Sex-specific echocardiographic phenotypes in left ventricular outflow tract obstruction

Funding Acknowledgements

Type of funding sources: None.

Background

Previous studies have reported major sex differences in prevalence, demographics, and timing of intervention in left ventricular outflow tract (LVOT) obstruction. Whether the observed differences are related to LVOT anatomy is less explored.

Purpose

The aim of this study was to assess the anatomic substrate for LVOT obstruction by echocardiography to identify sex-specific phenotypes.

Methods

We included 76 patients (37% women) with symptomatic LVOT obstruction referred to a tertiary care centre between 2005-2020 to be considered for septal ablation or myectomy. A standardized echocardiography was extended with systematic measurements of parasternal LVOT dimensions at 5, 10 and 15 mm below the aortic valve, proximal septal thickness at 10, 20 and 30 mm, subaortic septal bulge radius and aortoseptal angle in all patients prior to intervention (Image). Measurements were also adjusted for body surface area (BSA). A total of 3 patients had to be excluded from analysis due to poor image quality.

Results

Women were older (p < 0.001, Table), while there were no differences in body mass index (27.6 v.s. 27.5, p = ns), systolic and diastolic blood pressure (133 v.s 133 mmHg, p = ns and 75 v.s 80 mmHg, p = ns, respectively), or prevalence of hypertension (24% v.s. 29%, p = n.s). Left ventricular end-diastolic diameter, LVOT diameters and septum thickness measured 30 mm from the aortic valve were lower in women (Table). However, in all these measurements the differences disappeared after adjusting for BSA. There were no sex differences in posterior wall thickness. Furthermore, the aortoseptal angle was steeper among women, and the septum bulge radius smaller, remaining so even after adjustment for BSA(Table).

Conclusion

In women with LVOT obstruction, the septum bulge radius adjusted for BSA was smaller, and the aortoseptal angle steeper. Our findings suggest that there may be important sex differences in the echocardiographic phenotype in LVOT obstruction. Abstract Table  Abstract Figure. Image

Comparison of MICRO-ID Listeria Method with Conventional Biochemical Methods for Identification of Listeria Isolated From Food and Environmental Samples: Collaborative Study

Fourteen laboratories participated in a collaborative study to evaluate the ability of the MICRO-ID Listeria identification method to correctly identify Listeria isolated from food and environmental sources. Each collaborator received 60 isolates consisting of 51 Listeria and 9 non-Listeria cultures. All isolates were identified by conventional biochemical analyses in the principal laboratory. Cultures were checked for purity by Gram staining and examined for oxidase and catalase activities. Only Gram positive, oxidase negative, catalase positive cultures were tested with the method. Colonies from trypticase soy agar with 0.6% yeast extract were suspended in 4.6 ml_ physiological saline to a MacFarland No. 1 turbidity standard and used to inoculate the test strip. In addition, the hemolytic reaction of each isolate was determined by using the Christie-Atkins-Munch-Peterson (CAMP) test and by stabbing sheep blood agar. Identification of Listeria is based on the octal code obtained from the strip and the hemolytic reaction of the isolate. The MICRO-ID Listeria method agreed with conventional biochemical identification for 98.0% of L. monocytogenes, 77.1% of L. seeligeri, 98.0% of L ivanovii, 96.4% of L. grayi/L. murrayi, 73.9% of L. welshimeri, and 100% of L innocua isolates. A large percentage of errors in identification of the L. seeligeri and L ivanovii cultures was caused by inaccurate reading of the CAMP and hemolysis tests rather than errors in the test strip. The method was adopted first action by AOAC International.

Inanspruchnahme des psychosozialen Hilfesystems bei jungen, psychisch erkrankten Arbeitslosengeld-II-Empfängern vor und nach Nutzung eines psychiatrisch-psychologischen Beratungsangebotes

Ziel der Studie: Erfassung der Inanspruchnahme des Hilfesystems bei psychisch erkrankten 16–24-jähriger Arbeitslosengeld-II-Empfängern vor und nach der Nutzung eines psychiatrisch-psychologischen Beratungsangebotes („Support 25“).

Methodik: Längsschnittliche Erfassung der Inanspruchnahme zu 3 Messzeitpunkten über insgesamt 9 Monate (N=148); Messung möglicher Einflussfaktoren mittels Selbst- und Fremdratinginstrumenten.

Ergebnisse: Die Inanspruchnahme verdoppelte sich nach Erhalt einer Behandlungsempfehlung auf 40% nach 3 Monaten bzw. 47,5% nach 6 Monaten. Inhaltlich dominierte die Nutzung niederschwelliger psychosozialer Beratungsangebote gegenüber primär psychiatrisch-psychotherapeutischen Behandlungen. Probanden, die sich in Beratung/Behandlung begeben hatten, wiesen tendenziell ein niedrigeres allgemeines Funktionsniveau auf als Probanden ohne Inanspruchnahme. Stigma-Faktoren behinderten die Einmündung in Beratung/Behandlung nicht.

Schlussfolgerungen: Die hier untersuchten jungen Arbeitslosengeld-II-Empfänger hatten – trotz ausgeprägter psychiatrischer Morbidität – Schwierigkeiten, in Behandlungsangebote einzumünden. Obwohl sich nach erfolgter Aufklärung über Diagnosen und Behandlungsmöglichkeiten die Inanspruchnahme verbesserte, dominierten weiterhin niederschwellige Beratungsangebote. Dies könnte darauf hindeuten, dass sich das primär psychiatrisch-psychotherapeutische Hilfesystem besser an die besonderen Bedürfnisse der Zielgruppe anpassen muss, z. B. durch die Ausweitung spezifischer psychoedukativer Angebote an Jobcentern.

Mitochondrial coupling and capacity of oxidative phosphorylation in skeletal muscle of Inuit and Caucasians in the arctic winter

During evolution, mitochondrial DNA haplogroups of arctic populations may have been selected for lower coupling of mitochondrial respiration to ATP production in favor of higher heat production. We show that mitochondrial coupling in skeletal muscle of traditional and westernized Inuit habituating northern Greenland is identical to Danes of western Europe haplogroups. Biochemical coupling efficiency was preserved across variations in diet, muscle fiber type, and uncoupling protein-3 content. Mitochondrial phenotype displayed plasticity in relation to lifestyle and environment. Untrained Inuit and Danes had identical capacities to oxidize fat substrate in arm muscle, which increased in Danes during the 42 days of acclimation to exercise, approaching the higher level of the Inuit hunters. A common pattern emerges of mitochondrial acclimatization and evolutionary adaptation in humans at high latitude and high altitude where economy of locomotion may be optimized by preservation of biochemical coupling efficiency at modest mitochondrial density, when submaximum performance is uncoupled from VO2max and maximum capacities of oxidative phosphorylation.

