Biology subjects

Werner, D.

Publications and source records attributed to Werner, D..

6 recordsLinked to original sources

bioRxiv2024

Patterns of neuronal activation following ethanol-induced social facilitation and social inhibition in adolescent cFos-LacZ male and female rats

Motives related to the enhancement of the positive effects of alcohol on social activity within sexes are strongly associated with alcohol use disorder and are a major contributor to adolescent alcohol use and heavy drinking. This is particularly concerning given that heightened vulnerability of the developing adolescent brain. Despite this linkage, it is unknown how adolescent non-intoxicated social behavior relates to alcohols effects on social responding, and how the social brain network differs in response within individuals that are socially facilitated or inhibited by alcohol. Sex effects for social facilitation and inhibition during adolescence are conserved in rodents in high and low drinkers, respectively. In the current study we used cFos-LacZ transgenic rats to evaluate behavior and related neural activity in male and female subjects that differed in their social facilitatory or social inhibitory response to ethanol. Subjects were assessed using social interaction on postnatal days 34, 36 and 38 after a 0, 0.5 and 0.75 g/kg ethanol challenge, respectively, with brain tissue being evaluated following the final social interaction. Subjects were binned into those that were socially facilitated or inhibited by ethanol using a tertile split within each sex. Results indicate that both males and females facilitated by ethanol display lower social activity in the absence of ethanol compared to socially inhibited subjects. Analyses of neural activity revealed that females exhibited differences in 54% of examined socially relevant brain regions of interest (ROIs) compared to only 8% in males, with neural activity in females socially inhibited by ethanol generally being lower than facilitated subjects. Analysis of socially relevant ROI neural activity to social behavior differed for select brain regions as a function of sex, with the prefrontal cortex and nucleus accumbens being negatively correlated in males, but positively correlated in females. Females displayed additional positive correlations in other ROIs, and sex differences were noted across the rostro-caudal claustrum axis. Importantly, neural activity largely did not correlate with locomotor activity. Functional network construction of social brain regions revealed further sex dissociable effects, with 90% interconnectivity in males socially inhibited by ethanol compared to 38% of facilitated subjects, whereas interconnectivity in females inhibited by ethanol was 10% compared to nearly 60% in facilitated subjects. However, hub analyses converged on similar brain regions in males and females, with the nucleus accumbens being a hub region in socially inhibited subjects, whereas the central amygdala was disconnected in facilitated subjects. Taken together, these findings support unified brain regions that contribute to social facilitation or inhibition from ethanol despite prominent sex differences in the social brain network.

animal behavior and cognition↗

bioRxiv2024

Emergence of bluetongue virus serotype 3 in western Germany, October 2023, and ad-hoc monitoring in Culicoides biting midges

Bluetongue virus serotype 3 emerged in October 2023 in Germany, where Schmallenberg virus is enzootic. BTV-3 was detected in a pool of Culicoides biting midges at the same time as infections were reported from ruminants. Schmallenberg virus was frequently found in vector pools, reflecting the epidemiological situation. One sentence summary lineCoinciding with the emergence and low-level circulation of bluetongue virus serotype 3 in ruminants in Germany in October 2023, the virus was detected in a pool of Culicoides biting midges of the Obsoletus Group, while enzootic Schmallenberg virus was found in numerous midge pools.

microbiology↗

bioRxiv2024

Large-Scale COI Gene Data Analysis for the Development of a Gel-Based Multiplex PCR Test Capable of Identifying Biting Midge Vector Species and Haplotypes (Diptera: Ceratopogonidae) of the Culicoides subgenus Avaritia Fox, 1955

The emergence of culicoid-transmitted bluetongue and Schmallenberg viruses in several European countries demonstrated the ability of indigenous biting midge species to transmit pathogens. Entomologic research programmes identified members of the Obsoletus Group (Culicoides subgenus Avaritia) as keyplayers in disease epidemiology in Europe. However, morphological identification of potential vectors to species level is challenging due to the existence of isomorphic species. PCR tests developed to facilitate genetic species determination have been dismantled by the discovery of new genetic variants (haplotypes) of C. obsoletus sensu stricto (s.s.), forming distinct clades. In this study, 4,422 GenBank entries of the mitochondrial cytochrome c oxidase subunit I (COI) gene of subgenus Avaritia members of the genus Culicoides were analyzed to develop a conventional multiplex PCR, capable of detecting all vector species and recently described clades of the western Palaearctic in this subgenus. Numerous GenBank entries incorrectly assigned to a species were identified, analyzed and reassigned. The results suggest that the three clades of C. obsoletus represent independent species, whereas C. montanus should rather be regarded as a genetic variant of C. obsoletus s.s.. Based on these findings, specific primers were designed and validated with DNA material from field-caught biting midges which achieved very high diagnostic sensitivity (100%) when compared to an established reference PCR (82.6%). Hence, the newly developed multiplex PCR represents the first molecular tool which enables both the identification of accepted species and of the three clades of C. obsoletus s.s. and could provide new insights into the ecology of the latter.

genetics↗

bioRxiv2023

Holistic integration of omics data reveals the drivers that shape the ecology of microbial meat spoilage scenarios

