Determination of the modulus of elasticity of bone material by an acoustical approach at the forearm distinguishes women with and without vertebral fractures independent of bone mineral density

The modulus of elasticity is a parameter characterizing fracture stability of bone independent of bone mineral density. Measurement of acoustical properties of the forearm by determination of the resonant frequency of the ulna in longitudinal direction as a function of sound transmission velocity after adjustment of the measuring result by ulna length yields information about the modulus of elasticity. It was the aim of this study to investigate whether this parameter may distinguish between subjects with and without vertebral fractures independent of bone mineral density. Fifty females (61.1 +/- 9.1 years) were enrolled into the study, 25 with, and 25 age-matched without prevalent osteopor…

Endothelial Function and Arterial Stiffness in Uncomplicated Type 1 Diabetes and Healthy Controls and the Impact of Insulin on These Parameters during an Euglycemic Clamp

BACKGROUND In addition to its role in glucose metabolism, insulin has shown to exert numerous vascular effects, and an impaired vascular function of insulin is assumed to be a major contributor in the development of vascular complications. Arterial augmentation (AP) and the augmentation index (Aix) are surrogate parameters of arterial stiffness and are commonly used as predictors for cardiovascular risk. The aim of this study is to investigate the effect of insulin on arterial stiffness and parameters of endothelial function in patients with type 1 diabetes and healthy control subjects. METHODS Fourteen patients with type 1 diabetes (six male, eight female) with a mean age of 36.6 +/- 11.8 …

Prädiktive genetische Untersuchungen: Individualisierung von Diagnostik und Therapie bei Familien mit multipler endokriner Neoplasie Typ II

BACKGROUND AND OBJECTIVE When multiple endocrine neoplasia type 2 (MEN2) is suspected, genetic tests are at the centre of screening procedures. It was the aim of this study to compare the diagnostic value of molecular biological investigations with that of conventional biochemical tests. PATIENTS AND METHODS The study cohort consisted of all 144 patients cared for in our department since 1990 with the suspected diagnosis of MEN2 (evidence of a medullary thyroid carcinoma [MTC]), coexistence of two MEN2 tumours or a family history of MEN2. 14 of the 144 patients (from 12 families) were already known to have an hereditary MTC, while the remaining 130 had been referred for further diagnostic i…

Age-dependence of bone material quality shown by the measurement of frequency of resonance in the ulna

In women before and after the age of peak bone mass, identical values of bone mineral density (BMD) can be obtained. However, there is a much higher incidence of osteoporotic fractures in older women. We investigated whether a deterioration of bone material quality with increasing age might contribute to this phenomenon. Material properties of bone tissue can be characterized by the modulus of elasticity, which is correlated to the square of sound transmission velocity. In this study, sound transmission velocity was determined in cortical bone by measuring the frequency of resonance in the ulna in the direction of the bone's longitudinal axis and correcting the values by multiplying by ulna…

Suppressed Levels of Serum Cortisol Following High-Dose Oral Dexamethasone Administration Differ between Healthy Postmenopausal Females and Patients with Established Primary Vertebral Osteoporosis

Hypercortisolism and glucocorticoid treatment, even in a low dose or administered topically, may influence bone metabolism. It was the aim of this study to investigate whether there might be differences in the regulation of endogenous cortisol secretion between patients with established primary vertebral osteoporosis and healthy controls. Suppressed morning serum cortisol concentrations in a 3 mg dexamethasone overnight suppression test were compared in well-defined healthy postmenopausal women (n = 149) and osteoporotic patients classified as having established primary vertebral osteoporosis with no clinical features of hypercortisolism (n = 78). Suppressed cortisol in the healthy controls…

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

Summary 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 µg/kg GH-releasing hormone (GHRH) 3 weeks afte…

Architecture in cortical bone and ultrasound transmission velocity

The square of ultrasound transmission velocity in a material is correlated to the modulus of elasticity, which is an indicator of its mechanical properties. This might make the measurement of ultrasound transmission velocity useful in the noninvasive diagnosis of bone diseases. Bone, however, is not an isotropic material but is architecturally structured. The aim of our study was to investigate and especially to quantify the influence of architecture in cortical bone on ultrasound transmission velocity. Twenty-two rectangular, flat specimens of cortical bone were prepared from diaphysis of fresh pig radius. Ultrasound transmission velocity was measured parallel and perpendicular to directio…

Evaluation of ultrasound transmission velocity and 3-dimensional radiology in different bone types for dental implantology: a comparative ex vivo study.