Gamma ray measurements with photoconductive detectors using a dense plasma focus

Photons in the MeV range emitted from the dense plasma focus (DPF) at the NSTec North Las Vegas Facility have been measured with both neutron-damaged GaAs and natural diamond photoconductive detectors (PCDs). The DPF creates or "pinches" plasmas of various gases (e.g., H2, D2, Ne, Ar., etc.) that have enough energy to create MeV photons from either bremsstrahlung and/or (n,n(')) reactions if D2 gas is used. The high bandwidth of the PCDs enabled the first ever measurement of the fast micro-pinches present in DPF plasmas. Comparisons between a slower more conventional scintillator/photomultiplier tube based nuclear physics detectors were made to validate the response of the PCDs to fast intense MeV photon signals. Significant discrepancies in the diamond PCD responses were evident.

Computer-aided diagnosis improves detection of small intracranial aneurysms on MRA in a clinical setting

BACKGROUND AND PURPOSE

MRA is widely accepted as a noninvasive diagnostic tool for the detection of intracranial aneurysms, but detection is still a challenging task with rather low detection rates. Our aim was to examine the performance of a computer-aided diagnosis algorithm for detecting intracranial aneurysms on MRA in a clinical setting.

MATERIALS AND METHODS

Aneurysm detectability was evaluated retrospectively in 48 subjects with and without computer-aided diagnosis by 6 readers using a clinical 3D viewing system. Aneurysms ranged from 1.1 to 6.0 mm (mean = 3.12 mm, median = 2.50 mm). We conducted a multireader, multicase, double-crossover design, free-response, observer-performance study on sets of images from different MRA scanners by using DSA as the reference standard. Jackknife alternative free-response operating characteristic curve analysis with the figure of merit was used.

RESULTS

For all readers combined, the mean figure of merit improved from 0.655 to 0.759, indicating a change in the figure of merit attributable to computer-aided diagnosis of 0.10 (95% CI, 0.03-0.18), which was statistically significant (F(1,47) = 7.00, P = .011). Five of the 6 radiologists had improved performance with computer-aided diagnosis, primarily due to increased sensitivity.

CONCLUSIONS

In conditions similar to clinical practice, using computer-aided diagnosis significantly improved radiologists' detection of intracranial DSA-confirmed aneurysms of ≤6 mm.

Urinary phthalates from 168 girls and boys measured twice a year during a 5-year period: associations with adrenal androgen levels and puberty

BACKGROUND

Little is known about the possible deleterious effects of phthalate exposure on endogenous sex steroid levels in children.

OBJECTIVE

Our objective was to investigate whether urinary phthalate metabolite levels are associated with circulating adrenal androgen levels and age at puberty.

METHODS

This was a longitudinal study of 168 healthy children (84 girls) examined every 6 months for 5 years. Serum levels of dehydroepiandrostenedione sulfate (DHEAS), Δ4-androstenedione, testosterone, and urinary morning excretion of 14 phthalate metabolites, corresponding to 7 different phthalate diesters were determined. A variation in urinary excretion of phthalates was evident in each child, which made a mean of repetitive samples more representative for long-term excretion than a single determination.

RESULTS

We found that girls with excretion of monobutyl phthalate isomers (MBP) and di(2-ethylhexyl) phthalate metabolites above the geometric group mean (795 and 730 ng/kg, respectively) had lower levels of DHEAS and Δ4-androstenedione, although statistically significant only at 13 years of age. In boys, we found that excretion of monobenzyl phthalate above the geometric group mean (346 ng/kg) was associated with lower levels of DHEAS at 11 years of age but higher levels of testosterone at 13 years of age. The same trend was observed for MBP excretion, albeit not statistically significant. A lower age at pubarche was observed in boys with excretion of MBP above the geometric group mean (11.0 vs 12.3 years, P = 0.005).

CONCLUSION

Our data indicate that exposure to dibutyl phthalate isomers (DBP) (in girls) and butylbenzyl phthalate (in boys) are negatively associated with adrenal androgen levels and in boys positively associated with testosterone level at 13 years of age. High exposure to DBP was associated with earlier age at pubarche in boys. In girls, no associations between phthalate exposure and age at pubertal milestones were observed.

[Unequal social participation in later life]

The concept of active ageing comprises the maintenance of societal participation throughout the life span into old age. "Good" ageing in line with this activity paradigm develops into a starting point of social inequality rather than being its result. Based on the German Ageing Survey (DEAS) we investigated access to volunteering and to educational activities depending on social and spatial aspects of inequality. Societal participation is socially and spatially structured. Individuals from a lower social class are less often involved in educational activities or in volunteering. Moreover, individuals living in economically disadvantaged regions are less likely to participate than in economically strong regions. Disadvantages cumulate if low individual resources overlap with poor economic conditions in the living area. Measures to facilitate participation should be taken on the local level to enhance opportunities for volunteering and educational activities. This should help to sustainably increase the participation of individuals from lower social classes.

Similar reference intervals for total testosterone in healthy young and elderly men: results from the Odense Androgen Study

CONTEXT

Ageing in men is associated with changes in levels of sex hormones.

OBJECTIVE

To evaluate differences in sex hormones in young and elderly men and the significance of comorbidity and fat mass on sex hormones in elderly men.

DESIGN

Cross-sectional.

PATIENTS

Seven hundred and eighty-three men aged 20-29 years and 600 men aged 60-74 years randomly recruited from the background population.

MEASUREMENTS

Sex hormones and sex hormone-binding globulin (SHBG) were measured, and reference intervals were determined in healthy individuals in both groups and in elderly men stratified according to whether they were obese or lean (waist circumference ≥102 cm).

RESULTS

Sex hormones were lower and SHBG higher in elderly men compared with the young cohort. Lower cut-offs for total testosterone (TT) in healthy, young and elderly men were similar [Lower cut-off (95% CI): Young: 11·7 (11·2-12·1) vs elderly: 11·2 (10·3-12·1) nmol/l], but lower and higher cut-offs of bioavailable testosterone (BT) and free testosterone (FT) were higher in young men. Higher levels of androgens were found in healthy elderly men compared with those with a chronic disease or obesity. Androgens were inversely associated with central fat mass (CFM), whereas SHBG was inversely and directly associated with CFM and lower extremity fat mass, respectively, in both young and elderly men.

CONCLUSION

Reference intervals for TT were comparable in healthy young and elderly men, but reference intervals for FT and BT were lower in elderly men due to higher levels of SHBG. Androgens and SHBG were lower in elderly men with chronic disease and inversely associated with CFM.

Positive associations between serum levels of IGF-I and subcutaneous fat depots in young men. The Odense Androgen Study

INTRODUCTION

Serum levels of IGF-I are of growing interest due to the associations with morbidity and mortality. Despite markedly suppressed GH secretion, total IGF-I levels are often within normal range in obese adults.

