[Hemodynamic effects and adverse effects of the anti-arrhythmic substance AWD-G256 in man]

In 19 patients with different supraventricular tachycardias the antiarrhythmic drug AWD-G256 was studied to investigate the effects on hemodynamic parameters. Over all, stroke volume, pulmonary pressure and systemic blood pressure were not significantly altered. The only main adverse effect was a transient rise of serum transaminases in two patients. We conclude that AWD-G256 is usually hemodynamically tolerated, but the antiarrhythmically effective dosage is not reached yet.

[Clinical-electrophysiologic studies on the actions of the anti-arrhythmic substance AWD-G256 in man]

The effects of the new antiarrhythmic drug AWD-G256 (1) were investigated by clinical electrophysiology (His bundle electrography, programmed electrical stimulation) in 19 patients with supraventricular tachycardias but without structural heart disease. In a maximal dosage of 0.45 mg/kg body mass 1 only minimally affects electrophysiological parameters of the impulse formation and conduction. At this time the therapeutic value of 1 is not clear.

[The pharmacokinetics of a new anti-arrhythmic substance, Z-2-amino-5-chlorobenzophenoneamidinohydrazone (AWD-G256)]

In 4 studies blood levels and metabolites of Z-2-amino-5-chlorobenzophenoneamidinohydrazoneacetate (AWD-G256) after different dosages and forms of application on patients and healthy volunteers were investigated. In addition the pharmacokinetic parameters were calculated. The determination of pharmacokinetic parameters was possible only after i.v. application of dosages higher than 0.30 mg.kg-1 b.m. as well as p.o. administration of dosages higher than 100 mg. The blood level curve after i.v. application demonstrated a 2-compartment model and after p.o. application a 1-compartment model. Exact pharmacokinetic data can't be clear estimated with this studies.

Drug use in pregnancy: east German data of an international collaborative study

In an epidemiological collaborative international study under the auspices of WHO-Euro the drug use in pregnancy was investigated in 22 countries in 14,778 women and in hospitals of three different levels. The East German state Thuringia took part according to the annual birth rate with 300 women in 3 hospitals (Jena, Gera, Greiz). In the international average, 14% of the enrolled women took no drugs during pregnancy before admission to hospital for delivery. In East Germany 44% of the women taking part in the study had no drug administration during pregnancy. The critical use of iron preparations and vitamins there has to be mentioned. Under delivery, 99% of the Thuringian women received drugs. In the puerperium the administration of ergot derivatives and of laxatives exceeds the international average and has to be critically revised, but the administration of antiinfectives in only 1/5 and of analgetics 1/3 of the international average.

Investigations into a new antiarrhythmic substance Z-2-amino-5-chlor-benzophenon-amidin-hydralazin in humans

Z-2-amino-5-chlor-benzophenon-amidin-hydralazin is a new chemical potential antiarrhythmic substance. The blood levels were investigated after different dosages and forms of administration in patients and volunteers. The determination of the substance can be performed by high-pressure liquid chromatography. In addition the pharmacokinetic parameters were calculated. The pharmacokinetic profile is similar in humans and animals.

Articular cartilage changes following meniscal lesions. Repair and meniscectomy studied in the rabbit knee

A well-defined, longitudinal lesion in the avascular part of the medial meniscus of the right knee was made in 30 rabbits. After 3 months, the lesion was repaired surgically in 12 rabbits, was untreated in 12 rabbits, and a meniscectomy was performed in 6 rabbits. The articular cartilage was studied macroscopically and microscopically at 3-month intervals. Cartilage changes 3 months after meniscectomy were more pronounced than after meniscal repair or than in untreated lesions. However, meniscal repair did not reverse the cartilage changes.

Resorption of intraarticular diffusible and microcolloid tracers. Rabbit studies of normal and synovitic knees

The resorption of two radiotracers (99mtechnetium-labeled microcolloid particles to study lymphatic transport and 51 chromium-EDTA to study diffusion) from the knee joint and the subcutaneous tissue of rabbits was investigated simultaneously. In 12 rabbits, synovitis was induced in the right knee 6 weeks or 3 months before the investigation; 6 rabbits served as controls. The final number of Tc-particles in the normal knees and in the subcutaneous tissue in the three groups did not differ; but removal from the synovitic knees was increased. The final number of Cr-EDTA particles did not differ within or between groups. The initial decrease was highest in the knees with acute synovitis (P less than 0.05). The results indicate (1) that in synovial tissue lymphatic transport is of little importance, (2) that leakage through the synovial membrane increases in synovitis, and (3) that a subcutaneous depot can be used as a reference instead of injections into a normal knee.

