The catenin/cadherin adhesion system is localized in synaptic junctions bordering transmitter release zones

Molecular mechanisms linking pre- and postsynaptic membranes at the interneuronal synapses are little known. We tested the cadherin adhesion system for its localization in synapses of mouse and chick brains. We found that two classes of cadherin-associated proteins, alpha N- and beta-catenin, are broadly distributed in adult brains, colocalizing with a synaptic marker, synaptophysin. At the ultrastructural level, these proteins were localized in synaptic junctions of various types, forming a symmetrical adhesion structure. These structures sharply bordered the transmitter release sites associated with synaptic vesicles, although their segregation was less clear in certain types of synapses. N-cadherin was also localized at a similar site of synaptic junctions but in restricted brain nuclei. In developing synapses, the catenin-bearing contacts dominated their junctional structures. These findings demonstrate that interneuronal synaptic junctions comprise two subdomains, transmitter release zone and catenin-based adherens junction. The catenins localized in these junctions are likely associated with certain cadherin molecules including N-cadherin, and the cadherin/ catenin complex may play a critical role in the formation or maintenance of synaptic junctions.

Culture of cells derived from the human sebaceous gland under serum-free conditions without a biological feeder layer or specific matrices

We succeeded in serially culturing cells derived from human sebaceous gland (sebocytes) under serum-free conditions. Sebaceous glands were isolated from dispase-treated facial skin specimens and cultured using two different methods, explant culture and dispersed cell culture, in KGM. In both types of culture the sebocytes proliferated rapidly without a biological feeder layer or specific matrices. It was possible to cultivate the cells serially for at least three passages (explant culture) and six passages (dispersed cell culture), and to store the cells in liquid nitrogen with good recovery. Analytical thin-layer chromatography revealed that the cells synthesized a large amount of sebum-specific lipids, squalene and wax esters in vitro. Both testosterone and 5 alpha-dihydrotestosterone significantly stimulated the proliferation of the sebocytes. The methods presented here may permit a large series of studies on the function of sebaceous glands or cells derived from sebaceous glands.

[A case of ischemic necrosis on anterior chest wall and mediastinitis after coronary artery bypass grafting using bilateral internal thoracic arteries and inferior epigastric arteries]

Coronary artery bypass grafting using bilateral internal thoracic arteries and inferior epigastric arteries was performed in a 72-year-old man with multiple coronary artery disease who had a history of gastrectomy 25 years before. He postoperatively suffered from ischemic necrosis on anterior chest wall and mediastinitis caused by methicillin resistant staphylococcus aureus and aortic rupture. He got over by drainage at twice, hemostasis of aortic rupture and long-term irrigation using vancomycin. We must not perform coronary artery bypass grafting using bilateral internal thoracic arteries and inferior epigastric arteries at same time.

Primitive human hematopoietic cells displaying differential efflux of the rhodamine 123 dye have distinct biological activities