AIM

To study associations between IGF-I and estimated muscle mass in the Odense Androgen Study population and secondly to investigate associations between serum IGF-I and regional fat depots.

METHOD

The Odense Androgen Study is a population-based, cross-sectional study of 776 randomly selected men aged 20-29 years. Regional lean and fat mass were measured by dual-energy X-ray absorptiometry, whereas regional muscle and fat areas were assessed by magnetic resonance imaging.

RESULTS

Age-adjusted IGF-I levels correlated significantly with different estimates of muscle mass (r-values between 0.15 and 0.19; p<0.001). Using multiple linear regression, serum IGF-I correlated positively with subcutaneous adipose tissue on the abdomen (SAT) after controlling for visceral adipose tissue (VAT) in the whole group and in the subgroup of men with normal waist circumference (r-values between 0.13 and 0.15; p<0.03). In addition, IGF-I correlated positively with subcutaneous thigh fat area (TFA) after controlling for intramyocellular lipid (imcl) r=0.18; p<0.004) and IGF-I correlated negatively with TFAimcl in the whole group and in the subgroup of men with normal waist circumference.

CONCLUSION

SAT and subcutaneous TFAs were positively associated with IGF-I in regression analyses. Conversely, imcl of the thigh was inversely associated with IGF-I levels. These findings emphasize the differential associations between IGF-I and regional fat deposits. Future studies may provide further insight regarding the interplay between circulating IGF-I levels and regional muscle and fat mass.

Vitamin D status and PTH in young men: a cross-sectional study on associations with bone mineral density, body composition and glucose metabolism

OBJECTIVE

Although vitamin D and bone metabolism are closely related, few studies have addressed the effects of vitamin D status on bone in men at time of peak bone mass. The objectives of this study were to evaluate the prevalence of vitamin D inadequacy in a cross-sectional study in young men and the effects of vitamin D and parathyroid hormone (PTH) on bone mass, bone markers and metabolic function.

DESIGN AND PARTICIPANTS

The study population consisted of 783 men aged 20-29 years.

MEASUREMENTS

Bone mineral density (BMD) of the total hip, femoral neck and lumbar spine was measured. dual-energy X-ray absorptiometry was used to evaluate total body fat mass (BFAT). Visceral fat mass and abdominal subcutaneous fat mass (ViFM and ScFM) were assessed using magnetic resonance imaging. A radioimmunoassay was used to measure the level of 25-hydroxy vitamin D (25OHD).

RESULTS

The prevalence of vitamin deficiency (serum 25OHD < 50 nm) was 6·3% during summer and 43·6% during winter. Serum 25OHD was associated with BMD at all sites and inversely associated with bone-specific alkaline phosphatase and directly with carboxyterminal telopeptide of type-1-collagen. 25OHD and PTH were inversely associated with BFAT, whereas 25OHD also was inversely associated with body mass index, waist-hip ratio, ViFM and ScFM after adjustment for confounders. The associations were found only to be present in participants with insufficient levels of 25OHD. 25-Hydroxy vitamin D and PTH were inversely related to insulin resistance in vitamin-insufficient participants only. No associations between PTH or 25OHD and blood pressure were noted.

CONCLUSION

The study showed a high prevalence of 25OHD deficiency in young, northern European men, which was significantly associated with decreased BMD. PTH and 25OHD were found to be inversely related to the markers of insulin resistance.

Polymorphisms in the endocannabinoid receptor 1 in relation to fat mass distribution

OBJECTIVE

Both animal and human studies have associated the endocannabinoid system with obesity and markers of metabolic dysfunction. Blockade of the cannabinoid receptor 1 (CB1) caused weight loss and reduction in waist size in both obese and type II diabetics. Recent studies on common variants of the CB1 receptor gene (CNR1) and the link to obesity have been conflicting. The aim of the present study was to evaluate whether selected common variants of the CNR1 are associated with measures of obesity and fat distribution.

DESIGN AND METHODS

The single nucleotide polymorphisms (SNPs) rs806381, rs10485179 and rs1049353 were genotyped, and body fat and fat distribution were assessed by the use of dual-energy X-ray absorptiometry and magnetic resonance imaging in a population-based study comprising of 783 Danish men, aged 20-29 years.

RESULTS

The rs806381 polymorphism was significantly associated with visceral fat mass (FM) only, whereas the rs1049353 was significantly and directly associated with visceral and intermuscular FM. None of the SNPs analysed were associated with total body FM or subcutaneous FM.

CONCLUSION

The results point towards a link between common variants of the CNR1 and fat distribution in young men.

Adiponectin and peak bone mass in men: a cross-sectional, population-based study

Adiponectin, a protein classically known to be secreted by adipocytes, is also secreted by bone-forming cells. Results of previous studies have been contradictory as to whether serum adiponectin and bone mineral density (BMD) are associated. The aim of this study was to investigate a possible association between serum adiponectin and BMD in young, healthy men at a time of peak bone mass. BMD in the femoral neck, total hip, and lumbar spine were measured in this population-based cross-sectional study of 700 men aged 20-29 years participating in the Odense Androgen Study. Magnetic resonance imaging of femoral cortical thickness and bone marrow size was performed in a subsample of 363 participants. The associations between serum adiponectin and various bone measures were investigated by means of regression analyses with adjustment for potential confounding variables. An inverse association was found between serum adiponectin and total hip BMD and a direct between adiponectin and femoral bone marrow size (r = -0.092; P = 0.036 and r = 0.164; P = 0.003, respectively). Femoral muscle size may, at least in part, explain the association between adiponectin and total hip BMD. Serum adiponectin was inversely associated with total hip BMD in men at the time of peak bone mass, but this association may be explained by factors related to muscle size and function. The observed association between adiponectin and femoral bone marrow size was retained even after adjustment for potential covariates.

Temozolomide treatment of a pituitary carcinoma and two pituitary macroadenomas resistant to conventional therapy

OBJECTIVE

Aggressive pituitary tumours may be difficult to treat. Temozolomide (TMZ) is an alkylating cytostaticum. In a small number of cases, TMZ therapy has been reported to reduce pituitary tumour size and hormone hypersecretion.

DESIGN

We present three patients with pituitary tumours treated with TMZ. One tumour was initially a macroprolactinoma that developed into a mixed GH- and prolactin-secreting carcinoma (patient A). To our knowledge, this is the first published in English literature. Two adenomas, a macroprolactinoma (patient B) and a clinically non-functioning pituitary adenoma (patient C), were highly invasive. The three patients suffered from extensive tumour mass effects, and all tumours were resistant to conventional treatment.

METHOD

TMZ, 150-200 mg/m(2) of body surface area was administered orally for 5 days during each 28-day cycle.

