Angioarrestin mRNA expression in early-stage lung cancers

AIMS

Angioarrestin is a recently isolated gene, which has a novel function as an angiogenesis inhibitor. Angiogenesis plays an important role in tumorigenesis. It has been reported that the angioarrestin expression was decreased in lung cancer. We attempted to determine the influence of angioarrestin expression on clinicopathological features in patients with lung cancer who had undergone surgery.

METHODS

Expression of angioarrestin messenger RNA was evaluated by a quantitative reverse transcription-polymerase chain reaction (RT-PCR) in 93 lung carcinomas and adjacent histological normal lung samples using LightCycler.

RESULTS

Angioarrestin/GAPDH mRNA expression was significantly decreased in the tumor of lung cancer tissue (86.676+/-123.505) than in the normal lung tissue (1154.218+/-2003.508, p<0.0001), although only four lung cancer tissues had more than one tumor/normal ratio of angioarrestin/GAPDH mRNA expression. There was no relationship between angioarrestin gene expression and age, gender or T-status. However, decreased angioarrestin/GAPDH expression was especially seen at stage I lung cancer (54.156+/-62.783) when compared to stage II-IV lung cancer (110.315+/-151.359, p=0.0316). Decreased angioarrestin/GAPDH expression was especially seen at N0 lung cancer (56.396+/-69.941) when compared to N2 lung cancer (137.522+/-180.489, p=0.0362).

CONCLUSIONS

The decreased expression of angioarrestin mRNA was the early phase phenomena for tumor progression from lung cancer. Alternatively, loss of antianiogenesis might play a role in oncogenesis for lung cancer.

[Therapeutic options which potentially cure patients with thymoma]

This study reports clinicopathologic features, treatment, and outcome of 107 thymomas, especially focusing on a combined modality program using hemithorax irradiation (HI) and restaging surgery using corticosteroid for advanced thymoma showing disseminative lesions. The use of HI after presumably total resection of the dissemination under posterolateral thoracotomy had no effect on reducing the incidence of relapsing. On the other hand, our own experience revealed that corticosteroid caused degenerative changes in the epithelial cells and lymphocytes of thymomas. The fact led us administer corticosteroid not only in preoperative setting but during postoperative HI. A better prognosis may be anticipated, although the follow up period is short and the number of patients involved is small.

Massive large bowel resection decreases bone strength and magnesium content but not calcium content of the femur in rats

We examined the effects of massive large bowel resection (cecocolonectomy) on calcium and magnesium absorption and bone characteristics in rats. Male Sprague-Dawley rats were divided into two groups: sham-operated and cecocolonectomized rats. The rats were fed a sucrose-based diet containing casein at 250 g/kg diet for 10 d after a 9- to 10-d postoperative recovery period. Apparent magnesium absorption but not calcium absorption was lower in the resection group than in the sham group. There was a tendency of lower serum magnesium concentration (P = 0.070) but not calcium concentration (P = 0.418) in the resection group compared with the sham group. The maximum breaking force and magnesium content but not the calcium content of the femur were lower in the resection group than in the sham group. These results suggest that massive large bowel resection influences magnesium kinetics and decreases bone strength through reduction of the magnesium content of the femur in rats. Femoral breaking force was positively correlated (r = 0.617, P = 0.011) with only the magnesium content. We conclude that the changes in magnesium kinetics caused by cecocolonectomy could contribute to the fragility of bone.

SNRK, a member of the SNF1 family, is related to low K(+)-induced apoptosis of cultured rat cerebellar granule neurons

