Changes in Risk Perceptions During the 2014 Ebola Virus Disease Epidemic: Results of Two Consecutive Surveys Among the General Population in Lower Saxony, Germany

Background: The Ebola virus disease (EVD) outbreak 2014 received extensive news media coverage, which faded out before the outbreak ended. News media coverage impacts risk perception; it is, however, unclear if the components of risk perception (affective and cognitive responses) change differently over time. Methods: In an online panel, we asked participants (n = 1376) about EVD risk perceptions at the epidemic\u27s peak (November 2014) and after news media coverage faded out (August 2015). We investigated worry (affective response), perceived likelihood of infection, perceived personal impact, and coping efficacy (dimensions of cognitive response), and knowledge about transmission. Differences between the surveys with respect to manifestations of affective and cognitive dimensions were tested using the Wilcoxon signed-rank test. The association between individual change in knowledge and worries about EVD in the first survey was investigated using linear regression. Results: In November 2014, the survey was filled in by 974 participants. Ten months later, 662 of them were still members of the online panel and were invited to the follow-up survey. Among the 620 respondents, affective response decreased between the surveys. Knowledge about EVD also decreased; however, participants worried about EVD in 2014 had increased knowledge in 2015. Perceived likelihood of infection decreased over time, while perceived personal impact and coping efficacy did not. Conclusions: Risk communication appealing to cognitive reactions by informing clearly on the risk of infection in unaffected countries may decrease inappropriate behaviors

The Cl(-)-channel TMEM16A is involved in the generation of cochlear Ca(2+) waves and promotes the refinement of auditory brainstem networks in mice

Before hearing onset (postnatal day 12 in mice), inner hair cells (IHC) spontaneously fire action potentials thereby driving pre-sensory activity in the ascending auditory pathway. The rate of IHC action potential bursts is modulated by inner supporting cells (ISC) of Kölliker's organ through the activity of the Ca(2+) activated Cl(-) channel TMEM16A (ANO1). Here we show that conditional deletion of Ano1 (Tmem16a) in mice disrupts Ca(2+) waves within Kölliker's organ, reduces the burst firing activity and the frequency-selectivity of auditory brainstem neurons in the medial nucleus of the trapezoid body (MNTB), and also impairs the functional refinement of MNTB projections to the lateral superior olive (LSO). These results reveal the importance of the activity of Kölliker's organ for the refinement of central auditory connectivity. In addition, our study suggests involvement of TMEM16A in the propagation of Ca(2+) waves, which may also apply to other tissues expressing TMEM16A

Persistence of functional memory B cells recognizing SARS-CoV-2 variants despite loss of specific IgG

Although some COVID-19 patients maintain SARS-CoV-2-specific serum immunoglobulin G (IgG) for more than 6 months postinfection, others eventually lose IgG levels. We assessed the persistence of SARS-CoV-2-specific B cells in 17 patients, 5 of whom had lost specific IgGs after 5–8 months. Differentiation of blood-derived B cells in vitro revealed persistent SARS-CoV-2-specific IgG B cells in all patients, whereas IgA B cells were maintained in 11. Antibodies derived from cultured B cells blocked binding of viral receptor-binding domain (RBD) to the cellular receptor ACE-2, had neutralizing activity to authentic virus, and recognized the RBD of the variant of concern Alpha similarly to the wild type, whereas reactivity to Beta and Gamma were decreased. Thus, differentiation of memory B cells could be more sensitive for detecting previous infection than measuring serum antibodies. Understanding the persistence of SARS-CoV-2-specific B cells even in the absence of specific serum IgG will help to promote long-term immunity

Distinct glutaminyl cyclase expression in Edinger–Westphal nucleus, locus coeruleus and nucleus basalis Meynert contributes to pGlu-Aβ pathology in Alzheimer’s disease

Glutaminyl cyclase (QC) was discovered recently as the enzyme catalyzing the pyroglutamate (pGlu or pE) modification of N-terminally truncated Alzheimer’s disease (AD) Aβ peptides in vivo. This modification confers resistance to proteolysis, rapid aggregation and neurotoxicity and can be prevented by QC inhibitors in vitro and in vivo, as shown in transgenic animal models. However, in mouse brain QC is only expressed by a relatively low proportion of neurons in most neocortical and hippocampal subregions. Here, we demonstrate that QC is highly abundant in subcortical brain nuclei severely affected in AD. In particular, QC is expressed by virtually all urocortin-1-positive, but not by cholinergic neurons of the Edinger–Westphal nucleus, by noradrenergic locus coeruleus and by cholinergic nucleus basalis magnocellularis neurons in mouse brain. In human brain, QC is expressed by both, urocortin-1 and cholinergic Edinger–Westphal neurons and by locus coeruleus and nucleus basalis Meynert neurons. In brains from AD patients, these neuronal populations displayed intraneuronal pE-Aβ immunoreactivity and morphological signs of degeneration as well as extracellular pE-Aβ deposits. Adjacent AD brain structures lacking QC expression and brains from control subjects were devoid of such aggregates. This is the first demonstration of QC expression and pE-Aβ formation in subcortical brain regions affected in AD. Our results may explain the high vulnerability of defined subcortical neuronal populations and their central target areas in AD as a consequence of QC expression and pE-Aβ formation

