Spin/orbital and magnetic quantum number selective magnetization measurements for CoFeB/MgO multilayer films

Spin selective magnetic hysteresis (SSMH) curves, orbital selective magnetic hysteresis (OSMH) curves and magnetic quantum number selective SSMH curves are obtained for CoFeB/MgO multilayer films by combining magnetic Compton profile measurements and superconducting quantum interference device (SQUID) magnetometer measurements. Although the SQUID magnetometer measurements do not show perpendicular magnetic anisotropy (PMA) in the CoFeB/MgO multilayer film, PMA behavior is observed in the OSMH and SSMH curves for the |m|  =  2 magnetic quantum number states. These facts indicate that magnetization switching behavior is dominated by the orbital magnetization of the |m|  =  2 magnetic quantum number states.

[Significance of soluble thrombomodulin in the coronary circulation of patients with coronary artery disease]

OBJECTIVES

The relationship between plasma levels of soluble thrombomodulin, a probable marker for endothelial damage, and the severity of coronary atherosclerosis was investigated.

METHODS

Plasma soluble thrombomodulin levels were evaluated in 160 patients(mean age 62 +/- 11 years) who underwent coronary angiography. Blood samples were obtained from the peripheral vein, ostium of the left coronary artery and coronary sinus. The levels of plasma thrombomodulin were measured by enzyme-linked immunosorbent assay. The change of thrombomodulin level in the coronary circulation (delta TM) was calculated as the coronary sino-arterial difference. Patients were classified into four groups according to the number of diseased vessels, and the severity of coronary atherosclerosis was evaluated with the modified Gensini score.

RESULTS

Coronary sinus levels of thrombomodulin were significantly higher in the two or more vessel disease(VD) groups than in the no or one VD groups(p < 0.05). delta TM were significantly higher in the 2VD than in the 0VD groups(p < 0.05), and higher in the 3VD than in the 0VD or 1VD groups(p < 0.05). delta TM showed positive correlation with Gensini score for left coronary arteries(r = 0.347, p < 0.0001).

CONCLUSIONS

The increment of thrombomodulin across the coronary circulation was significantly correlated with the severity of coronary atherosclerosis, suggesting a close association between the progression of coronary atherosclerotic stenosis and damage to the endothelial surface.

[Effect of percutaneous transvenous mitral commissurotomy for the preservation of sinus rhythm in patients with mitral stenosis]

OBJECTIVES

Atrial fibrillation is frequently associated with mitral stenosis and is considered to be an unfavorable factor for the long-term prognosis. The efficacy of percutaneous transvenous mitral commissurotomy(PTMC) was examined for the preservation of sinus rhythm in patients with mitral stenosis after PTMC.

METHODS

Long-term clinical data after PTMC were obtained from 71 patients who had undergone PTMC from March 1989 to September 1999. Eighteen patients in sinus rhythm before PTMC were divided into two groups: the SR group(n = 5) who remained in sinus rhythm, and the Af group(n = 13) who showed change from sinus rhythm to persistent or paroxysmal atrial fibrillation after PTMC.

RESULTS

Age, sex, mitral valve area(1.4 +/- 0.3 vs 1.2 +/- 0.3 cm2), mean mitral pressure gradient(14.3 +/- 5.5 vs 12.6 +/- 5.9 mmHg), mean left atrial pressure(15.9 +/- 7.6 vs 19.0 +/- 7.7 mmHg), left ventricular end-diastolic pressure(7.5 +/- 2.8 vs 9.3 +/- 3.9 mmHg), left ventricular end-diastolic volume index(77 +/- 13 vs 82 +/- 14 ml/m2), left ventricular ejection fraction(60 +/- 6% vs 55 +/- 4%) and cardiac output(5.1 +/- 0.4 vs 4.9 +/- 0.8 l/m2) before PTMC were not different between the two groups. Changes in mean mitral pressure gradient, mean left atrial pressure and cardiac output immediately after PTMC were not different statistically. Mitral valve area immediately after PTMC was significantly greater in the SR group compared to the Af group(2.3 +/- 0.3 vs 1.8 +/- 0.3 cm2, p < 0.05). The change in mitral valve area was also greater in the SR group(1.0 +/- 0.2 vs 0.6 +/- 0.4 cm2, p < 0.05), but there was no statistical difference in the percentage change of mitral valve area between before and immediately after PTMC(SR group 78 +/- 35% vs Af group 50 +/- 35%). End-diastolic pressure, end-diastolic volume index and ejection fraction immediately after PTMC were not statistically different.

CONCLUSIONS

The final mitral valve area immediately after PTMC in the patients with mitral stenosis in sinus rhythm, but not the changes of mean mitral pressure gradient, mean left atrial pressure or cardiac output, is important for the maintenance of sinus rhythm.

Different localization of SeqA-bound nascent DNA clusters and MukF-MukE-MukB complex in Escherichia coli cells

MukF, MukE and MukB proteins form a complex that may participate in the organization of folded sister chromosomes in Escherichia coli. We have found that a MukB-GFPuv4 fusion protein is observed as discrete fluorescent foci, which are localized within cellular spaces occupied by nucleoids, but not at the constriction site of cell division in living cells. In contrast, MukB-GFPuv4 is distributed throughout the whole cell when either MukF or MukE is absent. Statistical analysis revealed that most newborn cells have two foci of mukB-gfpUV4 at one-quarter and three-quarter positions in the cell length and one focus of SeqA-bound nascent DNA at or near the middle of the cell. Subsequently, the single SeqA focus divides into two foci, and then these migrate to the one-quarter and three-quarter positions. Before cell division, most long cells have two SeqA foci and four MukB-GFPuv4 foci. In early stationary phase, SeqA foci disappear, but one or two foci of MukB-GFPuv4 remain. We discuss the reorganization and proper arrangement of folded sister chromosome in the cell quarter positions, which are performed after release from the long-time cohesion of sister chromosomes.

Competition between the replication initiator DnaA and the sequestration factor SeqA for binding to the hemimethylated chromosomal origin of E. coli in vitro

BACKGROUND

Following replication initiation, the replication origin (oriC) in Escherichia coli enters a hemimethylated state at Dam methylation sites which are recognized by the SeqA protein. SeqA binds preferentially to hemimethylated GATC sequences of DNA in vitro. SeqA is essential for the synchronous initiation of chromosome replication from oriC copies in vivo.

RESULTS

We show that: (i) purified SeqA binds AT-rich and 13-mers regions and two DnaA boxes, R1 and M, of hemimethylated oriC. (ii) SeqA inhibits the in vitro replication of a hemimethylated oriC plasmid more efficiently than the fully methylated, (iii) SeqA inhibits competitive binding of DnaA protein to the regions of the hemimethylated oriC plasmid, explaining the mechanism of its inhibitory effect. The inhibition of DnaA binding by SeqA also occurs efficiently on a small hemimethylated oriC fragment containing both R1 and M DnaA boxes, but not the 13-mer region.

CONCLUSIONS

SeqA binds strongly the long region from the AT-rich region to the M DnaA box of the hemimethylated oriC DNA and releases DnaA molecules from the long region.

