Search

Aims To compare pharmacokinetic characteristics of two biphasic insulin aspart (BIAsp) formulations: BIAsp30 and BIAsp70 (30% and 70%, respectively, of fast-acting insulin aspart) during 15 days of multiple dosing (thrice daily).Methods A total of 22 patients with Type 1 diabetes (nine women, 13 men) aged 41.4 +/- 9.9 years (mean +/- SD) with a diabetes duration of 18.9 (2.3 40.3) years (median and range) completed the randomized, double-blinded, two-period crossover study. On day 1 and day 15 of each treatment period, 24-h serum insulin and glucose profiles were evaluated. Total area under the insulin aspart concentration time curve (AUC(0-24 h)), AUC after dinner administration stratified into early (AUC(dinner(0-6 h)) and intermediate-phase (AUC(dinner(6-14 h)), maximum insulin concentration (Cmax), time to maximum insulin concentration (Tmax) after each meal were recorded.Results On day 15 BIAsp70 was associated with a shorter Tmax, and more than 40% elevated Cmax. Comparing with BIAsp30, AUC(0-24 h) and AUC(dinner(0-6 h) were increased by 25% and 28%, respectively, but AUCdinner (6-14 h) was markedly lower for BIAsp70 [BIAsp30/BIAsp70: 1.9; 95% CI (1.42, 2.55)]. Similar findings were also observed on day 1. The fasting or pre-meal serum insulin levels on day 15 tended to be higher with BIAsp30, but the differences were not statistically significant.Conclusions The pharmacokinetic properties of BIAsp30 and 70 remain constant during 2 weeks of daily administration in patients with Type 1 diabetes. In comparison with BIAsp30, the administration of BIAsp70 results in a shorter time to and larger maximum insulin aspart concentration. Furthermore, total and early post-dinner insulin AUC were greater, whereas late-phase insulin exposure was lower with BIAsp70. [ABSTRACT FROM AUTHOR]

Competing Interests: No potential conflicts of interest relevant to this article were reported.

