The blood flow recorded in the center of the left ventricle (LV) during the isovolumic relaxation period, i.e., isovolumic relaxation flow (IRF), was evaluated by pulsed Doppler echocardiography. The subjects consisted of 17 normal persons, 12 patients with angina pectoris (AP), 63 with old myocardial infarction (OMI), 16 with hypertrophic cardiomyopathy (HCM) and 16 with dilated cardiomyopathy (DCM). In the normal subjects, the IRF showed a laminar flow and it was directed from the center of the LV toward the apex. The maximum velocity of the IRF coincided with the second heart sound. In the patients with heart diseases, the IRF was classified into three patterns. Type A, in which the IRF was directed toward the apex of the LV: This pattern was observed in two different patient groups from the standpoint of LV wall motion and LV ejection fraction (LVEF). One group had either a normal LVEF without wall motion abnormalities or normal LVEF with a small area of abnormal wall motion in the anterior and/or apical portions. The other group had various LVEF with abnormalities of wall motion in the posterior and/or inferior portions. The duration of the IRF in type A was prolonged in AP (142 +/- 35 msec), OMI (152 +/- 14 msec), HCM (166 +/- 33 msec) and DCM (171 msec) when compared with those of the normal subjects (119 +/- 35 msec). The acceleration time (time interval from the beginning of the IRF to the point of the maximum flow velocity) in the normal subjects was 25 +/- 8 msec, but they were prolonged in AP (37 +/- 12 msec), OMI (59 +/- 22 msec), HCM (64 +/- 18 msec) and DCM (58 msec). The acceleration rate (increment of the flow velocities per sec) was significantly decreased in AP (8.9 +/- 3.2 m/sec2), OMI (4.5 +/- 2.7 m/sec2), HCM (4.5 +/- 1.1 m/sec2) and DCM (3.7 m/sec2) when compared with those of the normal subjects (12.6 +/- 4.0 m/sec2). Type B, in which the IRF was directed away from the LV center to the base of the LV: The patients with this type had slightly depressed LVEF with moderately extended abnormalities of wall motion in the anterior and/or apical portions. Type C without discernible IRF: The patients with this type had severely depressed LVEF with generalized abnormalities of wall motion. It was concluded that the patterns of the IRF are affected by regional wall motion and the IRF seems to be caused by LV relaxation.

Angina Pectoris↗

PubMed1984

Unusual heterogeneity of the 5'-termini of human adenovirus type 2 early region E2 mRNA.

The 5'-terminal structures of human adenovirus type 2 (Ad2) early region 2 (E2) mRNA were investigated. The E2 transcription unit has several interesting properties, including the presence of a TATA-like box that matches the consensus sequence poorly, delayed transcription during early stages of infection, and a switch in promoter recognition late after infection. E2-specific RNA, 5'-labeled in vitro to high specific activity was analyzed. Purified E2 mRNA was digested with RNase A or RNase T1 and the resulting oligonucleotides were resolved by two dimensional paper electrophoresis-homochromatography. Remarkably, as many as sixteen 5'-terminal RNase A oligonucleotides were identified and their sequences were deduced. The most common 5'-termini in the RNase A digest were p(m6)AmCp, p(m6)AmA(m)Cp, pGmA(m)Cp, and p(m6)AmG(m)Cp. Two RNase A oligonucleotides originated from the E4 promoter region, consistent with electron microscopic observations. The sequence encoding these potential initiation sites covered about 90 nucleotides. Eleven of the sequences of the 5'-terminal RNase A oligonucleotides were aligned with the Ad2 DNA sequence in the Ad2 E2 promoter region. If the heterogeneous termini in the E2 promoter region were generated by a process of transcription initiation, their existence cannot be explained by stuttering of RNA polymerase II. This suggests that the transcription of Ad early region 2 has features which differ from those of other Ad2 early gene transcription units. Perhaps this is due to the absence of a conventional TATA box which is believed to position the initiation site. Alternatively, it is conceivable that the E2 promoter represents an alternate class of RNA polymerase II promoters containing different signals with different requirements for activation and/or that an E1A gene product modifies transcription initiation.

Adenoviruses, Human↗

PubMed1984

Cell-free translation of adenovirus 2 E1a- and E1b-specific mRNAs and evidence that E1a-related polypeptides are produced from E1a-E1b overlapping mRNA.