Null mutation of the dam or seqA gene suppresses temperature-sensitive lethality but not hypersensitivity to novobiocin of muk null mutants

Escherichia coli mukF, mukE, and mukB null mutants have common phenotypes such as temperature-dependent colony formation, anucleate cell production, chromosome cutting by septum closure, and abnormal localization of SeqA-DNA clusters. We show here that the associated muk null mutations cause hypersensitivity to novobiocin. Null mutation of either dam or seqA suppressed partially the temperature-sensitive lethality but failed to suppress the anucleate cell production and the hypersensitivity to novobiocin caused by muk null mutations.

Factors predicting mortality in patients after myocardial infarction caused by left main coronary artery occlusion: significance of ST segment elevation in both aVR and aVL leads

Acute left main coronary artery obstruction is rare and most patients in this clinical setting die of sudden death or cardiogenic shock. During the past 8 years, we encountered 13 patients with acute myocardial infarction caused by total occlusion of the left main coronary artery (LMCA-AMI). Thus, we surveyed these patients, and attempted to elucidate helpful predictors related to the prognosis. Six of 13 patients with LMCA-AMI survived. Successful left coronary artery dilatation was achieved in all survivors (group S), and in 5 (71%) non-survivors (group non-S). The age was not different between the two groups. A past history of angina was confirmed in 83% of group S. while only in 29% of group non-S. Clinical findings such as time of onset of AMI, interval from the AMI onset to admission, elapsed period from the AMI onset to recanalization of LMCA and the value of CK on admission were not different between the two groups. However, cardiogenic shock occurred in only 1 patient (17%) in group S compared with 5 patients (71%) in group non-S. As emphasized in the literature, good collateral circulation to the left anterior descending artery was observed in 5 patients (83%) in group S, while not observed in group non-S. Electro cardiographically, ST elevation in the aVR lead was very characteristic. This finding was confirmed in 69% of the total patients. Noticeably, 5 out of 6 non-survivors (83%) showed ST elevation not only in leads aVR but also in the aVL lead. In addition to the absence of collateral circulation, this electrocardiographic finding, which obviously indicates the presence of extensive myocardial ischemia in the diseased heart, is a simple and important predictor suggesting a poor prognosis in LMCA-AMI patients.

Decrease of nitric oxide end-products during coronary circulation reflects elevated basal coronary artery tone in patients with vasospastic angina

The aim of this study was to investigate the role of nitric oxide (NO) in the coronary circulation and its relation to basal coronary artery tone in patients with vasospastic angina (VSA). We evaluated the level of nitric oxide end-products (NOx; nitrite + nitrate) in coronary circulation blood using an HPLC-Griess system for nine patients with VSA and nine control patients. All of the patients with VSA experienced focal spasm in the proximal to middle segments of the left anterior descending coronary artery (LAD) in response to intracoronary injection of ergonovine maleate. The luminal diameter of the coronary artery was measured in each patient by quantitative coronary arteriography. Blood samples for NOx measurement were obtained from the coronary sinus (NOxV) and the ostium of the left coronary artery (NOxA). The NOx difference, calculated from the coronary venous-arterial difference in NOx, was close to zero for the control patients whereas it was clearly negative for the patients with VSA. In addition, the NOx difference in the patients with VSA showed a negative correlation with basal coronary artery tone (r = -0.91, p < 0.01) and a positive correlation with the dose of ergonovine required for spasm provocation (r = 0.77, p < 0.05). These results indicate that increased basal coronary artery tone and higher susceptibility to ergonovine in patients with VSA would be a consequence of coronary endothelial dysfunction as is indicated by NOx.

Hypertrophic cardiomyopathy with dominant hypertrophy in the right anterobasal region of the ventricular septum: a case report

A 62-year-old man was referred to our hospital for investigation of abnormal electrocardiography findings. The mean frontal plane QRS axis was directed toward the right superior quadrant(-125 degrees). Terminal S waves were present in all 3 bipolar standard leads and an R wave in lead aVR. RS complex was seen in lead V1 and deep S waves in leads V2-V6. Left ventricular hypertrophy associated with asymmetrical septal hypertrophy was suspected based on transthoracic echocardiography, but the echocardiographic quality was poor. Magnetic resonance imaging revealed hypertrophic cardiomyopathy with massive wall thickening involving the right anterobasal region of the ventricular septum. Magnetic resonance imaging may provide useful information about the distribution of ventricular myocardial hypertrophy in patients with hypertrophic cardiomyopathy and unusual electrocardiography findings.

Bidirectional migration of SeqA-bound hemimethylated DNA clusters and pairing of oriC copies in Escherichia coli

BACKGROUND

We previously found that SeqA protein, which binds preferentially to newly replicated hemimethylated DNA, is localized as discrete fluorescent foci in Escherichia coli cells. A single SeqA focus, localized at midcell, separates into two foci and these foci migrate abruptly in opposite directions.

RESULTS

The present study shows that (i) appearance of SeqA foci depends on continuous DNA replication, suggesting that the SeqA foci represent clusters consisting of SeqA and newly replicated hemimethylated DNA, (ii) in a synchronous round of replication, a single SeqA focus at midcell separates into two foci and these foci abruptly migrate in opposite directions midway through replication from oriC to the terminus, and (iii) oriC is replicated at midcell but replicated oriC copies remain linked with each other at midcell for 40 min after replication at 30 degrees C. Subsequently, the linked oriC copies separate and migrate gradually towards both borders of the nucleoid before cell division.

CONCLUSIONS

A single cluster of SeqA-bound hemimethylated DNA segment separates into two clusters and these clusters migrate abruptly in a bipolar fashion during progress of replication and prior to separation of linked sister oriC copies.

Negative NO3- difference in human coronary circulation with severe atherosclerotic stenosis

To examine whether or not the levels of NOx (nitrite; NO2- and nitrate; NO3-) in coronary circulating blood reflect endothelial dysfunction due to coronary atherosclerosis, NOx levels in plasma obtained from ostium of left coronary artery and coronary sinus of patients who complained of chest pain were evaluated in relation to their coronary angiographic findings. Prior to the study, a HPLC-Griess system for NOx measurement was critically evaluated. This system has a detection limit of 0.1 microM of NO2- and NO3- by 10 microl of loading and was able to distinguish a difference of 0.1-0.2 microM of these substances. Heparin (1 U/10 microl) did not affect the detective and discriminative abilities. NO3- difference, calculated from sino-arterial difference of NO3-, was almost zero (-0.2 +/- 0.2 microM) in patients with either normal coronary arteries or mild organic coronary stenosis (< or = 20% narrowing), while a significant negative value (-5.9 +/- 1.7 microM) was obtained from patients with significant stenosis (> or = 70% narrowing) in the left coronary arteries. These results demonstrate reliable ability on the HPLC-Griess system in evaluating NO2- and NO3- in biological samples, and that the negative NO3- difference through coronary circulation may reflect endothelial dysfunction in the patients with coronary atherosclerosis with severe organic stenosis.

