Marine heat waves: Characterizing a major climate impact in the Mediterranean

Marine heat waves (MHW), considered as persistent and spatially extensive sea surface temperature (SST) anomalies, have emerged as one of the global change-induced high impact events on the oceans. The study of MHWs received significant progress in recent years, although many unknowns remain. One of the most notable weaknesses is related to the absence of a universally established definition that would allow better intercomparison of results. It is our aim to contribute to this debate by considering the spatial extent to define a MHW. By applying this hypothesis to a relatively small, but complex, basin such as the Mediterranean, MHWs have been characterized and long-term trends assessed from SST satellite data analysis. Our results show that the inclusion of a minimum area threshold, 5 % of the area basin, greatly reduces the population of MHW events by not considering local SST anomalies that do not constitute a MHW event. A trend to more frequent, intense, and longer MHWs is found in the 1982-2021 period in the Mediterranean. In the spatial characterization and long-term trend analysis, regional differences were apparent. Results evidenced variations in MHWs characteristics and trends across the different sub-basins evidencing the fact that, even in a relatively small basin such as the Mediterranean, significant regional differences make it necessary to include a spatial perspective in the studies, beyond purely local analysis at each observation point in a large basin or even in the global ocean. Regarding the characterization of MHWs and trend analysis in the Mediterranean basin, a growing trend has been found in terms of frequency, duration, and intensity that accelerated since 2000 and especially in the last decade, pointing not just to a steady intensification and higher frequency of MHWs but to the emergence of a new set of more intense, long-lasting and spatially extensive MHWs in the recent years.

Is it possible to start quadruple therapy in patients with a new diagnosis of HF and reduced ejection fraction? Real-life data from the TIDY-HF registry

Background

The 2021 European heart failure (HF) guidelines recommended treatment with an inhibitor of the renin-angiotensin-aldosterone axis (RAAS), a beta-blocker (BB), a mineralocorticoid receptor antagonist (MRA), and a cotransporter sodium-glucose type 2 inhibitor (SGLT2) in patients with HF and left ventricular ejection fraction (LVEF) ≤40%. However, there is little evidence on implementing quadruple therapy in clinical practice.

Purpose

Study the implementation of quadruple therapy in patients with a new diagnosis of HF and reduced ejection fraction in clinical practice.

Methods

A prospective multicenter registry (38 centers in Spain) was carried out, including all patients newly diagnosed with HF with LVEF ≤40% in clinical practice. Their baseline and laboratory characteristics were recorded and their pharmacological treatment: at baseline (discharged from hospitalization or first outpatient visit within a maximum period of 1 month after the echocardiographic diagnosis), one month, and 3 months later.

Results

On 1th of March 2022, 349 patients were included, with baseline treatment data in 289. The mean age was 65.0±14.2 years, and 72.1% were men. The mean LVEF was 28.5±7.3%, with 57.6% in NYHA II and 29.1% in NYHA III–IV. The most frequent causes of cardiomyopathy were: ischemic (25.1%), tachycardiomyopathy (16.6%), and idiopathic (15.7%). 46.4% were dyslipidemic, 57.5% hypertensive and 33.3% diabetic. 65.1% of the patients were in sinus rhythm. Before HF diagnosis, 44.6% had been treated with RAASi, 22.8% with BB, 7.8% with MRA, 8.1% with iSGLT2, and 24.5% with diuretics. The drugs used at baseline and the changes during follow-up are shown in Table 1.

Conclusions

According to our cohort, almost 60% of newly diagnosed patients with HF and reduced LVEF start quadruple therapy during the first month after diagnosis, with sacubitril/valsartan being the preferred RAASi in most cases. The implementation of drugs with prognostic benefit is above 70% at baseline and exceeds 80% at one month of follow-up, with a progressive reduction in loop diuretics during follow-up.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Spanish Society of Cardiology

