Enhanced fitness of SARS-CoV-2 variant of concern Alpha but not Beta.

Emerging variants of concern (VOCs) are driving the COVID-19 pandemic1,2. Experimental assessments of replication and transmission of major VOCs and progenitors are needed to understand the mechanisms of replication and transmission of VOCs3. Here we show that the spike protein (S) from Alpha (also known as B.1.1.7) and Beta (B.1.351) VOCs had a greater affinity towards the human angiotensin-converting enzyme 2 (ACE2) receptor than that of the progenitor variant S(D614G) in vitro. Progenitor variant virus expressing S(D614G) (wt-S614G) and the Alpha variant showed similar replication kinetics in human nasal airway epithelial cultures, whereas the Beta variant was outcompeted by both. In vivo, competition experiments showed a clear fitness advantage of Alpha over wt-S614G in ferrets and two mouse models-the substitutions in S were major drivers of the fitness advantage. In hamsters, which support high viral replication levels, Alpha and wt-S614G showed similar fitness. By contrast, Beta was outcompeted by Alpha and wt-S614G in hamsters and in mice expressing human ACE2. Our study highlights the importance of using multiple models to characterize fitness of VOCs and demonstrates that Alpha is adapted for replication in the upper respiratory tract and shows enhanced transmission in vivo in restrictive models, whereas Beta does not overcome Alpha or wt-S614G in naive animals.

Pseudotyping vesicular stomatitis virus with lymphocytic choriomeningitis virus glycoproteins enhances infectivity for glioma cells and minimizes neurotropism.

Vesicular stomatitis virus (VSV)-based oncolytic virotherapy has the potential to significantly improve the prognosis of aggressive malignancies such as brain cancer. However, VSV's inherent neurotoxicity has hindered clinical development so far. Given that this neurotropism is attributed to the glycoprotein VSV-G, VSV was pseudotyped with the nonneurotropic envelope glycoprotein of the lymphocytic choriomeningitis virus (LCMV-GP→VSV-GP). Compared to VSV, VSV-GP showed enhanced infectivity for brain cancer cells in vitro while sparing primary human and rat neurons in vitro and in vivo, respectively. In conclusion, VSV-GP has a much wider therapeutic window than VSV and is thus more suitable for clinical applications, especially in the brain.

Quality of Care for Patients With Multiple Sclerosis-A Review of Existing Quality Indicators.

Background: The care of patients with multiple sclerosis (MS) calls for a lifelong guidance and treatment and results in a high resource utilization. Therefore, strategies for the assessment and improvement of the care process are crucial. Quality indicators have become a widely used instrument to determine quality in many areas of the healthcare system. The currently available sets of indicators for the quality of MS care are summarized in this review. Methods: A literature search was conducted for reports that include statements on quality indicators for the care of people with MS. For the determination of the strength of the underlying evidence of the identified publications appropriate criteria of the PRISMA and AGREE-Statements were used. A further prioritization of the eligible indicators was based on the internal grading by the initial authors. Results: Of the 465 included records in the search, 6 sources were finally identified, 3 demonstrating a high and the others a medium strength of evidence. In total, these six reports described 226 quality indicators for the treatment of MS. Of them, 147 were further included in the assessment due to the scope of this article. Among the 101 indicators that originated from reports with a high strength of evidence, 6 also had a high initial internal grading. These six identified quality indicators describe five important characteristics of a high-quality care of MS. Conclusion: The search led to a scientifically evident set of six quality indicators for the assessment of care for patients with MS. These should be seen as starting points in the development of comprehensive sets of quality indicators in MS that addresses the individual objective of their use.

CVnCoV and CV2CoV protect human ACE2 transgenic mice from ancestral B BavPat1 and emerging B.1.351 SARS-CoV-2.

The ongoing SARS-CoV-2 pandemic necessitates the fast development of vaccines. Recently, viral mutants termed variants of concern (VOC) which may escape host immunity have emerged. The efficacy of spike encoding mRNA vaccines (CVnCoV and CV2CoV) against the ancestral strain and the VOC B.1.351 was tested in a K18-hACE2 transgenic mouse model. Naive mice and mice immunized with a formalin-inactivated SARS-CoV-2 preparation were used as controls. mRNA-immunized mice develop elevated SARS-CoV-2 RBD-specific antibody and neutralization titers which are readily detectable, but significantly reduced against VOC B.1.351. The mRNA vaccines fully protect from disease and mortality caused by either viral strain. SARS-CoV-2 remains undetected in swabs, lung, or brain in these groups. Despite lower neutralizing antibody titers compared to the ancestral strain BavPat1, CVnCoV and CV2CoV show complete disease protection against the novel VOC B.1.351 in our studies.