[Atresia of the right atrial orifice of the coronary sinus with persistent left superior vena cava: a case report]

A 39-year-old woman presented with atresia of the right atrial orifice of the coronary sinus with a persistent left superior vena cava detected at cardiac catheterization. She was admitted with frequent episodes of angina at rest and on exertion. Coronary angiography, including spasm provocation test, yielded normal results. However, left coronary arteriography demonstrated a dilated coronary sinus and a persistent left superior vena cava draining into the innominate vein. The contrast medium leaked slightly into the right atrial cavity through the obstructed orifice of the coronary sinus. Atresia of the coronary sinus orifice is a rare malformation usually found at autopsy. Only 3 cases have been reported in Japan. This is the first adult Japanese case detected when the patient was still alive.

Complex formation of MukB, MukE and MukF proteins involved in chromosome partitioning in Escherichia coli

mukF, mukE and mukB genes are essential for the process of chromosome partitioning in Escherichia coli. We have studied protein-protein interactions among MukB, MukE and MukF proteins by co-immunoprecipitation and sucrose gradient sedimentation experiments, using mukFEB null cells harboring plasmids carrying the wild-type or mutant-type mukFEB operon. MukB forms a complex with MukF and MukE. Analysis of mutant MukB proteins suggested that MukF and MukE bind the C-terminal globular domain of MukB. MukF is indispensable for an interaction between MukB and MukE; however, MukF itself is able to associate with MukB even in the absence of MukE. We have also found that MukF has a Ca(2+)-binding activity. Although purified MukF was able to make a complex either with MukE or MukB, a complex consisting of the three Muk proteins was barely detected in vitro. However, increasing the Ca(2+) or Mg(2+) concentration in the reaction partially restored complex formation. This suggests that Ca(2+) or Mg(2+) may be required for the formation of a complex consisting of the three Muk proteins, and thus may participate in a particular step during chromosome partitioning.

Life span of Japanese male medical doctors

There have been few reports with regard to the life spans of medical doctors. The status of the medical doctors graduating from 1926 to 1974, alive or dead as of October 1996, was ascertained on the basis of the list of graduates from the School of Medicine, Hokkaido University. Excluding data on female doctors and those who died in battle during World War II, data on a total of 3,982 doctors were available for study. Their mortality as of October 1996 decreased in parallel with the graduation year. Their mean future life span at graduation was estimated to be about 52.88 years (95% CI, 52.45-53.31) through linear regression (r = 0.992). Their mean age at graduation was 25.17 years. This was not different from the future life expectancy at 25 years of age of the general population (52.35 years). The future life span of surgeons and gynecologists-obstetricians was shorter than that of the doctors of basic medical sciences and internal medicine. This difference might be accounted for by factors peculiar to each speciality (e.g., exposure to blood) or by the degree of stress from work.

The assembly and migration of SeqA-Gfp fusion in living cells of Escherichia coli

SeqA protein, which binds to hemi-methylated GATC sequences of DNA, is localized to discrete fluorescent foci in wild-type Escherichia coli cells. In this work, we observed cellular localization of the SeqA-Gfp fusion in living cells. SeqA-Gfp was localized to a discrete focus or foci in wild-type and seqA null mutant cells, but the fusion was dispersed in the whole cell in dam null mutant cells lacking Dam methyltransferase. These results were consistent with the previous description of the localization of SeqA by immunofluorescence microscopy. Time-lapse experiments revealed that duplicated SeqA-Gfp foci migrated rapidly in opposite directions. Flow cytometry demonstrated that the fusion restored synchronous replication of chromosomal DNA from multiple origins in seqA null mutant cells, indicating that SeqA-Gfp is biologically active. Immunoprecipitation of the fusion from cell extracts using anti-Gfp antibody indicated that the fusion was assembled with the wild-type SeqA protein.

Progression to moderate or severe mitral regurgitation after percutaneous transvenous mitral commissurotomy using stepwise inflation technique

Progression to moderate or severe mitral regurgitation (MR) was studied after Inoue balloon percutaneous transvenous mitral commissurotomy (PTMC) using the stepwise inflation technique, performed at increments of 1 mm of balloon diameter, in 49 consecutive patients with rheumatic mitral stenosis (aged from 32-73 years; 8 males, 41 females). The patients were classified on the basis of the degree of MR after PTMC, compared with that before PTMC, into either Group A, development of moderate or more severe (> or = grade 2) MR (n = 8) or Group B, no increase in MR or development of mild (grade 1) MR (n = 41). Progression to moderate or severe MR was significantly associated only with advanced age (60 +/- 8 vs 52 +/- 10 years, p < 0.05) and narrower mitral valve area (0.87 +/- 0.35 vs 1.11 +/- 0.29 cm2, p < 0.05), but other characteristics before PTMC were similar in both groups. There was no difference between the two groups in the total number and degree of balloon inflation. Immediately before the final inflation, the left atrial mean pressure and v wave pressure were decreased in smaller degrees in Group A compared with Group B (-2 +/- 2 vs -5 +/- 4 mmHg, p < 0.05; -2 +/- 2 vs -6 +/- 6 mmHg, p < 0.05, respectively). Thus, the stepwise inflations require careful monitoring of changes in the left atrial pressure and waveform to recognize the aggravation of MR, especially in older patients with severe stenosis. Patients who do not have a significant drop in left atrial mean pressure and v wave pressure during stepwise inflations of the balloon might be at risk of development of moderate or severe MR after further dilations.

Cell cycle-dependent duplication and bidirectional migration of SeqA-associated DNA-protein complexes in E. coli

Using immunofluorescence microscopy, we have found that SeqA protein, a regulator of replication initiation, is localized as discrete fluorescent foci in E. coli wild-type cells. Surprisingly, SeqA foci were observed also in an oriC deletion mutant. Statistical analysis revealed that a SeqA focus is localized at midcell in newborn cells. The SeqA focus is duplicated and tethered at midcell until an FtsZ ring is formed. Subsequently, these foci migrate in opposite directions toward cell quarter sites and remain tethered there until the cell divides. The cell cycle-dependent bidirectional migration of SeqA-DNA complexes is quite different from the migration pattern of oriC Dna copies. MukB protein is required for correct localization of SeqA complexes by an unknown mechanism.

Autoregulation of the partition genes of the mini-F plasmid and the intracellular localization of their products in Escherichia coli

The sopAB operon and the sopC sequence, which acts as a centromere, are essential for stable maintenance of the mini-F plasmid. Immunoprecipitation experiments with purified SopA and SopB proteins have demonstrated that these proteins interact in vitro. Expression studies using the lacZ gene as a reporter revealed that the sopAB operon is repressed by the cooperative action of SopA and SopB. Using immunofluorescence microscopy, we found discrete fluorescent foci of SopA and SopB in cells that produce both SopA and SopB in the presence of the sopC DNA segment, but not in the absence of sopC, suggesting the SopA-SopB complex binds to sopC segments. SopA was exclusively found to colocalize with nucleoids in cells that produced only SopA, while, in the absence of SopA, SopB was distributed in the cytosolic spaces.

Correlation between arteriographic and electrocardiographic features during spasm in the left anterior descending coronary artery

BACKGROUND

The clinical role of collateral vessels, which are transiently augmented during coronary artery spasm, remains controversial.

OBJECTIVE

To examine the correlation between coronary arteriographic and electrocardiographic features during spasm in the left anterior descending artery (LAD).

METHODS

We studied 45 patients in whom LAD spasms were induced by administration of acetylcholine or ergonovine maleate into the left coronary artery, or in whom spontaneous LAD spasms were documented during diagnostic cardiac catheterization.