RESULT

During TMZ therapy, tumour sizes were significantly reduced, hormone levels normalized and symptoms of mass effects decreased in all three cases. The carcinoma was treated from 2004 to 2006 (23 months). Three years after the terminating treatment, the tumour has not regrown and hormone levels are normalized. Immunohistochemical staining for methylguanine DNA methyltransferase (MGMT) was negative in two patients (A and B), and in one patient (C) a few nuclei stained positive.

CONCLUSION

TMZ therapy significantly decreased tumour volume, hormone hypersecretion and symptoms in all three patients, corresponding to the pathological findings regarding MGMT. TMZ therapy may be a new option for the treatment of resistant pituitary adenomas.

Subcutaneous rather than visceral adipose tissue is associated with adiponectin levels and insulin resistance in young men

INTRODUCTION

Studies on the association between adiponectin, body composition, and insulin resistance (IR) have been conflicting.

AIM

Our aim was to evaluate the impact of body composition on adiponectin and IR determined by homeostasis model assessment (HOMA) in a population-based study on relatively healthy young men, minimizing the possible effects of age, obesity, and severe comorbidity. DESIGN, METHODS, AND SUBJECTS: A population-based, cross-sectional study of 783 men aged 20-29 yr, randomly drawn from the Danish Central Personal Registry. Adiponectin was assessed using an in-house assay, and IR was determined using HOMA. Central fat mass (CFM) and lower extremity fat mass (LEFM) was measured by dual-energy x-ray absorptiometry, and visceral adipose tissue (VAT), sc adipose tissue (SAT), and thigh fat area (TFA) were assessed by magnetic resonance imaging.

RESULTS

Using multiple linear regression analysis, adiponectin correlated negatively with CFM (r = -0.27; P < 0.001) and SAT (r = -0.20; P < 0.001) and positively with LEFM (r = 0.19; P < 0.001) and TFA (r = 0.18; P < 0.001), whereas VAT did not associate significantly. In multiple linear regression analysis, HOMA-IR (dependent variable), correlated significantly with CFM (r = 0.27; P < 0.001) and SAT (r = 0.15; P < 0.001), whereas LEFM, VAT, or TFA did not correlate. Adiponectin was an independent predictor of HOMA-IR in both analyses (r = -0.14; P < 0.001).

CONCLUSION

SAT rather than VAT was inversely associated with adiponectin levels, and, interestingly, fat on the lower extremities was positively associated with adiponectin. Focusing on insulin resistance, SAT rather than VAT and TFA independently predicted a higher HOMA-IR. The observation that adiponectin was independently associated with lower HOMA-IR must be repeated in other populations.

Pituitary-thyroid function and thyrotropin, prolactin and growth hormone responses to TRH in patients with chronic alcoholism

Basal plasma concentrations of thyroxine (T4), 3,3',5-triiodothyronine (T3), free T4 index (TF4I), free T3 index (FT3I) reverse T3, 3,3',5-triiodothyronine (rT3), resin T3 uptake (TR3U), thyroxine-binding globulin (TBG), thyrotropin (TSH), prolactin (PRL) and growth hormone (GH) as well as thyrotropin releasing hormone (TRH) stimulated TSH, PRL and GH were investigated in 31 consecutive male patients (mean age 41 years) with chronic alcoholism. According to the histology of their liver biopsies the patients were divided into three groups: patients with normal livers, steatosis and cirrhosis. The control group consisted of 30 healthy males. The patients had abstained from alcohol for at least one week when studied, and they were on a nutritionally adequate diet. All had consumed a daily minimum of 52 g ethanol for at least 5 years. None of the patients had severe or decompensated liver disease. The patients had significantly reduced T3 and rT3 plasma levels compared to normals. Patients with cirrhosis of the liver had increased TBG and normal RT3U levels, while those without cirrhosis had increased RT3U and normal TBG levels. Plasma concentrations of basal as well as TRH-stimulated TSH and PRL were unchanged in alcoholic patients, whereas basal as well as stimulated GH levels were increased in cirrhotic alcoholics. It is concluded that alcohol per se influences T3 levels, but not the part of the hypothalamic-pituitary axis studied, and that the binding proteins are mostly determined by the degree of liver disease.

Sexual function and pituitary axis in insulin treated diabetic men

The prevalence of sexual dysfunction and the pituitary-gonadal function were studied in 72 consecutive diabetic male patients. Sexual dysfunction was found in 43% and in these patients peripheral neuropathy was significantly more frequent than in patients with normal sexual function. Sexual dysfunction was more frequent in patients at the age of 50--55 years than in young diabetics (age 25--30 years). No significant correlation between sexual dysfunction and the duration of the disease and no difference in the serum concentrations of luteinizing hormone, follicle stimulating hormone, prolactin, testosterone and oestradiol-17beta between patients with normal and reduced sexual function was found. It is concluded, that sexual dysfunction is not accompanied by altered serum concentrations of testosterone, oestradiol 17beta, gonadotrophins or prolactin. Sexual dysfunction correlates with peripheral neuropathy, but the high prevalence of dysfunction in males with short duration of diabetes without neuropathy makes other causes likely.

Recovery from Cucurbit leaf crumple virus (family Geminiviridae, genus Begomovirus) infection is an adaptive antiviral response associated with changes in viral small RNAs

A strong recovery response occurs in cantaloupe (Cucumis melo) and watermelon (Citrullus lanatus) infected with the bipartite begomovirus Cucurbit leaf crumple virus (CuLCrV). This response is characterized by initially severe symptoms, which gradually become attenuated (almost symptomless). An inverse relationship was detected between viral DNA levels and recovery, indicating that recovered tissues had reduced viral titers. Recovered tissues also were resistant to reinfection with CuLCrV; i.e., recovered leaves reinoculated with the virus did not develop symptoms or have an increased level of viral DNA. In contrast, infection of CuLCrV-recovered leaves with the RNA virus, Cucumber mosaic virus (CMV), disrupted recovery, resulting in the development of severe disease symptoms (more severe than those induced by CMV or CuLCrV alone) and increased CuLCrV DNA levels. Small RNAs with homology to CuLCrV DNA were detected in recovered and nonrecovered tissues; as well as in phloem exudates from infected, but not uninfected plants. Levels of these small RNAs were positively correlated with viral titer; thus, recovered tissues had lower levels than symptomatic tissues. In addition, viral DNA from a host that undergoes strong recovery (watermelon) was more highly methylated compared with that from a host that undergoes limited recovery (zucchini). Furthermore, inoculation of CuLCrV-infected zucchini with a construct expressing an inverted repeat of the CuLCrV common region enhanced recovery and reduced viral symptoms and viral DNA levels in newly emerged leaves. Taken together, these results suggest that recovery from CuLCrV infection is an adaptive antiviral defense mechanism, most likely mediated by gene silencing.

