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Endocrinopathies are frequently the initial presentation of histiocytic neoplasms, which are rare hematologic disorders affecting multiple organ systems. Langerhans cell histiocytosis and Erdheim-Chester disease are 2 such disorders known to infiltrate the hypothalamus and/or pituitary gland, leading to arginine vasopressin deficiency (AVP-D) and anterior pituitary dysfunction (APD) in 20% to 30% of cases, often as the first manifestation. Conversely, histiocytic disorders account for a notable proportion (10-15%) of all pituitary stalk lesions. The diagnosis of histiocytoses is often delayed in such cases due to the nonspecific presentation of endocrinopathies and pituitary involvement. Consequently, endocrinologists are at the frontline and uniquely positioned to achieve early diagnosis by recognizing the varied nonendocrine features of these disorders. This article provides an overview of the endocrine manifestations of histiocytic disorders and presents a simplified algorithm to guide the diagnostic workup in cases presenting with "idiopathic" AVP-D or APD. Such cases should be evaluated for histiocytic neoplasms with additional imaging studies and biopsies of suspected disease sites. If no disease site beyond the pituitary is identified, the risks and benefits of a pituitary stalk lesion biopsy must be carefully considered. While treatments of histiocytic neoplasms are highly efficacious, endocrinopathies are considered permanent and require long-term hormone replacement. It remains unclear whether early diagnosis and novel targeted therapies can reverse these endocrine disorders. Therefore, the role of the endocrinologist role is critical in the diagnosis and management of these rare diseases., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com. See the journal About page for additional terms.)

Context: Diabetic ketoacidosis (DKA) in pregnancy is an obstetric emergency with risk of maternofetal death., Objective: This work aimed to evaluate DKA events in pregnant women admitted to our inpatient obstetric service, and to examine associated clinical risk factors, presentation, and pregnancy outcomes., Methods: A retrospective cohort study was conducted at the Mayo Clinic, Rochester, Minnesota, USA, and included women aged 17 to 45 years who were treated for DKA during pregnancy between January 1, 2004 and December 31, 2021. Main outcome measures included maternal and fetal death along with a broad spectrum of maternal and fetal pregnancy outcomes., Results: A total of 71 DKA events were identified in 58 pregnancies among 51 women, 48 (82.8%) of whom had type 1 diabetes. There were no maternal deaths, but fetal demise occurred in 10 (17.2%) pregnancies (6 miscarriages and 4 stillbirths). Maternal social stressors were frequently present (n = 30, 51.0%), and glycemic control was suboptimal (median first trimester glycated hemoglobin A1c = 9.0%). Preeclampsia was diagnosed in 17 (29.3%) pregnancies. Infants born to women with DKA were large for gestational age (n = 16, 33.3%), suffered from neonatal hypoglycemia (n = 29, 60.4%) and required intensive care unit admission (n = 25, 52.1%)., Conclusion: DKA is associated with a high rate of maternofetal morbidity and fetal loss. Prenatal education strategies for women with diabetes mellitus should include a strong focus on DKA prevention, and clinicians and patients should have a high index of suspicion for DKA in all pregnant women who present with symptoms that could be attributed to this condition., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objectives: Assessment of surgical outcome in acromegaly is typically recommended at 3 to 6 months following surgery. The purpose of this study was to determine if insulin-like growth factor 1 (IGF-1) concentrations at 6 weeks were equally predictive of surgical outcomes compared with IGF-1 concentrations at 3 to 6 months postoperatively applying newer IGF-1 assays., Methods: Retrospective review of patients with newly diagnosed acromegaly who had surgery between 2013 and 2020 and had postoperative IGF-1 measured by 6 weeks and 3 to 6 months., Results: At 6 weeks, 20 (35%) of the total 57 had normal IGF-1 and became abnormal in 1 at 3 to 6 months, whereas 37 (65%) of 57 had abnormal IGF-1 concentrations at 6 weeks, which normalized in 1 patient by 3 to 6 months. In patients who changed clinical status, IGF-1 at 6 weeks was within ±0.1-fold of normal. Although a difference was seen between median IGF-1 concentrations (286 vs 267 ng/mL, P = .009) at 6 weeks and 3 to 6 months, the mean reduction was small (-19.9 ng/mL)., Conclusions: Compared with 3 to 6 months, use of IGF-1 at 6 weeks was associated with a change in clinical status in 3.5% of patients. Therefore, in most patients, IGF-1 at 6 weeks can be used to assess clinical outcome via newer assays., (© American Society for Clinical Pathology, 2021. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Context: Lymphocytic hypophysitis (LyHy) is characterized by inflammation of the pituitary and or neuroinfundibulum and is uncommon. Treatment options include observation, high-dose glucocorticoids (HD-GCs) or surgery. Optimal first-line management strategy, however, remains unknown., Objective: This work aimed to assess response to first-line treatment options (observation, HD-GCs, or surgery) of clinically relevant outcomes (symptomatic, hormonal, and radiographic improvement) among patients with LyHy., Methods: A systematic review was conducted in 6 databases through 2020. Meta-analysis was conducted when feasible using a random-effects model., Results: We included 33 studies reporting on 591 patients (423 women, 72%) with LyHy. Improvement/resolution of anterior pituitary dysfunction was highest when HD-GCs was first-line treatment. Surgery was associated with the greatest proportion of patients who had regression on imaging. Subgroup analysis comparing HD-GCs to observation showed the odds of anterior pituitary hormone recovery (OR 3.41; 95% CI, 1.68-6.94) or radiographic regression (OR 3.13; 95% CI, 1.54-6.36) were higher with HD-GCs, but so was the need for additional forms of treatment (OR 4.37; 95% CI, 1.70-11.22). No statistically significant difference was seen in recovery of diabetes insipidus (OR 0.9; 95% CI, 0.26-3.10). Certainty in these estimates was very low., Conclusion: Observation and use of HD-GCs both are successful first-line management strategies in LyHy. Although use of HD-GCs was associated with increased recovery of anterior pituitary hormone deficit, it also was associated with greater likelihood of additional treatment after withdrawal. Optimal dosing and duration of HD-GCs remains unknown., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Aedes albopictus (Skuse), an invasive disease vector, poses a nuisance and public health threat to communities in the Northeastern United States. Climate change and ongoing adaptation are leading to range expansion of this mosquito into upstate New York and other northeastern states. Organized mosquito control can suppress populations, but it is time consuming, costly, and difficult as Ae. albopictus oviposits in small, artificial, water-holding containers. Unmanned aerial vehicles (UAVs), with centimeter-resolution imaging capabilities, can aid surveillance efforts. In this work, we show that a convolutional neural network trained on images from a UAV is able to detect Ae. albopictus habitat in suburban communities, and the number of containers successfully imaged by UAV predicted the number of containers positive for mosquito larvae per home. The neural network was able to identify some, but not all, potential habitat, with up to 67% precision and 40% recall, and can classify whole properties as positive or negative for larvae 80% of the time. This combined approach of UAV imaging and neutral network analysis has the potential to dramatically increase capacity for surveillance, increasing the reach and reducing the time necessary for conventional on-the-ground surveillance methods., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Context: Testosterone (T) increases GH secretion in older men with a relative lack of T, in hypogonadal men of all ages, and in patients undergoing sex reassignment. The role of estradiol (E2) in men is less well defined., Objective: To assess the contribution of aromatization of T to spontaneous nocturnal and stimulated GH secretion., Participants: Four groups of healthy older men (N = 74, age range 57 to 77 years) were studied. The gonadotropic axis was clamped with the gonadotropin-releasing hormone antagonist degarelix. Three groups received T and one group placebo addback. Two T-replaced groups were treated with anastrozole (an aromatase inhibitor) and either placebo or E2 addback., Main Outcome Measures: Ten-minute GH concentration profiles were quantified by deconvolution analysis, after overnight (2200 to 0800 hours) sampling, and after combined IV injection of GHRH (0.3 µg/kg) and GHRH-2 (0.3 µg/kg) and withdrawal of a 2-hour somatostatin infusion (1 µg/kg/h)., Results: E2 addback during aromatase inhibition increased basal (P = 0.046), pulsatile (P = 0.020), and total (P = 0.018) GH secretion by 60% to 70%. E2 did not potentiate GH secretory stimuli. Logarithmically transformed pulsatile GH secretion correlated strongly and positively with concurrent E2 concentrations overall (P = 0.028) and under anastrozole treatment (P = 0.005)., Conclusion: E2 administration in older men transdermally stimulates overnight pulsatile GH secretion. The exact site of E2 action cannot be ascertained from these experiments but may include hypothalamic loci involved in GH regulation, especially because GH secretagogue effects on somatotrope pituitary cells were not affected.

