Co-expression of X-hapten-like antigen and antigen YH206 on mucin molecules

The asialocarbohydrate antigen YH206 is expressed on adenocarcinoma-associated mucin molecules which lack epitopes of CA19-9 and DU-PAN-2. To further characterize this molecule, the monoclonal antibody BM2 against the affinity-purified antigen YH206 was established. It was demonstrated by an inhibition test that antigen BM2 was an X-hapten-like structure, one of the representative oncodevelopmental antigens. Although the sensitivity of antigen BM2 in sera of stomach and pancreas cancer patients did not appear to be superior to that of antigen YH206, both antigens were complementary to each other resulting in the improvement of sensitivity. Interestingly, double-determinant enzyme immunoassays showed that antigen BM2 and YH206, both having a cryptic nature for neuraminidase, were co-expressed on the same mucin molecule in sera of patients with stomach cancer or liver cirrhosis. These data suggest that mucin molecules in serum might be classified into several groups based on the distribution of tumor-associated epitopes.

[Detection of the new tumor marker MUSE 11 antigen in sera of pancreatic cancer patients: a comparison with sialyl SSEA-I antigen]

Using sera from patients with pancreatic cancer and chronic pancreatitis, we measured the level of the adenocarcinoma-associated antigen MUSE 11. A comparative study between levels of MUSE 11 and levels of sialyl SSEA-1 antigen (SLX) was also carried out. With respect to the MUSE 11 antigen, positive incidence was found in 17 out of 26 pancreatic cancer patients (65%), and in 1 out of 13 chronic pancreatitis patients (8%). Similar results were obtained from the assay of SLX levels. However, no correlation was found between the two markers. Out of 9 samples which showed MUSE 11 negative, three were positive for SLX. Out of 13 samples showing SLX negative, seven were positive for MUSE 11. Twenty out of 26 (77%) cases showed positive results for either antigen. These data suggest that the MUSE 11 antigen may be useful for the diagnosis of pancreatic cancers.

Effects of ulinastatin in experimental acute arterial occlusion in rats

The effects of ulinastatin (human urinary trypsin inhibitor, UTI) were studied in experimental acute arterial occlusion in rats. The experimental model comprised concurrent cross-clamping of the abdominal aorta and bilateral femoral arteries for 4 hours. Blood was sampled for measurement of the enzymes 2 hours after release of the clamps. The rats were grouped according to method of infusing UTI and/or physiologic saline solution. When UTI was infused continuously from the start of clamping, the plasma creatine phosphokinase and plasma beta-glucuronidase levels were significantly lower than in the control rats (p less than 0.05). The results suggest that UTI prevents the destruction of the lysosomal membrane in acute arterial occlusion.

Significance of fill-in after thallium-201 reinjection following delayed imaging: comparison with regional wall motion and angiographic findings

To identify reversible defects, reinjection of a small amount of thallium-201 (201Tl) following 3-hr delayed imaging was performed in 60 patients with coronary artery disease who had perfusion abnormalities on their post-exercise 201Tl images. Thallium-201 uptake was visually scored and judged as normal (Group 1), reversible defect (Group II), new fill-in after reinjection (Group IIIa) and no fill-in even after reinjection (Group IIIb). New fill-in after reinjection was observed in 27 segments of the 85 segments (32%), showing persistent defect on the stress and delayed images. The wall motion in Group IIIa was worse than Group II but better than Group IIIb. Group IIIa showed Q-wave on ECG more often (69%) than Group II (27%) (p less than 0.01), but less often than Group IIIb (85%) (p less than 0.05). These data indicate that the reinjection 201Tl imaging often identifies new fill-in in the areas of no redistribution on the delayed images and it may hold promise for assessing tissue viability which the conventional imaging may underestimate.

Value of thallium-201 reinjection after delayed SPECT imaging for predicting reversible ischemia after coronary artery bypass grafting

The reinjection of a small dose (40 MBq) of thallium-201 after stress and delayed imaging often shows new redistribution in the regions with persistent defect. To assess whether these segments may represent reversible ischemia, reinjection thallium-201 single-photon emission computed tomography (SPECT) was performed after stress and 3-hour delayed imaging in 24 patients before coronary artery bypass grafting (CABG). The left ventricular myocardium was divided into 5 myocardial segments and regional wall motion was scored on a scale from 0 (normal) to 4 (dyskinesia). Thallium-201 findings were compared with improvement in regional perfusion and wall motion 1 to 2 months after CABG. The reinjection imaging identified new redistribution in 15 of 32 persistent defects (47%) on the 3-hour delayed images. In the study of stress and delayed SPECT imaging, the improvement in perfusion was observed in 34 of 43 segments (79%) exhibiting redistribution and 15 of 32 (47%) segments without redistribution (p less than 0.01). The reinjection SPECT identified new redistribution in 12 of the 15 improved segments that were not detected on the delayed images. Similarly, the improvement in wall motion was observed in 23 of 31 segments (74%) exhibiting redistribution and 14 of 30 segments (47%) without redistribution on the delayed images (p less than 0.05). The reinjection identified new redistribution in 10 of the 14 improved segments that were undetected on the delayed images. The predictive values for improvement in perfusion and wall motion by the reinjection imaging were significantly higher (92 and 89%) than those by the delayed imaging (69 and 62%, respectively, p less than 0.05 each).(ABSTRACT TRUNCATED AT 250 WORDS)

[Long-term results after total correction of tetralogy of Fallot]

