Identity, regulation and in vivo function of gut NKp46+RORγt+ and NKp46+RORγt- lymphoid cells.

The gut is a major barrier against microbes and encloses various innate lymphoid cells (ILCs), including two subsets expressing the natural cytotoxicity receptor NKp46. A subset of NKp46(+) cells expresses retinoic acid receptor-related orphan receptor γt (RORγt) and produces IL-22, like lymphoid tissue inducer (LTi) cells. Other NKp46(+) cells lack RORγt and produce IFN-γ, like conventional Natural Killer (cNK) cells. The identity, the regulation and the in vivo functions of gut NKp46(+) ILCs largely remain to be unravelled. Using pan-genomic profiling, we showed here that small intestine (SI) NKp46(+)RORγt(-) ILCs correspond to SI NK cells. Conversely, we identified a transcriptional programme conserved in fetal LTi cells and adult SI NKp46(+)RORγt(+) and NKp46(-)RORγt(+) ILCs. We also demonstrated that the IL-1ß/IL-1R1/MyD88 pathway, but not the commensal flora, drove IL-22 production by NKp46(+)RORγt(+) ILCs. Finally, oral Listeria monocytogenes infection induced IFN-γ production in SI NK and IL-22 production in NKp46(+)RORγt(+) ILCs, but only IFN-γ contributed to control bacteria dissemination. NKp46(+) ILC heterogeneity is thus associated with subset-specific transcriptional programmes and effector functions that govern their implication in gut innate immunity.

The Listeria transcriptional landscape from saprophytism to virulence.

The bacterium Listeria monocytogenes is ubiquitous in the environment and can lead to severe food-borne infections. It has recently emerged as a multifaceted model in pathogenesis. However, how this bacterium switches from a saprophyte to a pathogen is largely unknown. Here, using tiling arrays and RNAs from wild-type and mutant bacteria grown in vitro, ex vivo and in vivo, we have analysed the transcription of its entire genome. We provide the complete Listeria operon map and have uncovered far more diverse types of RNAs than expected: in addition to 50 small RNAs (<500 nucleotides), at least two of which are involved in virulence in mice, we have identified antisense RNAs covering several open-reading frames and long overlapping 5' and 3' untranslated regions. We discovered that riboswitches can act as terminators for upstream genes. When Listeria reaches the host intestinal lumen, an extensive transcriptional reshaping occurs with a SigB-mediated activation of virulence genes. In contrast, in the blood, PrfA controls transcription of virulence genes. Remarkably, several non-coding RNAs absent in the non-pathogenic species Listeria innocua exhibit the same expression patterns as the virulence genes. Together, our data unravel successive and coordinated global transcriptional changes during infection and point to previously unknown regulatory mechanisms in bacteria.

Conjugated action of two species-specific invasion proteins for fetoplacental listeriosis.

The ability to cross host barriers is an essential virulence determinant of invasive microbial pathogens. Listeria monocytogenes is a model microorganism that crosses human intestinal and placental barriers, and causes severe maternofetal infections by an unknown mechanism. Several studies have helped to characterize the bacterial invasion proteins InlA and InlB. However, their respective species specificity has complicated investigations on their in vivo role. Here we describe two novel and complementary animal models for human listeriosis: the gerbil, a natural host for L. monocytogenes, and a knock-in mouse line ubiquitously expressing humanized E-cadherin. Using these two models, we uncover the essential and interdependent roles of InlA and InlB in fetoplacental listeriosis, and thereby decipher the molecular mechanism underlying the ability of a microbe to target and cross the placental barrier.

Adherens junctions and pathogen entry.

Epithelia are highly organised structures protecting underlying tissues against microbial pathogens. Epithelial morphogenesis and maintenance is mediated by cell-cell adhesion molecules organised in junctional complexes, such as the adherens junctions. The tight organisation of these complexes and their interactions with cellular factors render the epithelia impermeable to potential invaders. Nevertheless, pathogens have developed strategies to target, interact and manipulate junctional complexes, in order to disrupt or cross the epithelial barriers and cause infection. Bacteria, viruses and parasites access the junctional molecular components either directly, often taking advantage of physiological alterations in epithelial polarity, or indirectly, by delivering into cells molecular factors that destabilise junctional integrity. Importantly, microbial interactions with junctional components are instrumental not only to elucidate mechanisms of invasion, but also to unravel fundamental physiological properties of the epithelial barriers, at the cellular and tissular level.