Human bone marrow (BM) CD34+ cells were stained with the vital dye, rhodamine 123 (Rh123), and analyzed for their biological properties based on the level of dye retention. Heterogeneous rhodamine staining is seen within the CD34+ population, and the staining patterns differ dramatically between fetal BM (FBM), adult BM (ABM) and mobilized peripheral blood (MPB). Kinetic analysis of the efflux of Rh123 from ABM CD34+ cells showed that efflux of Rh123 was most rapid from the most primitive Thy-1+ subset. The efflux of Rh123 could be inhibited by verapamil, suggesting that rhodamine efflux from primitive hematopoietic cells is primarily due to the P-glycoprotein (P-gp) pump or another intracellular transport system affected by verapamil. When four CD34+ subpopulations were plated onto SyS1 BM stromal cell cocultures after 1 to 2 weeks, only wells plated with CD34+ Thy-1+Rh123lo (low-level Rh123 retention) or CD34+Thy-1+Rh123mid (mid-level Rh123 retention) cells maintained greater than 50% of cells in an uncommitted CD34+33- stage. CD34+Lin- (lineage-negative) cells were fractionated based on Rh123 dye staining into Rh123hi (high-level Rh123 retention), Rh123mid, and Rh123lo and deposited as single cells into long-term SyS1 BM stromal cell cultures. The Rh123mid fraction had immense early proliferative activity in vitro, but lost the ability to form cobblestone areas after 5 to 6 weeks in culture. In contrast, the Rh123lo fraction proliferated more slowly but sustained long-term in vitro hematopoiesis as evidenced by continued cobblestone area-forming cells (CAFC) activity for at least 6 weeks. The Rh123hi fraction showed a plating efficiency similar to that of the Rh123lo or Rh1123mid fractions but did not extensively proliferative in vitro and did not show evidence of CAFC activity. We predicted from these in vitro results that the Rh123lo subsets possesses long-term engrafting potential. Indeed, on transplantation into the SCID-hu bone assay, all long-term engrafting potential and multilineage differentiation potential resided within the Rh123lo-mid but not Rh123hi subset. Furthermore, human marrow subpopulations derived from chimeric sheep after in utero transplantation with CD34+Thy-1+Lin- cells were reisolated based on Rh123 staining. Again, CD34+Lin- subsets showing Rh123lo-mid had long-term growth in culture, whereas Rh123hiCD34+Lin- cells did not. These results show that, after injection of CD34+Thy-1+Lin- cells into an in utero microenvironment, primitive CD34+ cells maintain a Rh123 phenotype that correlates with their in vitro CAFC activity. Thus, Rh123 staining is an effective way to define functional subsets of primitive hematopoietic cell populations.

[A case of infantile coronary artery bypass grafting with only left internal thoracic artery]

A 13-year-old girl performed two coronary artery bypass grafting with only left internal thoracic artery. She had no symptoms but was pointed out the abnormality in ECG (ST depression of V4 and V5) at junior high school. According to a coronary angiogram, she was diagnosed as double coronary vessels disease (a total occlusion on the proximal left anterior descending and a stenosis of 90% on the left high lateral artery). She performed sequential coronary artery bypass grafting to the left anterior descending artery and high lateral artery with only left internal thoracic artery. The anastomotic site on the left anterior descending artery showed slight thickness of the internal lumina and chronic inflammation. However they could not detect the pathological diagnosis. The postoperative course was uneventful. The postoperative angiographic control demonstrated a good patency with much blood flow of the left internal thoracic artery graft sequentially anastomosed to the left anterior descending artery and high lateral artery. The postoperative electrocardiogram became normal. She discharged on the 19th postoperative day. The sequential coronary artery bypass grafting with the left internal thoracic artery was effective for infantile ischemic heart disease.

Increased expression of cytokines in liver and serum in patients with extrahepatic diseases

To determine whether the liver plays an immunological role in certain extrahepatic disorders, we investigated the expression of interleukin (IL)-1 beta, IL-6, interferon (IFN)-gamma, and tumor necrosis factor (TNF)-alpha in 11 patients who had recovered from cholecystolithiasis, 12 patients with gastric cancer, 20 patients with chronic hepatitis, and 6 healthy controls. Cytokine mRNAs in the liver were detected by semiquantitative reverse transcribed-polymerase chain reaction. Serum cytokines and soluble IL-2 receptor (sIL-2R) were investigated by enzyme-linked immunosorbent assays. Increases in TNF-alpha, IL-6, IL-1 beta, and IFN-gamma mRNAs were found in the livers of patients with extrahepatic diseases. TNF-alpha and IL-6 peptides were increased in the sera of patients with gastric cancer. TNF-alpha in the sera and TNF-alpha mRNA in the liver were correlated in gastric cancer patients. Surprisingly, sIL-2R in the serum of gastric cancer patients was significantly higher than the level in healthy controls. Our findings suggest that the liver produces cytokines in reaction to extrahepatic lesions. Further, the increase in sIL-2R in gastric cancer patients indicates that malignancy may affect the immune network in vivo.