RESULTS

During spasm, only three patients had transient appearance or augmentation of collateral flow opacifying the LAD. In these three patients, electrocardiograms obtained from anterior precordial chest leads during LAD spasm showed ST-segment depression, ST-segment elevation followed by ST-segment depression, and only T-wave change, respectively. Except for these three patients, ST-segment elevations were observed in all other patients (31 of 34) with main-branch spasm of the LAD. However, ST-segment elevation was observed in only two of 11 patients in whom spasm of the diagonal branch alone was induced.

CONCLUSIONS

Our observations suggest that the electrocardiographic changes during spasm are not always a sensitive indicator of LAD side branch spasm or LAD main-branch spasm associated with collateral circulation. From consideration of the angiographic features of the collaterals in the three patients with LAD main-branch spasm, we speculate that the balance of tonus of both the recipient and donor arteries, and the degree of organic stenosis of the recipient artery, may have important roles in the mechanism responsible for the change in the appearance of collaterals in patients with coronary spasm.

Coronary artery perforation with subepicardial hematoma

Coronary artery perforation is a relatively rare complication in coronary angioplasty. We report the case of a 71-year-old male, who was salvaged by emergency surgery, for cardiogenic shock due to subepicardial hematoma associated with balloon angioplasty. Such a case has not yet previously been reported.

Increasing vasoconstrictor response to ergonovine with oxidative injury in canine coronary artery

BACKGROUND

The effects of oxygen free radicals on coronary vasoreactivity remain unknown.

OBJECTIVE

To examine whether oxygen free radicals increase coronary arterial tone and sensitivity to vasoconstrictor stimulation in closed-chest dogs.

METHODS

Oxygen radicals were generated by the reaction of xanthine plus xanthine oxidase (XXO) and effects of these substances on the left coronary artery (the percentage diameter change) and on the constrictor effect of ergonovine were examined in vivo in 19 anesthetized, closed-chest dogs by selective coronary angiography. The effects of XXO solution and ergonovine were assessed in a cumulative fashion using 100, 200, and 300 ml XXO and 50, 100, 150, and 200 micrograms ergonovine, in 5 (group I) and 6 dogs (group II), respectively. The effects of XXO on the constrictor responses elicited by 50 micrograms ergonovine were examined in eight dogs (group III). Changes in the vascular endothelium were examined by postmortem electron microscopic examination.

RESULTS

Oxidative injury alone produced slight constriction of the coronary artery, but the change was not significant. However, ergonovine-induced vasoconstriction was enhanced after administration of 100 and 200 ml (cumulative amount) XXO solution (P < 0.05, group II versus group III). The enhancement was no longer observed after administration of 300 ml (cumulative amount) XXO solution. Scanning and transmission electron microscopies revealed the formation of blebs and ulceration in the coronary endothelium after administration of XXO solution.

CONCLUSION

These results suggest that oxygen radicals can enhance the ergonovine-induced coronary vasoconstriction in a concentration-dependent manner. There seems to be a critical level of oxygen radicals for the production of the effect.

Carboxyl terminal region of the MukB protein in Escherichia coli is essential for DNA binding activity

The purified MukB protein of Escherichia coli has DNA binding activity and nucleotide binding activity. We have isolated a mutation, mukB1013, causing a substitution of valine at position 1379 to leucine. This mutant MukB protein was defective for DNA binding, while the ATP binding activity remained unaffected. A truncated MukB protein that is short of 109 amino acids from the C-terminus failed to bind DNA.

Gene therapy for malignant gliomas using replication incompetent retroviral and adenoviral vectors encoding the cytochrome P450 2B1 gene together with cyclophosphamide

Cyclophosphamide is an inactive prodrug which is converted by hepatic cytochrome P450 2B1 to cytotoxic metabolites which produce interstrand DNA cross-linking in a cell cycle-independent fashion. The limited ability of these metabolites to cross the blood-brain barrier contributes to the poor activity of cyclophosphamide against brain tumors. In this study we demonstrate that replication deficient retroviral and adenoviral vector-mediated gene transfer of cytochrome P450 2B1 into 9L glioma cells significantly increases the sensitivity of these tumor cells to cyclophosphamide in vitro, and prolongs the survival of animals bearing intracerebral 9L tumors treated with cyclophosphamide in vivo. Attempts to improve the effectiveness of retrovirally mediated transduction of the P450 2B1 gene by increasing the concentration of cyclophosphamide delivered to the tumors using intracarotid and intratumoral injections did not prolong animal survival, although survival was increased when a second treatment with P450-expressing retroviral vectors and cyclophosphamide was administered. These results suggest that in situ transduction of tumor cells with the P450 2B1 gene using retroviral and adenoviral vectors increases their sensitivity to cyclophosphamide and may have a potential role in the therapy of malignant gliomas.

Suppression of fluid accumulation following pericardial inflammation in a patient with primary chylopericardium

The patient was a 50-year-old woman with primary chylopericardium. Triglyceride rich chyloid fluid was continuously drained from the pericardial space through an indwelling catheter. A surgical procedure was scheduled since a medium chain triglyceride diet was insufficient to control the fluid accumulation. Before the operation, inflammatory signs were apparent around the indwelling catheter and the catheter was removed immediately. The inflammation was easily treated with antibiotics, and the pericardial effusion no longer accumulated during a follow-up period of 10 months. The inflammatory process may have caused fibrin production and tissue adhesion in the pericardial cavity, and these might have prevented an accumulation of chyloid fluid and occluded the connection between the thoracic duct and the pericardial cavity.

[Circularity index of left ventricular shape in the assessment of heart disease]

Left ventricular volume and ejection fraction obtained by cineangiography are useful to evaluate global left ventricular function in humans. Left ventriculography provides evidence of the effect of coronary artery stenosis on regional wall motion in patients with coronary artery disease. Changes in left ventricular shape are also found in various heart diseases. The left ventricular cavity is normally ellipsoid in shape, but becomes flat in hypertrophic cardiomyopathy, globular in dilated cardiomyopathy, and aneurysmal in some patients with myocardial infarction. This study developed a new method to quantify regional and global left ventricular shape. Regional circularity index (RCI) was defined as GD divided by r (GD = distance from each 5-degree endocardial margin to the center of gravity, r = radius of the circle equal to left ventricular area). The global circularity index (GCI) was derived from the sum of magnitude of RCI-1. The end-systolic GCI was related to end-systolic left ventricular wall stress (r = 0.71, p < 0.001). The change in GCI during systole was related to left ventricular ejection fraction (r = 0.79, p < 0.001). In severe cases of dilated cardiomyopathy, the left ventricle became more spherical during ejection. End-systolic left ventricular moment around the minor axis had a good correlation with left ventricular ejection fraction (r = 0.81, p < 0.001). Quantification of regional and global left ventricular shape can be used to estimate left ventricular wall stress from left ventricular shape. Left ventricular shape change during systole and the moment around the left ventricular short axis contributes to left ventricular ejection.