Background: Previously defined thresholds for total testosterone (TT) concentrations to screen for androgen-producing tumors (APTs) have used RIA, which can be less accurate in women. We aimed to define diagnostic thresholds to screen for APTs or postmenopausal pathologic hyperandrogenism using TT concentrations measured by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)., Methods: We performed a retrospective cohort study on all women with TT ≥3.5 nmol/L and all postmenopausal women presenting with hyperandrogenism between 2004 and 2014 at the Mayo Clinic in Rochester, MN., Results: Of the 369 women with TT ≥3.5 nmol/L, 89 were included and subdivided into 3 groups based on their clinical diagnosis [21 (24%), APT; 16 (18%), postmenopausal pathologic hyperandrogenism; 52 (58%), polycystic ovary syndrome]. The source of the APT was more frequently ovarian (81%, n = 17) than adrenal (19%, n = 4). The diagnostic threshold using ROC analysis for TT to identify APT in women with severe biochemical hyperandrogenemia was ≥5.1 nmol/L (sensitivity, 90%; specificity, 81%). In a second analysis of a cohort of postmenopausal women only presenting with symptoms or signs of hyperandrogenism, median TT was significantly higher in the postmenopausal pathologic hyperandrogenism group (APT and ovarian hyperthecosis) vs the idiopathic hyperandrogenism group (4.9 vs 0.8 nmol/L; P < 0.01). In postmenopausal women, the diagnostic threshold for pathologic hyperandrogenism was TT ≥2.2 nmol/L (sensitivity, 100%; specificity, 86%)., Conclusions: The diagnostic threshold for TT concentration as measured by LC-MS/MS to identify APT in women with biochemical severe hyperandrogenemia was TT ≥5.1 nmol/L. In postmenopausal women, the diagnostic threshold for pathologic hyperandrogenism was lower (TT ≥2.2 nmol/L)., (© 2018 American Association for Clinical Chemistry.)

Background: Adrenocorticotropic hormone (ACTH) secretion is controlled by unobservable hypothalamic corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP) pulses. Clamping exogenous CRH or AVP input could allow indirect quantification of the impact of the endogenous heterotypic hormone., Methods: We conducted a randomized, double-blind, placebo-controlled, crossover study in 28 healthy adults (16 men). Volunteers underwent a sex-steroid clamp and a cortisol clamp. ACTH was measured over 10 hours by 10-minute sampling during each of four randomized intravenous (IV) secretagogue clamps (i.e., continuous IV CRH, AVP, both peptides, or saline). Desensitization was tested by bolus injection of the noninfused peptide., Results: Mean ± standard error of the mean 10-hour ACTH concentrations (ng/L) in the sex-combined analysis were: saline, 32 ± 4.6; AVP, 29 ± 4.6; CRH, 67 ± 6.2; and CRH-AVP, 67 ± 8.8 (any CRH vs AVP or saline, P < 0.0001). CRH and AVP increased approximate entropy (relative randomness) of ACTH release (P < 0.0001). Bolus AVP injection after CRH infusion yielded a 2.5-hour ACTH concentration of 46 ± 4.3, exceeding that seen after bolus CRH or saline injection (26 ± 3.3 and 24 ± 3.6, respectively; P = 0.002 and 0.001). Sex hormone clamps did not influence ACTH levels., Conclusions: A CRH, but not AVP, clamp yields sustained pulsatile ACTH secretion with high ACTH secretory-burst mass and randomness. After 10-hour CRH infusion, bolus AVP but not CRH, evoked marked ACTH release, likely caused by heterotypic sensitization of corticotropes by CRH. Similar interactions might underlie chronic stress states., (Copyright © 2017 Endocrine Society)

