A dynamical measure of the black hole mass in a quasar 11 billion years ago.

Tight relationships exist in the local Universe between the central stellar properties of galaxies and the mass of their supermassive black hole (SMBH). These suggest that galaxies and black holes co-evolve, with the main regulation mechanism being energetic feedback from accretion onto the black hole during its quasar phase. A crucial question is how the relationship between black holes and galaxies evolves with time; a key epoch to examine this relationship is at the peaks of star formation and black hole growth 8-12 billion years ago (redshifts 1-3).

In-situ characterization of the bacterial biofilm associated with Xeroform™ and Kaltostat™ dressings and evaluation of their effectiveness on thin skin engraftment donor sites in burn patients.

Biofilm forms when bacteria surrounded by an extracellular matrix aggregate on a surface. It can develop on many surfaces, including wound dressings; this can be particularly nefarious for burn patients undergoing skin grafting (autograft) for burn wound coverage as they often suffer from compromised immune system function. Autograft donor sites are particularly vulnerable to biofilm formation; as such, timely healing of these sites is essential.

Is the femoral head dead or alive before surgery of slipped capital femoral epiphysis? Interest of perfusion Magnetic Resonance Imaging.

Background: The most common complication of slipped capital femoral epiphysis (SCFE) is avascular necrosis (AVN) of the femoral head. Surgical treatments including reduction of the femoral head are considered as a risk factor for avascular necrosis. The purpose of this study was to investigate the role of perfusion Magnetic Resonance Imaging (MRI) into the surgical decision-making sequence.

Gastrointestinal calcium absorption and dietary calcium load: relationships with bone remodelling in vertebral osteoporosis.

Patients with vertebral osteoporosis have a wide range of bone loss rates, bone remodelling rates and capacities for gastrointestinal (GI) calcium absorption. To test the hypothesis that variations in GI absorptive capacity determine rates of bone loss or remodelling, we have sought relationships between calcium absorption or vitamin D metabolite levels on the one hand and rates of cancellous and cortical bone loss (measured by serial quantitative computed tomography in the radius; n = 25) or indices of bone remodelling in tetracycline-prelabelled transiliac biopsies (n = 41) on the other, in a sequential untreated group. Calcium absorption (net and true) was measured in 18-day balances and by a two-isotope deconvolution method (fractional absorption and maximum absorption rate, MAR).

Temporal variations in iliac trabecular bone formation in vertebral osteoporosis.

The histologic heterogeneity of osteoporosis relative to normal controls has attracted great interest. There has been controversy as to whether patients with high turnover osteoporosis may convert to a normal or low turnover form, and vice versa. We have studied 44 patients over 12 years by dynamic histomorphometry and 85Sr kinetics+calcium balance performed within 60 days in 20 patients (Group 1) and 75-808 days apart in the remainder (Group 2).

[A case of severe rarefaction osteopathy associated with tabes dorsalis].

The authors report the case of a 63 years old man who presented 13 years after a diagnosis of a tabes dorsalis, stress fractures of the lower limbs and Charcot's joints (knees). 7 years later, he had multiple stress fractures of the sacrum and pelvis and of the ribs following a minor trauma. Laboratory investigations revealed a major osteoporosis probably related to the neurochirurgical complications of the tabes dorsalis.

[Bone involvement in primary oxalosis. Study of 20 cases].

The authors report 20 cases of primary oxalosis with bone involvement, late revealed in adults in 19 cases. They have studied the clinical, radiological and histological manifestations of this bone oxalosis. 19 cases had an end stage chronic renal failure, either treated by maintenance hemodialysis, or by renal (or liver-renal) graft.

Iliac trabecular bone formation predicts radial trabecular bone density changes in type 1 osteoporosis.

In 28 patients with idiopathic or postmenopausal type 1 (spinal crush fracture) osteoporosis, resorption indices and dynamic measurements of trabecular bone formation based on in vivo tetracycline labeling in 7.5 mm transiliac biopsies have been compared with trends in radial cortical and trabecular bone density measured with computed tomography. Positive correlations were observed between trabecular bone density trends in the radius and indices of bone formation in the ilium.

hPTH 1-34 treatment of osteoporosis with added hormone replacement therapy: biochemical, kinetic and histological responses.

