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The Comet Physics Laboratory (CoPhyLab) is an international research program to study the physical properties of cometary analog materials under simulated space conditions. The project is dedicated to studying, with the help of multiple instruments and the different expertise and background from the different partners, the physics of comets, including the processes inside cometary nuclei, the activity leading to the ejection of dust and gas, and the sub-surface and surface evolution of cometary nuclei when exposed to solar illumination. CoPhyLab will provide essential information on the formation and evolution of comets and insights into the origins of primitive Solar System bodies. To this end, we constructed a new laboratory that hosts several small-scale experiments and a large-scale comet-simulation chamber (L-Chamber). This chamber has been designed and constructed to host ice-dust samples with a diameter of up to 250 mm and a variable height between 100 and 300 mm. The cometary-analog samples will be kept at temperatures below 120 K and pressures around 10 -6 mbar to ensure cometary-like conditions. In total, 14 different scientific instruments are attached to the L-Chamber to study the temporal evolution of the physical properties of the sample under different insolation conditions. Due to the implementation of a scale inside the L-Chamber that can measure weight changes of the samples with high precision, the cooling system is mechanically decoupled from the sample holder and cooling of the samples occurs by radiation only. The constructed chamber allows us to conduct uninterrupted experiments at low temperatures and pressures up to several weeks.

Background: To compare the clinical efficacy of New York Esophageal squamous cell carcinoma-1 (NY-ESO-1) vaccine with ISCOMATRIX adjuvant versus ISCOMATRIX alone in a randomized, double-blind phase II study in participants with fully resected melanoma at high risk of recurrence., Methods: Participants with resected stage IIc, IIIb, IIIc and IV melanoma expressing NY-ESO-1 were randomized to treatment with three doses of NY-ESO-1/ISCOMATRIX or ISCOMATRIX adjuvant administered intramuscularly at 4-week intervals, followed by a further dose at 6 months. Primary endpoint was the proportion free of relapse at 18 months in the intention-to-treat (ITT) population and two per-protocol populations. Secondary endpoints included relapse-free survival (RFS) and overall survival (OS), safety and NY-ESO-1 immunity., Results: The ITT population comprised 110 participants, with 56 randomized to NY-ESO-1/ISCOMATRIX and 54 to ISCOMATRIX alone. No significant toxicities were observed. There were no differences between the study arms in relapses at 18 months or for median time to relapse; 139 vs 176 days (p=0.296), or relapse rate, 27 (48.2%) vs 26 (48.1%) (HR 0.913; 95% CI 0.402 to 2.231), respectively. RFS and OS were similar between the study arms. Vaccine recipients developed strong positive antibody responses to NY-ESO-1 (p≤0.0001) and NY-ESO-1-specific CD4 + and CD8 + responses. Biopsies following relapse did not demonstrate differences in NY-ESO-1 expression between the study populations although an exploratory study demonstrated reduced (NY-ESO-1) + /Human Leukocyte Antigen (HLA) class I + double-positive cells in biopsies from vaccine recipients performed on relapse in 19 participants., Conclusions: The vaccine was well tolerated, however, despite inducing antigen-specific immunity, it did not affect survival endpoints. Immune escape through the downregulation of NY-ESO-1 and/or HLA class I molecules on tumor may have contributed to relapse., Competing Interests: Competing interests: IDD, WC and JSC are coinventors on International Patent Application No: PCT/US2004/032147 ('In vivo efficacy of NY-ESO-1 plus adjuvant'). JFT has received honoraria for advisory board participation from Merck Sharpe Dohme Australia and Bristol-Myers Squibb Australia. He has also received honoraria and travel expenses from GSK and Provectus Inc. GAM has received research funding from Pfizer, Celgene and Ventana; acted as a consultant/advisor for Provectus; and received travel funding from Roche and Novartis. EW serves as consultant/advisor for Eli Lilly and Merck Serono, and has received travel funding from Roche. PN has received non-financial support from Novartis, as well as personal fees from Novartis and GlaxoSmithKline for advisory board participation. MPNF serves as consultant for, and has received travel funding from Sirtex. PGC has received payment for attending BMS advisory boards. RV declares stock or other ownership at Agenus, Dynavax and Soligenix. EM is an employee of, and holds stock in CSL Limited. ID is supported by an NHMRC Practitioner Fellowship (APP1102604). PRD is a founder and shareholder in SapVax which provides research funding to his laboratory., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Free-electron lasers (FELs) based on superconducting accelerator technology and storage ring facilities operate with bunch repetition rates in the MHz range, and the need arises for bunch-by-bunch electron and photon diagnostics. For photon-pulse-resolved measurements of spectral distributions, fast one-dimensional profile monitors are required. The linear array detector KALYPSO (KArlsruhe Linear arraY detector for MHz-rePetition rate SpectrOscopy) has been developed for electron bunch or photon pulse synchronous read-out with frame rates of up to 2.7 MHz. At the FLASH facility at DESY, a current version of KALYPSO with 256 pixels has been installed at a grating spectrometer as online diagnostics to monitor the pulse-resolved spectra of the high-repetition-rate FEL pulses. Application-specific front-end electronics based on MicroTCA standard have been developed for data acquisition and processing. Continuous data read-out with low latency in the microsecond range enables the integration into fast feedback applications. In this paper, pulse-resolved FEL spectra recorded at 1.0 MHz repetition rate for various operation conditions at FLASH are presented, and the first application of an adaptive feedback for accelerator control based on photon beam diagnostics is demonstrated., (open access.)

Although lipid excipients are of increasing interest for development of taste-masked and modified release formulations, the drug release instability and the lack of mechanistic understanding in that regard still prevent their larger-scale application. In this work, we investigated the physical stability of a binary (tripalmitin/polysorbate 65) lipid coating formulation with a known stable polymorphism. The coating composition was characterized using DSC to construct the phase diagram of binary system and polarized light microscopy to display the microstructure organization. The water uptake and the erosion of slabs cast from the coating formulations were investigated post-production and after storage. Subsequently, N-acetylcysteine particles were coated with the selected formulations and the drug release stability was investigated. Additionally, microstructure characterization was performed via SEM and X-ray diffraction. The drug release instability was explained by polysorbate 65 and tripalmitin phase growth during storage, especially at 40°C, suggesting that polysorbate 65 can leak out of tripalmitin spherulitic structures, creating lipophilic and impermeable tripalmitin regions. The growth of polysorbate 65 phase leads to larger hydrophilic channels with reduced tortuosity. This work indicates that for obtaining stable drug release profiles from advanced lipid formulations, microphase separation should be prevented during storage., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The aim of the present work was to develop a PAT strategy for the supervision of hot melt coating processes. Optical fibers were placed at various positions in the process chamber of a fluid bed device. Experiments were performed to determine the most suitable position for in-line process monitoring, taking into account such requirements as a good signal to noise ratio, the mitigation of dead zones, the ability to monitor the product over the entire process, and reproducibility. The experimental evidence suggested that the position at medium fluid bed height, looking towards the center, i.e., normal to particle movement, proved to be the most reliable position. In this study, the advantages of multipoint monitoring are shown, and an in-line-implementation was created. This enabled the real-time supervision of the process, including the fast detection of inhomogeneities and disturbances in the process chamber, and the compensation of sensor malfunction. In addition, a model for estimating the particle size distribution via NIR was successfully created. This ensures that the quality of the product and the endpoint of the coating process can be determined correctly.