[Pharmacokinetics of norfloxacin and lomefloxacin in aqueous humour analysed by microdialysis]

The pharmacokinetics of norfloxacin (NFLX) and lomefloxacin (LFLX) in rabbit aqueous humour after instillation of 0.3% solution (20 microliters) and oral administration (20 mg/kg) were investigated by microdialysis. We also measured plasma concentration of fluoroquinolones after oral administration. After instillation, the maximum concentration (Cmax) of NFLX and LFLX in the aqueous humour was 0.80 and 1.20 micrograms/ml, and elimination half time (t1/2) was 130 and 96 min, respectively. After oral administration, the Cmax in plasma of NFLX and LFLX was 2.06 and 1.89 micrograms/ml, and the Cmax in aqueous humour was 0.16 and 0.62 microgram/ml, respectively. t1/2 of NFLX in aqueous humour and plasma was 225 and 295 min, and t1/2 of LFLX was 188 and 175 min, respectively. The ratio of aqueous humour/serum concentration of NFLX and LFLX was 7.8 and 35.3% 4 hrs after oral administration. These results suggest that, after instillation, LFLX penetrated better into the aqueous humour, and was eliminated faster, than NFLX, and that after oral administration, NFLX could not panetrate well into the aqueous humor from the blood.

Extracting 1/f fluctuation from the arterial blood pressure of an artificial heart

We have studied the fluctuations of an artificial circulation for the analysis of the physiological aspects; however, the conventionally used fast Fourier transform (FFT) method cannot separate harmonic oscillations, such as respiratory and Mayer waves, from the 1/f fluctuation, which has been though to represent underlying fractal dynamics. Fractal structure was shown in the strange attractor with chaotic dynamics, which is thought to be a flexible and intelligent system. In this study, the coarse-graining spectral analyzing (CGSA) method was utilized to quantitatively evaluate the proportion of the 1/f fluctuation in the total power in the frequency domain and to analyze artificial circulation in the whole system. We implanted two pneumatically actuated ventricular assist devices as biventricular bypasses (BVBs) in chronic animal experiments using 4 healthy adult goats. To compare the natural and prosthetic circulation of each experimental animal, the BVB-type complete prosthetic circulation model with electrically induced ventricular fibrillation was adopted. All hemodynamic parameters of natural and prosthetic circulation were recorded under awake conditions and calculated with the use of a personal computer. With the use of the CGSA method, time-series data of the hemodynamics were analyzed and fractal percentages, extracting the 1/f fluctuation from a given time series, were calculated. Fractal percentages of the arterial blood pressure were 85.8 +/- 10.7% and 82.0 +/- 7.3% with natural and artificial circulation, respectively (not significant [NS]). 1/f fluctuation showed the characteristics of being fractal in a time series. The fractal structure showed robustness and error resistance in nonlinear dynamics. Therefore, our results suggest that the circulatory regulatory system of the artificial heart may have desirable characteristics such as error resistance.

Spectral analysis of hemodynamics during left ventricular assistance

In order to analyze the autonomic nervous system during left ventricular (LV) assistance, fluctuations in hemodynamic derivatives were evaluated by a spectral analyzing method using a fast fourier transform (FFT) methodology. After the left pleural cavity was opened through the fourth intercostal space under general anesthesia, a pneumatically driven ventricular assist system was implanted as in left heart bypasses in chronic animal experiments, using three healthy adult goats. Hemodynamic parameters with and without LV assistance were recorded on a magnetic tape in the awake condition then analyzed in a computer system through an A-D convertor. Power spectral analysis was performed on a beat-to-beat basis for the evaluation of the fluctuations. During copulsation mode LV assistance, Mayer wave fluctuations (0.1 Hz) were significantly increased compared with counterpulsation mode LV assist, suggesting an increase in sympathetic tone. Co-pulsation mode LV assist is reported to increase the afterload of the natural left ventricle, thus, the sympathetic tone may be increased to maintain a natural heart output.

Searching for hematopoietic stem cells. II. The heterogeneity of Thy-1.1(lo)Lin(-/lo)Sca-1+ mouse hematopoietic stem cells separated by counterflow centrifugal elutriation