Objective To evaluate ultrasound transmission velocity (UTV) for assessment of mechanical bone quality, an ex vivo comparison of different bone types measured with UTV, 2-dimensional (2D) histomorphometry and with 3-dimensional (3D) radiology (cone-beam computerized tomography [CBCT], computerized microtomography [μCT]) was conducted. Study Design Clinical cortical, cancellous, and mixed bone (each n = 6) was measured via UTV (m/s), CBCT (white pixel/black pixel ratio [WP/BP]), μCT (bone volume/total volume [μBV/TV]), and histomorphometry (bone volume/total volume [hBV/TV]). UTV values were correlated with 2D-histomorphometry and 3D-radiologic results. Results For the cortical, cancellous, …

Hypothyreose, Hyperthyreose und Therapie mit Schilddrüsenhormonen: Einflüsse auf das Skelettsystem

Impact of environmental temperature on skin thickness and microvascular blood flow in subjects with and without diabetes.

Glucose measurement from different skin areas might be influenced by changes in skin texture due to several environmental confounders. Our study was performed to investigate the effect of changes in ambient temperature on skin thickness and microvascular skin blood flow in subjects with and without diabetes at the lower forearm.Thirteen subjects with diabetes and seven without diabetes participated in the study. The investigations were performed in a temperature- and humidity-controlled climatic chamber (EMPA, St. Gallen, Switzerland). Starting at 25 degrees C, the environmental temperature was changed in 4 degrees C steps every 40 min. Skin thickness was measured by an ultrasonic reflectio…

Intraportal transplantation of allogenic pancreatic islets encapsulated in barium alginate beads in diabetic rats.

The survival of microencapsulated islets transplanted into the unmodified peritoneal cavity is limited, even if capsular overgrowth is restricted to a minimum, due to an insufficient oxygen supply to the islets. Therefore, research efforts should focus on finding or creating a transplantation site, which permits a closer contact between the encapsulated islets and the blood. For this reason, the liver could be an interesting candidate. The aim of the present study was to test the hypothesis that the intraportal transplantation of allogenic islets encapsulated in small-sized barium alginate beads is safe and succeeds to induce normoglycemia in diabetic rats. The intraportal transplantation o…

Influence of glucose control and improvement of insulin resistance on microvascular blood flow and endothelial function in patients with diabetes mellitus type 2.

The study was performed to investigate the effect of improving metabolic control with pioglitazone in comparison to glimepiride on microvascular function in patients with diabetes mellitus type 2.A total of 179 patients were recruited and randomly assigned to one treatment group. Metabolic control (HbA1c), insulin resistance (HOMA index), and microvascular function (laser Doppler fluxmetry) were observed at baseline and after 3 and 6 months.HbA1c improved in both treatment arms (pioglitazone: 7.52 +/- 0.85% to 6.71 +/- 0.89%, p.0001; glimepiride: 7.44 +/- 0.89% to 6.83 +/- 0.85%, p.0001). Insulin-resistance decreased significantly in the pioglitazone group (6.15 +/- 4.05 to 3.85 +/- 1.92, p…

Vitamin D und Osteoporose: Pathogenese - Therapie

Speed of sound measurements in mandibular and phalangeal bone during growth

The micromechanical and elastic properties of bone, its structural maturity and, indirectly, mineral density are important factors for the planning and assessment of orthodontic and/or jaw orthopaedic treatment. This clinical study was undertaken to evaluate age-related changes in the anterior mandibular body. The speed of sound (SOS) has demonstrated age dependency in various peripheral bones and has been proposed as an alternative method for investigating bone parameters without the use of radiation. The ultrasound transmission velocity was measured in 184 healthy subjects (93 females, 91 males; mean age 17.6 +/- 13.7 years). According to the statistical analysis, the data did not reveal …

Relation between bone quality values from ultrasound transmission velocity and implant stability parameters--an ex vivo study.