One hundred sixty-two patients underwent total correction of tetralogy of Fallot from 1962 to 1979. 130 of these were hospital survivors. We studied the current status of the hospital survivors by questionnaires which were sent to 93 patients. An excellent long-term result was maintained by 87.3% of the 63 hospital survivors who answered to the questionnaires. Although there was a trend toward a higher incidence of symptoms in patients with a higher late postoperative RV/LV pressure ratio and in patients with older age at repair, it did not reach statistical significance. Six patients in this series have undergone reoperation. The most common cardiac problem which required reoperation was residual of the VSD. There was one late sudden death postoperatively. The RV/LV pressure ratio of the patient was 0.7 and the electrocardiogram at rest showed no abnormality except CRBBB. The ventricular dysarrhythmia was supposed as the cause of sudden death. The patients who underwent total correction of tetralogy of Fallot should be followed up by exercise ECG or 24 hours electrocardiographic monitoring.

The participation of sterol carrier protein2 in cholesterol esterification in rat adrenal microsomes

The effect of sterol carrier protein2 (SCP2) purified from rat liver on the formation of cholesterol esters by acyl-CoA: cholesterol acyl-transferase (ACAT: EC 2.3.1.26) in rat adrenal microsomes was studied. The rate of incorporation of [1-14C]oleoyl-CoA into cholesteryl oleate was determined in the presence or absence of exogenously added cholesterol or SCP2, or both. The addition of SCP2 had no effect on the formation of cholesterol esters from endogenous cholesterol by ACAT in rat adrenal microsomes. In contrast, the formation of cholesterol esters from exogenous cholesterol by ACAT was dose-dependently increased by the addition of SCP2. These experiments showed that SCP2 had an enhancing effect on cholesterol esterification by ACAT in rat adrenal microsomes most likely by modulating the availability of exogenous cholesterol and that SCP2 may participate in the formation of cholesterol esters in the rat adrenal gland.

[The recent trend of coronary surgery]

As the use of PTCA (Percutaneous Transluminal Coronary Angioplasty) is progressively widespread, the indication of CABG (Coronary Artery Bypass Grafting) and its candidates are changing accordingly. At present the candidates for CABG have left main trunk disease or severe triple-vessel disease, which are difficult or too dangerous to undergo PTCA. We should also note the population of operative candidates is becoming gradually older than before. The results from CABG appear to be limited according to the random follow-up studies in Europe and United States. The recurrence of angina and myocardial infarction tends to happen after five years. Our follow-up study shows the same tendency as those studies abroad. In order to improve the long-term results of CABG, we recommend the use of arterial grafts such as internal mammary artery, opt to the complete revascularization, and follow the patients postoperatively maximum medical therapy. At the same time, we should stress the importance of deciding the best operative opportunity, and not hesitate to make the decision for reoperation if it became necessary. Older candidates have tendency to suffer from neurological or respiratory complications during the postoperative period. If the risk of those complications appears great from the preoperative examination, we must make efforts to prevent those complications and finish CABG in the shortest possible time. Recently the cases for emergent CABG are decreasing for unstable angina or acute myocardial infarction, because PTCA is more effective for a short time. Time appears to be the most limiting factor for emergent coronary revascularization. Therefore the indication of emergent CABG is left only for left main trunk disease or severe triple vessel disease with complete occlusion of two coronary vessels. As a conclusion, CABG should be considered as only a palliative therapy same as PTCA and other medical treatments. Therefore the treatment of ischemic heart disease must be constituted by a integrated strategy including PTCA and drug therapy arranged for each patient.

Significance of adenocarcinoma-associated antigen YH206 levels in the pancreatic juice

We measured the pancreatic juice levels of antigen YH206, which is a new tumor marker of adenocarcinomas detected by monoclonal antibody YH206 (Hinoda et al., Int. J Cancer 24(5):653-658, 1988). Sandwich enzyme immunoassay revealed that samples from patients with pancreas cancer (n = 21) showed significantly higher values (P less than 0.01) than those of healthy controls (n = 15). Eight out of 21 (38.1%) samples from patients with pancreas cancer showed more than 100 U/ml, whereas only one out of 20 (5.0%) from patients with chronic pancreatitis exhibited more than 100 U/ml of antigen YH206. Simultaneous measurement of antigen YH206 and CA19-9 demonstrated that although a higher incidence of positivity in the case of pancreas cancer was obtained for both antigens, antigen YH206 showed much lower incidence of positivity (14%) than CA19-9 (57%) in patients with chronic pancreatitis. Therefore, the measurement of antigen YH206 in the pancreatic juice could be of use for the diagnosis of pancreas cancer.

[Repair of pure mitral insufficiency--experience in 50 patients]

Between February 1982 and March 1987, 50 adults underwent mitral valve repair for pure mitral insufficiency representing 54% of all adults having mitral valve surgery for pure mitral insufficiency. Ages ranged from 20 to 73 years (50.0 +/- 11.6). Anterior leaflet prolapse was present in 11, posterior leaflet prolapse in 26 and annulus dilation in 13. The mitral valve was repaired by quadrangular resection in 21, triangular resection in 2, plication without resection in 4, chordal shortening in 8 and annuloplasty alone in 15. Commissural annuloplasty was performed in addition to leaflet repair or chordal shortening in other 14 patients. The competence of the mitral valve was usually evaluated under beating conditions. 79% of the attempted repairs was considered successful in the posterior leaflet, contrasting to only 37% in the anterior leaflet. Prolapse of the anterior leaflet remains a surgical challenge. There were two early deaths (4%). During the follow up period (Mean 1.9 years, range 0.2-5.2 years), 2 late deaths (4%) were observed, one of them from thromboembolism, before adopting the policy of routinely anti-coagulating these patients during the first few months. 4 patients (9%), early in our experience, required reoperation within 4 months of surgery: two for severe mitral insufficiency and two for severe mechanical hemolysis. At reoperation, residual insufficiency was present in one, valve suture tear due to technical imperfection in two and complete disruption of the valve tissue at the suture line in one. Four additional patients had transient mechanical hemolysis requiring no specific therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effects of lidocaine and its metabolite, monoethylglycine xylidide (MEGX), on transmembrane action potentials in guinea-pig papillary muscles]

