[Late malfunction of the Björk-Shiley valve prosthesis due to Delrin disc defacement]

A 55-year-old woman eighteen years after mitral valvular replacement with Delrin disc Björk-Shiley valve prosthesis underwent a reoperation of prosthetic valve replacement for the prosthetic malfunction due to disc defacement. The patient suffered from faintness and vertigo at rest. An echocardiographic examination showed a moderate mitral insufficiency with a normal disc movement. Precise examination on the removed prosthesis revealed accelerated defacement of disc margin which made the ring-disc clearance up to 0.35 mm and strut-shaped groove formation on the inlet surface of the disc occluder. These findings suggested a pronouncedly earlier disc wear than predicted by Björk and co-workers. We concluded, therefore, that a patient undergone a valve replacement with Delrin disc Björk-Shiley valve should be examined periodically by echocardiography even though being without any symptoms.

[A case report of BWG syndrome in an elderly patient performed with mitral valve replacement 11 years after single CABG]

A 46-year-old female who had undergone single CABG for BWG syndrome 11 years ago was referred to our hospital for paroxysmal atrial fibrillation. The roentgenogram showed slightly cardiomegaly and the enlargement of LA. Ischemic changes of ECG appeared at I, aVL, V5, V6, as inverted T wave, and low voltage R wave at V1-V4, but non Q wave. The thallium-201 emission computed tomogram at exercise revealed poor perfusion at apical region without redistribution pattern. Catheterization showed mitral regurgitation (grade III), big right coronary artery (RCA) arising from aorta, rich collateral to poor left coronary artery (LCA), and bypass graft was obstructed. The proximal end of LCA was closed, and didn't arise from both pulmonary artery and ascending aorta. In this cases, MVR only without re-CABG to LCA was selected and performed. Postoperative course was uneventful. The result of this case suggested that MVR was an effective surgical procedure for MR of BWG syndrome in the adult case and it was better to add CABG to LCA as much as possible if the ischemic region was large.

Antimicrobial activity of DV-7751a, a new fluoroquinolone

We compared the in vitro antibacterial activity of DV-7751a against gram-positive and -negative bacteria with those of quinolones currently available. MICs for 90% of the strains tested (MIC90s) against clinical isolates of methicillin-susceptible and -resistant Staphylococcus aureus and Staphylococcus epidermidis were 0.20, 0.39, 0.20, and 0.78 micrograms/ml, respectively. Moreover, MIC50s for DV-7751a against ofloxacin-resistant methicillin-resistant S. aureus were 4-, 8-, 16-, 32-, and 64-fold lower than those for tosufloxacin and sparfloxacin, levofloxacin, ofloxacin and fleroxacin, ciprofloxacin, and lomefloxacin, respectively. DV-7751a inhibited the growth of all strains of Streptococcus pneumoniae, Streptococcus pyogenes, and Peptostreptococcus spp. at 0.39, 0.39, and 0.78 micrograms/ml, respectively, and was 4- to > 16-fold more active against enterococci at the MIC90 level than the other quinolones tested. The activity of DV-7751a against Pseudomonas aeruginosa was roughly comparable to those of levofloxacin and sparfloxacin at the MIC90 level and was two- to fourfold less than that of ciprofloxacin. DV-7751a showed activity comparable to those of levofloxacin and ciprofloxacin against the other glucose-nonfermenting bacteria Haemophilus influenzae, Neisseria gonorrhoeae, and Moraxella catarrhalis (MIC90s of 0.025, 0.20, and 0.10 micrograms/ml, respectively). DV-7751a activity was not affected by medium, inoculum size, or the addition of human serum but was decreased under acidic conditions and in human urine, as were the other quinolones tested. Time-kill curve studies demonstrated the rapid bactericidal action of DV-7751a against S. aureus, S. pneumoniae, Escherichia coli, and P. aeruginosa. The frequency of spontaneous resistance to DV-7751a was less than or equal to those of the reference drugs. DV-7751a inhibited the supercoiling activity of DNA gyrases from S. aureus, E. coli, and P. aeruginosa at concentrations comparable to those of levofloxacin and sparfloxacin.

