The role of intracoronary thrombus in unstable angina: angiographic assessment and thrombolytic therapy during ongoing anginal attacks

Intracoronary thrombus is regarded as a potentially important factor in the etiology of unstable angina, but the incidence of intracoronary thrombus in unstable angina has not been clearly defined. To determine the occurrence of intracoronary thrombus during ongoing angina pectoris, coronary angiography was performed during spontaneous ischemic attacks in 37 patients with prolonged rest angina. All patients exhibited significant (greater than 50%) stenoses of at least one major coronary artery. Of the 37 patients, 21 (57%) had intracoronary thrombus in major coronary arteries, whereas 14 (38%) had fixed narrowings without evidence of intracoronary thrombus and two exhibited coronary spasm. ST segment elevation was observed in 16 of 21 patients with thrombus and in all of the patients with coronary spasm, but all the patients with organic stable obstruction showed ST segment depression. Twenty of the 21 patients with thrombus improved after thrombolytic therapy with intracoronary injection of urokinase; obstructed arteries were reopened, or narrowings were attenuated, with relief of ischemic symptoms. In patients with fixed obstructions, the rate-pressure product during active symptoms was significantly higher than during an asymptomatic period, indicating that a transient increase in myocardial oxygen demand may contribute to the ischemic attack in these patients. A high incidence (71%) of recurrent symptoms was observed in patients with intracoronary thrombus even after successful thrombolysis, in contrast to a much lower incidence (36%) in those without intracoronary thrombus. Myocardial infarction within 4 weeks after catheterization was observed more frequently in patients with intracoronary thrombus (24%) than in those without thrombus (7%).(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of a DNA uptake reaction through the nuclear membrane of isolated yeast nuclei

Isolated yeast nuclei were able to incorporate 3H-labeled pJDB219 DNA in vitro in the presence of ATP and Mg2+. The number of plasmid molecules incorporated into each nucleus was calculated to be 60 under the conditions we used. Enzyme-histochemical staining of the incorporated biotinylated pJDB219 with streptavidin-biotinylated-peroxidase complex indicated a uniform distribution of the incorporated plasmids within each nucleus. After intranuclear incorporation, substrate pJDB219 DNAs (open and closed circular forms) were changed to the linear form and were weakly digested over the longer incubation period (over 60 min). Facile release of the once-incorporated plasmid DNA was never observable; discharge of the incorporated [3H]pJDB219 during a 60-min incubation was less than 5%. The addition of adenylyl-imidodiphosphate, N,N'-dicyclohexylcarbodiimide (DCCD), or quercetin inhibited in vitro DNA uptake reaction. DCCD and quercetin inhibited the nuclear ATPase and apparent protein kinase, respectively; hence, the involvement of these enzymes in the nuclear DNA transport system was suggested.

Interaction with phospholipids of a membrane thiol peptidase that is essential for the signal transduction of mating pheromone in Rhodosporidium toruloides

Interaction with phospholipids of a membrane thiol peptidase [referred to as trigger peptidase (TPase), T. Miyakawa et al. (1987) J. Bacteriol. 169, 1626-1631] that plays a key role in the signalling of a lipopeptidyl mating pheromone at the cell surface of pheromone-target cell (mating type a) of Rhodosporidium toruloides was studied. The activity of highly purified TPase which requires phospholipids was restored by reconstitution of the enzyme into liposomes prepared with phospholipids extracted from the yeast cell. The presence of Ca2+ was essential for both the reconstitution process and the catalytic reaction of TPase. Triton X-100 mixed micelles containing phospholipids also activated the enzyme. The specificity and stoichiometry of activation by phospholipids was investigated by determination of TPase in the presence of mixed micelles that contained defined classes and numbers of phospholipid molecules in the Triton X-100 micelles. It was demonstrated that TPase is activated by mixed micelles containing 2-6 molecules of phosphatidylserine or phosphatidylethanolamine. Other phospholipids of the membranes of this organism, such as phosphatidylcholine and phosphatidylglycerol, had little effect on activation, indicating that the amino group of the phospholipids may be required for the function of TPase. Direct evidence for the interaction of TPase and Triton X-100/phosphatidylserine mixed micelles was obtained by molecular sieve chromatography on Sephacryl S-200. These data established that a phospholipid bilayer is not a requirement for TPase activation, and that the purified enzyme can be activated by a relatively small number of phospholipid molecules of specific classes.