When cerebellar granule neurons obtained from 11-day-old rats were cultured first in high K(+) medium for 4 days, followed by culture in low K(+) medium, the neurons underwent apoptosis and died. This cell death was prevented by actinomycin D, an inhibitor of RNA synthesis. Commitment time of the protective effect of RNA synthesis inhibition on the cell death was examined by adding actinomycin D at various time points after the switch to the low K(+) medium. More than 50% of the cells died when actinomycin D was added 3 h after changing to the low K(+) medium. To identify what kinds of newly synthesized genes are involved in regulation of the low K(+)-induced death, we performed PCR-based differential subtraction analysis using RNA prepared from the cultured neurons 0 and 3 h after changing to low K(+) medium. We isolated a clone that showed an increase in its mRNA level after changing to the low K(+) medium. This clone encoded the 3' untranslated region of SNRK, a serine/threonine kinase. Tissue distribution analysis showed that the mRNA was expressed mainly in the brain and testis. Developmental analysis in the brain showed that the mRNA expression increased in an age-dependent manner until P28, and was slightly decreased in adults. In situ hybridization analysis showed that the mRNA was expressed throughout the brain. The mRNA was shown to be expressed in neurons by double staining with anti-MAP2 antibody. In addition, anti-N-terminal SNRK antibody stained the nuclei of cultured rat cerebellar granule neurons. These results suggested that SNRK may be involved in regulation of low K(+)-induced apoptosis of cultured cerebellar granule neurons.

BH4 domain of antiapoptotic Bcl-2 family members closes voltage-dependent anion channel and inhibits apoptotic mitochondrial changes and cell death

A change of mitochondrial membrane permeability is essential for apoptosis, leading to translocation of apoptogenic cytochrome c and apoptosis-inducing factor into the cytoplasm. We recently showed that the Bcl-2 family of proteins regulate cytochrome c release and the mitochondrial membrane potential (Deltapsi) by directly modulating the activity of the voltage-dependent anion channel (VDAC) through binding. Here we investigated the biochemical role of the conserved N-terminal homology domain (BH4) of Bcl-x(L), which has been shown to be essential for inhibition of apoptosis, with respect to the regulation of mitochondrial membrane permeability and found that BH4 was required for Bcl-x(L) to prevent cytochrome c release and Deltapsi loss. A study using VDAC liposomes revealed that Bcl-x(L), but not Bcl-x(L) lacking the BH4 domain, inhibited VDAC activity. Furthermore, BH4 oligopeptides of Bcl-2 and Bcl-x(L), but not mutant peptides, were able to inhibit both VDAC activity on liposomes even in the presence of Bax and apoptotic Deltapsi loss in isolated mitochondria. It was also shown that the BH4 domain, fused to the protein transduction domain of HIV TAT protein (TAT-BH4), efficiently prevented apoptotic cell death. These results indicate that the BH4 of Bcl-2/Bcl-x(L) is essential and sufficient for inhibiting VDAC activity, which in turn prevents apoptotic mitochondrial changes, and for preventing apoptotic cell death. Finally, the data suggest that the TAT-BH4 peptide is potentially useful as a therapeutic agent for diseases caused by accelerated apoptosis.

Efficient production of N-terminally truncated biologically active human interleukin-6 by Bacillus brevis

cDNAs encoding human interleukin 6 (hIL-6) and its variants lacking the N-terminal Pro and Pro-Val-Pro-Pro, respectively, were expressed in Bacillus brevis by using the signal peptide fusion approach. The presence of Pro at the N-terminus of the mature protein hindered the action of the Bacillus brevis signal peptidase. hIL-6 lacking the N-terminal Pro-Val-Pro-Pro was most efficiently secreted in a biologically active form and accumulated in the culture medium to a level of 200 mg per liter, which is the highest level reported for the bacterial secretion of hIL-6.

