Two distinct nanovirus species infecting faba bean in Morocco

Using monoclonal antibodies raised against a Faba bean necrotic yellows virus (FBNYV) isolate from Egypt and a Faba bean necrotic stunt virus (FBNSV) isolate from Ethiopia, a striking serological variability among nanovirus isolates from faba bean in Morocco was revealed. To obtain a better understanding of this nanovirus variability in Morocco, the entire genomes of two serologically contrasting isolates referred to as Mor5 and Mor23 were sequenced. The eight circular ssDNA components, each identified from Mor5- and Mor23-infected tissues and thought to form the complete nanovirus genome, ranged in size from 952 to 1,005 nt for Mor5 and from 980 to 1,004 nt for Mor23 and were structurally similar to previously described nanovirus DNAs. However, Mor5 and Mor23 differed from each other in overall nucleotide and amino acid sequences by 25 and 26%, respectively. Mor23 was most closely related to typical FBNYV isolates described earlier from Egypt and Syria, with which it shared a mean amino acid sequence identity of about 94%. On the other hand, Mor5 most closely resembled a FBNSV isolate from Ethiopia, with which it shared a mean amino acid sequence identity of approximately 89%. The serological and genetic differences observed for Mor5 and Mor23 were comparable to those observed earlier for FBNYV, FBNSV, and Milk vetch dwarf virus. Following the guidelines on nanovirus species demarcation, this suggests that Mor23 and Mor5 represent isolates of FBNYV and FBNSV, respectively. This is the first report not only on the presence of FBNSV in a country other than Ethiopia but also on the occurrence and complete genome sequences of members of two nanovirus species in the same country, thus providing evidence for faba bean crops being infected by members of two distinct nanovirus species in a restricted geographic area

Post hoc immunostaining of GABAergic neuronal subtypes following in vivo two-photon calcium imaging in mouse neocortex

GABAergic neurons in the neocortex are diverse with regard to morphology, physiology, and axonal targeting pattern, indicating functional specializations within the cortical microcircuitry. Little information is available, however, about functional properties of distinct subtypes of GABAergic neurons in the intact brain. Here, we combined in vivo two-photon calcium imaging in supragranular layers of the mouse neocortex with post hoc immunohistochemistry against the three calcium-binding proteins parvalbumin, calretinin, and calbindin in order to assign subtype marker profiles to neuronal activity. Following coronal sectioning of fixed brains, we matched cells in corresponding volumes of image stacks acquired in vivo and in fixed brain slices. In GAD67-GFP mice, more than 95% of the GABAergic cells could be unambiguously matched, even in large volumes comprising more than a thousand interneurons. Triple immunostaining revealed a depth-dependent distribution of interneuron subtypes with increasing abundance of PV-positive neurons with depth. Most importantly, the triple-labeling approach was compatible with previous in vivo calcium imaging following bulk loading of Oregon Green 488 BAPTA-1, which allowed us to classify spontaneous calcium transients recorded in vivo according to the neurochemically defined GABAergic subtypes. Moreover, we demonstrate that post hoc immunostaining can also be applied to wild-type mice expressing the genetically encoded calcium indicator Yellow Cameleon 3.60 in cortical neurons. Our approach is a general and flexible method to distinguish GABAergic subtypes in cell populations previously imaged in the living animal. It should thus facilitate dissecting the functional roles of these subtypes in neural circuitry

Rab18 and a Rab18 GEF complex are required for normal ER structure

The ancestral Rab GTPase Rab18 and both subunits of the Rab3GAP complex are mutated in the human neurological and developmental disorder Warburg Micro syndrome. Here, we demonstrate that the Rab3GAP complex is a specific Rab18 guanine nucleotide exchange factor (GEF). The Rab3GAP complex localizes to the endoplasmic reticulum (ER) and is necessary for ER targeting of Rab18. It is also sufficient to promote membrane recruitment of Rab18. Disease-associated point mutations of conserved residues in either the Rab3GAP1 (T18P and E24V) or Rab3GAP2 (R426C) subunits result in loss of the Rab18 GEF and membrane-targeting activities. Supporting the view that Rab18 activity is important for ER structure, in the absence of either Rab3GAP subunit or Rab18 function, ER tubular networks marked by reticulon 4 were disrupted, and ER sheets defined by CLIMP-63 spread out into the cell periphery. Micro syndrome is therefore a disease characterized by direct loss of Rab18 function or loss of Rab18 activation at the ER by its GEF Rab3GAP

