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Biomedical subjects

K Mitamura

Publications and source records attributed to K Mitamura.

At least 19 recordsLinked to original sources

Gas chromatography and high-performance liquid chromatography of natural steroids.

This review article underlines the importance of gas chromatography (GC), high-performance liquid chromatography (HPLC) and their hyphenated techniques using mass spectrometry (MS) for the determination of natural steroids, especially in human biological fluids. Steroids are divided into eight categories based on their structures and functions, and recent references using the above methodologies for the analysis of these steroids are cited. GC and GC-MS are commonly used for the determination of volatile steroids. Although HPLC is a widely used analytical method for the determination of steroids including the conjugated type in biological fluids, LC-MS is considered to be the most promising one for this purpose because of its sensitivity, specificity and versatility.

Chromatography, Gas↗

The presence of a newly identified infectious agent (SEN virus) in patients with liver diseases and in blood donors in Japan.

The existence of the newly discovered SEN virus (SENV) was investigated in 379 Japanese patients with liver diseases and in 277 blood donors, to determine whether SENV is associated with non-A-E hepatitis. SENV DNA was detected by seminested polymerase chain reaction, with primers directed to 2 SENV strains: SENV-H and SENV-D. SENV was detected in 7 (32%) of 22 patients with fulminant hepatitis, in 15 (17%) of 86 patients with acute hepatitis, in 38 (27%) of 139 patients with chronic hepatitis, in 29 (31%) of 93 patients with liver cirrhosis, in 5 (33%) of 15 patients with autoimmune hepatitis, in 11 (46%) of 24 patients with primary biliary cirrhosis, and in 27 blood donors (10%). Infection occurred more frequently in patients with liver diseases than in blood donors; however, there were no significant differences in SENV-positive rates between patients with non-A-C hepatitis and those with acute or chronic hepatitis due to known hepatitis virus or nonviral liver disease. This study did not suggest SENV as a possible causative agent of non-A-C hepatitis.

Adolescent↗

Prognostic value of p53 mutations in patients with locally advanced esophageal carcinoma treated with definitive chemoradiotherapy.

PURPOSE: A significant correlation has been found between p53 mutation and response to chemotherapy or radiotherapy. To determine the prognostic value of p53 mutation in patients with locally advanced esophageal carcinoma treated with definitive chemoradiotherapy, p53 mutation was analyzed using the biopsied specimens taken for diagnosis. METHODS: Concurrent chemoradiotherapy was performed for 40 patients with severe dysphagia caused by esophageal squamous cell carcinoma associated with T3 or T4 disease. Chemotherapy consisted of protracted infusion of 5-fluorouracil, combined with an infusion of cisplatinum. Radiation treatment of the mediastinum was administered concomitantly with chemotherapy. The p53 gene mutation was detected by fluorescence-based polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) methods. DNA sequences were determined for DNA fragments with shifted peaks by SSCP methods. RESULTS: Of the 40 patients, 15 had T3 disease and 25 had T4 disease; 11 patients had M1 lymph node (LYM) disease. Of the 40 patients, 13 (33%) achieved a complete response. The median survival time was 14 months, and the 2-year survival rate was 20%. Among the 40 tumor samples, p53 mutation was detected in 24 tumors (60%). The survival rate in the 24 patients with p53 mutation did not differ significantly from that in the 16 patients without p53 mutation. In contrast, the 15 patients with T3 disease survived longer than the 25 patients with T4 disease (P = 0.016); however, the survival rate in the 11 patients with M1 LYM disease did not differ significantly from that in the 29 patients without M1 LYM disease. CONCLUSION: Concurrent chemoradiotherapy is potentially curative for locally advanced esophageal carcinoma, but p53 genetic abnormality has no impact on prognosis.

Aged↗

A case of autoimmune hepatitis with a high titer of antimitochondrial antibody and normal gamma-globulinemia.

