Immobilization of sika deer with medetomidine and ketamine, and antagonism by atipamezole

Forty wild sika deer (Cervus nippon) were immobilized with medetomidine and ketamine and reversed by atipamezole in summer and fall captures from September 1994 to October 1995. For large yearling and older deer, mean +/- SD doses of 57.0+/-15.6 microg/kg medetomidine and 1.64+/-0.49 mg/kg (male) or 4.02+/-1.16 mg/kg (female) of ketamine were administered by intramuscular injection. For calves and small yearlings, 69.3+/-7.0 microg/kg medetomidine and 2.69+/-0.44 mg/kg ketamine were administered. While immobilized, deer were easy to handle, and muscles were well relaxed. After intramuscular administration of atipamezole (about 5 times the dose of medetomidine), deer recovered rapidly and smoothly.

Microscopic basis of free-volume concept as studied by quasielastic neutron scattering and positron annihilation lifetime spectroscopy

We have reexamined the free-volume concept presented by Cohen and Turnbull on the basis of two microscopic quantities: the excess mean-square displacement <u(2)>(f) and the total free volume V(PA,t), of poly- butadiene evaluated from the quasielastic neutron scattering and the positron annihilation lifetime spectroscopy (PALS) data, respectively. Comparing with the viscosity eta we found two relations, eta=eta(0) exp u( 2)(0)/<u(2)>(f) and eta=eta(0) exp V(*)(PA,0)/V(PA,t)=eta(0) exp V(*)(PA,0)/v(PA,f), where u(2)(0), V(*)(PA,0) and v(*)(PA,0) are the critical values for the mean-square displacement, the total PALS free volume, and the PALS free volume per molecule, respectively, and further v(*)(PA,0)=V(*)(PA,0)/N, N being the total number of molecules or segments. On the basis of these relations, we discuss the microscopic basis of the free-volume theory. The experimentally evaluated critical values u(2)(0) and v(*)(PA,0) are much larger than the average values of <u(2)>(f) and v(PA,f) calculated from the distributions. This has been explained from the low probability of escaping motions from a molecular cage. The free volume per monomer and the free-volume fraction were calculated from the excess mean-square displacement <u(2)>(f). The former was compared with the free-volume hole obtained by PALS, suggesting that 22 monomers are required for one PALS free-volume hole. The free-volume fraction obtained from the excess mean-square displacement was found to be 6.4% at 250 K, which is in reasonable agreement with that evaluated from the rheological data (9.0%).

Investigation of albumin-synthesizing ability in rat cirrhotic liver-derived hepatocytes using primary hepatocyte culture

BACKGROUND/AIMS

In cirrhosis, despite a decrease in the total number of hepatocytes, a normal serum albumin level is maintained during the compensatory stage of the disease in many cases. Therefore, to elucidate the mechanism in hepatocytes related to the regulation of the serum albumin level, the albumin-synthesizing ability of individual hepatocytes was investigated in cirrhotic rats.

METHODS

Cirrhotic rats were prepared by oral administration of furfural to male Wistar rats for 20 weeks. Albumin-synthesizing abilities of liver and of isolated hepatocyte culture were evaluated by measuring the albumin concentration in blood and culture supernatant. Expressions of albumin mRNA were compared using Northern blotting. Furthermore, transcriptional activity of the albumin gene was measured using the promoter domain of the gene.

RESULTS

The total number of hepatocytes in rat cirrhotic liver was significantly decreased compared to that in normal rat liver. However, there were no significant differences in levels of serum albumin or albumin mRNA expression between cirrhotic and normal liver. In primary hepatocyte culture, albumin mRNA expression, the amount of albumin secretion and the albumin promoter activity were clearly enhanced in cirrhotic hepatocytes compared to normal hepatocytes.

CONCLUSION

Although the total number of hepatocytes was decreased in the rat cirrhosis models used in this study, the serum albumin level was maintained and albumin-synthesizing ability was enhanced at the transcriptional level in the individual hepatocytes. These results suggest that the maintenance of serum albumin levels in compensated cirrhosis may be due to enhanced albumin synthesis by the hepatocytes.