Repair of three-month-old experimental meniscal lesions in rabbits

Repair of three-month-old longitudinal meniscal lesions in the central avascular portion of the knee joint was investigated in 18 rabbits. Three months after a longitudinal incision was made in the avascular portion of the meniscus, no healing was observed. At that time a full-thickness radial cut from the lesion to the joint capsule, without using synovial flaps or implants, was performed in ten of the 18 rabbits. Three months later, nine of the ten menisci had healed mainly with cartilaginous tissue, although the repaired areas were different from the normal fibrocartilage both histologically and at gross inspection. Synovitis with hyperplasia of the lining cells, which was present in all cases at the time of repair, may play an important role in the healing process.

Lymphatic transport from normal and synovitic knees in rabbits

The resorption pattern of synovial fluid through the lymphatic system from normal and synovitic knee joints in rabbits was studied with 99mtechnetium-rhenium-sulfur colloid injected intraarticularly and monitored for 14 hours with a gamma camera. On the normal side the regional lymph nodes were visualized after 1 hour and after 14 hours still 75 percent activity remained in the knee. In the synovitic knees no lymphatic transport could be detected; and the radiotracer was unstable with rapid liberation of technetium, which was excreted in the urine. This radiolysis was not found in vitro in synovitic joint fluid. The lymphatic transport from normal rabbit knees is low. We found a clear difference in lymphatic transport between normal and synovitic knee joints.

Measurements of pressure on the sole of the foot in plaster of Paris casts on the lower leg

Pressure on the sole of the foot inside three different types of plaster cast, used in treatment of fracture of the lower leg, was measured on six normal persons. No significant difference was found between these pressures in below-knee plaster, full length plaster including the thigh and patellar-tendon-bearing plaster. Only occasionally a relief in pressure was found in patellar-tendon-bearing plasters.

Porous-coated knee arthroplasty. A case report concerning bone ingrowth

The area of bone-metal interaction in uncemented implants is regarded by many investigators as the key to the success or failure of the implant. The nature of the interaction is poorly understood because the zone is technically difficult to visualize and analyze. In order to test the power of modern imaging, analyzing, and metallurgical methods in this context, a well-functioning porous-coated knee prosthesis (tibial component) removed from the knee of a 65-year-old man was sectioned and examined by light microscopy, roentgenogram, scanning electron microscopy, and radiologic energy dispersive analysis. Independently, these methods demonstrated that the prosthesis was held in situ by collagenous tissue between and below the metal pellets of the prosthesis. Calcified bone did not appear to interact with the prosthesis and is probably not a major factor for prosthesis fixation. The various analytic methods described are suitable and sufficient for further exploration on a larger scale of the zone of bone-metal contact in cementless implants.

Sonography in soft-tissue trauma of the shoulder

Seventy-five patients with soft-tissue trauma in the shoulder region were examined by ultrasonography. Normal conditions were found in 21 patients, distension of the acromioclavicular joint in 17, muscle hematoma or edema in 9, biceps tendinitis in 8, hematoma or partial rupture of the biceps tendon in 5, rupture of the biceps tendon in 1, and supraspinatus tendinitis or partial rupture in 14. A correlation was found between the sonography and clinical course; normal sonography was consistent with recovery in less than 1 week, whereas patients with pathologic changes in the supraspinatus or biceps tendon generally had symptoms for at least 1 month. We concluded that sonography is a useful diagnostic tool for evaluation of soft-tissue trauma in the shoulder.

Intraarticular lymphoscintigraphy of the human knee joint: a preliminary study

Intraarticular (knee) lymphoscintigraphy using 99mTc-nanocoll was performed in five patients with chronic synovitis. Scintigrams from the anterior and lateral view of the knee and of the iliac region were taken 1, 2, 4, and 22 hours after injection. The inguinal and iliac lymph nodes uniformly visualized in about 2 hours. Based on radioactivity in regional lymph nodes measured at prescribed time intervals, we were able to quantify lymph drainage from the knee joint. Lymphoscintigraphy is without complication and discomfort and is potentially useful to study synovial fluid reabsorption in joint diseases.

