Strain dependency of B and T lymphoma development in immunoglobulin heavy chain enhancer (E mu)-myc transgenic mice.

The transgenic mice were produced by injecting eggs of B6 and C3H/HeJ mice with the human E mu-myc gene. Preferential development of B lymphomas was observed in the B6 transgenic mice, whereas the C3H/HeJ transgenic mice developed mostly T lymphomas. The phenotypic activation of B lineage cells but not of T lineage cells was detected in the prelymphomatous transgenic mice of both strains. The transgene was similarly expressed in B and T cells of the transgenic mice of both strains. These results suggest that a high incidence of T lymphomas in the C3H/HeJ transgenic mice may not be due to the preferential activation of or the preferential E mu-myc expression in T lymphocytes. When the bone marrow or fetal liver cells from the prelymphomatous transgenic mice of both strains were transferred into irradiated normal C3H/HeJ mice, most of the recipients developed T lymphomas. Moreover, even when irradiated B6 mice received the hematopoietic stem cells from the prelymphomatous B6 transgenic mice, the incidence of T lymphoma increased up to 50%. These findings suggest that B6 and C3H/HeJ mice might provide the environment that supports the development or growth of B and T lymphomas, respectively, and that such an environment could be modified by irradiation of the mice.

A transgenic mouse model with cyclin D1 overexpression results in cell cycle, epidermal growth factor receptor, and p53 abnormalities.

The cyclin D1 oncogene is critical in the progression of the cell cycle through the G1 phase. It is frequently overexpressed in squamous cell carcinomas originating from the head/neck and esophagus. Yet, the functional consequences of aberrant cyclin D1 overexpression are not entirely understood apart from increased cell proliferation. To address this question, we have developed a transgenic mouse model in which the EBV ED-L2 promoter targets cyclin D1 to the stratified squamous epithelium in a tissue-specific fashion to the tongue and esophagus, thereby resulting in a dysplastic phenotype. We now demonstrate that the dysplastic phenotype is associated with increased cell proliferation based on proliferating cell nuclear antigen overexpression and abnormalities in cyclin-dependent kinase 4, epidermal growth factor receptor, and p53. In aggregate, these studies suggest that alterations in certain oncogenes and tumor suppressor genes occur early during head/neck and esophageal carcinogenesis.

Delayed oxidation of intramitochondrial pyridine nucleotide oxidoreduction state as compared with tissue oxygenation in human liver transplantation.

Intra- and post-operative oxygenation of graft liver and subsequent oxidation of the intramitochondrial oxido-reduction state of pyridine nucleotide were studied in partial liver transplantation from living related donors with the ratio of acetoacetate to beta-hydroxybutyrate in arterial blood (AKBR), the ratio of oxidized flavoprotein to reduced pyridine nucleotide (FP/PN ratio) and oxygen saturation of hemoglobin in liver tissue (hepatic SO2). Decreased hepatic SO2 and its heterogenous distribution after reflow of portal vein and hepatic artery were normalized by the end of operation, while the intramitochondrial oxido-reduction state was still reduced at the end of operation and was normalized only at 24 h after the operation. The observed delay in oxidation of the intramitochondrial oxido-reduction state as compared with tissue oxygenation indicates the transition of the intramitochondrial oxido-reduction state associated with the initiation of metabolic activity from the cold preserved state, and suggests an important role for microcirculation in the normalization of the oxido-reduction state.

Changes in the distribution of the control of the mitochondrial oxidative phosphorylation in regenerating rabbit liver.

