Myocardial surface PO2--an indicator of myocardial tissue oxygenation?

The validity of myocardial surface tissue PO2 (PtO2) as a reliable indicator of transmural myocardial tissue oxygenation was studied in six anaesthetised, open chest pigs. Epicardial surface PtO2 was correlated with other variables of myocardial tissue oxygenation such as regional blood flow, coronary venous PO2, O2 saturation, PCO2 and regional myocardial lactate extraction. The study design was based on an experimental model in which the effects of a pacing induced tachycardia on tissue oxygenation of ischaemic and normally supplied myocardium were measured. Two platinum multiwire surface electrodes were placed on the epicardium, on the areas supplied by the left anterior descending coronary artery (LAD) and the left circumflex coronary artery (CX). The LAD was constricted to reduce mean surface PtO2 in the LAD area to about 50% of its baseline value. This did not affect surface PtO2 in the CX area. The reduction of surface PtO2 in the LAD area was associated with decreases in coronary venous PO2 and O2 saturation and with increases in coronary venous lactate and PCO2. Subendocardial regional blood flow and the subendocardial to subepicardial flow ratio were significantly lower than in the CX area. Increasing the heart rate by pacing (+45 beats.min-1) led to an increased degree of ischaemia as shown by fall in surface PtO2 in the LAD area to values around zero kPa, by marked increase in coronary venous lactate and PCO2, by reduction in total (-10%) and subendocardial (-40%) LAD flow and by deterioration of the subendocardial to subepicardial flow ratio. The increased degree of ischaemia was not accompanied by an increase in O2 extraction. The marked decrease in surface PtO2 occurred in spite of a slight increase in the subepicardial regional blood flow (+10%); thus the increase in O2 delivery was not sufficient to meet the increase in O2 demand. Total flow was increased by 27% in the CX area without changes in the subendocardial to subepicardial flow ratio and in the surface PtO2 values. When pacing was stopped, surface values of PtO2 in the LAD area returned to prepacing values, as did lactate extraction and coronary venous PCO2. Clear and close relationships with surface PtO2 were found for regional lactate extraction, coronary venous PCO2 and the normalised subendocardial RBF. Poor or no correlations were found for the normalised subepicardial regional blood flow, the coronary venous O2 saturation and the absolute values of subendocardial and subepicardial regional blood flow.(ABSTRACT TRUNCATED AT 400 WORDS)

High turnover bone disease following lung transplantation.

Recipients of lung transplants are at very high risk for significant bone loss. Nevertheless, data on bone disease after lung transplantation are still limited. We, therefore, retrospectively evaluated the data of 33 patients surviving at least 1 year after lung transplantation (LTx) who were seen in our outpatient clinic for osteologic evaluation. Results of clinical evaluations, radiographs, and dual-energy X-ray absorptiometry (DXA) were related to each other, to clinical variables, and to serum levels of osteocalcin, parathyroid hormone (PTH), and 25-hydroxyvitamin D: 14 of 33 patients (42%) had vertebral fractures, 9 of whom were diagnosed within 2 years after transplantation. Bone mineral density values (DXA) were markedly decreased and predictive of compression fractures. 25-Hydroxyvitamin D levels were low in 13 patients (39%) and PTH was elevated in 7 (21%). Despite corticosteroids and low 25-hydroxyvitamin D, serum osteocalcin was elevated in 12 patients (36%). This was only partially explained by hyperparathyroidism, low sex hormones, and impaired renal function, and may partly be caused by cyclosporin A. We thus conclude that severe symptomatic bone disease is common in lung transplant recipients and due to a complex situation including high turnover bone loss and hypovitaminosis D. DXA can be used to estimate fracture risk for individual patients.

Inhibition of Fc epsilon RI-mediated activation of mast cells by 2,3,4-trihydropyrimidino[2,1-a]isoquinolines.

