Animal experiments demonstrated a significant suppressive effect of various calcium channel blockers on the formation of atherosclerotic lesions. Therefore, a prospective, placebo-controlled, randomized, double blind multicenter study was performed to investigate the inhibitory influence of the calcium channel blocker nifedipine (80 mg/day) on the progression of coronary artery disease in man. Study endpoints were changes of coronary morphology documented by coronary angiography with particular respect to the formation of new coronary stenoses. In 348 out of 425 patients included in the study, coronary angiograms were repeated after three years. The angiograms were standardized by induction of a maximal coronary vasodilation with high doses of nitrates and by using absolutely identical angiographic projections. Quantitative analysis of coronary cineangiograms was performed with the computer-assisted contour detection system CAAS. Parameters were mean and minimal diameter of all segments and minimal stenosis diameter, percent diameter stenosis, length and plaque area of all stenoses. Continuous intake of study medication was registered in 282 patients, 134 on nifedipine and 148 patients on placebo. In these patients, a total of 3808 coronary segments with 893 stenoses (greater than or equal to 20% diameter reduction in at least one angiographic projection) were compared on the baseline and follow-up cineangiograms. The changes in all angiographic parameters analyzed averaged over all patients by considering all angiographic projections analyzed, indicated significant progression of the disease (p less than 0.006). The average changes in all parameters were even about three times more profound, when in the individual patients only the respective projections indicating the maximal changes were considered for the calculation (p less than 0.001). However, with neither of these two analysis modes, the differences in progression between the treatment groups were statistically significant. In the follow-up angiograms, a total of 196 new coronary lesions (185 stenoses, 11 occlusions) were found at previously normal arterial sites. In patients on nifedipine, an average of only 0.58 new lesions per patient were detected versus 0.80 lesions per patient on placebo (-27%; p = 0.031). INTACT is the first prospective angiographic trial on the progression of coronary artery disease using computer-assisted quantitative coronary angiography in such a high number of patients. All parameters analyzed indicated significant progression of coronary artery sclerosis. Nifedipine had no influence on the progression of preexisting coronary stenoses, but inhibited significantly the formation of new angiographically recognizable lesions. Further prospective coronary angiographic trials with calcium channel blockers using a comparably exact method are needed to confirm the results of this study.

Cineangiography↗

PubMedDate not supplied

Absorption and transport of radioactive tracers in the midgut of the malaria mosquito, Anopheles stephensi.

Three radiolabeled substances were mixed with fresh heparinized mouse blood and fed to female Anopheles stephensi through a chicken crop membrane. Resorption and transport in the anterior (A) and posterior (P, stomach) parts of the midgut were investigated by means of electron microscopic autoradiography. Digestion products of 125I-labeled bovine serum albumin (BSA) were resorbed only in the P-part, showing a biphasic pattern with maximal values 4 and 18 hr after feeding. Uptake of 3H-labeled amino acids started immediately after feeding in both midgut parts. [14C]glucose was mainly absorbed in the P-part. Labeled carbohydrate storage deposits formed during the initial phase of digestion and were mobilized around 36 hr after feeding. After feeding the mosquitoes on 125I-BSA, oocyte protein yolk spheres and abdominal cuticle became labeled. Ingestion of 3H-labeled amino acids caused the formation of silver grains over follicles and fat body lipids. Feeding on [14C]glucose resulted in labeled fat body carbohydrates and oocyte protein yolk spheres.

Animals↗

PubMedDate not supplied

Binding of lectins to culture and vector forms of Trypanosoma rangeli Tejera, 1920 (Protozoa, Kinetoplastida) and to structures of the vector gut.

Culture forms of Trypanosoma rangeli could be agglutinated with Canavalia ensiformis (Con A) lectin and, less effectively with Pisum sativum agglutinin (PEA), at a concentration of 200 micrograms/ml. Ricinus communis agglutinin I (RCA I) agglutinated trypanosomes only if they were not previously washed with physiological Ringer's solution. Three other lectins did not react with the same parasite forms. Direct or indirect lectin-gold labeling techniques were applied to LR-White embedded thin sections of T. rangeli culture forms and to forms in the gut, hemolymph, and salivary glands of Rhodnius prolixus. Under these conditions, Con A was the only lectin out of 9 that bound to the surface of trypanosomes from culture and from the bug hemolymph. Con A did not react with any midgut or salivary gland forms. The preservation of the biological activity of the lectin-gold complexes that did not bind to the parasite surface was confirmed by reactions with structures of the invertebrate host.