Contribution of the cecum and colon to zinc absorption in rats

We examined the role of the large intestine in zinc absorption in rats in three separate experiments. In the first experiment, we examined apparent zinc absorption in rats fed diets containing graded levels of zinc carbonate (0.015-0.535 mmol Zn/kg diet) and evaluated zinc status on the basis of the zinc concentrations in serum and several tissues. The zinc absorption and the serum zinc concentration increased with the zinc content of the diet up to 0. 153 mmol Zn/kg diet. Femoral and pancreatic zinc levels increased linearly up to 0.229 mmol Zn/kg diet. In the second experiment, a zinc carbonate suspension was administered into the cecum via an implanted cannula or into the stomach via an orogastric tube, and the rats were fed diets with or without a highly fermentable fiber, guar gum hydrolysate (GGH, 50 g/kg diet), with coprophagy prevention. The amount of instilled zinc corresponded to the amount of zinc ingested as a component of the diet by the rats of a control group, 0.229 mmol Zn/kg diet. Apparent absorption of cecally instilled zinc was approximately half that observed when zinc was administered into the stomach in both diet groups. Serum and femur zinc concentrations in the cecum-administered groups were approximately 50 and 25% lower, respectively, than those in rats administered zinc into the stomach. The results demonstrate that, in vivo, the absorptive efficiency in the large intestine is not sufficient to satisfy the rat's zinc requirement and does not change when the luminal environment is substantially altered by feeding GGH. In Experiment 3, the effects of cecocolonectomy on zinc absorption were examined in rats with gastric acid suppression. In the cecocolonectomized groups, serum zinc concentration was lower as a result of treatment with a proton pump inhibitor, omeprazole, than in vehicle-treated rats, but not in sham-operated groups. These findings suggest that the cecum and colon contribute to zinc absorption when absorption in the small intestine is impaired.

Overexpression of cation-dependent mannose 6-phosphate receptor prevents cell death induced by serum deprivation in PC12 cells

PC12 cells express well cation-independent mannose 6-phosphate receptors (CI-MPR), but not cation-dependent (CD)-MPR as much. To examine CD-MPR dependency of transport of cathepsins B and D to lysosomes in PC12 cells, we prepared the cells overexpressing CD-MPR. Immunoreactivity for cathepsin B became more distinct and larger in size in the transfected cells than in wild-type cells. No difference in the distribution of cathepsin D was seen between these two cells. The viability of the cells following serum deprivation was significantly higher in the transfected cells than in wild-type cells. This increased viability of the transfected cells was blocked by CA074, a specific inhibitor of cathepsin B, while pepstatin A suppressed the action of CA074. The results suggest that CD-MPR preferentially transport cathepsin B in PC12 cells, and cathepsins B and D participate in the regulation of PC12 cell apoptosis.

Participation of cathepsins B and D in apoptosis of PC12 cells following serum deprivation

Cathepsin D, a lysosomal aspartic proteinase, has been shown to induce apoptosis of HeLa cells when overexpressed. To further understand regulatory mechanisms of cathepsin D-induced cell death, we examined whether lysosomal cysteine and aspartic proteinases are involved in apoptosis of PC12 cells following serum deprivation. In serum deprived culture, PC12 cells overexpressing cathepsin D died more rapidly than wild-type cells. When the active forms of cathepsins B and D were examined during the apoptotic process of wild-type cells, the amount of cathepsin B was drastically reduced 24 hr after the onset of culture, whereas that of cathepsin D considerably increased. The viability of PC12 cells overexpressing cathepsin B was significantly higher in serum-deprived culture than wild-type cells. In this situation, the amount of the cathepsin B protein did not decrease. The results suggest that there exists an apoptotic pathway regulated by lysosomal cathepsins B and D.

[Determination of the distance between the upper incisors and the laryngoscope blade during laryngoscopy: comparisons of the McCoy, the Macintosh, the Miller, and the Belscope blades]

We compared the distance between the upper central incisors and the laryngoscope blade with the four different types of laryngoscope blade (McCoy, Macintosh, Miller, Belscope). Twenty-three patients scheduled for general anesthesia were studied. The tooth-blade distance was measured when optimum visibility of the glottis was obtained. The visibility was determined according to the Cormack and Lehane grading. The distance with the McCoy and the Belscope was greater than that with the Macintosh or the Miller. The visibility grade was significantly worse with the Macintosh than with the other types of laryngoscope. The results indicate that the McCoy and the Belscope provide less incidence of upper dental injuries and greater visibility than either with the Macintosh or the Miller. Furthermore, the force applied to the handle is thought to be smaller with the McCoy than with the Belscope.

