the combined fit with the exclusive charged-current quasielastic analysis (inclusive analysis) are Δm^{2}=0.209  eV^{2}(0.033  eV^{2}), |U_{e4}|^{2}=0.016(0.500), |U_{μ4}|^{2}=0.500(0.500), and sin^{2}(2θ_{μe})=0.0316(1.0). Comparing the no-oscillation scenario to the 3+1 model, the data prefer the 3+1 model with a Δχ^{2}/d.o.f.=24.7/3(17.3/3), a 4.3σ(3.4σ) preference assuming the asymptotic approximation given by Wilks's theorem.

Evidence for neutrino emission from the nearby active galaxy NGC 1068

A supermassive black hole, obscured by cosmic dust, powers the nearby active galaxy NGC 1068. Neutrinos, which rarely interact with matter, could provide information on the galaxy’s active core. We searched for neutrino emission from astrophysical objects using data recorded with the IceCube neutrino detector between 2011 and 2020. The positions of 110 known gamma-ray sources were individually searched for neutrino detections above atmospheric and cosmic backgrounds. We found that NGC 1068 has an excess of 79 − 20 + 22 neutrinos at tera–electron volt energies, with a global significance of 4.2σ, which we interpret as associated with the active galaxy. The flux of high-energy neutrinos that we measured from NGC 1068 is more than an order of magnitude higher than the upper limit on emissions of tera–electron volt gamma rays from this source.

Review of direct impact health indicators of COVID-19 in the scientific literature published between January 2020 and June 2021

Background

The Joint Action Population Health Information Research Infrastructure (PHIRI) seeks to create infrastructures to generate quality data on the COVID-19 pandemic between European countries. The aim of this study is to present a synthesis of health indicators used to evaluate the direct impact of COVID-19

Methods

Scoping review using a common search strategy in Pubmed, Embase and WHO Covid-19 databases. Health indicators of direct impact of COVID-19 were obtained from observational studies in the general population, hospitals and long-term care facilities from papers published worldwide in English between 01/01/2020 and 06/31/2021. Titles and abstracts were screened first by 15 reviewers using the Rayyan tool. Any discrepancies were solved by agreement between reviewers. Then, articles containing indicators of direct impact were selected in a full-text reading phase. Of them, a random sample of 35 was drawn and their indicators were described.

Results

After eliminating 262 duplicates 3891 records were reviewed. Screening discarded 3171 abstracts. Of 720 articles sought for retrieval, 445 met inclusion criteria for indicators extraction. In a sample of 35 papers (8.1%), 116 direct impact indicators of COVID-19 were identified. 28 morbidity indicators were found, classified as indicators of prevalence (n = 15), incidence (6), transmissibility (4) and underreported infection (4); 32 of mortality (mortality rate, 9; case fatality rate, 17; time to death, 2); and 54 for severity (complications, 27; mechanical ventilation, 12; hospitalization, 8; requiring ICU admission, 1; time from hospitalization to ICU admission, 1). Two composite indicators of severity and mortality were also identified.

Conclusions

According to the scientific literature, a wide variety of health indicators has been used to measure the direct impact of COVID-19. The systematization of indicators used in the current COVID-19 pandemic could help for future health crises management.

Search for Unstable Sterile Neutrinos with the IceCube Neutrino Observatory

We present a search for an unstable sterile neutrino by looking for a resonant signal in eight years of atmospheric ν_{μ} data collected from 2011 to 2019 at the IceCube Neutrino Observatory. Both the (stable) three-neutrino and the 3+1 sterile neutrino models are disfavored relative to the unstable sterile neutrino model, though with p values of 2.8% and 0.81%, respectively, we do not observe evidence for 3+1 neutrinos with neutrino decay. The best-fit parameters for the sterile neutrino with decay model from this study are Δm_{41}^{2}=6.7_{-2.5}^{+3.9}  eV^{2}, sin^{2}2θ_{24}=0.33_{-0.17}^{+0.20}, and g^{2}=2.5π±1.5π, where g is the decay-mediating coupling. The preferred regions of the 3+1+decay model from short-baseline oscillation searches are excluded at 90% C.L.