Biology and Molecular Characterization of Cucurbit leaf crumple virus, an Emergent Cucurbit-Infecting Begomovirus in the Imperial Valley of California

Cucurbit leaf crumple virus (CuLCrV) is an emergent and potentially economically important bipartite begomovirus first identified in volunteer watermelon plants in the Imperial Valley of southern California in 1998. Field surveys indicated that CuLCrV has become established in the Imperial Valley; and field plot studies revealed that CuLCrV primarily infects cucurbits, including cantaloupe, squash, and watermelon. Full-length DNA-A and DNA-B clones of an Imperial Valley isolate of CuLCrV were obtained by polymerase chain reaction (PCR) with overlapping primers. These clones were infectious in various cucurbits and common bean (cv. Topcrop); symptoms included stunted growth and leaf crumple, curl, and chlorosis. CuLCrV was not sap-transmissible, and immunolocalization and DNA in situ hybridization studies revealed that it is phloem-limited. A CuLCrV agroinoculation system was generated, and host range studies revealed differential susceptibility in cucurbits, with squash, watermelon, cantaloupe, and honeydew melon being most to least susceptible, respectively. Germplasm screening studies identified a number of resistant cantaloupe and honeydew melon cultivars. The genome organization of this CuLCrV isolate (CuLCrV-CA) is similar to other bipartite begomoviruses, and phylogenetic analysis placed CuLCrV in the Squash leaf curl virus (SLCV) cluster of New World bipartite begomoviruses. A CuLCrV-specific PCR test was developed which allows for differentiation from other begomoviruses, including SLCV.

Polymorphisms in the low-density lipoprotein receptor-related protein 5 (LRP5) gene are associated with peak bone mass in non-sedentary men: results from the Odense androgen study

PURPOSE

To investigate the impact of the Ala1330Val (rs3736228, exon 18) and Val667Met (rs4988321, exon 9) polymorphisms of the low-density lipoprotein receptor-related protein 5 (LRP5) gene on peak bone mass in young men.

METHODS

The Odense Androgen Study (OAS) is a population-based study comprising 783 Caucasian men aged 20-30 years. Genotyping was performed using real-time polymerase chain reaction (PCR) or fluorescence polarization. Bone mineral density (BMD) measurements were performed using dual-energy X-ray absorptiometry.

RESULTS

The CC, CT, and TT genotypes in Ala1330Val were found in 75.6%, 21.8%, and 2.6% of the participants, respectively. Similarly, the GG, GA, and AA genotypes of Val667Met were found in 89.7%, 9.8%, and 0.5%, respectively. For the Ala1330Val polymorphism, no significant differences between the genotypes were found regarding BMD in the overall study population. However, when analysis was restricted to non-sedentary men (n = 589), a significant association between the number of T-alleles and BMD in the spine and whole body were found. Each copy of the T-allele changed the Z-score of the spine by (median and 95% confidence interval) -0.21 [95% CI: -0.40; -0.03] (p < 0.02). Analysis suggested an association between the AA genotype in the Val667Met polymorphism and increased body height and decreased BMD of the femoral neck; however, no significant gene-dose effect of the A-allele could be demonstrated in the whole population. When the analysis was restricted to non-sedentary subjects, however, each number of A-alleles was associated with a change in Z-score of -0.26 [95% CI: -0.51; -0.01] (p = 0.04). No further significant results emerged with haplotype analysis.

CONCLUSION

The Ala1330Val and Val667Met polymorphisms in the LRP5 gene are significantly associated with peak bone mass in physically active men.

Population-based reference values for bone mineral density in young men

Population-based reference values for peak bone mass density in Danish men. BMD of total hip (1.078 +/- 0,14 g/cm2) differed significantly from values from National Health and Nutrition Examination Survey III and of total lumbar spine ((1.073 +/- 0.125 g/cm2) differed significantly from Hologic values.

INTRODUCTION

Geographic, ethnic, and socio-economic factors are known to affect bone mineral density (BMD) and peak bone mass significantly. Reference values for male peak bone mass are scarce, and the diagnosis of male osteoporosis often relies on values provided by producers of dual-energy X-ray absorptiometry (DXA) equipment.

METHODS

The aim of the present study was 1) to establish population-based reference values for BMD in young men and 2) to study subgroups based on variables with suspected impact on bone metabolism. We included 783 young Caucasian men aged 20 to 30 years in the Odense Androgen Study (OAS).

RESULTS

Peak BMD was attained within the third decade. Obesity (BMI > 30 kg/m2) was associated with higher BMD. Abuse of anabolic steroids as well as chronic illness was associated with lower BMD. Our population-based reference values for BMD of the total hip (1.078 +/- 0.14 g/cm2) differed significantly from published values from National Health and Nutrition Examination Survey III for non-Hispanic white men, while BMD of total lumbar spine (1.073 +/- 0.125 g/cm2) differed significantly from Hologic reference values.

CONCLUSIONS

Locally derived reference values are important to avoid false positive or false negative findings during work-up in patients evaluated for osteoporosis.

Hypopituitarism and mortality in pituitary adenoma

BACKGROUND AND OBJECTIVE

Previous studies on hypopituitarism and mortality have concluded that insufficient pituitary function is associated with decreased survival. For several reasons the results are difficult to compare - particularly because definitions and treatment of hypopituitarism have varied and various underlying disorders have been included. The purpose was to assess the relationship between mortality and pituitary function.

PATIENTS AND DESIGN

One hundred and sixty consecutive patients (99 men and 61 women) with functionless, suprasellar pituitary adenoma. All were operated on transsphenoidally during the period 1985-1996. Additional radiotherapy was given to 29 patients. Mortality was calculated 12.4 years (median, range 8.1-19.9) after operation. Postoperative hormonal deficits were treated in most, though GH substitution was given only to a minority of patients.

RESULTS

Postoperatively 30% of the patients had normal pituitary function (normal adrenocortical, thyroid and gonadal function), 26% were panhypopituitary and 36% had partial pituitary insufficiency. Forty-one patients had died (34.7 expected) yielding a standard mortality ratio (SMR) of 1.18 (95% confidence limits (CI) 0.87-1.60). SMR was significantly increased in women (1.97, CI 1.20-3.21) but not in men (0.83, CI 0.55-1.26). SMR in patients with normal pituitary function, panhypopituitarism and partial insufficiency were not different from that in the general population. SMR in hypopituitary women was substantially higher than in men with pituitary insufficiency. Treatment with growth hormone in GH-deficient patients did not influence survival.

CONCLUSION

Pituitary surgery for nonfunctioning adenoma and subsequent pituitary insufficiency had no effect on mortality in men, but was associated with significantly increased mortality in women. Suboptimal hormonal substitution in women may play a role.

Frequent occurrence of pituitary apoplexy in patients with non-functioning pituitary adenoma

BACKGROUND AND OBJECTIVE

There is agreement in the literature that pituitary apoplexy is a rare disorder. As our experience differs from this view, we analysed the incidence in patients operated on for a nonfunctioning pituitary adenoma.