Assays based on reporter gene technology represent today an important tool in the pharmaceutical industry for discovering novel compound classes interfering with the activation and signaling of target cells after stimulation. Here we describe a reporter gene assay targeting mast cell activation of IgE plus antigen, established in an attempt to identify substances preventing type I allergy (allergic rhinitis, allergic conjunctivitis, allergic asthma, and acute and chronic urticaria). The assay is based on a murine mast cell line designated CPII, stimulation by IgE plus antigen, and a reporter gene construct with the TNF alpha promoter linked to luciferase as a read-out system. Via screening about 50,000 substances, compound 2 was found to inhibit the reporter gene induction in the submicromolar range in this assay. Analogues of compound 2 of the 2,3,4-trihydropyrimidino[2,1-a]isoquinoline type were synthesized starting from 2-alkyl-substituted benzonitriles via aminolysis with 1,3-diaminopropane, dimetalation of 2-substituted 2-phenyl-1,4,5,6-tetrahydropyrimidines with n- and sec-butylithium, reaction with carboxylic acid methyl esters, and finally acidic dehydration. From about 50 derivatives, compound 41 was selected as a lead structure with an IC50 of 0.2 microM and a TC50 of 2.7 microM. In a first profiling in secondary assays, it effectively interfered with the production of mediators such as TNF alpha, IL-4, IL-6, IL-13, and leukotriene synthesis as measured by the corresponding ELISAs. In addition, a passive cutaneous anaphylaxis in mice (a typical type I reaction) is inhibited to more than 90% by compound 41, when administered intradermally 90 min before challenge.

A comparison of quantitative computed tomography and dual X-ray absorptiometry for evaluation of bone mineral density in patients on chronic hemodialysis.

Chronic renal failure leads to a reduction of bone mineral density (BMD). Therefore, noninvasive methods to evaluate BMD are also used regularly in this patient population. In this study, we compared the results of two widely used methods, quantitative computed tomography (QCT) of the lumbar spine and dual x-ray absorptiometry (DXA) at different sites in 90 patients on chronic hemodialysis. Additionally, we also determined various clinical and biochemical data to assess their relationship to BMD at the different measurement sites. A total of 75% of our patients was found to have reduced BMD, and 25% had an average z-score below -2. Z-scores obtained by the different methods and at the different measurement sites within an individual patient varied considerably from completely normal to severely reduced values. Multivariate analyses using clinical and biochemical parameters showed lower values of BMD at all measurement sites after transplantation and marginally higher values after parathyroidectomy, which was seen only in DXA measurement at the femoral neck. We conclude from our study that determination of BMD in chronic hemodialysis patients yields highly variable results, depending on the technique used. As long as the exact clinical relevance of these results has not been determined, regular routine measurement of isolated sites of BMD cannot be advocated in this patient population.

Effect of bone cylinder length on distraction osteogenesis in the rabbit tibia.

The viability and osteogenic potential of bone cylinders for bone transport was investigated in one tibia of 18 mature male New Zealand rabbits. The length of the bone cylinder was equal to or twice that of the diameter of the tibia. The cylinder was cut subperiosteally with an externally cooled oscillating saw from a lateral approach, after a specific unilateral external fixator had been applied. To simulate bone transport, one end of the cylinder was fixed to the distal bone stump by a cerclage wire and healing and revascularization was prevented by an interposed expanded polytetrafluoroethylene membrane. The periosteum was re-adapted and sutured, and distraction began 10 days postoperatively at 0.25 mm/12 hours for 22 days. New bone formation in the distraction gap was quantified by dual energy x-ray absorptiometry and by computer-assisted histomorphometry of polyfluorochrome-labeled undecalcified bone sections and corresponding microradiographs. In half of the animals with each size cylinder, osseous bridging occurred, so the findings on distraction osteogenesis are reported only for the remaining nine animals. Generally, centripetal mineralization of the gap with two distinct zones of ripening bone structures and a central radiolucent fibrocartilaginous zone could be distinguished. Neither absorptiometry nor histomorphometry showed significant differences in the overall amount of this new bone formation for the bone cylinders of two different lengths. However, osteogenesis was significantly greater at the proximal end than at the cylinder. New bone was formed predominantly from endosteal sites in the smaller cylinders and from periosteal sites in the larger cylinders. Histologically, there was complete necrosis of both sizes of cylinders, followed by revitalization through newly formed vascular channels.(ABSTRACT TRUNCATED AT 250 WORDS)

Recorticalization after bifocal internal bone transport in the double-plated sheep femur.