Mouse hematopoietic stem cells (HSCs) are highly enriched in the rare (approximately 0.05%) Thy-1.1(lo)Lin(-/lo)Sca-1+ fraction of hematopoietic tissues. It has been demonstrated that Thy-1.1(lo)Lin(-/lo)Sca-1+ cells are the only HSCs in C57BL/Ka-Thy-1.1 bone marrow. In this study, we separated C57/Ka-Thy-1.1 bone marrow cells by counterflow centrifugal elutriation (CCE) into four fractions and characterized Thy-1.1(lo)Lin(-/lo)Sca-1+ cells in each eluted fraction. The peak number of Thy-1.1(lo)Lin(-/lo)Sca-1+ cells was highly enriched in one eluted fraction, which was also highly enriched for day-12 to -13 CFU-S. Activities for day-13 CFU-S, radioprotection, and long-term multilineage reconstitution correlated with, and could be generally predicted by determining, the frequency of Thy-1.1(lo)Lin(-/lo)Sca-1+ cells in a given eluted fraction. However, the fraction that was highly enriched for blast cells and contained a low frequency of Thy-1.1(lo)Lin(-/lo)Sca-1+ cells, only provided short-term but not long-term radioprotection, with a predicted cell number (100 cells) that should have protected > or = 95% (PD95) of hosts. Still, when 300 Thy-1.1(lo)Lin(-/lo)Sca-1+ cells from this fraction (3 X PD95 for unfractionated HSCs) were injected, mice were radioprotected and donor cells provided long-term multilineage reconstitution. We propose that such blast cells may contain two Thy-1.1(lo)Lin(-/lo)Sca-1+ subsets, one providing short-term and the other long-term multilineage sustained hematopoiesis, the latter presumably due to HSC self-renewal.

Scanning of polypoid gallbladder lesions by ultrasonic microprobes using transpapillary catheterization

BACKGROUND AND STUDY AIMS

Polypoid lesions of the gallbladder can be diagnosed by transabdominal ultrasonography and endoscopic ultrasonography. However, the image resolution is limited, and the histopathology of these lesions is difficult to determine. We report here on our preliminary results in four patients using a high-frequency (20 MHz) ultrasonic microprobe introduced into the gallbladder via the transpapillary approach.

PATIENTS AND METHODS

Insertion of the microprobe into the gallbladder through the papilla of Vater was attempted in four patients with gallbladder diseases without preceding endoscopic sphincterotomy.

RESULTS

The lesions in the gallbladder were clearly visualized in three of the four patients. We tried to correlate the characteristic ultrasound findings with the histopathology of the lesions, which were found to be early cancer, adenoma, and adenomyomatosis on histopathology of the specimens after cholecystectomy. No complications occurred.

CONCLUSIONS

High-resolution endoscopic transpapillary ultrasonography of the gallbladder is feasible and safe, and may contribute to the diagnosis of gallbladder diseases, particularly of small polypoid lesions.

Changes in viscoelasticity of the myocardium during cardioplegic arrest

To evaluate the efficacy of myocardial preservation during open heart surgery, we measured the viscoelasticity of the canine myocardium during cardioplegic arrest. A transfer function method was used for the measurement with a monitoring system consisting of a vibrator, a function generator, accerometers and a signal processor. Six mongrel dogs were put on cardiopulmonary bypass and after measurement of control hemodynamics, they were subjected to cardioplegic arrest at myocardial temperatures ranging from 4 to 32 degrees C. Viscoelasticity was measured at every 15 min and the cardioplegic solution was added every 30 min. After two hr of cardioplegic arrest, the myocardium was reperfused and postischemic hemodynamics were measured after 30 min of non-working beating. Satisfactory myocardial function returned in 3 hearts with the myocardial temperatures below 24 degrees C with myocardial viscoelasticity within the control range. Moderately decreased myocardial contractility was noted in a heart kept at temperature of 27 degrees C and its viscoelasticity remained in the control range of 90 min of ischemia and then began to decrease. In 2 hearts kept at temperatures higher than 29 degrees C, severely depressed myocardial contractility was noted, and viscoelasticity decreased transiently at 45 to 60 min and then returned to control levels. These results suggested usefulness of continuous monitoring of the viscoelasticity in early detection of its degenerative alterations due to impaired myocardial preservation during open heart surgery.