Agglutination Tests↗

PubMedDate not supplied

Comparative chromatin analysis of Trypanosoma congolense.

The chromatin of Trypanosoma congolense was analyzed by electron microscopy. The chromatin is organized as nucleosome filaments but does not form a 30 nm fiber. There are five groups of histones, including a histone H1-like protein, which as a molecular weight within the range of the core histones, and is extremely hydrophilic. Weak histone-histone interaction, a typical feature of trypanosome chromatin, was found. These results are similar to those for T. cruzi and T. b. brucei, but differ significantly from those for higher eukaryotes. The results confirm the model of trypanosome chromatin, and support the theory of their early separation from the other eukaryotes during the evolution. T. congolensis is an excellent model for chromatin research on trypanosomes, because it is easy to cultivate and its chromatin has, a relatively high stability, compared to that of other trypanosomes.

Animals↗

PubMedDate not supplied

[Results of the HB-89 Study in treatment of malignant epithelial liver tumors in childhood and concept of a new HB-94 protocol].

94 children with a primary liver neoplasm were registered in the Cooperative Pediatric Liver Tumor Study HB-89 of the GPOH from 1988 to 1992. 64 of these had a hepatoblastoma (HB), 12 a hepatocellular carcinoma (HCC), 2 a sarcoma and 16 a benign tumor. 51 (80%) patients with an HB were 6 to 36 months of age, 9 with an HCC above 10 years. Initial serum-alpha-fetoprotein (AFP) was elevated in 51 HB patients and exceeded the 3-fold of normal range in 45. Children with low (< 100 ng/ml) and very high (> 1,000,000 ng/ml) levels had a significantly worse prognosis than those with intermediate values (p = 0.0014). AFP was moderately elevated in 9 HCC patients. All other tumor markers were only irregularly above normal range. 48 (77%) of HB patients survived, 45 (73%) are tumor free. All of 18 stage I and 4/5 stage II patients are in remission. After chemotherapy 30/36 stage III HBs and 2/5 stage IV HBs could be resected, 9 of these patients suffered from tumor relapse. Disease-free survival was 100% for stage I, 80% for stage II, 68% for stage III and zero for stage IV HB (p = 0.0005). Surgical complications occurred after 8% of biopsies, 13% of limited primary resections and 25% of extended secondary resections. There was no perioperative death. The completeness of tumor resection at primary or delayed surgery correlated significantly with patients disease-free survival (p < 0.0001). Chemotherapy with ifosfamide, cisplatin and adriamycin was effective in HB. 203 courses were given in 61 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Biomarkers, Tumor↗

PubMedDate not supplied

Early and late atrial dysrhythmias after modified Fontan operation.

UNLABELLED: Occurrence of supraventricular tachycardia and sinus node dysfunction was investigated pre- and postoperatively by serial ECG and Holter monitors in 63 consecutive patients with univentricular circulation after modified Fontan operation (total cavopulmonary connection 39 patients, atriopulmonary connection 24 patients). Mean age at operation was 7.2 (0.1-20.3) years. Of the 63 patients, 14 (22%) had early (< 14 d) supraventricular tachycardia or sinus node dysfunction, which was not related to the type of operation. None of 9 patients with a preoperative mean right atrial pressure < or = 2.5 mm Hg had early supraventricular tachycardia or sinus node dysfunction in contrast to 16/54 patients (30%) with a preoperative mean right atrial pressure > 2.5 mm Hg. 6/63 patients died during the early (< 14 d) postoperative period. In only 1 child, death was related to a dysrhythmia (junctional ectopic tachycardia). During a mean follow-up of 2.5 years, 15/57 long-term survivors (21%) had late supraventricular tachycardia or sinus node dysfunction. Early supraventricular tachycardia/sinus node dysfunction was a predictor or late atrial dysrhythmias, as it occurred in 8 of the surviving 14 patients with early dysrhythmias in contrast to 4 children without early atrial dysrhythmias (p < or = 0.001). After creation of an atriopulmonary connection, 10/22 patients (45%) had late supraventricular tachycardia/sinus node dysfunction, but only 2/35 patients (6%) with a total cavopulmonary connection had late atrial dysrhythmias (p < 0.001). CONCLUSIONS: Early atrial dysrhythmias after the Fontan operation were related to preoperative hemodynamics. Early supraventricular tachycardia/sinus node dysfunction and the atriopulmonary type of Fontan connection were significant risk factors for late atrial dysrhythmias.

Child↗