[A comparison of the grade of laryngeal visualisation;--the McCoy compared with the Macintosh and the Miller blade in adults]

Effectiveness in visualization of the vocal cord during orotracheal intubation with McCoy (McC) compared with Macintosh (Min) and Miller (Mil) blades were investigated. After an institutional review board approval, 117 patients for elective surgery under general anesthesia requiring tracheal intubation were investigated. Five board certified anesthesiologists tried to visualize the vocal cord of a patient three times with the three different types of laryngoscope. Total of 351 intubation attempts were studied. The view obtained at laryngoscopy with each of the three blades was recorded as follows. Grade 1. If most of the glottis is visible. Grade 2. If only the posterior extremity of the glottis is visible. Grade 3. If no part of the glottis can be seen. Grade 4. If not even the epiglottis can be exposed. Eight-two Grade 1 views were obtained with McC, 72 with Mil and 47 with Min, respectively. Thirty-three Grade 2 views were obtained with McC, 36 with Min and 24 with Mil. Two Grade 3 views with McC, 34 with Min and 14 with Mil were obtained. Seven Grade 4 views were obtained with Mil. The grades of laryngeal visualization with McC were significantly lower than those with Min and Mil.

[Cervival spine movement during light-guided orotracheal intubation with lightwand stylet (Trachlight)]

We assessed the degree of movement of the cervical spine (C-spine) during light-guided orotracheal intubation using a lightwand stylet (Trachlight). Twenty ASA 1-2 patients were studied. Following induction of anesthesia and obtaining muscle relaxation, the cross-table lateral radiograph of C-spine was taken before and during the intubation with Trachlight. We measured the distance between the spinous processes of C1 and the occiput (delta C1-occiput), and the degree of displacement of C1 and C5 against C3 (delta C1 + C5) by tracing the standard and intubation films. The results showed that delta C1-occiput was larger and delta C1 + C5 was smaller with Trachlight than with conventional or McCoy laryngoscopy we had previously reported. We concluded that light-guided intubation technique using Trachlight needed less movement of the C-spine in contrast to direct laryngoscopy. We believe that Trachlight is an easy, alternative and beneficial device for patients in whom cervical spine movement is limited or undesirable.

A new method for studying the binding of human IgE to CD23 and the inhibition of this binding

CD23, a low-affinity receptor for IgE (Fc epsilonRII), is a type II membrane-bound glycoprotein expressed on many hematopoietic cells, particularly activated B-cells. CD23 binds to IgE at a domain homologous to Ca2+-dependent (C-type) animal lectin. This paper describes a binding assay by which only the specific binding of IgE to CD23 expressed on Epstein-Barr virus (EBV)-transformed B-cell line, L-KT9 cells, can be detected. This assay is useful in the search for CD23 ligands among many chemical compounds, because it is easily carried out and does not require the use of any radiolabeled reagents. Using the assay, we investigated the inhibition of IgE binding to CD23 by fucose-1-phosphate which has been reported to inhibit the binding of sCD23 to IgE [Delespesse, G., Sarfati, M., Wu, C.Y., Fournier, S., Letellier, M., 1992. The low affinity receptor for IgE. Immunol. Rev. 125, 77.] and the binding of CD23 to CD21 [Pochon, S., Graber, P., Yeager, M., Jansen, K., Bernard, A.R., Aubry, T.-P., Bonnefoy, J.-Y., 1992. Demonstration of second ligand for the low affinity receptor for immunoglobulin E (CD23) using recombinant CD23 reconstituted into flourescent liposomes. J. Exp. Med. 176, 389.]. Although both alpha- and beta-L-fucose-l-phosphate/di(cyclohexylammonium) salt decreased the extent of IgE binding to CD23, the inhibitory effects were not due to alpha- or beta-L-fucose-1-phosphate but to cyclohexylamine. The inhibitory effect of cyclohexylamine was dose dependent and the effect was decreased when inhibition tests were carried out in the presence of a 10-fold excess of IgE. These results suggest that cyclohexylamine specifically interacts with the binding of CD23 and IgE.