Effects of UVC irradiation on cultured mouse embryonic limb bud cells

Effects of UVC irradiation (UVC) at a dose range from 0 to 30 J/m(2) were investigated on the cultured embryonic limb bud cells (LBC), isolated from fore- and hindlimbs of day 11 mouse embryos. Although dose-dependent inhibition was found for both cellular proliferation and chondrogenesis, the chondrogenic proteoglycan (PG) synthesis was more sensitive to UVC than cellular proliferation when compared at ID(50), the inhibitory dose that reduced assessment value by 50% of the control. No significant difference in induction and repair kinetics of UV-induced cyclobutane pyrimidine dimers (CPDs) and (6-4) photoproducts ((6-4)PPs) were found between LBC and NIH3T3 mouse cell line. The fluorescent light (FL) treatment of LBC pre or post UVC irradiation did not affect repair kinetics of CPDs and (6-4)PPs, cellular proliferation, formation of PG-producing nodule and the PG synthesis.

[Evaluation of inferior epigastric arterial graft from the aspect of angiography]

We evaluated inferior epigastric artery (IEA) from the aspect of preoperative and postoperative grafts angiography. Between January 1994 and february 1995, we could perform preoperative and postoperative graft-angiography for 12 patients in 27 patients who were undergone CABG using IEA graft. They were 7 males and 5 females. The age ranged from 56 to 76 years (mean, 66.2 years). We used 12 IEAs, 8 LITAs, 7 RGEAs and 2 RITAs as artrial grafts. We measured the diameter of arterial grafts in each angiography. The preoperative diameter of IEA was measured at three points; the proximal part (Prox), center (Cent) and bifurcation (Bif). The postoperative diameter of IEA was measured at two points; the proximal part of composite graft (Prox) and the distal part (Dist). The preoperative grafts diameters were IEA-Prox = 2.01 +/- 0.40 mm, IEA-Cent = 1.75 +/- 0.39 mm, IEA-Bif = 1.32 +/- 0.29 mm, LITA-Prox = 2.40 +/- 0.25 mm, LITA-Cent = 2.00 +/- 0.24 mm, LITA-Bif = 1.64 +/- 0.22 mm, RGEA-Prox = 2.72 +/- 0.49 mm, and RGEA-Cent = 2.29 +/- 0.34 mm. RGEA was the largest, the second was RITA, the third was LITA and IEA was the smallest of the four. The diameter of IEA-Prox was almost equal to LITA-Cent. The postoperative grafts diameter were IEA-Prox = 1.85 +/- 0.37 mm, IEA-Dist = 1.67 +/- 0.38 mm, LITA-Prox 2.57 +/- 0.11 mm, LITA-before Y = 2.01 +/- 0.22 mm, LITA-after Y = 1.83 +/- 0.14 mm, RGEA-Prox = 2.70 +/- 0.55 mm and RGEA-Dist = 0.53 mm. RGEA was the largest and RGEA-Dist = 2.34 +/- 0.53 mm. RGEA was the largest and IEA was the smallest. The diameter of LITA was not significantly different between before-Y and after-Y. We conclude in view of the graft diameter, LITA-IEA Y composite graft is the best method for CABG using IEA but IEA graft should be used only to myocardial revascularization to the coronary lesion that does not require high blood flow.

Development of a clinically applicable high-speed flow cytometer for the isolation of transplantable human hematopoietic stem cells

A high-speed cell sorter capable of a throughput speed 4-5-fold greater than commercially available systems was developed and evaluated as a processing tool for isolating purified hematopoietic stem cell grafts. The clinical high-speed sorter (CHSS) serves as a single-pass, multiparameter processing tool that provides the means to isolate a highly purified population of cells from starting cell populations with extremely low frequencies. The sorter incorporates environmental barriers to create a sterile environment for cell processing. Monoclonal antibodies and reagents produced under good manufacturing practices (GMP) are used to isolate hematopoietic stem cells by means of the CHSS. Using this technology, the CD34+Thy-1+Lin- hematopoietic stem cell population has been isolated from normal adult bone marrow and mobilized peripheral blood. The sorted cells have been shown to be sterile and viable and to retain hematopoietic function.