Multiparticulate dosage forms are a recent strategy to meet the special needs of children, elderly people and patients suffering from dysphagia. Our study presents a novel and cost-efficient approach for the manufacturing of a taste-masked multiparticulate system with a stable immediate release profile by applying lipid-based excipients in a solvent-free hot melt coating process. The thermosensitive N-acetylcysteine (N-ac) was used as model drug and hot-melt coated with a mixture of tripalmitin and polysorbate 65. A predictive in vitro method for the evaluation of the taste masking efficiency was developed based on the deprotonation of the carboxyl group of N-ac and the decline of pH, responsible for the unpleasant sour taste of the compound. The method was confirmed using in vivo studies. Differential scanning calorimetry and X-ray scattering experiments revealed polymorphic transformation and its dependency on transformation time, temperature and emulsifier concentration. During the process, the coating was transformed almost completely into the stable β-polymorph, leading to an unaltered dissolution profile during storage. A statistical design was conducted that revealed the critical process parameters affecting the taste masking efficiency and drug release. This study shows the successful application of solvent-free hot-melt coating in the development of a taste-masked and stable formulation., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Hot-melt coating is of growing interest, because it does not require solvents, resulting in reduced process times and costs. However, excipients for this technology are mainly triacylglycerides (TAGs) or their derivatives, which exhibit polymorphism, surface disruption, and complex crystallite networks, affecting the release profile of produced microcapsules. In this work, anhydrous citric acid crystals were coated with molten tristearin using conventional inlet air temperatures (microcapsules A) and temperatures above the melting point of α-form (microcapsules B). Additionally, microcapsules A were tempered to achieve polymorphic stability (microcapsules AB). The product yield and coating efficacy were above 90% and 97%, respectively, demonstrating the feasibility and efficacy of the process. Small angle X-ray scattering analysis confirmed that the tristearin shell of microcapsules B is in the β-form with a larger average crystallite size than microcapsules A and AB. Scanning electron microscopy images revealed a nonbloomed surface of microcapsules B. We showed that blooming does not play a critical role in the drug release, but the apparent diffusion coefficient of drug is dramatically reduced by increasing TAGs crystallite size and resulting tortuosity. This work brings new insights on the micrometric properties of solid lipid dosage forms, being an important step to prevent the overuse of excipients with unknown toxicity., (© 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.)

Chronic stress may lead to neuronal atrophy and functional impairments within the CNS, and increasing evidence indicates that exercise can protect the brain from these changes. Bax is a key protein of the B-cell lymphoma (Bcl) family that complexes within the mitochondrial membrane and forms pores to initiate cellular apoptosis. Herein, we measured cortical Bax levels following chronic and acute stress via immunoblotting. We reveal that chronic, but not acute, stress increases cortical levels of Bax oligomer 270, a complex revealed in previous studies to be associated with apoptosis. Several recent studies have revealed that physical exercise can protect rodents from neurochemical and/or behavioral changes occurring with stress. Previous studies have also revealed that voluntary exercise enhances the expression and activation of cellular proteins associated with enhanced neuronal survival. Herein, we reveal that 3 weeks of daily restraint led to increased oligomerization of Bax within the cerebral cortex, and that chronic corticosterone administration had a similar effect. Voluntary wheel running, concurrent with chronic restraint, prevented an increase in Bax oligomer 270. Analysis of subcellular fractions also revealed that the combination of exercise with chronic stress reduced the percent of total Bax localized to the mitochondria. Ours is the first study to investigate dynamic molecule complexes associated with the initiation of apoptosis with stress, and the influence of exercise upon the levels of these complexes, suggesting that exercise is an effective preventative measure that can promote neuronal survival and protect the brain against the damaging effects of chronic stress.

Background: While an association between androgens and different types of aggression has been well documented in male offenders, the influence of androgens on externalizing behavior in adolescents at risk for antisocial behavior has not been investigated so far., Methods: Plasma levels of the main androgen metabolites testosterone (T) and 5alpha-dihydrotestosterone (DHT) were measured in N = 87 fourteen-year-old (36 boys, 51 girls) from a prospective longitudinal study of children at risk. Externalizing behavior at age 8, 11 and 14 was assessed using the Achenbach Child Behavior Checklist (CBCL) and Teacher Report Form (TRF)., Results: Significant higher androgen levels (T, DHT) were found in male, but not in female adolescents with elevated scores of externalizing behavior. Moreover, boys with persistent externalizing behavior exhibited the highest levels of plasma androgens., Conclusions: There is a link between T, DHT and externalizing behavior in male adolescents at risk for psychopathology. Due to the findings of highest androgen levels in boys with persistent externalizing behavior, a role of androgens in the development of disruptive or later antisocial disorders can be hypothesized.

Background: The major aldosterone metabolite 3 alpha,5 beta tetrahydroaldosterone reflects up to 45% of the aldosterone secretion. Its 24-h urinary excretion is likely to provide an accurate index of the daily aldosterone production and to be an indicator for primary aldosteronism (PA)., Methods: In a prospective study, the validity of tetrahydroaldosterone as a screening test for PA was evaluated in comparison to serum potassium, plasma aldosterone, plasma renin activity, plasma aldosterone/renin activity ratio (PARR), as well as 24-h urinary aldosterone-18-glucuronide and free aldosterone. A total of 111 normotensive individuals, 412 PA patients and 1453 essential hypertensive patients, were studied. The effect of blood sampling technique on potassium level was also investigated., Results: Tetrahydroaldosterone differentiated PA from essential hypertension with a sensitivity of 96% and a specificity of 95%. The sensitivity was 89% for plasma aldosterone, 87% for free aldosterone, 85% for PARR, 71% for aldosterone-18-glucuronide and 51% for renin activity. Specificities varied between 91% and 85%. The combined use of the parameters plasma aldosterone > or =9.0 ng/dL and PARR > or =25 resulted in a sensitivity of 82% and specificity of 95%. Forearm exercise proved to be a source of erroneous elevations of potassium sufficient to obscure the suspicion of PA., Conclusion: The data suggest that tetrahydroaldosterone is the most reliable screening test for PA. Tetrahydroaldosterone determination in combination with aldosterone-18-glucuronide and free aldosterone increases diagnostic specificity for PA. Potassium, renin, plasma aldosterone, and basal PARR are inadequate screening procedures because they are subject to high rates of false-positive and false-negative results.

