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In the fields of psychiatry and neurology, the dopaminergic system is one of the most important neurotransmitter systems in the brain. Whereas pharmacological and biochemical studies had initially indicated two subclasses of dopamine receptors (DA-R), recent progress in molecular biology techniques has led to the identification of five distinct genes of DA-Rs (D1-R-D5-R) and splice variants. The gene products are classified into the D1-R family (D1-R and D5-R) and D2-R family (D2-R, D3-R and D4-R) based on their structure and pharmacological features. This review summarizes the structure, localization, function and pharmacology of DA-R subtypes on the basis of knowledge obtained during the past few years. The genes encoding the D1-R family have no intron and the D2-R family genes have introns. The distributions of mRNAs encoding these five DA-R subtypes in the brain were different from their respective receptors. The localization of DA-R subtypes to particular brain regions and specific pharmacological profiles of DA-R subtypes allow new insights to be made into the mechanism of action of DA in the control of psychiatric and motor functions. The availability of detailed information about DA-R subtypes will not only clarify their roles in the brain, but will probably also lead to the development of new therapeutic drugs with more specific actions.

The establishment of a model system of neoplastic transformation of normal human cells has been attempted with a chemical carcinogen, 4-nitroquinoline 1-oxide (4NQO). In the course of these experiments, it was noticed that immortalization of human cells is a multi-step process involving several mutational genetic events. Thus, chromosomal changes which occurred during the process of immortalization of human fibroblasts were examined. To accomplish immortalization, fibroblasts obtained from an embryo were repeatedly treated with 10_-6M4NQO from primary culture to passage 51 (59 treatments in total). Before immortalization, some chromosomes (especially, chromosomes 2, 6, 8, 10, 11, 12, 15, 19, and 20), were lost at a relatively high frequency. After immortalization, the chromosomes distributed so broadly in the triploid to hypotetraploid region without a distinct modal number or without marker chromosomes that it was difficult to identify the specific chromosomes related to the immortalization of human cells. No specific structural chromosomal changes were detected. Although the significance of such chromosome changes in relation to immortalization is not clear, the loss of some specific chromosomes suggests that genes which are involved in cellular aging and which suppress immortalization may have been lost in the immortalization process.

Tissue PIVKA-II was examined in 32 hepatocellular carcinomas and 2 metastatic liver tumors using indirect immunofluorescence, and the results were compared with the size, histological grading and serum PIVKA-II level. The specificity of this method was confirmed by the disappearance of reactivity in PLC/PRF/5 cells after the addition of vitamin K to the culture medium. Positive PIVKA-II staining was observed as a clustered or a single cell pattern only in the HCC nodules, but not in the surrounding cirrhotic tissue. PIVKA-II staining was observed in all HCC groups regardless of histological grade. There was no relationship between PIVKA-II staining and the size of HCC. PIVKA-II was detected immunohistochemically even in small HCC of patients whose plasma PIVKA-II levels were below the detection limit. These results suggest that PIVKA-II production is a specific phenotype of HCC regardless of its histological grading and demonstrate that this immunofluorescent PIVKA-II staining is more sensitive and useful than plasma PIVKA-II assay for the diagnosis of HCC.

In single treatment study, ethanol was administered intraperitoneally to ICR mice (about 34 g) in the amounts of 1.0, 2.0, 3.0 or 4.0 g/kg body weight. The 3,4-dihydroxyphenylacetic acid (DOPAC) + homovanillic acid (HVA) concentration in the striatum was elevated with 3.0 and 4.0 g/kg of ethanol. In the hypothalamus, the DOPAC, HVA and 5-hydroxyindoleacetic acid concentrations were increased after injection of 3.0 and 4.0 g/kg of ethanol. Furthermore, the acetylcholine (ACh) and gamma-aminobutyric acid (GABA) concentrations were also increased following the injection of 1.0, 2.0, 3.0 and 4.0 g/kg. To study the effects of repeated administration, mice were injected intraperitoneally with 1.0 or 2.0 g/kg of ethanol once daily for 7 days. The DOPAC + HVA level in the striatum was elevated after injection of 1.0 and 2.0 g/kg of ethanol. The GABA and ACh concentrations in the hypothalamus were decreased after repeated injections of ethanol. These results suggest that ethanol significantly alters the utilization of dopamine, ACh and GABA in the hypothalamus. This may partially explain why ethanol has such profound effects on emotional behavior and mood.