Fosamprenavir is a phosphate ester prodrug that, upon dissolution, is cleaved to the poorly soluble yet readily absorbable parent drug amprenavir. In this study, a novel cell-free in vitro setup with quasi-continuous monitoring of the dynamic dissolution/bio-conversion/permeation of fosamprenavir was designed and tested. It consists of side-by-side diffusion cells, where the donor and acceptor compartments are separated by the biomimetic barrier PermeaPad®, and sampling from the donor compartment is accomplished via a microdialysis probe. Externally added bovine alkaline phosphatase induced bioconversion in the donor compartment. Microdialysis sampling allowed to follow the enzymatic conversion of fosamprenavir to amprenavir by the bovine alkaline phosphatase in an (almost) real-time manner eliminating the need to remove or inactivate the enzyme. Biomimetic conversion rates in the setup were established by adding appropriate amounts of the alkaline phosphatase. A substantial (6.5-fold) and persistent supersaturation of amprenavir was observed due to bioconversion at lower (500 µM) concentrations, resulting in a substantially increased flux across the biomimetic barrier, nicely reflecting the situation in vivo. At conditions with an almost 10-fold higher dose than the usual human dose, some replicates showed premature precipitation and collapse of supersaturation, while others did not. In conclusion, the proposed novel tool appears very promising in gaining an in-depth mechanistic understanding of the bioconversion/permeation interplay, including transient supersaturation of phosphate-ester prodrugs like fosamprenavir., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: The prevalence of obstructive coronary artery disease (CAD) in symptomatic patients referred for diagnostic testing has declined, warranting optimization of individualized diagnostic strategies., Objectives: This study sought to present a simple, clinically applicable tool enabling estimation of the likelihood of obstructive CAD by combining a pre-test probability (PTP) model (Diamond-Forrester approach using sex, age, and symptoms) with clinical risk factors and coronary artery calcium score (CACS)., Methods: The new tool was developed in a cohort of symptomatic patients (n = 41,177) referred for diagnostic testing. The risk factor-weighted clinical likelihood (RF-CL) was calculated through PTP and risk factors, while the CACS-weighted clinical likelihood (CACS-CL) added CACS. The 2 calculation models were validated in European and North American cohorts (n = 15,411) and compared with a recently updated PTP table., Results: The RF-CL and CACS-CL models predicted the prevalence of obstructive CAD more accurately in the validation cohorts than the PTP model, and markedly increased the area under the receiver-operating characteristic curves of obstructive CAD: for the PTP model, 72 (95% confidence intervals [CI]: 71 to 74); for the RF-CL model, 75 (95% CI: 74 to 76); and for the CACS-CL model, 85 (95% CI: 84 to 86). In total, 38% of the patients in the RF-CL group and 54% in the CACS-CL group were categorized as having a low clinical likelihood of CAD, as compared with 11% with the PTP model., Conclusions: A simple risk factor and CACS-CL tool enables improved prediction and discrimination of patients with suspected obstructive CAD. The tool empowers reclassification of patients to low likelihood of CAD, who need no further testing., Competing Interests: Author Relationship With Industry This work was supported by the Steno Partner Collaboration Unit, Gødstrup Hospital, Herning, Denmark. Drs. Winther, Schmidt, and Bøttcher have received institutional research grant support from Acarix. Dr. Schmidt is a part-time consultant for Acarix. Dr. Schmidt is a minor shareholder of Acarix. Dr. Hoffmann has received institutional research grants on behalf of Massachusetts General Hospital, outside of the submitted work, from KOWA, MedImmune, AstraZeneca, and HeartFlow; and has received consultant fees from DCRI and Recor, outside of the scope of the submitted work. Dr. Wijns has received research grants and honoraria from MicroPort. Dr. Christiansen has served on the Advisory Board for Novo Nordisk. Dr. Saraste has received speaker fees from AstraZeneca, Amgen, Bayer, Novartis, and Abbott; and has served on the Advisory Board for AstraZeneca and Amgen, outside of the submitted work. Dr. Bøttcher has served on the Advisory Board for Novo Nordisk, AstraZeneca, Bayer, Sanofi, and Acarix, outside of submitted work. Dr. Knuuti has received speaker fees from GE Healthcare, Merck, Lundbeck, and Bayer; and has received study protocol consultant fees from GE Healthcare and AstraZeneca, outside of the submitted work. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2020 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: 11 C-Donepezil positron emission tomography (PET) allows non-invasive assessment of cholinergic innervation of visceral organs. We aimed to compare cholinergic innervation in the gut in patients with diabetes mellitus (DM) and in healthy controls (HC)., Methods: 11 C-Donepezil PET and computed tomography (CT) were performed in 19 patients with type 1 DM and gastrointestinal symptoms and in 19 age- and sex-matched HC in a cross-sectional design., Key Results: All patients had severe gastrointestinal symptoms when assessed by standard questionnaires. DM patients had significantly increased volume of the small intestinal wall (DM: median 557 cm 3 [interquartile range [IQR] 446-697] vs HC median: 448 cm 3 [IQR; 341-518; P < .01]), and the 11 C Donepezil PET uptake was reduced in patients (DM: median 7.08 standardized uptake value [SUV] [IQR; 5.94-8.43] vs HC: median 9.18 SUV [IQR; 8.57-10.11; P < .01]). A similar pattern was found in colon (DM: median volume 1064 cm 3 [IQR; 882-1312] vs HC: median 939 cm 3 [IQR; 785-1081; P = .13] and DM: median 1.22 SUV (IQR; 1.08-1.36) vs HC: median 1.42 SUV (IQR; 1.32-1.53; P = .03). Furthermore, patients had significantly reduced pancreatic volume (DM: median 53 cm 3 [IQR; 41-69] vs HC: median 98 cm 3 [IQR;82-110; P < .01]) and reduced PET uptake of the pancreas (DM: median 13.14 SUV [IQR;9.58-15.82] vs HC: median 21.46 SUV [IQR;18.97-24.06; P < .01]) as well as the adrenal gland (DM: median 7.62 SUV [IQR;7.61;15.82] vs HC: median 15.51 SUV [IQR;12.22;19.49; P = .03])., Conclusion and Inferences: Assessed with 11 C-Donepezil PET/CT, patients with DM and severe bowel symptoms have reduced cholinergic innervation of the gut indicative of parasympathetic denervation., (© 2019 John Wiley & Sons Ltd.)

CDX2 is routinely used for identifying gastrointestinal origin of metastatic adenocarcinomas; but a high percentage of other carcinomas also show positivity with this antibody. SATB2 is a new immunohistochemical marker with a few studies showing that it is specifically expressed in a large majority of colorectal adenocarcinomas. We assessed SATB2 along with CDX2 in patient material with metastasis in order to determine whether the primary site could be identified as 'colon-rectum'. Metastasis in 67 liver biopsies, 108 lymph nodes from resection specimens and 36 serous effusions was analyzed retrospectively. Blinded slides stained for CDX2 and SATB2 were assessed individually by two pathologists and sensitivity, specificity and kappa statistics were calculated. Sensitivity for CDX2 in metastasis from colorectal adenocarcinomas was 93%; while in SATB2 it was 79%. The combination of CDX2 and SATB2 yielded a sensitivity of 79% and a high specificity of 93%. There was an acceptable level of agreement (κ = 0.64) between the pathologists for both the markers in case of colorectal adenocarcinoma metastasis. CDX2 is a sensitive marker compared to SATB2; while the specificity of combination of CDX2 and SATB2 is high for metastasis from colorectal adenocarcinoma. SATB2 can be used as a supplementary marker along with CDX2 to identify colorectal origin for material received from patients clinically presenting with metastasis., (© 2018 APMIS. Published by John Wiley & Sons Ltd.)