Distraction osteogenesis and bone remodelling after the end of bone transport were investigated in one femur each of six adult male sheep. A newly designed internal distraction device was used. A custom-made osteosynthesis plate was fixed on the lateral side of the femur, and two transporting plates driven by a transcutaneously inserted screwdriver moved two bone cylinders simultaneously over a 40 mm defect. An additional plate was applied ventrally to stabilize the device. Bone transport was begun 2 weeks postoperatively at 1 mm/day at each transporting plate until they came into contact. New bone formation within the distraction gaps was evaluated by computed tomography scans and was quantified at 4 and 6 months by dual energy x-ray absorptiometry as well as histomorphometry on polyfluorochrome-labelled undecalcified ground sections and microradiographs. At 4 months, all distraction gaps were bridged by abundant newly formed bone trabeculae, which were reduced and condensed to cortex-like layers of new bone at 6 months. Less new bone was always found under the lateral device than in the unplated medical and dorsal segments, but the amount of new bone under the ventral plate was comparable with that in the unplated regions. The results of this pilot study show that distraction osteogenesis can be achieved with an internal device such as this one and that recorticalization and restoration of a medullary canal occur despite the relatively rigid internal stabilization by the plates.

Imaging of tendons--adaptation, degeneration, rupture.

Tendon imaging is mainly performed with ultrasonography (US) and magnetic resonance imaging (MRI) and has been improved within the last years because of technical advancements and a better understanding of tendon pathology. Several concepts concerning the etiology and the course of tendon diseases have influenced image interpretation and vice versa. Adaptive mechanisms within the tendon tissue against stress can be observed mainly on histologic specimens and not macroscopically or with in-vivo imaging. Degeneration may occur in the form of tendinitis, peritendinitis, enthesitis, or myotendinal junction abnormality. Distinct imaging findings exist for most of these forms. Many concepts that have been developed to explain tendon degeneration have been applied on virtually all tendons in the human body. They can be grouped into those which focus on hypovascularization, on biomechanical overload, and on degeneration secondary to other underlying disease. Tendon rupture seems, in many cases, to be the final stage of tendinitis. From this point of view, imaging may be used to predict the risk of tendon rupture together with other intrinsic and with extrinsic parameters. These considerations result in the concept of the "vulnerable zone" and of the "critical phase" in which tendon ruptures may predominantly occur.

Diagnostic imaging of the occipito-cervical junction in patients with rheumatoid arthritis. Plain films, computed tomography, magnetic resonance imaging.

Fifty-five patients with confirmed chronic polyarthritis were admitted to this prospective study. The occipito-cervical region was visualized by plain radiography, computed tomography (CT) and magnetic resonance (MR) imaging. These modalities and the results are compared. In the presence of chronic polyarthritis, radiography of the occipito-cervical region visualized only bone lesions, while CT provided a good picture of both bone lesions and soft-tissue alterations. CT is an effective modality for the diagnosis of chronic polyarthritis in the occipito-cervical region. MR imaging was less sensitive in depicting bone lesions. In comparison with CT, however, MR images produced more frequent and more impressive visualization of soft-tissue alterations. MR imaging is most suitable for visualizing complications of the spinal cord.

Asymptomatic cholangitis with the acquired immuno-deficiency syndrome. Clinical and diagnostic features.

A case of hepatobiliary involvement in a 36-year-old man with the acquired immunodeficiency syndrome is presented.

Sonography of the tongue and floor of mouth. Part II: Neoplasms of the tongue.

