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The Charité – Universitätsmedizin Berlin obtained in January 2021 the license of the app “Complete Anatomy” (3D4Medical/Elsevier) to offer an additional anatomical learning and teaching possibility for students and educators. Especially the COVID-19 pandemic showed the advantages of digital learning and teaching possibilities. Also beyond the restricted contact teaching, digital learning is a valuable support for students’ education. We conducted a survey to gain a current pattern of opinion regarding the individual usage of and satisfaction with the app among medical and dental students as well as anatomical educators at the Charité – Universitätsmedizin Berlin and to improve the use of digital learning devices within dental and medical education.

Background: Recent decades have seen controversial discussions on the validity of dissection courses in medical education, with alternative programs tested for various reasons. On April 1, 2015 the classification of formaldehyde as a hazardous substance was upgraded by the EU, leding to some universities precluding the participation of pregnant and breastfeeding students in dissection course. However, the revision to the Maternity Protection Act, implemented in Germany on January 1, 2018, now protects student mothers from being disadvantaged in their studies as a consequence of their pregnancy or breastfeeding. Therefore, universities must offer alternatives to dissection courses using formaldehyde to these female students.Project description: As an alternative to regular dissection courses, which use the abovementioned chemical, the Centre for Anatomy at Charité has opted for developing dedicated courses for student mothers. These new courses use plastinated prosection material instead of formalin-treated cadavers of body donors. As the core of the anatomical education takes place during the third and fourth semester in the current curriculum of human medicine at Charité the alternative courses are limited to those two semesters. Additionally, alternative exams at the end of both semesters had to be developed. The alternative courses were designed to offer pregnant and breastfeeding students a study program as close as possible to the one in which their peers learn human anatomy.Results: For the new courses, plastinates had to be produced and further specimens are still needed. Additionally required sets of bones, models and radiological images were readily available at the Centre for Anatomy. The planning and conceptualization of the courses took half a year of intense preparation. The courses for the third and fourth semester were first running during summer semester 2017. There is a clear demand for courses among pregnant and breastfeeding students. At least 5 student participants per course were registered, corresponding to every fortieth female student in their semester cohorts. The highest number of student participants was 13 in one course so far. The performances of the participants in the anatomical examinations were matching that of students attending the regular courses.Discussion: The alternative macroscopic anatomy courses enable the implementation of the revised Maternity Protection Act. The targeted student group is highly satisfied with the offered alternative courses. Considering the number of participants and their examination performance so far, the Centre for Anatomy regards the efforts involved in planning and implementing the courses as justified. The courses allow pregnant and breastfeeding students to address the same anatomical themes at the same time as their fellow students. However, due to restricted flexibility of plastinates and because students cannot prepare specific anatomical structures independently the scope of topographic learning is limited. That being said, well-produced plastinates can display anatomical structures which often cannot be dissected in regular courses. The alternative macroscopic anatomy courses using plastinates constitute suitable alternatives to the regular dissection courses with formalin-treated cadavers for pregnant and breastfeeding students.

Background: Students within a cohort might employ unique subsets of learning strategies (LS) to study. However, little research has aimed to elucidate subgroup‐specific LS usage among medical students. Recent methodological developments, particularly person‐centred approaches such as latent profile analysis (LPA), offer ways to identify relevant subgroups with dissimilar patterns of LS use. In this paper, we apply LPA to explore subgroups of medical students during preclinical training in anatomy and examine how these patterns are linked with learning outcomes. Methods: We analysed the LS used by 689 undergraduate, 1st and 2nd‐year medical students across 6 German universities who completed the short version of the Learning Strategies of University Students (LIST‐K) questionnaire, and answered questions towards external criteria such as learning resources and performance. We used the thirteen different LS facets of the LIST‐K (four cognitive, three metacognitive, three management of internal and three management of external resources) as LPA indicators. Results: Based on LPA, students can be grouped into four distinct learning profiles: Active learners (45% of the cohort), collaborative learners (17%), structured learners (29%) and passive learners (9%). Students in each of those latent profiles combine the 13 LS facets in a unique way to study anatomy. The profiles differ in both, the overall level of LS usage, and unique combinations of LS used for learning. Importantly, we find that the facets of LS show heterogeneous and subgroup‐specific correlations with relevant outcome criteria, which partly overlap but mostly diverge from effects observed on the population level. Conclusions: The effects observed by LPA expand results from variable‐centered efforts and challenge the notion that LS operate on a linear continuum. These results highlight the heterogeneity between subgroups of learners and help generate a more nuanced interpretation of learning behaviour. Lastly, our analysis offers practical implications for educators seeking to tailor learning experiences to meet individual student needs. Darici et al. explore medical students' learning strategies, identifying four distinct profiles that help to highlight how learning is rarely a linear journey. [ABSTRACT FROM AUTHOR]