Objective: While an association between androgens and different types of aggression has been well documented in male offenders, the influence of androgens on externalizing behavior in adolescents at risk for antisocial behavior has not been investigated so far., Methods: Plasma levels of the main androgen metabolites testosterone (T) and 5a-dihydrotestosterone (DHT) were measured in N = 119 14-year-olds (51 boys, 68 girls) from a prospective longitudinal study of children at risk. The Achenbach Child Behavior Checklist (CBCL) and the Youth Self Report Form (YSR) were used to assess externalizing behavior at age 14., Results: The CBCL revealed significant positive correlations between DHT levels and the subscales "externalizing problems" and the problem scales "aggressive behavior" and "delinquent behavior" in male adolescents. Only the YSR subscale "delinquent behavior" exhibited a marginally significant association with DHT. Neither scale showed any significant correlations between androgen levels and externalizing behavior in female adolescents., Conclusions: Earlier findings of androgen effects on aggressive and antisocial behavior in male offenders were confirmed for male adolescents from a general population sample. The results stress the importance of the androgen metabolite DHT.

Unlabelled: The two-phase restorative proctocolectomy is the treatment of choice for surgical therapy of the familial adenomatous polyposis (FAP) and also for the ulcerative colitis (UC). Besides the well-known complications the entire removal of the colorectum leads to an impairment of fluid and electrolyte resorption., Patients and Methods: Over a time period of two years we observed 320 proctocolectomized patients with ileal pouch-anal anastomosis (IPAA). All patients with high pouch output but without organic malfunction were identified. The organic reasons were excluded with the help of pouchoscopy, radiography or MR imaging. We evaluated routine parameters, the kidney function, the electrolyte changes, the acid-base balance and the urine pH, as well as the hormonal changes of the suprarenal glands. We identified seven patients with 'high pouch output' out of 320 patients observed. The control group consisted of 14 proctocolectomized patients without hints of complications in the endoscopic, radiographic and routine laboratory diagnostics., Results: Neither group showed any significant differences in the analysis of the routine parameters. A significant drop of the urine sodium concentration of 40.5 +/- 18.7 mmol/l (control group 98 +/- 43.4 mmol/l) was observed in the group with 'high pouch output'. In this group the plasma aldosterone values were strongly increased with an average of 42.6 +/- 28.9 ng/dl (control group 13.2 +/- 6.8 ng/dl) as well as the plasma 18-hydroxycorticosterone with an average of 153.7 +/- 121.1 ng/dl (control group 153.7 +/- 121.1 ng/dl). Neither group of patients showed increased activity of free corticosterone and free cortisol. Only free 11-desoxycorticosterone was elevated in the group with 'high pouch output'., Conclusion: Our results prove that the mineralocorticoid adrenal activity plays a central role in order to preserve the volume and electrolyte homeostasis. The low frequency of 'high-pouch-output'-complications in realms of the restorative proctocolectomy proves the excellent compensation of the removal of the colon mucosa. Plasma aldosterone seems to be a diagnostic marker encapsulating the reabsorption problems of intestinal salt and volume losses after proctocolectomy.

Background: The Ileo-Pouch-Anal-Anastomosis (IPAA) is the standard restorative procedure for Ulcerative Colitis and Familial Adenomatous Polyposis (FAP). IPAA may lead to considerable losses of fluids, especially in association with a protective loop ileostomy., Aim: The aim of this study was to investigate adrenal mechanisms in the regulation of volume homeostasis immediately after IPAA and protective ileostomy., Methods: For that purpose, 20 patients out of our patient population with elective IPAA with ileostomy participated in this study between 1993 and 1997. In all patients, routine laboratory tests and gluco- and minealocorticoid hormone measurements were performed preoperatively and 10 days after operation., Results: These blood analyses indicated functional hyperaldosteronism immediately after IPAA. Significantly elevated levels of Aldosterone (36.4 +/- 25.1 ng/dl) and 18-OH-Corticosterone ( 173 +/- 11.3 ng/dl) were found. Among hormones with glucocorticoid effects, blood levels of Cortisol (10.4 +/- 4.8 microg/dl) were significantly elevated, while 11-Desoxycortiosterone (13.9 +/- 8.4 ng/dl) and Corticosterone (0.8 +/- 0.6 microg/dl) were not significantly elevated. Serum electrolytes remained unchanged., Conclusions: Our results indicate that hormones with mineralocorticoid effects play a predominant role in the compensation of ileostomy losses after IPAA.

Adrenal insufficiency is suspected in some ill preterm infants. The aim of this prospective study was to compare serum cortisol concentrations during the first 2 wk of life of well preterm infants (group A) less than 30 wk of gestational age with the cortisol concentrations of ill preterm infants whose arterial hypotension-a potential sign of adrenal insufficiency-had been treated with catecholamine (group B), and the cortisol concentrations of ill preterm infants who had not been so treated (group C). Cortisol concentrations did not differ significantly between group A (240 nmol/l, 58-659; n = 46) (median, minimum-maximum) and group C (268 nmol/l, 58-1007; n = 25). Group B had a double-peaked distribution of cortisol. Two subgroups were formed by taking the highest cortisol level of group A as a threshold: group B1 (110 nmol/l, 41-378; n = 20) and group B2 (1200nmol/l, 764-1482; n = 8). The cortisol concentrations of group B1 were significantly lower (p = 0.00097) compared to the cortisol concentrations of the well preterm infants (group A). The severity of illness, which was quantified by two scoring systems, differed significantly among the groups (p < 0.003 for all comparisons) with the following sequence: A < C < B, but not between B1 and B2, as clinical variables were not different between the subgroups.