Correlation between isolated negative U waves and the grade of coronary artery spasm

The relation between isolated negative U waves and the severity of induced coronary artery spasm was investigated in 24 patients with variant angina to determine the grade of myocardial ischemia during the appearance of isolated negative U waves. Coronary artery spasm was induced by injections of either incremental doses of acetylcholine or ergonovine into the left coronary artery. Coronary spasm was quantified into 4 grades: Grade 0 = complete perfusion, Grade 1 = partial perfusion, Grade 2 = penetration without perfusion, and Grade 3 = no perfusion. Induction with acetylcholine was discontinued when a coronary spasm of Grade > or = 2 was induced. Electrocardiogram in leads V1 to V6 and systemic blood pressure were recorded continuously. Provocations of coronary spasm with at least 2 doses of acetylcholine could be performed in 15 patients. All acetylcholine-induced coronary spasms of Grade < or = 1 disappeared spontaneously within 3 min. Negative U waves developed in 19 (79%) patients, in whom 37 trials with acetylcholine or ergonovine injection were performed. Isolated negative U waves were detected in 10 trials, negative U waves and ST depression in 8 trials, and negative U waves and ST elevation in 14 trials. The induced coronary spasms associated with isolated negative U waves were of Grade 1 in 9 of the 10 trials. In contrast, all of the coronary spasms associated with negative U waves and ST elevation had a Grade of > or = 2. In conclusion, the coronary angiographic finding associated with isolated negative U waves is coronary spasm with delayed filling of the distal coronary artery, with opacification of the entire coronary bed.

Angina-linked syncope and lack of calcium antagonist therapy predict cardiac arrest before definitive diagnosis of vasospastic angina

BACKGROUND

Several prognostic factors have been identified in patients with vasospastic angina; however, factors that would predict potentially fatal cardiac arrest during the period between the onset of angina and its definitive diagnosis remain unknown. We investigated the predictive value of the clinical findings that are available when a patient is hospitalized after a cardiac arrest but before a definitive diagnosis of vasospastic angina is made.

METHODS

We compared the clinical findings in 11 patients who experienced cardiac arrest before vasospastic angina was definitively diagnosed (group I) with 81 patients with vasospastic angina without cardiac arrest (group II). The definitive diagnosis of vasospastic angina was made on the basis of results of coronary spasm provocation test or ECGs during spontaneous attacks, or both.

RESULTS

The incidence of angina-linked syncope was significantly higher in group I than in group II (six out of 11 versus nine out of 81, P < 0.005). Significantly fewer group I patients were receiving calcium antagonists than group II patients (three out of 11 versus 63 out of 81, P < 0.005). Serious arrhythmias were significantly more common in group 1 than in group II (seven out of 11 versus 12 out of 81, P < 0.005). Logistic regression analysis of the eight clinical variables available when first seen in the hospital indicated that angina-linked syncope and the lack of calcium antagonist therapy were independently related to risk of cardiac arrest.

CONCLUSIONS

From the clinical findings available, a history of angina-linked syncope and lack of calcium antagonist therapy were found to be independent predictors of cardiac arrest before a definitive diagnosis had been made. Patients who have suspected vasospastic angina may benefit from early treatment with calcium antagonists if they have a history of angina-linked syncope.

Clinical and angiographic characteristics of patients with multivessel coronary spasm in variant angina. Significance of progressive course of angina and disease activity

The purpose of this study was to investigate the incidence of multivessel coronary spasm and compare the clinical characteristics between patients with and without multivessel coronary spasm. In variant angina, it is controversial whether coronary hyperreactivity to vasoconstrictor stimuli is localized to a segmental lesion in only one coronary artery. Moreover, the clinical characteristics of patients with multivessel coronary spasm have never been investigated. Sixty-three patients (51 men and 12 women; mean age, 56 years; range 35-72 years) with variant angina and documented ST-segment elevation during a spontaneous attack underwent spasm provocation testing with selective intracoronary injection of ergonovine. All but 4 patients who experienced spontaneous attacks during cardiac catheterization had induced coronary spasm associated with ST-segment elevation and chest pain. Multivessel coronary spasm was found in 27 (43%) of 63 patients. By univariate analysis, a high frequency of angina (> or = 3 times/week), occurrence of a spontaneous attack within 24 hours after withdrawal of medication, a long history of angina and a progressive course of angina were significantly associated with multivessel coronary spasm. Multivariate analysis indicated a positive correlation between multivessel coronary spasm and progressive angina. Multivessel coronary spasm was found in 43% of patients with variant angina. Patients with multivessel coronary spasm have some unique clinical features. These results may increase the understanding of the pathophysiology and natural course of variant angina.

A protein which binds preferentially to single-stranded core sequence of autonomously replicating sequence is essential for respiratory function in mitochondrial of Saccharomyces cerevisiae

From yeast nuclear extract, we have identified several DNA-protein complexes using the T-rich strand of core consensus sequence of autonomously replicating sequence by gel shift assay. One of them showed preferential binding to the T-rich sequence of the DNA. We have partially purified a protein constituent of this complex and cloned its gene. The gene has an open reading frame encoding a protein of 380 amino acids (M(r) = 42,100) which is processed to a mature protein of 371 amino acids (M(r) = 40,900). The protein has neither significant amino acid homology with any previously reported proteins nor characteristic motifs. A putative HAP2/HAP3/HAP4 binding sequence was found at about 1 kilobase upstream of the gene. Disruption of the chromosomal gene revealed that the gene was neither essential for cell viability nor involved in DNA replication, but was essential for mitochondrial respiratory function. We therefore named the gene MRF1 for mitochondrial respiratory function 1. In a mrf1 null mutant the absorption spectra of cytochromes b, a, and a3 were undetectable, although mitochondrial DNA and protein synthesis in mitochondria were intact. Antibodies against MRF1 detected the antigen localized predominantly in the nucleus in vivo. These results suggest that MRF1 is a transcriptional regulatory protein of some genes whose products are necessary for the functional assembly of mitochondrial respiratory proteins.

Acute effect of percutaneous transvenous mitral commissurotomy on ventilatory and hemodynamic responses to exercise. Pathophysiological basis for early symptomatic improvement

BACKGROUND

Improvement of exertional dyspnea occurs immediately after percutaneous transvenous mitral commissurotomy (PTMC), but the pathophysiological basis for this early symptomatic improvement has not been elucidated.

METHODS AND RESULTS

Exercise hemodynamic measurement and exercise ventilatory measurement with arterial blood gas analysis were performed in 21 patients aged 50.4 +/- 9.5 years (mean +/- SD) with symptomatic mitral stenosis before and a few days after PTMC. Exercise ventilatory measurement were also performed in 14 normal control subjects aged 48.9 +/- 4.9 years. After PTMC, mitral valve area increased (from 1.0 +/- 0.3 to 1.7 +/- 0.3 cm2, P < .001), mean mitral gradient (from 12.2 +/- 5.2 to 5.2 +/- 2.2 mm Hg, P < .001), and mean left atrial pressure (from 18.7 +/- 6.1 to 12.1 +/- 4.0 mm Hg, P < .001) decreased. All patients experienced significant symptomatic improvement soon after PTMC. Comparison of hemodynamic parameters at the same ergometer work rate showed a significant decrease in pulmonary artery systolic pressure (from 77 +/- 18 to 67 +/- 14 mm Hg, P < .001) and diastolic pressure (from 36 +/- 10 to 28 +/- 7 mm Hg, P < .001) and a significant increase in cardiac output (from 6.4 +/- 1.4 to 8.1 +/- 1.9 L/min, P < .001). Despite the improvement in exercise hemodynamics and symptoms, exercise capacity determined by peak oxygen uptake (from 18.0 +/- 2.9 to 18.6 +/- 3.1 mL.kg-1 x min-1) and anaerobic threshold (from 11.7 +/- 2.4 to 12.0 +/- 2.4 mL.kg-1 x min-1) remained unchanged. Excessive exercise ventilation, as assessed by the slope of the regression line between expired minute ventilation and carbon dioxide output, decreased significantly from 37.2 +/- 6.7 to 33.9 +/- 5.8 (P < .001), but remained significantly higher than that in the normal subjects (27.9 +/- 3.6, P < .01). The ratio of total dead space to tidal volume and total dead space per breath during exercise decreased significantly after PTMC (P < .05). The change in excessive exercise ventilation after PTMC was correlated with the change in dead space to tidal volume ratio (r = .59).

