HB-EGF and EGF infusion following CNS demyelination mitigates age-related decline in regeneration of oligodendrocytes from neural precursor cells originating in the ventricular-subventricular zone

In multiple sclerosis (MS), chronic demyelination initiated by immune-mediated destruction of myelin, leads to axonal damage and neuronal cell death, resulting in a progressive decline in neurological function. The development of interventions that potentiate remyelination could hold promise as a novel treatment strategy for MS. To this end, our group has demonstrated that neural precursor cells (NPCs) residing in the ventricular-subventricular zone (V-SVZ) of the adult mouse brain contribute significantly to remyelination in response to central nervous system (CNS) demyelination and can regenerate myelin of normal thickness. However, aging takes its toll on the regenerative potential of NPCs and reduces their contribution to remyelination. In this study, we investigated how aging influences the contribution of NPCs to oligodendrogenesis during the remyelination process and whether the delivery of growth factors into the brains of aged mice could potentiate the oligodendrogenic potential of NPCs. To enable us to map the fate of NPCs in response to demyelination induced at different postnatal ages, Nestin-CreERT2;Rosa26-LSL-eYFP mice were gavaged with tamoxifen at either 8 weeks, 30 weeks or one year of age before being challenged with cuprizone for a period of six weeks. Using osmotic minipumps, we infused heparin-binding EGF-like growth factor (HB-EGF), and/or epidermal growth factor (EGF) into the cisterna magna for a period of two weeks beginning at the peak of cuprizone-induced demyelination (n=6-8 mice per group). Control mice received artificial cerebrospinal fluid (vehicle) alone. Mice were perfused six weeks after cuprizone withdrawal and the contribution of NPCs to oligodendrocyte regeneration in the corpus callosum was assessed. Our data reveal that although NPC-derived oligodendrocyte generation declined dramatically with age, this decline was partially reversed by growth factor infusion. Notably, co-infusion of EGF and HB-EGF increased oligodendrocyte regeneration twofold in some regions of the corpus callosum. Our results shed light on the beneficial effects of EGF and HB-EGF for increasing the contribution of NPCs to remyelination and indicate their therapeutic potential to combat the negative effects of aging upon remyelination efficacy.

The impact of physical activity and group discussion on happiness in postmenopausal women: A randomized trial

Menopause is a physiological phenomenon, which in some cases may lead to physical and psychological complications. These complications degrade happiness and quality of life. The authors conducted the current study to determine the impact of physical activity (PA) and group discussion (GD) on happiness in postmenopausal women. For this clinical trial with a factorial design, 160 eligible menopausal women in the 45-55 age range were randomly assigned to four groups of PA, GD and GD+PA), and control group. The four groups completed the Oxford Happiness Questionnaire. The happiness score in the PA, GD and GD+PA groups was significantly higher immediately and two months after the intervention than that of the control group. PA and GD can increase happiness in postmenopausal women who reside in Kermanshah-Iran. Using PA and GD in postmenopausal women care programs is recommended.

High-efficiency pharmacogenetic ablation of oligodendrocyte progenitor cells in the adult mouse CNS

Approaches to investigate adult oligodendrocyte progenitor cells (OPCs) by targeted cell ablation in the rodent CNS have limitations in the extent and duration of OPC depletion. We have developed a pharmacogenetic approach for conditional OPC ablation, eliminating >98% of OPCs throughout the brain. By combining recombinase-based transgenic and viral strategies for targeting OPCs and ventricular-subventricular zone (V-SVZ)-derived neural precursor cells (NPCs), we found that new PDGFRA-expressing cells born in the V-SVZ repopulated the OPC-deficient brain starting 12 days after OPC ablation. Our data reveal that OPC depletion induces V-SVZ-derived NPCs to generate vast numbers of PDGFRA+NG2+ cells with the capacity to proliferate and migrate extensively throughout the dorsal anterior forebrain. Further application of this approach to ablate OPCs will advance knowledge of the function of both OPCs and oligodendrogenic NPCs in health and disease.

Design and finite element modeling of two-dimensional nanomechanical biosensors for SARS-CoV-2 detection

SARS-CoV-2 is the causative agent of COVID-19 disease. The development of different variants has increased the prevalence, pathogenicity, and mortality of the SARS-CoV-2. Prompt diagnosis and timely initiation of therapy can undoubtedly minimize the damage caused by this virus. In this study, a wide range of emerging single layer two-dimensional materials (SL2DMs), including graphene, grapheme oxide (GO), reduced graphene oxide (rGO), hexagonal boron nitride (h-BN), Ti3C2Tx MXene, and MoS2that can be used to fabricate highly sensitive biosensors, are analyzed using the finite element method based on antigen-antibody interaction. Important design parameters including sensor size, sensor aspect ratio, number of viruses, and applying in-plane strain on sensor performance are analyzed using frequency shift technique. In the following, an analytical relationship that can predict the limit of detection (LOD) according to the above parameters is proposed. The results show that all the above materials have a good performance in detecting viruses in the sample range of 10-100 viruses. This range can be reduced significantly by applying strains of less than 0.1. Also, applying strain increases shift frequency index by 2 to 3 times, which is a significant result. The maximum and minimum sensor performance are obtained for GO and Ti3C2Tx, respectively. The results of this paper can be used to build a new generation of two-dimensional biosensors for rapid detection of COVID-19 and other viruses.

[Position Paper of the Youth Forum DGOU 2010 - part 1]

The aim of the "Youth Forum of the DGOU" during the Convention 2010 in Heidelberg was to place a statement concerning the professional politics in the field of Orthopaedic and Trauma Surgery. The emigration of young German physicians, the occupational image of the Physician Assistant and the quality of the German residency programs in Orthopaedic and Trauma Surgery we discussed as main topics. The main reason for young German physicians to go abroad is, besides better work conditions and less bureaucracy, the better structured education during residency. Therefore the "Youth Forum" generally supports the concept of the "physician assistant" as "a relief from non-physician duties rather than discussing the delegation of true physician duties". The "Youth Forum" is looking forward to collaborating on the improvement of the ongoing education of residents. In this regard, Orthopaedic and Trauma Surgery needs to become more attractive for young academics. We also support a uniform and nationwide curriculum, which guarantees a structured education to improve the theoretic, practical and academic skills of the future specialist in orthopaedic and trauma surgery. Additional surveys and interviews among the current generation of residents are needed to further specify the potential goals of such a curriculum. We would like to discuss the future of our speciality with our colleagues. Therefore different communication platforms including our website http://www.jf-dgou.de have been created.