Frequently, correct evaluation of space-occupying lesions in the tongue is not possible with clinical methods only. In an attempt to assess the value of sonography in the detection of tongue lesions, we used submental sonography to examine 62 patients with suspicious palpatory findings upon physical examination of the tongue. Ultrasound detected 45 out of 47 tumours that were eventually confirmed either by surgery or by biopsy. Inadequate technique was the only factor that affected the detection rate. Sonography appears to be a reasonable guide in determining size and site of a tumour of the tongue. Thus, more precision in therapy planning may be achieved.

[Radiological aspects of emphysema (author's transl)]. / Röntgenologische Aspekte beim Emphysem.

Radiology is the basic factor in diagnosis of emphysema. Further differentiation is possible by assessment of the concomitant cardio-vascular changes. By these means, the type of emphysema (accompanying emphysema in chronic bronchitis, or primary emphysema) can be established.

[Radiologic-endoscopic correlation in ulcerative colitis]. / Radiologisch-endoskopische Korrelation bei Colitis ulcerosa.

Double-contrast irrigoscopies (DCI) performed in 32 patients with confirmed ulcerative colitis are reviewed and correlated with colonoscopy. Whereas endoscopy proved more efficient in assessing superficial changes of the mucosa, DCI was found to be superior in the detection of deeper mucosal lesions and changes in the anatomic aspect of the colon wall. Moreover, DCI showed advantages in the evaluation of the entire colon including the coecum; examination of the coecum by endoscopy was achieved in 31% only of the scrutinised cases.

[Fine relief of the stomach and diagnosis of gastritis. A radiologic-endoscopic-histologic comparative study]. / Magenfeinrelief und Diagnose der Gastritis. Eine radiologisch-endoskopisch-histologische Vergleichsstudie.

To assess the sensitivity of radiology in diagnosis of gastritis within 2 hours endoscopy and biopsy of the stomach and double contrast barium meal were performed. The diagnosis was established of the morphologic picture of the areae gastricae, which were sufficient visible in 33 out of 50 cases (66%). In 7 patients radiologic findings were normal, 13 patients showed superficial gastritis, 10 patients had superficial gastritis with signs of atrophy and in 3 patients there was an erosive gastritis. In all 33 patients (100%) there was a complete correlation of radiologic and endoscopic findings, in 24 out of 33 cases (73%) even correlation between radiologic and histologic classification. These results are discussed and confrontated with literatures.

[Baker cysts: an accompaniment of chronic diseases of the knee joint (author's transl)]. / Baker-Zyste: Begleitsymptom chronischer Erkrankungen des Kneigelenkes.

One hundred and twenty one Baker cysts demonstrated by arthrography have been analysed. Morphologically one must distinguish between distension cysts and dissection cysts. Distension cysts are more common with various diseases of the knee joint (68% of all cysts). Dissection cysts (32%) are found particularly with inflammatory-rheumatic diseases and are rarely of degenerative or post-traumatic origin. Acute rupture of the cyst was observed on ten occasions. Repeated rupture, which had only been suspected previously, was demonstrated by arthrography in four patients. It is pointed out that Baker cysts may imitate the features of acute thrombophlebitis.

[Comparison of the renal ultrasound-furosemide test with the isotope nephrogram. Possible clue to the retention phenomenon?]. / Vergleich des renalen Ultraschall-Furosemidtests mit dem Isotopennephrogramm. Möglicher Hinweis auf das Phänomen der Retention?

In 23 patients with essential hypertension renographic and sonographic examination of the kidneys was compared. No correlation could be observed for functional parameters and urinary excretion between the two different methods. Correlations have only been detected between renographic retentions and furosemide-conditioned swelling of the kidneys in sonography: patients with severe retention showed a statistically significant stronger response to furosemide. The increased retention in the renal pelvis could be responsible for alterations in sonographic findings. This study provides new data on the mechanisms of retention, whereby retention in the renal pelvis in some patients seems to be most probably caused by nephrosclerosis.