Objective: Beneficial effects of adrenalectomy on cardiovascular risk factors in patients with subclinical Cushing's syndrome (SCS) are uncertain. We sought to conduct a systematic review and meta-analysis with the following objectives: (i) determine the effect of adrenalectomy compared with conservative management on cardiovascular risk factors in patients with SCS and (ii) compare the effect of adrenalectomy on cardiovascular risk factors in patients with SCS vs those with a nonfunctioning (NF) adrenal tumor., Methods: MEDLINE In-Process & Other Non-Indexed Citations, MEDLINE, EMBASE and Cochrane Central Register of Controlled Trial were searched on 17 November 2015. Reviewers extracted data and assessed methodological quality in duplicate., Results: We included 26 studies reporting on 584 patients with SCS and 457 patients with NF adrenal tumors. Studies used different definitions of SCS. Patients with SCS undergoing adrenalectomy demonstrated an overall improvement in cardiovascular risk factors (61% for hypertension, 52% for diabetes mellitus, 45% for obesity and 24% for dyslipidemia). When compared with conservative management, patients with SCS undergoing adrenalectomy experienced improvement in hypertension (RR 11, 95% CI: 4.3-27.8) and diabetes mellitus (RR 3.9, 95% CI: 1.5-9.9), but not dyslipidemia (RR 2.6, 95% CI: 0.97-7.2) or obesity (RR 3.4, 95% CI: 0.95-12). Patients with NF adrenal tumors experienced improvement in hypertension (21/54 patients); however, insufficient data exist for comparison to patients with SCS., Conclusions: Available low-to-moderate-quality evidence from heterogeneous studies suggests a beneficial effect of adrenalectomy on cardiovascular risk factors in patients with SCS overall and compared with conservative management., (© 2016 European Society of Endocrinology.)

Background: Systemic concentrations of T, estradiol (E 2 ), GH, IGF-1, and IGF binding protein-3 decline in healthy aging individuals. Conversely, T and E 2 stimulate GH and IGF-1 production in hypogonadal patients., Hypothesis: Because E 2 stimulates GH secretion, putatively via the nuclear estrogen receptor-α and E 2 and GH fall with menopause, we postulated that diminished endogenous E 2 contributes to low GH output in older women., Location: The study was conducted at the Mayo Center for Clinical and Translational Science., Study Design: This was a randomized, double-blind, controlled study in 60 healthy postmenopausal women treated with the following: 1) double placebo; 2) anastrozole, a potent inhibitor of aromatase-enzyme activity, which mediates E 2 synthesis from T; and/or 3) fulvestrant, a selective estrogen receptor-α antagonist., Methods: GH pulse generation was quantified by frequent GH sampling before and after short-term iv somatostatin infusion, thought to induce hypothalamic GHRH-mediated rebound-like GH secretion., Results: On anastrozole, E 2 fell from 3.1 ± 0.35 pg/mL to 0.36 ± 0.04 pg/mL, and estrone from 13 ± 1.4 pg/mL to 1.9 ± 0.01 pg/mL (P < .001) by mass spectrometry. Estrogen values were unchanged by fulvestrant. T concentrations did not change. One-hour peak GH rebound after somatostatin infusion declined markedly during both estrogen-deprivation schedules (P < .001). Mean (150 min) maximal GH rebound decreased comparably (P < .001). Measures of GH rebound correlated negatively with computed tomography-estimated abdominal visceral fat (all P < .05)., Conclusion: These data suggest a previously unrecognized dependence of hypothalamo-pituitary GH regulation on low levels of endogenous estrogen after menopause.

Context: Hyposomatotropism in healthy aging women reflects in part physiological estrogen (estradiol [E2]) depletion associated with menopause., Objective and Design: The purpose of this study was to test the hypothesis that low concentrations of endogenous E2 after menopause continue to drive GH secretion., Setting: The study was performed at the Mayo Center for Clinical and Translational Science., Participants: The participants were 24 postmenopausal women (aged 50-77 years with body mass index of 19-32 kg/m(2))., Interventions: This was a randomized, double-blind, placebo-controlled, parallel-cohort treatment study with placebo (PL) (n = 14) or the antiestrogen fulvestrant (FUL) (n = 10) for 3 weeks, followed by infusion of l-arginine with saline, GHRH, ghrelin, or both peptide secretagogues., Outcomes: GH concentrations were measured over 6 hours with 10-minute sampling and mass spectrometry measures of testosterone, E2, and estrone., Results: Concentrations of testosterone, E2, estrone, SHBG, IGF-I, LH, and FSH were not influenced by antiestrogen treatment. In contrast, GH rose from 0.096 ± 0.018 (PL) to 0.23 ± 0.063 μg/L (FUL, P = .033), and IGF-I binding protein type 3 (IGFBP-3) from 3.6 ± 0.18 to 4.0 ± 2.0 mg/L (P = .041). Conversely, prolactin fell from 7.1 ± 0.69 (PL) to 5.5 ± 0.57 μg/L (FUL) (P = .05), and IGF-I binding protein type 1 (IGFBP-1) fell from 44 ± 9.4 to 27 ± 4.3 μg/L (P = .048). Moreover, FUL vs PL potentiated mean GH responses to l-arginine/saline (P = .007), l-arginine/ghrelin (P = .008), and l-arginine/GHRH + ghrelin (P = .031), but not l-arginine/GHRH., Conclusion: The potent antiestrogen, FUL, amplifies fasting and secretagogue-driven GH secretion and IGFBP-3 concentrations in postmenopausal women without altering SHBG or sex steroid levels. FUL also suppresses prolactin and IGFBP-1, without altering IGF-I. Thus, a major antiestrogen mediates 3 actions of estrogen: agonism (GH), neutral effects (sex steroids), and estrogen antagonism (prolactin and IGFBP-1).