Aim The objective of this study was to determine the relationship between bone qualities measured by ultrasound transmission velocity (UTV) and primary implant stability parameters measured by radiofrequency analysis (RFA) and push-out test (POT) in an ex-vivo model. Materials and methods Three blocks of fresh porcine bone samples were obtained from different anatomic regions, correlating to cortical, mixed and cancellous bone. Mechanical bone qualities of these samples were measured using UTV (expressed in m/s) prior to implantation. Three similar implants (4.1 × 11 mm, AstraTech OS) were inserted into each of the procured bone blocks. The evaluation of implant-bone interface stability was…

Validation of a mechanical method for measuring skin thickness: relation to age, body mass index, skin thickness determined by ultrasound, and bone mineral density.

In a number of endocrine disorders, typical changes in skin thickness can be observed which make measurement of skin thickness interesting in this field. A newly developed mechanical method for measuring skin thickness is presented. Using a digital measuring screw on the dorsum of the hand with a defined measuring force of 10 newton and a resulting tissue compression of 1500 mm Hg, highly reproducible results were obtained (mean coefficient of variation 2.56%). In 129 women, 37 to 78 years old, body mass index < 30 kg/m2, there was no significant relation between body mass index and skin fold thickness. A negative correlation between skin fold thickness and age (r = 0.37, p < 0.001) was det…

Vergleich des Hypoglykämieempfindens und der hormonellen Gegenregulation während einer kontrollierten Hypoglykämie: Ein Beitrag zur Diagnostik des Hypoglykämie-Unawareness-Syndroms bei Typ-1-Diabetikern

BACKGROUND AND OBJECTIVE Diabetics with abnormal hypoglycaemia awareness cannot recognize hypoglycaemic symptoms early and adequately enough to respond, thus endangering in everyday life not only themselves but also others. Thus it is important to diagnose such symptoms early and assess the extent to which the diabetic is at risk of severe hypoglycaemia. This study was designed to contribute to the evaluation of hypoglycaemia awareness in type 1 (IDDM) diabetics. PATIENTS AND METHODS In 57 diabetics (IDDM) awareness of typical hypoglycaemic warning symptoms and of hormonal counterregulation were tested during controlled induced hypoglycaemia. A questionnaire was used to measure at fixed tim…

Radiosynthesis of 1-(4-(2-[18F]fluoroethoxy)benzenesulfonyl)-3-butyl urea: a potentialβ-cell imaging agent

Summary Tolbutamide (1) is a sulfonurea agent used to stimulate insulin secretion in type 2 diabetic patients. Its analogue 1-(4-(2-[ 18 F]fluoroethoxy)benzenesulfonyl)-3butyl urea (3) was synthesized in overall radiochemical yields of 45% as a potential b-cell imaging agent. Compound 3 was synthesized by 18 F-fluoroalkylation of the corresponding hydroxy precursor (2 )w ith 2-[ 18 F]fluoroethyltosylate in DMF at 1208C for 10 min followed by purification with HPLC in a synthesis time of 50 min. Insulin secretion experiments of the authentic 19 F-standard compound on rat islets showed that the compound has a similar stimulating effect on insulin secretion as that of tolbutamide (1). The part…

Interdisziplinäre Diagnostik und Therapie des ischämisch-osteomyelitischen diabetischen Fußsyndroms