Astrocytic Calcium Waves Signal Brain Injury to Neural Stem and Progenitor Cells.

Brain injuries, such as stroke or trauma, induce neural stem cells in the subventricular zone (SVZ) to a neurogenic response. Very little is known about the molecular cues that signal tissue damage, even over large distances, to the SVZ. Based on our analysis of gene expression patterns in the SVZ, 48 hr after an ischemic lesion caused by middle cerebral artery occlusion, we hypothesized that the presence of an injury might be transmitted by an astrocytic traveling calcium wave rather than by diffusible factors or hypoxia. Using a newly established in vitro system we show that calcium waves induced in an astrocytic monolayer spread to neural stem and progenitor cells and increase their self-renewal as well as migratory behavior. These changes are due to an upregulation of the Notch signaling pathway. This introduces the concept of propagating astrocytic calcium waves transmitting brain injury signals over long distances.

BMP-2 immobilized on nanocrystalline diamond-coated titanium screws; demonstration of osteoinductive properties in irradiated bone.

BACKGROUND: Irradiation results in impaired bone healing. Thus, osteosynthesis procedures are afflicted with increased failure rates. To improve osseointegration bone morphogenetic protein-2 (BMP-2) immobilized on nanocrystalline diamond (NCD)-coated implant surfaces might be 1 solution. METHODS: By 4 weeks after irradiation of pig's mandible with a dose of 60 Gy a fracture was accomplished. Osteosynthesis was performed either with titanium osteosynthesis screws or NCD-coated screws with immobilized BMP-2. Nonirradiated animals served as control. After 1, 2, 4, and 8 weeks screws were evaluated histologically. Bone biopsies were gained to extract mesenchymal stem or precursor cells (MSCs). RESULTS: MSCs after irradiation demonstrated a behavior comparable to that of unirradiated cells. Consequently, immobilized BMP-2 resulted in an initial increased bone contact ratio (p = .014) but demonstrated no sustainable effect compared with osseointegration in nonirradiated bone (p = .08). CONCLUSION: Immobilized BMP-2 demonstrates an osteoinductive effect in irradiated bone. MSCs as effector cells possess protective mechanisms to overcome the destructive effect of irradiation.

Craniomaxillofacial trauma: synopsis of 14,654 cases with 35,129 injuries in 15 years.

Craniomaxillofacial (CMF) trauma occurs in isolation or in combination with other serious injuries, including intracranial, spinal, and upper- and lower-body injuries. It is a major cause of expensive treatment and rehabilitation requirements, temporary or lifelong morbidity, and loss of human productivity. The aim of this study was to evaluate patterns of CMF trauma in a large patient sample within a 15-year time frame. Between 1991 and 2005, CMF trauma data were collected from 14,654 patients with 35,129 injuries at the Department of Cranio-Maxillofacial and Oral Surgery in Innsbruck, assessing a plethora of parameters such as injury type and mechanism as well as age and gender distribution over time. Three main groups of CMF trauma were evaluated: facial bone fractures, dentoalveolar trauma, and soft tissue injuries. Statistical comparisons were carried out using a chi-square test. This was followed by a logistic regression analysis to determine the impact of the five main causes for CMF injury. Older people were more prone to soft tissue lesions with a rising risk of 2.1% per year older, showing no significant difference between male and female patients. Younger patients were at higher risk of suffering from dentoalveolar trauma with an increase of 4.4% per year younger. This number was even higher (by 19.6%) for female patients. The risk of sustaining facial bone fractures increased each year by 4.6%. Male patients had a 66.4% times higher risk of suffering from this type of injury. In addition, 2550 patients (17.4%) suffered from 3834 concomitant injuries of other body parts. In summary, we observed changing patterns of CMF trauma over the last 15 years, paralleled by advances in refined treatment and management options for rehabilitation and reconstruction of patients suffering from CMF trauma.