Effects of lidocaine 5, 10, 20 micrograms.ml-1 and its metabolite, MEGX 5, 10, 20 micrograms.ml-1, on transmembrane action potentials were studied in isolated guinea-pig papillary muscles, perfused with modified Tyrode's solution. The basic driving rate was 1 Hz and the rate was changed from 1 Hz to 0.25, 0.5, 2, 3 and 4 Hz in a stepwise manner. Both lidocaine and MEGX produced dose- and rate-dependent depression of maximum rate of rise of action potential (Vmax) without significant changes in resting membrane potentials. The recovery kinetics of Vmax was studied by either applying premature stimuli at basic driving rate of 0.25 Hz or by stopping the basic driving of 1 Hz for 1s to 60s. A slow component (time constant: 176-206 ms for lidocaine, 300-340 ms for MEGX) was observed in premature response. And a slower component (time constant: 3-4s for MEGX) was observed in the first response after stopping stimulation. Both drugs shortened the action potential duration. These results suggest that MEGX has a lidocaine-like class I antiarrhythmic actions and that it might modify the actions of lidocaine especially in patients with elevated plasma MEGX concentration.

Atrial pacing stimulates secretion of atrial natriuretic polypeptide without elevation of atrial pressure in awake dogs with experimental complete atrioventricular block

To clarify whether or not tachycardia stimulates the secretion of atrial natriuretic polypeptide (ANP) without elevation of atrial pressure, we examined the effects of atrial pacing on ANP secretion in awake dogs with normal sinus rhythm and with complete atrioventricular block (CAVB), which was produced surgically by heat cauterization of His' bundle. In four dogs with normal sinus rhythm, atrial pacing increased the atrial rate from 146 +/- 20 to 260 +/- 10 beats/min, with marked elevation of right atrial pressure (from 0.2 +/- 0.1 to 3.9 +/- 0.8 mm Hg) and left atrial pressure (from 0.2 +/- 0.1 to 8.6 +/- 2.8 mm Hg). Along with the hemodynamic changes, the ANP level in plasma obtained from the coronary sinus was increased from 405 +/- 99 to 849 +/- 199 pg/ml (p less than 0.01). In five dogs with CAVB, the ANP level was also significantly increased from 730 +/- 82 to 1,137 +/- 35 pg/ml (p less than 0.01) by rapid atrial pacing (from 164 +/- 20 to 317 +/- 30 beats/min) in spite of the lack of any appreciable changes in either left or right atrial pressure. Furthermore, in the CAVB group, while the ventricular rate was increased by ventricular pacing from 52 +/- 5 to 146 +/- 16 beats/min, atrial pacing was performed simultaneously without atrioventricular (A-V) sequential form. Even under this condition, the ANP level was increased from 480 +/- 172 to 626 +/- 223 pg/ml (p less than 0.05) without any substantial changes in atrial pressure. Such effects of rapid atrial pacing on ANP secretion were suppressed after infusion of autonomic blocking agents.(ABSTRACT TRUNCATED AT 250 WORDS)

[Assessment of resting thallium-201 reinjection after stress-delayed Tl imaging (I): Comparison with 24-hour scan and regional wall motion]

Clinical value of resting reinjection of 1 mCi (37 MBq) of Tl after stress-delayed scan was assessed in comparison with 24 hr delayed scan and regional wall motion (RWM) in 37 patients with coronary artery disease. Of 101 segments with initial perfusion abnormality, concordant findings were observed after Tl reinjection in 67 segments (66%). But redistribution (RD) after Tl reinjection was observed in 19 of the 52 persistent defect (PD) segments (37%), and complete RD was observed 15 of the 43 segments (35%) where 3 hr scan showed incomplete RD. On the other hand, concordant findings were observed on 24 hr delayed scan in 11 of the 20 segments with perfusion abnormality (55%). RD on 24 hr delayed scan was observed in 5 of the 13 PD (38%), but it was not apparent in 3 of the 7 segments where 3 hr scan showed RD. Furthermore the segments which showed RD after Tl reinjection in PD segments tend to have less severe RWM abnormality than the sustained PD segments (RWM score: 1.65 +/- 1.17 vs. 2.29 +/- 1.05, p less than 0.05). These data indicate that Tl reinjection which permits assessment of RD with good quality images on the same day is considered as a valuable means for assessing myocardial viability.

[Changes in the immune response in postoperative patients while running the ventricular assist device (VAD)]

We examined the immunological parameters in two patients who were assisted with LVAD in postoperative LOS. Both patients demonstrated transient consumption of complements immediately after running the LVAD. The serum concentrations of immunoglobulins (IgG, IgM, IgA) showed no significant decrease. Both patients had significant postoperative lymphopenia, but recovered in a week. A decrease in the number of T cells was observed in both patients. The OKT4/OKT8 ratio initially increased in one patient, but gradually declined postoperatively. In the other patient, the OKT4/OKT8 ratio decreased. The lymphocyte response to mitogen (PHA) remained significantly depressed when the number of lymphocytes returned to the normal level, suggesting that the lymphocytes were functionally impaired. Such findings are generally observed after cardiac surgery. Thus, LVAD does not affect the immune response.