The heterotrimeric G‐protein αo subunit is ubiquitously expressed in the CNS as two splice variants Gαo1 and Gαo2, regulating various brain functions. Here, we investigated the effect of single Gαo1, Gαo2, and double Gαo1/2 knockout on the postnatal development of the murine mossy fiber tract, a central pathway of the hippocampal connectivity circuit. The size of the hippocampal synaptic termination fields covered by mossy fiber boutons together with various fiber length parameters of the tract was analyzed by immunohistochemical staining of the vesicular Zinc transporter 3 (ZnT3) or Synaptoporin at postnatal days 2, 4, 8, 12, 16, and in the adult. Ultimately, Gαo1 knockout resulted in a reduced developmental growth of synaptic mossy fiber terminal fields by 37% in the adult Stratum lucidum and by 30% in the total mossy fiber tract size. Other morphological parameters such as projection length of the infrapyramidal bundle of the tract were increased (+52% in Gαo1−/− mice). In contrast, Gαo2 knockout had no effects on the mossy fiber tract. Moreover, by using primary heterozygous and homozygous Gαo1 knockout hippocampal cultures, we detected a strongly pronounced reduction in axon and dendrite length (−50% and −38%, respectively) as well as axon and dendrite arborization complexity (−75% and −72% branch nodes, respectively) in the homozygous knockout. Deletion of both splice variants Gαo1 and Gαo2 partially rescued the in vivo and completely reconstituted the in vitro effects, indicating an opposing functional relevance of the two Gαo splice variants for neuronal development and synaptic connectivity. [ABSTRACT FROM AUTHOR]

The calcium-dependent activator proteins for secretion (CAPS) are priming factors for synaptic and large dense-core vesicles (LDCVs), promoting their entry into and stabilizing the release-ready state. A modulatory role of CAPS in catecholamine loading of vesicles has been suggested. Although an influence of CAPS on monoamine transporter function and on vesicle acidification has been reported, a role of CAPS in vesicle loading is disputed. Using expression of naturally occurring splice variants of CAPS2 into chromaffin cells from CAPS1/CAPS2 double-deficient mice of both sexes, we show that an alternative exon of 40 aa is responsible for enhanced catecholamine loading of LDCVs in mouse chromaffin cells. The presence of this exon leads to increased activity of both vesicular monoamine transporters. Deletion of CAPS does not alter acidification of vesicles. Our results establish a splice-variant-dependent modulatory effect of CAPS on catecholamine content in LDCVs. [ABSTRACT FROM AUTHOR]

The segregation between vesicular glutamate and GABA storage and release forms the molecular foundation between excitatory and inhibitory neurons and guarantees the precise function of neuronal networks. Using immunoisolation of synaptic vesicles, we now show that VGLUT2 and VGAT, and also VGLUT1 and VGLUT2, coexist in a sizeable pool of vesicles. VGAT immunoisolates transport glutamate in addition to GABA. Furthermore, VGLUT activity enhances uptake of GABA and monoamines. Post embedding immunogold double labeling revealed that VGLUT1, VGLUT2, and VGAT coexist in mossy fiber terminals of the hippocampal CA3 area. Similarly, cerebellar mossy fiber terminals harbor VGLUT1, VGLUT2, and VGAT, while parallel and climbing fiber terminals exclusively contain VGLUT1 or VGLUT2, respectively. VGLUT2 was also observed in cerebellar GABAergic basket cells terminals. We conclude that the synaptic coexistence of vesicular glutamate and GABA transporters allows for corelease of both glutamate and GABA from selected nerve terminals, which may prevent systemic overexcitability by downregulating synaptic activity. Furthermore, our data suggest that VGLUT enhances transmitter storage in nonglutamatergic neurons. Thus, synaptic and vesicular coexistence of VGLUT and VGAT is more widespread than previously anticipated, putatively influencing fine-tuning and control of synaptic plasticity. [ABSTRACT FROM AUTHOR]