PATIENTS AND DESIGN

One hundred ninety-two consecutive patients with a suprasellar, clinically inactive adenoma operated on during the period 1985-1996 were retrospectively reviewed. A diagnosis of pituitary apoplexy was made from relevant neurological symptoms together with pertinent findings at operation.

RESULTS

Pituitary apoplexy occurred in 41 patients (21%), in 23 patients within 12 days prior to the operation. The male/female ratio was 1.9. Median follow-up time was 13.7 years (range 8.9-19.9). During this period, 12 patients had died, yielding a standard mortality ratio of 1.09 (95% CI 0.62-1.92), similar to that in the patients who had not sustained pituitary apoplexy. Postoperatively, 24% of the patients had normal pituitary function, 38% were panhypopituitary and partial pituitary insufficiency was present in 38%. Subnormal GH secretion was present in virtually all patients tested. Two patients died within 60 days of surgery and in two no or incomplete data were available, although they most likely were panhypopituitary.

CONCLUSION

Most of our findings add little to what is known about pituitary apoplexy. On one point, however, they are contrary to previously presented data. We found a much higher incidence of pituitary apoplexy despite rather rigorous criteria for the diagnosis. The outcome as regards survival and endocrine function was not different from that in patients with a nonfunctioning adenoma who did not suffer pituitary apoplexy.

Prevalence of overweight, obesity and physical inactivity in 20- to 29-year-old, Danish men. Relation to sociodemography, physical dysfunction and low socioeconomic status: the Odense Androgen Study

OBJECTIVE

To assess the prevalence of overweight, obesity and physical inactivity in 20- to 29-year-old men and to analyze whether sociodemography, physical dysfunction and low socioeconomic status are independent correlates of obesity and physical inactivity.

DESIGN

Population-based, cross-sectional study.

SUBJECTS

Seven hundred and eighty-three Caucasian, Danish men, aged 20-29 years recruited from 2042 respondents in a questionnaire survey of 3000 men, randomly drawn from the Danish Civil Registration System.

METHODS

Questionnaire, interview and physical examination.

RESULTS

The 783 included men and the 2042 questionnaire respondents matched the background population demographically. The 783 men matched the questionnaire respondents as regards BMI, physical activity, chronic disease, medication, smoking, sociodemography and socioeconomic status. The prevalence of overweight and obesity was 31.7 and 7.9%, respectively (World Health Organization criteria). Using waist circumference (WC) cutoffs of 94 and 102 cm, the prevalence was 16.2 and 10.6%, respectively; 24.4% were physically inactive. BMI and WC increased significantly from age 20 to 29 years. Physical activity decreased significantly with age and correlated inversely with WC, but not with BMI. Occupation, geography, partner status, fatherhood and tobacco exposure were independently related with obesity and physical inactivity. Obesity was also related to musculoskeletal complaints, whereas chronic diseases and low educational level were associated with physical inactivity. Age was not independently related with either outcome.

CONCLUSION

In affluent societies, sociodemographic changes may partly explain the age-related decrease in physical activity and the parallel increase in WC and BMI.

Significantly higher adrenocorticotropin-stimulated cortisol and 17-hydroxyprogesterone levels in 337 consecutive, premenopausal, caucasian, hirsute patients compared with healthy controls

OBJECTIVE

To investigate whether elevated ACTH-stimulated 17-hydroxyprogesterone (17OHP) levels are caused by CYP21 genetic defects or by a general adrenal hyperresponsiveness in hirsute patients.

METHODS

A total of 337 hirsute patients were evaluated by Ferriman-Gallwey score, serum testosterone, ACTH-stimulated 17OHP, and cortisol during the follicular phase. A cutoff value of 16 nmol/liter for maximum ACTH-stimulated 17OHP (M17OHP) responses was defined as the upper limit of the 95% confidence interval (CI) for the 97.5 percentile in 42 female controls. All patients were offered total screening of the CYP21 gene, and 252 healthy, premenopausal women with regular menses underwent genetic screening.

RESULTS

Patients were divided into idiopathic hirsutism (IH) (n = 180) and polycystic ovary syndrome (PCOS) (n = 157) groups. M17OHP levels were significantly higher in IH [geometric mean value (nmol/liter +/- 2 sd) 12.2 (4.6-32.3)] and PCOS [11.9 (5.3-27.2)] compared with controls [8.5 (5.1-14.2)] (P < 0.001). A similar percentage of IH and PCOS patients had elevated M17OHP (20.5 vs. 20.8%, not significant), and these also had significantly higher 30-min cortisol levels compared with controls (P < 0.05). The prevalence of CYP21 mutations in patients was 8.6% compared with 6.3% in controls (P = 0.38). Ten of 19 carriers had M17OHP levels below the cutoff limit.

CONCLUSION

The significantly higher ACTH-stimulated levels of cortisol and 17OHP in hirsute patients indicated adrenal hyperresponsiveness in IH and PCOS. CYP21-carrier status could not explain the observed high prevalence of abnormal ACTH-stimulated 17OHP levels in the hirsute population.

Morphometric X-ray absorptiometry: reference data for vertebral dimensions in a population-based sample of young Danish men

PURPOSE

To determine reference values for vertebral heights in healthy young Danish males using morphometric X-ray absorptiometry (MXA).

MATERIAL AND METHODS

A population-based study group of 487 males aged between 20 and 30 years (mean 25 years) from the county of Funen, Denmark, were recruited. Using a Hologic QDR 4500 (dual energy X-ray absorptiometry) DXA-scanner, MXA scans covering the vertebrae from T4 to L4 were acquired for each subject. Anterior (Ha), middle (Hm), and posterior (Hp) heights of the thoracic (T4-T12) and lumbar (L1-L4) vertebral bodies were measured. Moreover, wedge, mid-wedge, crush I, and crush II ratios were calculated.

RESULTS

No correlation between vertebral dimensions and crush indices on the one hand and age or weight on the other were found. Body height, however, correlated significantly with the cumulated vertebral heights. Reference data for vertebral dimensions, wedge, mid-wedge, crush I, and crush II are tabulated.

CONCLUSION

The anterior, middle, and posterior heights of the vertebral bodies of T4 to L4 can be measured reproducible with MXA. In young men, the cumulative vertebral heights correlated with body height but not with age. Moreover, the wedge and crush indices were unrelated of both age and height.

Dose-, IGF-I- and sex-dependent changes in lipid profile and body composition during GH replacement therapy in adult onset GH deficiency

OBJECTIVE

Patients with GH deficiency of adult onset (GHDA) exhibit dyslipidaemia and increased cardiovascular morbidity. GH replacement potently reduces body fat and serum lipids in GHDA. In recent years, lower GH doses have been introduced. The purpose of this analysis was to explore the response relationship between GH doses, lipids and body composition.