Immunohistological and immunochemical characterization of a novel pancreatic cancer-associated antigen MUSE11

Using the ascites fractions of a cancer patient as an immunogen, we have recently prepared an interesting monoclonal antibody (MoAb), MUSE11 (IgG1), to a circulating pancreatic cancer-associated antigen (antigen MUSE11). Immunoperoxidase study revealed that antigen MUSE11 was detected in virtually all adenocarcinomas (especially pancreatic carcinoma), whereas it was either negative or faintly positive in their normal counterparts among the digestive organ tissues. Western blotting analysis and periodic acid-Schiff carbohydrate staining revealed that antigen MUSE11 is a Mr 300,000 glycoprotein that is clearly different from other high-molecular-weight glycoprotein antigens which have been used for detection of circulating antigens in pancreatic cancer patients. MoAb MUSE11 appears to react with a peptide epitope of this molecule, since periodic acid and neuraminidase treatment of the antigen did not affect the reactivity of MoAb MUSE11 with the antigen, but trypsin and protease treatment abolished the reactivity. The antigen MUSE11 was purified using affinity chromatography in conjunction with MoAb MUSE11. This antigen appears to be highly glycosilated with N-linked carbohydrate moieties, since treatment of the pancreatic carcinoma Panc-1 cells with tunicamycin reduced the molecular weight band to Mr 110,000. Once antigen MUSE11 has been purified by affinity chromatography, neither CA19-9 nor pancreatic oncofetal antigens can be detected, although they were present at very high levels in the crude ascitic starting material.

TSK-Toyopearl gels for the preparative separation of sterol carrier protein2 from rat liver

The application of TSK-Toyopearl gels to the preparative separation of a basic and low-molecular-weight protein, sterol carrier protein2 (SCP2), was studied. SCP2 was purified from 105,000 g supernatant of rat liver (S105) by ion-exchange chromatography on CM-Toyopearl 650M and gel permeation on Toyopearl HW60S. Separation of S105 by CM-Toyopearl 650M was carried out at a high flow-rate in the presence of 10% (v/v) glycerol, a stabilizer of the protein. Toyopearl HW60S showed a significant ion-exchange effect on the elution of SCP2. Using an elution buffer of ionic strength of 45 mM, a highly efficient purification of SCP2 on HW60S was achieved. SCP2 was purified approximately 5000-fold to apparent homogeneity with an overall yield of 69%.

Quantitative analysis of regional wall motion by gated myocardial positron emission tomography: validation and comparison with left ventriculography

Electrocardiographically gated positron emission tomography (ECG-gated PET) with [13N] ammonia was used to assess regional myocardial wall motion of left ventricle (LV) based on a nongeometric method in nine healthy volunteers and 16 patients with coronary artery disease (CAD). Three transverse sections (upper, middle, and lower) with 16-mm intervals at end-diastole (ED) and end-systole (ES) were analyzed. The LV wall was divided into eight segments with every 30 degrees from septal wall to lateral wall. Based on circumferential profile analysis, the percent count increase [( ES count - ED count) divided ED count x 100) in each segment was analyzed as an index of regional wall motion. In the study of normal controls, the percent count increase was the lowest (32.9 +/- 7.2%) at septal wall of the lower slice and the highest (72.8 +/- 26.5%) at lateral wall of the upper slice (p less than 0.01). In five normal controls, the percent count increase was compared with the percent systolic wall thickening analyzed by magnetic resonance imaging, and a good correlation was observed (r = 0.84). In the study of patients with CAD, the percent count increase was compared with wall motion assessed by left ventriculography (LVG). The percent count increase significantly decreased as wall motion on LVG worsened. In addition, the value in normal controls tended to be higher than that in the segments with normal wall motion in patients with CAD. Thus, quantitative analysis of regional wall thickening was feasible by ECG-gated PET, which should be useful for combined analysis of regional function, perfusion and metabolism in patients with CAD.

[Aortic aneurysm associated with coarctation of the aorta]

An 8-year-old female of coarctation of the aorta associated with thoracic aortic aneurysm is reported. Under cardiopulmonary bypass, a 7 cm section of the aorta containing the aneurysm and coarctation was resected and replaced by a 16 mm woven Dacron tube. The postoperative recovery was complicated by chylothorax treated by thoracic aspiration. She is doing well 3 months after the operation. Histologic sections of the resected portions of the thoracic aorta revealed intimal hyperplasia, medial fibrosis and decrease of elastic fibers, especially in the aneurysm.

Effects of coronary artery bypass surgery on regions showing persistent defects in thallium myocardial images

The indications for revascularization surgery and its effects on myocardial regions showing persistent defects in thallium myocardial images are controversial. The effects of aortocoronary bypass surgery on myocardial perfusion and wall motion in the regions with persistent defects were evaluated in 47 patients with thallium-201 single photon emission computed tomography and left ventriculography. In areas showing persistent thallium defects preoperatively the rate of improvement of perfusion was only 24% by postoperative thallium imaging, and 57% by wall motion analysis. These results were significantly inferior to those of regions with transient defects, which were 84% and 82%, respectively. A persistent defect may not be a definitive marker of a non-viable scar, but the results of surgery on such regions were unsatisfactory. It is concluded, therefore, that revascuralization surgery in regions with persistent defects is not always recommended and that the indications for surgery should be individually determined with operative risk balanced against benefits.