We have characterized the polypeptides translated in vitro by mRNAs of early region 1 (E1) of human adenovirus (Ad) type 2. Poly (A+) polyribosomal RNA was isolated from early Ad2-infected cells, the viral specific mRNAs were selected by hybridization to Ad2 E1a and E1b DNA, and the mRNAs were translated in vitro using [35S]methionine as a labeled precursor with a rabbit reticulocyte lysate. E1a-selected mRNA was translated to the 45-58-kDa cluster of polypeptides. We show here that E1b-selected mRNA can also be translated to the 45-58-kDa cluster of polypeptides in addition to the major 19-kDa polypeptide. The E1b 58-kDa polypeptide was produced only at a low level unless E1b mRNA is fractionated before translation to enrich for the 58-kDa mRNA. Translation of E1b region-selected mRNAs that have been fractionated by size shows that the 22 S mRNA fraction is translated to at least the 53-58-kDa E1a-related polypeptides as well as to E1b 58- and 19-kDa polypeptides. Our experiments suggest that the 22 S mRNA fraction includes E1a-E1b overlapping mRNA which was translated to E1a-related polypeptides as well as E1b 22 S mRNA. When compared by two-dimensional gel electrophoresis and by tryptic peptide mapping, the cluster of polypeptides translated from E1a-selected mRNA and the cluster translated from E1b-selected mRNA were distinguishable. A possible explanation for this is discussed, based upon splicing sites of the E1a-E1b overlapping mRNA which would result in an amino acid sequence with a COOH-terminal end slightly different from that of E1a polypeptides.

Adenoviruses, Human↗

PubMed1984

Patterns of relapse of squamous cell carcinoma of the maxillary sinus.

Ninety-five M0 patients with squamous cell carcinoma of the maxillary sinus were treated mainly with combined surgery, radiation and chemotherapy. They were staged surgically according to the American Joint Committee TNM classification: 3 were T2N0, 55 T3N0, 27 T4N0 and 10 T3-4N1-3 patients. Relapse developed in 66 patients (69%): one (33%), 35 (64%), 22 (81%) and 8 (80%), respectively. All patients experienced relapse within 2 years after diagnosis. Local recurrence developed during the course of disease in 52 (79%) of the 66 patients who relapsed. Three patients with cervical relapse and one with local recurrence were successfully salvaged with rescue surgery. Local control achieved in 39 (41%) of the 95 patients: 2 (67%), 28 (51%), 7 (26%) and 3 (30%) in T2N0, T3N0, T4N0 and T3-4N1-3 patients, respectively. Autopsy findings of 17 patients are presented. An impact of computed tomography on staging of maxillary sinus tumors is discussed.

Adult↗

PubMed1984

Detection and determination of active metabolites of 1-(2-o-chlorobenzoyl-4-chlorophenyl)-5-glycyl-aminomethyl-3-dimethy l-carbamoyl-1H-1,2,4-triazole hydrochloride dihydrate, (450191-S), in rat tissues, using a radioreceptor assay for benzodiazepines.

1-(2-o-Chlorobenzoyl-4-chlorophenyl)-5-glycyl-aminomethyl-3- dimethylcarbamoyl -1H-1,2,4-triazole hydrochloride dihydrate, (450191-S), exhibits pronounced central nervous system (CNS) activities similar to those of benzodiazepines, but it has only low affinity for benzodiazepine receptors. However, when 450191-S was administered to rats at a dose of 10 mg/kg, brain extracts markedly inhibited [3H]diazepam binding to the receptors. Thin-layer chromatography (TLC), high performance liquid chromatography (HPLC), and radioreceptor assay (RRA) were used to isolate three metabolites that could inhibit [3H]diazepam binding prominently. These were identified by gas chromatography-mass spectrometry (GC/MS) as compounds having the triazolo-benzodiazepine skeleton. They showed high affinities for benzodiazepine receptors (Ki = 0.9 to 2.1 nM) and exerted potent pharmacological effects similar to those of 450191-S. In addition, their levels in the brain were sufficient to explain the pharmacological activity of 450191-S, which could not be detected in tissue extracts 15 min after administration. These results indicate that the pharmacological activity of 450191-S is largely due to the action of active metabolites, although some points remain to be elucidated to fully account for the large attenuation of the side effect (ataxia) compared with the major effects (anti-convulsant and hypnotic). We also determined the brain levels of metabolites following the administration of 450191-S and evaluated the extent to which each active metabolite contributes to the pharmacological activities of this drug.

Animals↗

PubMed1984

Facilitated transfer of cholesteryl ester between rough and smooth microsomal membranes by plasma lipid transfer protein.

The accessibility of intracellular membrane cholesteryl esters to removal was tested with plasma lipid transfer protein as a tool. Incubation of a mixture of non-radioactive smooth microsomes + rough microsomes prelabeled with cholesteryl ester resulted in slight movement (2-4%) of radioactive cholesteryl ester into smooth microsomes. With the addition of increasing amounts of plasma lipid transfer protein to the mixture, the % transfer of cholesteryl ester into smooth microsomes progressively increased until a plateau was reached at 14%. Movement of cholesteryl ester in the reverse direction was examined with non-radioactive rough microsomes as an acceptor and smooth microsomes prelabeled with cholesteryl ester as a donor. The pattern of the % cholesteryl ester transferred in the reverse and forward direction was almost identical in the presence of plasma lipid transfer protein, showing bidirectional movement of cholesteryl ester between membranes.

Animals↗

PubMed1984

Novel peptides with orally active and long-lasting antihypertensive activity.