Stress distribution in the first carpometacarpal joint was analyzed in 49 cadaveric hands using the finite element method to clarify the pathogenesis of osteoarthritis in the joint. The results of the finite element method analysis were compared with those of the contact pressure distribution in the first carpometacarpal joint of cadaveric specimens using pressure-sensitive film, and with the simple roentgenographical and microradiographical manifestations of spur formation, and with histological findings of osteoarthritis to verify the accuracy of the models of computer simulation models. The comparison of these results showed that osteoarthritic changes of the first carpometacarpal joint were found in areas where stress was concentrated during movement of the joint. The saddle shape of this joint is essentially well-designed for the dispersion of normal stress, however minimal displacement due to instability could easily induce osteoarthritis. Furthermore the shallow trapezial configuration may contribute to the high incidence of osteoarthritis changes. The finite element method helped clarify the relationship between stress patterns and osteoarthritis response.

The effects of intraperitoneal administration of 2-(4-carboxy-D-gluco-tetrahydroxybutyl)thiazolidine-4-carboxylic acid (CGUA), a cysteine derivative conjugated with glucuronic acid, on total glutathione and total cysteine contents in rat tissues were investigated. Total glutathione (GSH and GSSG) and total cysteine (cysteine and cystine) were determined by a new method consisting of preparation of S-carboxymethylglutathione (CMSG) and S-carboxymethylcysteine (CMC), respectively, and subsequent analyses with an amino acid analyzer. CGUA was determined by a coloration method employing an acidic ninhydrin reagent. Total cysteine contents in liver, kidney and plasma rapidly increased to 2.3, 2.7 and 6.5 times the levels of the controls, respectively, after CGUA administration at a dose of 5 mmol/kg of body weight. Total glutathione content did not change significantly in the liver or blood except for the kidney with a significant increase during the first 1-h period after administration. CGUA content increased markedly in these tissues, especially in the kidney, and 30% of administered CGUA was excreted in urine within 2h. These results indicate that CGUA is converted into cysteine in vivo, suggesting the usefulness of this compound for protection of the kidney and the liver.

To clarify the immunological function of 'M' (microfold or membranous) cells in the large intestine, we examined the expression of intercellular adhesion molecule-1 (ICAM-1) and HLA-class II antigens immunohistochemically in M cells and follicle-associated epithelia (FAE) covering isolated lymphoid follicles of the human colon in comparison with their expression in Peyer's patches of the small intestine. In Peyer's patches of the small intestine, ICAM-1 was not expressed on the epithelial cells covering the lymphoid follicles, but their cell surfaces were stained positively for HLA-DR. In contrast, colonic M cells expressed ICAM-1 on their cell surfaces but were negative for HLA class II antigens. By immunoelectron microscopy, ICAM-1 was seen to be distributed on the surface of microfolds, on the membranes of apical vesicles and on part of the basolateral plasma membranes of M cells, but was not expressed on adjacent FAE. These findings imply that the M cells in the colon and in Peyer's patches have different immunological roles. In addition, identification of ICAM-1 expression on the colonic M cells should help elucidate the pathogenesis of some inflammatory colonic diseases which appear to start in the lymphoid follicles of the colonic mucosa.

Left ventricular assist device (LVAD) was utilized for the treatment of postcardiotomy heart failure in two patients with Marfan's syndrome. Patient 1 (a 22-year-old) with annuloaortic ectasia (AAE) and DeBakey type II dissection had been supported by LVAD for 87h after composite graft replacement of the ascending aorta and aortic valve. Patient 2 (a 52-year-old) with AAE and DeBakey type I dissection had been supported by LVAD for 91 h after aortic valve replacement. During the assist, both patients complicated bleeding from the fragile left atria near the sites of cannulation. Patient 1 died of multiple organ failure on the 62nd postoperative day, but patient 2 returned to work after surgery.

"Free" iron, a potentially radical-generating low mass iron, and not found in normal human blood, was increased in the serum of blood-transfused thalassemia major patients seen in the Yangon General Hospital, Yangon, Myanmar (Burma). The low mass iron was detected by the bleomycin assay. Fifty-one blood samples were analyzed (from 28 males and 23 females). High "free" iron was detected in 47 sera samples from thalassemia patients. Serum ferritin, which reflects the body store iron, was higher than the normal range (10-200 ng/ml) in 49 patients. On the other hand, serum iron of 39 sera samples fell within the normal range (50-150 micrograms/dl). Four were less than 50 micrograms/dl and eight were more than 150 micrograms/dl. Almost all the patients' sera of normal or higher serum iron level contained "free" iron. Thus, almost all the sera from thalassemic patients from Myanmar contain bleomycin-detectable iron, even when serum iron is within the normal range. In developing countries where undernutrition is prevalent (serum albumin in these patients was 3.6 +/- 0.4 g/dl, P < 0.0001 vs. control value of 4.0 - 4.8 g/dl), normal serum iron does not preclude the presence of free iron in the serum.

