Statistics, philosophy, and health: the SMAC 2021 webconference.

SMAC 2021 was a webconference organized in June 2021. The aim of this conference was to bring together data scientists, (bio)statisticians, philosophers, and any person interested in the questions of causality and Bayesian statistics, ranging from technical to philosophical aspects. This webconference consisted of keynote speakers and contributed speakers, and closed with a round-table organized in an unusual fashion.

Fatal Cowpox Virus Infection in Human Fetus, France, 2017.

Cowpox virus (CPXV) has an animal reservoir and is typically transmitted to humans by contact with infected animals. In 2017, CPXV infection of a pregnant woman in France led to the death of her fetus. Fetal death after maternal orthopoxvirus (smallpox) vaccination has been reported; however, this patient had not been vaccinated.

Differential serological and neutralizing antibody dynamics after an infection by a single SARS-CoV-2 strain.

Background: We report here the case of two coworkers infected by the same SARS-CoV-2 strain, presenting two different immunological outcomes.

Case: One patient presented a strong IgG anti-receptor-binding domain immune response correlated with a low and rapidly decreasing titer of neutralizing antibodies. The other patient had a similar strong IgG anti-receptor-binding domain immune response but high neutralizing antibody titers.

Causal reasoning, causal probabilities, and conceptions of causation.

The present paper deals with the tools that can be used to represent causation and to reason about it and, specifically, with their diversity. It focuses on so-called "causal probabilities"--that is, probabilities of effects given one of their causes--and critically surveys a recent paper in which Joyce (2010) argues that the values of these probabilities do not depend on one's conception of causation. I first establish a stronger independence claim: I show that the very definition of causal probabilities is independent of one's conception of causation.

Sympathetic nervous system regulates bone marrow-derived cell egress through endothelial nitric oxide synthase activation: role in postischemic tissue remodeling.

Objective: Catecholamines have been shown to control bone marrow (BM)-derived cell egress, yet the cellular and molecular mechanisms involved in this effect and their subsequent participation to postischemic vessel growth are poorly understood.

Methods And Results: Tyrosine hydroxylase mRNA levels, as well as dopamine (DA) and norepinephrine (NE) contents, were increased in the ischemic BM of mice with right femoral artery ligation. Angiographic score, capillary density, and arteriole number were markedly increased by treatments with DA (IP, 50 mg/kg, 5 days) or NE (IP, 2.

Rapid stress-induced corticosterone rise in the hippocampus reverses serial memory retrieval pattern.

We previously showed that an acute stress (electric footshocks) induced both a rapid plasma corticosterone rise and a reversal of serial memory retrieval pattern in a contextual serial discrimination (CSD) task. This study is aimed at determining (i) if the rapid stress effects on CSD performance are mediated by the hippocampus; (ii) if hippocampal corticosterone membrane receptor activation is involved in the rapid stress effects on CSD performance. In experiment 1, microdialysis in the dorsal hippocampus (dHPC) was used to measure the stress-induced corticosterone rise; in parallel, the effect of acute stress on CSD performance was evaluated.

The hippocampus and prefrontal cortex are differentially involved in serial memory retrieval in non-stress and stress conditions.

We previously showed that 24h after learning, mice significantly remembered the first (D1) but not the second (D2) discrimination in a serial spatial task and that an acute stress delivered 5min before the test phase reversed this memory retrieval pattern. A first experiment evaluated the effects of dorsal hippocampus (HPC) or prefrontal cortex (PFC) lesions, these two brain areas being well-known for their involvement in serial and spatial memory processes. For this purpose, six independent groups of mice were used: non-lesioned (controls), PFC or HPC-lesioned animals, submitted or not to an acute stress (electric footshocks; 0.

Prefrontal cortex or basolateral amygdala lesions blocked the stress-induced inversion of serial memory retrieval pattern in mice.

Previous data from our team have shown that pre-test stress in mice reversed the pattern of memory retrieval in a contextual serial spatial task (CSD; Celerier, A., Pierard, C., Rachbauer, D.

Modafinil restores memory performance and neural activity impaired by sleep deprivation in mice.

The original aims of our study have been to investigate in sleep-deprived mice, the effects of modafinil administration on spatial working memory, in parallel with the evaluation of neural activity level, as compared to non-sleep-deprived animals. For this purpose, an original sleep deprivation apparatus was developed and validated with continuous electroencephalography recording. Memory performance was evaluated using spontaneous alternation in a T-maze, whereas the neural activity level was estimated by the quantification of the c-Fos protein in various cerebral zones.

Modafinil-induced modulation of working memory and plasma corticosterone in chronically-stressed mice.

The original aims of our study were to investigate the dose-effect relationship of modafinil administration on working memory performance, in parallel with the measurement of plasma corticosterone in chronically-stressed mice, as compared to control mice. Memory performance was evaluated by spontaneous alternation in a T-maze. Vehicle or modafinil (8, 16 or 32 mg/kg) were administered after or without chronic stress (immobilization and exposure to light) for 15 min/day over a period of consecutive 14 days.

Mechanism of the hypothermic effect of MPP+ administered centrally in mice.

The neurotoxin methyl phenyl pyridinium (MPP+) was administered intracerebroventricularly (i.c.v.