Acta Medica Okayama volume52 issue3

With advances in lectin affinity electrophoresis of alpha-fetoprotein (AFP), the detection of significant changes in serum AFP at low levels in cirrhotics has become important for early detection of hepatocellular carcinoma. Serum AFP levels of 616 healthy individuals without abnormal liver function tests or virus markers of hepatitis B and C were determined by enzyme immunoassay with IMx-AFP Dainapack using automated IMx apparatus set at twice the ordinary sensitivity and compared with those of 241 individuals with abnormal liver function tests and/or positive hepatitis virus markers. The coefficient of variation in this assay was less than 10% at AFP levels as low as 0.2 ng/ml with a lower detection limit of 0.1 ng/ml. The AFP level of healthy population showed a Gaussian distribution curve after logarithmic transformation with a median and 2.5-97.5 percentile reference range of 2.2 (0.6-5.6) ng/ml. There was no significant difference in the AFP level between males and females. Individuals with abnormal liver function tests alone showed no significant increase in serum AFP unless they were associated with positive hepatitis virus markers.

The cross-sensitization to stereotyped behavior between mazindol (MZD) and methamphetamine (MAP) was investigated in rats. MZD (5 and 10 mg/kg/day, p.o.), MAP (5 and 10 mg/kg/day, p.o.) and saline (1 ml/kg, p.o.) were administered once daily for a week. Challenge with MZD (10 mg/kg, p.o.) on the 8th day caused markedly stereotyped behavior in MAP-pretreated group compared with the saline-pretreated control group. MAP (10 mg/kg, p.o.)-induced stereotyped behavior on the 8th day was also greater in MZD-pretreated group rather than the saline-pretreated control group. These results suggest that repeated MZD and MAP administration cross-sensitizes to their stereotype-producing effects.

To test transdifferentiation of retinal pigment epithelial (RPE) cells in suspension culture, chick embryonic RPE sheets and dissociated RPE cells were cultured for two months in a non-adherent dish for suspension culture. RPE cells, isolated as a sheet, aggregated immediately and remained the same size with their differentiated characteristics for two months. The presence of basic fibroblast growth factor (bFGF) at concentrations of 10 ng/ml or higher induced the formation of a spherical lentoid structure which was positive for crystallin and bFGF receptor. In contrast, dissociated RPE cells did reaggregate but did not develop the lentoid structure even in the presence of bFGF. The transdifferentiation of RPE cells to the lentoid structure in this study was in contrast to their transdifferentiation to the retina, as reported in a previous study.

Steady-state serum concentrations of carbamazepine (CBZ) and valproic acid (VPA) were investigated in normal weight (body mass index; BMI 20 to 25), lean (smaller than 20 BMI) and moderately obese subjects (greater than 25 BMI) who received either 400 mg/day of CBZ or 800 mg/day of VPA. The CBZ serum concentration in lean subjects was significantly higher than that in normal weight subjects. However, no significant differences in VPA serum concentration were found between the three groups. The CBZ serum concentration decreased with increases in total body weight, and the VPA serum concentration decreased with increases in ideal body weight. However, both serum concentrations were not correlated with BMI. These results suggest that VPA doses should be calculated using ideal body weight and that degree of obesity may affect CBZ serum concentration rather than VPA serum concentration.

To study the effect of partial liquid ventilation (PLV) with perfluorocarbon on acute respiratory failure, 3 groups of 17 rabbits were examined to compare. After acute respiratory failure was induced by lung lavage with sea water in 12 of the 17 rabbits, 7 of the 12 rabbits were treated with conventional mechanical ventilation (AC group) and 5 of the 12 rabbits were treated with PLV using perfluorocarbon (AP group). The remaining 5 normal rabbits without acute respiratory failure were treated with PLV with perfluorocarbon as a control group (PL group). In the PL group, PaO2, PaCO2, blood pH, pulmonary compliance or pathological findings were not so changed after PLV. In the AC and AP groups, PaCO2 significantly increased, and in contrast, PaO2 and pulmonary compliance significantly decreased after lung lavage. However, these findings improved to almost the same levels as those of a control group within 2 h after the PLV treatment in the AP group, but in the AC group, these gradually deteriorated over time. As for the pathological findings, pulmonary vascular congestion, alveolar hemorrhage and inflammatory infiltration were observed in the AC group. However, these findings were not observed in the specimens of the AP group. From these results, PLV with perfluorocarbon was shown to be useful to improve gas exchange and pulmonary functions without major side effects.

An exposure to GB virus C/hepatitis G virus (GBV-C/HGV) was studied among populations at risk for blood and sexual exposure to analyze risk factor of the transmission of the virus. Blood samples were drawn from 98 intravenous drug users (IVDU), 100 female high-class commercial sex workers (CSW) and 50 male outpatients (MOP) at a sexually transmitted diseases (STD) clinic in Chiang Mai, Thailand. These blood samples were analyzed for GBV-C/HGV RNA; antibodies against second envelope protein of GBV-C/HGV (anti-E2); anti-hepatitis C virus antibody (HCV-Ab); hepatitis B core antibody (HBcAb); and antibodies against human immunodeficiency virus (HIV-Ab). Prevalences of GBV-C/HGV RNA, anti-E2, HCV-Ab, HBcAb and HIV-Ab were 27.6%, 16.3%, 84.7%, 76.5% and 45.0% in IVDU; 0%, 21.5%, 2.0%, 72.0% and 11.0% in CSW; 6.0%, 13.6%, 0%, 64.0% and 14.0% in MOP. While the prevalence of GBV-C/HGV RNA was higher in IVDU than in CSW and MOP, comparable prevalences of anti-E2 among the three populations were found. Intravenous drug injection showed association with GBV-C/HGV RNA, while history of STD associated with anti-E2. In conclusion, intravenous drug injection and STD were found to be risk factors for the previous exposure to GBV-C/HGV, but STD did not increase the risk of the GBV-C/HGV viraemia.

We investigated the degree of local heat and swelling of the thigh muscles produced by exercise. Eleven university athletes aged from 19 to 23 years old performed isokinetic exercise of the right knee on a Cybex II. Then serial determination of thigh circumference and thigh temperature (up to 120 min after exercise) as well as serial magnetic resonance (MR) imaging (up to 60 min after exercise) was performed on both thighs. The circumference of the right thigh peaked at 5.6 +/- 2.1 min after exercise and returned to normal at 38.6 +/- 9.2 min. The temperature of the right thigh peaked at 14.2 +/- 5.7 min after exercise and was not normalized after 120 min except in two subjects. T2-weighted MR images showed a marked increase in the signal intensity of the right knee flexor and extensor muscles. The signal intensity peaked immediately after exercise and subsequently decreased gradually but did not return to normal after 60 min in some muscles. Changes in the thigh circumference were closely correlated with changes in the MR findings. The changes in the thigh muscles after knee exercise could be demonstrated using MR imaging, thigh circumference, and thigh temperature data. These parameters may provide indicators for managing muscle fatigue and recovery.