JS04.6.A The landscape of tumor cell states and spatial organization in H3-K27M mutant diffuse midline glioma across age and location

Background

Histone 3 lysine27-to-methionine mutations (H3-K27M) frequently occur in childhood diffuse midline gliomas (DMGs) of the pons, thalamus and spinal cord, presumed to be driven by the specific spatiotemporal context of these midline locations during postnatal development. While most common in the pons and at mid-childhood ages, the same oncohistone mutation is recurrently detected in adult DMGs and throughout different midline regions. The potential heterogeneity of tumors at different ages and in different anatomical locations of the midline are vastly understudied.

Material and Methods

Through dissecting the transcriptomic, epigenomic and spatial architectures of a comprehensive cohort of patient H3-K27M DMGs - spanning the age range from 2-68 years and locations from spinal cord to thalamus - at single cell resolution, we delineate how age- and location-dependent contexts shape glioma cell-intrinsic and -extrinsic features in light of the shared driver mutation.

Results

We identify that oligodendrocyte precursor (OPC)-like cells constitute the stem-like compartment in H3-K27M DMGs across all clinico-anatomical groups, however, depending on location, display varying levels of maturity resembling less differentiated pre-OPCs or more mature OPCs further differentiated along the oligodendroglial lineage. We further demonstrate increased mesenchymal cell states in adult tumors, which we link to age-related differences in glioma-associated immune cell compartments. We for the first time resolve the spatial organization of H3-K27M DMG cell types in intact patient tissues, identifying a local niche of the oligodendroglial lineage.

Conclusion

Our study provides a powerful resource for rational modeling and therapeutic frameworks taking into account determinants of age and location in this lethal glioma group.

Relationships Between Serum Cortisol, RAGE-Associated s100A8/A9 Levels, and Self-Reported Cancer-Related Distress in Women With Nonmetastatic Breast Cancer

OBJECTIVE

Elevated inflammation and psychological distress in patients with breast cancer (BCa) have been related to poorer health outcomes. Regulation of the hypothalamic-pituitary-adrenal axis and signaling of the receptor for advanced glycation end products (RAGE) are important in the inflammatory response and have been associated with increased stress and poorer health outcomes in patients with cancer. This study examined relationships among circulating cortisol, a measure of hypothalamic-pituitary-adrenal axis activity and physiological stress; s100A8/A9, a RAGE ligand and emerging cancer-related biological measure; and self-reported cancer-related distress.

METHODS

Patients with BCa ( N = 183, stages 0-IIIb) were recruited 2 to 10 weeks after surgery but before receiving adjuvant therapies. Participants provided blood samples, from which serum cortisol and s100A8/A9 levels were determined, and completed a psychosocial questionnaire. Regression analyses, adjusting for age, cancer stage, time since surgery, race, and menopausal status, were conducted examining the relationships between cortisol, s100A8/A9, and cancer-related distress (Impact of Event Scale [IES]-Revised).

RESULTS

Cortisol and s100A8/A9 levels were positively related ( β = 0.218, t (112) = 2.332, p = .021), although the overall model was not significant. Cortisol levels were also positively associated with IES-Intrusions ( β = 0.192, t (163) = 2.659, p = .009) and IES-Hyperarousal subscale scores ( β = 0.171, t (163) = 2.304, p = .022).

CONCLUSIONS

Patients with higher cortisol levels also reported higher s100A8/A9 levels and more cancer-related distress. The relationship between cortisol and s100A8/A9 supports a link between the stress response and proinflammatory physiological processes known to predict a greater metastatic risk in BCa. Stress processes implicated in cancer biology are complex, and replication and extension of these initial findings are important.

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.

First Leptophobic Dark Matter Search from the Coherent-CAPTAIN-Mills Liquid Argon Detector

We report the first results of a search for leptophobic dark matter (DM) from the Coherent-CAPTAIN-Mills (CCM) liquid argon (LAr) detector. An engineering run with 120 photomultiplier tubes (PMTs) and 17.9×10^{20} protons on target (POT) was performed in fall 2019 to study the characteristics of the CCM detector. The operation of this 10-ton detector was strictly light based with a threshold of 50 keV and used coherent elastic scattering off argon nuclei to detect DM. Despite only 1.5 months of accumulated luminosity, contaminated LAr, and nonoptimized shielding, CCM's first engineering run has already achieved sensitivity to previously unexplored parameter space of light dark matter models with a baryonic vector portal. With an expected background of 115 005 events, we observe 115 005+16.5 events which is compatible with background expectations. For a benchmark mediator-to-DM mass ratio of m_{V_{B}}/m_{χ}=2.1, DM masses within the range 9  MeV≲m_{χ}≲50  MeV are excluded at 90% C. L. in the leptophobic model after applying the Feldman-Cousins test statistic. CCM's upgraded run with 200 PMTs, filtered LAr, improved shielding, and 10 times more POT will be able to exclude the remaining thermal relic density parameter space of this model, as well as probe new parameter space of other leptophobic DM models.