This is the report of a case of a 63-year-old woman, with a history of recurrent deep vein thrombosis, who was admitted with abdominal pain and diagnosed with bilateral adrenal hemorrhage, resulting in acute adrenal insufficiency. Several risk factors for adrenal hemorrhage were present: stress because of infection, treatment with the factor Xa-inhibitor rivaroxaban and the presence of antiphospholipid antibodies. Venous thrombosis of the adrenal glands with subsequent hemorrhagic infarction is a possible mechanism. It is currently unclear if patients with antiphospholipid syndrome can be treated effectively and safely with a nonvitamin K-antagonist oral anticoagulant.

Glucagon-like peptide (GLP)-1 analogues such as liraglutide have gained popularity in the treatment of type 2 diabetes over the last years. By mimicking the effects of the native GLP-1, it enhances the glucose-dependent secretion of insulin, suppresses elevated glucagon secretion, increases satiety and slows down gastric emptying. Because of its ways of action it is not likely to cause hypoglycaemia in cases of overdosage. We present a 45-fold overdose of liraglutide (confirmed by P-liraglutide measurements) leading to nausea and vomiting, but no hypoglycaemia and no sign of pancreatitis.

We present a case of amoebic colitis, misdiagnosed as inflammatory bowel disease and treated with corticosteroids, leading to severe necrotizing enterocolitis. We review the literature on the epidemiology, pathogenesis, diagnosis, and treatment of amoebic dysentery, with special emphasis on the association between immunosuppressive treatment and the development of severe invasive amoebiasis.

Context: Adrenal derived androgens are low in women with adrenal failure. The physiological consequences of substitution therapy are uncertain., Objective: To investigate the effects of DHEA substitution in women with adrenal failure on body composition, fuel metabolism, and inflammatory markers. DESIGN, PARTICIPANTS AND INTERVENTION: In this study, ten female patients (median age 38.5 years, range 28-52) with adrenal failure were treated with DHEA 50 mg for 6 months in a double-blind, randomized, placebo-controlled, and crossover study. The participants underwent dual-energy X-ray absorptiometry (DXA) scan, computed tomography scan of abdominal fat, indirect calorimetry, bicycle ergometry, muscle and fat biopsies, and blood samples., Results: Baseline androgens were normalized to fertile range during active treatment. Anthropometric data were unaffected, but lean body mass (LBM) slightly increased compared with placebo (delta LBM (kg) placebo versus DHEA: -0.48±6.1 vs 1.6±3.4, P=0.02) with no alterations in total or abdominal fat mass. PTH increased with DHEA, but no significant changes were observed in other bone markers or in bone mineral content. The mRNA levels of markers of tissue inflammation (adiponectin, interleukin 6 (IL6), IL10, monocyte chemoattractant protein 1, and tumor necrosis factor α) in fat and muscle tissue were unaffected by DHEA treatment, as was indirect calorimetry and maximal oxygen uptake. A high proportion of self-reported seborrheic side effects were recorded (60%)., Conclusion: In female adrenal failure, normalization of androgens with DHEA 50 mg for 6 months had no effects on muscle, fat, and bone tissue and on fuel metabolism in this small study. A small increase in LBM was observed. Treatment was associated with a high frequency of side effects.

A 69-year-old woman was admitted with diarrhoea, anaemia and elevated C-reactive protein. She was diagnosed with metastases of a carcinoma to the colon; the immunohistochemical profile made lobular breast cancer the most likely primary tumour. But despite thorough examination, such tumour was never found. Twenty-two years earlier, the patient underwent surgery for a benign breast tumour. The benign diagnosis was confirmed in new slides from the then removed tissue. Metastases from breast cancer to the colon are rare, and a primary tumour is usually found. In this case report, however, no primary tumour was found.