Aim: To establish a reference range for serum cortisol concentrations in preterm infants with a gestational age of less than 30 weeks during the first two weeks of life., Methods: Infants were prospectively classified by the following exclusion criteria: surfactant administration, arterial hypotension, acute or uncontrolled infection, ventricular haemorrhage II degrees or above, serum glucose < 2.2 mmol/l, exchange transfusion, stress as a result of any kind of examination or nursing for at least 4 hours before blood sampling. The cortisol value was measured once using radioimmunoassay in each infant., Results: In appropriate for gestational age (AGA) infants (n = 37, median gestational age 27.7 weeks, median birthweight 1030 g) the distribution of the cortisol concentrations was non-Gaussian. These had a nearly normal distribution, when log(10) values of the data were used. The points determined by mean (2 SD) on the logarithmic scale were transformed back to the original units to provide a reference range: 73-562 nmol/l. Gestational age was significantly (p = 0.033) associated with cortisol values (log(10)) with a regression coefficient (standard error) of -0.045 (0.020). Small for gestational age (SGA) infants (n = 8) had significantly higher cortisol values (median 357 nmol/l) than AGA infants (median 199 nmol/l) (p=0.028)., Conclusions: There is a strictly defined reference range of serum cortisol concentrations in AGA preterm infants.

Purpose: Restorative proctocolectomy is a standard procedure in the surgical treatment of ulcerative colitis and familial adenomatous polyposis. The radical removal of the colorectum with construction of an ileostomy often results in high stoma losses. These may lead to changes in the electrolyte and acid-base balance and to alterations in renal and suprarenal gland function., Methods: In this study 33 patients who received an ileoanal pouch before and after proctocolectomy were investigated at different time intervals for electrolyte changes, alteration of the acid-base balance, kidney function, and hormonal changes of the suprarenal glands. Measurements were performed before proctocolectomy, ten days after proctocolectomy with ileal pouch-anal anastomosis under protective loop ileostomy, before ileostomy closure, and 6 to 12 months after ileostomy closure. Neither acute renal failure nor other vital complications were observed., Results: Statistical analysis showed a significant decrease of urine pH to 5.4 +/- 0.22 (before ileostomy closure) and metabolic acidosis (pH 7.32 +/- 0.04; base excess -1.3 +/- 5.6 (before ileostomy closure)). Likewise, we found a decrease in renal clearance to 86 ml/minute (before ileostomy closure) without signs of tubular damage. The most important change during the phase with ileostomy was a functional secondary hyperaldosteronism with aldosterone levels of 63.2 +/- 70.8 ng/dl (before ileostomy closure). In comparison with preoperative levels, there was a ten-fold increase in mineralocorticoid adrenal activity. Additionally, during the period with protective ileostomy, the hepatic synthesis of aldosterone-18-glucuronide was only slightly increased, and the cortisol/cortisone ratio was extremely decreased., Conclusions: These results show that restorative proctocolectomy with ileal pouch-anal anastomosis and protective loop ileostomy significantly influences fluid, electrolyte, and acid-base balance. Functional secondary hyperaldosteronism is of central importance for subsequent renal recompensation. Approximately one-half year after ileostomy closure, the endogenous hormones with mineralocorticoid effects returned to normal levels.

The variable response of patients with idiopathic nephrotic syndrome (NS) to glucocorticoid (GC) treatment has not been explained. Earlier studies indicated that the response is limited by cellular GC receptors. We investigated these receptors in mononuclear leukocytes of 28 pediatric patients with NS divided into three groups: steroid-sensitive in relapse, steroid-sensitive in remission, and steroid-resistant. Density and binding affinity of GC receptors were determined by a dexamethasone binding assay; no significant differences were found between the three patient groups and between these and healthy controls, although a few patient values fell outside the range of controls. Total and free plasma concentrations of cortisol were low in all three patient groups. A weak positive correlation was found between the number of GC receptors and total plasma cortisol (r=0.36, P=0.03). The results suggest that factors other than GC receptors that mediate the cellular effects of GC are involved in the variable response of NS patients to GC.

There is a large body of evidence that points to a systemic link between the somatotropic axis and sex hormones, but epidemiologic data on the interactions between the two hormonal systems are still missing. We examined here the associations between the plasma levels of insulin-like growth factor (IGF) I, IGF-II, IGF-binding protein 3 (IGFBP-3), and sex hormones in a population-based sample of 486 men and women, aged 50-80 yr. The strongest association was an age-independent inverse correlation between all three circulating IGF components and sex hormone-binding globulin (SHBG), the major testosterone-binding protein in plasma. Consistent with this, bio-available (non-SHBG-bound) but not total testosterone levels were positively associated with the IGF system in men, and 3 alpha-androstanediol glucuronide was positively correlated with circulating IGFs in women. Moreover, part of the correlation between the circulating IGF system and bone mineral density at the femur and the calcaneus could be accounted for by SHBG. Our data suggest that sex hormones and the GH/IGF system are significantly interrelated in the elderly population. These hormonal interactions may play an important role in human aging and the pathogenesis of age-related diseases.

In order to assess hypothalamic-pituitary-adrenocortical axis function, we conducted low and single oral dose metyrapone tests (35 mg/kg) in dexamethasone treated very low birth weight infants with bronchopulmonary dysplasia (n = 12). The responses to metyrapone of tetrahydro-11-deoxycortisol (THS) and cortisol metabolites were analyzed by gas chromatography and mass spectrometry in 24-h urinary specimens. For comparative reasons, morning plasma 11-deoxy-cortisol and cortisol were measured by radioimmunoassay before and after metyrapone. No side effects of metyrapone were observed in our patients. In 5 of 12 patients, no urinary THS could be stimulated after metyrapone and most of the other patients had small increases in urinary THS. These findings suggest suppressed or strongly impaired hypothalamic-pituitary-adrenocortical axis function in most patients. While the concentrations of plasma 11-deoxycortisol showed little variation, those of plasma cortisol were grossly different from the respective urinary values. We recommend steroid analysis in 24-h urinary specimens by gas chromatography and mass spectrometry, because urinary steroids provide more information and the highly specific analytical technique is independent of phenomena such as cross reactivity or matrix effects. The low and single oral dose metyrapone test in combination with urinary steroid analysis by gas chromatography and mass spectrometry therefore provides a noninvasive, convenient and safe means of evaluating the integrity of the hypothalamic-pituitary-adrenocortical axis in very low birth weight infants.

