A sensitive noninvasive method for monitoring successful liver-directed gene transfer of the low-density lipoprotein receptor in Watanabe hyperlipidemic rabbits in vivo.

Noninvasive tools to quantitate transgene expression directly are a prerequisite for clinical gene therapy. We established a method to determine location, magnitude, and duration of low-density lipoprotein (LDL) receptor (LDLR) transgene expression after adenoviral gene transfer into LDLR-deficient Watanabe hypercholesterolemic rabbits by following tissue uptake of intravenously injected (111)In-labeled LDL using a scintillation camera. Liver-specific tracer uptake was calculated by normalizing the counts measured over the liver to counts measured over the heart that represent the circulating blood pool of the tracer (liver/heart (L/H) ratio). Our results indicate that the optimal time point for transgene imaging is 4 h after the tracer injection. Compared with control virus-injected rabbits, animals treated with the LDLR-expressing adenovirus showed seven-fold higher L/H ratios on day 6 after gene transfer, and had still 4.5-fold higher L/H ratios on day 30. This imaging method might be a useful strategy to obtain reliable data on functional transgene expression in clinical gene therapy trials of familial hypercholesterolemia.

Intravenous administration of recombinant adenoviruses causes thrombocytopenia, anemia and erythroblastosis in rabbits.

BACKGROUND: Recombinant adenoviruses are highly efficient gene transfer vehicles but their administration to mammals is accompanied by a strong inflammatory response. The present study reports additional side effects observed during adenoviral gene transfer studies in rabbits. METHODS: Hematological and serological parameters, the course of viremia and the organ distribution were analyzed after in vivo administration of E1-deleted adenoviruses in rabbits. RESULTS: The systemic administration of a therapeutic dose of 5 x 10(11) infectious particles/kg (infusion time 20 min) led to an average reduction of 80-90% in the platelet count within 48 h. Full recovery took 10-14 days. Virus administration induced a strong but transient erythroblastosis (peaking 24 h after administration) which settled 48 h later. Normochromic anemia occurred over the next 10 days with hemoglobin levels dropping by about 40% to reach the lowest level 10 days after administration and taking two months for full recovery. Dose-dependent thrombocytopenia was also found in mice, but neither erythroblastosis nor anemia was observed (in equivalent doses). The hematological findings did not improve after local injection via the portal vein. Local and systemic administration led to a comparable course of viremia. Only minor differences were found in the biodistribution of viruses between local and systemic administration. Large amounts of viral DNA and transgene expression were found in the lungs, the kidneys and the ovaries, even after local administration via the portal vein. CONCLUSIONS: Local intravenous injection via the portal vein does not prevent systemic spread of viral vectors and the occurrence of vector-related side effects. The hematological changes observed in rabbits suggest the need for careful monitoring of hematological and rheological parameters in clinical trials.

[Oral longterm therapy with disopyramide phosphate in patients with atrial and ventricular arrhythmias (author's transl)]. / Orale Dauertherapie mit Disopyramid-Phosphat bei Patienten mit Vorhof- und Kammerarrhythmien.

The antiarrhythmic effect of longterm therapy with disopyramide phosphate (DP) was investigated in a single controlled trial in 34 patients. Of 11 patients with atrial fibrillation, 5 were successfully cardioverted to sinus rhythm with DP in the long run. In the treatment of extrasystole, the arrhythmia was eliminated or reduced by 75% in 15 of 23 patients. In 6 cases a moderate improvement was achieved and there was no change in 2. The average daily dose initially was 4.2 capsules, the maximum dose was 5.4, and for longterm therapy 4.3 capsules. With respect to its indications, DP is largely similar to quinidine, but in our experience it is characterized by better tolerance.

[Influence of molsidomine on exercise-ECG'S In coronary insufficiency (author's transl)]. / Wirkung von Molsidomin auf das Belastungs-EKG bei Koronarinsuffizienz.

Molsidomine was shown to have a strong pain-relieving action in 22 coronary patients investigated one hour after oral intake of 2 mg of the substance. During comparable maximal exercise load the ST interval lowering was reduced from an average of 0.22 mV to 0.09 mV (P less than 0.0005). At the termination of exercise it was still reduced from 0.23 mV to 0.12 mV (P less than 0.0005). At the same time the exercise tolerance increased from 570 to 717 Watt-minutes (P less than 0.0025). Pectanginal complaints were clearly reduced at the same exercise loads, 11 patients became symptom-free at the same load. Even when exercise loading was stopped at higher loads a decrease of the severity of angina pectoris could be shown. Seven patients became symptom-free at that stage. The heart rate was not influenced markedly at rest and during exercise. Systolic blood pressure was reduced from 135 mm Hg to 118 mm Hg (P less than 0.0005), and in comparable submaximal loads from 177 to 165 mm Hg (P less than 0.005).