Objective: Hypopituitarism, often characterized by hypogonadism, is associated with central obesity, increased cardiovascular and endocrine morbidity and mortality. In Turner syndrome, which is also characterized by hypogonadism liver enzymes are often elevated, but readily suppressed by a short course of hormone replacement therapy (HRT). We investigated the effect of HRT on liver enzymes, lipid levels and measures of insulin sensitivity 26 in hypopituitary women., Design: We studied 26 hypopituitary women (age 38.8+/-11.0 (mean+/-SD years), BMI 27.4+/-5.1kg/m(2)) during HRT and 28days off therapy., Methods: We measured liver enzymes, fasting levels of lipids, insulin and glucose as well as adiponectin and leptin levels. Body composition was assessed by means of anthropometry and bioimpedance., Results: Alanine transaminase (ALT) and aspartate transaminase (AST) increased after discontinuation of HRT (ALT; treated: 22.3+/-11.5 vs. untreated: 27.1+/-11.1 (U/L) (P<0.02); AST; treated: 20.4+/-6.1 vs. untreated: 24.6+/-8.9 (U/L) (P<0.002)), whereas other liver function tests remained unchanged. Measures of insulin sensitivity and fasting lipids were also unaffected by HRT, whereas leptin levels decreased with cessation of HRT (leptin; treated: 23 (8-71) vs. untreated: 20 (8-64) (mug/L) (P<0.0005))., Conclusion: Short time discontinuation of HRT in young hypopituitary women increased liver enzymes, whereas measures of insulin sensitivity and lipid levels remained unchanged. We speculate that the estrogen component of HRT has beneficial effects on hepatic metabolism through various pathways. Further studies including liver imaging and with a time-dependent design are needed to clarify the role of HRT on liver enzyme levels, metabolic variables and liver fat content., (Copyright 2009 Elsevier Ltd. All rights reserved.)

Prostate-specific membrane antigen (PSMA) is a transmembrane protein highly expressed in advanced and metastatic prostate cancers. The pathologic consequence of elevated PSMA expression in not known. Here, we report that PSMA is localized to a membrane compartment in the vicinity of mitotic spindle poles and associates with the anaphase-promoting complex (APC). PSMA-expressing cells prematurely degrade cyclin B and exit mitosis due to increased APC activity and incomplete inactivation of APC by the spindle assembly checkpoint. Further, expression of PSMA in a karyotypically stable cell line induces aneuploidy. Thus, these findings provide the first evidence that PSMA has a causal role in the induction of aneuploidy and might play an etiologic role in the progression of prostate cancer.

Context: Cortisol is an important catabolic hormone, but little is known about the metabolic effects of acute cortisol deficiency., Objective: The objective of the study was to test whether clinical symptoms of weight loss, fatigue, and hypoglycemia could be explained by altered energy expenditure, protein metabolism, and insulin sensitivity during cortisol withdrawal in adrenocortical failure., Design, Participants, and Intervention: We studied seven women after 24-h cortisol withdrawal and during replacement control during a 3-h basal period and a 3-h glucose clamp., Results: Cortisol withdrawal generated cortisol levels close to zero, a 10% decrease in basal energy expenditure, increased TSH and T(3) levels, and increased glucose oxidation. Whole-body glucose and phenylalanine turnover were unaltered, but forearm phenylalanine turnover was increased. During the clamp glucose, infusion rates rose by 70%, glucose oxidation rates increased, and endogenous glucose production decreased. Urinary urea excretion decreased by 40% over the 6-h study period., Conclusions: Cortisol withdrawal increased insulin sensitivity in terms of increased glucose oxidation and decreased endogenous glucose production; this may induce hypoglycemia in adrenocortical failure. Energy expenditure and urea loss decreased, indicating that weight and muscle loss in Addison's disease is caused by other mechanisms, such as decreased appetite. Increased muscle protein breakdown may amplify the loss of muscle protein.

Prostate specific membrane antigen (PSMA) is a transmembrane glycoprotein expressed almost exclusively in prostatic epithelial cells. Expression of PSMA is elevated in prostate cancer, with levels closely correlated with disease grade. Although the highest levels of PSMA expression are associated with high-grade, hormone-refractory and metastatic prostate cancer, the significance of elevated PSMA expression in advanced prostate cancer has yet to be fully elucidated. We provide evidence that prostatic carcinoma cells expressing PSMA exhibit reduced motility and increased attachment when grown on a bone marrow matrix substrate. This phenomenon occurs via activation of focal adhesion kinase and provides the first evidence of a link between PSMA expression and prostate cancer metastasis to the bone.

Microtubules (MTs) are linked to cell mechanobiology. "Stable" and "dynamically unstable" microtubule (MT) subtypes are differentially sensitive to growth and distribution in serum starved (SS) versus full serum (FS) conditions. Atomic Force and Immunofluorescence microscopies were used to study the nanomechanical properties of the cell membrane in response to serum conditions and nocodazole. Nanomechanical properties of the cell membrane remain unchanged under SS/FS conditions even though there are drastic MT changes. The cell membrane is shown to depend on unstable MTs and the intermediate filament (IF) networks to maintain local stiffness. Measurements of local membrane nanomechanics in response to nocodazole display characteristic serum dependent decays. The responses suggest that the cell exists in a mechanical transition state. Stiffness is shown to depend on the interplay between dynamically unstable MTs, stable MTs and IFs which all act to impart a distinct cellular type of transient "metastability".