Assessment of transesophageal Doppler echography in dissecting aortic aneurysm

To assess the clinical value of transesophageal Doppler echography in the diagnosis of dissecting aortic aneurysm, both transesophageal and conventional echograms were performed in 22 cases of dissecting aortic aneurysm. Of the 22 patients, 17 underwent angiography; 8, X-ray computed tomography; 4, both; and 12, surgery. The performance of each method was assessed in the following four segments: A, ascending aorta; B, aortic arch; C, thoracic descending aorta; and D, upper abdominal aorta. The results by angiography were presumed to be correct. In the group of 17 patients who underwent angiography, the rate of correct detection of an intimal flap using the transesophageal approach was 100% in all four segments, significantly better than detection by the conventional approach (segment A, 65%; segment B, 47%; segment C, 35%; segment D, 53%) (p less than 0.01), and the rate of correct detection of the entry sites using the transesophageal approach was 100%, significantly better than that by conventional approach (42%) (p less than 0.05). X-ray computed tomography was not capable of detecting the site of entry in all cases. The presence of thrombus, aortic regurgitation and pericardial hemorrhage were all revealed clearly by the transesophageal approach, and the results were partly proved by other methods. In conclusion, transesophageal Doppler echography provides a rapid and accurate method of diagnosing and evaluating dissecting aortic aneurysm and permits prompt initiation of appropriate treatment.

Positron emission tomography using fluorine-18 deoxyglucose in evaluation of coronary artery bypass grafting

To assess the clinical value of positron emission tomography (PET) in the evaluation of coronary artery bypass grafting (CABG), PET perfusion and metabolic imaging using nitrogen-13 ammonia and fluorine-18 deoxyglucose (FDG) was performed before and 5 to 7 weeks after CABG in 22 patients with coronary artery disease. Postoperative improvement in hypoperfusion was observed more often in the metabolically active segments (62%) than in the inactive segments (27%) on the preoperative PET study (p less than 0.05). Similarly, the postoperative lessening of wall motion abnormality was observed more often in the metabolically active segments (78%) than in the inactive segments (22%) (p less than 0.001). Of 19 asynergic segments showing increased FDG uptake before operation, the postoperative PET revealed a decrease in FDG uptake in 13 (68%) and persistent uptake in 6 (32%). The improvement in asynergy was observed in all the segments that showed a postoperative decrease in FDG uptake, but in only 50% of those with persistent uptake (p less than 0.01). On the other hand, 4 of 5 segments showing a new FDG uptake after operation revealed further wall motion abnormality. Furthermore, the segments metabolically active before operation were more likely to have patent grafts (95%) than the metabolically inactive segments (70%) (p less than 0.05). Thus, preoperative metabolic imaging using PET appears to be useful for predicting the response to CABG. Improvement in metabolic derangement was associated with improvement in regional function after CABG.

Ultrastructural and immunocytochemical studies on the cytoskeleton in the anterior pituitary of rats, with special regard to the relationship between actin filaments and secretory granules

As previously reported, in anterior pituitary cells of the rat, secretory granules are linked with adjacent granules, cytoorganelles, microtubules, and plasma membrane by thin filaments, 4-10 nm in diameter. The quick-freeze, deep-etching method revealed that some of the filaments linking adjacent secretory granules show 5 nm-spaced striations on their surface which are known to be characteristic of actin. Immunocytochemistry showed that actin is localized in the cytoplasm beneath the plasma membrane, and around or between secretory granules. The heavy meromyosin decoration method demonstrated that actin filaments are mainly located in the cytoplasm beneath the plasma membrane, while some actin filaments are connected with the limiting membrane of the secretory granules. The actin filaments associated with the secretory granules are considered to be involved in the intracellular transport of the granules, while those localized in the peripheral cytoplasmic matrix might control the approach of the secretory granules to the plasma membrane and their release.

[A case report of emergency Bentall re-operation]

A 51-year-old male of Marfan syndrome with annuloarotic ectasia underwent the Bentall operation. One and a half months later, he suddenly fell into the left ventricular failure associated with lung edema. Echocardiogram revealed total occlusion of the graft and aortic valve detachment was suspected. An emergency operation was performed. The aortic valve was completely detached due to infectious endocarditis. As anastomosed portions of the proximal coronary arteries and distal aorta were intact, these rims of the old graft were reserved. A new composite graft was anastomosed distally to the above reserved graft rims and sutured proximally to the trimmed aortic valvular ring. The patient survived the re-operation despite many post-operative complications such as mediastinitis, colon bleeding, renal failure and severe hepatic dysfunction.