Collagen type III predominance in newborns with congenital dislocation of the hip

The collagen content and the relative distribution of collagen Types I and III were measured in umbilical cords from newborns with congenital dislocation of the hip (CDH) and healthy controls. The total content of collagen per mg dry tissue tended to be reduced. In newborns with CDH the collagen III/I ratio was higher than in the controls. If generalized, these alterations in collagen metabolism may explain the joint hypermobility seen in CDH. It is suggested that the redistribution of collagen Types III and I during normal fetal development and early infancy may be delayed in CDH.

Experimental osteoarthritis in the rabbit. I. Histological changes of the synovial membrane

Based on an experimental model of osteoarthritis in 42 full-grown rabbits the histological changes were studied during the development of osteoarthritis after operative induction of instability of the knee joint. The changes were followed from 2 week to 1½ years after the induction.

The first changes were observed at 1 week stage as a proliferation of the lining cells. During the time of observation additional changes were seen such as hypertrophy of villi, infiltrations with plasma cells and lymphocytes, increased vascularity and interstitial edema and fibrosis. Edema was only seen during the first months, later increasing fibrosis was predominant.

The first cartilage change was reduction of the staining ability, expressing depletion of GAG, this was seen already at the one week stage whereas morphological changes were present after 4–6 weeks.

It was concluded that the synovial membrane in this model shows changes that may contribute to the development of osteoarthritis.

The pathology of congenital metatarsus varus. A post-mortem study of a newborn infant

A case of congenital metatarsus varus from an autopsy of a newborn infant was explored. Contracture of the anterior tibialis muscle was present as well as alterations in size and shape of the first cuneiform bone. Furthermore, subluxations in the fore- and midfoot were observed, especially round the first cuneiform bone. It is concluded that congenital metatarsus varus may be classified as a subluxation followed by secondary bone changes and contractures in the soft tissues.

Depressive effects of acrylic cement components on bone metabolism. Isotope release and phosphatase production studied in vitro

In vitro methyl methacrylate bone cement components were found to depress the release of radioactive calcium and proline as well as the activity of both alkaline and acid phosphatases. These effects were dose dependent and reached levels observed for dead bone. These observations may reflect part of the pathogenesis of loosening of joint replacements involving the use of bone cement.

Changes of the fibrocartilage in navicular disease in horses. A histological and histochemical investigation of navicular bones

Histological and histochemical investigations of the fibrocartilage of facies flexoria from navicular bones of horses with navicular disease have shown alterations similar to those described in the hyaline articular cartilage in osteoarthritic joints.

[Effect of histamine H2-receptor antagonists on the hepatic elimination of drugs]

H2-blocking agents, such as cimetidine or ranitidine are used in numerous patients. This treatment is often associated with the co-administration of a variety of other drugs. From clinical observations and pharmacokinetic studies it is obvious that even short-term treatment with therapeutic doses of cimetidine inhibits the hepatic elimination of antipyrine, warfarin, diazepam, desmethyldiazepam, chlordiazepoxide, propranolol, labetalol, metoprolol, phenytoin, carbamazepine, chlormethiazole, theophylline and caffeine. All these drugs are metabolized by cytochrome-dependent so-called phase I reactions. Cimetidine can interact with drug binding to the cytochrome P450 system leading to impaired drug metabolism. On the other hand drugs which are eliminated by glucuronidation (cytochrome independent phase II reaction), such as oxazepam and lorazepam are not affected by cimetidine. Other H2-blocking agents (ranitidine, oxmetidine) did not impair the elimination of antipyrine, warfarin, diazepam or propranolol. Furthermore, cimetidine and ranitidine might slightly reduce hepatic blood flow which could reduce the elimination of drugs with high hepatic clearance.

Serum concentrations of tobramycin after intraarticular administration. An experimental study in the rabbit

Serum concentration of the aminoglycoside tobramycin was followed for 120 min after intraarticular injection of 20 mg tobramycin in six rabbit knee joints. Highest concentration was observed after 15-30 min, and compared with the values after intramuscular injection the serum half life was equal. No pathological changes were observed by histological examination of the synovial membrane and articular cartilage. It was concluded that no damage of the joint has been demonstrated after intraarticular injection of tobramycin, but the serum concentration must be monitored due to the rapid transport from the joint cavity.

Influence of diphenylhydantoin on isotope release and bone enzymes in vitro

The acute effect of diphenylhydantoin isotope release in an in vitro system using mouse calvaries was studied. A depressive effect on bone resorption was found involving radioactive calcium as well as tritiated proline. Bone resorption and formation were further investigated by semiquantitative histochemistry. Depressed activity of both alkaline and acid phosphatase was found, indicating a direct inhibitory effect of diphenylhydantoin on bone turnover.