Papillary dilation vs sphincterotomy in endoscopic removal of bile duct stones. A randomized trial with manometric function

To circumvent the long-term effects of papillary ablation for extracting common bile duct stones (< 12 mm in diameter) in endoscopic sphincterotomy (EST), endoscopic papillary dilation (EPD) was attempted in 20 patients. To evaluate papillary function before and after the procedures, manometry of the sphincter of Oddi was carried out in 13 with EPD and 10 of 20 patients with EST. Extraction of all stones was successful (100%) in both groups at an equal rate. Repeated numbers of procedures were common in both groups. However, the mean duration of the procedure was high in EPD compared to EST (63 min vs 42 min, P < NS). Adjunctive therapies like mechanical lithotripsy (ML), nasobiliary drainage, and choledochoscopy were included in EPD, while EST required a basket catheter and ML. There was no significant difference on manometry before and after the procedures (P = NS), although papillary function was found to have decreased after the EPD. In contrast, all patients in the EST group lost papillary function after the procedure. Thirty-day morbidity and mortality rate were absent in both groups. Immediate and 2.5-year follow up complications were uncommon in both groups. As a simple method, EPD may be an effective and safe alternative to EST in the management of patients with bile duct stones who require maintenance of papillary function.

The biology of hematopoietic stem cells

Hematopoietic stem cells (HSC) are the only cells in the blood-forming tissues that can give rise to all blood cell types and that can self-renew to produce more HSC. In mouse and human, HSC represent up to 0.05% of cells in the bone marrow. HSC are almost entirely responsible for the radioprotective and short- and long-term reconstituting effects observed after bone marrow transplantation. The subsets of HSC that give rise to short-term vs long-term multilineage reconstitution can be separated by phenotype, demonstrating that the fates of HSC are intrinsically determined. Here we review the ontogeny and biology of HSC, their expression of fate-determining genes, and the clinical importance of HSC for transplantation and gene therapy.

Cytokine-mobilized peripheral blood CD34+Thy-1+Lin- human hematopoietic stem cells as target cells for transplantation-based gene therapy

Gene-therapy of blood-borne disorders may be best achieved using hematopoietic stem cells (HSC) which have extensive self renewal potential as well as multilineage repopulating potential as a cellular target. The human HSC, which is CD34+Thy-1+Lin- has been isolated from fetal, adult bone marrow and cytokine-mobilized peripheral blood (MPB) (1-3). Results presented in this study show that the degree of mobilization of HSC into peripheral blood of cancer patients is highly variable and that the combined use of high dose chemotherapy and GM-CSF as a mobilization strategy is superior to the use of G-CSF with regard to the mobilization of true HSC. A multistep cell isolation procedure has been developed which utilizes high speed flow-cytometric cell sorting and allows the isolation of sufficient numbers of HSC from MPB to permit their use as an hematopoietic graft for clinical transplantation. Hematopoietic stem cells isolated from MPB are capable of self-renewal and differentiation into multiple hematopoietic lineages as shown by their behavior in both in vitro and in vivo assays. Mobilized PB mononuclear cells isolated from cancer patients are frequently contaminated with tumor cells. Using this cell isolation procedure, HSC preparations from patients with multiple myeloma have been created with greatly reduced tumor cell burdens. These CD34+Thy-1+Lin- cells are capable of being stably transduced at high efficiency (32-75%) by co-culture on a cell line producing recombinant retroviruses containing the neomycin-resistant gene. These HSC cell populations are likely ideal targets for hematopoietic cell-based gene therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

[Endoscopic lithotomy using sublingual nitroglycerin]

After medical sphincter dilation using sud-lingual nitroglycerin, endoscopic removal of common bile duct stones in 15 patients was carried out. Complete stone removal was obtained in 14 of 15 patients. Only 0.3 mg to 0.6 mg nitroglycerin was needed to give an enough dilation of the orifice for cannulating the basket catheter into the bile duct. Mechanical lithotriptor was smoothly cannulated in one patient because of possible impaction. Blood pressure was dropped transiently in one patient by nitroglycerin, however, the general condition of the patient was stable. This procedure is safe, easy and effective in preserving sphincter function. Acute cholecystitis, a common complication of persistent gallbladder stone after endoscopic sphincterotomy, may be avoided by employing this method. More clinical studies, on long term and in a large scale of patients, are necessary to reduce complications that usually occur after sphincterotomy.