Background: Female adrenal insufficiency implicates reduced production of the adrenal androgen precursor dehydroepiandrosterone (DHEA) and low androgen levels. Oral DHEA restores androgen deficit but the clinical implications and safety of substitution therapy is uncertain. A putative DHEA receptor in vascular endothelium has been described and in vitro studies have shown involvement of DHEA in NO dependent pathways., Aim: To evaluate effects of DHEA substitution on cardiovascular parameters., Design: Six months randomized, double-blind, placebo-controlled crossover study. Treatment consisted of DHEA 50-mg or placebo. Each treatment period was followed by a 2-month washout period., Material and Methods: Ten females with documented adrenal failure were included. Androgen levels were measured. Cardiovascular evaluation was performed before and after every treatment period. Two patients left the study because of skin side effects and anxiety, respectively. All patients had low circulating androgens baseline and normal range androgens during DHEA treatment. We examined patients with noninvasive endothelial cell function, magnetic resonance imaging (MRI)-based cardiac output, echocardiography, ambulatory 24-h blood pressure and maximal oxygen consumption., Results: DHEA treatment normalized androgen status to levels seen in healthy women. DHEA and placebo treatment had no effect on echocardiographic parameters of myocardial dimensions or systolic and diastolic function, noninvasive endothelial cell function at the level of the brachial artery, 24-h blood pressure and heart rate, cardiac output and maximal oxygen consumption during exercise cycle testing. Remarkably, all participants had evidence of concentric left ventricular remodelling by echocardiography., Conclusion: Restoration of physiological androgen levels using 6 months of DHEA replacement in this pilot study did not affect cardiovascular parameters and endothelial function in female adrenal insufficiency.

Prostate-specific membrane antigen (PSMA) is a protein up-regulated in the vast majority of prostate cancers. Antibodies to PSMA have proved highly specific for prostate cancer cells, and the therapeutic potential of such antibodies is currently being assessed in clinical trials. We have previously shown that PSMA at the cell surface of polarized epithelial cells is predominantly expressed at the apical plasma membrane and that microtubule depolymerization abolishes apical PSMA targeting. In the current report, we implicate a functional role for a target membrane soluble N-ethylmaleimide-sensitive factor adaptor protein receptor, syntaxin 3, in the microtubule-dependent apical targeting of PSMA. PSMA and syntaxin 3 are similarly localized to the apical plasma membrane of the prostatic epithelium and Madin-Darby canine kidney cells. Introduction of a point mutation into syntaxin 3 abolishes its polarized distribution and causes PSMA to be targeted in a nonpolarized fashion. Additionally, treatment of polarized Madin-Darby canine kidney cells with vinblastine, a microtubule depolymerizing chemotherapeutic agent, causes both syntaxin 3 and PSMA to redistribute in a nonpolarized fashion. However, following treatment with the microtubule stabilizing chemotherapeutic agent Taxotere, both syntaxin 3 and PSMA continue to localize in a polarized manner at the apical plasma membrane. Thus, microtubule depolymerizing and stabilizing chemotherapeutic drugs might exact similar cytotoxic effects but have disparate effects on protein targeting. This phenomenon might have important clinical implication, especially related to antibody-mediated immunotherapy, and could potentially be exploited for therapeutic benefit.

For most carcinomas, progression toward malignancy is accompanied by loss of epithelial differentiation and a shift towards a mesenchymal phenotype. This process, referred to as epithelial to mesenchymal transition (EMT), exacerbates motility and invasiveness of many cell types and is often considered a prerequisite for tumor infiltration and metastasis. However, there are numerous examples of advanced carcinomas that adopt some mesenchymal features, yet retain characteristics of well-differentiated epithelial cells. We provide a review of these reports and describe mechanisms to explain the morphologic and molecular heterogeneity and plasticity of malignant carcinoma cells, including incomplete EMT, reversion to an epithelial phenotype, and collective migration. We suggest that these mechanisms can manifest in a series of independent and reversible steps and that EMT represents just one mechanism in the global metastatic carcinoma development process.

Prostate-specific membrane antigen (PSMA) is a transmembrane protein with a highly restricted profile of expression. Expression is primarily limited to secretory cells of the prostatic epithelium, with elevated levels observed in prostate cancer. As an integral membrane protein correlated with prostate cancer, PSMA offers a potentially valuable target for immunotherapy. PSMA is also detected in the neovasculature of a variety of solid tumors but not in the endothelial cells of preexisting blood vessels. Although the significance of PSMA expression in these cells remains elusive, this pattern of expression implies that PSMA may perform a functional role in angiogenesis and may offer a therapeutic target for the treatment of a broad spectrum of solid tumors. In this study, we have expressed PSMA in human microvascular endothelial cells and demonstrate that PSMA binds to caveolin-1 and undergoes internalization via a caveolae-dependent mechanism. The association between PSMA and caveolae in endothelial cells may provide important insight into PSMA function and ways to best exploit this protein for therapeutic benefit.