Implication of REDD1 in the activation of inflammatory pathways

In response to endotoxemia, the organism triggers an inflammatory response, and the visceral adipose tissue represents a major source of proinflammatory cytokines. The regulation of inflammation response in the adipose tissue is thus of crucial importance. We demonstrated that Regulated in development and DNA damage response-1 (REDD1) is involved in inflammation. REDD1 expression was increased in response to lipopolysaccharide (LPS) in bone marrow derived macrophages (BMDM) and in epidydimal adipose tissue. Loss of REDD1 protected the development of inflammation, since the expression of proinflammatory cytokines (TNFα, IL-6, IL-1β) was decreased in adipose tissue of REDD1^−/− mice injected with LPS compared to wild-type mice. This decrease was associated with an inhibition of the activation of p38MAPK, JNK, NF-κB and NLRP3 inflammasome leading to a reduction of IL-1β secretion in response to LPS and ATP in REDD1^−/− BMDM. Although REDD1 is an inhibitor of mTORC1, loss of REDD1 decreased inflammation independently of mTORC1 activation but more likely through oxidative stress regulation. Absence of REDD1 decreases ROS associated with a dysregulation of Nox-1 and GPx3 expression. Absence of REDD1 in macrophages decreases the development of insulin resistance in adipocyte-macrophage coculture. Altogether, REDD1 appears to be a key player in the control of inflammation.

Hypoxia inhibits Cavin-1 and Cavin-2 expression and down-regulates caveolae in adipocytes

During obesity, a hypoxic state develops within the adipose tissue, resulting in insulin resistance. To understand the underlying mechanism, we analyzed the involvement of caveolae because they play a crucial role in the activation of insulin receptors. In the present study, we demonstrate that in 3T3-L1 adipocytes, hypoxia induces the disappearance of caveolae and inhibits the expression of Cavin-1 and Cavin-2, two proteins necessary for the formation of caveolae. In mice, hypoxia induced by the ligature of the spermatic artery results in the decrease of cavin-1 and cavin-2 expression in the epididymal adipose tissue. Down-regulation of the expression of cavins in response to hypoxia is dependent on hypoxia-inducible factor-1. Indeed, the inhibition of hypoxia-inducible factor-1 restores the expression of cavins and caveolae formation. Expression of cavins regulates insulin signaling because the silencing of cavin-1 and cavin-2 impairs insulin signaling pathway. In human, cavin-1 and cavin-2 are decreased in the sc adipose tissue of obese diabetic patients compared with lean subjects. Moreover, the expression of cavin-2 correlates negatively with the homeostatic model assessment index of insulin resistance and glycated hemoglobin level. In conclusion, we propose a new mechanism in which hypoxia inhibits cavin-1 and cavin-2 expression, resulting in the disappearance of caveolae. This leads to the inhibition of insulin signaling and the establishment of insulin resistance.

A new approach based on Machine Learning for predicting corneal curvature (K1) and astigmatism in patients with keratoconus after intracorneal ring implantation

Keratoconus (KC) is the most common type of corneal ectasia. A corneal transplantation was the treatment of choice until the last decade. However, intra-corneal ring implantation has become more and more common, and it is commonly used to treat KC thus avoiding a corneal transplantation. This work proposes a new approach based on Machine Learning to predict the vision gain of KC patients after ring implantation. That vision gain is assessed by means of the corneal curvature and the astigmatism. Different models were proposed; the best results were achieved by an artificial neural network based on the Multilayer Perceptron. The error provided by the best model was 0.97D of corneal curvature and 0.93D of astigmatism.

Idiotype vaccines for human B-cell malignancies

After twenty years of use in humans, customized idiotypic vaccination yet remains a non-approved, experimental therapeutic option for patients with lymphoma and myeloma. Potentially applicable to all B-cell malignancies whose cells express a clonal immunoglobulin or its epitopes on their surface, this treatment is designed to prevent disease recurrence or progression. Mostly used in follicular lymphoma patients so far, idiotype vaccines have clearly shown biological efficacy, clinical efficacy and clinical benefit in this setting, although no study aiming at regulatory approval of the procedure has been able to meet its main clinical endpoints. In mantle cell lymphoma, only biological efficacy has been proven for idiotypic vaccination, while in multiple myeloma a limited number of studies support the notion of biological and perhaps even clinical efficacy, although no credible evidence of clinical benefit has still emerged. Idiotype vaccines have been produced and administered in a number of substantially different manners. Therefore, the results of most clinical trials cannot be easily compared, and even less pooled together in meaningful meta-analyses. A more creative and yet scientifically sound way to design clinical trials of customized active immunotherapies will be key to the future development of idiotype vaccines, particularly considering that we currently lack any clinical or biological indicator to possibly predict which patients are more likely to respond to idiotypic vaccination from an immunologic point of view. This review aims at summarizing the multifaceted success achieved by idiotype vaccines, as well as at outlining the challenges awaiting them in the near future: how to improve feasibility, immunogenicity and efficacy, as well as how to confirm benefit and gain regulatory approval.

