Comparison of assay methods for quantifying sex hormone concentrations across the menstrual cycle in rhesus macaques†.

Immunoassays have been the preferred method for steroid hormone analysis for more than 50 years. Automated immunoassays (AIAs) offer high throughput, rapid data turnaround, and low cost for measuring steroid hormone concentrations. The application of liquid chromatography-tandem mass spectrometry (LC-MS/MS) for steroid quantification provides greater specificity and selectivity for individual steroids, the ability to simultaneously analyze multiple steroids, and high throughput and automation.

Age-related increase in the expression of 11β-hydroxysteroid dehydrogenase type 1 in the hippocampus of male rhesus macaques.

Introduction: The hippocampus is especially susceptible to age-associated neuronal pathologies, and there is concern that the age-associated rise in cortisol secretion from the adrenal gland may contribute to their etiology. Furthermore, because 11β-hydroxysteroid dehydrogenase type 1 (HSD11B1) catalyzes the reduction of cortisone to the active hormone cortisol, it is plausible that an increase in the expression of this enzyme enhances the deleterious impact of cortisol in the hippocampus and contributes to the neuronal pathologies that underlie cognitive decline in the elderly.

Methods: Rhesus macaques were used as a translational animal model of human aging, to examine age-related changes in gene and protein expressions of (/HSD11B1) in the hippocampus, a region of the brain that plays a crucial role in learning and memory.

Effect of hormone replacement therapy on amyloid beta (Aβ) plaque density in the rhesus macaque amygdala.

Background: Amyloid beta (Aβ) plaque density was examined in the amygdala of rhesus macaques, to elucidate the influence of age, diet and hormonal environment.

Methods: Luminex technology was used to measure cerebrospinal fluid (CSF) concentrations of Aβ and Aβ across three decades, while immunohistochemistry was used to examine Aβ plaque density in the amygdala.

Results: Aβ was found to be the predominant isoform of Aβ in the CSF, but neither Aβ or Aβ concentrations showed an age-related change, and the ratio of Aβ to Aβ showed only a marginal increase.

Pathological Markers of Alzheimer's Disease and Related Dementia in the Rhesus Macaque Amygdala.

Rhesus macaques develop amyloid-β (Aβ) plaques during old age, but it is unclear how extensively they express other pathological hallmarks of dementia. Here we used immunohistochemistry to examine expression of phosphorylated tau (pTau) protein and cytoplasmic inclusions of TAR DNA binding protein 43 kDa (TDP-43) within the amygdala of young and old males, and also in old surgically-menopausal females that were maintained on regular or obesogenic diets. Only one animal, a 23-year-old female, showed pTau expression and none showed TDP-43 inclusions.

Principal component analysis of a swine injury model identifies multiple phenotypes in trauma.

Background: Trauma is the third leading cause of death in the United States and the primary cause of death for people between the ages of 1 year and 44 years. In addition to tissue damage, trauma may also activate an inflammatory state known as trauma-induced coagulopathy (TIC) that is associated with clotting malfunctions, acidemia, and end-organ dysfunction. Prior work has also demonstrated benefit to acknowledging the type and severity of endothelial injury, coagulation derangements, and systemic inflammation in the management of trauma patients.