Fortgeschrittene Stadien des diabetischen Fussyndroms (DFS) mit ischamischer und osteomyelitischer Komponente fuhren im Rahmen gangiger Versorgungsstrukturen regelhaft zur Minoramputation, gefolgt von ischamisch bedingter Wundheilungsstorung und Extremitatenverlust. Selbst in spezialisierten Behandlungseinrichtungen stellen periphere arterielle Verschlusskrankheit (pAVK) und Osteomyelitis die groste Herausforderung im Bemuhen um den Extremitatenerhalt dar. Wahrend die Behandlung von polyneuropathischen Fuslasionen in den Handen von Diabetologen zur erfolgreichen Domane der konservativen Medizin geworden ist, ist fur die Therapie von fortgeschrittenen, ischamisch und osteomyelitisch komplizi…

Establishment of a quantitative RT-pCR for detection of vascular cell adhesion molecule-1 transcripts in endothelial cells after stimulation with advanced glycation endproducts.

Advanced glycation endproducts (AGE) are supposed to increase endothelial expression of adhesion molecules like vascular cell adhesion molecule-1 (VCAM-1) by inducing an intracellular stress with subsequent activation of nuclear transcription factor NF-kappa-B. Quantitative analysis of VCAM-1-transcription has not been demonstrated concerning this topic. Thus, the aim of this study was to establish quantitative reverse transcription polymerase chain reaction (RT-PCR) assays using a spacer gene in order to measure the amounts of specific mRNA for VCAM-1 in human umbilical vein endothelial cells (HUVEC) which were stimulated with AGE-albumin (AGE-BSA). A recombinant RNA-standard was synthesiz…

Endosonography of the adrenal glands: normal size — pathological findings

Transabdominal sonography of the adrenal glands frequently is non-successful. It was the aim of this project to improve the imaging of the adrenal glands using high resolution sonography in order to obtain information about even small changes in these organs. Therefore, endosonographic imaging was investigated using an endosonoscope PENTAX FG32UA. The correct identification of the adrenal glands was examined in five human cadavers. A total of 58 patients with 113 adrenal glands (in 3 cases history of unilateral adrenalectomy) were investigated. 109 adrenal glands (97%) were identified and evaluated. Healthy adrenal glands are slightly hyperechoich and regarding their echogeneity comparable …

Bone Mineral Density and Bone Metabolism in Diabetes Mellitus

The effect of diabetes mellitus on bone metabolism and bone mineral density is discussed controversially. Diabetes mellitus due to an autoimmune process seems to be associated with low turnover osteopenia either in the animal model or in children and adolescents. A number of factors are discussed as being involved, but in this age group clinical symptoms are missing. Adult patients of either sex with IDDM show a reduced bone mineral density when measured at peripheral sites such as the distal forearm or the femoral neck, diabetic complications such as neuropathy and microangiopathy seem to pronounce the deficit of bone mass. In these patients, osteopenia is accompanied by a high turnover si…

Malignant and Unclear Histological Findings in Incidentalomas

&lt;i&gt;Background:&lt;/i&gt; The management of incidentalomas with tumor size 3 cm and larger is still under controversial discussion. &lt;i&gt;Study Design:&lt;/i&gt; Clinical charts of 65 patients who underwent adrenalectomy for an incidentaloma were reviewed. &lt;i&gt;Results:&lt;/i&gt; Sixty-five patients were operated. There were 28 men and 37 women with a median age of 56.9 years. Median size of all resected lesions was 4.1 cm. Indications for surgery were tumor size equal and larger than 3 cm, recurrent pain, hormone status and patients’ fear of malignancy. In 45 patients, the adenomas did not meet the defined criteria of malignancy. There were 9 cases of adrenal hyperplasia, and t…

Growth hormone substitution in growth hormone-deficient adults: Effects on collagen type I synthesis and skin thickness