Strong Constraints on Neutrino Nonstandard Interactions from TeV-Scale ν_{μ} Disappearance at IceCube

We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter ε_{μτ}. The best-fit value is consistent with no NSI at a p value of 25.2%. With a 90% confidence interval of -0.0041≤ε_{μτ}≤0.0031 along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.

Temporal and spatial dynamics in the regulation of myocardial metabolism during the ischemia-reperfusion process

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was supported by “Instituto de Salud Carlos III” and “Fondos Europeos de Desarrollo Regional FEDER” (grant numbers PI20/00637 and CIBERCV16/11/00486) and Conselleria de Educación – Generalitat Valenciana (PROMETEO/2021/008).

Introduction

In the context of severe myocardial ischemia, cardiac metabolism shifts from beta oxidation to glycolisis. However, the temporal and spatial dynamics of the main regulators of myocardial metabolism during the ischemia-reperfusion process in the infarcted heart has not been fully characterized.

Methods

Myocardial infarction (MI) was induced in swine by means of 90 minutes occlusion of the mid left anterior descending coronary artery using angioplasty balloons. Tetrazolium staining and intracoronary infusion of thioflavin-S were used to define the infarcted, adjacent, and remote areas. mRNA and protein expression of PGC1a, PPARa, ERRa, GLUT1, and GLUT4 were quantified in controls and in MI groups submitted to 48 hours and 3 weeks of reperfusion.

Results

Compared to controls, a severe and generalized drop of PGC1a mRNA gene and protein levels occurred in the infarcted, adjacent and remote areas since ischemia onset until 48 hours reperfusion that persists at 1 month in the infarcted region. Similar dynamics occurred in the infarcted, adjacent, and remote areas in the case of PPARa gene expresion; PPARa protein significantly decreased only until 48 hours reperfusion in the infarcted area. ERRa gene and protein expression persistenly decreased only in the infarcted region since ischemia onset until 1 month. Incrases in GLUT1 (since ischemia onset) and GLUT4 (at 1 month) were detected.

Conclusions

Dynamics and generalized changes in metabolism regulation to a shift from beta oxidation to glycolisis occur in the infarcted heart since ischemia onset until late after reperfusion. Further research in this field can be helpful for a better understanding of pathophysiology of myocardial infarction and to explore new therapeutic options.

Collagen bundle orientation by Fourier analysis in myocardial infarction scarring

Funding Acknowledgements

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): “Instituto de Salud Carlos III” and “Fondos Europeos de Desarrollo Regional FEDER” and Conselleria de Educación – Generalitat Valenciana.

Introduction

After acute myocardial infarction (AMI), the lack of oxygen and nutrients leads to cardiomyocyte necrosis and eventually to the formation of a collagen-based scar. Infarct scar characteristics, such as collagen bundle orientation, have a relevant influence on scar mechanics, the occurrence of cardiac arrhythmias, left ventricular dilation or aneurysm formation, wall stiffness, and the development of wall rupture or heart failure. However, the most adequate method for collagen bundle orientation (CBO) measurement in myocardial scar is not established.

Purpose

We aim to compare the measurement of collagen bundle orientation in infarct scar by Fourier analysis in three different histopathological techniques.

Methods

Juvenile swine (n=21) were subjected, by means of percutaneous balloon inflation, to a transient 90-min occlusion of mid left anterior descending artery followed by one month of reperfusion (chronic AMI group). Samples were obtained from the infarcted zone and stained with Masson’s trichrome, Picrosirius red and Haematoxylin-Eosin (H-E) standard protocols. Five microphotographs of the myocardial scar were taken at 200x magnification with light, polarised and confocal microscopy, respectively. A single observer measured CBO by means of Fast Fourier Transform analysis using a semi-automated protocol. Comparability between techniques was studied by the Intraclass Correlation Coefficient (ICC), the coefficient of variation (CV) and the Bland-Altman (B&A) plots and limits of agreement.

