Men show an age-related decline in the circulating levels of testosterone (T) and dehydroepiandrosterone sulfate (DHEAS). Consequently, there is interest in developing androgen supplementation paradigms for old men that replicate the hormone profiles of young adults. In the present study, we used old (21-26 years old) male rhesus monkeys as a model to examine the efficacy of an androgen supplementation paradigm that comprised oral T administration (12 mg/kg body weight, dissolved in sesame oil/chocolate) in the evening, and two oral DHEA administrations, 3 hr apart (0.04 mg/kg body weight, dissolved in sesame oil/chocolate) in the morning. After 5 days of repeated hormone supplementation, serial blood samples were remotely collected from each animal hourly across the 24-hr day, and assayed for cortisol, DHEAS, T, 5α-dihydrotestosterone (DHT), estrone (E1), and 17β-estradiol (E2). Following androgen supplementation, T levels were significantly elevated and this was associated with a more sustained nocturnal elevation of T's primary bioactive metabolites, DHT and E1 and E2. Plasma DHEAS levels were also significantly elevated after androgen supplementation; DHEAS levels rose in the early morning and gradually declined during the course of the day, closely mimicking the profiles observed in young adults (7-12 years old); in contrast, cortisol levels were unaltered by the supplementation. Together the data demonstrate a non-invasive androgen supplementation paradigm that restores youthful circulating androgen levels in old male primates. Because this paradigm preserves the natural circulating circadian hormone patterns, we predict that it will produce fewer adverse side effects, such as perturbed sleep or cognitive impairment.
Circulating levels of dehydroepiandrosterone, a major adrenal steroid, show a marked age-related decrease in both humans and nonhuman primates. Because this decrease has been implicated in age-related cognitive decline, we administered supplementary dehydroepiandrosterone to perimenopausal rhesus macaques (Macaca mulatta) to test for cognitive benefits. Although recognition memory improved, there was no benefit to spatial working memory. To address the limitations of this study we developed a hormone supplementation regimen in aged male macaques that more accurately replicates the 24-hr androgen profiles of young animals. We hypothesize that this more comprehensive physiological hormone replacement paradigm will enhance cognitive function in the elderly.
Im Laufe der letzten 25 Jahre sind eine Anzahl Eiterung erregender Mikroorganismen entdeckt und besehrieben worden. Von diesen kommen einige h~ufiger, andere seltener zur Beobaehtuug. Zu letzteren gehGrt der Strahlenpilz. Unsere Kenntnisse Uber die Aktinomyeose verdanken wir haupt-s~ehlieh den Arbeiten yon Bollinger, J. Israel, Ponfick, Wolff, Bostroem und vielen anderen. Ausser der Infection mit dem typischen Strahlenpilz kommen nun hin und wieder chronische Eiterungen vor, welehe k[inisch mit dem Verlauf der Aktinomycose nahezu Ubereinstimmen, aber nieht dureh den yon James Israel oder Bostroem beschriebenen Aktinomycespilz erzeugt worden sind, sondern dutch eng ver~vandte Baeterienarten. Hierher gehGrt die yon Hesse in der Deutsehen Zeitsehrift fiir Chirurgie 1892, Bd. 34 beschriebene und als Cladothrix liquefaeiens bezeiehnete Bacterienart und die, welehe ieh in folgenden Zeilen kurz sehildern will. Zun~chst die Krankengeschichte. Der 22 Jahre alte Schlosser K. H. aus Leipzig warde am 3. December 1892 nach der chirurgischen Abtheilung des st~idtischen Krankenhauses zu St. Jacob in Leipzig" aufg"enommen. Der Beginn seiner Krankheit geht auf Februar 1890 zurtiek. In dieser Zeit klag"te er fiber anhaltende allgemeine Brustsehmerzen und zeitweise auftretendes hef'tiges Steehen in der Brust. Dieses stellte sieh zumeist dann ein~ wenn er l~ingere Zeit gegangen war~ und zwar so stark, dass er nur mit grossen Besehwerden und Schmerzen athmen konnte. Fast ffleiehzeitig traten auch Sehmerzen im Rtieken auf, reehts neben dem Kreuz. Diese versehwanden bald, kehrten aber naeh kurzer Zeit etwas st~trker wieder und so wechselnd, abet immer sieh steigernd bis Deutscho Zoits~hrift f. Chirurgio. X_[~I. Bcl.
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