Ten cases of adrenal adenomas, one case with unilateral adrenal hyperplasia, and another case with apparent bilateral are reported, in whom an alternative pathway of aldosterone via 21-deoxyaldosterone is operative. They all manifested hypertension, low renin activity, low normal potassium values, as well as high urinary excretion rates of 21-deoxyaldosterone and its related metabolite Kelly's-M1 steroid. In all cases, urinary aldosterone metabolites (aldosterone-18-glucuronide and tetrahydroaldosterone) and aldosterone precursor 18-hydroxycorticosterone levels were normal. Hence, the adrenal lesions give rise to hyper-21-deoxyaldosteronism. 21-Deoxyaldosterone is a weak mineralocorticoid, and its elevated production in the presence of normal aldosterone can induce a pathological state of hypermineralocorticoidism. Adrenalectomy resulted in normalization of hypertension in six of eight and amelioration in two of eight cases. Six of seven adenoma cases examined as well as the case of unilateral adrenal hyperplasia were sensitive to ACTH. One of the seven adenomas and, as expected, the case with apparent bilateral hyperplasia were angiotensin responsive. Histologically and electron microscopically, the operated adenomas consisted predominantly of clear cells, characterized by mitochondria with tubulo-vesicular internal structure similar to those of the zona fasciculata (in contrast, our classical Conn's adenoma with normal 21-deoxyaldosterone excretion exhibited a more heterogenous histological appearance and were, in terms of ultrastructure, more similar to cells of the zona glomerulosa). Ultrastructurally and immunocytochemically, the clear cells of 21-deoxyaldosterone adenomas showed features of both the zona glomerulosa and the zona fasciculata and are, hence, considered to be hybrid cells. We conclude that the determination of 21-deoxyaldosterone and Kelly's-M1 should be considered in the diagnosis of mineralocorticoid-induced forms of hypertension, especially when an adrenal adenoma has been detected with an imaging procedure.

In the present study the aldosterone-18-glucuronide and tetrahydroaldosterone values in 24 hour urine collections of healthy nonpregnant women, women with normal pregnancies and women with pregnancy induced hypertension (PIH) were compared. In pregnancy an elevated excretion of both aldosterone metabolites was found. The Q-ratio (aldosterone-18-glucuronide/tetrahydro-aldosterone+aldosterone-18-glu cur onide) was also increased compared to healthy nonpregnant women. The elevated Q-ratios point out to increased formation of aldosterone-18-glucuronide. This predominantly renal metabolite may reflect greater availability of aldosterone molecules for interaction with mineralocorticoid receptor in the kidney.

21-Deoxyaldosterone has been postulated to be a precursor of aldosterone in an alternative biosynthesis pathway and Kelly's-M1 is considered to be its metabolite. In healthy volunteers, the excretion rate of 21-deoxyaldosterone and of Kelly's-M1 are significantly lower than the aldosterone metabolites, aldosterone-18-glucuronide and tetrahydro-aldosterone and than the aldosterone precursor 18-OH-corticosterone. Essential hypertension patients (with low and normal renin) excrete comparable values of 21-deoxyaldosterone and Kelly's-M1 as normotensives. In 66% of aldosterone-producing adenoma cases (APA) and in 60% of idiopathic hyperaldosteronism (IHA) patients, significantly raised values of 21-deoxyaldosterone and Kelly's-M1 were found. The patients with the high excretion rates of both steroids showed only moderately increased values of the aldosterone metabolites, aldosterone-18-glucuronide and tetrahydro-aldosterone, as well as of the aldosterone precursor 18-OH-corticosterone. In contrast, the latter mentioned steroids were excreted in higher amounts in those patients with normal excretion of 21-deoxyaldosterone and Kelly's-M1. Hence, it is suggested that aldosterone is produced alternatively either via 18-OH-corticosterone alone or additionally via 21-deoxyaldosterone. Furthermore, in three cases of "incidentally" discovered adrenal adenomas, 21-deoxyaldosterone and Kelly's-M1 were the only elevated steroids. After adrenalectomy, excretion of 21-deoxyaldosterone and of Kelly's-M1 and blood pressure returned to normal, which proves that these steroids play a role in blood pressure regulation. In essential hypertension, ACTH infusion induced a significant increase of 21-deoxyaldosterone and Kelly's-M1. However, the increase after angiotensin II was 3- to 6-fold higher than after ACTH. IHA patients proved to be more responsive to angiotensin II; and, in contrast, APA cases proved to be more sensitive to ACTH. The data suggest that beside the main route of aldosterone biosynthesis via 11-deoxycorticosterone, corticosterone and 18-OH-corticosterone an alternative pathway exists via 21-deoxyaldosterone in healthy and in hypertensive patients. There are similarities between the regulation of 21-deoxyaldosterone and the regulation of aldosterone. The determination of 21-deoxyaldosterone and its possible metabolite Kelly's-M1 might be appropriate in the diagnosis of mineralocorticoid-induced forms of hypertension, especially when an adrenal adenoma is discovered.

A 21-year-old woman with weight loss, palpitations and facial flush was found to have hypertension (up to 200/130 mm Hg) and mild hyperkalaemia (3.4 mmol/l). Extensive diagnostic tests revealed hyperaldosteronism with contrast storing in the right adrenal gland on scintigraphy after injection of dexamethasone (2 mg daily for one week). The hyperaldosteronism could not be suppressed by dexamethasone. Analysis of venous blood separately from each side pointed to aldosterone production in the right adrenal (right renal vein: 80 ng/dl, drainage area of the right adrenal vein: 114 ng/dl, left renal vein: too low to measure). The right adrenal gland was removed. No adenoma was found histologically. After the operation the aldosterone level was reduced and the blood pressure transiently fell. But both had risen again after 3 months. Renewed tests revealed dexamethasone-remediable hyperaldosteronism. On treatment with hydrocortisone (15-5-5 mg) and 50 mg metoprolol the patient became normotensive without any other medication.

We report on three cases of Corticosterone Methyl Oxidase Typ II deficiency in two siblings and one boy. All three children were presented with typical symptoms of a saltlosing syndrome (vomiting, poor drinking, weight loss, hypotonia). Hyponatremia and hyperkalemia, low plasma aldosterone concentrations when related to high plasma-renin-activities suggested deficiency in the final steps of aldosterone biosynthesis. Variable degrees of enzyme deficiency and no relation of biochemical findings to the clinical symptoms were observed. Clinical symptoms became less severe with age. Diagnosis of CMO II-deficiency was established by an abnormal high ratio of 18-hydroxycorticosterone to aldosterone, by measurement of their precursors and metabolites in plasma and urine. In one sibling negative values may have been caused by suppression of the renin-angiotensin-system due to high sodium replacement therapy.