Results

Measurement of CBO in Masson’s trichrome tended to show higher (more "random-oriented") values than in Picrosirius and H-E+confocal techniques (ICC 0.79 and 0.7, p=0.001 and 0.005; B&A 0.29 to -0.02 and 0.43 to 0.01; CV 6.97% and 12.98%, respectively). However, measurement of CBO in Picrosirius and H-E+confocal techniques showed an "almost perfect" agreement (ICC 0.84, p<0.001; B&A 0.28 to -0.09; CV 17.33%). Selective staining and/or visualization of collagen in these latter techniques may underlie our findings, contrary to non-selective Masson’s trichrome.

Conclusion

Picrosirius red staining (visualized with polarised microscopy) and Haematoxylin-Eosin (visualized with confocal microscopy) are comparable in terms of collagen bundle orientation measurement by Fourier analysis in an animal model of chronic infarct scar. Masson’s trichrome (visualized with light microscopy) tends to show more "random-oriented" values, potentially due to non-specific staining and visualization of non-collagenous structures such as cells, and should not be recommended for this specific purpose.

Brief Post-Surgical Stress Management Reduces Pro-Inflammatory Cytokines in Overweight and Obese Breast Cancer Patients Undergoing Primary Treatment

Background:

Overweight and obese (OW/OB) body mass index (BMI) is associated with greater inflammation and poorer outcomes in breast cancer (BC). Stress management interventions using cognitive behavioral therapy (CBT) and relaxation training (RT) have reduced inflammation in BC patients but have not been tested specifically in OW/OB patients undergoing primary treatment. We developed brief CBT and RT-based group interventions and tested their effects (vs time-matched Health Education [HE] control) on serum inflammatory cytokines (IL-6, IL-1β and TNF-α) in OW/OB vs normal weight (NW) BC patients during primary treatment. We hypothesized OW/OB women would show higher levels of inflammatory cytokines, and that stress management would decrease these cytokines more in OW/OB women than in NW women.

Methods:

Stage 0 – III BC patients were enrolled post-surgery and before initiating adjuvant therapy, were randomized to either 5 weeks of CBT, RT, or HE, and provided questionnaires and blood samples at baseline and 6-months. Serum cytokine levels were measured by ELISA. Repeated measures analysis of variance tested the interaction of condition by BMI by time in predicting cytokine levels over 6 months, controlling for age, stage, ethnicity, and income.

Results:

The sample (N = 153) majority was OW/OB (55.6%). We found differences in baseline IL-6 and IL-1β across BMI categories, with greater IL-6 (p < 0.005) and IL-1β (p < 0.04) in OW and OB vs NW women, but no difference between OW and OB women. There were no differences in baseline TNF-α among BMI groups. BMI category moderated the effect of brief stress management interventions on IL-6 changes over 6-months (p = 0.028): CBT/RT vs HE decreased IL-6 in OW/OB (p = 0.045) but not in NW patients (p = 0.664). There were no effects on IL-1β or TNF-α. Results could not be explained by differences in receipt of adjuvant therapy, prescription medications, or changes in physical activity.

Conclusions:

OW/OB women with newly diagnosed BC had significantly greater serum IL-6 and IL-1β than NW women post-surgery. Brief stress management delivered with primary treatment among OW/OB patients may reduce the increases in inflammatory markers known to accompany adjuvant treatments and could thus promote better outcomes.

Clinical Trial Registration:

NCT02103387.

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)

Search for Relativistic Magnetic Monopoles with Eight Years of IceCube Data

We present an all-sky 90% confidence level upper limit on the cosmic flux of relativistic magnetic monopoles using 2886 days of IceCube data. The analysis was optimized for monopole speeds between 0.750c and 0.995c, without any explicit restriction on the monopole mass. We constrain the flux of relativistic cosmic magnetic monopoles to a level below 2.0×10^{-19}  cm^{-2} s^{-1} sr^{-1} over the majority of the targeted speed range. This result constitutes the most strict upper limit to date for magnetic monopoles with β≳0.8 and up to β∼0.995 and fills the gap between existing limits on the cosmic flux of nonrelativistic and ultrarelativistic magnetic monopoles.