Applying the metabolic control theory, inhibitor titration studies were carried out on Complex I, III, IV, ATP synthase, ATP/ADP carrier and P(i) carrier of mitochondrial oxidative phosphorylation in normal and regenerating rabbit liver in order to examine the acceleration mechanism of mitochondrial oxidative phosphorylation. In regenerating rabbit liver the rate of state 3 respiration, respiratory control ratio and phosphorylation rate in the presence of mM glutamate, 250 microM ADP and 3 mM inorganic phosphate increased significantly as compared with the control by 73%, 48% and 76%, respectively. The control of the rate of state 3 respiration in normal liver was exerted by Complexes I, IV and steps other than the aforementioned six steps, whose flux control coefficients were 0.317, 0.214 and 0.469, respectively. By contrast, in regenerating liver, the control was more evenly distributed among these steps in oxidative phosphorylation and the possibility is suggested that Complexes I, IV and steps other than the six steps are activated during regeneration. The activation of Complexes I and IV was attributed to their increased activity, since it was not accompanied by an increase in the amount of the enzymes.

Quantitative analysis of redox gradient within the rat liver acini by fluorescence images: effects of glucagon perfusion.

The redox gradient along the sinusoid in the rat liver was studied using a redox scanner, a device based on tissue fluorescence scanning spectroscopy measuring the fluorescence signals of oxidized flavoprotein (FP) and reduced pyridine nucleotide (PN). The FP/(FP+PN) ratio reflects the mitochondrial redox state in the liver tissue. The distribution of mitochondrial redox state on the scanned area is expressed as two-dimensional gray-scale images with a 20 micron resolution. Using this instrument, we have scanned a 2.5 x 2.5 mm area of the frozen rat liver sample to investigate the redox gradient within acini and the effects of glucagon on the changes in the redox distribution. The redox images obtained in the perfused livers showed mosaic patterns implicating a regular heterogeneity of redox state in an acinus. The analysis of gradient curve, furthermore, clarified that the redox level in an acinus decreased sigmoidally from the periportal to the pericentral region. Glucagon, which has been reported to reduce the intracellular redox state, decreased the redox potential in whole acini, especially, in the periportal region, when compared with the perfusion without glucagon. These results strongly indicate an intraacinus heterogeneity of glucagon function, with glucagon selectively operating in the upstream of the sinusoid.

Physical fitness. Its contribution to serum high density lipoprotein.

The effects of exercise conditioning on serum high density lipoprotein cholesterol (HDL-C) were studied using 20 members of a regular joggers club and other healthy non-member subjects of varying degrees of habitual physical activity (253 males and 391 females). Both the HDL-C and HDL-C/serum total cholesterol (TC) levels were significantly higher with the 20 regular joggers than with the sedentary controls matched for age, TC, serum triglycerides (TG) and weight index (WI). A significant correlation was found between HDL-C/TC and the exercise conditioning value obtained by using the results of the 12-min performance test as an index among the non-member subjects. In order to ascertain the relative significance of exercise conditioning in influencing HDL-C/TC, a multiple regression analysis was conducted using HDL-C/TC as the variable criterion. The results showed that TG affected HDL-C/TC the most among both males and females, while exercise conditioning affected it second among males and fourth among females.

Living related liver transplantation across ABO blood groups.

We performed 13 pediatric liver transplants from ABO-incompatible living related maternal or paternal donors using a combination of preoperative removal of isohemagglutinin and postoperative immunosuppressive therapy with FK506 and prophylactic OKT3. Tissue near-infrared spectroscopy was applied to evaluate hemodynamics using the hemoglobin of red cells in the sinusoids as an index. The data obtained indicated that the preoperative removal of isohemagglutinin prevented hyperacute humoral rejection with hemorrhagic infiltration in the sinusoids in 10 successful cases. The incidence of acute rejection was not significantly different among ABO-identical, -compatible, and -incompatible groups. The estimated 1-year survival rate of the ABO-incompatible group was 77%.

Changes in glucose transporter 2 and carbohydrate-metabolizing enzymes in the liver during cold preservation and warm ischemia.