[Which laryngoscope is the most stressful in laryngoscopy; Macintosh, Miller, or McCoy?]

Stress responses during laryngoscopy were compared among the situations using three different laryngoscopes, Macintosh (curved standard blade), Miller (straight blade), or McCoy (levering). Blood pressure, heart rate (in 58 patients) and plasma concentration of catecholamines (in 29 patients) were measured before, during and after laryngoscopy without tracheal intubation. Systolic blood pressure after laryngoscopy was significantly higher in the Miller group than in other two groups. Plasma epinephrine concentrations after laryngoscopy in the McCoy group were lower than other two groups. Heart rate and plasma norepinephrine concentration were not different among the three groups. These results suggest that the stress response during laryngoscopy without intubation is the biggest in using the Miller laryngoscope and the smallest in using the McCoy laryngoscope.

[Assessment of the practice of endotracheal intubation by levering Laryngoscope in teaching of undergraduate medical students]

Twenty-nine inexperienced medical students tried to intubate endotracheal tubes using both levering laryngoscope (McCoy laryngoscope) and Macintosh laryngoscope in adult mannikin the Cormack and Lehane Grade 2. The number of successful intubations by McCoy type was close to those by Macintosh type. Improvement in time necessary from insertion of the laryngoscope to confirmation of placement of the endotracheal tube McCoy type was also close to that by Macintosh type. But the grade of handling difficulty of McCoy type was significantly higher than that of Macintosh type, because Macintosh type was simpler to handle than McCoy type. It was suggested that Macintosh laryngoscope was more useful than McCoy laryngoscope for teaching of inexperienced medical students.

[Systemic oxygen demand and supply balance during warm heart surgery without blood transfusion]

We investigated systemic oxygen demand and supply balance during warm heart surgery without blood transfusion on 203 patients. The patients aged 63-years on average, for coronary artery bypass surgery, were assigned to extracorporeal circulation (ECC) with flow index of either 2.4 l.min-1.m-2 or 2.6. Hemoglobin concentration (Hb), mixed venous oxygen saturation (SvO2), cardiac index (CI), oxygen delivery (DO2), oxygen consumption (VO2) and oxygen extraction ratio (OER) were determined. The mean operation time was 314 min, and the mean ECC time was 94 min. In both groups, the initiation of ECC decreased Hb to 6.5 g.dl-1, and SVO2 decreased gradually during ECC. In addition, DO2 was lower than the pre-ECC level, which may indicate the shortage of oxygen supply, while VO2 and OER increased during ECC. OER increased by 0.38 in the group with flow index of 2.4, which is higher than 0.35 of the group with 2.6. The discontinuation of ECC improved oxygen profile, mainly due to the increase of Hb and CI. These findings indicate that oxygen demand and supply balance was maintained during normothermic ECC without transfusion, although longer duration o ECC may cause the shortage of oxygen supply. A higher flow may be required during normothermic ECC.

[Cervical spine movement during orotracheal intubation using the McCoy laryngoscope compared with the Macintosh and the Miller laryngoscopes]

The movement of cervical spine during orotracheal intubation was compared using the McCoy, Macintosh or Miller laryngoscope blade. Twenty ASA 1-2 patients requiring tracheal intubation were studied. Following induction of anesthesia and obtaining muscle relaxation, the cross-table lateral X-ray was taken before and during laryngoscopy using three types of laryngoscopes. Degree of cervical spine movement was evaluated by measuring the distance between the spinous processes of C1 and the occiput, and the amount of displacement of C1 and C5 against C3 by tracing on each films. The results indicated that delta C1-occiput was larger and delta C1 + C5 smaller with the McCoy laryngoscope compared with the others. The use of the McCoy laryngoscope results in less cervical spine movement during laryngoscopy and therefore should be of particular benefit in the presence of cervical spine instability as well as in the normal patients.