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.

An exploration of the sociodemographic and health conditions associated with self-rated wellbeing for Aboriginal and Torres Strait Islander adults

Objective

To identify sociodemographic factors and health conditions associated with self-rated wellbeing for Aboriginal and Torres Strait Islander adults. Participants were recruited via investigator networks and an online panel provider with an established nationwide panel of Aboriginal and Torres Strait Islander adults. Those interested were invited to complete a survey that included an assessment of wellbeing using a visual analogue scale. Data was collected from October–November 2019 and August–September 2020. Exploratory analyses were conducted to ascertain factors associated with self-rated wellbeing for Aboriginal and Torres Strait Islander adults.

Results

Having more than enough money to last until next pay day, full-time employment, completion of grade 12, having a partner, and living with others were significantly associated with higher wellbeing among Aboriginal and Torres Strait Islander adults. A self-reported history of depression, anxiety, other mental health conditions, heart disease, or disability were associated with lower self-rated wellbeing scores. Our findings indicate a need for further investigation among these socioeconomic and patient groups to identify how to improve and support the wellbeing of Aboriginal and Torres Strait Islander adults.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13104-021-05794-3.

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.

Impact of switching to raltegravir and/or adding losartan in lymphoid tissue fibrosis and inflammation in people living with HIV. A randomized clinical trial

BACKGROUND

Persistent inflammation and immune activation are associated with lymph node fibrosis and end-organ diseases in treatment-suppressed people living with HIV (PLWH). We investigated the effect of switching to raltegravir and/or adding losartan on lymphoid tissue fibrosis and on the inflammatory/immune-activation mediators in treated HIV patients.

METHODS

Chronic HIV-infected patients treated with two nucleoside reverse transcriptase inhibitors (2NRTI) and one non-NRTI (NNRTI) or protease inhibitor (PI) during at least 48 weeks were randomized to four groups (n = 48): 2NRTI + efavirenz (EFV), 2NRTI + EFV + losartan, 2NRTI + raltegravir and 2NRTI + raltegravir + losartan for 48 weeks. Tonsillar biopsy and peripheral blood markers of CD4 and CD8 T-lymphocyte activation and senescence, monocyte activation and soluble markers of inflammation were determined at baseline and at week 48 and compared between groups.

RESULTS

No changes in lymphoid tissue architecture were observed. Adding losartan had no impact on lymphocyte subsets. Conversely, patients who switched to raltegravir showed a higher decrease in all activated [CD4+CD38+HLA-DR+, -0.3 vs. 0.48 (P = 0.033); CD8+CD38+ HLA-DR+, -1.6 vs. 1.3 (P = 0.02)] and senescent [CD4+CD28-CD57+, -0.3 vs. 0.26 (P = 0.04); CD8+CD28-CD57+, -6.1 vs. 3.8 (P = 0.002)] T lymphocytes. In addition, the median CD4/CD8 ratio increased by 0.35 in patients in the raltegravir group vs. 0.03 in the other arms (P = 0.002). Differences between groups in monocyte subpopulations or soluble inflammation markers were not observed.

CONCLUSIONS

Losartan had no effect on lymphoid fibrosis or immune activation/inflammation. Conversely, switching to a regimen with raltegravir significantly decreased activated and senescent T-lymphocyte subpopulations and increased CD4/CD8 ratio in successfully treated PLWH.

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.

Effects of brief stress management interventions on distress and leukocyte nuclear factor kappa B expression during primary treatment for breast cancer: A randomized trial

BACKGROUND

A randomized controlled trial (RCT) of 5-week stress management interventions teaching cognitive behavioral therapy (CBT) or relaxation training (RT) techniques showed decreases in stress and serum inflammatory markers over 12 months in women undergoing treatment for breast cancer (BCa). To understand the molecular mechanisms involved, we examined the effects of these interventions on the transcription factor NF-κB DNA binding activity in leukocytes in parallel with circulating inflammatory markers, stress management skill efficacy and multiple distress indicators.