[Left ventricular asynergy in patients with impending myocardial infarction: two-dimensional echocardiographic assessment]

To determine the clinical significance of regional left ventricular asynergy in patients with impending myocardial infarction, we recorded two-dimensional echocardiograms (2DE) serially and performed coronary angiography immediately after the hospital admission in nine patients with initial impending infarction and their last anginal attacks were within 48 hours. Left ventricular asynergy on the first 2DE was observed in six of nine patients during symptom-free periods (Group A: LV asynergy group). Five of the six patients had significant coronary artery lesions (greater than or equal to 75% stenosis) in at least one major coronary artery. Intracoronary filling defects were detected in four of the five patients. Another three patients without asynergy (Group B) had significant fixed stenosis. Coronary artery spasm was observed in two patients during coronary angiography, but no patient had intracoronary filling defects. Intracoronary nitroglycerin (0.1-0.3 mg) reduced the severity of coronary artery narrowing in two patients. In addition, urokinase (240,000-480,000 IU) via the corresponding vessel (PTCR) in the remaining seven patients resulted in reduction in the severity of coronary artery stenosis in four patients, but not in the remaining three patients. Left ventricular wall movement in the asynergy group improved rapidly and no asynergy was observed by the seventh hospital day in five of the six patients. Successful PTCR treatment resulted in improvement of left ventricular wall movement. No asynergy was found in the non-asynergy group throughout their hospitalizations. These findings indicated that abnormal left ventricular wall movement is found in patients with impending myocardial infarction, even during symptom-free periods, but the wall movement gradually improves. The 2DE observations are useful for estimating the clinical status and for planning precise therapy for impending myocardial infarction.

Prostaglandin E1 in pulmonary hypertension of collagen disease

A 47-yr-old woman with low cardiac output and dyspnea due to pulmonary hypertension associated with rheumatoid arthritis was treated with two vasodilators. Although nicardipine, a Ca-channel blocking agent, reduced the pulmonary artery pressure (PAP), it reduced simultaneously the arterial BP, resulting in fluid retention with a low urine output and persistent high CVP. In contrast, prostaglandin E1 (PGE1) reduced successfully both the PAP and CVP. Although the BP decreased, a satisfactory urine output was maintained. The cardiac output increased from 3 to 4.5 L/min. PGE1 may help reduce reversible pulmonary hypertension of collagen disease.

Nucleotide sequence of the glucoamylase gene GLU1 in the yeast Saccharomycopsis fibuligera

The complete nucleotide sequence of the glucoamylase gene GLU1 from the yeast Saccharomycopsis fibuligera has been determined. The GLU1 DNA hybridized to a polyadenylated RNA of 2.1 kilobases. A single open reading frame codes for a 519-amino-acid protein which contains four potential N-glycosylation sites. The putative precursor begins with a hydrophobic segment that presumably acts as a signal sequence for secretion. Glucoamylase was purified from a culture fluid of the yeast Saccharomyces cerevisiae which had been transformed with a plasmid carrying GLU1. The molecular weight of the protein was 57,000 by both gel filtration and acrylamide gel electrophoresis. The protein was glycosylated with asparagine-linked glycosides whose molecular weight was 2,000. The amino-terminal sequence of the protein began from the 28th amino acid residue from the first methionine of the putative precursor. The amino acid composition of the purified protein matched the predicted amino acid composition. These results confirmed that GLU1 encodes glucoamylase. A comparison of the amino acid sequence of glucoamylases from several fungi and yeast shows five highly conserved regions. One homology region is absent from the yeast enzyme and so may not be essential to glucoamylase function.