[Magnetic resonance tomography of the craniocervical junction in chronic polyarthritis]. / Magnetresonanztomographie des kranio-zervikalen Uberganges bei chronischer Polyarthritis.

Magnetic resonance imaging and conventional radiographs and tomograms were correlated in 61 patients with chronic polyarthritis. Radiographs of the occipito-cervical junction only demonstrated bone lesions, erosions were detected on conventional tomograms. MRI was adequate for demonstration of bone abnormalities and soft tissue lesion and was especially suitable for detection of complications at the cervical spinal cord.

[Renal osteodystrophy: the spectrum of the x-ray symptoms in modern forms of kidney transplantation and long-term dialysis therapy]. / Renale Osteodystrophie: Spektrum der Röntgensymptomatik bei modernen Formen der Nierentransplantation und Dauerdialysetherapie.

Plain film radiography and microradioscopy represent standard imaging for diagnosis and grading of renal osteodystrophy. The aim of this retrospective study was to evaluate the effects of modern therapeutic regimens on skeletal abnormalities as diagnosed radiographically. 198 patients were investigated. X-ray findings of 38 patients from 1981-1983 (16-66 years, 40.1 +/- 13.4; 23 male, 15 female) were compared with those of 160 patients from 1991 (20-71 years, 48.4 +/- 12.5; 98 male, 62 female). We found significant differences in respect of the spectrum and the degree of skeletal abnormalities. The prevalence of phalangeal resorptions lowered from 87 to 50%, the prevalence of soft tissue calcification from 68 to 57%. Therefore, renal osteodystrophy is not as extensive as it was ten years ago, but it still continues to be an unavoidable complication of renal insufficiency.

[Sonography of the Achilles tendon and its bursa]. / Die Sonographie der Achillessehne und ihres Gleitlagers.

Pain and disturbed function in the sole of the foot leads to damage of the tendo Achilles and to abnormalities in its vicinity. They are frequent consequences of some sporting activities (jogging). Differentiation between bursitis, fat necrosis, degenerative changes in tendons and their rupture and from abnormalities of the ankle joint is important for treatment. In the symptomatic patients whom we examined, the bursa was involved in 72.9% and lesions of the tendo Achilles were found in 62.1%.

[Realtime sonography in the diagnosis and follow-up of malignant tongue tumors. II. Detection and staging]. / Real-time-Sonographie in Diagnostik und Verlaufskontrolle maligner Zungentumoren.Teil II: Nachweis und Staging.

92 sonographic examinations performed in 62 patients were evaluated to determine the possible application of sonography in the diagnosis and follow-up of malignant tumours of the tongue. Squamous cell carcinomas were by far dominant and proved to be hypoechoic, mainly inhomogeneous and ill-defined masses. In most cases, they ranged between 2 and 4 cm. in diameter. In 50% of the lesions an infiltration of the pharynx wall was confirmed, and exulcerations were correctly detected by sonography in 75%. In preoperative determination of the size of the tumour, sonography correctly detected the size in 93% of the cases and was thus markedly superior to the clinical palpatory examination, which determined a mere 43% correctly. Sonography should be included in the pretherapeutic staging of tumours of the tongue to objectify the clinical findings. It is also adequate to document tumour behaviour during radiation.

[Aseptic humerus head necrosis--tortuous path of a maker of scythes through expert medicine]. / Probleme der aseptischen Humeruskopfnekrose--Irrwege eines Sensenschmiedes in der Begutachtungsmedizin.

The case report is presented of a 50 year-old scythe smith who produced 1400 scythes daily in piece-work over a period of 17 years. He complained for the first time in 1977 about severe pain in his left shoulder. Six years after the onset of pain aseptic necrosis of the humeral head was finally diagnosed by reviewing old X-rays of 1977, but the patient had meanwhile absolved a troublesome journey through a variety of incorrect-medical diagnostic and therapeutic procedures. The patient's history, previous reports and the actual clinical findings observed in our department are presented in this paper. We consider that this patient is suffering from an occupational disease which should be legally recognised as such.