DESIGN

Two consecutive, randomized 12-month GH replacement studies covering placebo and three different doses of GH (0.5, 1.0 and 1.7 IU/m(2) per day). Low and intermediate doses were IGF-I titrated.

PATIENTS

Fifty-eight patients with severe GHDA, not previously treated with GH and stably substituted for other endocrine deficiencies, were included in the study.

METHODS

Serum lipoproteins, serum IGF-I and body composition analysis by dual energy X-ray absorptiometry (DXA) were used.

RESULTS

Fifty-seven percent of patients exhibited low density lipoprotein (LDL) cholesterol levels above 4.16 mmol/l, corresponding to the American Heart Association threshold of 160 mg/dl. GH treatment resulted in significant decreases in total and LDL cholesterol, with no significant change in high density lipoprotein cholesterol or triglycerides. The low dose induced no significant changes in lipid levels, whereas the medium dose reduced LDL cholesterol and the high dose decreased both LDL and total cholesterol. The effects depended significantly on the GH dose and the level of IGF-I obtained, but not on gender. GH replacement induced dose-dependent reductions in fat mass and sex-dependent increases in lean mass.

CONCLUSIONS

GH given for 1 year at a dosage between 0.5 and 1.7 IU/m(2) per day reduced fat mass in a dose-dependent manner, increased lean body mass and lowered total and LDL cholesterol in patients with severe GHDA. Low dose GH treatment with normal IGF-I levels induced smaller changes compared with high dose therapy, and may need a longer treatment time.

Oral administration of the growth hormone secretagogue NN703 in adult patients with growth hormone deficiency

OBJECTIVE

Little is known of the usefulness of GH secretagogues (GHSs) in GH-deficient (GHD) adults. The objective of this study was to determine the number of responders to treatment with NN703 in GHD adults.

DESIGN

A multicentre, randomized, double-blind, and placebo-controlled study.

PATIENTS

Ninety-seven GHD adults were included.

MEASUREMENTS

The GH response before and after 1 week of oral treatment with NN703 (n = 83) or placebo (n = 14) was determined. The first and last dose of NN703 was 3 mg/kg, whereas the dose of NN703 was 1.5 mg/kg/day during the 6 days between the first and last doses. Furthermore, all 97 patients received 1 micro g/kg GH-releasing hormone (GHRH) 3 weeks after the last dose of NN703.

RESULTS

Serum GH peak and area under curve (AUC) values after the first NN703 administration were greater than those after placebo administration (P < 0.05). However, after correction for the lower body mass index (BMI) in the NN703 group, this difference lost statistical significance. After 1 week of therapy, GH peak and AUC values were similar following the final doses of NN703 and placebo. Serum peak and AUC values of other anterior pituitary hormones were similar between the NN703 and placebo groups both after the first and last administration of study drug. Nine of the 83 patients (11%) responded with a serum peak GH concentration >or= 5 micro g/l after the first and/or last NN703 administration, whereas no patient responded after placebo administration. Serum IGF-I was unaffected by 1-week NN703 treatment, whereas serum IGFBP-3 was increased (P < 0.05 vs. placebo) also after correction for BMI. Mean serum peak GH concentration after GHRH administration was 2.1 micro g/l (+/-0.3, SEM), which was higher than that after the first NN703 administration (1.32 +/- 0.3, P < 0.05).

CONCLUSION

NN703 administration was generally well tolerated. Eleven per cent of the GHD adult patients responded with a peak GH response >or= 5 micro g/l after the first and/or last administration of oral NN703. Although a majority of GHD adults will not respond to NN703, the present results suggest that oral NN703 treatment could be useful in some adult patients with moderately severe GHD. These patients may be identified by a test dose of GHS.

Evaluation of the optimum dose of growth hormone (GH) for restoring bone mass in adult-onset GH deficiency: results from two 12-month randomized studies

OBJECTIVE

To establish the optimum GH dose for restoring bone mineral density (BMD) in adult-onset GH deficiency (GHDA).

DESIGN

Two separate randomized, controlled clinical trials.

PATIENTS

Fifty-eight adults aged 45.1 (20-64) years with severe GHDA were followed in two 12-month studies. In the first study, patients were randomized to placebo or GH 1.7 IU/m2/day and in the second study GH 0.5 IU/m2/day or 1.0 IU/m2/day.

MEASUREMENTS

BMD of the spine, hip, forearm and whole body was measured at 0 and 12 months. Alkaline phosphatase (AP) and collagen markers serum C-terminal propeptide of type I collagen (PICP), type I collagen telopeptide (ICTP) and N-terminal propeptide of type III collagen (PIIINP) were measured at baseline and every 3 months.

RESULTS

Biochemical markers of skeletal and soft tissue collagen increased significantly and remained elevated throughout the study period. BMD changes depended on site, dose and gender. In placebo-treated patients, spinal BMD declined by 2.5%. At the low and medium doses, BMD increased by 2.4 and 3.1%, respectively, while a nonsignificant 0.2% decrease was seen with high dose. Forearm BMD decreased by 4.9% (P < 0.05) with high-dose treatment but remained unchanged at lower doses. Males showed larger gains in BMD, but the dose-response relationship was similar in males and females.

CONCLUSION

A GH dose of 0.5-1.0 IU/m2/day (4-9 micro g/kg/day) stimulated bone remodelling and increased BMD over 12 months in patients with severe GHDA, irrespective of gender. A higher dose (1.7 IU/m2/day congruent with 15 micro g/kg/day) was associated with initial declines in forearm and whole-body BMD.

Effect of reduced barometric pressure on water availability related to microbial growth

Data obtained from Mariner IV indicate that the barometric pressure on Mars is considerably lower than previously estimated. Current estimates from Mariner IV indicate a range from 4 to 7 mb and by near infrared spectroscopy 33-56 mb. Inasmuch as the pressure has a marked influence on availability of water, this should affect the existence of Martian life. At the maximum temperatures recorded on Mars, namely 25 degrees C, a barometric pressure of 30 mb is required for the retention of free water. The lower pressure, 4 mb, would suggest that the moisture is present as a vapor above the freezing point and consequently it is not available for utilizing by living cells. The lower estimates of barometric pressure also inversely affect the carbon dioxide concentration in the Martian atmosphere. Our previous studies have demonstrated that spores of Bacillus cereus survive, germinate and grow in a simulated Martian environment (2.4% CO2, 98 mb) supplemented with moisture. The studies described in this paper were designed to determine the effect of low barometric pressures (10 to 98 mb Hg) and high concentrations of carbon dioxide (37 to 100%) in the simulated Martian environment on survival and growth of B cereus. The organism was inoculated into a felsite-limonite soil at 8% moisture level. The temperature cycles used were 8 hr at -65 degrees C and 16 hr at 25 degrees C, or 20 hr at -65 degrees C and 4 hr at 25 degrees C. The data suggest that the organism after achieving maximum growth in the simulated Martian environment (2.4% CO2, 98 mb) immediately enters into the growth phase upon reinoculation into fresh soil. These data reflect upon the possibility of contamination through air movements. Based upon currently available Martian environmental data, the probability of contamination of Mars by terrestrial micro-organisms will be discussed.