We report here a patient with chronic active hepatitis who had no markers for hepatitis viruses and no hyper-gamma-globulinemia, but had high titers of antimitochondrial antibody. Serum levels of alkaline phosphatase were normal, and antinuclear antibody, antismooth muscle antibody, and antiliver kidney microsome antibody tested negative. The titers of antimitochondrial antibody exceeded 1:640, and the positivity for anti-M2 was ascertained by using both ELISA and immunoblot with beef-heart mitochondria and a recombinant pyruvate dehydrogenase E2 subunit as antigens. This patient responded to ursodeoxycholic acid (UDCA) therapy in the beginning, but her hepatitis flared up during UDCA therapy. In contrast, she responded completely to corticosteroid therapy. The clinical course and histological findings of this patient strongly suggest that this patient has autoimmune hepatitis.

Aged↗

Acquisition of susceptibility to hepatitis C virus replication in HepG2 cells by fusion with primary human hepatocytes: establishment of a quantitative assay for hepatitis C virus infectivity in a cell culture system.

Hepatitis C virus (HCV) replicates in human and chimpanzee hepatocytes. To characterize the nature of HCV and evaluate antiviral agents, the development of an HCV replication system in a cell culture is essential. We developed a cell line derived from human hepatocytes by fusing them with a hepatoblastoma cell line, HepG2, and obtained several clones. When we tested the clones for their ability to support HCV replication by nested RT-PCR, we found 1 clone (IMY-N9) that was more susceptible to HCV replication than HepG2. The negative-strand HCV RNA was detected in IMY-N9 by strand-specific RT-PCR, and viral RNA was identified in culture supernatant during the culture. Then we monitored HCV RNA titers in IMY-N9 and HepG2, respectively, by real-time detection PCR throughout the culture. A significant increase in the HCV RNA titer was observed only in IMY-N9. Serial passages of HCV culture supernatant were shown in the culture system. Furthermore, we tested several infectious materials for viral infectivity by monitoring HCV RNA titers and/or 50% tissue culture infectious dose (TCID50) of HCV on IMY-N9. In each material, HCV showed various growth patterns and a different TCID50 even though the PCR titer in each material was identical. The results showed that HCV in each material served various growth patterns and different TCID50 even though PCR titer in each material was identical. This cell line is useful for estimating viral activity and for studying cellular factors that may be necessary to HCV replication in human hepatocytes.

Cell Fusion↗

Validation of color Doppler EUS for azygos blood flow measurement in patients with cirrhosis: application to the acute hemodynamic effects of somatostatin, octreotide, or placebo.

BACKGROUND: Color Doppler EUS (CD-EUS) allows minimally invasive measurement of azygos blood flow (AzBF) in portal hypertension, but further validation of the method is needed. Because a limited number of patients has been studied, the acute hemodynamic effects of somatostatin and octreotide on AzBF and gastric mucosal perfusion are poorly defined in portal hypertension. METHODS: A double-blind hemodynamic study was designed to assess rapid changes in AzBF over a 60-minute period after intravenous administration of somatostatin, octreotide, and placebo in 30 stable patients with biopsy-proven cirrhosis. AzBF was measured by using both CD-EUS and the invasive thermal dilution technique in the first 10 patients (phase 1). Then, with CD-EUS alone, the hemodynamic study was extended to a further 20 patients (phase 2). In addition, gastric mucosal perfusion changes were assessed by using laser Doppler flowmetry at endoscopy. RESULTS: In phase 1, the 2 methods for AzBF measurement showed significant correlations both for baseline values (r = 0.685) and for AzBF changes over 60 minutes after drug administration (r = 0.733). In phase 2, a reduction was observed in AzBF 10 minutes after octreotide or somatostatin administration (-47% and -23%, p < 0.0001 vs. placebo, p = 0.058 vs. placebo, respectively). After 60 minutes of somatostatin infusion, AzBF increased 27% over placebo values (p < 0.04). Gastric mucosal perfusion was transiently reduced 5 minutes after octreotide or somatostatin (-21% and -32%, respectively, p < 0.02 vs. placebo). CONCLUSIONS: This is the first study to validate CD-EUS AzBF measurement with reference to the invasive thermodilution technique in cirrhosis. It confirmed the transient effects of somatostatin and octreotide on both AzBF and gastric mucosal perfusion. In addition, a significant rebound phenomenon after 60 minutes of continuous intravenous somatostatin infusion was observed.