Value of rest-stress myocardial positron tomography using nitrogen-13 ammonia for the preoperative prediction of reversible asynergy

To determine the predictive value of stress [13N]ammonia positron emission tomography (PET) for reversible ischemia, 31 patients with coronary artery disease underwent rest-stress [13N]ammonia PET before and after coronary artery bypass surgery. The circumferential profile analysis was applied to determine the presence of transient defect (TD) and persistent defect (PD) preoperatively, and the fate of perfusion abnormality and asynergy after the surgery was assessed. Preoperative PET demonstrated 100 segments with perfusion abnormalities, including 69 TD and 31 PD. Fifty-six of the 69 TD (81%) improved in regional perfusion, while only four of 31 PD (13%) improved in perfusion postoperatively (p less than 0.001). Of 75 segments showing regional asynergy on contrast or radionuclide ventriculography preoperatively, 34 of 48 segments with TD (71%) improved in asynergy, while only five of 27 segments with PD (19%) improved in asynergy postoperatively (p less than 0.001). Stress-delayed 201TI tomography was performed in 22 of them. The predictive values for improvement in perfusion (77%) and asynergy (65%) were similar as those by [13N]ammonia PET (81% and 71%, respectively). However, the predictive values for no improvement in perfusion and asynergy by 201TI tended to be low (66% and 58%, respectively), as compared to those in 13N ammonia PET (87%; p less than 0.05 and 81%; p = 0.09, respectively). We conclude that an accurate prediction of reversible ischemia and asynergy can be achieved with rest-stress [13N]ammonia PET. Particularly, it can identify irreversible areas more accurately than the commonly performed stress-delayed 201TI imaging.

Behavior of platelets and leukocytes on the luminal surface of small caliber polyurethane grafts

With scanning electron microscopy, we examined the behavior of platelets and leukocytes on the luminal surface of small caliber polyurethane grafts implanted into small arteries of dogs. Thirty-five grafts were implanted to the carotid and/or femoral arteries. The animals were treated with aspirin and/or DN9693, an inhibitor of phosphodiesterase. In the group treated with aspirin (40 mg/kg i.v.), the deposition of platelets on the luminal surface of the implanted polyurethane grafts was suppressed and the luminal surface was covered with adherent leukocytes. Fibrin nets were formed on the adherent leukocytes. In addition, the adhesion of leukocytes on the grafts was considerably suppressed in the group treated with DN9693 (50 micrograms/kg/min i.v.), and the formation of fibrin nets was markedly reduced. In contrast, in the control group the luminal surface was covered with numerous platelets and some leukocytes, which formed thrombi. These findings suggest that leukocytes adhere primarily to the prosthetic graft and play an important role in the initiation of fibrin formation.

Effects of lidocaine alone and in combination with tetraethylammonium on the maximum upstroke velocity in guinea-pig papillary muscles

Effects of 18.5 mumol/l lidocaine on the Vmax in the absence and presence of 10 mmol/l tetraethylammonium chloride (TEA), which specifically prolongs the action potential duration with little effects on Vmax, were studied in guinea-pig papillary muscles in a 10 mmol/l K+ Tyrode solution. The frequency-dependent reduction of Vmax was significantly increased at high frequencies (3 and 4 Hz) in the presence of lidocaine plus TEA. A simulation study was performed under the assumption that lidocaine interacts with open, inactivated and resting sodium channels and that TEA specifically prolongs the inactivated state, and a reasonable fit to the experimental Vmax changes was obtained. There were no significant differences between the effects of lidocaine alone and lidocaine plus TEA on the tonic blocks, time constants and zero-time intercepts of reactivation process of Vmax. The F-test shows that these reactivation processes in all preparations examined are described sufficiently well by monoexponential functions, that is, under the assumption of the linear relationship between available sodium conductance and Vmax. The finding that a nonlinear model does not significantly improve the fit indicates the possibility that the nonlinearity may not be prominent under the present experimental conditions.

[Transesophageal Doppler echocardiography in the diagnosis of dissecting aortic aneurysm]

Transesophageal Doppler echocardiography (TEDE) was performed in three patients with proven or suspected DeBakey type I and type III aortic dissection. Case 1: A 66-year-old woman, with DeBakey type I aortic dissection. Clear images of a widened dissected aorta and an intimal flap were obtained in both the ascending and descending aorta, including the aortic arch. The site of an entry into the false lumen was identified by the defect of the intimal flap and the pulsatile entry flow through it. The reentry into the true lumen was also identified near the orifice of the celiac trunk. In this case, the observation was performed using this technique during the operation; i.e., replacement of the ascending aorta with an artificial graft. Case 2: A 77-year-old man, DeBakey type III aortic dissection. The study was performed after surgery which consisted of replacement of the descending aorta with an artificial graft. TEDE provided clear images of the artificial graft, the aorta, and their boundaries. The remaining intimal flap was clearly confirmed. Case 3: An 80-year-old man, DeBakey type III aortic dissection. In this case, though abdominal echography suggested aortic dissection, angiography and X-ray CT failed to facilitate the diagnosis. Only TEDE confirmed the diagnosis. The abnormal flow via the entry directing toward the false lumen was clearly demonstrated on the color Doppler images. We therefore conclude that TEDE is a useful and reliable means of diagnosing dissecting aortic aneurysm.

[Severe postoperative pulmonary hypertensive crisis in a case of ventricular septal defect with Down's syndrome]

We encountered the episode of severe postoperative pulmonary hypertensive crisis in a case of ventricular septal defect with Down's syndrome. A 1 year 11 month old female with ventricular septal defect and pulmonary hypertension underwent open heart surgery. On the operative day after tracheal suction she experienced bradycardia, hypotension and pulmonary hypertension followed by shock condition. In spite of vigorous medical therapy clinical aspects were not improved. But only blood transfusion directly into the left atrium and administration of tolazoline hydrochlorides through pulmonary artery were very effective to improvement of hemodynamics and reduction of pulmonary hypertension. Moreover, after this episode pulmonary artery pressure showed elevation at the tracheal suction and the weaning from the respirator. We discussed the cause and treatment of postoperative pulmonary hypertensive crisis.