Reliability of Synaptic Transmission at the Synapses of Held In Vivo under Acoustic Stimulation

BACKGROUND:The giant synapses of Held play an important role in high-fidelity auditory processing and provide a model system for synaptic transmission at central synapses. Whether transmission of action potentials can fail at these synapses has been investigated in recent studies. At the endbulbs of Held in the anteroventral cochlear nucleus (AVCN) a consistent picture emerged, whereas at the calyx of Held in the medial nucleus of the trapezoid body (MNTB) results on the reliability of transmission remain inconsistent. In vivo this discrepancy could be due to the difficulty in identifying failures of transmission. METHODS/FINDINGS:We introduce a novel method for detecting unreliable transmission in vivo. Based on the temporal relationship between a cells' waveform and other potentials in the recordings, a statistical test is developed that provides a balanced decision between the presence and the absence of failures. Its performance is quantified using simulated voltage recordings and found to exhibit a high level of accuracy. The method was applied to extracellular recordings from the synapses of Held in vivo. At the calyces of Held failures of transmission were found only rarely. By contrast, at the endbulbs of Held in the AVCN failures were found under spontaneous, excited, and suppressed conditions. In accordance with previous studies, failures occurred most abundantly in the suppressed condition, suggesting a role for inhibition. CONCLUSIONS/SIGNIFICANCE:Under the investigated activity conditions/anesthesia, transmission seems to remain largely unimpeded in the MNTB, whereas in the AVCN the occurrence of failures is related to inhibition and could be the basis/result of computational mechanisms for temporal processing. More generally, our approach provides a formal tool for studying the reliability of transmission with high statistical accuracy under typical in vivo recording conditions

Comparative physiology of Australian quolls (Dasyurus; Marsupialia)

Quolls (Dasyurus) are medium-sized carnivorous dasyurid marsupials. Tiger (3,840 g) and eastern quolls (780 g) are mesic zone species, northern quolls (516 g) are tropical zone, and chuditch (1,385 g) were once widespread through the Australian arid zone. We found that standard physiological variables of these quolls are consistent with allometric expectations for marsupials. Nevertheless, inter-specific patterns amongst the quolls are consistent with their different environments. The lower T ^sub b^ of northern quolls (34°C) may provide scope for adaptive hyperthermia in the tropics, and they use torpor for energy/water conservation, whereas the larger mesic species (eastern and tiger quolls) do not appear to. Thermolability varied from little in eastern (0.035°C °C^sup -1^) and tiger quolls (0.051°C ºC^sup -1^) to substantial in northern quolls (0.100°C ºC^sup -1^) and chuditch (0.146°C ºC^sup -1^), reflecting body mass and environment. Basal metabolic rate was higher for eastern quolls (0.662 ± 0.033 ml O^sub 2^ g^sup -1^ h^sup -1^), presumably reflecting their naturally cool environment. Respiratory ventilation closely matched metabolic demand, except at high ambient temperatures where quolls hyperventilated to facilitate evaporative heat loss; tiger and eastern quolls also salivated. A higher evaporative water loss for eastern quolls (1.43 ± 0.212 mg H^sub 2^O g^sup -1^ h^sup -1^) presumably reflects their more mesic distribution. The point of relative water economy was low for tiger (-1.3°C), eastern (-12.5°C) and northern (+3.3) quolls, and highest for the chuditch (+22.6°C). We suggest that these differences in water economy reflect lower expired air temperatures and hence lower respiratory evaporative water loss for the arid-zone chuditch relative to tropical and mesic quolls

Estimates of protection levels against SARS-CoV-2 infection and severe COVID-19 in Germany before the 2022/2023 winter season: the IMMUNEBRIDGE project

PURPOSE: Despite the need to generate valid and reliable estimates of protection levels against SARS-CoV-2 infection and severe course of COVID-19 for the German population in summer 2022, there was a lack of systematically collected population-based data allowing for the assessment of the protection level in real time. METHODS: In the IMMUNEBRIDGE project, we harmonised data and biosamples for nine population-/hospital-based studies (total number of participants n = 33,637) to provide estimates for protection levels against SARS-CoV-2 infection and severe COVID-19 between June and November 2022. Based on evidence synthesis, we formed a combined endpoint of protection levels based on the number of self-reported infections/vaccinations in combination with nucleocapsid/spike antibody responses ("confirmed exposures"). Four confirmed exposures represented the highest protection level, and no exposure represented the lowest. RESULTS: Most participants were seropositive against the spike antigen; 37% of the participants ≥ 79 years had less than four confirmed exposures (highest level of protection) and 5% less than three. In the subgroup of participants with comorbidities, 46-56% had less than four confirmed exposures. We found major heterogeneity across federal states, with 4-28% of participants having less than three confirmed exposures. CONCLUSION: Using serological analyses, literature synthesis and infection dynamics during the survey period, we observed moderate to high levels of protection against severe COVID-19, whereas the protection against SARS-CoV-2 infection was low across all age groups. We found relevant protection gaps in the oldest age group and amongst individuals with comorbidities, indicating a need for additional protective measures in these groups