[Effect of bradykinin on pressure changes in the femur head epiphysis--an experimental and magnetic resonance tomography study].

Aim Of The Study: The aim of this study was to evaluate the response of the femoral head to intraosseous pressure increases and to document blood flow of periarticular soft tissue after infusion of vasoactive substances. Beside that the value and imagery of native MRI after induced intraosseous pressure increase should be estimated for early detection of femoral head necrosis.

Methods: The alteration of intraosseous pressure and peripheral blood flow of the femoral head of beagle dogs was examined after administration of bradykinin as a vasoactive substance followed by subsequent magnetic resonance imaging (MRI).

Effects of rigid contact lens prism ballasting on oxygen access to the cornea under static and dynamic conditions.

The effects of rigid contact lens material [polymethyl methyacrylate (PMMA) and itabisfluorofocon A] and prism ballasting (0, 1.5, 2.25, and 3 delta) on tear pump efficiency were studied by measuring corneal oxygen uptake rates on the right eyes of six human subjects under three conditions: (1) normal open eye; (2) after 5 min of static (without blinking) wear of the contact lens; and (3) after 5 min of dynamic (with blinking once every 5 s) wear of the same lens.

Neuroendocrine-immune interactions in the neonate.

Cytokine responses to lipopolysaccharides in neuroendocrine tissues are age- and tissue-dependent in neonatal pigs. Developmental differences in serum and tissue-specific responses are not necessarily equivalent. Lower levels of cytokine gene expression in neuroendocrine tissues of early neonates potentially could influence neuroendocrine and immune responses to infection.

[A comparison of the monitor and alternator findings of digital thoracic images with the aid of a computer-supported procedure].

Purpose: To compare softcopy and hardcopy reading of chest radiographs a software tool was designed for creating lesions with clearly defined size, location and contrast.

Method: An ROC study was performed using a set of chest radiographs with 300 simulated small nodules and linear details displayed on film and on a 1 K monitor. Six observers participated in the study.

Formation of reactive oxygen species by pentaerithrityltetranitrate and glyceryl trinitrate in vitro and development of nitrate tolerance.

Anti-ischemic therapy with organic nitrates is complicated by tolerance. Induction of tolerance is incompletely understood and likely multifactorial. Recently, increased production of reactive oxygen species (ROS) has been investigated, but it has not been clear if this is a direct consequence of the organic nitrate on the vessel or an in vivo adaptation to the drugs.

Dietary supplement with vitamin C prevents nitrate tolerance.

Enhanced formation of superoxide radicals has been proposed to play a major role in the development of nitrate tolerance in humans. We tested the effects of vitamin C (Vit-C) supplementation on glyceroltrinitrate (GTN)-induced hemodynamic effects during 3-d nonintermittent transdermal administration of GTN (0.4 mg/h) in nine healthy subjects.

Hemarthrosis as a major complication after arthroscopic subcutaneous lateral retinacular release: a prospective study.

The use of arthroscopic lateral release and medial imbrication of the vastus medialis obliquus for recurrent dislocation of the patella was evaluated prospectively in 31 patients. Patients were examined clinically as well as radiologically; the average length of follow-up was 34.4 months.

Two lyophilized polymer matrix recombinant human bone morphogenetic protein-2 carriers in rabbit calvarial defects.

We have developed a lyophilized bone morphogenetic protein (BMP) delivery device that can be formulated to control release over 2 to 8 weeks. Bioerodible poly (d,l lactide-co-glycolide) particles loaded with 90 micrograms recombinant human BMP-2 were suspended in either carboxymethylcellulose (CMC) or methylcellulose (MC) implants. Plain CMC and MC implants served as controls, as did a nonimplanted group.

The value of magnetic resonance imaging as postoperative control after arthroscopic treatment of osteochondritis dissecans.

The purpose of our study was to evaluate the value of MRI for preoperative arthroscopical planning in patients with osteochondritis dissecans. Based on the experience from 136 patients with osteochondritis dissecans of the knee or the ankle who were arthroscopically operated by retrograde drilling a follow-up study was carried out with 86 of them by clinical, radiological and postoperative magnetic resonance imaging (MRI) examinations. The evaluation was made by means of a visual analogue scale and a score system.

Quantification of superoxide radicals and peroxynitrite in vascular cells using oxidation of sterically hindered hydroxylamines and electron spin resonance.

The reactions of two hydroxylamines, 1-hydroxy-3-carboxy-pyrrolidine (CP-H) and 1-hydroxy-2,2,6,6-tetramethyl-4-oxo-piperidine (TEMPONE-H), with superoxide radicals and peroxynitrite were studied. In these reactions corresponding stable nitroxyl radicals 3-carboxy-proxyl (CP) and 1-hydroxy-2,2,6,6-tetramethyl-4-oxopiperidinoxyl (TEMPONE) are formed and the amount of them can be quantified by electron spin resonance (ESR). It was found that CP-H and TEMPONE-H provide almost the same efficacy in assaying peroxynitrite by ESR in vitro at pH 7.

Unexpected, tolerance-devoid vasomotor and platelet actions of pentaerythrityl tetranitrate.