METHODS

This is a secondary analysis using blood samples of 51 BCa patients (Stage 0-III) with high cancer-specific distress selected from a completed RCT (NCT02103387). Women were randomized to one of three conditions, CBT, RT or health education control (HE). Blood samples and self-reported distress measures (Affects Balance Scale-Negative Affect [ABS-NA], Impact of Events Scale-hyperarousal [IES-H] and intrusive thoughts [IES-I]) were collected at baseline (T0) and 12-month follow-up (T2). Self-reported distress measures and perceived stress management skills (PSMS) were also measured immediately post-intervention (baseline + 2 months: T1). Repeated measures analyses compared changes in distress and NF-κB expression among conditions, controlling for age, stage of cancer, days from surgery to baseline, and receipt of chemotherapy and radiation. Regression analyses related T0 to T2 change in NF-κB expression with T0 to T1 changes in self-reported PSMS and distress measures. Exploratory regression analyses also associated change in NF-κB expression with change in serum cytokines (IL-1β, IL-6 and TNF-α); and s100A8/A9, a circulating inflammatory marker important in breast cancer progression.

RESULTS

There was a significant condition (CBT/RT, HE)xtime (T0, T2) effect on NF-κB, F(1, 39)= 5.267, p = 0.036, wherein NF-κB expression significantly increased over time for HE but did not change for RT or CBT. Greater increases in PSMS from T0 to T1 were associated with less increase in NF-κB expression over 12 months (β = -0.426, t(36) = -2.637, p = 0.048). We found that women assigned to active intervention (CBT/RT) had significant decreases in ABS-NA (F(1, 40)= 6.537, p = 0.028) and IES-I (F(1, 40)= 4.391, p = 0.043) from T0 to T1 compared to women assigned to HE, who showed no change over time (p's > 0.10). For women assigned to CBT or RT, lower NF-κB expression at T2 was related to less ABS-NA, IES-H, and IES-I, all p's < 0.05, although T0-T1 change in distress was not related to T0-T2 change in NF-κB expression for those in an active intervention.

CONCLUSIONS

Brief CBT or RT stress management interventions can mitigate increases in pro-inflammatory leukocyte NF-κB binding over 12 months of primary treatment in highly distressed BCa patients. These effects are likely brought about by improved stress management skills.

Effectiveness, safety, and cost-utility of a knee brace in medial knee osteoarthritis: the ERGONOMIE randomized controlled trial

OBJECTIVE

This pragmatic, multicenter, open-label, randomized controlled trial (RCT) aimed to compare the effectiveness, safety, and cost-utility of a custom-made knee brace versus usual care over 1 year in medial knee osteoarthritis (OA).

DESIGN

120 patients with medial knee OA (VAS pain at rest >40/100), classified as Kellgren-Lawrence grade II-IV, were randomized into two groups: ODRA plus usual care (ODRA group) and usual care alone (UCA group). The primary effectiveness outcome was the change in VAS pain between M0 and M12. Secondary outcomes included changes over 1 year in KOOS (function) and OAKHQOL (quality of life) scores. Drug consumption, compliance, safety of the knee brace, and cost-utility over 1 year were also assessed.

RESULTS

The ODRA group was associated with a higher improvement in: VAS pain (adjusted mean difference of -11.8; 95% CI: -21.1 to -2.5); all KOOS subscales (pain: +8.8; 95% CI: 1.4-16.2); other symptoms (+10.4; 95% CI: 2.7-18); function in activities of daily living (+9.2; 95% CI: 1.1-17.2); function in sports and leisure (+12.3; 95% CI: 4.3-20.3); quality of life (+9.9; 95% CI: 0.9-15.9), OAKHQOL subscales (pain: +14.8; 95% CI: 5.0-24.6); and physical activities (+8.2; 95% CI: 0.6-15.8), and with a significant decrease in analgesics consumption at M12 compared with the UCA group. Despite localized side-effects, observance was good at M12 (median: 5.3 h/day). The ODRA group had a more than 85% chance of being cost-effective for a willingness-to-pay threshold of €45 000 per QALY.

CONCLUSIONS

The ERGONOMIE RCT demonstrated significant clinical benefits of an unloader custom-made knee brace in terms of improvements in pain, function, and some aspects of quality of life over 1 year in medial knee OA, as well as its potential cost-utility from a societal perspective.