Overproduction of S-adenosylmethionine decarboxylase in ethylglyoxal-bis(guanylhydrazone)-resistant mouse FM3A cells

A variant cell line, termed SAM-1, which overproduced S-adenosylmethionine decarboxylase (AdoMetDC), was isolated by treatment of mouse FM3A cells with N-methyl-N'-nitro-N-nitrosoguanidine and subsequent incubation with ethylglyoxal bis(guanylhydrazone), an inhibitor of the enzyme. The cells were resistant to ethylglyoxal bis(guanylhydrazone), and showed AdoMetDC activity approximately five-times higher than control cells. The rate of AdoMetDC synthesis and the amount of AdoMetDC existing in SAM-1 cells were about five-times those in control cells. The amount of AdoMetDC mRNA existing in SAM-1 cells was five-times more than that in control cells. The amount of 5'-([(Z)-4-amino-2-butenyl]methylamino)-5'-deoxyadenosine, an irreversible inhibitor of AdoMetDC, necessary to inhibit cell growth was also five-times more in SAM-1 cells than in control cells. However, the following were the same in both SAM-1 and control cells; the amount of genomic DNA for AdoMetDC, the size and nucleotide sequence of 5' untranslated region of AdoMetDC mRNA, the deduced amino acid sequence (334 residues) from the nucleotide sequence of AdoMetDC cDNA and the degradation rate (t1/2 = about 4 h) of AdoMetDC. In addition, AdoMetDC mRNA in control cells was slightly more stable than that in SAM-1 cells. The results indicate that the overproduction of AdoMetDC in SAM-1 cells was caused by the increase of AdoMetDC mRNA. The variant cell line is convenient for studying the regulation of AdoMetDC and the physiological function of polyamines.

[Scintigraphic comparison of graft patency between the left internal thoracic artery and saphenous vein graft after coronary bypass surgery]

Graft patency after coronary bypass surgery (CABG) was evaluated with stress 201-thallium scintigraphy (stress 201Tl) in 26 cases, including 13 cases using the left internal thoracic artery (LITA group) in situ and 13 cases with saphenous vein graft (SVG group). All of them had effort or unstable angina caused by LAD lesion without apparent infarction. Stress 201Tl using a symptom-limited, graded bicycle exercise test was performed before CABG and 1 month, 6 months to 1 year, 1 year to 1.5 years after surgery. Five tomographic images including the apical side of the area fed by the bypass anastomosed to LAD in short axial sections were picked out and piled up. Fan-shaped ROI was made on this area and % Tl uptake was calculated using the following formula. 201Tl counts in ROI--Background counts/Maximum counts--Background counts x 100 (%) The normal % Tl uptake calculated in the control group (n = 11) in this ROI was 68.2 +/- 4.8%. Preoperative % Tl uptake showed 49.3 +/- 0.2% in the LITA group and 54.3 +/- 13.2% in the SVG group. % Tl uptake of the SVG group 1 month after CABG was slightly higher than that of the LITA group, (62.0 +/- 7.0% vs. 56.3 +/- 7.6%). However 6 months to 1 year after, % Tl uptake of the LITA group increased to 60.8 +/- 6.4%, inspite of a tendency on the decrease of that in the SVG group, (59.0 +/- 8.5%), and further more, 1 year to 1.5 years after CABG, increased to 62.3 +/- 5.1% near the normal % Tl uptake of the control group and the SVG group decreased to 58.8 +/- 6.8%. This result suggested that arterial in situ bypass graft might have an auto-regulation and "growing property" corresponding to flow demand, and this helps the excellent long-term patency of arterial bypass grafts.

Comparison of the effects on bronchial hyperresponsiveness of antiallergic agents and beclomethasone dipropionate in long-term bronchial asthma. A retrospective study