Inflammatory changes after extradural anaesthesia may affect the spread of local anaesthetic within the extradural space

We have assessed cephalad spread of analgesia in 491 patients undergoing extradural anaesthesia at the L2-3 or L3-4 interspace. Patients were classified into one of three groups based on the number of previous lumbar extradural anaesthesia procedures: none (group I, n = 339), one (group II, n = 82), and two or more (group III, n = 70). Cephalad spread of analgesia was greater in group I than in groups II and III, regardless of the puncture site. In addition, we examined the extradural space using a flexible extraduroscope in 32 patients who were excluded from the analysis of spread. Extraduroscopy showed the extradural space to be patent in patients with no history of prior lumbar extradural anesthesia, but it was not clearly identified in patients who had received extradural anaesthesia one or more times because of aseptic inflammatory changes, including proliferation of connective tissue, adhesions between the dura mater and the ligamentum flavum, granulation and changes in the ligamentum flavum. Extradural anaesthesia may cause aseptic inflammatory changes in the extradural space which may reduce the spread of analgesia.

[Clinical effects of urokinase and sodium ozagrel in patients with acute symptomatic lacunar infarction]

The clinical effects were compared between a thrombolytic agent (urokinase) and a thromboxane synthetase inhibitor (sodium ozagrel) in patients with acute lacunar infarction. All patients had some degree of neurological deficits, which corresponded to the lesions on computerized tomography or magnetic resonance imaging. Urokinase of 420,000 units was given over two days in 11 patients, 160 mg/day of sodium ozagrel was administered for two weeks in 23 patients. The study was followed up to one month after the onset. Urokinase treatment improved motor paresis in 45.5-62.5% of the patients, sodium ozagrel in 68.4-86.7%. Using the combined score of motor paresis and conscious disorder, urokinase group revealed 44.4-45.5% improvement, but sodium ozagrel group 81.0-89.5% (p < 0.05). The rates of suppressive effect in progressing stroke and complete recovery were higher in sodium ozagrel group. Sodium ozagrel was clinically more efficient than urokinase in patients with lacunar infarction.

Interleukin-6 and granulocyte colony-stimulating factor synergistically increase peripheral blood progenitor cells in myelosuppressive mice

We previously reported a successful peripheral blood stem cell harvest by co-administration of recombinant human (rh) interleukin-6 (IL-6) and rh granulocyte colony-stimulating factor (G-CSF) in normal mice. In the present study, to evaluate further the utility of this observation for autologous peripheral blood stem cell transplantation, we examined the effects of rhIL-6 and rhG-CSF on peripheral blood granulocyte-macrophage colony-forming units (CFU-GM) in carboplatin (CBDCA)-induced and irradiation-induced myelosuppressive mouse models. After CBDCA administration, blood cell counts decreased to the nadir, and then recovered to a normal level. In this recovery phase, the peripheral CFU-GM level increased to 3.8-fold higher than the pretreatment level. Administration of rhIL-6 (10 microgram/day) alone induced a 40-fold increase in peripheral CFU-GM from the normal level at day 14. In combination with rhG-CSF (0.35 microgram/day), which alone induced a 74-fold increase, rhIL-6 synergistically increased the CFU-GM level by 1200-fold. In irradiated mice, similar results were observed. Administration of rhIL-6 at 3 and 10 microgram/day significantly increased CFU-GM. Interestingly, in combination with rhG-CSF, a lower dose of rhIL-6 (1 microg/day) could induce CFU-GM increase. We also examined CFU-GM distribution in bone marrow, spleen and peripheral blood. Cytokine administration induced not only a change of CFU-GM distribution, but also an increase in total CFU-GM counts per mouse. These results suggest that co-administration of rhIL-6 and rhG-CSF may be useful for autologous peripheral blood stem cell transplantation.