Synaptic vesicles (SVs) store neurotransmitters and release them by exocytosis. The vesicular neurotransmitter transporters discriminate which transmitter will be sequestered and stored by the vesicles. However, it is unclear whether the neurotransmitter phenotype of SVs is solely defined by the transporters or whether it is associated with additional proteins. Here we have compared the protein composition of SVs enriched in vesicular glutamate (VGLUT-1) and GABA transporters (VGAT), respectively, using quantitative proteomics. Of >450 quantified proteins, ~50 were differentially distributed between the populations, with only few of them being specific for SVs. Of these, the most striking differences were observed for the zinc transporter ZnT3 and the vesicle proteins SV2B and SV31 that are associated preferentially with VGLUT-1 vesicles, and for SV2C that is associated mainly with VGAT vesicles. Several additional proteins displayed a preference for VGLUT-1 vesicles including, surprisingly, synaptophysin, synaptotagmins, and syntaxin 1a. Moreover, MAL2, a membrane protein of unknown function distantly related to synaptophysins and SCAMPs, cofractionated with VGLUT-1 vesicles. Both subcellular fractionation and immunolocalization at the light and electron microscopic level revealed that MAL2 is a bona-fide membrane constituent of SVs that is preferentially associated with VGLUT-1-containing nerve terminals. We conclude that SVs specific for different neurotransmitters share the majority of their protein constituents, with only few vesicle proteins showing preferences that, however, are nonexclusive, thus confirming that the vesicular transporters are the only components essential for defining the neurotransmitter phenotype of a SV. [ABSTRACT FROM AUTHOR]

Classical neurotransmitters, including monoamines, acetylcholine, glutamate, GABA, and glycine, are loaded into synaptic vesicles by means of specific transporters. Vesicular monoamine transporters are under negative regulation by α subunits of trimeric G-proteins, including Gαo2 and Gαq. Furthermore, glutamate uptake, mediated by vesicular glutamate transporters (VGLUTs), is decreased by the nonhydrolysable GTP-analog guanylylimidodiphosphate. Using mutant mice lacking various Ga subunits, including Gαo1 Gαo2, Gαq, and Gα11, and a Gαo2-Specific monoclonal antibody, we now show that VGLUTs are exclusively regulated by Gαo2. G-protein activation does not affect the electrochemical proton gradient serving as driving force for neurotransmitter uptake; rather, Gαo2 exerts its action by specifically affecting the chloride dependence of VGLUTs. All VGLUTs show maximal activity at ∼5 mM chloride. Activated Gαo2 shifts this maximum to lower chloride concentrations. In contrast, glutamate uptake by vesicles isolated from Gαo2-/- mice have completely lost chloride activation. Thus, Gαo2 acts on a putative regulatory chloride binding domain that appears to modulate transport activity of vesicular glutamate transporters. [ABSTRACT FROM AUTHOR]

Classical neurotransmitters, including monoamines, acetylcholine, glutamate, GABA, and glycine, are loaded into synaptic vesicles by means of specific transporters. Vesicular monoamine transporters are under negative regulation by alpha subunits of trimeric G-proteins, including Galpha(o2) and Galpha(q). Furthermore, glutamate uptake, mediated by vesicular glutamate transporters (VGLUTs), is decreased by the nonhydrolysable GTP-analog guanylylimidodiphosphate. Using mutant mice lacking various Galpha subunits, including Galpha(o1), Galpha(o2), Galpha(q), and Galpha11, and a Galpha(o2)-specific monoclonal antibody, we now show that VGLUTs are exclusively regulated by Galpha(o2). G-protein activation does not affect the electrochemical proton gradient serving as driving force for neurotransmitter uptake; rather, Galpha(o2) exerts its action by specifically affecting the chloride dependence of VGLUTs. All VGLUTs show maximal activity at approximately 5 mm chloride. Activated Galpha(o2) shifts this maximum to lower chloride concentrations. In contrast, glutamate uptake by vesicles isolated from Galpha(o2-/-) mice have completely lost chloride activation. Thus, Galpha(o2) acts on a putative regulatory chloride binding domain that appears to modulate transport activity of vesicular glutamate transporters.