TIP - Training intensivmedizinischer Unterstützung im Pandemie-Fall

The COVID-19 pandemic has led to a short-term sharp increase in the demand for auxiliary staff in emergency rooms and intensive care units. Against this background student tutors of the Medical Faculty Erlangen have developed a training concept. The aim was to familiarize students in the clinical section quickly and effectively with skills that are particularly important in a clinical assignment as (student) assistant in the care of corona patients (e.g.: personal protective equipment, intubation assistance, arterial blood collection, assessment of blood gas values and ventilation parameters). In a blended learning concept, learning materials were prepared in advance and then implemented and deepened in a presence phase. The selection of learning materials and the low supervision ratio (1:2) made it possible to realize an internally differentiated approach. The offer met with great interest among students of all clinical semesters and was evaluated very positively. The skills learned can be applied widely even independently of a pandemic.Die COVID-19-Pandemie hat zu einem kurzfristig stark erhöhten Bedarf an Hilfskräften in Notaufnahmen und auf Intensivstationen geführt. Vor diesem Hintergrund haben studentische TutorInnen der Medizinischen Fakultät Erlangen ein Schulungskonzept entwickelt. Ziel war es, Studierende im klinischen Abschnitt schnell und effektiv mit Fertigkeiten vertraut zu machen, die in einem klinischen Einsatz als (studentische) Hilfskraft bei der Betreuung von Corona-Patienten besonders wichtig sind (z.B.: persönliche Schutzausrüstung, Intubationsassistenz, arterielle Blutentnahme, Beurteilung von Blutgaswerten und Beatmungsparametern). In einem Blended Learning-Konzept wurden Lernmaterialien vorab bearbeitet und in einer Präsenzphase praktisch umgesetzt und vertieft. Durch die Auswahl der Lernmaterialien und den niedrigen Betreuungsschlüssel (1:2) konnte ein binnendifferenzierter Ansatz realisiert werden. Das Angebot stieß auf großes Interesse bei den Studierenden aller klinischen Semester und wurde sehr positiv evaluiert. Die erlernten Fertigkeiten sind auch unabhängig von einer Pandemie breit einsetzbar

Laboratory Diagnosis of Radicular and Pseudoradicular Syndromes in Cerebrospinal Fluid (CSF)

Laboratory tests may be used to confirm the clinical differentiation of pseudoradicular syndromes and radicular syndromes. In the presence of pseudoradicular syndromes, CSF and blood samples yield no positive results with either non-specific or specific methods. Radicular syndromes give rise to positive findings; using nonspecific methods they can be subdivided into inflammatory and non-inflammatory forms, with and without bloodnefve barrier impairment. Non-specific quantities of CSF routine diagnosis are total protein, albumin, leukocyte counts and differential cell courit, L-lactate, intrathecal -IgG, -IgA, -IgM and immunoglobulin-class oligoclonal bands. Oligoclonal bands enable the highly sensitive differentiation of non-inflammatory firom subacute-chronically inflammatory forms of radicular syndromes. Most of the specific quantities are the subject of current research, e. g. bacterial antigens, D-lactate, cultivation tests, polymerase chain reaction tests and pathogen-specific oligoclonal bands. Pathomechanisms affecting the permeability of the blood-nerve barrier to increasing concentrations of protein and to leukocyte subsets possibly explain the CSF fmdings in radicular and pseudoradicular syndromes.Peer Reviewe