Temporal Shift of the Respiratory Syncytial Virus Epidemic Peak for the Years 2020-2023 in Marseille, Southern France.

Respiratory syncytial virus is among the most common causes of respiratory infections. Typically, this viral infection has a seasonality during the cold months but with the SARS-CoV-2 pandemic this has been considerably modified. Here, we studied the epidemiology of this virus in university hospitals of Marseille, South of France, over the period 2020 to 2023. We tested in our laboratory from July 2020 to October 2021 16,516 nasopharyngeal swabs from 16,468 patients for RSV infection using different qPCR assays. We then analyzed data from previous and subsequent winters (from 2018 to 2023) and previous summers (from 2015 to 2021). A total of 676 patients were RSV-positive; their mean age was 3 years and 91 were under 5 years of age. We observed a delay of 4 months of the RSV epidemic's onset compared to other years with an epidemic that peaked in March 2021. We had significantly more RSV-positive cases during summer 2021 compared to previous summers, whereas the incidence of RSV infections was not significantly higher during winter 2022 versus previous winters. Moreover, 494 patients were diagnosed as RSV-positive in the emergency unit and 181 were subsequently hospitalized, and 34 patients were diagnosed RSV-positive while already in the intensive care unit. Over all the study periods, 38 patients diagnosed as RSV-positive died, the majority of whom (23/28) were over 65 years of age. These data show an atypical evolution of the incidence of RSV infections in our city and is another example of the unpredictability of infectious disease epidemiology.

Acute mesenteric ischemia: which predictive factors of delayed diagnosis at emergency unit?

PURPOSE: Acute mesenteric ischemia (AMI) is frequently diagnosed late, leading to a poor prognosis. Our aims were to identify predictive factors of delayed diagnosis and to analyze the outcomes of patients with AMI admitted in emergency units. METHODS: All the patients with AMI (2015-2020), in two Emergency units, were retrospectively included. Two groups were defined according to the time of diagnosis between the arrival at emergency unit and the CT scan: ≤ 6 h (early), > 6 h (delayed). RESULTS: 119 patients (mean age = 71 ± 7 years) were included. The patients with a delayed diagnosis (n = 33, 28%) were significantly associated with atypical presentation, including lower rates of abdominal pain (73 vs 89%, p = 0.003), abdominal tenderness (33 vs 43%, p = 0.03), and plasma lactate (4 ± 2 vs 6 ± 7 mmol/l, p = 0.03) when compared with early diagnosis. After multivariate analysis, the absence of abdominal pain was the only independent predictive factor of delayed diagnosis (Odd Ratio = 0.17; 95% CI = 0.03-0.88, p = 0.03). Patients with delayed diagnosis tended to be associated to lower rates of revascularization (9 vs 17%, p = 0.4), higher rates of major surgical morbidity (90 vs 57%, p = 0.1), longer length of stay (16 ± 23 vs 13 ± 15 days, p = 0.4) and, at the end of follow-up, higher rate of short small bowel syndrome (18 vs 7%, p = 0.095). CONCLUSION: AMI is a challenge for emergency physicians. History of patient, physical exam, biological data are not sufficient to diagnose AMI. New biomarkers, and awareness of emergency physicians should improve and accelerate the diagnosis of AMI.

Adenosine and Adenosine Receptors: Advances in Atrial Fibrillation.

Atrial fibrillation (AF) is the most common arrhythmia in the world. Because the key to developing innovative therapies that limit the onset and the progression of AF is to fully understand the underlying molecular mechanisms of AF, the aim of the present narrative review is to report the most recent advances in the potential role of the adenosinergic system in the pathophysiology of AF. After a comprehensive approach describing adenosinergic system signaling and the mechanisms of the initiation and maintenance of AF, we address the interactions of the adenosinergic system's signaling with AF. Indeed, adenosine release can activate four G-coupled membrane receptors, named A1, A2A, A2B and A3. Activation of the A2A receptors can promote the occurrence of delayed depolarization, while activation of the A1 receptors can shorten the action potential's duration and induce the resting membrane's potential hyperpolarization, which promote pulmonary vein firing, stabilize the AF rotors and allow for functional reentry. Moreover, the A2B receptors have been associated with atrial fibrosis homeostasis. Finally, the adenosinergic system can modulate the autonomous nervous system and is associated with AF risk factors. A question remains regarding adenosine release and the adenosine receptors' activation and whether this would be a cause or consequence of AF.

Adenosine, Adenosine Receptors and Neurohumoral Syncope: From Molecular Basis to Personalized Treatment.

Adenosine is a ubiquitous nucleoside that is implicated in the occurrence of clinical manifestations of neuro-humoral syncope (NHS). NHS is characterized by a drop in blood pressure due to vasodepression together with cardio inhibition. These manifestations are often preceded by prodromes such as headaches, abdominal pain, feeling of discomfort or sweating. There is evidence that adenosine is implicated in NHS. Adenosine acts via four subtypes of receptors, named A1 (A1R), A2A (A2AR), A2B (A2BR) and A3 (A3R) receptors, with all subtypes belonging to G protein membrane receptors. The main effects of adenosine on the cardiovascular system occurs via the modulation of potassium ion channels (IK Ado, K ATP), voltage-gate calcium channels and via cAMP production inhibition (A1R and A3R) or, conversely, through the increased production of cAMP (A2A/BR) in target cells. However, it turns out that adenosine, via the activation of A1R, leads to bradycardia, sinus arrest or atrioventricular block, while the activation of A2AR leads to vasodilation; these same manifestations are found during episodes of syncope. The use of adenosine receptor antagonists, such as theophylline or caffeine, should be useful in the treatment of some forms of NHS. The aim of this review was to summarize the main data regarding the link between the adenosinergic system and NHS and the possible consequences on NHS treatment by means of adenosine receptor antagonists.

Technical and biological review of authorized medical devices for platelets-rich plasma preparation in the field of regenerative medicine.

Platelet-rich plasma (PRP) has seen increased interest and utilization over the past decade, particularly in the field of musculoskeletal disease. This growth has been accompanied by the development of medical devices to realize PRP preparation which includes blood collection, centrifugation, and PRP isolation. The final PRP composition is directly influenced by this preparation step and absence of biological quality control led to a lack of comparability between PRP products that could explain the large variability in the clinical benefit of PRP reported in literature. To circumvent this issue, the scientific community developed different PRP classifications but none of them have been adopted. The goal of this review is to furnish both technical and biological characteristics from PRP commercial systems. On review of 1379 studies, 105 studies were selected according to inclusion criteria for technical analysis and led to the identification of 50 commercial systems that have been classified in three technical categories based on the blood harvesting technique (tubes, syringes or bags). Twelve studies were selected and sufficiently describe biological characteristics from only 14 commercial systems from the 50 identified in the technical analysis. Inclusion of duplicates characterization from a same PRP system lead to the final analysis of 36 PRP preparations that met the inclusion criteria of the biological analysis. All these PRP preparations have been classified among the seven existing classifications. Comparison from all biological parameters and classifications revealed a large heterogeneity among the available current PRP commercial systems. Index of biological sensitivity of classifications to distinguish PRP preparations were also variable. Although these findings should help clinicians in selecting a system that meets their specific needs, this also raises the question to standardize the parameters to biologically define PRP preparation among users and to systematically performed PRP qualification when used.