Mutagenicity modulating effect of quercetin on aromatic amines and acetamides

The effect of quercetin on the mutagenicity of 32 kinds of aromatic amines and their acetamides were investigated using Salmonella typhimurium TA98 with a mammalian metabolic activation system (S9 mix). Quercetin enhanced the mutagenicity of the tricyclic aromatic amines (aminofluorene, aminoanthracene and aminophenanthrene) and their acetamides by 1.2-5.9-fold. Whereas, quercetin depressed the mutagenicity of aniline derivatives, biphenyl derivatives, and bi- and tetra-cyclic amino derivatives. The modulation of mutagenicity of Trp-P-1, Trp-P-2, Glu-P-1 and Glu-P-2 (heterocyclic amines) by quercetin were liable to be affected by the content of S9 in the S9 mix. It seems that quercetin does not have the same effect as norharman, because quercetin did not enhance the mutagenicity of aniline. It is suggested that the modulation of the mutagenicity of aromatic amines and acetamides is caused by the modulation of the balance between the mutagenic activation and inactivation in the metabolism of these amines and acetamides in the presence of quercetin. In this modulation, quercetin may participate through its effects on the promotion of N-hydroxylation and the inhibition of arylhydroxylation and transacylation. The presence of tricyclic aromatic rings of amines and acetamides is a structural requirement for the mutagenicity enhancement by quercetin.

Nucleotide sequence of the alpha-amylase gene (ALP1) in the yeast Saccharomycopsis fibuligera

The complete nucleotide sequence of the secretable alpha-amylase gene ALP1 from the yeast Saccharomycopsis fibuligera has been determined. The ALP1 DNA hybridized to a polyadenylated RNA of 2.0 kilobases. A single open reading frame encodes a 494-amino acid protein which is highly homologous with alpha-amylase (Taka-amylase) of a fungus Aspergillus oryzae.

Activation and cleavage of the carbon-cobalt bond of adeninylethylcobalamin by diol dehydrase

Adeninylethylcobalamin (AdeEtCbl) underwent cleavage of the C-Co bond by interaction with apoprotein of diol dehydrase from Klebsiella pneumoniae ATCC 8724, although this analog was quite inactive as coenzyme. Spectroscopic observation indicates that AdeEtCbl was converted to the enzyme-bound hydroxocobalamin without intermediates. The conversion was stoichiometric (1:1) and obeyed the second-order reaction kinetics (k = 0.027 min-1 microM-1 at 37 degrees C) depending upon concentrations of apoprotein and AdeEtCbl. This suggests that the complex formation is the rate-determining step and that AdeEtCbl undergoes rapid C-Co bond cleavage once it binds to the apoenzyme. Substrates and oxygen did apparently not affect the rate of the C-Co bond cleavage. The experiments using [adenine-U-14C]AdeEtCbl and [1(3)-3H]glycerol demonstrated that 9-ethyladenine was the only product formed from the adeninylethyl group of AdeEtCbl during the conversion and that an additional hydrogen atom in the 9-ethyladenine is not derived from the substrate. 1H NMR measurement of the 9-ethyladenine formed enzymatically from AdeEtCbl and DL-1,2-[1,1,2-2H3]propanediol also led to the same conclusion. All of these results indicate that the C-Co bond of AdeEtCbl is activated by diol dehydrase and undergoes heterolysis forming Co(III) and a carbanion or a carbanion-like species, in clear contrast to the homolysis of the C-Co bond of adenosylcobalamin in the normal catalytic process. 9-Ethyladenine formed remained tightly associated with the enzyme. Longer chain homologs, i.e. adeninylpropylcobalamin, adeninylbutylcobalamin, and adeninylpentylcobalamin did not undergo such cleavage of the C-Co bond by diol dehydrase.

Mutagenic reactivities of 3,4-dinitrobiphenyl derivatives

3,4-Dinitrobiphenyl derivatives were mutagenic in Salmonella typhimurium TA98, TA98/1,8-DNP6 and in TA98NR. We describe here the specific reactivity of 3,4-dinitrobiphenyl derivatives with diluted sodium hydroxide solution and the determination of the amounts of released nitrous ion. 3,4-Dinitrobiphenyl derivatives begin to release nitrous ions when treated with NaOH solution at a concentration of 10(-3) N. The behavior of 4NQO and o-dinitrobenzene was the same as that of 3,4-dinitrobiphenyl derivatives. The residues of 3,4-dinitrobiphenyl derivatives, after releasing nitrous ions, were estimated to be hydroxy-nitrobiphenyls, as by GC/MS, we found the formation of o-nitrophenol in the reaction mixture of o-dinitrobenzene with aqueous NaOH solution. 3,4,4'-Trinitrobiphenyl, 3,4,3',4'-tetranitrobiphenyl and 4NQO had reduced mutagenic potency in Salmonella typhimurium TA98 following treatment with diluted NaOH. In order to elucidate the ultimate forms of 3,4-dinitrobiphenyl derivatives, we investigated the reaction of o-dinitrobenzene as a basic model substance of 3,4-dinitrobiphenyl, with nucleic bases in the presence of NaOH in nonaqueous solvent. o-Nitrophenyl guanine and adenine adducts were obtained.