CONCLUSIONS

Significant relief of exertional dyspnea immediately after PTMC is not accompanied by an improvement in exercise capacity. A decrease in excessive ventilation due to a decrease in physiological dead space resulting from hemodynamic improvement partly contributes to the early relief of symptoms after PTMC. However, lung compliance, which was not measured in the present study, may have changed after PTMC. This change may also contribute to the symptomatic improvement.

[A case of dual origin of the left anterior descending coronary artery from the left and right coronary arteries with variant angina]

We present a case of a 68-year-old male inflicted with a rare anomaly of the coronary artery. He had been suspected to have worsening effort angina and underwent urgent cardiac catheterization. The coronary angiography revealed 75% stenosis in the first diagonal branch. The left anterior descending artery was terminated in the mid portion and did not reach the apex. Instead, an anomalous coronary artery from the portion just proximal to the right coronary artery reached the apex. After cardiac catheterization, nocturnal chest pain at rest started to occur frequently. We suspected that vasospasm may have occurred because ST segment elevations in leads II, III, aVF were recorded on the electrocardiogram. Administration of diltiazem (120 mg per day) suppressed angina. Exercise stress electrocardiogram and thallium-201 myocardial scintigram did not show apparent ischemia. This case suggests that we must consider the presence of coronary vasospasm even in patients with clinically-supposed effort angina, to be possibly due to vasospasm occurring in anomalous coronary arteries.

Coronary artery spasm is a major cause of sudden cardiac arrest in survivors without underlying heart disease

BACKGROUND

The role of coronary spasm in underlying disease-free patients who were resuscitated from sudden cardiac arrest remained uncertain. This study investigated the cause of cardiac arrest, and the etiologic and prognostic differences were compared between patients with underlying heart disease (group I) and those patients without underlying heart disease (group II).

METHODS

Twenty-five survivors of sudden cardiac arrest were classified into two groups according to the presence or absence of underlying heart disease. To investigate the cause of cardiac arrest, we performed ergonovine testing and electrophysiologic study. Fifteen of the patients had underlying heart disease, while 10 did not.

RESULTS

Electrophysiologic abnormalities were found in 13 of the 15 patients in group I. In group II, spontaneous attack of coronary spasm occurred in four patients during the observation period, and coronary spasm was induced in three of the remaining six period of 32 +/- 23 months, whereas no patients in group II had recurrence of sudden cardiac arrest at a median follow-up of 32 months (range, 10 to 72 months).

CONCLUSIONS

Electrophysiologic study identified a potential cause in 13 of 15 patients with underlying heart disease. Coronary spasm was involved in the pathogenesis of sudden cardiac arrest in survivors without identifiable underlying heart disease.

Balloon catheter with check valves for experimental relief of acute aortic regurgitation

To evaluate the ability of a newly designed balloon catheter with check valves to temporarily relieve hemodynamic deterioration in acute aortic regurgitation, we produced an experimental model of acute aortic regurgitation in closed-chest dogs using endomyocardial biopsy forceps. Aortic regurgitation was produced until an increase in aortic pulse pressure of over 50% was achieved. Left ventricular end-diastolic pressure rapidly increased after the production of aortic regurgitation. Immediately after the catheter began functioning, pulse pressure decreased from 133 +/- 1 to 78 +/- 5 mm Hg (mean +/- SEM) and left ventricular end-diastolic pressure also decreased from 26 +/- 1 to 13 +/- 1 mm Hg. These effects lasted as long as the catheter functioned. Although a mild (21 +/- 8 mm Hg) pressure gradient between the left ventricular peak systolic pressure and the aortic peak systolic pressure was observed when this catheter was used, forward stroke volume was no less than in the group in which the catheter had not been used. These findings suggest that the balloon catheter with check valves may effectively reduce aortic regurgitation.

A case of vasovagal syncope with convulsions--the effects of midodrine hydrochloride

A 42-year-old female had suffered from repeated syncope. She had vasovagal syncope with convulsions from vasodilatation and cardiac standstill which lasted for 9.8 sec. The 60 degrees head-up tilt test, nitroglycerin injection and isoproterenol infusion provoked vasovagal reaction. Although a beta blocker was not effective in preventing tilt-induced hypotension and bradycardia, midodrine hydrochloride (alpha-1 stimulant) or atropine prevented it. In this patient, insufficient constriction of capacitance vessels might have played an important role in activation of an inhibitory reflex from cardiopulmonary mechanoreceptors which caused hypotension and bradycardia.

High prevalence of coronary artery spasm in survivors of cardiac arrest with no apparent heart disease

The pathogenesis of cardiac arrest in the absence of any apparent heart disease remains unclear. Based on the hypothesis that coronary spasm may be a cause of cardiac arrest in the absence of apparent heart disease, ergonovine testing and/or electrophysiologic studies (EPS) were performed to evaluate the cause of cardiac arrest. Fourteen patients resuscitated from cardiac arrest had no apparent heart disease. A spontaneous episode of angina with ST-segment elevation occurred in 4 patients while under observation. Ergonovine testing was performed in 9 patients, and coronary spasm was induced in 5. EPS were performed in 8 patients, including 3 patients with coronary spasm. No electrophysiologic abnormalities were found in the 3 patients with coronary spasm. Ventricular fibrillation was induced by programmed ventricular stimulation in 2 patients with documented ventricular fibrillation at the time of resuscitation. All but one of the patients with coronary spasm had chest pain preceding cardiac arrest or at least a history of chest pain at rest, while 4 of 5 patients without coronary spasm had no prodromal symptoms. Patients with coronary spasm had a good prognosis when treated with a Ca-antagonist and/or long-acting nitrate. In conclusion, coronary spasm is the most frequent cause of cardiac arrest in cardiac arrest survivors with no apparent heart disease. Ergonovine testing should be performed to evaluate the cause of cardiac arrest when patients have no apparent heart disease.