Pregnancy-induced hypertension (PIH) is a frequent cause of maternal and neonatal morbidity and mortality. In the present study we focused on the pathophysiology of PIH, mainly on the role of mineralocorticoids, reversed blood pressure patterns, and the resulting necessity of continuous monitoring of the preeclamptic mother. Problems of antihypertensive therapy are discussed and the first results of a pilot study with Urapidil are presented. To examine the role of mineralocorticoids in the pathophysiology of PIH, we studied plasma aldosterone and 18-hydroxy-corticosterone (18-OH-B) levels in 25 women with PIH and in 25 healthy pregnant women. Furthermore, we evaluated the mineralocorticoid receptor (MR) count in mononuclear leukocytes in the 2 groups. The MR-count was significantly decreased in the PIH-group. The values of plasma aldosterone and 18-OH-B were also low. These results cannot be explained by receptor down-regulation due to higher level of mineralocorticoids of the zona glomerulosa. Perhaps deoxycorticosterone or a hitherto unknown mineralocorticoid is responsible for the hypertension and altered MR-status. The first results of continuous blood pressure measurements with a noninvasive, real-time blood pressure monitor (Finapres) are presented. The comparison of the obtained values with intraarterial measurements demonstrates a good correlation between the two methods. We also report on the first experiences with Urapidil in the treatment of hypertension in severe preeclampsia. The data show that hypertension in preeclamptic women can be treated by Urapidil without side effects or reflex-tachycardia. Further studies will have to prove if Urapidil is suited for prepartal treatment of PIH as well.

A midpubertal girl presented with secondary amenorrhea and a rapidly progressive deepening of her voice as the only signs of virilization. Diagnostic work-up yielded an extremely elevated plasma testosterone (289 ng/dl), low estradiol (29 pg/ml) levels and a large solitary cyst of the right ovary, which was totally removed. Pathohistology was in keeping with a granulosa cyst with mild luteinization. Normalization of testosterone (to 27.3 ng/dl) and estradiol (to 62 pg/ml) and resumption of regular menses after 2 months clearly indicated an autonomous function of the cyst. A malignant tumor was unequivocally excluded. Basal and ACTH stimulated levels of adrenal androgens pointed to a late-onset 3 beta-hydroxysteroid dehydrogenase deficiency, which per se is known to induce polycystic ovarian changes, but to date has never been described to be accompanied with a large and autonomous follicular cyst.

Thirteen morbidly obese individuals were studied prospectively for 1 year after vertical banded gastroplasty (VBG) to determine the relationships between energy balance equation parameters and excess weight loss. The measured energy expenditure (MEE), as determined by indirect calorimetry, was not correlated with weight loss. However, when this parameter was expressed as a ratio to the predicted energy expenditure (PEE), the ratio was significantly correlated with the postoperative excess weight loss at 2, 6, and 12 months. The mean daily energy intake after the VBG was 2715 +/- 865 kJ. The postoperative energy intake was not correlated with the excess weight loss. Diet-induced thermogenesis was studied in eight patients. The mean diet-induced thermogenesis was 10.31% +/- 13.92%. The diet-induced thermogenesis was not correlated with the postoperative excess weight loss. The preliminary findings of this trial suggest that the MEE/PEE ratio is useful in predicting excess weight loss after VBG.

We studied glucocorticoid receptor autoregulation and corticotropin response to dexamethasone in depressed patients and controls, attempting to control for the confounding effect of endogenous glucocorticoids. After depletion of endogenous cortisol, depressed patients showed an attenuated suppressibility of corticotropin by dexamethasone in the face of unchanged dexamethasone plasma levels. Beta-endorphin levels were strongly correlated with adrenocorticotropic hormone (ACTH) concentrations. Although metyrapone administration resulted in a marked rise of glucocorticoid receptor sites per cell in controls, this effect was not present in depressives. These data support the hypothesis of a decreased glucocorticoid receptor plasticity and a partial steroid resistance in depression.

Although minor disturbances of the circadian serum cortisol rhythm and diminished excretion of steroid metabolites have been reported in patients with atopic dermatitis, test assays regarding subtle neuroendocrine alterations have not been employed so far. We therefore studied the serum concentrations of cortisol, prolactin and adrenocorticotropin under baseline conditions, after 1 mg dexamethasone and after a defined methylprednisolone treatment in 15 patients with atopic dermatitis, in comparison with 10 healthy controls. The assessment of the hormones revealed no remarkable differences between either group at any of the blood sampling time points. However, in 3 patients and 2 control subjects, though exhibiting no concomitant disease, we could find no suppression of endogenous cortisol to below 5 micrograms/dl after oral intake of 1 mg dexamethasone. These cortisol non-suppressors showed lower dexamethasone serum concentrations in the morning after its administration, as compared with the suppressors. Acute (1 mg dexamethasone) or prolonged (40 mg methylprednisolone over 6 days) intake of glucocorticoids suppressed prolactin levels in both groups, demonstrating that the effect of glucocorticoids on the hormone system is not restricted to the hypothalamic-pituitary-adrenal axis. Our results indicate an intact feedback response of this hormonal axis to 1 mg dexamethasone and the ability of long-term as well as acute glucocorticoid administration to influence the prolactin secretion in patients with atopic dermatitis.

Although treatment comprising a combination of methylprednisolone (MP) and troleandomycin (TAO) has been employed to treat cases of severe bronchial asthma requiring high doses of corticosteroids, for about 20 years, now, it has always been associated with major adverse reactions (1). A new protocol avoids these adverse effects by a rapid reduction in the dose of MP to alternating administrations and low TAO dosage (250 mg). Nineteen patients were treated using this protocol, 16 of whom for more than two months (maximum 21, minimum 4 months). Three patients were taken out of the study as early non-responders in the initial phase. Five patients must be considered to be late non-responders, or were discharged from the study on account of pathological liver parameters. In 8 patients who showed good tolerance, an appreciable reduction in the dose of steroids, with stabilisation of the asthma, was observed.

This randomized double-blind placebo-controlled study was undertaken in a series of 179 patients to determine whether phenytoin administered soon after head injury lessens the incidence of late posttraumatic epilepsy. When delayed hypersensitivity to phenytoin developed, the patient was switched to phenobarbital. The patients were followed for 18 months to detect the occurrence of seizures and to serially measure plasma phenytoin concentrations. There was no significant difference in the percentage of patients having late seizures in the treated and placebo groups (p = 0.75). The time between injury and seizures did not significantly differ between the two groups. The results provide no support for the continued use of phenytoin in the low therapeutic range for prophylaxis against late posttraumatic seizures. It cannot be concluded that higher phenytoin plasma concentrations and higher compliance rates than obtained in this study would not have significantly decreased the occurrence of late posttraumatic epilepsy. The finding that no patient with a phenytoin plasma concentration of 12 microgram/ml or higher had a seizure raises the question of whether phenytoin in blood concentrations in higher therapeutic ranges might lessen the occurrence of posttraumatic epilepsy, and should be studied further. Posttraumatic epilepsy is a major public health problem deserving a large cooperative trial to determine if phenytoin at higher blood levels than obtained in this study, or other currently available or newly developed drugs, can prevent the occurrence of posttraumatic epilepsy.