The effect of antiallergic agents (DSCG) (disodium cromoglycate, ketotifen, and ibudilast) and beclomethasone dipropionate inhaler (BDI) on bronchial hyperresponsiveness to histamine inhalation was retrospectively assessed in 72 asthmatic patients with more than a year's duration of the disease. Decrease in bronchial hyperresponsiveness to histamine was observed in 10 out of the 33 (30%) antiallergic-agents-treated patients (group A, mean duration = 7.8 months), in 12 of 19 (63.2%) BDI-treated patients (group B, 6.2 months), but only 2 of the 20 (10%) control patients (group C, 7.8 months). Improvement of histamine PC20 was from 310 to 597 micrograms/ml (P < 0.01) in group A, from 308 to 1622 micrograms/ml (P < 0.0005) in group B, and from 575 to 525 micrograms/ml (NS) in group C. A significant decrease in the peripheral eosinophil count was observed only in group B. The improvement in bronchial hyperresponsiveness was parallel with that of asthmatic symptoms; the percentage of patients becoming symptom-free rose from 12 to 42%, 5 to 89%, and 5 to 20% in groups A, B, and C, respectively. Out of 11 unimproved patients in group A, 7 showed a significant improvement in their histamine PC20 by BDI treatment (mean PC20: 311-->1828 micrograms/ml). These results suggest that BDI might be more effective than antiallergic agents in the treatment of patients with long-standing bronchial asthma.

[A case of mitral regurgitation caused by total rupture of the posterior papillary muscle after acute myocardial infarction]

We observed a case of severe mitral regurgitation caused by total rupture of the posterior papillary muscle 13 days after acute myocardial infarction. The patient was a 76-year-old man who suddenly felt anterior chest pain. He was admitted to another hospital with the diagnosis of acute myocardial infarction. Electrocardiogram suggested a posterior infarction. He did well during the first 12 days of hospitalization, but at noon on the 13th day he developed anterior chest pain and dyspnea. Echocardiography demonstrated rupture of the posterior papillary muscle. He was subsequently transferred to our hospital with acute heart failure. He was initially treated with an intra-aortic balloon pump. Cardiac catheterization demonstrated 99% stenosis of segment 2 of the right coronary artery and mitral regurgitation, Sellers' stage IV. Intraoperative findings included total rupture of the posterior papillary muscle. Mitral valve replacement was performed using a Carbomedics prosthetic valve. The patient was discharged 53 days after surgery without heart failure or angina pectoris. This case represents the 6th successful operation of total papillary muscle rupture in Japan.

[Myocardial revascularization with bovine internal thoracic artery graft (BIOFLOW): a case report]

Bovine internal thoracic artery graft (BIOFLOW) was used for coronary artery bypass grafting (CABG). A 64-year-old woman who had undergone triple CABG with saphenous vein five years ago was referred to our hospital again with anginal attack. Coronary angiogram showed the obstruction of the graft for LAD and new stenosis at right coronary artery (RCA). Gastroepiploic artery was not available because the patient had a history of gastric ulcer several times, and saphenous vein had harvested initial operation. We planned re-CABG for LAD with left internal thoracic artery and RCA with BIOFLOW. But at the operation, LAD was not graftable because of severe calcification. So that we performed single CABG to RCA with BIOFLOW. The BIOFLOW was patent at the 28 th postoperative day. From our experience, BIOFLOW can be expected as a graft for CABG when saphenous vein, internal thoracic artery and gastroepiploic artery are not available.

Bronchial hypersensitivity in asthmatics in long-term symptom-free state

Improvement of asthmatic symptoms was shown to be closely associated with a decrease in bronchial hypersensitivity to histamine inhalation. Thus, the patients' clinical backgrounds were compared between 26 long-term cases whose symptom-free state lasted more than 1 year and 15 short-term cases whose symptom-free state ceased within 1 year. Among backgrounds, only the intrinsic type of asthma was significantly higher in number in the long-term group than in short-term group (65 percent vs 27 percent). The histamine threshold after the patients became symptom-free was significantly higher in the long-term group. In the short-term group, the values of PC20 just before the termination of the symptom-free state were all less than 5,000 mg/L of histamine. However, in the long-term group, the values of the PC20 for the final test were mostly over 5,000 mg/L. Decrease in bronchial hypersensitivity is considered to be a very important aim of therapy in bronchial asthma.