Efficacy of nitrate therapy is limited by tolerance. A surprising upregulation of ex vivo platelet activity, a decrease in platelet thiol levels, and an enhanced release of vasoconstrictors from platelets is associated with enhanced superoxide-mediated oxidant stress leading to vascular tolerance to nitrates. We tested the NO-donor pentaerythrityl tetranitrate (PETN), which to date had not been precisely tested either with regard to the induction of tolerance or to a potential development of changes in platelet activity in comparison with glycerol trinitrate (GTN).

Avascular osteonecrosis of the acetabulum.

Objective: To investigate the possible occurrence of osteonecrosis in the acetabulum in patients with non-traumatic necrosis of the femoral head.

Design And Patients: One hundred and seventy-nine patients with non-traumatic femoral head necrosis were assessed by MRI and radiography for the presence of acetabular necrosis. Three criteria were established to differentiate between osteonecrosis and osteoarthritic changes: (1) heterogeneous morphology and irregular contours of the lesion; (2) typical demarcation lines of osteonecrosis; (3) deficient accumulation of intravenous gadolinium in the affected regions.

Corneal responses to lens transmissibility.

Background: Lens transmissibility (Dk/L) and corneal relief from hypoxia are not linearly related. We describe graphically and by equations the relationship between corneal relief (scaled in oxygen shortfall units) and Dk/L across the transmissibility range of 1.2 to 189 x 10(-9) (cm/sec)(ml O2/ml mmHg).

Chondroblastoma of the foot.

A total of 322 cases of chondroblastoma were referred to the Armed Forces Institute of Pathology between 1960 and 1990. Ten additional cases of chondroblastoma were treated at Walter Reed Army Medical Center between 1985 and 1993. Forty-two of these involved the foot, two of which were treated at Walter Reed Army Medical Center.

Evidence that tyrosine phosphorylation regulates N-cadherin turnover during retinal development.

N-cadherin, a member of the cadherin family of calcium-dependent cell adhesion molecules, mediates adhesive and signaling interactions between cells during development. N-Cadherin undergoes dynamic spatiotemporal changes in expression which correlate with morphogenetic movements of cells during organogenesis and histogenesis. We have previously shown that N-cadherin expression during development is regulated by several mechanisms, including mRNA expression, cytokine modulation, and proteolytically mediated turnover, yielding the NCAD90 protein.

Early detection of avascular necrosis of the femoral head following renal transplantation.

This prospective study included 43 patients undergoing renal transplantations. Magnetic resonance imaging (MRI) and X-rays of the hip joints were produced 3 and 12 months after transplantation. In 6 hip joints of 4 patients (9.

Recurrent dislocation of the patella and the Goldthwait operation.

In this study 17 patients with recurrent dislocation of the patella were followed up 10 years after their Goldthwait operation. The subjective and clinical findings were excellent or good in 70%. X-radiographs indicated osteoarthritis of the femoropatellar joint in 60%.

[Segmental hypermobility of the spine before and following discectomy].

In 145 patients with open dissectomies (virgin back) preoperative functional x-rays (flexion/extension) were available. 80 patients out of this group could be used for additional postoperative functional x-rays. The mean follow-up was 28 +/- 18 months.

[Proton spin tomographic changes of the femoral shaft in patients with kidney transplantation].

In a prospective study 43 patients were reviewed 3 and 12 months after renal transplantation. The patients had MRI examinations and plain x-rays of the hips as well as punch biopsies of the iliac crest. In 9 patients diffuse, inhomogeneous bilateral changes of the MRI-signal patterns of the femoral diaphysis were seen.

[The epiphyseal plate in hemodialysis, peritoneal dialysis and following kidney transplantation].

We evaluated growth, maturity of the skeleton and formation of skeletal deformities and epiphysiolysis of the femoral head in 22 children with end-stage renal failure undergoing haemodialysis, CAPD (continuous ambulatory peritoneal dialysis) and after kidney transplantation. We found growth retardation and disturbances of skeletal maturity in 64% of the children and skeletal deformities in 45%. Children undergoing haemodialysis showed a higher rate of retardation in growth and skeletal maturity than those undergoing CAPD and kidney transplantation.

Influence of joint stability on the results of arthroscopic subacromial decompression.

We performed arthroscopic subacromial decompression on 70 patients. Each of them had either type I or type II impingement according to Neer. Sixty-five patients were then observed for a postoperative period of three years.

[Critical assessment of indications for arthroscopic lateral release and medial tightening of the knee joint].

Unlabelled: Based on the results of a retrospective study of 50 patients with mild lateral tracking and lateral compression of the patella (32 patients) and recurrent patellofemoral dislocation (18 patients), we present the technique, the results, the complications and the indications for the endoscopic lateral retinacular release and medial drawing tight of the capsule. The average age of the patients was 28.8 years (range: 10-53).

Holmium: YAG laser-induced aseptic bone necroses of the femoral condyle.

In laser-controlled cartilage-ablation arthroplasties, the attention focuses more and more on the depth effects of the various lasers, especially as heat necroses of the cartilage and even in places of the bone were found in animal experiments. For the first time, two cases of holmium: YAG laser-induced aseptic bone necrosis of the femoral condyles after cartilage ablation are described.