Growth hormone stimulates collagen type I synthesis. Collagen type I is a common matrix compound in a large number of connective tissues. The aim of our study was to prove whether a stimulation of collagen type I synthesis might be accompanied by a deposition of collagen type I in the skin (cutis). Twenty growth hormone-deficient hypopituitary patients were included in a randomised, double-blind, placebo controlled, prospective, twelve-month study (eighteen patients assessable at the end of the study). The patients were treated with recombinant human growth hormone 0.25 U/kg/week subdivided in daily subcutaneous injections beginning with half the dosage during the first four weeks. During t…

Increased Arterial Augmentation and Augmentation Index as Surrogate Parameters for Arteriosclerosis in Subjects with Diabetes Mellitus and Nondiabetic Subjects with Cardiovascular Disease

Background: Arterial augmentation (AP) and the augmentation index (Aix) are surrogate parameters of arterial stiffness and are commonly used as predictors for cardiovascular risk. The aim of this study is to compare these parameters in diabetic subjects and nondiabetic cardiovascular risk subjects with healthy control subjects. Methods: One hundred sixty-six nonsmoking subjects aged between 35 and 70 years were included in the study, which included 100 subjects with cardiovascular disease but not diabetes (mean age 62.73±8.75 years), 33 subjects with type 2 diabetes (66.58±2.69 years), and 33 healthy controls (51.89±8.91 years). In these subjects, arterial stiffness was measured by the diff…

Using ultrasound transmission velocity to analyse the mechanical properties of teeth after in vitro, in situ, and in vivo irradiation.

Ultrasound transmission velocity (UTV) in isotropic material as a measure for the modulus of elasticity was correlated to mechanical properties. Changes in micromechanical properties of radiated teeth and influence of the oral cavity were to be evaluated nondestructively. UTV was measured in extracted teeth after 36 Gy and 62 Gy of in situ (enorally, with no contact to the oral cavity) and in vitro irradiation. Relative to controls, teeth subjected to 62 Gy in vivo showed higher UTV values for dentine and enamel. Sound teeth irradiated with 60 Gy in situ also showed higher UTV values for enamel, whereas dentine values were not significantly different from those of control. The mechanical pr…

SPET/CT image co-registration in the abdomen with a simple and cost-effective tool

Fusion of morphology and function has been shown to improve diagnostic accuracy in many clinical circumstances. Taking this into account, a number of instruments combining computed tomography (CT) with positron emission tomography (PET) or single-photon emission tomography (SPET) are appearing on the market. The aim of this study was to evaluate a simple and cost-effective approach to generate fusion images of similar quality. For the evaluation of the proposed approach, patients with neuroendocrine abdominal tumours with liver metastases were chosen, since the exact superimposition in the abdomen is more difficult than in other regions. Five hours following the injection of 110 MBq (111)In…

Abnormal pentagastrin response in a patient with pseudohypoparathyroidism

The case of a 25 year old female patient with pseudohypoparathyroidism type I (PHP) and hypercalcitoninaemia is reported. She was referred to our clinic because of recurrent hypocalcaemia associated with paraesthesias and muscle cramps. She had no signs of Albright hereditary osteodystrophy (AHO), a normal mental status and no family history of hypocalcaemia or any other endocrine disease. Considering the laboratory results with hypocalcaemia, hyperphosphataemia, normal vitamin D and normal creatinine with an extraordinary elevated PTH we diagnosed pseudohypoparathyroidism type I. She had delayed pubertal development with menarche in the age of 20 and hypothyroidism with an atrophic thyroid…

99mTc–MAG3–Nierenfunktionsszintigraphie ohne und mit Captopril zur Diagnostik der renovaskulären Hypertonie

In this study, the diagnostic value of renal function scintigraphy performed both without and with ACE inhibition has been evaluated using the new radiopharmaceutical 99mTc-MAG3. In cases of decompensated renal artery stenoses, the typical scan finding with this tubular excreted agent was shown to be a distinct parenchymal nuclide retention in combination with a delayed appearance of the radiotracer in the pelvic system. Using this criterion in 43 patients with suspected renovascular hypertension, sensitivity and specificity were 89 and 88%, respectively. Bilateral positive findings were non-specific; excluding them from the study, specificity increased to 100%. In renal insufficiency, capt…

Gender-, age- and time-dependent dosing of growth hormone in adults - real-world data from a decade of clinical practice in Germany.

