Neurological symptoms after COVID-19 vaccination: a report on the clinical presentation of the first 50 patients.

OBJECTIVES: Neurological symptoms associated with Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) vaccination were discovered in the context of billions of administered vaccine doses. The clinical manifestations often resemble post Coronavirus Disease 2019 (post-COVID-19) syndrome (PCS) features and may be considered as post-COVID-19 vaccine syndrome (PVS). Data regarding frequency, severity and pathophysiological mechanisms are scarce. METHODS: We assessed routine clinical examinations in 50 patients reporting new-onset neurological symptoms after SARS-CoV-2 vaccination, including neurological examination, laboratory and electrophysiology tests, as well as self-report questionnaires measuring fatigue, depressive symptoms, anxiety, risk of somatic symptom disorder, and health-related quality of life. Patients were included when symptoms occurred after confirmed COVID-19 vaccination and without prior SARS-CoV-2 infection, and if no alternative diagnosis was found to explain the symptoms. RESULTS: The most frequently reported symptoms were paraesthesia (56%), fatigue (46%) and cognitive impairment (36%). Neurological, routine laboratory, and electrophysiological examinations did not yield distinct pathological findings. Neuropsychological testing of a subgroup revealed deficits in attention, executive function and memory. DISCUSSION: The spectrum of clinical manifestations post-vaccination poses a substantial overlap with PCS symptoms. As no pathological findings were obtained in routine diagnostics, uncertainty remains about the underlying pathophysiological mechanisms and requires further investigation beyond routine work-up.

Bacterial Growth, Communication, and Guided Chemotaxis in 3D-Bioprinted Hydrogel Environments.

Bioprinting of engineered bacteria is of great interest for applications of synthetic biology in the context of living biomaterials, but so far, only a few viable approaches are available for the printing of gels hosting live Escherichia coli bacteria. Here, we develop a gentle extrusion-based bioprinting method based on an inexpensive alginate/agarose ink mixture that enables printing of E. coli into three-dimensional hydrogel structures up to 10 mm in height. We first characterize the rheological properties of the gel ink and then study the growth of the bacteria inside printed structures. We show that the maturation of fluorescent proteins deep within the printed structures can be facilitated by the addition of a calcium peroxide-based oxygen generation system. We then utilize the bioprinter to control different types of interactions between bacteria that depend on their spatial position. We next show quorum-sensing-based chemical communication between the engineered sender and receiver bacteria placed at different positions inside the bioprinted structure and finally demonstrate the fabrication of barrier structures defined by nonmotile bacteria that can guide the movement of chemotactic bacteria inside a gel. We anticipate that a combination of 3D bioprinting and synthetic biological approaches will lead to the development of living biomaterials containing engineered bacteria as dynamic functional units.

Scalable Synthesis of Few-Layered 2D Tungsten Diselenide (2H-WSe2) Nanosheets Directly Grown on Tungsten (W) Foil Using Ambient-Pressure Chemical Vapor Deposition for Reversible Li-Ion Storage.

We report a facile two-furnace APCVD synthesis of 2H-WSe2. A systematic study of the process parameters is performed to show the formation of the phase-pure material. Extensive characterization of the bulk and exfoliated material confirm that 2H-WSe2 is layered (i.e., 2D). X-ray diffraction (XRD) confirms the phase, while high-resolution scanning electron microscopy (HRSEM), high-resolution transmission electron microscopy (HRTEM), and atomic force microscopy (AFM) clarify the morphology of the material. Focused ion beam scanning electron microscopy (FIB-SEM) estimates the depth of the 2H-WSe2 formed on W foil to be around 5-8 µm, and Raman/UV-vis measurements prove the quality of the exfoliated 2H-WSe2. Studies on the redox processes of lithium-ion batteries (LiBs) show an increase in capacity up to 500 cycles. On prolonged cycling, the discharge capacity up to the 50th cycle at 250 mA/g of the material shows a stable value of 550 mAh/g. These observations indicate that exfoliated 2H-WSe2 has promising applications as an LiB electrode material.

Titanium dioxide nanoparticle exposure alters metabolic homeostasis in a cell culture model of the intestinal epithelium and Drosophila melanogaster.

Nanosized titanium dioxide (TiO2) is a common additive in food and cosmetic products. The goal of this study was to investigate if TiO2 nanoparticles affect intestinal epithelial tissues, normal intestinal function, or metabolic homeostasis using in vitro and in vivo methods. An in vitro model of intestinal epithelial tissue was created by seeding co-cultures of Caco-2 and HT29-MTX cells on a Transwell permeable support. These experiments were repeated with monolayers that had been cultured with the beneficial commensal bacteria Lactobacillus rhamnosus GG (L. rhamnosus). Glucose uptake and transport in the presence of TiO2 nanoparticles was assessed using fluorescent glucose analog 2-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose (2-NBDG). When the cell monolayers were exposed to physiologically relevant doses of TiO2, a statistically significant reduction in glucose transport was observed. These differences in glucose absorption were eliminated in the presence of beneficial bacteria. The decrease in glucose absorption was caused by damage to intestinal microvilli, which decreased the surface area available for absorption. Damage to microvilli was ameliorated in the presence of L. rhamnosus. Complimentary studies in Drosophila melanogaster showed that TiO2 ingestion resulted in decreased body size and glucose content. The results suggest that TiO2 nanoparticles alter glucose transport across the intestinal epithelium, and that TiO2 nanoparticle ingestion may have physiological consequences.