Indirect evidence for decreased hypothalamic somatostatinergic tone in anorexia nervosa

OBJECTIVE

In animals, somatostatin (SRIH) and growth hormone (GH)-releasing hormone (GHRH) increase feeding via a common neural mechanism. Furthermore, SRIH counteracts the suppressive action of corticotrophin-releasing hormone (CRH) on food intake. Hypothetically, SRIH could be involved in the central feeding mechanism in anorexia nervosa (AN). Peripheral administration of pyridostigmine (PD) minimizes the release of hypothalamic SRIH.

DESIGN

To study the influence of hypothalamic somatostatinergic inhibition on the exaggerated somatotroph responsiveness to GHRH in patients with severe AN, two GHRH stimulation tests were performed in random order following pretreatment with placebo or PD 2 mg/kg body weight in 13 patients and in 10 age-matched healthy controls. The test procedure was repeated in the patients after weight gain.

RESULTS

In controls, PD potentiated the GHRH-stimulated GH rise but this effect was absent in AN patients. The relative potentiating effect of PD was inversely correlated to cortisol excretion levels and positively correlated to leptin serum levels. After weight gain the relative PD effect increased twofold.

CONCLUSION

The pyridostigmine-GHRH responsive pattern points indirectly to greater SRIH withdrawal and greater GHRH release in anorexia nervosa. Moreover, hypothalamic SRIH activity seems to be inversely related to cortisol levels, indirectly supporting the hypothesis that SRIH and CRH neuronal activity are inversely related in anorexia nervosa. Leptin, which is believed to act on hypothalamic feeding mechanisms, seems to be positively related to SRIH activity. Finally, the present data demonstrate that the potentiating effect of pyridostigmine in anorexia nervosa is related to body mass index and increases upon weight gain, suggesting that the low somatostatinergic tone is not primary but is related to the weight loss.

Fetal antigen 1 in healthy adults and patients with pituitary disease: relation to physiological, pathological, and pharmacological GH levels

Immunohistochemical analysis of the distribution of human fetal antigen 1 (FA1) in adult human tissues has demonstrated a strong association between FA1 and (neuro)endocrine structures. In the anterior pituitary gland FA1 was colocalized with GH, and the present study was performed to evaluate a possible relationship between GH and FA1. FA1 and GH levels were measured during a 24-h period at 20-min intervals. In contrast to the known GH peaks during 24-h sampling, there was no detectable FA1 peak. The FA1 responses to placebo were not significantly different from the responses to the combination of pyridostigmine and GHRH. No significant difference was found between basal FA1 (nanograms per ml) levels [median (minimum-maximum)] in healthy adults [n = 40; 28.6 ng/ml (12.5-72.0)], acromegalic patients [n = 11; 31.0 ng/ml (21.6-56.3)], and patients with GH deficiency [n = 22; 32.1 ng/ml (13.4-108.7)]. FA1 levels were significantly reduced, in the six of seven acromegalic GH responders to octreotide, from [median (minimum-maximum)] 30.6 ng/ml (20.0-43.1) to 20.3 (13.9-30.2; P < 0.02). There was no significant change during placebo. FA1 levels were significantly increased compared with placebo values during 3 months of GH therapy. The increase in FA1 levels was significantly higher than the change during placebo (P < 0.003). In conclusion, a common secretory and stimulatory pathway for FA1 and GH in healthy adults has been ruled out. However, we found that pharmacologically induced changes in GH levels during weeks to months had a corresponding direct or indirect effect on FA1 levels in patients with GH deficiency or acromegaly. However, a direct effect of octreotide on FA1 levels, independent of GH levels, has not been ruled out.

Update on endocrine disturbances in anorexia nervosa

The marked endocrine changes that occur in anorexia nervosa have aroused a great deal of interest, and over the last decade much research has been conducted in this field. The endocrine disturbances are not specific to this disorder, as they also occur in starvation states secondary to other causes, and they return to normal upon weight restoration. However, emaciation may have profound effects on psychological processes, establishing an intricate circular interaction whereby somatic and psychological manifestations of starvation may continue to act. The purpose of this paper is to provide an overview of the large body of literature concerning endocrine aspects of anorexia nervosa with the main focus on the latest results, which provide leads for potential etiological theories.

Determination of free insulin-like growth factor-I in human serum: comparison of ultrafiltration and direct immunoradiometric assay

Two fundamentally different methods are currently used for the determination of free insulin-like growth factor-I (IGF-I): ultrafiltration by centrifugation (UF) and direct immunoradiometric assay (IRMA). The aim was to evaluate a commercial IRMA (DSL, Webster, TX, USA) and to compare it with UF. In the IRMA it is recommended that samples be incubated for 2 h at 5;C. When comparing samples (n = 8) incubated for 1 and 2 h, levels increased by 27 +/- 5% (P< 0.0001). When incubating samples at 22;C instead of 5;C, levels increased by 192 +/- 32% (P< 0.0001). Addition of IGF-binding protein-1 (IGFBP-1) to normal sera (n = 6) dose-dependently decreased ultrafiltered free IGF-I only (P< 0.0007). Similarly, UF was more sensitive than IRMA to addition of IGFBP-2 (P< 0.05). In healthy subjects (n = 35) IRMA yielded 20% higher levels than UF (1.09 +/- 0.09 vs 0.91 +/- 0.12 microg/L; P< 0.0001). IRMA and UF yielded similar results in healthy subjects treated with IGF-I (n = 5) or growth hormone (n = 7) and in acromegalic patients (n = 6) before and after somatostatin analogue treatment. However, marked differences were observed in conditions with elevated IGFBP-1 and -2. In type-1 diabetics (n = 23) ultrafiltered free IGF-I was more reduced than IRMA free IGF-I (38 +/- 9 vs 76 +/- 7% of matched controls (n = 13); P< 0.0001). In patients with chronic renal failure (n = 25), IRMA free IGF-I was identical to control levels (n = 13), whereas ultrafiltered free IGF-I was decreased by 51 +/- 7% (P< 0.0001). Similarly, women with anorexia nervosa (n = 9) studied before and after weight gain showed significant changes in ultrafiltered free IGF-I only (P< 0.03). In conclusion, IRMA was not very robust with respect to variations in sample incubation and this may bias results. IRMA generally yielded higher levels than UF, in accordance with the knowledge that IRMA measures free plus readily dissociable IGF-I. IRMA was less affected than UF by added IGFBP-1 and -2, and reductions in free IGF-I were better revealed by UF than IRMA.