We evaluated treatment patterns and gender-dependent dosing of growth hormone (GH) substitution in adults with GH deficiency (AGHD). Data on GH dose were collected (2003-2013) from 509 GH-treated patients (mean age: 48.9 years; 47% female) enroled in the observational German NordiWin study (NCT01543880). The impact of gender, age, treatment duration and calendar year on GH treatment patterns was evaluated by multiple regression analysis. Mean (SD) baseline GH dose (mg/day) was similar between females (0.25 [0.19] and males (0.24 [0.15]), but increased with treatment duration (at year 10, 0.55 [0.48] and 0.31 [0.09] in females and males, respectively), reflecting patient dose titration. GH d…

Effect of long-term treatment with GH on bone metabolism, bone mineral density and bone elasticity in GH-deficient adults

OBJECTIVE Adults with GH deficiency (GHD) commonly have subnormal bone mineral density (BMD), and have been reported to have an increased risk of fractures. It has been suggested that GH replacement therapy may have beneficial effects on bone in such patients. The aim of this study was to investigate the effects of long-term GH replacement therapy on bone metabolism, BMD and bone elasticity in adults with GHD. DESIGN At the start of the study, 20 adults with GHD were randomized to receive either GH, 0.25 IU/kg/week (the ‘GH group’) or placebo (the ‘placebo group’). After 6 months, patients in the placebo group were switched to GH therapy, and all patients received GH for a further 42 months…

In-vivo investigation of material quality of bone tissue by measuring apparent phalangeal ultrasound transmission velocity

The square of ultrasound transmission velocity in a material is related to the modulus of elasticity, which is known to be an indicator of stability in bone. The aim of our study was to use ultrasound transmission velocity to obtain information about the material properties of bone tissue, keeping other factors possibly influencing ultrasound transmission as constant as possible. Apparent phalangeal ultrasound transmission velocity (APU) measured in 54 isolated, fresh pig phalanges was shown to be independent of bone mineral density (BMD) measured by SPA. Fastest sound transmission led exclusively through cortical bone so that intertrabecular connectivity in spongious bone could not influen…

Color-coded duplex endoscopic ultrasound of the adrenals.

Imaging of the adrenals by endoscopic ultrasound (EUS) is a valuable technique for detection and localization of adrenal lesions, but endosonomorphological tumor distinction remains difficult. In this single-center study, the amount of blood flow in common adrenal lesions, such as adrenal adenomas, adrenal hyperplasia, and pheochromocytomas, was visualized by color-coded duplex EUS (CD-EUS) and was retrospectively analysed. Therefore, we reviewed our EUS database to evaluate and correlate the perfusion patterns of common adrenal lesions with histologically confirmed diagnosis, possible malignancy, and endosonomorphological features such as echogeneity, echostructure, and tumor size. CD-EUS …

Gender-, age- and time-dependent dosing of growth hormone in adults – real-world data from a decade of clinical practice in Germany

We evaluated treatment patterns and gender-dependent dosing of growth hormone (GH) substitution in adults with GH deficiency (AGHD). Data on GH dose were collected (2003–2013) from 509 GH-treated patients (mean age: 48.9 years; 47% female) enroled in the observational German NordiWin study (NCT01543880). The impact of gender, age, treatment duration and calendar year on GH treatment patterns was evaluated by multiple regression analysis. Mean (SD) baseline GH dose (mg/day) was similar between females (0.25 [0.19] and males (0.24 [0.15]), but increased with treatment duration (at year 10, 0.55 [0.48] and 0.31 [0.09] in females and males, respectively), reflecting patient dose titration. GH d…