[Sepsis-associated Purpura Fulminans International Registry--Europe (SAPFIRE)]

BACKGROUND

Purpura fulminans is a rare life-threatening condition which is characterized by disseminated thrombosis in dermal and systemic microcirculation, cutaneous hemorrhages with progressing necrosis and multiple organ failure. The underlying pathogenesis is based on the disruption of the intrinsic anticoagulation cascade, with protein C deficiency being considered the leading factor in this process. In the majority of cases, the condition emerges as consumptive coagulopathy associated with severe sepsis.

OBJECTIVES

Epidemiological data on sepsis-associated purpura fulminans (SAPF) are scarce and evidence-based treatment guidelines have not been established yet. While restoration of the balance in the coagulation cascade is a declared therapeutic goal, evaluations of the efficacy of different therapeutic approaches in randomized clinical trials are still lacking. The causal role of individual microbial pathogens also requires comprehensive evaluation.

METHODS

A prospective multicenter Sepsis-Associated Purpura Fulminans International Registry-Europe (SAPFIRE) will be established in the first quarter of 2015. For the first time, participating centers will systematically collect information on etiology, clinical course, biomarkers, treatment, morbidity, and mortality of SAPF.

RESULTS

The SAPFIRE data will be periodically evaluated and disseminated. Retrospective analysis of each center's data and regular access to aggregated information collected by other centers will enable the participants to monitor and update care quality standards.

Telemetric assessment of referred vaginal hyperalgesia and the effect of indomethacin in a rat model of endometriosis

Symptoms of endometriosis (ENDO), among others, include pelvic/abdominal and muscle pain. Non-steroidal anti-inflammatory agents are first-line treatment for this pain. Similar to women, rats with surgically induced ENDO, but not its surgical control, exhibit vaginal hyperalgesia, which in rats is evidenced by a decreased threshold for the visceromotor response (VMR) induced by vaginal distention. Here we assess the VMR in rats with implanted probes that telemetrically transmit EMG activity from the abdominal muscle. The feasibility and sensitivity of this technique for monitoring the VMR threshold across the estrous cycle and the influence of Indomethacin on ENDO-induced vaginal hyperalgesia were evaluated. VMR thresholds in response to vaginal distention with an infusion pump were measured in different estrous stages. Indomethacin (5 or 10 mg/kg i.p. or s.c.) was injected in proestrus rats and 40-60 min later the VMR threshold was measured. The VMR threshold varied across the estrous cycle only in ENDO rats, being lowest in proestrus. Indomethacin increased this threshold in proestrus ENDO rats. These results show that telemetric assessment of the VMR is a sensitive tool, suitable for long-term studies in conscious rats. The results with this technique also suggest that ENDO-associated vaginal hyperalgesia involves COX activity, the feature that also underlies inflammatory pains.

The role of Eralpha and ERbeta in the prostate: insights from genetic models and isoform-selective ligands

Androgens are known regulators of the growth and differentiation of the prostate gland and are effective during development and maturity as well as in disease. The role of estrogens is less well characterized, but dual direct and indirect actions on prostate growth and differentiation have been demonstrated, facilitated via both ERalpha, and ERbeta. Previous studies using animal models to determine the role of ERbeta in the prostate have been problematic due to the centrally mediated responses to estrogen administration via ERalpha that can lower androgen levels and lead to epithelial regression, thereby masking any direct effects on the prostate mediated by ERbeta. Our alternate approach was to use the estrogen-deficient aromatase knockout (ArKO) mouse and the method of tissue recombination to provide new insight into estrogen action on prostate growth and pathology. Firstly, utilizing homo- and heterotypic tissue recombinants, we demonstrate that stromal aromatase deficiency results in the induction of hyperplasia in previously normal prostatic epithelium and that this response is the result of local changes to the paracrine interaction between stroma and epithelium. Secondly, using tissue recombination and an ERbeta-specific agonist, we demonstrate that the activation of ERbeta results in an anti-proliferative response that is not influenced by alterations to systemic androgen levels or activation of ERalpha. Finally, using intact ArKO mice this study demonstrates that the administration of an ERbeta-specific agonist abrogates existing hyperplastic epithelial pathology specifically in the prostate but an ERbeta-specific agonist does not. Therefore, in the absence of stromal aromatase gene expression, epithelial proliferation, leading to prostatic hypertrophy and hyperplasia, may result from a combination of androgenic stimulation of proliferation and failed activation of ERbeta by locally synthesized estrogens. These data demonstrate essential and beneficial effects of estrogens that are necessary for normal growth of the prostate and distinguish them from those that adversely alter prostate growth and differentiation. This indicates the potential of antiandrogens and SERMS, as opposed to aromatase inhibitors, for the management of prostate hyperplasia and hypertrophy.