Immediate effects of percutaneous transvenous mitral commissurotomy on pulmonary hemodynamics at rest and during exercise in mitral stenosis

Hemodynamics were evaluated during exercise in 33 patients with mitral stenosis who underwent percutaneous transvenous mitral commissurotomy (PTMC). PTMC was performed using an Inoue balloon. Each patient underwent a supine ergometer exercise test before and on the day after PTMC. Ergometer work load was started at 20 W and increased in increments of 20 W at 3-minute intervals until terminated by the patient's fatigue or shortness of breath. Mitral valve area increased by 0.8 +/- 0.4 cm2 (1.1 +/- 0.3 to 1.9 +/- 0.4 cm2, p less than 0.001). Mean mitral pressure gradient decreased (12 +/- 5 to 6 +/- 2 mm Hg, p less than 0.001). Pulmonary arterial pressure significantly decreased and the cardiac index significantly increased both at rest and during exercise after PTMC. Before PTMC, the increases in pulmonary arterial pressure, total pulmonary resistance and pulmonary arteriolar resistance during exercise were greater in patients with a mitral valve area less than 1.0 cm2 than in patients with an area greater than or equal to 1.0 cm2. After PTMC, total pulmonary resistance still increased during exercise. However, pulmonary arteriolar resistance did not change during exercise in patients with a mitral valve area greater than or equal to 1.5 cm2, whereas it increased in patients with an area less than 1.5 cm2. An enlarged mitral valve area greater than or equal to 1.5 cm2, which may prevent pulmonary vasoconstriction and permits a greater increase in pulmonary blood flow during exercise, is considered a good result immediately after PTMC.

Importance of coronary artery spasm in alcohol-related unexplained syncope

To examine the role of coronary artery spasm in patients with syncope after alcohol ingestion, we performed an intracoronary ergonovine provocation test in 7 male patients (39 to 73 years old, mean 54 years) with alcohol-related syncope which remained unexplained despite noninvasive cardiovascular and neurological examinations. No patients had structural heart disease or significant coronary artery stenosis. Ergonovine was continuously infused into each coronary artery at a rate of 10 micrograms/min for up to 5 min. Coronary artery spasm with ST-segment elevation was induced in 4 of 7 patients. Chest pain before syncope or history of chest pain were not present in 3 of 4 patients with a positive ergonovine test. Multivessel coronary artery spasm was induced in 3 patients. One patient presented with triple vessel coronary artery spasm progressing to near syncope as a result of profound hypotension and ventricular tachycardia during provocation. Coronary artery spasm was promptly relieved by intracoronary isosorbide dinitrate infusion. All patients with a positive ergonovine test were treated with calcium antagonist and did not experience syncope during follow-up. These results suggest that coronary artery spasm is one of the important causes of syncope after alcohol ingestion.

Effects of lidocaine on ischemic myocardial metabolism assessed by 31P-NMR in the isolated perfused rat heart

Using an isolated perfused rat heart preparation, the protective effects of lidocaine and diltiazem on ischemic derangements of myocardial energy metabolism were studied with 31P-nuclear magnetic resonance spectroscopy. The hearts were perfused with a solution containing lidocaine (4.27 x 10(-5), 12.80 x 10(-5) M) or diltiazem (2.22 x 10(-7), 2.22 x 10(-6) M) for 15 min prior to the induction of global ischemia. The decrease in myocardial oxygen consumption rate, assessed as the product of heart rate and left ventricular systolic pressure (HR x LVP), was greater in diltiazem-treated than in lidocaine-treated hearts. Diltiazem and lidocaine significantly retarded the fall in myocardial pH during ischemia and improved ATP recovery after reperfusion. There was a good correlation between suppression of HR x LVP observed before induction of ischemia and decreased drop in pH during the early phase of ischemia in the diltiazem-treated groups (r = -0.78, p less than 0.01), but not in the lidocaine-treated groups. These results indicate that the beneficial effects of diltiazem on the ischemic myocardium are due primarily to the cardio-depressant effects. The beneficial effects of lidocaine cannot, however, be explained solely on the basis of the depression of oxygen consumption.

Integration of woodchuck hepatitis virus (WHV) DNA at two chromosomal sites (Vk and gag-like) in a hepatocellular carcinoma

Integration of woodchuck hepatitis virus (WHV) DNA into the liver DNA of a woodchuck infected by the virus was investigated. Clonal viral integration was not detected three months before the appearance of four hepatocellular carcinomas (HCC). Integration of the viral DNA was detected in all four HCCs, of which one was chosen to determine the structure of the viral integration completely in a single tumor. The integration occurred in two sites. One part contains the viral DNA from the middle of the gene encoding surface antigen to two-thirds of the way through the gene encoding X protein (X) with no structural changes. The coding frame of the truncated X gene continues into the chromosomal sequence to make a possible fusion protein. The integration seems to have occurred by recombination within two direct repeats of the viral genome in one junction and by homologous recombination between viral DNA and chromosomal DNA in the other junction. The viral DNA is integrated into a spacer of the immunoglobulin L-chain Vk (IgVk) region without any chromosomal rearrangement accompanying the integration. The viral DNA at the second site has a complex structural rearrangement: part of the preS gene is duplicated and attached to the terminus of the gene encoding core antigen in a head-to-tail fashion, followed by three small fragments derived from other parts of the viral DNA. The integrated preS gene has its own 5' regulatory element and a coding frame consisting of the truncated preS gene, the other parts of viral DNA and the chromosomal sequence.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of direct intracoronary administration of methylergonovine in patients with and without variant angina

The effects of intracoronary administration of methylergonovine were studied in 21 patients with variant angina and 22 patients with atypical chest pain and in others without angina pectoris (control group). Methylergonovine was administered continuously at a rate of 10 micrograms/min up to 50 micrograms. In all patients with variant angina, coronary spasm was provoked at a mean dose of 28 +/- 13 micrograms (mean +/- SD). In the control group neither ischemic ST change nor localized spasm occurred. The basal tone of the right coronary artery was significantly lower than that of the left coronary artery. The percentage of vasoconstriction of the right coronary artery was significantly higher than that of the left coronary artery. These results suggest that spasm provocation tests, which use an intracoronary injection of a relatively low dose of methylergonovine, have a high sensitivity in variant angina and the vasoreactivity of the right coronary artery may be greater than that of the other coronary arteries.

Aortitis syndrome, coronary artery ectasia, and mid-ventricular obstruction

A 46-year-old Japanese woman, who had been diagnosed as having aortitis syndrome 4 years earlier, was admitted to our hospital in May 1989. The diagnosis of aortitis syndrome was confirmed by intravenous digital subtraction angiography which showed stenotic lesions in each subclavian artery, the left common carotid artery, and the descending aorta. Coronary arteriography revealed diffuse and prominent dilatation of entire coronary artery segments. Moreover, a left ventriculogram showed complete obstruction of the mid-ventricle during systole. Thus, we diagnosed this case as aortitis syndrome complicated by coronary artery ectasia and mid-ventricular obstruction. The causal relations of these findings are discussed.