Context: Pituitary involvement in granulomatosis with polyangiitis (GPA) has been described in case reports. The aim of this study was to describe the clinical presentation and outcomes of pituitary disease in patients with GPA evaluated at a tertiary referral center., Setting: A retrospective review of patients with GPA-related pituitary disease seen at the Mayo Clinic in Rochester, Minnesota., Patients: A total of 637 patients with antineutrophil cytoplasmic antibodies-associated vasculitis were followed at our institution from 1996 through 2011. Eight patients (1.3%) with clinically confirmed pituitary involvement formed the basis of this study., Interventions: None., Measurements: Pituitary function was assessed with hormonal testing, including TSH, free T4, cortisol, ACTH, prolactin, FSH, LH, estradiol, T, IGF-1, and simultaneous serum and urine osmolalities., Results: Secondary hypogonadism and diabetes insipidus were the predominant manifestations of pituitary disease (87.5 and 75% of patients, respectively). All patients had abnormal pituitary imaging. A sellar mass with central cystic change and peripheral enhancement was the commonest imaging finding. Pituitary disease was managed with glucocorticoids in combination with cyclophosphamide or rituximab, achieving disease remission in all but one patient. However, permanent anterior pituitary dysfunction was noted in 63% of the patients. Diabetes insipidus was more often reversible, with resolution in 66.7% of the patients., Conclusions: Pituitary involvement in GPA is rare, but it needs to be recognized to avoid unnecessary biopsies of sellar lesions encountered in the context of GPA, and to minimize the risk of irreversible pituitary function loss by prompt implementation of definitive medical therapy for the vasculitis.

The Psychotic Symptom Rating Scales (PSYRATS) is an instrument designed to quantify the severity of delusions and hallucinations and is typically used in research studies and clinical settings focusing on people with psychosis and schizophrenia. It is comprised of the auditory hallucinations (AHS) and delusions subscales (DS), but these subscales do not necessarily reflect the psychological constructs causing intercorrelation between clusters of scale items. Identification of these constructs is important in some clinical and research contexts because item clustering may be caused by underlying etiological processes of interest. Previous attempts to identify these constructs have produced conflicting results. In this study, we compiled PSYRATS data from 12 sites in 7 countries, comprising 711 participants for AHS and 520 for DS. We compared previously proposed and novel models of underlying constructs using structural equation modeling. For the AHS, a novel 4-dimensional model provided the best fit, with latent variables labeled Distress (negative content, distress, and control), Frequency (frequency, duration, and disruption), Attribution (location and origin of voices), and Loudness (loudness item only). For the DS, a 2-dimensional solution was confirmed, with latent variables labeled Distress (amount/intensity) and Frequency (preoccupation, conviction, and disruption). The within-AHS and within-DS dimension intercorrelations were higher than those between subscales, with the exception of the AHS and DS Distress dimensions, which produced a correlation that approached the range of the within-scale correlations. Recommendations are provided for integrating these underlying constructs into research and clinical applications of the PSYRATS., (© The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center.)

Background: To assess the risk of cerebrovascular accidents (CVAs) and second brain tumors (SBTs) in patients with pituitary adenoma after surgery or radiotherapy., Methods: A cohort of 143 people from Olmsted County, who were diagnosed with pituitary adenoma between 1933 and 2000, was studied. Only patients from Olmsted County were included because of the unique nature of medical care in Olmsted County, which allows the ascertainment of virtually all cases of pituitary adenoma for this community's residents and comparisons to the general population in the county. Surgical resection was performed in 76 patients, 29 patients underwent radiotherapy (with 21 undergoing both surgery and radiotherapy), 5 patients were reirradiated, and 59 patients were managed conservatively and observed., Results: Median follow-up was 15.5 years. There was no difference in CVA-free survival between treatment groups. On univariate analysis age > 60 years (hazard ratio [HR], 11.93; 95% CI, 6.26-23.03; P < .001); male sex (HR, 3.67; 95% CI, 2.03-6.84; P < .001), and reirradiation (HR, 3.41; 95% CI, 1.05-9.68; P = .04) were associated with worse CVA-free survival. In multivariate analysis, only age > 60 years was associated with worse CVA-free survival. Compared with the general population, there was a 4-fold increase in the rate of CVAs in pituitary adenoma patients (HR, 4.2; 95% CI, 2.8-6.1). Two patients developed SBT (an irradiated patient and a surgically managed patient)., Conclusion: CVA is a significant risk for patients with pituitary tumors, but treatment does not seem to impact the risk. Even with long-term follow-up, SBTs are a rare event regardless of treatment modality.