Value of stress thallium-201 emission tomography for predicting improvement after coronary bypass grafting and assessing graft patency

To examine the value of stress and redistribution thallium-201 single photon emission computed tomography (SPECT) for predicting improvement after coronary artery bypass grafting (CABG) and for assessing graft patency, 17 patients underwent SPECT before and after CABG. Preoperatively, 16 patients (94%) showed reversible ischemia with redistribution, and defect score decreased from 16.4 +/- 7.6 to 8.3 +/- 5.8 (p less than 0.001) on 2 hour delayed images. Stress electrocardiography was positive in 15 cases (88%). The stress defect score was reduced postoperatively (7.8 +/- 6.3) as compared to the preoperative score (16.4 +/- 7.6) (p less than 0.001). Postoperatively, 7 cases (41%) showed reversible ischemia and the defect score decreased from 11.3 +/- 6.5 to 6.1 +/- 4.7 (p less than 0.05), while 4 cases (23.5%) showed positive stress electrocardiograms (ECG). Resting left ventricular (LV) ejection fraction (EF) improved in 6 cases (48.3 +/- 5.4% preoperatively to 56.8 +/- 7.4% postoperatively, p less than 0.05) and showed a reduction in 11 (58.2 +/- 10.5% to 47.5 +/- 9.4%, p less than 0.01). Grafts were occluded in 6 cases, and redistribution was evident on the delayed thallium images in all cases (100%), while stress ECG was positive in only 3 (50%). Thus, stress and redistribution SPECT is valuable for identifying patients who will improve after surgery and assessing graft patency more accurately than stress ECG. Resting LVEF was less useful for assessing improvement in LV function.

Sodium channel-blocking properties of flecainide, a class IC antiarrhythmic drug, in guinea-pig papillary muscles. An open channel blocker or an inactivated channel blocker

Effects of flecainide (a class IC antiarrhythmic drug) on the maximum rate of rise (Vmax) of action potentials (APs) were studied in guinea-pig papillary muscles, with special reference to their time, voltage, and action potential duration (APD) dependence in the presence and absence of nicorandil. Nicorandil was used to shorten APD, i.e., the time period of inactivation state of sodium channels. APs were recorded from the preparations using standard microelectrode techniques. Flecainide (5 mumol/l) reduced Vmax without changing resting potential, AP amplitude, APD50, and APD90 examined at 1 Hz. The drug shifted the normalized Vmax-membrane potential curve (examined at 1/60 Hz) in the hyperpolarizing direction by 3.1 +/- 0.8 mV (n = 6) (voltage dependence). The drug caused a frequency-dependent reduction of Vmax at greater than or equal to 0.1 Hz, developed a use-dependent reduction of Vmax at 1 Hz with an onset time constant of 11.7 +/- 0.4 s (n = 6), and slowed the recovery process of Vmax, whose resultant recovery time constant was 19.9 +/- 1.2 s (n = 6) (time dependence). These flecainide-induced time-dependent reductions of Vmax were not antagonized by nicorandil (1 mmol/l) which shortened APD to about 1/4 of control (APD independence). These results suggest that flecainide is primarily an open channel blocker because its channel-blocking actions are independent of APD or the time period of inactivation.

Effects of AFD-21, a new class I antiarrhythmic agent, and AFD-19, its active metabolite, on the maximal rate of rise of action potentials in guinea pig papillary muscles: dependence on time, voltage, and action potential duration

Effects of AFD-21 and AFD-19 (a new class I antiarrhythmic agent and its active metabolite, respectively) on the maximal rate of rise (Vmax) of action potentials (APs) were studied in guinea pig papillary muscles with special reference to their time, voltage, and action potential duration (APD) dependence. Both AFD-21 and AFD-19 (2-10 microM) reduced Vmax in a concentration-dependent manner without affecting the resting potential, APD, and effective refractory period. Both agents (5 microM) shifted the normalized Vmax resting potential curve (examined at 1 Hz) in the hyperpolarizing direction by 4-7 mV (voltage dependence). In addition, both agents (5 microM): a) caused a frequency-dependent reduction of Vmax at 0.25-3 Hz; b) developed a use-dependent (1 Hz) reduction of Vmax with an onset time constant of 1-3 s; and c) slowed the recovery process of Vmax, whose resultant recovery time constant was 2-3 s (time dependence). Nicorandil (1 mM), which shortens APD to about 25% of control, antagonized the AFD-21-induced time-dependent reductions of Vmax but not the AFD-19-induced reductions (APD dependence). These results suggest that the effects of AFD-21 on Vmax are APD dependent but those of AFD-19 are not, and thereby that AFD-21 and AFD-19 preferentially block inactivated and open sodium channels, respectively. The present findings are discussed from the viewpoint of the modulated or the guarded receptor hypothesis.

Immunochemical characterization of adenocarcinoma-associated antigen YH206

The antigen recognized by MAb YH206 is mainly expressed in adenocarcinomas and is also detected in the sera of cancer patients (Hinoda et al., 1987). This antigen (antigen YH206) was chemically characterized and purified by column chromatography. SDS-PAGE analysis revealed a broad component in the high-molecular-weight range which was clearly detectable by carbohydrate (PAS) but not by protein (silver) stain. Agarose gel electrophoresis and immunoblotting of antigen YH206 indicated that it consists of a high-molecular-weight component (more than 2,000 kDa). Treatment of antigen YH206 with alkali suggested that the antigenic determinant consists of carbohydrate chains of mucin type. Density gradient ultracentrifugation revealed that the activity of antigen YH206 is localized at a density of 1.45 g/ml, suggesting that antigen YH206 is a mucin. Neuraminidase treatment of antigen YH206 indicated that the epitope is cryptic and contains an asialocarbohydrate chain. Once antigen YH206 has been purified by affinity chromatography, neither CA19-9 antigen nor DU-PAN-II antigen can be detected, although they were present at very high levels in the crude ascitic starting material; these last two are representative carbohydrate antigens which are widely used for serodiagnosis to detect adenocarcinomas.