The outbreak of mumps in a small island in Japan

A major mumps outbreak occurred on a small island, Ikeshima. in Nagasaki Prefecture from August 1994 to February 1995. There were 236 patients with the mumps at Ikeshima Miners' Hospital during that period. The Measles-Mumps-Rubella (MMR, Toitsukabu) vaccination coverage in the 43 children at the nursery school was 65.1% and it was 61.9% in the 21 children aged 4-5 years not attending the nursery school. Coverage was 66.6% in the 63 kindergarten students and 53.7% in 56 first-graders. The overall MMR vaccination coverage among these children was 61.7% (113/183) from 1989 to 1992. Children from the second grade to junior high school received monovalent mumps vaccine, Torii strain. None received Zishakabu MMR. The age of the patients ranged from 1 to 43 years, with a mean of 9.1 years. The majority (77.5%) were primary school children. The attack rates for vaccinated and unvaccinated children in grades one to six were: 6.7% (2/30) and 88.5% (23/26), 25% (3/12) and 44.1% (30/68), 11.1% (1/9) and 64.4% (29/45), 25% (2/8) and 60% (45/79), 22.2% (2/9) and 35.9% (28/78). 0% (0/5) and 24.7% (18/73), respectively. The overall frequency in the primary school was 41.4% (183/442 children). The frequency in the nursery school for children aged 4-5 years was 14.0% (6/43). It was 17.5% (11/63) in children aged 5-6 years in the kindergarten, 5.2% (11/213) in children not attending school with an age range of 1-5 years, and 4.2% (10/237) in junior high school students. Although the frequencies of MMR coverage for the nursery school children and kindergarteners were not high enough to eradicate mumps outbreaks, the MMR vaccination program was thought to have influenced the low frequency of mumps among the children. Close physical interactions among the first-graders would have contributed to their high frequency of mumps. Some patients presented with suspected mumps parotitis several times, but no such serological confirmation of reinfection was obtained.

Establishment of high- and low-invasion clones derived for a human tongue squamous-cell carcinoma cell line SAS

Distant-organ metastasis and regional lymph node metastasis are still the major cause of mortality of oral-cavity squamous-cell cancer (SCC). However, only a few studies have been undertaken to elucidate the mechanism of invasion and metastasis of oral SCC. In this study, we attempted to establish human oral SCC clones with different invasiveness, defined by endothelial cell monolayer assay, which can be used for the study of invasion and metastasis of oral SCC. We established five clones from the human oral SCC cell line SAS by a limiting-dilution method. Two distinct clones, SAS-L1 with very low invasive potential and SAS-H1 with very high invasive potential, were picked out by rat lung endothelial cell monolayer assay. The number of SAS-H1 that penetrated the rat lung endothelial cell monolayer was six fold higher than the number of SAS-L1. There were no differences of metalloproteinase production and cell adhesiveness to Matrigel of SAS-L1 and SAS-H1. However, SAS-H1 exhibited a higher migration ability than SAS-L1. This pair of clones would be a useful experimental model to help in the study of the invasiveness of human oral SCC.

Hemodynamics and oxygen consumption during warm heart surgery

We compared the effects of normothermic cardiopulmonary bypass (CPB) with those of hypothermic CPB in patients who underwent coronary artery bypass grafting (CABG) with respect to hemodynamics and oxygen balance. The patients in our study were divided into two groups according to temperature during CPB: systemic normothermia combined with warm blood cardioplegia (group W,n=36) and systemic hypothermia combined with cold crystalloid cardioplegia (group C,n=26). In group W, the use of directcurrent (DC) defibrillators was less frequent after release of the cross clamp, and the duration of CPB and of reperfusion was shorter. After CPB, the cardiac index and arterial pressure were higher and the dosages of dopamine were lower in group W than in group C. The serum glucose level during and after CPB was lower and the base excess during CPB was higher in group W than in group C. Oxygen consumption ([Formula: see text]) was unchanged throughout the operation in group W, while it decreased during CPB and increased at the end of surgery in group C. The oxygen extraction ratio (ERo2) increased during CPB in group W, while it was unchanged throughout the operation in group C. Mixed venous oxygen saturation ([Formula: see text]) was maintained above 65% during and after CPB in group W and group C. Our results showed that normothermia may be superior to hypothermia during CPB with respect to recovery of cardiac function and avoidance of hyperglycemia. The whole-body oxygen demand-supply balance may be preserved during normothermic as well as hypothermic CPB.