Chaperone-mediated autophagy sustains haematopoietic stem-cell function

The activation of mostly quiescent haematopoietic stem cells (HSCs) is a prerequisite for life-long production of blood cells¹. This process requires major molecular adaptations to allow HSCs to meet the regulatory and metabolic requirements for cell division^2-4. The mechanisms that govern cellular reprograming upon stem-cell activation, and the subsequent return of stem cells to quiescence, have not been fully characterized. Here we show that chaperone-mediated autophagy (CMA)⁵, a selective form of lysosomal protein degradation, is involved in sustaining HSC function in adult mice. CMA is required for protein quality control in stem cells and for the upregulation of fatty acid metabolism upon HSC activation. We find that CMA activity in HSCs decreases with age and show that genetic or pharmacological activation of CMA can restore the functionality of old mouse and human HSCs. Together, our findings provide mechanistic insights into a role for CMA in sustaining quality control, appropriate energetics and overall long-term HSC function. Our work suggests that CMA may be a promising therapeutic target for enhancing HSC function in conditions such as ageing or stem-cell transplantation.

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.

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.

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.

Barriers to Women Entering Surgical Careers: A Global Study into Medical Student Perceptions

BACKGROUND

Barriers to female surgeons entering the field are well documented in Australia, the USA and the UK, but how generalizable these problems are to other regions remains unknown.

METHODS

A cross-sectional survey was developed by the International Federation of Medical Students' Associations (IFMSA)'s Global Surgery Working Group assessing medical students' desire to pursue a surgical career at different stages of their medical degree. The questionnaire also included questions on students' perceptions of their education, resources and professional life. The survey was distributed via IFMSA mailing lists, conferences and social media. Univariate analysis was performed, and statistically significant exposures were added to a multivariate model. This model was then tested in male and female medical students, before a further subset analysis by country World Bank income strata.

RESULTS

639 medical students from 75 countries completed the survey. Mentorship [OR 3.42 (CI 2.29-5.12) p = 0.00], the acute element of the surgical specialties [OR 2.22 (CI 1.49-3.29) p = 0.00], academic competitiveness [OR 1.61 (CI 1.07-2.42) p = 0.02] and being from a high or upper-middle-income country (HIC and UMIC) [OR 1.56 (CI 1.021-2.369) p = 0.04] all increased likelihood to be considering a surgical career, whereas perceived access to postgraduate training [OR 0.63 (CI 0.417-0.943) p = 0.03], increased year of study [OR 0.68 (CI 0.57-0.81) p = 0.00] and perceived heavy workload [OR 0.47 (CI 0.31-0.73) p = 0.00] all decreased likelihood to consider a surgical career. Perceived quality of surgical teaching and quality of surgical services in country overall did not affect students' decision to pursue surgery. On subset analysis, perceived poor access to postgraduate training made women 60% less likely to consider a surgical career [OR 0.381 (CI 0.217-0.671) p = 0.00], whilst not showing an effect in the men [OR 1.13 (CI 0.61-2.12) p = 0.70. Concerns about high cost of training halve the likelihood of students from low and low-middle-income countries (LICs and LMICs) considering a surgical career [OR 0.45 (CI 0.25-0.82) p = 0.00] whilst not demonstrating a significant relationship in HIC or UMIC countries. Women from LICs and LMICs were 40% less likely to consider surgical careers than men, when controlling for other factors [OR 0.59 CI (0.342-1.01 p = 0.053].

CONCLUSION

Perceived poor access to postgraduate training and heavy workload dissuade students worldwide from considering surgical careers. Postgraduate training in particular appears to be most significant for women and cost of training an additional factor in both women and men from LMICs and LICs. Mentorship remains an important and modifiable factor in influencing student's decision to pursue surgery. Quality of surgical education showed no effect on student decision-making.

Implication of anti-angiogenic VEGF-A165b in angiogenesis and systolic function after reperfused myocardial infarction

Background

Angiogenesis participates in re-establishing microcirculation after myocardial infarction (MI).

Purpose

In this study, we aim to further understand the role of the anti-angiogenic isoform vascular endothelial growth factor (VEGF)-A165b after MI and explore its potential as a co-adjuvant therapy to coronary reperfusion.

Methods

Two mice MI models were formed: 1) permanent coronary ligation (non-reperfused MI), 2) transient 45-min coronary occlusion followed by reperfusion (reperfused MI); in both models, animals underwent echocardiography before euthanasia at day 21 after MI induction. Serum and myocardial VEGF-A165b levels were determined. In both experimental MI models, functional and structural implication of VEGF-A165b blockade was assessed. In a cohort of 104 ST-segment elevation MI patients, circulating VEGF-A165b levels were correlated with cardiovascular magnetic resonance-derived left ventricular ejection fraction at 6-months and with the occurrence of adverse events (death, heart failure and/or re-infarction).