A series of N-(P-substituted phosphinoyl)peptides were synthesized and their antihypertensive activities were tested in spontaneously hypertensive rats (SHR). Among them, N-(dibenzyloxyphosphinoyl)-L-Ala-L-Pro-L-Pro-OH showed the most potent and long-lasting antihypertensive activity in SHR when administered orally. Although the inhibitory activity of this peptide against the angiotensin-converting enzyme was about one-hundredth of that of Captopril, the antihypertensive activity in SHR was significantly higher and longer-lasting than that of Enalapril which has been reported to be the most potent agent among similar converting enzyme inhibitors.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed1984

[Evidence for the existence of inactive arterial renin in the rat].

Inactive renin in rat arterial walls was investigated according to the following experiments. Dialysis at pH 7.4 following dialysis at pH 3.3 of the arterial tissue resulted in a significant rise of renin activity, from a control value of 0.41 +/- 0.07 to 0.62 +/- 0.06 ng/ml/h (p less than 0.01). Treatment with trypsin of the arterial tissue caused a rapid and apparent increase in the renin activity at either 0 or 27 degrees C. The molecular weight of the active renin was estimated to be 32,000 or 39,000, while that of the inactive renin was found to be 36,000 or 44,000 on Sephadex G-100 gel filtration. The contents of the inactive renin varied with different segments of arterial wall. The ratio of inactive renin to total renin was the lowest in renal artery wall (0.32), while there was no significant difference in the ratio in other arterial walls (abdominal aorta, 0.87; thoracic aorta, 0.93; carotid artery, 0.96; mesenteric artery, 0.89; pulmonary artery, 0.92). These findings suggest that conversion of inactive renin into active renin can occur in arterial tissue, which, in turn, plays an important role in the local control of vascular tone. It seems that inactive renin found in the arterial wall is of local origin.

Animals↗

PubMed1984

Determination of peptidoaminobenzophenone (2-o-chlorobenzoyl-4-chloro-N-methyl-N'-glycylglycinanilide) and its metabolites in human plasma by capillary gas chromatography negative ion chemical ionization mass spectrometry--2.

The capillary gas chromatographic negative ion chemical ionization mass spectrometric assay of peptidoaminobenzophenone (2-o-chlorobenzoyl-4-chloro-N-methyl-N'-glycylglycinanilide) (1) and its three metabolites in human plasma reported in Part 1 was changed as follows: (1) the reagent gas was changed to ammonia from isobutane; (2) each unlabelled compound (1%) was added to the deuterium-labelled compound used as the internal standard; (3) all samples were injected in the splitless mode; (4) one more metabolite, lormetazepam, was determined; (5) day-to-day reproducibility was checked in the range of 1-50 ng ml-1. Points 1 to 3 improved the preciseness with small-sized samples. Calibration curves were prepared in the range of 0.5-50 ng ml-1. Plasma levels of compound 1 and its four metabolites in 10 volunteers were measured.

Gas Chromatography-Mass Spectrometry↗

PubMed1984

Intercellular junctions in odontoblasts of the rat incisor studied with freeze-fracture.

The morphology and distribution of various types of intercellular junctions were investigated in young odontoblasts. Gap junctions were found between odontoblasts as well as between odontoblasts and fibroblasts in the dental pulp. The junctions between odontoblasts were larger and more numerous than those between odontoblast and fibroblast, suggesting that the former may play an important role in regulating cellular activity and the latter may provide a pathway of low electrical resistance between odontoblast and nerve fibres. Irregularly-shaped gap junctions appeared as small aggregations of particles associated with a particle-free area and may indicate that the junction might not yet have been completely assembled. Tight junctions were observed at the distal ends of the young odontoblasts, arranged to form small maculae or faciae occludentes rather than belt-like zonulae. It is therefore not likely that the junction contributes to barrier function in the young odontoblasts. Although structures resembling typical desmosome were recognizable, this type of junction in odontoblasts is properly termed a desmosome-like junction from its morphological peculiarities.

Animals↗

PubMed1984

Augmentation of cholesterol esterification in the microsomal membrane by the removal of membrane-bound ribosomes.

Acyl-CoA: cholesterol O-acyltransferase (ACAT) activity in rough microsomes was enhanced (2-fold) by the removal (40%) of ribosomes from the microsomal membrane with RNase. Although EDTA was as efficient as RNase in the removal of ribosomes the stimulation (3.2-fold) of ACAT activity was even more, suggesting that additional effects were induced by EDTA. Reconstitution of EDTA-treated microsomes with ribosomes decreased the cholesterol-esterifying activity (40%) of the degranulated microsomes. Alternate possibilities were considered for the enhancement of ACAT activity by EDTA, namely, suppression of the hydrolysis of added palmitoyl-CoA substrate, the hydrolysis of cholesteryl ester, and the removal of metal suppressor of ACAT activity. Neither acyl-CoA hydrolase nor cholesteryl ester hydrolase activity was decreased after degranulation of microsomes. ACAT activity of EDTA-treated microsomes compared to the control was enhanced rather than suppressed after the addition of Ca2+, Mg2+, and Ba2+ ions whereas other metal ions (Co2+, Cu2+, Zn2+) almost completely suppressed ACAT activity in both the EDTA-treated and buffer-treated microsomes. It is concluded that the enhanced ACAT activity was largely due to the removal of ribosomes from the microsomal membrane.

Animals↗