Mucin-carbohydrate directed monoclonal antibody

To raise monoclonal antibodies recognizing cancer-associated alterations of the carbohydrate structure of glycoproteins, Balb/c mice were immunized with human colonic cancer cells (LS 180 from ATCC). One of the generated hybridomas produced a monoclonal antibody that bound to the carbohydrate moiety of mucin-type glycoproteins from LS 180. The antibody did not bind to glycoproteins from another colonic cancer cell line, SW 1116, or to glycolipids from any of the colonic cancer cell lines. The antibody bound to ovine and bovine submaxillary mucins (OSM and BSM). NeuAc alpha 2----6Ga1NAc seemed to be involved in the epitope.

Gene fusion is a possible mechanism underlying the evolution of STA1

DNA from the STA1 (extracellular glucoamylase) gene of Saccharomyces diastaticus was used as a probe to enable the cloning by colony hybridization of three DNA fragments from Saccharomyces cerevisiae; these were designated S1, S2, and SGA (intracellular, sporulation-specific glucoamylase gene). To examine the evolutionary relationship among these sequences at the nucleotide level, we sequenced S2, S1, SGA and compared them with STA1. These data and RNA blot analysis revealed that the following regions of STA1 were highly conserved in S2, S1, and SGA: upstream regulatory sequences responsible for transcription, a signal sequence for protein secretion, a threonine- and serine-rich domain, and a catalytic domain for glucoamylase activity. These results suggest that an ancestral STA gene was generated relatively recently in an evolutionary time scale by the sequential fusions of S2, S1, and SGA, with S1 functioning as a connector for S2 and SGA. We describe a model for the involvement of short nucleotide sequences flanking the junctions in the gene fusions.

Purification and characterization of a Ca2+-dependent membrane peptidase involved in the signaling of mating pheromone in Rhodosporidium toruloides

A mating-type-specific, membrane thiol peptidase (referred to as trigger peptidase) that seems to play a key role in the transmembrane signaling of the lipopeptidyl mating pheromone rhodotorucine A at the cell surface of mating type a cells of Rhodosporidium toruloides (T. Miyakawa, M. Kaji, T. Yasutake, Y.K. Jeong, E. Tsuchiya, and S. Fukui, J. Bacteriol. 162:294-299, 1985) was purified to homogeneity and characterized. The following lines of evidence support the contention that the enzyme we purified was the trigger peptidase: the identical specificity of hydrolysis at the Arg-Asn sequence of rhodotorucine A and the sensitivity of the reaction to sulfhydryl-blocking reagents; the identical specificity for the substrate, with a strict requirement for the presence of the lipid moiety; and the absence of the corresponding activity in the pheromone-producing strain (mating type A) and in a sterile mutant strain, M-39 (type a), that lacks trigger peptidase activity in vivo. The apparent molecular weight of trigger peptidase was estimated to be 68,000 by Sepharose 6B gel filtration in the presence of octylglucoside and 63,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Trigger peptidase alone was inactive but exhibited enzymatic activity with the simultaneous addition of Ca2+, membrane phospholipids, and a nonionic detergent such as octylglucoside. The concentration of Ca2+ required for maximum activation was approximately 1 mM. Only Mn2+ could replace Ca2+ at comparable concentrations. Among the phospholipids tested, only phosphatidylserine and phosphatidylethanolamine supported trigger peptidase activation. Solubilized trigger peptidase was strongly inhibited by antipain and phosphoramidon.