Anti-Inflammatory Cytokines Induce Lipopolysaccharide Tolerance in Human Monocytes Without Modifying Toll-Like Receptor 4 Membrane Expression

Toll-like receptor 4 (TLR4) participates in innate immunity by detecting lipopolysaccharides (LPS) of Gram-negative bacterial cell walls. TLR4 macrophage expression in mice is modulated by LPS. This fact constitutes, at least partially, the molecular basis for LPS tolerance. Very recently, the effect of interferon-gamma (IFN-gamma), a pro-inflammatory cytokine, has been described on TLR4 membrane expression of human monocytes. IFN-gamma up-regulates TLR4 expression and antagonizes the LPS-induced TLR4 down-regulation. These data prompted us to study the expression of membrane TLR4 in human mono- cytes in which LPS tolerance was induced by LPS and by anti-inflammatory cytokines [interleukin-10 (IL-10) and transforming growth factor beta1 (TGFbeta1)]. Data concerning this latter model, and more specifically, the effect of anti-inflammatory cytokines over TLR4 expression, are not available at present. We show here that membrane TLR4 expression in human monocytes falls after LPS exposure. The effect was prolonged for 12 h, but then expression returned to normal levels. The incubation of human monocytes with IL-10, TGFbeta1 or a mixture of both induces no alterations in membrane TLR4 expression. However, these cytokines are able to substitute the tolerizing LPS exposure in order to induce LPS tolerance. Our data help to achieve a better understanding of the way cytokines control the cellular expression of TLR.

Patterns of epithelial cell death during early development of the human inner ear

A light microscopic study of cell death in a developmental series of otic primordia from 23 human embryos (Carnegie stages 9 to 14) was completed. Degenerated cells were noted predominantly in the placode (stages 9 and 10), cup (stages 11 and 12), and otocyst (stages 13 and 14). A systematic camera lucida study of the appearance and topography of degenerating epithelial cells showed four different areas of cell death in the otic primordia that related to 1) invagination and detachment of the otic anlage, 2) early histogenesis of the statoacoustic ganglion, and 3) development of the endolymphatic duct. The possible role of cell death in the morphogenesis of the inner ear related to morphogenetic movements is discussed.

[Farmer's lung. Report of a case (author's transl)]

Asthenia, anorexia, fever, weight loss, dyspnea and cough developed insidiously over 3 months in a patient working in a farm and exposed to moldy organic dusts (hay and alfalfa). Complete recovery occurred when exposure was stopped, but symptoms reappeared when the patient took the same job again. Pulmonary function tests showed reduced compliance and diffusion of gases. The demonstration of precipitating antibodies to moldy hay extracts confirmed the diagnosis of farmer's lung. Eight months after discontinuance of exposure and on steroid therapy the patient was asymptomatic with spirometric values within normal limits. Chest roentgenogram showed a residual finely reticular pattern in the superior lobules. The importance of an early diagnosis and subsequent change of job in order to avoid irreversible pulmonary fibrosis is stressed.

[Bouveret's syndrome. Two new cases (author's transl)]

Pyloro-duodenal obstruction by a gall-stone which has passed through a bilio-digestive fistula (Bouveret's syndrome) is rare. The authors report two cases. The clinical picture is that of pyloric obstruction. The diagnosis, suspected on barium meal, is today confirmed by fibre endoscopy. The treatment is fairly simple: cholecystectomy, removal of the gall stone, closure of the fistula; the prognosis depends on the general context.