To study the virological and serological characteristics of asymptomatic hepatitis C virus (HCV) carriers, 165 blood donors positive for antibody against HCV proteins by the second generation assay, were analyzed for their clinical backgrounds, serological reactivity against antigens derived from HCV by recombinant immunoblot assay, and the amount and genotype of HCV by the polymerase chain reaction. Compared with blood donors having abnormal levels of alanine aminotransferase (ALT), sera from the donors with normal levels of ALT reacted less frequently against NS4 antigens (anti-5-1-1: 34.4% vs. 54.5%, P = 0.0609; anti-c100-3: 34.4% vs. 56.1%, P < 0.05). Also the positivity for antibodies against these antigens were more frequent in sera from donors with genotype 1b HCV-RNA than other genotypes (anti-5-1-1: 61.0% vs. 23.5%, P < 0.01; anti-c 100-3: 61.0% vs. 26.5%, P < 0.01). The prevalence of each genotype in blood donors with normal ALT levels was different from that in patients with advanced liver disease (P < 0.05), genotype 1b being less and genotype 2a being more frequent. The number of HCV-RNA copies/0.5 ml in donors with normal ALT was 10(7.9 +/- 1.0) (n = 27) and that in patients with chronic liver disease was 10(7.4 +/- 0.8) (n = 116), the difference being statistically significant (P < 0.05). In conclusion, the results of this study suggest that asymptomatic blood donors carrying HCV have the serological and virological characteristics different from the patients with advanced liver disease.

To find an effective way to handle wheelchairs, 3-dimensional floor reactions of the hand and angular deviation of the elbow and wrist joints during push-up motion were studied in 10 healthy men. The push-up was carried out using 3 hand positions (fist, finger and palm) and a push-up device. In all hand positions, anteroposterior force (Fx) and the mediolateral force (Fy) appeared after the vertical force (Fz). The end point of Fx and Fy was observed before that of Fz. Among the 4 different hand positions, Fx and Fy appeared first in the palm, followed by the finger and fist positions, and lastly in the push-up devices. The results indicate that the more unstable pushing-up the body is, the earlier and longer Fx and Fy are. Thus, Fx and Fy are considered to be good indicators of body balance during the push-up motion. The elbow joint showed a hyperextended position only when using the palm position in the maintenance phase. The wrist joint showed palmar flexion only when using the fist position.

A persistent problem in orthotopic liver transplantation is primary nonfunction (PNF) of the hepatic allograft. In an attempt to reduce the incidence of graft failure, the feasibility of pretransplant assessment of graft viability was investigated by 31P nuclear magnetic resonance (NMR) spectroscopy. The level of adenosine triphosphate (ATP) was measured as an indicator of liver function by 31P NMR spectroscopy after a 30 min normothermic reperfusion following cold-storage in University of Wisconsin (UW) solution. The mean +/- SD beta-ATP/Pi ratio after preservation for 0, 12, 24 or 48 h was 1.40 +/- 0.34, 0.85 +/- 0.27, 0.64 +/- 0.14 and 0.38 +/- 0.09, respectively. Significance was observed between 12h and 24h and between 12h and 48h of preservation. These results correlated well with the morphological changes in endothelial cells and sinusoidal lining cells examined by transmission electron microscopy. It is suggested strongly that microcirculatory disturbances due to endothelial cell injury impairs the recovery of ATP levels after reperfusion, and that ATP determination by 31P NMR spectroscopy, as a non-invasive modality, may help in the prediction of PNF after liver transplantation.

The presence of high-risk types of human papillomavirus (HPV) 16, 18 and 33 in cell lines established from several malignancies including 5 of cervical cancer and 6 of head and neck cancer was studied. HPV DNA, either type 16 or 18, was detected by polymerase chain reaction, and by Southern blot hybridization in all of the cell lines derived from cervical cancers. The hybridization patterns of HPV DNA after endonuclease digestion differed among cell lines, suggesting that all of these cell lines were independent isolates. Accordingly, high-risk types of HPV DNA seem to be ubiquitous in cervical cancer. HPV DNA was not detected in the cell lines derived from head and neck cancers or from any other malignancies besides cervical cancer in this study.

Monoclonal antibodies were raised against urine proteins from diabetic patients. An antibody, YO-2, stained three protein bands with apparent molecular weights of 66, 49, and 36 kDa. These bands were not reactive with an anti-human albumin antibody. The urine levels of YO-2-reactive antigen in the normal control were 0.97 +/- 0.37 U/g-Cr (units per gram of urine creatinine) (mean +/- SD). Those of the normo-, micro-, and macroalbuminuric diabetic patients, respectively, were 1.38 +/- 1.36, 2.87 +/- 2.07, and 3.92 +/- 3.33 U/g-Cr. They were significantly higher in the micro- and macroalbuminuric patients. The urine levels of YO-2-reactive antigen had no significant correlation with the urine albumin levels and hemoglobin A1c. We concluded that; a) monoclonal antibody YO-2 recognized a non-albumin urine antigen increasingly excreted in diabetic patients with nephropathy, b) recent glycemic control of diabetes would not significantly affect the urinary excretion rate of YO-2-reactive antigen, and c) the excretion rate and probably the mechanism of YO-2-reactive protein differed from those of albumin. The urine levels of YO-2-reactive antigen could be a clinical marker of diabetic nephropathy.

