Identification of connective tissue components in healing rat gingiva

Abstract – The aim of the study was to examine connective tissue fiber organization during healing of an incisional wound in rat molar gingiva. Forty rats 50 days old were divided into 10 experimental groups each comprising four animals. Following interdental incisions, healing periods of 11-20 days, and then ³H-proline injection, the animals were sacrificed and specimens prepared for light microscopy, autoradiography, and transmission electron microscopy. Isotope labeling with ³H-proline occurred over newly formed collagen in the path of incision, while preexisting tissue was unlabeled. Ultrastructurally, preexisting and new tissue were identified by measurement of collagen fibril thickness. The spatial relationship between new and remaining fibrous tissue in the transitional zone suggests that reunion is established by side-by-side alignment of new and severed fibrils.     

Incidence and Pattern of Ventricular Late Potentials in the First Ten Days Following Acute Myocardial Infarction

In contrast to studies of late potentials (LP) during the chronic stage of myocardial infarction (MI), little has been published about signal averaged LP during the acute phase of MI. We therefore investigated the occurrence of LP during the first 10 days following acute MI in daily measurements of the signal averaged ECG. Thirty-three patients with acute MI defined by clinical, history, diagnostic electrocardiographic changes, and enzymatic evaluation were prospectively included in the study. Thirty-three percent suffered from anterior MI, 43% from inferior MI, and 24% had MI in both regions. Using the method of Simson, an LP was defined as a mean voltage of < 25 ±V in the last 40 msec of the filtered QRS complex. The incidence of LP ranged between 24% on the first day and 39% on day 6. There was no significant difference comparing the incidence of LP between consecutive days. Looking at the individual patient, only 3 patients exhibited a constant LP, 15 patients remained without LP, and 15 patients showed a variable incidence over the course of 10 days. There was no correlation between the incidence of LP and the localization of MI or the maximum level of the CK-MB isoenzyme.     

A 19-h spontaneous sleep period in idiopathic central nervous system hypersomnia

Reports of prolonged sleep periods in idiopathic central nervous system hypersomnia, as shown by ad libitum sleep recordings, are rare. A patient with idiopathic hypersomnia with extremely long sleep periods and sleep drunkenness after awakening is described. Polysomnographic recordings showed a spontaneous sleep period of 19.4 h and a normal Multiple Sleep Latency Test. These polysomnographic findings are clearly abnormal but essentially different from those of narcolepsy. Unlike narcolepsy, ‘idiopathic hypersomnia’ does not seem to be a distinct clinical entity but a category for different heterogenous subtypes.     

Magnetocardiography and 32-Lead Potential Mapping

Repolarization of the Magnetocardiogram. Signals from 37 magnetocardiographic sensors and simultaneously recorded 32 ECG leads were obtained in three healthy male subjects (including two reinvestigations). After recordings at rest, the heart rate was increased by pharmacologic stress (117 to 142 beats/min). Comparison of the repolarization of rest and stress showed substantial changes in the magnetocardiogram (MCG) up to T wave inversions during stress. In the ECG only junctional ST-T segment shifts were present. Eor quantification, correlation coefficients between pairs of rest and stress MCG and rest and stress ECG distributions were calculated for the same time instant at the beginning of T wave under rest and stress conditions. In addition, equivalent electrical current dipole moment and magnetic dipole moment vectors were calculated from the MCG, and their cbange from rest to stress evaluated. Correlation coefficients for MCG comparison ranged from 0.3 to 0.5; ECG comparison suggested much less change from stress, ranging from 0.7 to 1.0. Current dipole moment changes at T wave onset were marginal; in contrast, the magnetic dipole moment changed substantially. Since the magnetic dipole refiects vortex currents, changes in its intensity and/or orientation during repolarization suggest this as the biophysical basis of the striking difference in the response of the MCG and ECG to pharmacologic stress. Normal ECG findings at rest and under stress in healthy subjects support the conclusion that the repolarization changes in the MCG were of nonpathologic origin.     