Multiple regulation of ornithine decarboxylase in enzyme-overproducing cells

We have isolated from mouse FM3A cells a variant cell line, termed EXOD-1, that overproduces ornithine decarboxylase (ODC). The cells were resistant to alpha-difluoromethylornithine, an irreversible inhibitor of the enzyme, and produced the enzyme protein to the extent of approx. 3-6% of total cytosolic protein. The rate of ODC synthesis in this cell line accounted for 25-50% of the rate of total protein synthesis. The amounts of the ODC gene and its mRNA in the variant cells were both about 60 times as much as those in wild-type FM3A cells. Upon removal of the inhibitor, the growth of the ODC-overproducing cells was stimulated approx. 2-fold. Under these conditions, the rate of ODC synthesis increased about 4-fold on day 1 and then decreased to near the original level by day 3. The amount of ODC mRNA increased about 1.7-fold on day 1 and 2.5-fold on day 3. No correlation was observed between changes in ODC synthesis rate and in ODC mRNA content, suggesting a translational repression of ODC mRNA due to accumulation of polyamines. In fact, the cellular contents of putrescine and spermidine markedly increased and that of spermine inversely decreased during the same period. Pulse-chase experiments showed that the accumulation of putrescine and spermidine also elicited a rapid degradation of ODC. Excess amounts of newly synthesized putrescine and cadaverine were excreted into the medium, whereas spermidine, spermine and acetylated polyamines were undetectable there. We conclude that ODC regulation upon removal of the inhibitor is dependent on at least three steps, namely the level of mRNA, the translational efficiency of mRNA and the stability of the enzyme, the last two of which are involved in cellular polyamines.

A new gel using super absorbent polymer for mapping the spatial dose distributions of electron beams by MR imager

A technique for mapping the spatial dose distribution with a magnetic resonance imager is presented. A ferrous sulphate solution with sulfuric acid was used as the detecting medium for radiation dose. To make a gel of the solution for filling up a cubic phantom, we developed a new gel component that is combined with a super absorbent polymer (Sumikagel N-100) and a cross-linked dextran gel (Sephadex G-200). In order to make the application for radiation treatment planning, mapping of the dose distribution was carried out using a Unix computer.

Energy loss of 70 MeV protons in organic polymers

Using Bragg ionization curves, measurements of the average stopping power of organic polymers relative to that of water have been made for 70 MeV protons losing about 30 MeV in the absorbers. By comparing calculated curves to experimental ones, I-values for the polymers were obtained, relative to the I-value for A1. For repeated measurements with A-150 tissue equivalent plastic, the standard deviation of the ratio of the average stopping powers q was +/- 0.06%. It was found that q depends on the year of production of A-150. For other absorbers, the uncertainty of q is estimated to be +/- 0.2%, with a corresponding uncertainty of the I-values of +/- 1.5%. Most measured I-values exceed values calculated with the additivity rule by about 10%. During the course of the measurements, fluctuations of the proton energy from the cyclotron of up to 0.8% were found.

Superior mesenteric varices and splenic renal shunt with portal hypertension: a case report of liver cirrhosis with complications

The case of a 58-year old woman with cirrhosis complicated by hepatocellular carcinoma, hepatic encephalopathy and superior mesenteric varices is described. Angiography revealed large superior mesenteric varices and it was demonstrated that the portal venous blood was shunted into the right internal iliac vein via the right ovarian vein. Clinically, this patient had hepatic encephalopathy and hyperammonaemia, but no oesophageal varices were discovered on endoscopy. The hepatic encephalopathy suggested that the portal blood containing ammonium from the superior mesenteric vein entered the brain through the systemic vein without the ammonia being metabolized by the liver.

Euthanasia: current problems in Japan

Approximately 30 years ago, a son prepared a cup of milk mixed with insecticide and arranged for his mother to unknowingly administer the poison to his father, who had been suffering severe pain after a cerebral apoplectic attack and demanding that his son assist him. in dying. After drinking the mixture, the father died, and the son was charged with homicide.

[A case of coronary artery-pulmonary artery fistula in tetralogy of Fallot with pulmonary atresia and major aortopulmonary collateral arteries (MAPCA)]

A case of four year old girl with tetralogy of Fallot, pulmonary atresia, major aortopulmonary collateral arteries and coronary artery to pulmonary artery fistula is reported. The patient was misdiagnosed as truncus arteriosus, pulmonary stenosis and major aortopulmonary collateral arteries (MAPCA) preoperatively. The ligation of MAPCAs was carried out through left thoracotomy as an initial procedure, because we believed that the area fed by MAPCAs had dual blood supply. However, the patient demonstrated pulmonary infarction post operatively. This complication forced us to postpone an intracardiac repair. At the time of intracardiac repair, after mentioned diagnosis was established and a Rastelli type operation and ligation of coronary-pulmonary artery fistula were carried out. A 18 mm Carpentier-Edwards valved conduit was used as an extracardiac conduit.