Context: Ghrelin is a potent gastric-derived GH-releasing peptide. How ghrelin interacts with sex steroids, GHRH, and somatostatin (SS) is not known., Objective: Our objective was to test the hypotheses that ghrelin's interactions with GHRH (synergistic) and SS (disinhibitory) are ghrelin dose-dependent and amplified by estrogen. SUBJECTS, SETTING, AND DESIGN: Healthy postmenopausal women were treated with placebo (n=12) or 17β-estradiol (E2) (n=12) at the Center for Translational Science Activities in a randomized double-blind prospective study., Methods: Ghrelin dose-dependence was assessed by nonlinear curve fitting of the relationship between deconvolved GH secretory-burst mass and 5 randomly ordered ghrelin doses (0, 0.03, 0.135, 0.6, and 2.7 μg/kg bolus iv) during saline, GHRH, and SS infusion., Results: Under placebo, neither GHRH nor SS altered the ED50 of ghrelin (range 0.64-0.67 μg/kg). Under E2 (median E2 88 pg/mL), the ED50 of ghrelin declined in the presence of GHRH to 0.52 μg/kg. In contrast, the efficacy of ghrelin rose markedly during GHRH vs saline exposure with and without E2: placebo and saline 52±1.0 vs GHRH 173±3.8 μg/L; and E2 and saline 56±0.90 vs GHRH 174±3.7 μg/L. Sensitivity to ghrelin was similar under all conditions., Summary: Short-term E2 supplementation in postmenopausal women reduces the ED50 (increases the potency) of ghrelin when GHRH is present, without altering ghrelin efficacy (maximal effect) or hypothalamo-pituitary sensitivity (slope of dose response) to ghrelin. The data suggest possible physiological interactions among sex steroids (endogenous), ghrelin, and GHRH during E2 replacement in postmenopausal women.

Objective: Estrogen stimulates pulsatile secretion of GH, via mechanisms that are largely unknown. An untested hypothesis is that estradiol (E₂) drives GH secretion by amplifying interactions among GH-releasing hormone (GHRH), somatostatin (SS), and GH-releasing peptide (GHRP)., Design: The design comprised double-blind randomized prospective administration of transdermal E₂ vs placebo to healthy postmenopausal women (n=24) followed by pulsatile GHRH or SS infusions for 13 h overnight with or without continuous GHRP2 stimulation., Methods: End points were mean concentrations, deconvolved secretion, and approximate entropy (ApEn; a regularity measure) of GH., Results: By generalized ANOVA models, it was observed that E₂ vs placebo supplementation: i) augmented mean (13-h) GH concentrations (P=0.023), GHRH-induced pulsatile GH secretion over the first 3 h (P=0.0085) and pulsatile GH secretion over the next 10 h (P=0.054); ii) increased GHRP-modulated (P=0.022) and SS-modulated (P<0.001) GH ApEn; and iii) did not amplify GHRH/GHRP synergy during pulsatile GH secretion. By linear regression, E₂ concentrations were found to be positively correlated with GH secretion during GHRP2 infusion (P=0.022), whereas BMI was found to be negatively correlated with GH secretion during GHRH (P=0.006) and combined GHRH/GHRP (P=0.015) stimulation. E₂ and BMI jointly determined triple (combined l-arginine, GHRH, and GHRP2) stimulation of GH secretion after saline (R²=0.44 and P=0.003) and pulsatile GHRH (R²=0.39 and P=0.013) infusions., Conclusion: In summary, in postmenopausal women, E₂ supplementation augments the amount (mass) and alters the pattern (regularity) of GH secretion via interactions among GHRH, SS, GHRP, and BMI. These outcomes introduce a more complex model of E₂ supplementation in coordinating GH secretion in aging women.

Cells are complex viscoelastic materials that are frequently in deformed morphological states, particularly during the cancer invasion process. The ability to study cell mechanical deformability in an accessible way can be enabling in many areas of research where biomechanics is important, from cancer metastasis to immune response to stem cell differentiation. Furthermore, phenomena in biology are frequently exhibited in high multiplicity. For instance, during metastasis, cells undergoing non-proteolytic invasion squeeze through a multitude of physiological barriers, including many small pores in the dense extracellular matrix (ECM) of the tumor stroma. Therefore, it is important to perform multiple measurements of the same property even for the same cell in order to fully appreciate its dynamics and variability, especially in the high recurrence regime. We have created a simple and minimalistic micropipette system with automated operational procedures that can sample the deformation and relaxation dynamics of single-cells serially and in a parallel manner. We demonstrated its ability to elucidate the impact of an initial cell deformation event on subsequent deformations for untreated and paclitaxel treated MDA-MB-231 metastatic breast cancer cells, and we examined contributions from the cell nucleus during whole-cell micropipette experiments. Finally we developed an empirical model that characterizes the serial factor, which describes the reduction in cost for cell deformations across sequential constrictions. We performed experiments using spatial, temporal, and force scales that match physiological and biomechanical processes, thus potentially enabling a qualitatively more pertinent representation of the functional attributes of cell deformability.

Context: GH negatively regulates its own secretion. How gender, sex steroids, and secretagogues modulate GH autofeedback is not known., Hypothesis/objective: Supplementation with sex steroids and/or a peptidyl secretagogue will enhance the escape of GH from autoinhibition, thus framing a mechanism for amplifying pulsatile GH secretion., Subjects and Setting: Ten healthy postmenopausal women and 10 comparably aged men participated at the Clinical-Translational Science Unit., Design/interventions: Randomly ordered, double-blind, prospective crossover treatment with placebo vs. testosterone (men) or placebo vs. estradiol (women). Autofeedback was imposed by an iv pulse of GH. Recovery of feedback inhibition was quantified during constant infusion of saline, GHRH, or GH-releasing peptide-2 (three peptide categories)., Outcomes/results: During negative feedback, total (integrated) GH recovery depended upon gender (P = 0.017), sex hormone (P < 0.001), and peptide category (P < 0.001). Mechanistic analysis revealed that feedback-suppressed nadir GH concentrations were determined by sex-steroid treatment (P = 0.018) but not by gender (P = 0.444). Peak GH escape was controlled by both treatment (P = 0.004) and gender (P = 0.003). Nadir GH and peak GH during feedback were enhanced by GHRH or GHRP-2 (P < 0.001 for both). Gender × peptide (P = 0.012 for nadir GH), treatment × peptide (P < 0.001 total and peak GH), and gender × treatment (P = 0.017 nadir GH) regulated GH recovery interactively., Conclusion: Gender, sex-steroid supplementation, and secretagogue type confer distinct feedback-rescuing effects, introducing a new level of complexity in the control of pulsatile GH regulation.