Electrocardiographic changes in cardiomyopathic Syrian hamsters (strain BIO 8262).

Under ether anesthesia electrocardiograms were derived from Syrian hamsters (strain BIO 8262) suffering from cardiomyopathy and muscular dystrophy. In addition, ventricular weights and body weight were determined. Young hamsters -- not yet showing morphological signs of the cardiomyopathy with the exception of possible left ventricular hypertrophy -- demonstrated only a longer ventricular activation time than normal hamsters. With the onset of cardiac necrotization left axis deviation in frontal plane projection and right bundle branch blocks are developing in the cardiomyopathic hamsters followed by first degree atrioventricular conduction defects. During the late stage of the cardiomyopathy left bundle branch blocks are additionally arising, while left ventricular hypertrophy is disappearing. Since no overt heart failure is occurring in this strain of cardiomyopathic hamsters, gradual development of high degree conduction defects is assumed to terminate their lives. The electrocardiographic pattern of the hamster cardiomyopathy fits partly into that of human primary as well as secondary cardiomyopathy. Nevertheless, it seems to form an entity of its own, as arrhythmias, higher degree atrioventricular conduction disturbances, typical signs of ventricular or septal hypertrophy, abnormal P and Q waves, ST segment and T wave changes are lacking.

[Effect of proscillaridin-4'-methylether on pressure rise velocity in the left ventricle of patients with coronary heart disease (author's transl)]. / Die Wirkung von Proscillaridin-4'-methyläther auf die maximale Druckanstiegsgeschwindigkeit im linken Ventrikel von Patienten mit Coronarinsuffizienz.

In a randomized, controlled, double-blind study 2 groups of 7 patients each with coronary heart disease received either 1 mg methylproscillaridin (MP) a cardiac glycoside of the squill intravenously, or placebo to test the inotropic effect of MP. Pressures and dp/dt max were measured in the left ventricle before and after coronary angiography after an average of 62 min (60 to 70 min). There was a significant (p less than 0.05) increase of dp/dt max in the MP-group (Wilcoxon-Mann-Whitney test). Left ventricular enddiastolic pressure was decreased from 16.1 to 13.6 mm Hg in the MP-group, and increased in theplacebo group from 12 to 13.7 mm Hg (mean values). Thus, a positive inotropic effect of the glycoside may be assumed.

[The effect of disopyramide phosphate in extrasystole at rest and on exercise (author's transl)]. / Wirkung von Disopyramid-phosphat bei Extrasystolie in Ruhe und unter Belastung

The antiarrhythmic action of disopyramide phosphate was compared to placebo in a randomized double blind trial at rest and under physical exertion in two groups each of 10 patients with extrasystoles. The exercise was carried out on the bicycle ergometer in a recumbent posture in stages of 25 watts at 2 minutes each without a break to the limit of the individual. The extrasystoles were counted at fixed registration periods. It was shown that the number of extrasystoles in the disopyramide group was significantly lower in comparison to the placebo group (P less than 0.05).

[Characteristic electrolyte changes in the hereditary myopathy and cardiomyopathy of the Syrian golden hamster (strain BIO 8262) (author's transl)]. / Charakteristische Elektrolytveränderungen bei der erblichen Myopathie mit Kardiomyopathie des Syrischen Goldhamsters (Stamm BIO 8262)

In hamsters of differing ages suffering from a hereditary myopathy and cardiomyopathy (strain BIO 8262), the electrolytes sodium, potassium, calcium, and magnesium in serum, and several tissues were compared with appropriate controls. The determinations of the electrolytes were performed by atomic absorption spectrophotometry. An enormous accumulation of calcium in the necrotizing heart and skeletal muscle was the noticeable feature besides pronounced elevation of the sodium content in the myopathic skeletal muscle. While the latter refers mainly to an interstitial edema which is a consequence of the myopathy, the calcium accumulation is assumed to be an essential part in the cycle of pathologic events occurring in the hereditary disease: it seems to induce the necrotization.