Objective and Design: Compared with their male counterparts, healthy females secrete more growth hormone (GH) and those with GH-deficiency have lower insulin-like growth factor I (IGF-I) levels and are less responsive to GH substitution. To test whether this gender difference is related to sex hormones we measured androgen status and IGF-I related parameters in 38 hypopituitary women (mean (range) age 41.5 (20-58) years) during continued GH substitution as compared with a control group of 38 healthy women matched for age and menopausal status. Twenty six patients were studied twice: with estrogen replacement and after 28 days of estrogen discontinuation in a randomised design., Results: The patients were androgen deficient compared with controls (median, range), dehydroepiandrosterone sulphate (DHEAS): 185 (99-7800) nmol/l vs 4400 (820-13,000) nmol/l, P=or<0.001; androstenedione: 0.5 (0.1-7.1) nmol/l vs 4.3 (1.6-8.8) nmol/l, P=or<0.001; dihydrotestosterone (DHT): 0.13 (0.09-0.54) nmol/l vs 0.55 (0.09-0.89) nmol/l, P=or<0.001; testosterone: 0.28 (0.09-1.56) nmol/l vs 1.1 (0.71-2.24) nmol/l, (P=or<0.001); free testosterone: 0.004 (0.001-0.030) nmol/l vs 0.016 (0.001-0.030) nmol/l, P=or<0.001. The circulating levels of IGF-I, IGF-II, IGF-binding protein 1 (IGFBP-1), and IGFBP-3 did not differ between patients and controls. The subgroup of patients receiving hydrocortisone (HC) replacement (n=24) had significantly lower levels of androgens (suppressed by 80-100%) as well as IGF-I and IGFBP-3 as compared with the patients not receiving HC. IGF-I was correlated to free testosterone in patients (r=0.57, P=0.0005) as well as controls (r=0.43, P=0.008), and free testosterone was a significant positive predictor of IGF-I. Estrogen discontinuation induced an increase in IGF-I (167+/-15 vs 206+/-14 microg/l, P=0.005 and IGFBP-3 (3887+/-139 vs 4309+/-138 microg/l, P=0.0005). Estrogen discontinuation was associated with a significant increase in median (range) free testosterone (0.004 (0-0.02) vs 0.0065 (0-0.03) nmol/l, P=0.001) and a significant decrease in median (range) sex-hormone binding globulin (SHBG; 93 (11-278) vs 55.5 (20-142) nmol/l, P=0.001). DeltaIGF-I correlated with DeltaSHBG (r=-0.45 P=0.033) and DeltaIGFBP-3 (r=0.67 P=or<0.001). In a regression model DeltaE2, Deltatestosterone, DeltaSHBG and DeltaIGFBP-3 explained 93% of the variation in DeltaIGF-I., Conclusions: Androgen levels are low in hypopituitary women and free testosterone correlates with IGF-I. Discontinuation of estrogen replacement in these patients induces elevations in IGF-I as well as free testosterone, and DeltaIGF-I correlated positively with Deltafree testosterone. These effects may contribute to the gender differences observed in the GH-IGF axis in healthy adults as well as in the responsiveness of hypopituitary patients to GH substitution.

Prostate-specific membrane antigen (PSMA) is an important biomarker expressed in prostate cancer cells with levels proportional to tumor grade. The membrane association and correlation with disease stage portend a promising role for PSMA as an antigenic target for antibody-based therapies. Successful application of such modalities necessitates a detailed knowledge of the subcellular localization and trafficking of target antigen. In this study, we show that PSMA is expressed predominantly in the apical plasma membrane in epithelial cells of the prostate gland and in well-differentiated Madin-Darby canine kidney cells. We show that PSMA is targeted directly to the apical surface and that sorting into appropriate post-Golgi vesicles is dependent upon N-glycosylation of the protein. Integrity of the microtubule cytoskeleton is also essential for delivery and retention of PSMA at the apical plasma membrane domain, as destabilization of microtubules with nocodazole or commonly used chemotherapeutic Vinca alkaloids resulted in the basolateral expression of PSMA and increased the uptake of anti-PSMA antibody from the basolateral domain. These results may have important relevance to PSMA-based immunotherapy and imaging strategies, as prostate cancer cells can maintain a well-differentiated morphology even after metastasis to distal sites. In contrast to antigens on the basolateral surface, apical antigens are separated from the circulation by tight junctions that restrict transport of molecules across the epithelium. Thus, antigens expressed on the apical plasma membrane are not exposed to intravenously administered agents. The ability to reverse the polarity of PSMA from apical to basolateral could have significant implications for the use of PSMA as a therapeutic target.