Sarcomatoid hepatocellular-carcinoma showing rhabdomyoblastic differentiation in the adult cirrhotic liver

An unusual case of a massive liver tumour composed of rhabdomyosarcoma with a small focus of hepatocellular carcinoma in a 52-year-old man is presented. He had hepatitis B virus (HBV) surface antigen in his serum. Macroscopically, a large tumour with satellite nodules occupied the right lobe of the cirrhotic liver. Microscopically, the tumours were composed of small and short spindle-shaped undifferentiated cells, mixed with desmin-positive round rhabdomyoblasts and elongated striated muscle cells, strongly suggestive of rhabdomyosarcoma of the liver. Elevated levels of alpha-fetoprotein in the serum led us to examine the liver tumour closely in multiple sections, which disclosed a hepatocellular carcinoma component measuring 2 cm in diameter within the massive tumour. Immunohistochemically, the hepatocellular carcinoma cells were alpha-fetoprotein positive. There was neither a tumour capsule, nor distinct demarcation, and cytokeratin-positive clusters of undifferentiated cells were intermingled with the hepatocellular carcinoma and rhabdomyosarcoma at the border. The invading tumour outside the liver and metastatic tumours were pure rhabdomyosarcomas. It is suggested that the present case should be diagnosed as rhabdomyosarcoma transformed from hepatocellular carcinoma.

Expression of co-stimulatory factor B7-2 on the intrahepatic bile ducts in primary biliary cirrhosis and primary sclerosing cholangitis: an immunohistochemical study

Co-stimulatory factors B7-1 (CD80) and B7-2 (CD86) and their ligands, including CD28, are important for the efficient presentation and persistence of an antigen-specific immune reaction. Hitherto, there has been a paucity of data on the roles of such co-stimulatory factors in immune-mediated biliary diseases. In this investigation, the hepatic immunohistochemical expression of B7-1 and B7-2 has been studied, with emphasis on intrahepatic biliary epithelia, using wedge biopsies from 22 patients with primary biliary cirrhosis (PBC), seven with primary sclerosing cholagitis (PSC), and, as controls, eight cases of extrahepatic biliary obstruction, eight of chronic viral hepatitis C, and three histologically normal livers. In 10/22 (45 per cent) patients with PBC and 3/7 (43 per cent) patients with PSC, B7-2, but not B7-1, was expressed on the epithelial cells of small intrahepatic bile ducts and bile ductules. This expression was manifest as diffuse but variable cytoplasmic staining. Such B7-2-positive bile ducts were not seen in controls. Positive staining was found only in the early stage of PBC and PSC. In PBC and PSC, almost all lymphocytes in the portal tracts, including those around the damaged bile ducts, were positive for CD28, a ligand of B7-2. These results suggest that B7-2 expression on biliary epithelial cells is involved in antigen presentation and perhaps in bile duct destruction in PSC and PBC.

Expression of interferon alpha/beta receptor in the liver of chronic hepatitis C patients

Interferon (IFN) demonstrates antiviral activity by binding to receptors on the cell surface. Expression of the IFN receptor in hepatocytes may be directly associated with a hepatitis C virus (HCV) infection and the response to IFN therapy. A competitive PCR method was developed to measure IFN alpha/beta (alphabeta) receptor mRNA in liver samples obtained by needle biopsy. Thirty-one patients with chronic hepatitis C (21 without cirrhosis, 10 with cirrhosis) and six normal subjects were used. Eighteen of the 21 patients without cirrhosis received the IFN therapy. Competitive PCR was carried out using IFN alphabeta receptor gene-specific primers and a specific competitor. Expression of the receptor was detected in all liver samples. There was no association between the expression level and serum alanine aminotransferase level, serum (2'-5') oligo (A) synthetase level, amount of serum HCV RNA, or HCV genotype. The expression level in patients with chronic hepatitis was significantly higher than that in normal livers (P < 0.05) and in cirrhotic livers (P< 0.01). Seven of the 18 patients treated with IFN demonstrated a sustained response to IFN (sustained responders), and the remaining 11 did not (nonsustained responders). The expression level of IFN alphabeta receptor mRNA in the sustained responders was significantly higher than that in the nonsustained responders (P< 0.01). Thus, the expression of IFN alphabeta receptor mRNA may be one of the host factors influencing the response to IFN therapy.