Efficacy and Safety of Thrombolysis with Intravenous Streptokinase Initiated Prior to Ambulance Transport from Community Hospital to Tertiary Health Care Center

We studied the safety and efficacy of thrombolytic therapy for acute myocardial infarction initiated prior to ambulance transport. Two treatment regimens were compared in a prospective design: 40 patients (group A) received intravenous streptokinase 5 ± 10⁵ IU (SK-IV) prior to and during ambulance transport and were compared with 36 patients (group B) in whom the same dosage of streptokinase was given after arrival in our hospital. In all patients immediate coronary angiography was performed, followed by intracoronary streptokinase administration. Infarct size was assessed by cumulative release of α-hydroxybutyrate dehydrogenase. Apart from three episodes of ventricular fibrillation no procedure-related complications occurred during transport. Median time to SK-IV was 70 minutes in group A versus 125 minutes in group B (P < 0.001). At first visualization the infarct-related vessel was patent in 23 patients (58%) in group A and in 6 patients (17%) in group B (P < 0.001). Anterior wall infarction median infarct size in group A was 32% smaller than that in group B (P < 0.05). We conclude that SK-IV started before ambulance transport is safe, accelerates early reperfusion rate, and consequently leads to a further limitation of infarct size in patients with anterior wall infarction. (J Interven Cardiol 1989:2:3)     

Pregnancy and Cesarean Section in a Patient with a Rate-Responsive Pacemaker

The function of a rate-responsive pacemaker was monitored during pregnancy and cesarean section in a woman with complete atrioventricular block. The observations during pregnancy were compared to similar observations obtained in a pregnant normal woman of comparable age, height and weight, and in 12 normal women during elective cesarean section. During pregnancy, the heart rate increased in the normal woman, whereas the pacing rate in the woman with the implanted pacemaker was unchanged. Fetal movement caused an increase in pacing rate in the 37th week of gestation, whereas the heart rate in the normal woman did not respond. During cesarean section the pacing rate was generally within the mean +/- 1 SD for normal women.     

BETA-TRACE PROTEIN CONCENTRATION IN CSF IN NEUROLOGICAL DISORDERS

Beta-trace protein constitutes about 7 % of the total cerebrospinal fluid (CSF) protein concentration. In the present study the concentration of beta-trace protein in CSF has been determined in 59 "healthy" controls and in 174 patients suffering from various neurological diseases. The CSF concentration of beta-trace protein was found to increase with age. No statistically significant difference of the CSF beta-trace protein concentration could be found between patients suffering from various neurological diseases and healthy controls, with the exception of patients with cerebrovascular disease, where increased concentrations were found around the 5th week after the onset of the stroke. This increase was especially marked in patients with the most severe signs of a cerebrovascular lesion. Slightly higher CSF beta-trace protein concentrations were found in patients investigated within one month after an exacerbation of multiple sclerosis when compared with multiple sclerosis patients later investigated. A parallelism between increased concentrations of CSF beta-trace protein and the severity of myelin degradation is postulated.     

Particularities of Dual Chamber Pacemaker Therapy in Patients after Orthotopic Heart Transplantation

Since August 1981, 33 orthotopic heart transplantations were performed in our hospital. Three of these patients (9%) had sinus bradycardias with rates as low as 30 beats/min; they were treated by implantation of a dual chamber pacemaker. These patients had two atria as a result of orthotopic heart transplantation, but only the donor atrium was suitable for positioning the atrial lead. In the postoperative period, some nonsurgical complications were observed in one patient who developed atrial fibrillation which we treated with drugs. A cyclosporin-evoked tremor produced several asystoles due to false inhibition by myopotential interference in the VVI mode. During an episode of acute rejection combined with renal insufficiency, loss of atrial and ventricular sensing occurred. The other patients showed no pacemaker-related complications. Our findings in this unique population of pacemaker patients are discussed.