Rats with unilateral nephrectomy were offered 1% sodium chloride as drinking fluid and were injected with desoxycorticosterone trimethylacetate (D.O.C.-T.M.A.) at weekly intervals. During the fourth to seventh week after the start of the experiment, malignant hypertension developed in most of the animals: body weight fell, reflecting volume depletion; serum osmolality and serum sodium and urea concentrations increased; in the kidneys malignant nephrosclerosis occurred. In such animals, plasma concentrations of arginine-vasopressin were increased ten-fold in comparison with control animals; intravenous injection of a specific vasopressin antibody resulted in a transient fall of blood-pressure (B.P.) to normal or subnormal levels, while the injection of an angiotensin-I or angiotensin-II antibody did not affect B.P. In control animals none of the antibodies had an effect on B.P. It is concluded that in the pathogenesis of malignant D.O.C. hypertension vasopressin plays a role similar to that of renin-angiotensin in malignant renal hypertension.

Metabolites of aldosterone were extracted from human urine collected over three days following the intravenous injection of a tracer dose of tritium labelled hormone. After enzymic hydrolysis, steroids were separated by column, paper and thin-layer chromatography and the polarities of the labelled metabolites were compared with the chromatographic properties of known aldosterone products. The pattern of metabolites changed over the three days, from that associated with typical aldosterone metabolites, to less polar metabolites. Materials in the organic extract from a pH-1 hydrolysate of pooled pregnancy urine, were located by their ability to bind with aldosterone and tetrahydroaldosterone antisera and exhibited similar chromatographic properties to the radioactive metabolites. Using GC-MS, the identity of this immunoactive material could not be established in extracts after purification from 200 ml pregnancy urine but some synthetic derivatives of aldosterone as candidate compounds, were excluded.

Plasma concentrations of betamethasone, cortisol and corticosterone were measured before and after intraarticular injection of a betamethasone-depot preparation (Celestan-Depot) by radioimmuno-assay in 31 patients. Plasma concentration of betamethasone reached its maximum of between of 10 and 17 microgram/dl 30 min after injection. It had fallen to half after 2 hours, and practically to nil from the eighth day onwards. Lowest plasma levels of cortisol and corticosterone occurred after 6--24 hours, returning to the normal range after four days. In nine patients with knee-joint effusion and synovitis the plasma concentration of betamethasone was significantly higher after 24 hours, and cortisol and corticosterone values after 48 hours significantly more suppressed, than in patients without joint effusions and signs of inflammation. The results indicate that plasma concentration of betamethasone and the suppressant effect on the adrenal cortex after intra-articular injection is similar to that after intramuscular applications. Correspondingly, systemic application of the cortisol derivatives can cause significant side effects and be contra-indicated also after intra-articular injection.

In a prospective clinical study, an electronic intravenous (IV) rate controller was compared with a standard roller clamp for control of IV infusions. The electronic IV rate controller was associated with fewer complications and more accurate fluid therapy than was the roller clamp. There was also a substantial savings of nursing time and a potential for cost savings when the electronic IV rate controller was used.

Plasma hydrocortisone (cortisol) levels in 7 healthy volunteers were measured following administration of 0.25 mg betamethasone or 0.25 mg betamethasone and 1 mg dimetindene maleate. The H1-receptor antagonist dimetindene maleate did not influence the hydrocortisone suppressing activity of betamethasone, which was proved by comparison with the published plasma hydrocortisone levels of 162 young healthy untreated volunteers.

Calorie and protein supplementation improves nutritional status. This support may improve outcome and decrease morbidity and mortality in acutely brain-injured patients. Investigators have observed a poor tolerance to enteral feedings after brain injury and have noted that this persists for approximately 14 days postinjury. This delay has been attributed to increased gastric residuals, prolonged paralytic ileus, abdominal distention, aspiration pneumonitis, and diarrhea. In the present investigation, 23 brain-injured patients with an admission 24-hour peak Glasgow Coma Scale (GCS) score between 4 and 10 were studied for 18 days from hospital admission. The mean duration from injury to initiation of full-strength, full-rate enteral feeding was 11.5 days. Seven of the 23 patients tolerated enteral feedings within the first 7 days following hospital admission (mean 4.3 days), four patients tolerated feedings between 7 and 10 days postadmission (mean 9 days), and 12 patients did not tolerate feedings until after 10 days postinjury (mean 15.9 days). There was a marginally significant relationship between low GCS scores on admission and length of days to enteral feeding tolerance (p = 0.07). A significant inverse relationship was observed between daily peak intracranial pressure (ICP) and time to tolerance of feedings (p = 0.02). There was no significant relationship between feeding tolerance and days to return of bowel sounds (p = 0.12). Serum albumin levels decreased during the investigation (mean +/- standard error to the mean: 3.2 +/- 0.12 gm/dl on Day 1; 2.7 +/- 0.23 gm/dl on Day 16; normal = 3.5 to 5.0 gm/dl), whereas the percentage of patients tolerating feedings increased over the course of the study. The authors conclude that patients with acute severe brain injury do not adequately tolerate feedings via the enteral route in the early postinjury period. Tolerance of enteral feeding is inversely related to increased ICP and severity of brain injury. It is suggested that parenteral nutritional support is required following brain injury until enteral nutrition can be tolerated.

A randomized double-blind placebo-controlled study was carried out to determine whether phenytoin administered soon after injury lessens the incidence of epilepsy in the 1st week after severe head trauma. In this study, 244 patients were randomized into either a phenytoin or placebo group. The patients in the phenytoin group were administered phenytoin intravenously or intramuscularly within 24 hours of hospital admission. Patients in the placebo group received intravenous or intramuscular diluent. The patients were switched from parenterally administered phenytoin or placebo as soon as oral doses could be tolerated. Over 78% of the phenytoin patients had plasma concentrations of at least 10 micrograms/ml at 1, 3, and 7 days after injury. There was no significant difference in the percentage of patients having early seizures in the treated and placebo groups (p = 0.99). There was no significant difference in the interval from injury to first seizure between the treated and placebo groups (p = 0.41). The early administration of phenytoin did not lessen the occurrence of seizures in the 1st week after head injury. Since the effectiveness of seizure prophylaxis has not been established, the authors suggest that anticonvulsant drugs be administered only after an early seizure has occurred.

In 66 cases of carcinoma of the breast the estradiol receptors was determined and in 16 cases the progesterone receptor additionally, too. This was done in order th decide about endocrine therapy. The results of estrogen and progesterone receptors estimations were compared and correlated both the type of carcinoma and the degree of its histologic differentiation.