A case of progressive multiple focal nodular hyperplasia with alteration of imaging studies

Focal nodular hyperplasia (FNH) of the liver is a lesion characterized by a well circumscribed region of hyperplastic liver tissue with stellate fibrosis. The pathogenesis of the lesion is unknown but various authors consider that FNH may be a response to a preexisting vascular abnormality. We experienced a case of progressive multiple FNH, in which the hemodynamic change as shown by imaging modalities, may support this hypothesis. The patient, a 38-yr-old woman, was found by chance to have multiple portal venous shunts and multiple FNH in both lobes of her liver. Because of their benign characteristics, we followed the nodules periodically without any special treatment. After about 4 yr, the nodules increased both in size and number. In addition, digital subtraction angiography showed that the diameter of the artery had become larger. The hemodynamic change revealed by imaging studies in this case supports the hypothesis that one of the pathogens of FNH is a secondary hepatocellular response to arterial hyperperfusion caused by some vascular malformations.

Expression of interferon alpha/beta receptor in the liver of chronic hepatitis C patients

Interferon (IFN) demonstrates antiviral activity by binding to receptors on the cell surface. Expression of the IFN receptor in hepatocytes may be directly associated with a hepatitis C virus (HCV) infection and the response to IFN therapy. A competitive PCR method was developed to measure IFN alpha/beta (alphabeta) receptor mRNA in liver samples obtained by needle biopsy. Thirty-one patients with chronic hepatitis C (21 without cirrhosis, 10 with cirrhosis) and six normal subjects were used. Eighteen of the 21 patients without cirrhosis received the IFN therapy. Competitive PCR was carried out using IFN alphabeta receptor gene-specific primers and a specific competitor. Expression of the receptor was detected in all liver samples. There was no association between the expression level and serum alanine aminotransferase level, serum (2'-5') oligo (A) synthetase level, amount of serum HCV RNA, or HCV genotype. The expression level in patients with chronic hepatitis was significantly higher than that in normal livers (P < 0.05) and in cirrhotic livers (P< 0.01). Seven of the 18 patients treated with IFN demonstrated a sustained response to IFN (sustained responders), and the remaining 11 did not (nonsustained responders). The expression level of IFN alphabeta receptor mRNA in the sustained responders was significantly higher than that in the nonsustained responders (P< 0.01). Thus, the expression of IFN alphabeta receptor mRNA may be one of the host factors influencing the response to IFN therapy.

Expression of co-stimulatory factor B7-2 on the intrahepatic bile ducts in primary biliary cirrhosis and primary sclerosing cholangitis: an immunohistochemical study

Co-stimulatory factors B7-1 (CD80) and B7-2 (CD86) and their ligands, including CD28, are important for the efficient presentation and persistence of an antigen-specific immune reaction. Hitherto, there has been a paucity of data on the roles of such co-stimulatory factors in immune-mediated biliary diseases. In this investigation, the hepatic immunohistochemical expression of B7-1 and B7-2 has been studied, with emphasis on intrahepatic biliary epithelia, using wedge biopsies from 22 patients with primary biliary cirrhosis (PBC), seven with primary sclerosing cholagitis (PSC), and, as controls, eight cases of extrahepatic biliary obstruction, eight of chronic viral hepatitis C, and three histologically normal livers. In 10/22 (45 per cent) patients with PBC and 3/7 (43 per cent) patients with PSC, B7-2, but not B7-1, was expressed on the epithelial cells of small intrahepatic bile ducts and bile ductules. This expression was manifest as diffuse but variable cytoplasmic staining. Such B7-2-positive bile ducts were not seen in controls. Positive staining was found only in the early stage of PBC and PSC. In PBC and PSC, almost all lymphocytes in the portal tracts, including those around the damaged bile ducts, were positive for CD28, a ligand of B7-2. These results suggest that B7-2 expression on biliary epithelial cells is involved in antigen presentation and perhaps in bile duct destruction in PSC and PBC.

Inhibition of bFGF activity by complement C1s: covalent binding of C1s with bFGF

The first complement component C1s formed large aggregates with bFGF when bFGF and C1s were incubated at 37 degrees C overnight. Under non-reducing conditions, a part of the aggregates did not penetrate into 5% polyacrylamide gel in the presence of SDS, and the rest penetrated into 5% gel but not into 12% gel. The aggregates were dissociated into monomers by reducing with 2-mercaptoethanol. Both active and inactive C1s formed aggregates with bFGF. In addition, a portion of bFGF was degraded by active C1s but not by inactive C1s. Aggregates were not formed when 2-mercaptoethanol (2 mM) was added to the incubation mixture. After the incubation with C1s the growth-stimulating activity of bFGF was measured by using human umbilical vein endothelial cells (HUVEC) as indicator cells. The aggregate formation between C1s and bFGF significantly reduced the activity of bFGF.