Background: GH receptors exist in the hippocampus, cerebral cortex, and hypothalamus, possibly influencing mood, cortical blood flow, and neuronal growth and mediating negative feedback., Rationale: Pegvisomant is a recombinant mutated GH molecule with high affinity, but little or no activating capability, for the GH receptor. It is used clinically as a GH antagonist., Hypothesis: Systemic pegvisomant enters brain interstitial fluid via putative choroid-plexus GH receptors, thereby allowing for antagonism of central actions of GH. SUBJECTS AND LOCATION: Six adults requiring a cerebrospinal fluid (CSF) examination for nonneoplastic and noninflammatory syndromes participated at a tertiary medical center., Methods: Direct assays were conducted of serum and CSF pegvisomant concentrations 18-24 h after sc injection of pegvisomant (20 mg)., Outcomes: Median (range) concentrations of pegvisomant in serum were 215 (74-539) microg/liter and in CSF 0.035 (0.010-0.28) microg/liter (P=0.016). CSF drug levels were indistinguishable from assay threshold. Corresponding GH values were 0.29 (0.010-1.3) in serum and 0.075 microg/liter (0.01-0.13) in CSF. The geometric mean ratios of serum/CSF pegvisomant and GH concentrations were 5116:1 and 3.5:1, respectively, thus defining a more than 1400-fold difference between mutated and natural GH., Conclusions: Based upon CSF measurements, a pegylated GH-receptor antagonist does not cross the human blood-brain barrier, thereby sparing inhibition of central nervous system GH actions. Thus, the capability of this antagonist to stimulate GH secretion predominantly reflects its actions outside the blood-brain barrier, such as via the median eminence and/or via suppression of IGF-I concentrations.

Context: GH-releasing peptide (GHRP), GHRH, and somatostatin are physiological regulators of pulsatile GH secretion., Hypothesis: Age, independently of abdominal visceral fat (AVF) and basal (nonpulsatile) GH secretion, damps pulsatile GH secretion driven by physiological (rather than pharmacological) amounts of GHRP and GHRH in an experimentally controlled estradiol (E(2)) milieu., Design and Setting: A prospectively randomized, double-blind parallel-cohort study was conducted at an academic medical center., Participants: Community-dwelling healthy premenopausal (PRE, age 24 +/- 0.8 yr, n = 20) and postmenopausal (POST, age 63 +/- 1.8 yr, n = 22) women participated in the study., Interventions: Gonadal-axis down-regulation with leuprolide was followed by randomized addback of placebo or transdermal E(2) and separate-day iv bolus injections of a half-maximally stimulatory dose of GHRP-2 or GHRH (each 0.33 mug/kg)., Analysis: Three-way analysis of covariance included main factors age, E(2) status, and secretagogue type and covariates AVF and basal GH secretion., Results: Submaximally stimulated pulsatile GH secretion was positively determined by PRE vs. POST age (P < 0.001), E(2) repletion vs. depletion (P = 0.001) and GHRP-2 vs. GHRH stimulation (P < 0.001), after adjustment for AVF and basal secretion. E(2) vs. placebo elevated fasting mean GH concentrations in both PRE and POST women (P = 0.006) but increased basal (nonpulsatile) GH secretion in PRE only (P = 0.002). PRE vs. POST age prolonged GHRH-driven GH secretory bursts by 36% (P = 0.006)., Conclusion: PRE vs. POST age, E(2) availability, and physiological peptide drive are triple determinants of pulsatile GH secretion independently of abdominal visceral fat and nonpulsatile GH secretion in healthy women.

Context: Women with primary or secondary adrenal insufficiency report a decreased health-related quality of life (HRQOL) despite traditional adrenal replacement therapy. Dehydroepiandrosterone (DHEA) has been studied as an agent to improve HRQOL in these patients., Objective: We sought to conduct a systematic review and meta-analysis of randomized controlled trials of DHEA effects on HRQOL in women with adrenal insufficiency., Data Sources: We searched electronic databases (MEDLINE, EMBASE, Cochrane CENTRAL, Web of Science, CINAHL, and PsycInfo) and reference lists of eligible studies through July 2008., Study Selection: Eligible trials randomly assigned women with primary or secondary adrenal insufficiency to either DHEA or control and measured the effect of treatment on HRQOL., Data Extraction: Reviewers working independently and in duplicate assessed the methodological quality of trials and collected data on patient characteristics, interventions, and outcomes., Data Synthesis: We found 10 eligible trials that measured HRQOL and depression, anxiety, and sexual function. Random-effects meta-analysis showed a small improvement in HRQOL in women treated with DHEA compared with placebo [effect size of 0.21; 95% confidence interval, 0.08 to 0.33; inconsistency (I(2)) = 32%]. There was a small beneficial effect of DHEA on depression; effects on anxiety and sexual well-being were also small and not statistically significant., Conclusions: DHEA may improve, in a small and perhaps trivial manner, HRQOL and depression in women with adrenal insufficiency. There was no significant effect of DHEA on anxiety and sexual well-being. The evidence appears insufficient to support the routine use of DHEA in women with adrenal insufficiency.

Context: The diagnosis of Cushing's syndrome (CS) requires the use of tests of unregulated hypercortisolism that have unclear accuracy., Objective: Our objective was to summarize evidence on the accuracy of common tests for diagnosing CS., Data Sources: We searched electronic databases (MEDLINE, EMBASE, Web of Science, Scopus, and citation search for key articles) from 1975 through September 2007 and sought additional references from experts., Study Selection: Eligible studies reported on the accuracy of urinary free cortisol (UFC), dexamethasone suppression test (DST), and midnight cortisol assays vs. reference standard in patients suspected of CS., Data Extraction: Reviewers working in duplicate and independently extracted study characteristics and quality and data to estimate the likelihood ratio (LR) and the 95% confidence interval (CI) for each result., Data Synthesis: We found 27 eligible studies, with a high prevalence [794 (9.2%) of 8631 patients had CS] and severity of CS. The tests had similar accuracy: UFC (n = 14 studies; LR+ 10.6, CI 5.5-20.5; LR- 0.16, CI 0.08-0.33), salivary midnight cortisol (n = 4; LR+ 8.8, CI 3.5-21.8; LR- 0.07, CI 0-1.2), and the 1-mg overnight DST (n = 14; LR+ 16.4, CI 9.3-28.8; LR- 0.06, CI 0.03-0.14). Combined testing strategies (e.g. a positive result in both UFC and 1-mg overnight DST) had similar diagnostic accuracy (n = 3; LR+ 15.4, CI 0.7-358; LR- 0.11, CI 0.007-1.57)., Conclusions: Commonly used tests to diagnose CS appear highly accurate in referral practices with samples enriched with patients with CS. Their performance in usual clinical practice remains unclear.