Twelve patients with vertebral fracture osteoporosis were recruited into a trial of treatment with hPTH 1-34 by daily injection for 1 year combined (from the 5th month) with an anti-resorptive agent (oestrogen, n = 9; nandrolone, n = 3). Treatment outcomes were monitored by biochemical and radiotracer measurements together with histomorphometry of transiliac biopsies before and at the end of treatment following double in vivo pre-labelling with demethylchlortetracycline. Indices of whole body bone formation, obtained from the analysis of 85Sr data, showed substantial increases (P less than 0.

The relationship between serum vitamin D concentrations and in vivo tetracycline labeling of osteoid in crush fracture osteoporosis.

Twenty of 22 consecutive British patients with crush fracture osteoporosis had transiliac bone biopsies following double in vivo tetracycline labeling synchronized with the collection of serum for the measurement of vitamin D metabolites. A significant but direct (rather than inverse) relationship was found between 25-hydroxyvitamin D (calcidiol) levels and the fraction of cancellous surfaces covered with osteoid not taking either tetracycline label (r = 0.53, P less than 0.

Comparison between radial bone mineral density measured by single photon absorptiometry and histomorphometric bone mass parameters measured on iliac crest biopsies.

Bone mineral density (BMD) measured by single photon absorptiometry (SPA) with a Moolsgard 1100 device on the distal and proximal part of the radius was compared with histomorphometric parameters measured on iliac crest biopsies in 37 patients suffering from various bone disorders. In the whole population, a good correlation was observed between the cancellous bone volume (Cn-BV/TV) measured on iliac crest biopsies and BMD from both the proximal part of the radius (r = 0.76, p less than 0.

[Efficacy of x-ray computed tomography in the diagnosis of tumors of the mediastinum. 103 cases].

A prospective study was carried out in 103 patients with mediastinal tumors to determine diagnostic value of CT imaging. A precise diagnosis was obtained in 80% of cases, the detection sensitivity being 100%, 98% and 71% respectively for fatty tumors (20 cases), solid tumors (59 cases) and cystic tumors (24 cases). The weak sensitivity of detection of cystic tumors was due to the spontaneously elevated density of mediastinal cystic tumors and the fact that 2 patients in this series with cystic lesions presented enhanced images with contrast.

Skeletal blood flow, iliac histomorphometry, and strontium kinetics in osteoporosis: a relationship between blood flow and corrected apposition rate.

In 20 untreated patients with idiopathic or postmenopausal osteoporosis, kinetic studies of skeletal blood flow (using 18F) and bone turnover (using 85Sr) were combined with dynamic histomorphometry performed on transiliac biopsies taken within 6 weeks of each other. In 8 patients the combined studies were repeated after treatment. A further 5 patients were studied only while receiving treatment.

The assessment of bone formation and bone resorption in osteoporosis: a comparison between tetracycline-based iliac histomorphometry and whole body 85Sr kinetics.

Bone formation and resorption have been measured in patients with idiopathic osteoporosis by histomorphometry of 7.5-mm trephine biopsies and in the whole body by 85Sr radiotracer methodology and calcium balances. The studies were synchronized and most were preceded by double in vivo tetracycline labeling.

Periodic courses of human 1-34 parathyroid peptide alternating with calcitriol paradoxically reduce bone remodelling in spinal osteoporosis.

In an attempt to achieve an anabolic response in both axial and peripheral bone, we treated twelve patients with osteoporosis using human 1-34 parathyroid peptide given discontinuously. The peptide was given as seven daily subcutaneous injections followed by 21 days' treatment with 0.25 mg calcitriol orally.

Beneficial effects of aminohexane diphosphonate in patients with Paget's disease of bone resistant to sodium etidronate.