Prostate-specific membrane antigen (PSMA) is a metallopeptidase expressed predominantly in prostate cancer (PCa) cells. PSMA is considered a biomarker for PCa and is under intense investigation for use as an imaging and therapeutic target. Although the clinical utility of PSMA in the detection and treatment of PCa is evident and is being pursued, very little is known about its basic biological function in PCa cells. The purpose of this review is to highlight the possibility that PSMA might be a multifunctional protein. We suggest that PSMA may function as a receptor internalizing a putative ligand, an enzyme playing a role in nutrient uptake, and a peptidase involved in signal transduction in prostate epithelial cells. Insights into the possible functions of PSMA should improve the diagnostic and therapeutic values of this clinically important molecule.

Objective: In female adrenal insufficiency, dehydroepiandrosterone (DHEA) secretion is impaired and circulating androgen levels are severely reduced. We wanted to analyse the acute effects of physiological DHEA substitution on substrate metabolism., Design: We studied nine females with adrenal insufficiency after 9 days of oral DHEA replacement (50 mg/day) in a double-blind, placebo-controlled crossover study., Methods: Whole body and regional substrate metabolism was assayed in the basal state and during a euglycemic hyperinsulinemic glucose clamp by means of isotope dilution techniques (glucose, phenylalanine, tyrosine), indirect calorimetry and in situ lipolysis (microdialysis technique)., Results: DHEA treatment normalized the levels of all androgens. Basal and insulin-stimulated total energy expenditure and rates of protein, lipid and glucose oxidation were unaffected by DHEA. Whole body turnover of glucose and protein were also unaffected by DHEA. Forearm breakdown of protein was reduced by insulin to the same extent after placebo and DHEA. Insulin sensitivity as expressed by the glucose infusion rate during the euglycemic clamp was similar after placebo and DHEA. Finally, the interstitial release of glycerol in adipose tissue was not significantly influenced by DHEA., Conclusions: Short-term oral DHEA replacement in women with adrenal insufficiency was not associated with measurable changes in total or regional substrate metabolism.

Objective: In women, GH secretion is strongly influenced by oestrogen status, whereas the role of androgens is unclear. We, therefore, examined GH secretory dynamics during low vs. normalized androgen levels in women with adrenal failure., Patients: Ten females with adrenal failure (AF), mean age of 42 years (range 22-54 years)., Design: The effects of 8 days of oral dehydroepiandrosterone (DHEA; 50 mg/day) were studied in a double-blind placebo-controlled, cross-over design. A control group of healthy women was studied once without any treatment., Measurements: Before and after each treatment period, blood was sampled for measurement of androgens, IGF-I, IGFBP-3 and GHBP. A 24-h GH profile with measurements every 20 min was performed at the end of each period., Results: DHEA supplementation normalized the mean circulating levels of testosterone and androgen precursors. The secretory pattern of GH was unaltered during DHEA [placebo vs. DHEA; half-life 22.83 +/- 1.24 vs. 21.45 +/- 1.19 (min), P = 0.429; pulse frequency 9.9 +/- 0.7 vs. 10.5 +/- 0.5 (/24 h), P = 0.502; total production rate 62.27 +/- 13.44 vs. 52.61 +/- 7.06 (microg/l/day), P = 0.317]. Subgroup analysis, however, indicated that DHEA treatment increased GH secretion in patients not receiving oestrogen (n = 5), whereas the opposite was observed among patients receiving exogenous oestrogen derivatives (n = 5). Compared to the control group (CON), GH half-life was longer in AF (half-life CON: 16.48 +/- 0.91, P = 0.001). The additional features of GH secretion were similar. Unexpectedly, the levels of IGF-I, IGFBP-3 and GHBP were elevated in the patients as compared to controls, without significant effects of DHEA [AF vs. CON. IGF-I: 186 +/- 20 vs. 144 +/- 7 (microg/l), P = 0.04; IGFBP-3: 5196 +/- 224 vs. 3687 +/- 212 (microg/l), P = 0.001; GHBP: 2.27 +/- 0.25 vs. 1.41 +/- 0.13 (nmol/l), P = 0.002]., Conclusion: (1) Short-term DHEA administration in women with adrenal failure normalizes the circulating levels of androgens without uniformly affecting the GH-IGF axis; (2) The observation that exogenous oestradiol may mask a stimulatory effect of DHEA on GH secretion merits future investigation.