Gastrointestinal amyloidosis secondary to hypersensitivity vasculitis presenting with intestinal pseudoobstruction

A 22-year-old woman developed sudden hepatic encephalopathy and severe intestinal bleeding. She was diagnosed with acute fatty liver and hypersensitivity vasculitis and was successfully treated with whole plasma exchange, methylprednisolone pulse therapy, and transcatheter arterial embolization. Twenty-seven months later, she began complaining of lower abdominal fullness, tenderness, and nausea and vomiting. Histologic examination showed that she had developed gastrointestinal and renal amyloidosis with intestinal pseudoobstruction and proteinuria. The immunohistochemical study of the stomach, rectum, and kidney with anti-amyloid A fluorescent antibody showed that the systemic amyloid deposit was secondary to her underlying disease. This is the first report of amyloidosis occurring secondary to hypersensitivity vasculitis.

Genetic variation and population structure of the Japanese sika deer (Cervus nippon) in Hokkaido Island, based on mitochondrial D-loop sequences

Mitochondrial DNA (mtDNA) D-loop region sequences (602 bp) from 141 samples of the sika deer Cervus nippon collected from Hokkaido Island of Japan were investigated to elucidate population genetic structure. All animals possessed seven repeat units (38 or 39 bp each) in the sequences. Comparison of the 602-bp sequences showed four sites of transitional mutations (A<-->G or C<-->T). Based on combination of the substitutions, six D-loop haplotypes (a-f types) were identified in the Hokkaido population, suggesting the occurrence of at least six maternal lineages. Distribution maps of the haplotypes constructed using the Geographic Information System showed that the distribution of the major three types differed from haplotype to haplotype. In particular, distribution of the major three types (a-, b-, and c-types) almost overlapped with three main areas of coniferous forests in Hokkaido. These results suggest that expansion of the sika deer population could have occurred through the habitat of coniferous forests after the historical bottleneck in Hokkaido.

Suppression of apoptosis by inhibition of phosphatidylcholine-specific phospholipase C in vascular endothelial cells

In order to clarify the role of phosphatidylcholine-specific phospholipase C (PC-PLC) in the regulation of apoptosis in vascular endothelial cells (VEC), we investigated the effects of D609, a specific inhibitor of PC-PLC, on apoptosis that was induced by deprivation of fibroblast growth factor (FGF) and serum and also by rattlesnake venom. The early morphological changes (detachment of cells from dishes) and the fragmentation of DNA, which is a specific feature of apoptotic cell death, were clearly inhibited by D609 in these two apoptosis-inducing systems. Moreover, the production of diacylglycerol (DAG), which was stimulated in apoptotic VEC, was suppressed by D609. The effects of D609 on the activity of PC-PLC and on apoptosis of VEC were dose-dependent. Our results indicate that PC-PLC is involved in the apoptosis-inducing signal pathway in VEC and, that DAG, produced from phosphatidylcholine (PC), might be an important mediator in this signal-transduction pathway. Our results also suggest that rattlesnake venom, a strong promoter of apoptosis in VEC, might induce apoptosis by stimulating PC-PLC and, furthermore, that PC-PLC might play a significant role in anchorage-dependent signal transduction in VEC.

Increased hepatocyte growth factor production by aging human fibroblasts mainly due to autocrine stimulation by interleukin-1

Hepatocyte growth factor (HGF), also known as scatter factor is a pleiotropic factor that is mainly produced by mesenchymal cells and acts on cells of epithelial origin which express the HGF receptor c-Met. Here we demonstrate that production of HGF by human embryonic lung fibroblasts increased sharply after about 70% completion of their lifespan in culture, which is regulated at the transcriptional level. In addition, human skin fibroblasts from old donors, over 80 years, also produced more HGF than cells from young and middle-aged donors. The increased production of HGF by aging fibroblasts from human embryonic lung tissue is mainly due to autocrine stimulation by interleukin-1.