In this study, we established the surgical procedure and postoperative care of multivisceral transplantation (MVTX) in pigs, and examined the functional changes and rejection pattern of transplanted organs in MVTX. Twenty-two MVTXs were performed without immunosuppression, and nine cases (41%) that survived for 5 days or more after MVTX were used for evaluation. Rejection in grafts including the liver, pancreas, and gastrointestinal tract were assessed histopathologically. On day 5 after transplantation, the duodenum and small bowel already showed signs of mild rejection. On the other hand, in the liver, pancreas and stomach, rejection occurred later and was still mild on day 16. Hepatic rejection in MVTX appeared to occur later than in simple liver transplantation (LTX). These results showed that the susceptibility to rejection of individual visceral organs varies.

The effect of cigarette smoke on organ weights, lipid peroxidation and plasma biochemical parameters was investigated in male Wistar rats. Daily exposure (for 20 min twice a day) to cigarette smoke for 27 days caused a significant decrease in liver weight and a significant increase in lung weight. The smoke-exposure group showed increased lipid peroxidation in the liver, but not in the lung. In the smoke-exposure group, the GOT, gamma-GTP, total bilirubin and LDH values were significantly higher than those in the control group, while the plasma glucose value was significantly lower. These results suggest that cigarette smoking might induce liver injury by enhancing lipid peroxidation.

The possible role of nitric oxide (NO) and vasoactive intestinal polypeptide on isoprenaline-induced relaxation of the mouse longitudinal gastric fundal strips precontracted with 5.4 x 10(-7) M carbachol was investigated. Isoprenaline (5 x 10(-7) M, 10(-6) M and 5 x 10(-6) M) produced a concentration-dependent relaxations. NG-nitro L-arginine (10(-4) M) partly inhibited isoprenaline-induced relaxation. The inhibitory action of NG-nitro L-arginine was reversed by 4 x 10(-4) M L-arginine but not by 4 x 10(-4) M D-arginine. NG-nitro L-arginine (10(-4) M) did not affect the relaxation caused by sodium nitroprusside (10(-6) M). Vasoactive intestinal polypeptide antibody 7913 (1:160 dilution) partly inhibited isoprenaline-induced relaxation. This inhibition was greater on the response to the higher isoprenaline concentration (5 x 10(-6) M) than to the lower concentration (10(-6) M). The combination of vasoactive intestinal polypeptide antibody and NG-nitro L-arginine significantly enhanced the inhibition on 10(-6) M isoprenaline action. These results suggest that nitric oxide and vasoactive intestinal polypeptide may partly contribute to the relaxation induced by isoprenaline in the mouse gastric fundus precontracted with carbachol.

<p>To assess the role of the kidney dopamine system on the diuretic state induced by angiotensin-converting enzyme (ACE) inhibitors, we examined the changes in urinary excretion and plasma level of dopamine, and kidney dopamine receptors in spontaneously hypertensive rats (SHR) treated with cilazapril, an ACE inhibitor. We administered cilazapril 10 mg/kg orally to 13-week-old SHR daily for 21 days (CILAZA group). Systolic blood pressure was significantly decreased in the CILAZA group on Day 6 compared with that in vehicle-treated SHR (control group). The urine volume was three- to fivefold higher in the CILAZA group, and total urinary dopamine secretion was also increased compared with the control group. There was no significant difference in affinity and number of kidney dopamine receptors between the CILAZA and the control groups. In conclusion, the diuretic effect caused by cilazapril is partly mediated by inhibition of the water reabsorption via the increase of dopamine production in the kidney.</p>

The antitumor effects of indomethacin and interleukin 2 (IL-2) were studied in C3H/HeJ mice inoculated with MH134 hepatoma cells. Combined treatment with indomethacin and IL-2 augmented natural killer (NK) cells in mice with MH134-induced peritoneal carcinomatosis, and the survival of the treated mice was significantly longer than the non-treated mice. In animals with subcutaneous MH134 tumors, the combined therapy with indomethacin and IL-2 significantly suppressed tumor growth and induced complete regression of the tumor in three out of five mice. These results suggest that indomethacin and IL-2 therapy could be effective on human gastrointestinal cancer cells as well.