The rate of hydrolysis of different water soluble esters of corticoids was determined with newly developed specific radioimmunoassays in healthy subjects. It can be found, that triamcinoloneacetonide phosphate was significantly faster transformed into free form after i.v. application than the reference substances prednisolone- and methylprednisolone hemisuccinate. Moreover the plasma concentration of free triamcinolone-acetonide decreases much faster than that of free prednisolone and methylprednisolone. This shows, that triamcinoloneacetonide is distributed wider and very quickly, probably in the intracellular fluid volume. At this time it is not clear, whether only free steroids are biologically active or the water soluble derivatives as well. Our results can be of clinical importance because of the different rates of hydrolysis as well as of differences in the diffusion.

The effects of subcutaneous injections of synthetic ACTH during 14 subsequent days has been studied in the rat. ACTH caused a loss in body weight which was related to a negative water balance. Blood pressure rose rapidly and reached values higher than 180 mm Hg in all rats after 10 days of ACTH administration. During this period, urinary excretion of corticosterone and 18-hydroxy-deoxycorticosterone (18-OH-DOC) was increased more than ten times, while aldosterone excretion was increased only during the first two days. After withdrawal of ACTH, excretion of steroids normalized, or in some cases was even suppressed and water balance and body weight gain returned to normal values. However, blood pressure remained slightly higher than in controls after ten days. The effects of ACTH on water balance and blood pressure resemble those of corticosterone in the rat. The rapidly induced and sustained changes in blood pressure by ACTH administration suggest that this may be an useful model of experimental hypertension.

After a dexamethasone suppression test (DST), cortisol, corticosterone, and the test substance were determined by a direct radioimmunoassay in 42 samples obtained from 22 depressed patients and 8 controls. The DST results of both glucocorticoids agreed in most of the tests. In all seven cases with elevated but not definitely abnormal post-DST (1600 hr) cortisol levels (transitional range 30-50 ng/ml) the concurrent determination of corticosterone indicated that this corticosteroid may serve as a potent additional discriminator. Dexamethasone plasma concentrations at 1600 hr after a 1-mg test dose of dexamethasone at 2300 hr were significantly (p less than 0.01) lower in cortisol and corticosterone nonsuppressors than in suppressors. Since these data were obtained 17 hr after ingestion of dexamethasone (half-life 3.5-5 hr) any conclusions about an inverse correlation between dexamethasone and corticosteroid plasma concentrations would be speculative. However, the dexamethasone pharmacokinetics might be an important variable and may contribute to some of the recent uncertainty about the DST.

The results of a second operation for tumor removal in 24 adult patients with supratentorial glioblastoma multiforme or anaplastic astrocytoma were analyzed. The median survival time after reoperation was 14 weeks. Five of the 24 patients lived 6 months or longer after reoperation. Only three of these patients maintained a Karnofsky rating (KR) of at least 60 for 6 months or longer after reoperation. Preoperative neurological status (KR) is the most significant determinant of survival after reoperation (p = 0.02). When the KR is at least 60, median survival after reoperation is 22 weeks. When the KR prior to reoperation is less than 60, median survival is 9 weeks. Only one of 13 patients with a KR of less than 60 prior to reoperation survived longer than 6 months after the second operation. The interval between first and second operation is significantly related to survival (p = 0.03), but when adjustment is made for the KR the interoperative interval is no longer significantly related to survival after the second operation (p = 0.39). Age, sex, and location of tumor were not significantly related to duration of survival. This study suggests that reoperation is most likely to produce the best result when the KR is at least 60 and the interval between operations is longer than 6 months. Using these criteria, one-third of the patients could be expected to survive with a KR of at least 60 for 6 months. The study indicates that reoperation should not be carried out when the KR is less than 60.

Male Sprague-Dawley rats with unilateral renal artery stenosis and a contralateral untouched kidney develop a malignant hypertension (MH) which is characterized by high blood pressures, sodium and water depletion, and subsequent activation of the renin-angiotensin system. In the present studies we found plasma arginine vasopressin (AVP) concentrations-3-fold higher than those in rats with benign renal hypertension, and 4- to 5-fold higher than those in normotensive control rats. Analysis of individual values showed considerable scatter; about 50% of the values fell in the range of benign hypertensive or control rats. When a specific AVP antiserum was injected, iv, into eight conscious unrestrained MH rats, BP transiently fell toward control values in four; in one, BP fell by only 10 mm Hg, and three other MH rats showed no response. In the same rats, injection of a specific angiotensin II antiserum always induced a transient fall in BP. On the basis of these and previously reported observations, we conclude that, subsequent to sodium and water loss and activation of the renin-angiotensin system, vasopressin release is stimulated in a significant number of MH rats and that, in these rats, vasopressin may cause significant systemic vasoconstriction. Thereby vasopressin may contribute to the development of malignant renal hypertension in rats.

The pharmacokinetics of fluocortolone (Ultralan oral) and its effect on plasma cortisol levels were investigated during long-term treatment of patients with rheumatic and haematological diseases with different doses of fluocortolone. Fluocortolone was administered in the morning and plasma levels of fluocortolone and cortisol were measured in samples obtained 1.5, 3, 4, and 5 h p. adm. by means of specific radioimmunoassays. Maximum concentrations of fluocortolone in plasma (Cmax) and areas under the fluocortolone plasma level curves (AUC) increased linearly with the dose. The peak time (tmax = 2.04 +/- 0.85 h) and the plasma half-life (t1/2 = 1.53 +/- 0.52 h) were independent of the dose administered. Cortisol suppression as indicated by morning cortisol levels below 50 ng/ml plasma was not observed with doses below 10 mg/d.

1. The determination of aldosterone-18-glucuronide (pH 1-labile aldosterone) was complemented by concomitant measurements of free urinary aldosterone and tetrahydroaldosterone in 307 patients, most of whom were hypertensive. In 38 cases (12.3%) the normal, aldosterone-18-glucuronide concentration was clinically misleading, but increased free aldosterone and/or tetrahydroaldosterone values suggested the presence of hyperaldosteronism, which in many of these cases was confirmed by elevated excretion of the possible major aldosterone precursor 18-hydroxycorticosterone (18-OH-B). 2. Of 224 patients with essential hypertension and normal or low plasma renin activity 18 had an elevated free aldosterone and/or tetrahydroaldosterone excretion without increased aldosterone-18-glucuronide. These cases may represent early or pre-symptomatic forms of primary hyperaldosteronism. In other cases, particularly when tetrahydroaldosterone was increased alone, abnormalities of aldosterone metabolism were suspected. 3. In two out of 15 patients with primary hyperaldosteronism, aldosterone-18-glucuronide values were frequently found to be normal, although elevations were noted in other variables. However, no relation to the morphological abnormality (adenoma versus hyperplasia) was seen.