direct-visualization-murine-dorsal-cochlear-nucleus-for-optogenetic

Direct Visualization of the Murine Dorsal Cochlear Nucleus for Optogenetic Stimulation of the Auditory Pathway

Investigation into the use of virus-mediated gene transfer to arrest or reverse hearing loss has largely been relegated to the peripheral auditory system. ...

Harvard Medical School

To assess iron deficiency (ID) in international adoptees after adoption.

Iron deficiency in international adoptees from Eastern Europe.

The developing limbic-hypothalamic-pituitary-adrenal (LHPA) axis is highly vulnerable to programming by early-life environmental factors, including exposure to synthetic glucocorticoids and nutrient deficiencies. Early-life repetitive hypoglycemia (RHG) is a common complication of insulin therapy for type-1 diabetes that may have long-term consequences in adulthood. Recent observations in a rat model of early RHG suggest persistent changes in LHPA axis function, including changes in relevant hormones and affective behaviors, which support a hyperresponsive LHPA axis. Thus, we hypothesized that early RHG would alter the expression of key genes regulating LHPA axis function in adulthood. The present study employed a rat model of insulin-induced RHG spanning postnatal days (P)24-28, a neurodevelopmental equivalent of early childhood in humans, to assess the long-term effects on mRNA levels for proteins relevant to the LHPA function and the corticosterone responses to ACTH stimulation of dispersed adrenocortical cells in vitro and restraint stress in vivo at adulthood. This early RHG model resulted in a hyporesponsive LHPA axis characterized by impaired corticosterone response, increased hippocampal glucocorticoid and mineralocorticoid receptor (GR and MR), decreased hypothalamic corticotropin-releasing hormone, increased adrenal steroidogenic-acute-regulatory protein and GR, and decreased adrenal MR, melanocortin-type-2 receptor and low-density lipoprotein receptor expression. Our findings highlight a complex environmental-gene interaction between RHG and LHPA axis during development that influences regulation of this axis in adulthood. The findings are consistent with the developmental origins of disease and underscore the influences of early-life events on the programming of a major regulatory system.

Evidence for a hyporesponsive limbic-hypothalamic-pituitary-adrenal axis following early-life repetitive hypoglycemia in adult male rats.

Middle ear surgery increasingly employs endoscopes as an adjunct to or replacement for the operative microscope. We provide a systematic review of endoscope applications in middle ear surgery with an emphasis on outcomes, including the need for conversion to microscope, audiometric findings, length of follow-up, as well as disease-specific outcomes.

Article	Year
Iron deficiency in international adoptees from Eastern Europe. The Journal of pediatrics\| PubMed ID: 18534235	2008
Evidence for a hyporesponsive limbic-hypothalamic-pituitary-adrenal axis following early-life repetitive hypoglycemia in adult male rats. American journal of physiology. Regulatory, integrative and comparative physiology\| PubMed ID: 21593429	2011
Systematic review of outcomes following observational and operative endoscopic middle ear surgery. The Laryngoscope\| PubMed ID: 25418475	2014

Ashton E. Lehmann

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