TMIG-2DPAGE: a new concept of two-dimensional gel protein database for research on aging

Cellular proteins of a normal human diploid fibroblast line (TIG-3) at various stages of replicative aging were resolved by horizontal isoelectric focusing on an immobilized pH gradient, followed by vertical sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE). Spot proteins were visualized by silver staining and quantitated by image processing. All corresponding spots were matched among two-dimensional gel images, and variation profiles in relative abundance of individual proteins during in vitro aging were classified into five categories, i.e., (i) increase, (ii) decrease, (iii) increase followed by decrease, (iv) decrease followed by increase, and (v) irregular or nonsignificant variation. The new concept of the Tokyo Metropolitan Institute of Gerontology two-dimensional gel protein database (TMIG-2DPAGE) was prepared from the above data to support research on cellular aging. The database was put on our World Wide Web home page at the URL of http://www.tmig.or.jp/2D/ to allow free access through the Internet. The individual protein data entries were linked to the standard spot protein map of the two-dimensional gel image in order to be accessible by clicking the mouse on it.

Mutation and formation of methyl- and hydroxylguanine adducts in DNA caused by N-nitrosodimethylamine and N-nitrosodiethylamine with UVA irradiation

Previously we reported that when Escherichia coli was treated with N-nitrosodialkylamine under irradiation with near UV light, mutagenesis of the bacteria took place: there was no requirement for metabolic activation. We have now studied the spectra of mutations caused by N-nitrosodimethylamine (NDMA) and N-nitrosodiethylamine (NDEA) with UVA (320-400 nm) irradiation, using standard tester strains for identifying types of mutations. Induced mutations by NDMA + UVA were the transition GC-->AT and transversions GC-->CG, GC-->TA and AT-->TA. NDEA + UVA induced mainly the GC-->CG transversion. In both cases no frameshift mutations were observed. When O6-alkylguanine-DNA alkyltransferase-deficient strains of E. coli and Salmonella typhimurium were used, the mutation levels with both NDMA + UVA and NDEA + UVA became remarkably higher than those observed with the proficient strains. We measured the O6-methylguanine (O6-meG) level in calf thymus DNA treated with NDMA + UVA. The O6-meG level was increased as a function of NDMA concentration and irradiation time. We also detected N7-methylguanine in DNA treated with NDMA + UVA. In our previous work we found formation of 8-oxodeoxyguanosine (8-oxodG) in DNA treated with N-nitrosomorpholine + UVA. The 8-oxodG/dG ratio in DNA treated with NDMA + UVA increased up to 42-fold over that of the untreated control and that in DNA treated with NDEA + UVA increased up to 67-fold. 8-OxodG formation was not affected by replacing H2O in the reaction mixture with D2O, suggesting that singlet oxygen is not the rate limiting factor in this photoactivation. We conclude that both alkylation and oxidation are involved in mutations induced by NDMA + UVA and NDEA + UVA.

Clinicopathological study of primary biliary cirrhosis negative for antimitochondrial antibodies

Primary biliary cirrhosis (PBC) is characterized by the occurrence of antimitochondrial antibodies (AMA) and the progressive destruction of intrahepatic bile ducts, followed by biliary cirrhosis. However, there are about 5% of PBC patients who show clinicopathological features of PBC but are negative for AMA. In this study, clinicopathological features, as well as antibody reactivity against recombinant (r)-mitochondrial polypeptides, were examined in 30 AMA negative PBC patients and 38 AMA positive PBC patients, in whom the presence of AMA had been determined by indirect immunofluorescence (IF). There were few differences in the clinical and serological features between both groups. Histopathologic features, including staging, bile duct lesions and granuloma, were also similar in both groups. Among the 30 IF-tested AMA negative patients, 29 were also negative against beef heart mitochondrial proteins, but 24 reacted to one or more of the following r-polypeptides, as determined by immunoblotting: E1 alpha of pyruvate dehydrogenase complex, the E2 subunit of pyruvate dehydrogenase complex, and the branched-chain 2-oxo-acid dehydrogenase complex. The remaining six AMA-negative patients were asymptomatic, and histologically resembled having stage 1 of the disease, with relatively mild lymphocytic piecemeal necrosis. One case was positive for anti-smooth muscle antibody. The other clinicopathological features of these patients were similar to those of other AMA negative patients. The present study found that a majority of the AMA-negative patients fulfilling other clinicopathological criteria of PBC, had features similar to the AMA-positive PBC patients, and that a majority of IF AMA-negative patients were positive for r-polypeptides of the 2-oxo-acid dehydrogenase complex. It seems that nearly all the AMA negative patients possess a broad spectrum of antibody profile of AMA, in addition to clinicopathological and serological features.