Context: The definitive diagnosis of Cushing's syndrome (CS) in the setting of mild disease, as well as exclusion of CS in the setting of conditions that might mimic this clinical entity (pseudo-Cushing's syndrome), continues to present a significant challenge to the clinician., Objective: The aim of the study was to review characteristics of the combined dexamethasone-suppressed CRH stimulation test in patients evaluated at an academic center for the possibility of mild CS., Design, Patients, and Methods: We conducted a retrospective review of 66 patients. A total of 51 patients underwent final statistical analysis: 21 (41%) had Cushing's disease, and 30 were considered to have pseudo-CS based on the clinical scenario, comorbidities, and follow-up. Sensitivity, specificity, and diagnostic accuracy of cortisol and ACTH levels for the diagnosis of Cushing's disease were calculated at 1 min before, and 15, 30, 45, and 60 min after CRH administration. Diagnostic cutoffs for each parameter were determined by minimizing the absolute difference between sensitivity and specificity. Diagnostic accuracy was characterized by the area under the receiver operating characteristic curve, determined using the trapezoid rule., Results: The highest diagnostic accuracy was provided by the serum ACTH level at 15 min post-CRH, in which the area under the receiver operating characteristic curve was 99.7%, and a cutoff of more than 27 pg/ml (>5.9 pmol/liter) provided a sensitivity of 95% and specificity of 97% for the diagnosis of CS. A 15-min post-CRH cortisol greater than 2.5 mug/dl (70 nmol/liter) provided a sensitivity and specificity of 90 and 90%, respectively., Conclusions: Our results differ from previous studies because our data suggest that when using the combined dexamethasone-suppressed CRH stimulation test, a 15-min post-CRH ACTH value greater than 27 pg/ml (5.9 pmol/liter) had the highest diagnostic accuracy for the detection of CS. However, the sensitivity and specificity for this test were not statistically different from the sensitivity and specificity of other tests, such as those measuring post-CRH stimulated ACTH levels or post-CRH cortisol levels at other time points. Therefore, clinicians should be cautious about interpretation of suppression and stimulation tests in the diverse population of patients with hypercortisolism.

Context: Studies of how aging attenuates GH secretion are confounded by differences in sex-steroid milieus, abdominal visceral fat mass (AVF), and IGF-I concentrations and limited in interpretability by the use of pharmacological doses of secretagogues., Hypothesis: In a controlled estrogenic milieu, near-physiological secretagogue drive will unmask distinct influences of age, AVF, and IGF-I on GH secretion., Location: The study was conducted at an academic medical center., Subjects: Subjects included 10 healthy pre- (PRE) and 10 postmenopausal (POST) women., Procedure: In a defined estradiol (E(2)) milieu, we compared GH secretion after submaximal stimulation with GH-releasing peptide (GHRP)-2 (ghrelin analog), GHRH, and l-arginine (an inhibitor of somatostatin outflow)., Analysis: We related GH responses to age stratum (dichotomous variable) and AVF and IGF-I concentrations (continuous variables)., Results: In the face of comparable concentrations of E(2), testosterone, and SHBG: 1) age (P < 0.001) and secretagogue type (P < 0.001) independently determined GH secretion; 2) GH responses in POST subjects were only 26-33% of those in PRE (P < or = 0.002) across all secretagogues; 3) POST women lost the PRE order of secretagogue potency (GHRP-2 > GHRH = l-arginine); and 4) in the combined cohorts, higher AVF predicted reduced l-arginine-stimulated GH secretion (R(2) = 0.46, P = 0.0013), whereas higher IGF-I concentrations forecast increased GHRP-2 and GHRH drive (R(2) > or = 0.52, P < or = 0.013)., Conclusion: A paradigm of near-physiological secretagogue drive in an E(2)-clamped milieu unmasks tripartite deficits in peptide-signaling pathways in healthy POST, compared with PRE, women. Post hoc analyses indicate that both greater visceral adiposity and lower IGF-I concentrations mark this triple regulatory defect.

Background: Aging, body composition, and sex steroids jointly determine GH production. However, the actions of any given factor are confounded by the effects of the other two., Hypothesis: Age and abdominal visceral fat (AVF) mass govern GH secretion via individually distinctive mechanisms, which can be unmasked by short-term sex steroid deprivation., Design/subjects: In a university setting, healthy pre- and postmenopausal volunteers underwent GnRH agonist-induced down-regulation for 6 wk to deplete ovarian sex steroids. GH secretion was evaluated by frequent blood sampling, saline vs. dual secretagogue infusions, an irregularity statistic, variable waveform deconvolution analysis, and a simplified feedback model. Computerized tomography was used to estimate AVF mass. OUTCOMES/MEASURES: In the sex steroid-deficient milieu, postmenopausal compared with premenopausal women exhibited 1) lower concentrations of IGF-I (P = 0.028) and GH (P < 0.05); 2) reduced pulsatile, but elevated basal, GH secretion (P < 0.05); 3) more irregular GH patterns (P = 0.027); 4) an attenuated GH response to simultaneous GHRH/GH-releasing peptide-2 stimulation (P < 0.01); and 5) more rapid onset of GH release within secretory bursts (P < 0.01). In contrast, AVF negatively forecast GH responses to L-arginine/GH-releasing peptide-2 (r2= 0.45; P < 0.001) and L-arginine/GHRH (r2= 0.57; P = 0.007). From these marked contrasts, model-based analyses predicted distinguishable mechanisms by which aging and AVF alter pulsatile GH production., Conclusion: Under limited confounding by sex steroids, age and body composition modulate GH secretion via highly selective peptidyl pathways in healthy women.

