Neuroprotective role of insulin-like growth factor 1 in auditory and other nervous systems

Insulin-like growth factor 1 (IGF1) exerts an influence on almost every organ system in the body and plays an important role in growth, development, and metabolism. In the nervous system, IGF1 acts by promoting the development and growth of neurons and glial cells, differentiation of Schwann cells and their migration to axons, neurite outgrowth, and neuronal survival. The lack of IGF1 is associated with several pathological conditions, including severe prenatal growth retardation, postnatal growth failure, microcephaly, mental retardation, and bilateral sensorineural hearing loss. In addition to its physiological effects, based on the findings of in vivo and in vitro experiments and clinical trials, IGF1 is considered to play a potential role in the treatment of various types of neuronal damage. In this review, we discuss the potential use of IGF1 as a therapeutic molecule in the nervous system: (1) auditory system, including hair cells, cochlear ribbon synapses, auditory nerve, and central nervous systems, and (2) other peripheral nervous systems, especially the olfactory system and facial nerve. The role of IGF1 in the progression of age-related sensory deficits, especially hearing loss and olfactory dysfunction, is also discussed. Recent studies on IGF1 demonstrated that exogenous IGF1 can be applied in many fields, thus supporting the continued evaluation of IGF1 as a potential therapeutic molecule. Additional scientific investigations should be conducted to further supplement recent findings

Three-Dimensional Vascular Architecture of the Dog Heart as Revealed by Injection Replica Scanning Electron Microscopy

The three-dimensional vascular architecture of the dog myocardium was investigated by means of injection replica scanning electron microscopy. Coronary arteries entered into myocardial wall at almost right angle. They repeated bicornal divisions and run toward endocardium. The arterioles and precapillary arterioles branched in bicornal, tricornal or multicornal fashions. These branches were arranged usually in a plane in short distances. Capillaries were arranged parallel to the myocardial cells and had many anastomotic channels. The branching of the capillaries was usually Y-, T-, H- or K-shape, and Y-shape was the most common. Many anastomotic channels between precapillary arterioles were recognized just under the endocardiurn, while same connections were very difficult to identify in the myocardial wall. Numerous venous capillaries joined together with postcapillary venules and collecting venules almost exclusively in a plane parallel to the capillary sheets. Junctional architecture of these capillaries and venules was usually fan-shaped, finger-shaped or feather-shaped in appearance. The postcapillary venules and collecting venules were oriented usually perpendicular to the muscle fiber or capillary direction. The orifices of Thebesian veins, arterio-luminal vessels and arterio-sinusoidal vessels were observed between ventricular trabeculae as small masses of injected resin. The number of these orifices were more abundant in the right ventricular wall than in the left

Ultrafast spatiotemporal photocarrier dynamics near GaN surfaces studied by terahertz emission spectroscopy

Gallium nitride (GaN) is a promising wide-bandgap semiconductor, and new characterization tools are needed to study its local crystallinity, carrier dynamics, and doping effects. Terahertz (THz) emission spectroscopy (TES) is an emerging experimental technique that can probe the ultrafast carrier dynamics in optically excited semiconductors. In this work, the carrier dynamics and THz emission mechanisms of GaN were examined in unintentionally doped n-type, Si-doped n-type, and Mg-doped p-type GaN films. The photocarriers excited near the surface travel from the excited-area in an ultrafast manner and generate THz radiation in accordance with the time derivative of the surge drift current. The polarity of the THz amplitude can be used to determine the majority carrier type in GaN films through a non-contact and non-destructive method. Unique THz emission excited by photon energies less than the bandgap was also observed in the p-type GaN film

Necessary conditions for strong hyperbolicity of first order systems

Because women’s studies radically challenges social hierarchies and lacks a unified identity and canon of thought, it often negotiates a precarious position within the modern corporatized university. At the same time, women’s studies offers—by virtue of its interdisciplinary, critical, and “infectious” structure—cutting-edge perspectives and goals that set it apart from more traditional fields. This paper theorizes that one future pedagogical priority of women’s studies is to train students not only to master a body of knowledge but also to serve as symbolic “viruses” that infect, unsettle, and disrupt traditional and entrenched fields. In this essay, we first posit how the metaphor of the virus in part exemplifies an ideal feminist pedagogy, and we then investigate how both women’s studies and the spread of actual viruses (e.g., Ebola, HIV) produce similar kinds of emotional responses in others. By looking at triviality, mockery, panic, and anger that women’s studies as a field elicits, we conclude by outlining the stakes of framing women’s studies as an infectious, insurrectional, and potentially dangerous, field of study. In doing so, we frame two new priorities for women’s studies—training male students as viruses and embracing “negative” stereotypes of feminist professors—as important future directions for the potentially liberatory aspects of the field

Quantitative PCR assays to detect whales, rockfish, and common murre environmental DNA in marine water samples of the Northeastern Pacific

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Andruszkiewicz, E. A., Yamahara, K. M., Closek, C. J., & Boehm, A. B. Quantitative PCR assays to detect whales, rockfish, and common murre environmental DNA in marine water samples of the Northeastern Pacific. Plos One, 15(12), (2020): e0242689, doi:10.1371/journal.pone.0242689.Monitoring aquatic species by identification of environmental DNA (eDNA) is becoming more common. To obtain quantitative eDNA datasets for individual species, organism-specific quantitative PCR (qPCR) assays are required. Here, we present detailed methodology of qPCR assay design and testing, including in silico, in vitro, and in vivo testing, and comment on the challenges associated with assay design and performance. We use the presented methodology to design assays for three important marine organisms common in the California Current Ecosystem (CCE): humpback whale (Megaptera novaeangliae), shortbelly rockfish (Sebastes jordani), and common murre (Uria aalge). All three assays have excellent sensitivity and high efficiencies ranging from 92% to 99%. However, specificities of the assays varied from species-specific in the case of common murre, genus-specific for the shortbelly rockfish assay, and broadly whale-specific for the humpback whale assay, which cross-amplified with other two other whale species, including one in a different family. All assays detected their associated targets in complex environmental water samples.This work is a contribution to the Marine Biodiversity Observation Network (MBON). The MBON project was supported by NASA grant NNX14AP62A ‘National Marine Sanctuaries as Sentinel Sites for a Demonstration Marine Biodiversity Observation Network (MBON)’ funded under the National Ocean Partnership Program (NOPP RFP NOAA-NOS-IOOS-2014-2003803 in partnership between NOAA, BOEM, and NASA), and the U.S. Integrated Ocean Observing System (IOOS) Program Office