Fear Conditioning by Proxy: The Role of High Affinity Nicotinic Acetylcholine Receptors.

Observational fear-learning studies in genetically modified animals enable the investigation of the mechanisms underlying the social transmission of fear-related information. Here, we used a three-day protocol to examine fear conditioning by proxy (FCbP) in wild-type mice (C57BL/6J) and mice lacking the ß2-subunit of the nicotinic acetylcholine receptor (nAChR). Male animals of both genotypes were exposed to a previously fear-conditioned (FC) cage mate during the presentation of the conditioned stimulus (CS, tone). On the following day, observer (FCbP) mice were tested for fear reactions to the tone: none of the ß2-KO mice froze to the stimulus, while 30% of the wild-type mice expressed significant freezing. An investigation of the possible factors that predicted the fear response revealed that only wild-type mice that exhibited enhanced and more flexible social interaction with the FC cage mate during tone presentations (Day 2) expressed fear toward the CS (Day-3). Our results indicate that (i) FCbP is possible in mice; (ii) the social transmission of fear depends on the interaction pattern between animals during the FCbP session and (iii) ß2-KO mice display a more rigid interaction pattern compared to wild-type mice and are unable to acquire such information. These data suggest that ß2-nAChRs influence observational fear learning indirectly through their effect on social behaviour.

Telehealth and Remote Interventions for Children With Cerebral Palsy: Scoping Review.

BACKGROUND: Remote treatment, or telehealth, has shown promise for children with cerebral palsy (CP) prior to 2020; however, the beginning of the global COVID-19 pandemic limiting access to hospitals for face-to-face treatments has driven the need for telehealth and led to a surge in its development. Due to the recent developments, there has been limited synthesis of the available evidence of telehealth for children with CP. OBJECTIVE: This study aimed to analyze and summarize the existing evidence for telehealth interventions for the treatment of children with CP and identify any areas requiring further research. METHODS: A scoping review was performed. A systematic search of available literature in MEDLINE and PubMed was performed during July 2021. Inclusion criteria for articles were primary research and systematic reviews that investigated telehealth, included children with CP, were published between 2010-2021, and were written in English. Exclusion criteria were secondary research other than systematic reviews; interventions that did not meet the World Health Organization definition of telehealth; or studies where all participants were aged >18 years, children's results were not reported separately, or there were no results reported for children with CP. A scoping review was chosen due to the expected heterogeneity of the participants, as well as the expected small sample sizes and inconsistency of measured outcomes; therefore, a narrative reporting of the results was considered appropriate. RESULTS: In all, 5 papers were identified, which included the results of 11 studies-2 of the included articles were systematic reviews, which included the results of 3 studies each. These 6 studies, together with 5 primary research articles, were included in this scoping review. The existing evidence is of low methodological quality, primarily consisting of case series. There is some evidence that the requirements of telehealth differ depending on the children's developmental stage and functional level. Telehealth is reported to reduce caregiver burden. There is mixed evidence on children's compliance with telehealth. Overall, the results of telehealth interventions for the treatment of children with CP were positive, indicating either comparable or improved results compared with children receiving usual face-to-face care. CONCLUSIONS: The evidence base is lacking in breadth and methodological quality to provide robust clinical recommendations. Most studies investigated hand function only, indicating the limited scope of existing research. However, this review shows that telehealth has demonstrated potential to improve function for children with CP while making health care services more accessible and reducing caregiver burden. Areas requiring further research include telehealth interventions for the lower limb, postural management, and pain control and the barriers to implementing telehealth.

Deficiency of the serine peptidase Kallikrein 6 does not affect the levels and the pathological accumulation of a-synuclein in mouse brain.

Several lines of evidence indicate that the propagation of misfolded α-synuclein (α-syn) plays a central role in the progression and manifestation of Parkinson's disease. Pathogenic α-syn species can be present in the extracellular space. Thus, the identification and modulation of the key enzymes implicated in extracellular α-syn turnover becomes vital. Kallikrein peptidase 6 has been identified as one of the major α-syn degrading enzymes and has been implicated in the clearance of extracellular α-syn. However, the physiological role of this enzyme in regulating α-syn, in vivo, still remains elusive. Here, by utilizing Klk6 knock-out (Klk6-/- ) mice as our experimental model, we provide insight into the physiologic relevance of endogenous KLK6 expression on α-syn processing. Behavioral phenotyping showed that Klk6-/- mice display no gross behavioral abnormalities. Further in vivo characterization of this mouse model, in the context of α-syn accumulation, showed that KLK6 deletion had no impact on the protein levels of intracellular or extracellular α-syn. Upon in vivo administration of α-syn pre-formed fibrils (PFF), α-syn pathologic accumulations were evident both in the brains of Klk6-/- mice and wt mice without significant differences. Intrastriatal delivery of active KLK6, did not affect secreted α-syn levels observed in the A53T α-syn over-expressing mice. These findings suggest that in the in vivo setting of PFF pathology induction, KLK6 alone is not able to modulate pathology transmission. Our study raises implications for the use of recombinant α-syn fibrils in α-syn turnover studies.