Results

In both models, circulating and myocardial VEGF-A165b presence was increased 21 days after MI induction. Serum VEGF-A165b levels inversely correlated with systolic function evaluated by echocardiography. VEGF-A165b blockage increased capillary density, reduced infarct size, and enhanced left ventricular function in reperfused, but not in non-reperfused MI experiments. In patients, higher VEGF-A165b levels correlated with depressed ejection fraction and worse outcomes.

Conclusions

In experimental and clinical studies, higher serum VEGF-A165b levels associates with a worse systolic function. Its blockage enhances neoangiogenesis, reduces infarct size, and increases ejection fraction in reperfused, but not in non-reperfused MI experiments. Therefore, VEGF-A165b neutralization represents a potential co-adjuvant therapy to coronary reperfusion.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): This study was funded by “Instituto de Salud Carlos III” and “Fondos Europeos de Desarrollo Regional FEDER” (Exp. PIE15/00013, PI17/01836, PI18/00209 and CIBERCV16/11/00486).

eV-Scale Sterile Neutrino Search Using Eight Years of Atmospheric Muon Neutrino Data from the IceCube Neutrino Observatory

The results of a 3+1 sterile neutrino search using eight years of data from the IceCube Neutrino Observatory are presented. A total of 305 735 muon neutrino events are analyzed in reconstructed energy-zenith space to test for signatures of a matter-enhanced oscillation that would occur given a sterile neutrino state with a mass-squared differences between 0.01 and 100  eV^{2}. The best-fit point is found to be at sin^{2}(2θ_{24})=0.10 and Δm_{41}^{2}=4.5  eV^{2}, which is consistent with the no sterile neutrino hypothesis with a p value of 8.0%.

Characteristics of the Diffuse Astrophysical Electron and Tau Neutrino Flux with Six Years of IceCube High Energy Cascade Data

We report on the first measurement of the astrophysical neutrino flux using particle showers (cascades) in IceCube data from 2010-2015. Assuming standard oscillations, the astrophysical neutrinos in this dedicated cascade sample are dominated (∼90%) by electron and tau flavors. The flux, observed in the sensitive energy range from 16 TeV to 2.6 PeV, is consistent with a single power-law model as expected from Fermi-type acceleration of high energy particles at astrophysical sources. We find the flux spectral index to be γ=2.53±0.07 and a flux normalization for each neutrino flavor of ϕ_{astro}=1.66_{-0.27}^{+0.25} at E_{0}=100  TeV, in agreement with IceCube's complementary muon neutrino results and with all-neutrino flavor fit results. In the measured energy range we reject spectral indices γ≤2.28 at ≥3σ significance level. Because of high neutrino energy resolution and low atmospheric neutrino backgrounds, this analysis provides the most detailed characterization of the neutrino flux at energies below ∼100  TeV compared to previous IceCube results. Results from fits assuming more complex neutrino flux models suggest a flux softening at high energies and a flux hardening at low energies (p value ≥0.06). The sizable and smooth flux measured below ∼100  TeV remains a puzzle. In order to not violate the isotropic diffuse gamma-ray background as measured by the Fermi Large Area Telescope, it suggests the existence of astrophysical neutrino sources characterized by dense environments which are opaque to gamma rays.

[Cardiovascular risk calculators for people living with human immunodeficiency virus]

The increasing access and efficacy of antiretroviral therapy has allowed people living with human immunodeficiency virus to achieve a life expectancy similar to that of the general population. However, this goal may be affected by the increased risk of cardiovascular disease in this group. This risk is multifactorial, involving the high prevalence of traditional risk factors, the development of a pro-inflammatory state related to chronic infection, and the use of antiretroviral drugs with an adverse metabolic profile. In daily practice, in order to estimate this risk and guide medical decision-making, different calculators are available. These are based on data from population cohorts, many of them from human immunodeficiency virusnegative subjects. The main aim of this review is to describe the epidemiology of cardiovascular disease in people living with human immunodeficiency virus, the available risk calculators and their use.