The present study tests the hypothesis that estradiol (E(2)), compared with placebo (Pl), amplifies combined-secretagogue stimulation of GH secretion in premenopausal women studied at comparable IGF-I and testosterone concentrations. To this end, 13 women underwent GnRH agonist-induced gonadal down-regulation followed by graded transdermal addback of E(2) or Pl and randomly ordered iv infusions of saline or paired secretagogues on separate morning fasting. GH secretion was assessed by frequent blood sampling, immunochemiluminometry, and variable-waveform deconvolution analysis. Two-way ANOVA revealed that specific secretagogue combination (P < 0.001), E(2) status (P = 0.012), and their interaction (P = 0.038) jointly determined GH secretory-burst mass. Compared with Pl, the E(2)-clamped milieu elevated mean fasting GH concentrations (P = 0.032), the mass of GH secreted in bursts (P = 0.037), and maximal stimulation by paired l-arginine/GH-releasing peptide (GHRP)-2 (P = 0.028). E(2) also markedly accelerated the initial release of GH induced by GHRH/GHRP-2 (P < 0.001) and l-arginine/GHRH (P < 0.01). By linear regression analysis, E(2) concentrations positively forecast 41% of intersubject variability in GH secretion stimulated by combined l-arginine/GHRP-2 (P = 0.018), whereas abdominal visceral-fat mass negatively predicted 49% of that due to l-arginine/GHRH (P = 0.012). These data indicate that pulsatile GH secretion in young women studied at constant IGF-I and testosterone concentrations is dictated 3-fold jointly by secretagogue pair, E(2) availability, and intraabdominal adiposity. Moreover, the rapidity of GH release is controlled 2-fold jointly by E(2) and GHRH.

We show that in an experimentally enforced estradiol-predominant milieu, postmenopausal compared with premenopausal women maintain 1) decreased fasting GH and IGF-I concentrations, 2) reduced basal and pulsatile GH secretion, and 3) attenuated GH secretion after maximal stimulation by the paired secretagogues l-arginine/GH-releasing peptide (GHRP)-2, l-arginine/GHRH, and GHRP-2/GHRH. These foregoing outcomes are selective, because menopausal status did not determine mean GH secretory-burst frequency or peptide-induced waveform shortening. Abdominal visceral fat mass predicted up to 25% of the variability in fasting and stimulated GH secretion in the combined cohorts under fixed systemic estradiol availability. Accordingly, as much as three-fourths of interindividual differences in burst-like GH secretion among healthy pre- and postmenopausal women arise from age-related mechanisms independently of short-term systemic estrogen availability and relative intraabdominal adiposity.

Paragangliomas are rare tumors that arise from extraadrenal chromaffin cells. We examined the clinical characteristics, location, treatment, and outcome of 236 patients (141 females, 60%) with 297 benign paragangliomas evaluated at the Mayo Clinic during 1978-1998. The mean age (+/-SD) at diagnosis was 47 +/- 16 yr. Of the 297 paragangliomas, 205 were in the head and neck region, and 92 were below the neck. Paragangliomas were discovered and diagnosed incidentally on imaging studies in 9% of patients. Biochemical screening was performed in 128 patients; 40 patients (17% of the total and 31% of those screened) had hyperfunctional tumors. Of the 40 patients with tumoral catecholamine excess, 38 had documented hypertension. In patients identified with catecholamine-secreting paragangliomas, the sensitivities achieved by measurements in the 24-h urine collection were 74% for total metanephrines, 84% for norepinephrine, 18% for dopamine, and 14% for epinephrine. Multiple imaging modalities were used for tumor localization. The false negative rates were 0% for magnetic resonance imaging, 5.8% for computed tomography, 3.4% for angiography, 10.7% for ultrasonography, and 39% for radioactive iodine-labeled metaiodobenzylguanidine scintigraphy. Of 192 patients (81.4%) with follow-up data (mean, 43.9 months; range, 0.5-240), operative cure was achieved in 133 (69%). Of the 59 patients without cure, 23 had persistent disease, 5 had recurrent disease, 16 had multiple persistent synchronous tumors, and 15 subsequently developed metachronous tumors. In conclusion, most paragangliomas are nonhypersecretory and located in the head and neck region. Magnetic resonance imaging was associated with the lowest false negative rate, and metaiodobenzylguanidine was the least sensitive imaging study. A significant proportion of patients (31%) has persistent or recurrent disease, and long-term follow-up is important.

We have analysed the deficiencies of paper medical records in facilitating the care of patients with diabetes and have developed an electronic medical record that corrects some of them. The diabetes electronic medical record (DEMR) is designed to facilitate the work of a busy diabetes clinic. Design principles include heavy reliance on graphic displays of laboratory and clinical data, consistent color coding and aggregation of data needed to facilitate the different types of clinical encounter (initial consultation, continuing care visit, insulin adjustment visit, dietitian encounter, nurse educator encounter, obstetric patient, transplant patient, visits for problems unrelated to diabetes). Data input is by autoflow from the institutional laboratories, by desk attendants or on-line by all users. Careful attention has been paid to making data entry a point and click process wherever possible. Opportunity for free text comment is provided on every screen. On completion of the encounter a narrative text summary of the visit is generated by the computer and is annotated by the care giver. Currently there are about 7800 patients in the system. Remaining challenges include the adaptation of the system to accommodate the occasional user, development of portable laptop derivatives that remain compatible with the parent system and improvements in the screen structure and graphic display formats.