17 Alpha-oestradiol and 17 beta-oestradiol do not affect basal and follicle-stimulating hormone-stimulated inhibin B secretion by highly purified rat Sertoli cells

The effects of 17 alpha-oestradiol and 17 beta-oestradiol on basal and follicle-stimulating hormone (FSH)-stimulated inhibin B secretion by rat Sertoli cells were studied. Sertoli cells were isolated and cultivated from testes of 18-day-old Wistar rats in the presence and absence of FSH and different doses of oestrogens. On day 4 of culture, secreted inhibin was measured by enzyme-linked immunosorbent assay. Neither 17 alpha-oestradiol nor 17 beta-oestradiol had any effect on the secreted inhibin level in either the presence or absence of FSH. It is concluded that these oestradiols do not play an essential role in regulatory processes involving inhibin or FSH.

Effect of single and repeated immobilization stress on the heat shock protein 70/90 system of the rat: glucocorticoid-independent, reversible reduction of Hsp90 in the liver and spleen

Heat shock proteins (hsps) and glucocorticoids are produced in response to many common stressors. In addition, hsps interact physically with the intracellular glucocorticoid receptor (GR) and facilitate its activation by the hormone. To study the effect of stress on the hsp70/90 system and the potential association of the system with the hypothalamic-pituitary-adrenal (HPA) axis, we subjected 3 month-old male Harlan-Sprague Dawley rats to single or repeated (once daily for 6 consecutive days) immobilizations, and measured hsp70/90 steady-state levels in a panel of tissues, as well as circulating ACTH and corticosterone concentrations before, during and after immobilization. Single or repeated immobilizations had, as expected, a profound stimulatory effect on the HPA axis but did not influence the steady-state levels of hsp70/90 in any of the gross brain regions (pituitary, hypothalamus, hippocampus or brain cortex) or most peripheral tissues (thymus, adrenal glands, testes) examined. The hsp90 levels, however, were markedly and reversibly decreased in the liver and spleen both by single and repeated immobilizations. The potential inhibitory effect of glucocorticoids on liver and spleen hsp90 was investigated in bilaterally adrenalectomized rats treated with placebo or oral pharmacologic doses of corticosterone for 1 week. Neither adrenalectomy nor corticosterone treatment had an effect on the hsp70/90 system, suggesting that factors other than glucocorticoids mediate the effect of stress on hsp90 concentrations in the liver and spleen. We conclude that acute and chronic stress are associated with a reversible reduction of hsp90 in the liver and spleen, and this appears independent of glucocorticoids.(ABSTRACT TRUNCATED AT 250 WORDS)

Suppression of hypothalamic-pituitary-adrenal axis responsiveness to stress in a rat model of acute cholestasis

Cholestatic patients undergoing surgery have increased mortality and demonstrate clinical features suggestive of adrenal insufficiency. To examine whether cholestasis influences the status of the hypothalamic-pituitary-adrenal axis, we evaluated rats with acute cholestasis caused by bile duct resection (BDR) and sham-operated and unoperated controls. Basal unstressed plasma concentrations of ACTH and corticosterone were similar in BDR and sham-operated and unoperated control rats. However, exposure of BDR rats to saturated ether vapor resulted in significantly less ACTH and corticosterone release in plasma than in the control animals. To understand the mechanism(s) of decreased HPA axis responsiveness to ether stress in cholestasis, we administered corticotropin-releasing factor (CRF) and measured hypothalamic content, mRNA levels and in vitro secretion of CRF and arginine vasopressin (AVP), the two principal secretagogues of ACTH. In BDR animals, ACTH responses to CRF were decreased and hypothalamic content of CRF and CRF mRNA expression in the paraventricular nucleus were decreased by 25 and 37%, respectively. Furthermore, CRF release from hypothalamic explants of BDR rats was 23% less than that of controls. In contrast to CRF, hypothalamic content of AVP was 35% higher, AVP mRNA in the paraventricular nucleus was increased by 6.6-fold, and hypothalamic explant release of AVP was 24% higher in BDR rats than in control animals. Pituitary ACTH contents were similar in BDR and sham resected rats, but higher than unoperated controls. These findings demonstrate that acute cholestasis in the rat is associated with suppression of hypothalamic-pituitary-adrenal axis responsiveness to stress and demonstrate a dissociation between mechanisms of ACTH regulation mediated by CRF and AVP.