[Placental-site trophoblastic tumor of the uterus--a case report]

A case of placental-site trophoblastic tumor arising in the uterus is reported. The patient, a 34-year-old female, complained of irregular menstruation. Under the diagnosis of a tumor in the uterus or the ovary, a simple total hysterectomy and right adnexectomy were performed. Histologically, the tumor cells, which were large, polygonal or rounded in shape, had infiltrated into the myometrium in clusters or singly. Immunohistochemically, most of the tumor cells were positive to hPL. Further, hCG also was present in some tumor cells, though only weakly. Because of these findings, this case was diagnosed as a placental-site trophoblastic tumor (PSTT).

Scanning electron microscopy of cytoplasmic filaments in rat anterior pituitary cells

In order to demonstrate the occurrence of cytoplasmic filaments and their relationship to secretory granules, rat anterior pituitaries perfused with a detergent solution containing 0.5% Triton X-100 were observed with the scanning electron microscope. Thin section images and quick-freeze, deep-etching replica images were also studied. Scanning electron microscopy clearly demonstrated complicated networks of numerous cytoskeletal filaments in the cytoplasm of all the secretory cells of the anterior pituitary. These filaments can be classified into two groups on the basis of their diameter: thick filaments measuring 30-40 nm in diameter, and thin filaments 15-25 nm in diameter, each including the thickness of the platinum coat. The thick filaments, which run rather straight, are considered to be microtubules. The thin filaments attached to the surface of a secretory granule may connect it with an adjacent secretory granule, with cyto-organelles, with the nucleus, or with the plasma membrane. Transmission electron microscopic images of thin sections and quick-freeze, deep-etching replicas confirm the occurrence of filamentous structures associated with the limiting membrane of the secretory granule. The fine filaments associated with the limiting membrane of the secretory granule might participate in the support and transport of the granule.

Isolated interruption of the aortic arch

We report a case of a 4-year-old girl with interruption of the aortic arch without a patent ductus arteriosus or intracardiac shunts. The anomaly was successfully corrected with the use of a 14 mm Dacron prosthetic graft to bypass the interrupted segment. The postoperative course was uneventful.

Relation of left ventricular perfusion and wall motion with metabolic activity in persistent defects on thallium-201 tomography in healed myocardial infarction

Myocardial viability in persistent thallium (TI)-201 defect is a controversial subject. To assess metabolic activity in segments with persistent defect, stress TI-201 tomography and positron emission tomography using nitrogen-13 ammonia and fluorine-18 2-fluoro-deoxyglucose (FDG) were performed in 28 patients with healed myocardial infarction. The segments with TI-201 perfusion defect in electrocardiogram-determined infarcted areas were selected for assessment. Stress perfusion defect was detected in 61 segments by TI-201 tomography. Twenty-two patients (36%) showed transient defects with redistribution (group 1) and 39 showed persistent defects (group 2). Increase in FDG uptake was observed in 95% in group 1. Among group 2 patients, 15 segments (38%) showed an increase in FDG uptake (group 2A) while the remaining 24 (62%) did not have an increased uptake (group 2B). The decrease in nitrogen-13 ammonia perfusion was more severe in group 2B (-23 +/- 7%) than in group 2A (-13 +/- 9%) (p less than 0.005) and group 1 (-10 +/- 4%) (p less than 0.001). In addition, wall motion scores tended to be lower in group 2B (0.21 +/- 0.71), compared with group 2A (0.67 +/- 0.70) (p = 0.05) and group 1 (0.77 +/- 0.60) (p less than 0.01). These data indicate that metabolic viability was observed in approximately 40% of the segments with persistent TI-201 defect. Preservation of regional perfusion and wall motion in these areas was similar to that in areas with transient TI-201 defect.

Myocardial positron tomography with N-13 ammonia in assessment of aortocoronary bypass surgery

A total of 20 patients were examined at rest and during stress with N-13-ammonia myocardial positron emission tomography (PET) before and after aortocoronary bypass surgery in an attempt to evaluate the effect of surgery on myocardial perfusion and to predict the graft status. The PET images were divided into anterior, septal, apical, lateral and posteroinferior segments for analysis and were evaluated as "normal" (no perfusion defects during stress and at rest), "ischemia" (stress-induced defects) and "fibrosis" (persistent defects both at rest and during stress). Approximately 90% of the segments which were ischemic before surgery became normal after surgery. Thus, ischemic changes are highly reversible, and the vessels perfusing these ischemic areas are most suitable for bypass surgery. However, most of the persistent defects failed to respond to revascularization surgery and, hence, represented irreversibly damaged myocardium. In predicting graft status, graft patency could be demonstrated by normal perfusion in postoperative images (p less than 0.01) or by improved perfusion when pre- and postoperative images were compared (p less than 0.01). However, graft occlusion could not be predicted reliably. This study demonstrated that PET with N-13 ammonia was useful in the assessment of the effects of aortocoronary bypass surgery. However, this technique was not significantly superior to thallium-201 single-photon emission computed tomography for only qualitative analysis.