Clinical characteristics and possible role of coronary artery spasm in syncope and/or aborted sudden death

We investigated the clinical and pathophysiologic characteristics in patients with vasospastic angina who developed syncope and/or experienced aborted sudden death (SD). Vasospastic angina was diagnosed using the methylergonovine test. Syncope was found in 32 (10.4%) patients among 309 who were admitted to our institute in a one-year period. The most frequent cause of syncope was ventricular tachycardia which was found in 10 (31.2%) of the 32 patients. The next important cause of syncope was vasospastic angina which was found in 7 patients (21.8%). Among the 7 patients with vasospastic angina who experienced one or more syncopal episodes, there were 3 patients with aborted SD, 3 with syncope and one with shock. Cardiovascular collapse was observed in 4. Interior wall ischemia was found in 5 and anterior wall ischemia in 2 during the methylergonovine test. None of the 7 patients had significant coronary stenosis. Two patients had no prodromal symptom such as chest pain. Our results suggest that coronary artery spasm may be one of the most frequent cardiovascular diseases that causes syncope which is not always accompanied by a prodromal symptom. Therefore, coronary spasm should be distinguished in patients with unexplained syncope or aborted SD.

Prediction of preserved flow to the infarct area based on admission electrocardiogram in anterior wall acute myocardial infarction

To determine whether preserved flow to the infarct area could be predicted from the admission electrocardiogram and to define the effect of preserved flow on the late results after reperfusion, 20 anterior myocardial infarction patients who were successfully reperfused were studied. Patients were divided into 3 groups: (1) no-flow group (8 patients), with an occluded infarct-related artery and no easily visible collaterals; (2) intact collateral group (6 patients); and (3) subtotal obstruction group (6 patients). From the admission electrocardiogram, the sum of ST-segment elevation (sigma ST), the sum of R-wave amplitude (sigma R) in leads V1 through V6 and the ratio of these (sigma R/sigma ST) were measured. There was no significant difference in sigma R among the 3 groups. The no-flow group had significantly lower sigma R/sigma ST and higher sigma ST than the intact collateral group or subtotal obstruction group. All patients (6 of 6) with subtotal obstruction and all except 1 patient (5 of 6) with intact collateral showed sigma R/sigma ST greater than 2.5 or sigma ST less than 2.0 mV. All patients (8 of 8) with no flow showed sigma R/sigma ST less than or equal to 2.5 and all except 1 patient with no flow (7 of 8) showed sigma ST greater than or equal to 2.0 mV. The regional wall motion was assessed by the radial method at 4 weeks. The mean percentage systolic shortening in the anterior and apical regions was significantly correlated with sigma R/sigma ST (r = 0.75, p less than 0.001) and sigma ST (r = -0.65, p less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

Possible role of coronary artery spasm in unexplained syncope

Coronary spasm provocation by intracoronary methylergonovine was performed in 14 patients (8 men and 6 women, mean age 56 +/- 6 years) with syncope that remained unexplained despite neurologic and noninvasive cardiac evaluations. Electrophysiologic testing was also performed in 6 of 14 patients. No patient had structural heart disease or significant fixed stenosis of greater than or equal to 75% in the coronary arteries. Six patients had no history of chest pain even when they developed syncope. Serious arrhythmia was documented in 2 patients, cardiac standstill in 1 and complete atrioventricular block in the other. Coronary spasm was induced in 9 patients using the methylergonovine provocation test. Multivessel spasms were found in 3 patients. Coronary spasm was induced in the artery supplying the inferior wall in 7 of 9 patients with positive results. In 4 of 9 patients who had a positive result, there was no prior history of chest pain. In 1 patient, whose electrocardiogram was recorded during syncope, cardiac standstill was documented and cardiac standstill and syncope also occurred during the provocation test. Monomorphic ventricular tachycardia was not induced by the electrophysiologic study. These results suggest that coronary spasm is involved in unexplained syncope.

Synthesis of human gamma-glutamyl transpeptidase (GGT) during the fetal development of liver

We have determined expression of human GGT gene encoding gamma-glutamyl transpeptidase (GGT) during fetal development of liver using the Northern-blot analysis with a cloned human GGT cDNA and immunohistochemistry with a monoclonal antibody. GGT mRNA could be detected as early as the 12th week of gestation. It then increased gradually to a peak of approx. threefold the amount at week 12, at week 40, just before birth. The size of the mRNA in the fetal liver was 2.7 kb and mRNA of the same size was detected both in the human fetal kidney and human hepatocellular carcinoma as well as normal adult liver. Immunohistochemical analyses show that GGT increased as the fetal liver developed in parallel with the increase in mRNA. Histochemically, GGT was shown to be located in the wall of bile canaliculi when synthesis was low in early development, but to be distributed, in addition, all over the cell membrane of the fetal hepatocytes when synthesis was high at the later stage of development.

Recanalization of experimental thrombotic arterial occlusion by radiofrequency thermal angioplasty: an angioscopic observation

The efficacy of radiofrequency (RF) angioplasty for recanalization of arterial thrombosis was assessed angioscopically in five dogs. A thrombus was induced by balloon injury of the left femoral artery. Within two hr, thrombi led to total occlusion of the artery in three dogs, subtotal occlusion in one, and about 70% obstruction in one. A metal-tipped catheter, with a tip size of 2.0 mm x 5.7 mm, was advanced into the thrombus and RF at 13.56 MHz was delivered repeatedly with gradually increased energies. The arterial lumina were recanalized or enlarged in all dogs. The thrombus surface had a shaggy appearance, and were dark (charring), or mixed dark and white in color. There were relatively large variations in the energies required; 140 J in one, 200 J in two and 250 J in two. The present results suggest that thrombotic arterial occlusion, such as acute occlusion complicating balloon angioplasty, can be treated with RF thermal angioplasty. Angioscopy provided detailed information about thrombus surfaces. The variations in required energies indicate the inability to control the thermal effect by energy settings alone. A more sophisticated method such as measurement of tip temperature will be able to overcome this difficulty.

A case of atrial septal defect combined with hypertension and left ventricular hypertrophy. Left ventricular failure induced by balloon occlusion and the effect of nifedipine

A 46 year old woman with hypertension and left ventricular hypertrophy accompanied by an atrial septal defect is reported. Hemodynamic changes induced by balloon occlusion and concomitant nifedipine were studied. Left ventricular failure appeared after balloon closure of the defect. Nifedipine decreased the increment in left ventricular end-diastolic pressure induced by balloon occlusion. After the reduction of systemic vascular resistance, the ratio of intracardiac shunt flow was still larger. Surgical closure of the defect was performed and the postoperative course was good with the use of vasodilators.

The primary structure of human gamma-glutamyl transpeptidase

A cDNA hybridizable to that of rat gamma-glutamyl transpeptidase (GGT) was cloned from a cDNA library of human fetal liver. The insert of the cDNA clone contained 1866 bp consisting of an open reading frame (ORF) of 1709 bp (569 amino acids (aa), N-terminal portion truncated) and a 135-bp 3'-untranslated region followed by a polyadenylated tail. In parallel, amino acid sequences of N-terminal portions of heavy and light chains of a purified human GGT were determined. Two stretches of amino acid sequences identical to the N-terminal sequences of heavy and light chains were found in the ORF. We therefore concluded that the clone is a cDNA for human GGT. From the amino acid sequence deduced from cDNA, the heavy and the light chains of the purified enzyme are estimated to be composed of 351 aa (Mr 38,336) and of 189 aa (Mr 20,000), respectively. The heavy chain is preceded by a signal peptide of at least 29 aa presumed to be cleaved by bromelain treatment. Six putative N-glycosylation sites are present in the heavy subunit region and one in the light subunit region. Primary structure and hydrophobicity profile are closely similar to those of rat GGT.