Five-year morbidity and mortality of patients with ischemia with non-obstructive coronary artery disease and myocardial single-photon emission computed tomography perfusion defects.

INTRODUCTION: Patients with angina and a positive single-photon emission computed tomography (SPECT) scan for reversible ischemia, with no or non-obstructive coronary artery disease (CAD) on invasive coronary angiography (ICA), represent a frequent clinical problem and predicting prognosis is challenging. METHODS: This was a retrospective single-center study on patients who underwent elective ICA with angina and a positive SPECT with no or non-obstructive CAD over a seven-year period. Cardiovascular morbidity, mortality, and major adverse cardiac events were assessed during a follow-up of at least three years after ICA, with the aid of a telephone questionnaire. RESULTS: Data on all patients who underwent ICA in our hospital over a period of seven years (between January 1, 2011 and December 31, 2017) were analyzed. A total of 569 patients fulfilled the pre-specified criteria. In the telephone survey, 285 (50.1%) were successfully contacted and agreed to participate. Mean age was 67.6 (SD 8.8) years (35.4% female) and mean follow-up was 5.53 years (SD 1.85). Mortality was 1.7% (four patients, from non-cardiac causes), 1.7% underwent revascularization, 31 (10.9%) were hospitalized for cardiac reasons and 10.9% reported symptoms of heart failure (no patients with NYHA class>II). Twenty-one had arrhythmic events and only two had mild anginal symptoms. It was also noteworthy that mortality in the uncontacted group (12 out of 284, 4.2%), derived from public social security records, did not differ significantly from the contacted group. CONCLUSIONS: Patients with angina, a positive SPECT for reversible ischemia and no or non-obstructive CAD on ICA have excellent long-term cardiovascular prognosis for at least five years.

CardioPulmonary Resuscitation in patients with suspected or confirmed Covid-19. A consensus of the Working group on CardioPulmonary Resuscitation of the Hellenic Society of Cardiology.

The unprecedented for modern medicine pandemic caused by the SARS-COV-2 virus ("coronavirus", Covid-19 disease) creates in turn new data on the management and survival of cardiac arrest victims, but mainly on the safety of CardioPulmonary Resuscitation (CPR) providers. The Covid-19 pandemic resulted in losses of thousands of lives, and many more people were hospitalized in simple or in intensive care unit beds, both globally and locally in Greece. More specifically, in victims of cardiac arrest, both in- and out- of hospital, the increased mortality and high contagiousness of the SARS-CoV-2 virus posed new questions, of both medical and moral nature/ to CPR providers. What we all know in resuscitation, that we cannot harm the victim and therefore do the most/best we can, is no longer the everyday reality. What we need to know and incorporate into decision-making in the resuscitation process is the distribution of limited human and material resources, the potentially very poor outcome of patients with Covid-19 and cardiac arrest, and especially that a potential infection of health professionals can lead in the lack of health professionals in the near future. This review tries to incorporate the added skills and precautions for CPR providers in terms of both in- and out- hospital CPR.

Parallel Stenting for Treatment of an In-stent Chronic Total Occlusion after Successful Dissection Reentry Technique.

Percutaneous coronary interventions (PCI) for chronic total occlusions (CTO) are the most challenging type of procedure in interventional cardiology and are traditionally associated with increased complexity and reduced procedural success rates. New techniques, such as retrograde approach and dissection reentry technique, offer alternatives in case of traditional antegrade wiring failure. In this paper, we present a successful implantation of a stent parallel to other existing stent in an in-stent CTO (IS-CTO) using dissection reentry technique. The technical details involved and the clues to successful outcome in an individual with in-stent CTO are discussed.

"Ping-pong" technique for treating a balloon uncrossable chronic total occlusion.

Balloon uncrossable lesions are a well-known challenge during chronic total occlusion (CTO) interventions. The technique of using two different catheters into the same coronary artery, the so-called "ping-pong" technique, is a technique described for treating complications during percutaneous coronary intervention (PCI), like perforations or rotational atherectomy burr entrapment. We describe a case where the "ping-pong" technique was successfully used to facilitate treatment of a balloon uncrossable CTO lesion.

Strategies to increase the use of forearm approach during coronary angiography and interventions.

The aim of this article is to focus on the utilization of forearm approach for cardiac catheterization in challenging groups of patients. Radial and ulnar approaches have gained significant popularity among the majority of interventional cardiologists. Multiple studies have demonstrated the feasibility, safety and efficacy of forearm route for cardiac catheterization and have highlighted the significant reduction in bleeding complications by avoiding the puncture of the groin. In this review we present the strategies need to be followed in order to apply the forearm approach in challenging group of patients.