B7-2 positive cells around interlobular bile ducts in primary biliary cirrhosis and chronic hepatitis C

Bile duct damage in patients with chronic hepatitis C (hepatitis-associated bile duct lesion) as well as that in patients with primary biliary cirrhosis (PBC; chronic non-suppurative destructive cholangitis), may be causally related to immunological assaults. Efficient antigen presentation is known to require the provision of a costimulatory signal which is dependent on the CD28 on T cell surfaces, and that at least two molecules, B7-1 and B7-2, work as costimulatory ligands for CD28. In this study, we examined immunohistochemically, the expression of B7-2 in portal tracts of liver biopsy specimens obtained from 75 patients with chronic hepatitis C who had hepatitis-associated bile duct lesions, and from 63 PBC patients with chronic non-suppurative destructive cholangitis. B7-2 positive cells were recognizable as large mononuclear cells scattered in portal tracts. Some of these cells showed a dendritic cell-like appearance. B7-2 positive cells were observed more frequently (41%) in PBC liver specimens than in chronic hepatitis C specimens (17%, P < 0.05). In PBC livers, such cells were preferentially observed around the damaged bile duct with a few located in the biliary epithelial layer. There was no such finding in chronic hepatitis C livers. The frequency and density of B7-2 positive cells in the liver specimens tended to decrease according to the stage of PBC (45% in stages 1 and 2, and 33% in stages 3 and 4; P = 0.10), whereas with chronic hepatitis C, no such tendency was observed. These findings suggest that B7-2 positive cells may play a role in the bile duct lesions that appear in the early histological stages of PBC and that the immunological mechanisms of bile duct damage, particularly of antigen presentation and B7-2 expression, differ between PBC and chronic hepatitis C.

Purification of a vascular apoptosis-inducing factor from hemorrhagic snake venom

Hemorrhagic snake venom induces apoptosis in vascular endothelial cells specifically. We report here the purification of an apoptosis-inducing factor from the venom of the rattlesnake Crotalus atrox. The purified factor was a homodimeric protein with a molecular mass of 110 kD and an isoelectric point of 8.5. When exposed to the factor, vascular endothelial cells in culture died, with the characteristic features of apoptosis, such as fragmentation of cells and cleavage of DNA into fragments that yielded a characteristic ladder pattern upon electrophoresis. The activity seemed to be specific to endothelial cells. This factor may prove to be a useful tool for studies of the molecular mechanisms of vascular apoptosis.

Hemosiderin deposition in portal endothelial cells is a histologic marker predicting poor response to interferon-alpha therapy in chronic hepatitis C

Interferon (IFN)-alpha is regarded as an efficient therapy for chronic hepatitis C, despite the fact that less than 50% of patients receiving IFN-alpha are known to show an initial biochemical response, and several adverse reactions related to this therapy are becoming a serious clinical problem. For a more efficient and safer treatment of IFN-alpha, several pretreatment factors to predict a favorable or unfavorable response to IFN-alpha therapy are now being evaluated, such as hepatitis C virus (HCV)-RNA levels in serum and the genotypes of HCV. Recently, the hepatic iron concentration has been reported to influence the outcome of IFN-alpha therapy for chronic viral hepatitis. In the present study, whether hemosiderin deposition in liver is a histologic predictor of response to IFN-alpha therapy was evaluated, as well as which anatomical location showing the hemosiderin deposition was more closely related to the response to this therapy. Two factors, high titer of HCV-RNA in serum and hemosiderin deposition in portal endothelial cells, were found to be predictable factors of poor response to IFN-alpha therapy, and these two factors were found to be related to each other. Results showed that the hemosiderin deposition in portal endothelial vessels is an easily evaluable histologic finding, and clinicians and histopathologists are encouraged to use this finding when selecting patients with chronic hepatitis C suitable for IFN-alpha therapy.