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laevis via dorsal lymph sac injection of gonadotropic hormones and the stimulation of egg laying through application of gentle pressure to the females.The embryos of the African clawed frog, Xenopus laevis, are a powerful substrate for the study of complex fundamental biological and disease mechanisms in neurobiology, physiology, molecular biology, cell biology, and developmental biology. A simple and straightforward technique for generating a large number of developmentally synchronized embryos is in vitro fertilization (IVF). IVF permits simultaneous fertilization of thousands of eggs but requires the death of the parental male, which may not be feasible if the male comes from a stock of precious animals. An alternative to euthanizing a precious male is to use a natural mating, which allows for the collection of many embryos with minimal preparation but with the potential loss of the experimental advantage of developmental synchronization. Here we present both strategies for obtaining X. laevis embryos.The cytoskeleton is a dynamic, fundamental network that not only provides mechanical strength to maintain a cell's shape but also controls critical events like cell division, polarity, and movement. Thus, how the cytoskeleton is organized and dynamically regulated is critical to our understanding of countless processes. Live imaging of fluorophore-tagged cytoskeletal proteins allows us to monitor the dynamic nature of cytoskeleton components in embryonic cells. Here, we describe a protocol to monitor and analyze cytoskeletal dynamics in primary embryonic neuronal growth cones and neural crest cells obtained from Xenopus laevis embryos.Obtaining high quantities of a specific protein directly from native sources is often challenging, particularly when dealing with human proteins. To overcome this obstacle, many researchers take advantage of heterologous expression systems by cloning genes into artificial vectors designed to operate within easily cultured cells, such as Escherichia coli, Pichia pastoris (yeast), and several varieties of insect and mammalian cells. Heterologous expression systems also allow for easy modification of the protein to optimize expression, mutational analysis of specific sites within the protein and facilitate their purification with engineered affinity tags. Some degree of purification of the target protein is usually required for functional analysis. Purification to near homogeneity is essential for characterization of protein structure by X-ray crystallography or nuclear magnetic resonance (NMR) and characterization of the biochemical and biophysical properties of a protein, because contaminating proteins almost always adversely affect the results. Methods for producing and purifying proteins in several different expression platforms and using a variety of vectors are introduced here.In teaching, the best exam questions are those that seem simple at first but can lead to deep and nuanced conversations. Similarly, to probe brain development, we should look for behaviors that are easy to evoke and quantify, but that are demanding, malleable, and inherently variable. Visual collision avoidance is an example of such a behavior; it is ecologically relevant, robust, and easy to record, but also nuanced and shaped by the sensory history of the animal. Here we describe how to set up a visual avoidance assay and how to use it to test sensory processing and sensorimotor transformations in the vertebrate brain.Speech signals have a unique shape of long-term modulation spectrum that is distinct from environmental noise, music, and non-speech vocalizations. Does the human auditory system adapt to the speech long-term modulation spectrum and efficiently extract critical information from speech signals? To answer this question, we tested whether neural responses to speech signals can be captured by specific modulation spectra of non-speech acoustic stimuli. We generated amplitude modulated (AM) noise with the speech modulation spectrum and 1/f modulation spectra of different exponents to imitate temporal dynamics of different natural sounds. We presented these AM stimuli and a 10-min piece of natural speech to 19 human participants undergoing electroencephalography (EEG) recording. We derived temporal response functions (TRFs) to the AM stimuli of different spectrum shapes and found distinct neural dynamics for each type of TRFs. We then used the TRFs of AM stimuli to predict neural responses to the speech signals, and found that (1) the TRFs of AM modulation spectra of exponents 1, 1.5, and 2 preferably captured EEG responses to speech signals in the δ band and (2) the θ neural band of speech neural responses can be captured by the AM stimuli of an exponent of 0.75. Our results suggest that the human auditory system shows specificity to the long-term modulation spectrum and is equipped with characteristic neural algorithms tailored to extract critical acoustic information from speech signals.Although the literature is limited, early evidence suggests that patients with chronic kidney disease, end-stage kidney disease, and kidney transplant recipients are at increased risk for severe COVID-19 disease and death. Hence, management should focus on both infection prevention and treatment. selleck products There is currently a lack of evidence and guideline recommendations on optimal management of immunosuppression in kidney transplant recipients with COVID-19 infection. This article focuses on the prevention and management of COVID-19 in patients with chronic kidney disease, patients with end-stage kidney disease on home hemodialysis and peritoneal dialysis, and kidney transplant recipients.

Patients with CKD who are on hemodialysis are hyporesponsive to erythropoiesis-stimulating agents (ESAs) because of anemia of inflammation. Interleukin-6 (IL-6) induced hepcidin expression is a key mediator of such inflammation.

This phase 1/2, placebo-controlled trial assessed effects of ziltivekimab, a novel anti-IL-6 ligand antibody, in patients on hemodialysis with rs855791, a single nucleotide polymorphism of the

gene that is hypothesized to heighten susceptibility to IL-6-mediated inflammatory effects. After a screening period documenting stable ESA and iron dosing, we randomized 61 patients with elevated IL-6 (≥4 pg/ml) to receive placebo or ziltivekimab (doses of 2, 6, or 20 mg), administered intravenously every 2 weeks for 12 weeks during hemodialysis. ESA dose adjustments were allowed after 4 weeks. We analyzed safety and effects on inflammation, iron metabolism, serum albumin, and anti-drug antibodies.

No patient experienced dose-limiting toxicity. Four patients (two each in the 6- and 20-mg cohorts) died of a treatment-emergent adverse event.