Mutagenicity-enhancing effect of quercetin on the active metabolites of 2-acetylaminofluorene with mammalian metabolic activation systems

The effects of quercetin on the mutagenicity of 2-acetylaminofluorene (AAF) and its 3 active metabolites, N-hydroxy-AAF (N-OH-AAF), aminofluorene (AF) and N-acetoxy-AAF(N-OAc-AAF) were investigated. The mutagenicity assays were carried out with Salmonella typhimurium TA98, and S9, microsomes and cytosol were used as metabolic activation systems. In the presence of S9, quercetin enhanced the mutagenicity of AAF, N-OH-AAF, AF and N-OAc-AAF by 6.9-, 4.3-, 3.6- and 3.9-fold, respectively. Quercetin enhanced the mutagenicity of these substrates with microsomes, whereas it depressed the mutagenicity of these substrates with cytosol. From these results, it seemed probable that quercetin promotes the N-hydroxylation and deacetylation in the microsomes, whereas it inhibits the deacetylation in the cytosol. It was shown that in the metabolism of AAF and its metabolites, quercetin modulates the balance between the mutagenicity activation and inactivation processes, which is catalysed by the enzymes in the microsomes and cytosol, and causes enhancement of the mutagenicity of AAF.

Inhibition of membrane Ca2+-ATPase in vitro by mating pheromone in Rhodosporidium toruloides, a heterobasidiomycetous yeast

Direct addition of physiological concentrations of rhodotorucine A, a lipopeptide mating pheromone of Rhodosporidium toruloides, to the particulate fraction of the target cell strongly inhibited Ca2+-ATPase activity. The pheromone effect was mating-type specific. Membrane Ca2+-ATPase solubilized by a nonionic detergent and further purified by calmodulin-affinity chromatography was also inhibited by the pheromone. Rhodotorucine A S-oxide, a biologically inactive analogue, had no effect on Ca2+-ATPase. The results suggested that the inhibition of membrane Ca2+-ATPase is a critical event in the signaling of mating pheromone and the inhibition of membrane Ca2+-pump could be responsible for the pheromone-induced rapid raise of intracellular Ca2+ concentration reported.

Immediate and long-term prognoses of acute myocardial infarction: analysis of determinants of prognosis

In order to investigate the immediate and long-term prognoses of acute myocardial infarction, we followed up 790 consecutive patients who were admitted to the Sakurabashi Watanabe Hospital within 24 hours after the onset of infarction from January 1975 to December 1984 and evaluated early mortality, cumulative survival rate after discharge, cause of death and occurrence of recurrent myocardial infarction during follow-up. Early mortality (within 30 days after the onset) in all patients was 17.6% and declined serially in the most recent five years. Pump failure was the most common cause of death, followed by cardiac rupture and arrhythmias. Age, gender (female), presence of a previous infarct and anterior infarction were important contributing factors to the immediate prognosis. One hundred and thirty-five of the 651 patients who survived one month after the onset of infarct died during the follow-up period (mean follow-up interval: 41.0 +/- 29.9 (SD) months). Cumulative survival rates calculated by the life-table method at one and 5 years after the onset were 91.0% and 76.0%, respectively, and the average annual mortality in the first 5 years was 4.8%. Age and reinfarction were the important determining factors of long-term prognosis. Recurrent myocardial infarction, pump failure and sudden cardiac death were common causes of late death. One hundred and two reinfarctions in 93 patients occurred during the follow-up period. Thirty-two of 93 patients (34.4%) died due to fatal reinfarction. These results indicate that the immediate prognosis of acute myocardial infarction has improved serially, but the long-term prognosis is still poor.(ABSTRACT TRUNCATED AT 250 WORDS)

2,7-Diamino-3,8-dimethylphenazine as the major mutagenic product from the reaction of 2,4-diaminotoluene with hydrogen peroxide

The mutagenicity of 2,4-diaminotoluene (DAT) in Ames's Salmonella/microsome test was remarkably enhanced by treatment with hydrogen peroxide. Therefore, identification of the major mutagenic reaction product of 2,4-DAT with hydrogen peroxide at room temperature has been performed. Red precipitates were produced in a 2-day reaction mixture and were column chromatographed on silica gel. 5 fractions having mutagenic potency were obtained. The red crystalline needles, obtained as the major reaction product, were separated from fraction 2 and were subjected to high resolution mass spectrometry, 1H- and 13C-NMR spectrometry. The structure of the compound was determined to be 2,7-diamino-3,8-dimethylphenazine from physicochemical and chemical evidence. The compound induced 212 revertants/nmole in Salmonella typhimurium TA98 with 25 microliters S9 per plate.