IN CONCLUSION

1) We experienced a rare association of coronary artery fistula in TOF with PA. 2) The MAPCAs functioning as a sole source of blood-supply to the lung should be precisely diagnosed preoperatively and uniforcalized before an intracardiac repair.

DNA index as a significant indicator of lymph node metastasis and local recurrence of rectal cancer

To confirm the prognostic significance of the DNA index (DI) in cases of rectal cancer, the nuclear DNA content of tumor cells was examined in 184 cases of rectal cancer treated with curative surgery, and the incidence of lymph node metastasis and recurrence of the cancer was analyzed. The incidence of lymph node metastasis was 43.9 percent in cases with aneuploidy (DI above 1.5), being statistically different from the 18.0 percent incidence in cases with diploidy (P < 0.001). Although the extent of lymph node metastasis was limited to adjacent lymph nodes in cases with diploidy, distant lymph node metastases were frequent in cases with aneuploidy, especially in those with a DI above 1.5. Furthermore, the incidence of recurrence of cancer, and especially of local recurrence, was significantly higher (P < 0.001) in cases with aneuploidy (DI above 1.5) than in cases with diploidy and aneuploidy (DI below 1.4). These findings indicate the significant value of the DNA index for the prediction of lymph node metastasis and local recurrence in patients with rectal cancer.

Latero-terminal neurorrhaphy without removal of the epineural sheath. Experimental study in rats

Termino-lateral neurorrhaphies have been used up to the beginning of this century. After this period, they have no longer been reported. We tested the efficacy of a new type of latero-terminal neurorrhaphy and evaluated the role of the epineural sheath. A group of 10 rats had the fibular nerve sectioned and the distal ending was sutured to the lateral face of the tibial nerve without removing the epineurium. All experiments were made on the right side, the left one remaining untouched in half of the animals of each group. The other half were denervated by sectioning and inverting the endings of the fibular nerves. In this way, tibial cranial muscles were either normal or denervated in the left side and reinnervated through latero-terminal neurorrhaphy in the right side. After 7.7 months, the animals were subjected to electrophysiological tests, sacrificed, and the nerves and muscles were taken for histological exams. A response of the tibial cranial muscle was obtained in 75% of the animals. The distal ending of the fibular nerve showed an average of 498 nerve fibers. The average areas of the reinnervated tibial cranial muscles were (mu 2):841.30 for M2n and 1798.33 for M2d. We concluded that the termino-lateral neurorrhaphy was functional, conducting electrical stimuli and allowing the passage of axons from the lateral surface of a healthy nerve, to reconstitute the distal segment of a sectioned nerve. The presence of the epineurium was no impediment to axonal regeneration or to the passage of electrical stimuli.(ABSTRACT TRUNCATED AT 250 WORDS)

Hypothalamic GnRH pulse generator activity during the estradiol-induced LH surge in ovariectomized goats

Electrophysiological manifestation of the hypothalamic GnRH pulse generator activity was examined during the LH surge induced by estradiol in ovariectomized goats. The characteristic increases in the frequency of multiple unit activity (MUA volley) associated with the pulsatile secretion of LH were recorded using electrodes implanted bilaterally in the medial basal hypothalamus. Estradiol was infused for 16 h at the rate of 3 micrograms/h, to induce an LH surge 10.0-11.5 h later. Regular recurrence of MUA volley was observed throughout the experimental period including the LH surge, but the interval between the MUA volleys became longer (p < 0.01) after the onset of the LH surge as compared with the pretreatment control period (32.9 +/- 2.1 vs. 60.0 +/- 5.1 min). These results suggest that an increased frequency of LH pulses is not a prerequisite for the LH surge in ovariectomized goats given estradiol, and imply that the positive feedback effects of estradiol on LH secretion appear to be exerted through a neuronal mechanism that is intrinsically different from the GnRH pulse generator.