[Y-grafting using the inferior epigastric artery for coronary revascularization]

On view of the remarkable good results obtained with arterial grafts for coronary revascularization, the authors continue to conduct the total arterial bypass grafting. However, the following disadvantages are encountered; 1) arterial graft crossing over the aorta and 2) left internal thoracic artery (LITA) is on some occasions impossible to anastomose with the left anterior descending (LAD) coronary artery. To eliminate these problems, "IEA Y-grafting" which the IEA is anastomosed with the LITA in an end-to-side fashion was conducted. From January to December 1994, 24 patients underwent coronary revascularization by this method. All 24 IEA grafts were anastomosed to the circumflex coronary artery (22), right coronary artery (3) or diagonal branch. (1). LITA graft were used on 24 patients (29 anastomosis) with the right gastro-epiploic artery (RGEA) at 16 (17) and RITA at 2. Immediate postoperative angiographic evaluation of the IEA grafts indicated 17 anastomoses to be patent (17/19, 89.5%). Two patients died due to coronary spasm. Although hypoperfusion poses a serious problem in this method, IEA may be considered to serve as a 3rd alternative for an arterial conduit.

[Coronary revascularization with arterial graft alone by normothermic cardiopulmonary bypass and warm blood cardioplegia]

We studied the effects of Calafiore technique that is intermittent (every 15 minutes) antegrade warm blood cardioplegia oxygenated and included high potassium solution with normothermic cardiopulmonary bypass. From September 1994 to February 1995, 20 patients having continuously elective coronary artery bypass grafting with arterial conduits alone were randomized to traditional intermittent cold crystalloid cardioplegia and slight hypothermic cardiopulmonary bypass (cold group) or warm heart surgery by Calafiore technique (warm group). Preoperative variables were similar to both groups, as were the intraoperative variables of number of coronary grafts, aortic cross-clamp time, and cardiopulmonary bypass time. Warm group had more rapidly spontaneous defibrillation at cross-clamp removal than cold group. CK on one postoperative day was lower than cold group. Warm group had good results as concern postoperative blood loss volume, intubated time, and change of base excess. Events of PMI (cold, 2 and warm, 0) and need of an intraaortic balloon pump (cold, 2 and warm, 0) were significantly lower in the warm group. We suspected the possibility of vasospasm was lower in the warm group. We concluded warm heart surgery (Calafiore technique) was a best technique for CABG with arterial conduits.

[Dislodgement of the ringed-graft--a case report]

A 70-year-old man underwent replacement of the distal aortic arch which contained a huge aneurysm using a ringed graft. He died suddenly of hemoptysis 54 months following the operation. An autopsy revealed dislodgement of the spool on the posterior aspect of the aorta. Histologic examination of the dislodged portion of the ring showed complete disruption of the intima and elastic fibers of the media. There were minimal histologic changes in the anterior portion of the anastomotic site. It is postulated that the long, kinked graft might have caused the late ring dislodgement.

Changes of hepatic microsomal oxidative drug metabolizing enzymes in chronic renal failure (CRF) rats by partial nephrectomy

Male SD rats, 7-weeks-old, were used to investigate the changes in the hepatic drug metabolizing system of chronic renal failure (CRF) model rats. Partial nephrectomy (5/6) was performed in a two-stage surgical procedure. After nephrectomy, the rats were housed under regular conditions at least 21 days. After confirming the CRF states, trimethadione (TMO, 100 mg/kg, i.p.) was administered for evaluation of the hepatic drug metabolizing capacity; the ratio of dimethadione (DMO: the only metabolite of TMO) to TMO (DMO/TMO) in the serum and the dialysate from the blood microdialysis method were ascertained. The hepatic drug metabolizing enzyme contents and activities were also determined. In the CRF rats, the DMO/TMO ratios decreased significantly; total cytochrome P450 (CYP) contents, aminopyrine N-demethylase activity and delta-aminolevulinic acid synthetase activity also decreased significantly in the CRF rats. The extent of the alterations of these enzyme contents and activities correlated well with the severity of the CRF states evaluated by the serum blood urea nitrogen and creatinine concentrations. With Western blot analysis, the levels of CYP2C6, CYP2C11 and CYP3A2 decreased considerably in the CRF rats. These results suggest that CRF states induce not only a reduction of renal function but also an alteration of hepatic metabolism.