Background: Madin-Darby canine kidney (MDCK) cells are immortalized epithelial cells that have been used extensively as a model system to study intracellular molecular trafficking, polarized expression, and secretion of proteins in various epithelia. In order to determine if MDCK cells might serve as a model to study molecular events within prostate epithelial cells, we have evaluated the polarized distribution of three prostate restricted proteins, PSMA, PSCA, and PSA, in situ, and in MDCK cells., Methods: Using immunofluorescence, confocal microscopy, cell surface biotinylation, antibody internalization, and biochemical assays we evaluated surface expression and secretion of three prostate restricted proteins expressed in MDCK cells. We compared these patterns of expression to results observed within prostatic epithelium., Results: We demonstrate that PSMA is localized primarily to the apical plasma membrane in both the prostatic epithelium and transfected MDCK cells, whereas PSCA is expressed in a non-polarized fashion. We also show that PSA is secreted predominantly from the apical surface of transfected MDCK cells, consistent with in vivo observations., Conclusions: Similar patterns of localization among MDCK and prostatic epithelial cells suggest that the mechanisms of polarized sorting within these cell types are conserved. Thus, MDCK cells offer a useful model system to study mechanisms of targeting of these proteins within the prostate., (Copyright 2003 Wiley-Liss, Inc.)

Objective: To investigate the impact of age on the association between the respiratory quotient (RQ) and growth-hormone (GH) secretion and to investigate the acute lipolytic response to an exogenous GH bolus., Research Methods and Procedures: A cross-sectional study of 36 non-obese healthy subjects (18 women and 18 men) from two age groups was used: "younger" (mean age, 29.5 years; range, 27 to 34 years) and "older" (mean age, 50.8 years; range, 47 to 59 years). Endogenous GH secretion by means of deconvolution analysis of 24-hour serum GH concentrations was measured every 20 minutes. Resting RQ was measured after a 12-hour overnight fast. The lipolytic response to an intravenous exogenous GH bolus (200 microg) was assessed by measuring serum levels of free fatty acids as well as changes in RQ. Additional measurements included body composition (regional computed tomography scan and DXA) and physical fitness (VO(2)max)., Results: Resting RQ did not differ between the two age groups: 0.81 +/- 0.01 (young) vs. 0.82 +/- 0.01 (older; not significant). Several estimates of GH release correlated positively with RQ in the younger group, whereas a negative correlation was detected in the older subjects [GH production rate (microg/liter x kg) vs. RQ: r = 0.62, p < 0.01 (younger); r = -0.53; p = 0.02 (older)]. By regression analysis, 52% to 58% of the variation in RQ could be explained by GH status. After an exogenous GH bolus, the incremental response in nonesterified fatty acid was slightly higher in younger individuals (p = 0.09)., Discussion: Resting RQ is significantly correlated with GH status. This association is positive in younger individuals and negative in older individuals. The lipolytic response to exogenous GH is moderately higher in younger compared with older individuals. GH status should be taken into account when investigating the residual variation in RQ.

We report a case of severe primary hyperparathyroidism in a 38 year-old female reporting only vague symptoms. Serum PTH at the time of diagnosis was 201 pmol/l. A palpable, encapsulated chief cell adenoma weighing 25.5 grams was removed and the hyperparathyroidism resolved.

Background: It has previously been suggested that epidermal growth factor (EGF) plays a role in the function of the ovary. We administered systemic EGF to assess the influence of EGF receptor stimulation on the morphology of the ovaries., Methods: Forty-eight female Wistar rats were allocated to five groups receiving EGF treatment (150 microgram/kg/day) for 0 (controls), 1, 2, 3 and 4 weeks. All rats were exactly 8 weeks at the start of the experiment and 12 weeks at sacrifice. The EGF was administered in the weeks prior to sacrifice. At sacrifice, the perfusion-fixed ovaries were removed and weighed, and the volumes of tissue components were quantified using stereology., Results: EGF administration increased the total weight of the ovaries from 129 +/- 18 mg in the controls to 158 +/- 29 mg (p<0.05) after one week. In subsequent weeks the total weight increased to 230 +/- 73 mg (p<0.001). The weight gain after one week of treatment was exclusively due to a fourfold increase in follicular cyst volume (p<0.01). In subsequent weeks the cyst volume was increased up to eightfold. After 2, 3 and 4 weeks of treatment the quantity of luteinizing cells was likewise increased by 70% (p<0.01)., Conclusion: EGF administration causes the follicular cells to produce cysts and increases the quantity of luteinizing cells.

Angiotensin-converting enzyme (ACE) is identical to kinase II, which inactivates bradykinin. Inhibition of bradykinin degradation by ACE inhibitors alters the kinin-kallikrein arachidonic acid system leading to increased concentrations of inflammatory metabolites. It has previously been demonstrated that the arachidonic acid system may play a role in the pathogenesis of psoriasis/volar pustulosis. Our patient was treated with Captopril and developed a rash identical to volar pustulosis within six weeks. Captopril was substituted with Perindopril, and the eruptions had almost disappeared five months later after a short systemic treatment with steroids. One month later the patient developed the same rash. Perindopril was withdrawn and the eruptions had disappeared two months later.