Aged↗

Decreased expression of signaling lymphocytic-activation molecule-associated protein (SAP) transcripts in T cells from patients with rheumatoid arthritis.

The function of Epstein-Barr virus (EBV)-specific cytotoxic T cells is disturbed in rheumatoid arthritis (RA) patients but the mechanism for this disturbance has remained unknown. In a recent study searching for the causative gene of X-linked lymphoproliferative syndrome, the gene possibly linked to EBV-specific cytotoxic T cells or NK cell-mediated cytotoxic activity to EBV-infected cells was discovered, and its product is now referred to as signaling lymphocytic-activation molecule-associated protein (SAP) or Src homology 2 domain-containing protein (SH2D1A). In the present study, we attempted to investigate the involvement of the SAP gene in RA using a quantitative real-time PCR; the expression level of SAP transcripts in peripheral leukocytes or T cells was examined for patients with RA. The expression level of SAP transcripts in peripheral leukocytes of 21 RA patients was significantly lower than that of 13 normal individuals (P = 0.0007), four patients with palindromic RA, 11 with inactive systemic lupus erythematosus (SLE) or 17 with chronic renal diseases. The decreased expression of SAP transcripts in RA patients was also observed in peripheral CD2(+) T cells compared with normal individuals. There was no mutation in the coding region of SAP cDNAs derived from peripheral leukocytes of five RA patients. The decreased expression of SAP transcripts in peripheral leukocytes or T cells of RA patients might lead to the failure of the immune system to eliminate the EBV-infected synovial lining cells in joints of RA patients. Our findings have suggested that decreased expression of the SAP gene might be involved in the onset or progress of RA.

Antigens, CD↗

[Evaluation of immunochromatography based rapid detection kit of rotavirus and adenovirus].

We investigated the usefulness of Rapidtesta Rota-Adeno (Daiichi Pure Chemicals Co., Ltd., Japan) for rapid detection of group A rotavirus and adenovirus simultaneously using immunochromatography with clinical samples. In investigation of the reaction of the kit to 5 strains of group A rotavirus, 13 strains of adenovirus and other intestinal viruses, specific lines were formed in red to group A rotavirus and blue to adenovirus. No cross reaction was observed with other intestinal virus. In measurement of detection limit, group A rotavirus (SA11) was detected at 10(4.4)TCID50/ml, serotype 3 adenovirus at 10(4.45)TCID50/ml. The detection limit of the kit was similar to other immunochromatographic assay or enzyme immnoassay kits and approximately 10 times higher than that of kits using latex agglutination test. In comparison with other testing kits in clinical samples, the concordance with other immunochromatographic assay was 99.2% (121/122) in group A rotavirus and 98.6% (138/140) in adenovirus. The rate of concordance with latex agglutination test kit was 94.5% (69/73) in group A rotavirus and 92.3% (84/91) in adenovirus. The kit had high rates of concordance with other immunochromatographic assay kits and higher virus detection rates than those of latex agglutination test kits. Rapidtesta Rota-Adeno is able to detect group A rotavirus and adenovirus simply and rapidly. In addition, the two kinds of virus can be easily differentiated by color difference in reaction lines, suggesting that the kit is useful in clinical diagnosis.

Adenoviridae↗

[Clinical evaluation of an immunochromatography test for rapid diagnosis of influenza].