Pituitary-adrenal function and hypothalamic beta-endorphin release in vitro following food deprivation

Basal and dexamethasone-suppressed adrenal glucocorticoid secretion and hypothalamic beta-endorphin (BE) release in vitro were investigated in rats deprived of food for 24, 48, 72, and 96 h. Fasting for up to 48 h neither caused significant changes in serum corticosterone levels nor in the suppressive effect of dexamethasone. Food deprivation for 72-96 h resulted in increased basal serum corticosterone, diminished suppression by dexamethasone, and a significant involution of the thymus. Basal in vitro BE release from hypothalamic explants was significantly increased after the first day of food deprivation, and in vitro perifusion with corticotropin-releasing hormone (CRH) failed to enhance BE release further. With continuing food deprivation, basal BE release remained significantly greater than that from hypothalami originating from normally fed control rats. The stimulatory effect of CRH on BE release was only partially restored after 2 days of fasting. The results suggest that food deprivation for more than 2 days increases basal glucocorticoid secretion, and signs of impairment in hypothalamic-pituitary-adrenal regulation become apparent. These findings might be implicated in the pathogenetic mechanisms of endocrine dysregulation in diseases related to caloric reduction.

Melatonin effects on glucocorticoid receptors in rat brain and pituitary: significance in adrenocortical regulation

1. The effects of chronic melatonin treatment on glucocorticoid binding sites in hippocampus, hypothalamus and pituitary were investigated in rats, subjected to long-term manipulation of circulating corticosterone concentrations. 2. Melatonin treatment decreased the affinity of glucocorticoid receptors. 3. The effect of melatonin was apparent in the presence of normal or enhanced systemic corticosterone levels, but not in long-term adrenalectomized animals.

Melatonin effects on thymus steroid receptors in the course of primary antibody responses: significance of circulating glucocorticoid levels

1. The effects of chronic melatonin treatment on antibody production and thymus glucocorticoid and progestin binding sites in the course of primary immune response were investigated in rats subjected to long-term manipulations of circulating glucocorticoid concentrations. 2. The chronic melatonin treatment enhanced the PFC-ability in control and ADX animals and decreased it in the presence of high circulating corticosterone levels. 3. Melatonin treatment increased the affinity and decreased the density of glucocorticoid and progestin receptors in non-immunized animals, while in SRBC-primed rats it was ineffective. 4. The influence of melatonin was apparent when steroid environment was subject of variations: it decreased the affinity of both types of receptors in ADX animals and increased it in immunized rats which have been subjected simultaneously to corticosterone overdose.

Steroid hormone receptors in the thymus: a site of immunomodulatory action of melatonin

1. Melatonin and glucocorticoids are known to affect the immune response in an opposite mode. The probability for an interaction between these hormones in the thymus gland has been investigated in rats following chronic administration of exogenous melatonin and long-term exposure to variable levels of circulating glucocorticoids. 2. Daily melatonin administration was shown to affect the properties of corticosterone and progestin receptors in the thymus in the presence of normal and increased systemic corticosterone concentrations, but not in adrenalectomized animals. 3. In intact rats melatonin caused a marked increase in the affinity and a decrease in the density of thymic receptors for adrenal steroids. Following corticosterone overdosage, simultaneously with melatonin treatment, a decrease in receptor affinity and a relative increase in the number of binding sites was observed. 4. The results suggest that steroid hormone receptors in the thymus might be considered as a target site for the interaction between melatonin and adrenal steroids in the modulation of the immune response.

Phospholipid and glycolipid synthesis in brain structures of Brattleboro rats

The incorporation of labeled precursors in phospholipids and glycolipids was studied in discrete brain areas of rats with innate vasopressin deficiency (Brattleboro, DI) and intact Long Evans animals (LE). Tracer incorporation was found to be reduced in septal, hypothalamic and hippocampal phospholipids, but enhanced in the glycolipid fraction isolated from the hypothalamus and hippocampus of Brattleboro rats. The results indicate that inherited vasopressin deficit seems to be associated with altered lipid synthesis in some brain areas of the Brattleboro rat, suggesting a probability for impaired translation of chemical signals.