Ventricular bigeminy after subcutaneous administration of apomorphine in a patient with refractory Parkinson's disease: a case report.

Apomorphine is a well established treatment for the management of sudden, unexpected and refractory levodopa-induced "off" states in fluctuating Parkinson's disease either as bolus injections or as continuous infusions. Incidents of atrial fibrillation associated with the administration of the drug have been reported in the past but no incidents of ventricular arrhythmias. We report a case of ventricular bigeminy recorded in a female patient after the administration of apomorphine.

Transcytosis of Listeria monocytogenes across the intestinal barrier upon specific targeting of goblet cell accessible E-cadherin.

Listeria monocytogenes (Lm) is a foodborne pathogen that crosses the intestinal barrier upon interaction between its surface protein InlA and its species-specific host receptor E-cadherin (Ecad). Ecad, the key constituent of adherens junctions, is typically situated below tight junctions and therefore considered inaccessible from the intestinal lumen. In this study, we investigated how Lm specifically targets its receptor on intestinal villi and crosses the intestinal epithelium to disseminate systemically. We demonstrate that Ecad is luminally accessible around mucus-expelling goblet cells (GCs), around extruding enterocytes at the tip and lateral sides of villi, and in villus epithelial folds. We show that upon preferential adherence to accessible Ecad on GCs, Lm is internalized, rapidly transcytosed across the intestinal epithelium, and released in the lamina propria by exocytosis from where it disseminates systemically. Together, these results show that Lm exploits intrinsic tissue heterogeneity to access its receptor and reveal transcytosis as a novel and unanticipated pathway that is hijacked by Lm to breach the intestinal epithelium and cause systemic infection.

Modeling human listeriosis in natural and genetically engineered animals.

Listeria monocytogenes causes listeriosis, a human foodborne infection leading to gastroenteritis, meningoencephalitis and maternofetal infections. InlA and InlB, two L. monocytogenes surface proteins, interact with their respective receptors E-cadherin and Met and mediate bacterial entry into human cultured cells. Here, we present protocols for studying listeriosis in three complementary animal models: (i) the human E-cadherin (hEcad) transgenic mouse line; (ii) the knock-in E16P mouse line; and (iii) the gerbil, in which both InlA-E-cadherin and InlB-Met species-specific interactions occur as in humans. Two routes of infection are described: oral inoculation, the natural route for infection; and intravenous inoculation that bypasses the intestinal barrier. We describe how to monitor L. monocytogenes infection, both qualitatively by imaging techniques and quantitatively by bacterial enumeration. The advantage of these methods over the classical intravenous inoculation of L. monocytogenes in wild-type mice (in which the InlA-E-cadherin interaction does not occur) is that it allows the pathophysiology of listeriosis to be studied in animal models relevant to humans, as they are permissive to the interactions that are thought to mediate L. monocytogenes crossing of human host barriers. The whole procedure (inoculation, in vivo imaging, bacterial enumeration, histopathology) takes one full week to complete, including 3 d of actual experiments.

Evaluation of aortic stiffness (aortic pulse-wave velocity) before and after elective abdominal aortic aneurysm repair procedures: a pilot study.

BACKGROUND: The main clinical criterion for abdominal aortic aneurysm (AAA) repair operations is an AAA diameter >/=5.5 cm. When AAAs increase in size, specific changes occur in the mechanical properties of the aortic wall. Pulse-wave velocity (PWV) has been used as an indicator of vascular stiffness. A low PWV may predict AAA rupture risk and is an early predictor of cardiovascular mortality. METHODS: We investigated the prognostic value of PWV before and after elective AAA repair procedures. Twenty four patients scheduled for an open AAA repair underwent a preoperative carotid-femoral aortic PWV measurement. A second aortic PWV measurement was carried out 6 months postoperatively. RESULTS: The mean aortic PWV increased from 7.84 +/- 1.85 preoperatively to 10.08 +/- 1.57 m/sec 6 months postoperatively (mean change: 2.25; 95% confidence interval 1.4 to 3.1 m/sec; p<0.0001). The preprocedural PWV measurement did not correlate with AAA diameter (Spearman's rank correlation coefficient rho=0.12; p=0.59). CONCLUSIONS: Whether the increase in aortic PWV postoperatively suggests a decreased cardiovascular risk following AAA repair remains to be established. Aortic PWV should also be investigated as an adjunct tool for assessing AAA rupture risk.