In order to examine glucose metabolism in liver grafts during cold preservation (24 and 48 hr), warm ischemia (60 and 120 min), a combination of the two and reperfusion, the amount of protein and mRNA of glucose transporter 2 and the activities of enzymes in glycolysis (glucokinase, phosphofructokinase, pyruvatekinase), gluconeogenesis (glucose 6-phosphatase, fructose 1,6-bisphosphatase), and the pentose phosphate pathway (glucose 6-phosphate dehydrogenase) were measured. It appeared that glucose transport, the pentose phosphate pathway, and gluconeogenesis were maintained during cold preservation and warm ischemia. The activity of glucokinase significantly decreased from the control value of 1.33 +/- 0.23 IU/g protein to 0.70 +/- 0.17 (24 hr, P<0.05) and 0.57 +/- 0.12 (48 hr, P<0.01) only during cold preservation. However, the activity of phosphofructokinase significantly decreased from the control value of 4.37 +/- 0.06 IU/g protein to 2.67 +/- 0.15 (60 min, P<0.0001) and 1.53 +/- 0.06 (120 min, P<0.0001) only during warm ischemia. This indicates that glycolysis deteriorates during both cold preservation and warm ischemia and demonstrates further that the balance between glycolysis and gluconeogenesis shifts to gluconeogenesis. Even when cold preservation was combined with warm ischemia, the activity of glucokinase decreased only during cold preservation and the activity of phosphofructokinase decreased only during warm ischemia. Furthermore, these changes were time-dependent. It is suggested that they can be used as a clock to measure the durations of cold preservation and warm ischemia separately and that the magnitude of an ischemic injury to a liver and a liver graft's viability can be indirectly estimated before transplantation.

Experiences of 120 microsurgical reconstructions of hepatic artery in living related liver transplantation.

BACKGROUND: We reviewed 120 microsurgical reconstructions of a hepatic artery in living related liver transplantation and discussed the problems encountered. METHODS: From January 1991 to July 1994 we performed a series of 105 living related liver transplantations on children with end-stage liver disease. Arterial reconstruction was performed under the optical field of a continuous zoom magnification of approximately 10 times with an operating microscope. RESULTS: Twenty-six percent of the graft arteries were less than 2 mm in diameter. The time required for an arterial reconstruction was 49.5 +/- 1.8 minutes. In 15 of the 31 cases in which there were two graft arteries, two arterial reconstructions were required. The caliber differences between the graft artery and the recipient artery in 30 instances was dealt with by cutting an undersized artery obliquely (17 instances), by fish-mouth method (10 instances), by end-to-side anastomosis (1 instance), or by funnelization method (2 instances). In one case we performed an intimal dissection of a recipient hepatic artery and substituted a splenic artery. Consequently, hepatic arterial thrombosis occurred in only two cases (1.7%). CONCLUSIONS: Microsurgical technique has overcome the high risk of hepatic arterial thrombosis in cases of fine graft arteries, enabled the reconstruction of arteries with caliber difference, and decreased arterial complications with its delicate manipulation.

Upper gastrointestinal bleeding arising from metastatic testicular tumor.

We report a young man with a testicular tumor in whom the first symptom was upper gastrointestinal bleeding. This was caused by invasion of the duodenum by a metastatic lesion in a retroperitoneal lymph node. Metastatic testicular tumor is a rare cause of upper gastrointestinal bleeding. Diagnosis was difficult because the primary lesion could not be found initially. In young men with upper gastrointestinal bleeding, the possibility of metastatic testicular tumor should be investigated.

Analysis of factors affecting the graft oxygenation state in living related liver transplantation.