The use of omics data for monitoring the microbial flow of fresh meat products along a production line and the development of spoilage prediction tools from these data is a promising but challenging task. In this context, we produced a large multivariate dataset (over 600 samples) obtained on the production lines of two similar types of fresh meat products (poultry and raw pork sausages).We describe a full analysis of this dataset in order to decipher how the spoilage microbial ecology of these two similar products may be shaped differently depending on production parameter characteristics. Our strategy involved a holistic approach to integrate unsupervised and supervised statistical methods on multivariate data (OTU-based microbial diversity; metabolomic data of volatile organic compounds; sensory measurements; growth parameters), and a specific selection of potential uncontrolled (initial microbiota composition) or controlled (packaging type; lactate concentration) drivers. Our results demonstrate that the initial microbiota, which is shown to be very different between poultry and pork sausages, has a major impact on the spoilage scenarios and on the effect that a downstream parameter such as packaging type has on the overall evolution of the microbial community. Depending on the process, we also show that specific actions on the pork meat (such as deboning and defatting) elicit specific food spoilers such as Dellaglioa algida, which becomes dominant during storage. Finally, ecological network reconstruction allowed us to map six different metabolic pathways involved in the production of volatile organic compounds involved in spoilage. We were able connect them to the different bacterial actors and to the influence of packaging type in an overall view. For instance, our results demonstrate a new role of Vibrionaceae in isopropanol production, and of Latilactobacillus fuchuensis and Lactococcus piscium in methanethiol/disylphide production. We also highlight a possible commensal behavior between Leuconostoc carnosum and Latilactobacillus curvatus around 2,3-butanediol metabolism. We conclude that our holistic approach combined with large-scale multi-omic data was a powerful strategy to prioritize the role of production parameters, already known in the literature, that shape the evolution and/or the implementation of different meat spoilage scenarios.

microbiology↗

bioRxiv2023

'Candidatus Tisiphia' is a widespread Rickettsiaceae symbiont in the mosquito Anopheles plumbeus (Diptera: Culicidae)

Symbiotic bacteria alter host biology in numerous ways, including the ability to reproduce or vector disease. Deployment of symbiont control of vector borne disease has focused on Wolbachia interactions with Aedes and is hampered in Anopheles by a lack of compatible symbioses. Previous screening found the symbiont Ca. Tisiphia in Anopheles plumbeus, an aggressive biter and potential secondary vector of malaria parasites and West Nile virus. We screen An. plumbeus samples collected over a ten-year period across Germany and use climate databases to assess environmental influence on incidence. We find a 95% infection rate that does not fluctuate with broad environmental factors. Microscopy suggests the infection is maternally inherited based on strong localisation throughout the ovaries. Finally, we assemble a high-quality draft genome of Ca. Tisiphia to explore its phylogeny and potential metabolism. This strain is closely related to those found in Culicoides midges and shows similar patterns of metabolic potential. An. plumbeus provides a viable avenue of symbiosis research in anopheline mosquitoes, which to date have one other proven infection of a heritable symbiont. Additionally, it provides future opportunity to study the impacts of Ca. Tisiphia on natural and transinfected hosts, especially in relation to reproductive fitness and vector efficiency.

evolutionary biology↗

bioRxiv2022

Ethanol-induced conditioned taste aversion and associated neural activation in male rats: Impact of age and adolescent intermittent ethanol exposure

Individuals that initiate alcohol use at younger ages and binge drink during adolescence are more susceptible to developing alcohol use disorder. Adolescents are relatively insensitive to the aversive effects of alcohol and tend to consume significantly more alcohol per occasion than adults, an effect that is conserved in rodent models. Adolescent typical insensitivity to the aversive effects of alcohol may promote greater alcohol intake by attenuating internal cues that curb its consumption. Attenuated sensitivity to the aversive effects of alcohol is also retained into adulthood following protracted abstinence from adolescent intermittent ethanol (AIE) exposure. Despite these effects, much remains unknown regarding the neural contributors. In the present study, we used a conditioned taste aversion (CTA) paradigm to investigate neuronal activation in late-developing forebrain structures of male adolescents and adult cFos-LacZ transgenic rats as well as in AIE adults following consumption of 0.9% sodium chloride previously paired with an intraperitoneal injection of 0, 1.5 or 2.5g/kg of ethanol.. Unlike adults that were non-manipulated or received water exposure during adolescence, adolescents as well as adults who experienced AIE did not display CTA to a 1.5 g/kg ethanol dose. Adults displayed increased neuronal activation indexed via number of {beta}-galactosidase positive ({beta}-gal+) cells in the prefrontal and insular cortex that was absent in adolescents, whereas adolescents but not adults had reduced number of {beta}-gal+ cells in the central amygdala. Adults also displayed greater cortical-insular functional connectivity than adolescents as well as insular-amygdalar and prefrontal cortex-accumbens core functional connectivity. Like adolescents, adults previously exposed to AIE displayed reduced prefrontal-insular cortex and prefrontal-accumbal core functional connectivity. Taken together, these results suggest that attenuated sensitivity to the aversive effects of ethanol is related to a loss of an insular-prefrontal cortex-accumbens core circuit.

neuroscience↗