Clinical and biochemical resistance to sodium etidronate therapy is not rare in patients with severe Paget's disease of bone, especially after several courses of treatment. Sixteen patients with Paget's disease of bone and well-documented resistance to sodium etidronate were treated with a new diphosphonate, aminohexane diphosphonate, given orally for three months at a daily dose of 400 mg. These patients comprised a selected population of patients with very active disease, as shown by a mean 20-fold increase of serum alkaline phosphatase levels before aminohexane diphosphonate therapy.

Coherence treatment of postmenopausal osteoporosis with growth hormone and calcitonin.

Fourteen women with postmenopausal osteoporosis, all having at least one vertebral crush fracture, were randomly assigned to two treatment arms, each lasting 24 months. The coherence treatment group (7 patients) was treated in the following sequence: human growth hormone (hGH) 7 IU subcutaneously daily for 2 months, followed by 3 months of salmon calcitonin (CT), 100 MRC units every other day. After a 3 month rest period, this sequence was repeated twice.

Intravenous disodium etidronate therapy in Paget's disease of bone and hypercalcemia of malignancy. Effects on biochemical parameters and bone histomorphometry.

Nineteen patients with Paget's disease and four patients with hypercalcemia of malignancy underwent hypocalcemic therapy with etidronate disodium (etidronate) administered intravenously. The dosage for patients with Paget's disease was 4.3 mg/kg/day, infused on each of seven consecutive days.

Primary bone oxalosis: the roles of oxalate deposits and renal osteodystrophy.

Primary oxalosis is a rare congenital disorder. The excessive oxalate biosynthesis induces deposits in many organs, particularly in kidney and bone. The late onset of primary oxalosis is reported in a 50-year-old man.

Effects of clodronate on immobilization bone loss.

Clodronate can be used in animals to prevent the effects of immobilization on bone. For this reason we have studied the effects of this agent on immobilisation bone loss in man. We administered clodronate by mouth to 14 paraplegic patients (400 mg/d, n = 7; 1600 mg/day, n = 7), and compared its effect with a placebo (n = 7).

Fluoride treatment in corticosteroid induced osteoporosis.

Severe osteoporosis with multiple vertebral fractures occurred in two girls receiving prolonged high dose corticosteroids for relapsing dermatomyositis. Sodium fluoride, supplemented with calcium and vitamin D, helped control secondary osteoporosis in one case and should be considered as part of the curative treatment of corticoid induced osteoporosis.

Serum bone gamma carboxyglutamic acid-containing protein in primary hyperparathyroidism and in malignant hypercalcemia. Comparison with bone histomorphometry.

Serum bone gamma-carboxyglutamic acid-containing (Gla) protein (sBGP), a sensitive and specific marker of bone turnover, was measured in 25 patients with primary hyperparathyroidism and in 24 patients with bone metastases with or without hypercalcemia. Despite similar levels of hypercalcemia, sBGP was increased in primary hyperparathyroidism (14.2 +/- 9.

Heterogeneity of fracture syndromes in postmenopausal women.

Studies were performed on 32 women with vertebral crush fractures (mean age, 65.1 yr) and 27 patients with recent hip fractures (mean age, 83.6 yr).

[Myelomatous bone. Histomorphometric study and therapeutic effects].

In order to evaluate quantitatively the bony changes in multiple myeloma, 118 transiliac bone biopsies in non decalcified bone were made in patients with multiple myeloma and studied histologically. Areas of osteoclastic resorption were increased when compared to normal controls and the number of osteoclasts/mm2 in spongy bone was significantly more elevated in zones massively invaded by plasmocytes than in non-invaded zones. The binding of tetracycline to osteoid was increased, indicating active bone formation.

[Comparative study of serum osteocalcin and of the histomorphometric evaluation of iliac biopsy in postmenopausal osteoporosis].

The histological examination of iliac biopsies in patients with osteoporosis shows varying stages of remodeling which cannot be detected by the usual laboratory tests. We measured the serum osteocalcin level, a new test, specific for bone, in 26 postmenopausal women with primary osteoporosis. The results were correlated to the findings of the iliac biopsy.