BACKGROUND/AIMS: In liver transplantation, graft dysoxia after reperfusion may lead to graft failure. The aim of this study is to investigate the relationship between the factors, which were supposed to affect the oxygen supply to the graft, and the oxygenation state of the graft in order to determine which factor is important to prevent the graft from dysoxia. MATERIALS AND METHODS: The relationship between oxygen supply and oxygenation state of the graft was investigated in 56 successful cases of living related liver transplantation. Factors affecting the oxygen supply to the graft were considered as follows; portal venous flow (PVF), mean velocity of the hepatic artery (HA-Vm), hemoglobin concentration in the peripheral blood (Hb), size of the graft liver relative to the recipient body weight (G/R ratio), partial oxygen pressure in the arterial blood (PaO2), and rate-pressure product (BP*PR). Oxygenation state of the graft was estimated by oxygen saturation of hemoglobin in the graft tissue (graft SO2) as measured by tissue near infrared spectroscopy. RESULTS: 1) Graft SO2 was rather independent of PVF and HA-Vm probably due to compensatory interrelation between the portal venous flow and hepatic arterial flow. 2) Significant correlation between G/R ratio and graft SO2 was observed after portal reflow (p < 0.01), but the correlation diminished after hepatic arterial reflow. Positive correlation between G/R ratio and AKBR after portal reflow suggested that the graft with large G/R ratio is likely to suffer dysoxia early after reperfusion. 3) Graft SO2 was positively correlated with Hb (p < 0.05), while there was no significant correlation between graft SO2 and PaO2 or BP*PR. CONCLUSION: This study clarified the contribution of the factors which were supposed to affect the oxygen supply to the graft and the oxygenation state of the graft, and which factor is important to prevent the graft from dysoxia.

Evaluation of body composition using dual-energy X-ray absorptiometry, skinfold thickness and bioelectrical impedance analysis in Japanese female college students.

We compared three methods for evaluating body composition: dual-energy X-ray absorptiometry (DXA), skinfold thickness (Skinfolds), and bioelectrical impedance analysis (BIA). Subjects were 155 healthy young college-aged Japanese females whose mean+/-SD (range) age, body height, body weight and body mass index (BMI) were 20.1+/-0.3 (19.6-21.1) y, 158.9+/-4.7 (145.4-172.6) cm, 52.0+/-6.8 (39.4-84.6) kg and 20.6+/-2.3 (16.5-32.5), respectively. Their mean skinfold thickness at the triceps and subscapular were 16.9+/-4.7 (8.0-31.0) and 16.0+/-5.7 (7.0-40.0) mm, respectively. Mean body fat mass percentages evaluated by DXA, Skinfolds and BIA were 29.6+/-5.1, 22.8+/- 5.3 and 25.8+/-4.7%, respectively. Body fat mass was 15.4+/-4.4, 12.1+/-4.5 and 13.6+/-4.5 kg, respectively. Simple correlation coefficients between the three methods for body fat mass percentages provided the following coefficients: r=0.741 for DXA vs. Skinfolds, r=0.792 for DXA vs. BIA and r=0.781 for Skinfolds vs. BIA. Simple correlation coefficients for body fat mass were as follows: r=0.898 for DXA vs. Skinfolds, r=0.927 for DXA vs. BIA and r=0.910 for Skinfolds vs. BIA (all p<0.001). There were significant differences in the values among the three methods with the Skinfolds providing the lowest body fat mass and percentage, and DXA the highest (p<0.001). They all appear to be strongly correlated for evaluating body composition: however, different cut-off values for defining obese and lean need to be defined for each method.

[Prophylaxis of thrombosis in a pregnant woman with congenital antithrombin III deficiency: changes in hemostatic molecular markers before the onset of thrombosis].

A pregnant woman with congenital antithrombin III (AT III) deficiency was given AT III concentrate and warfarin at the first and after 36th week of gestation periods and at the other gestation period, respectively. The patient developed thrombosis in the left leg, but fibrinopeptide A (FPA) and thrombin-AT III complex (TAT) had already shown high values one week before, suggesting the possibility of their being forecast markers of thrombosis. The administration of AT III concentrate caused an improvement in thrombosis. Therefore, in case of high FPA and TAT values as determined one or two times a week, the administration of AT III concentrate was thought necessary. In case of warfarin, however, non-administration during the 6th-9th weeks of gestation for the purpose of avoiding teratogenicity and frequent blood coagulation tests taking heed of overdosage for the purpose of avoiding fetal central nervous system abnormalities were suggested necessary. Delivery was uneventful, both mother and child being doing very well; umbilical blood AT III activity was 18%. It is generally difficult for us to form the diagnosis as AT III deficiency only from AT III activity at neonatal stage, but in the present study, we analyzed the restriction fragment length polymorphism of the AT III gene using umbilical blood, and succeeded in diagnosing the neonatal child as AT III deficiency.