We evaluated a rapid diagnostic kit that detects influenza type A and B viral antigens by immunochromatography, Quick Vue Influenza Test (Quidel Corp., San Diego, CA, USA), with 425 specimens collected from patients with influenza-like symptoms at three hospitals between January and March 2001. The specimens included 184 nasal aspirates, 140 nasal swabs, and 101 throat swabs. The test correctly identified 179 of the 204 culture positive specimens and 203 of the 221 culture negative specimens; the sensitivity and specificity compared with the culture were 87.7% and 91.9%, respectively. The sensitivity of the test was 92.6% (112/121) for nasal aspirates, 83.7% (41/49) for nasal swabs, and 76.5% (26/34) for throat swabs, which is similar to the results for conventional rapid enzyme immunoassay kits for influenza virus infection. The sensitivity and specificity of the QuickVue Influenza Test were equivalent to those of Flu OIA (BioStar, Inc., Boulder, CO, USA), with the agreement of 84.2%. Although the QuickVue Influenza Test does not differentiate between influenza A and B viruses, the easy-to-use kit detects both types in the physician's office, allowing physicians to make a decision on prescription of neuraminidase inhibitor therapy during the initial visit.

Evaluation Studies as Topic↗

[Evaluation of immunochromatography method for rapid detection of influenza A and B viruses].

We have evaluated a new rapid detection kit for influenza A and B viruses, known as the QuickVue Influenza test (Quidel Coporation, USA); which is based on immunochromatography using virus isolates and clinical specimens. Twelve strains of influenza A and B were tested for evaluate the reactivity and detection limits of this test. The QuickVue Influenza test showed a positive result for all twelve strains of influenza virus and a negative result for fourteen different kinds of other respiratory viruses. The detection limits for six strains were 5 to 30 pfu/ml for a cell culture, 1.0 x 10(3) to 6.0 x 10(4) pfu/ml for 1st PCR, 1 to 50 pfu/ml for nested PCR, 3.0 x 10(5) to 6.0 x 10(5) pfu/ml for the QuickVue Influenza test, 1.5 x 10(5) to 1.0 x 10(6) pfu/ml for the Directigen Flu A, and 7.5 x 10(5) to 5.0 x 10(6) pfu/ml for the FLU OIA. Furthermore, the QuickVue Influenza test were clinically evaluated using 92 throat swab specimens collected from patients with influenza-like illnesses. By cell culture, influenza viruses were detected in 49 of the 92 specimens (AH1N1: 20, AH3N2: 7, B: 22); the titers of the influenza viruses were between 2.5 pfu/ml and 7.0 x 10(5) pfu/ml. Compared to cell culture, the QuickVue Influenza test showed a sensitivity of 75.5%, a specificity of 93.0%, a positive predictive value of 92.5%, a negative predictive value of 76.9%, and an efficiency value of 83.7%. On the other hand, influenza viruses were detected in 54 of the 92 specimens (AH1N1: 19, AH 3N2: 10, B: 25) by RT-PCR. Compared to RT-PCR, the QuickVue Influenza test showed a sensitivity of 72.2%, a specificity of 97.4%, a positive predictive value of 97.5%, a negative predictive value of 71.2%, and an efficiency value of 82.6%. Overall, only one throat swab specimen produced a false positive result using the QuickVue Influenza test; thus, this test appears to have a high specificity. We conclude that the QuickVue Influenza test is a simple one-step test with a sensitivity and specificity equivalent to those of other conventional diagnostic kits. The test is useful and suitable for the diagnosis of influenza and for identifying influenza patients requiring antiviral therapy.

Influenza A virus↗

Frequent down-regulation of E-cadherin by genetic and epigenetic changes in the malignant progression of hepatocellular carcinomas.

E-cadherin mediates cell-cell adhesion by associating with catenins. Loss of E-cadherin function by genetic or epigenetic alteration of the E-cadherin gene (CDH1) leads to tumorigenesis. To study the involvement of E-cadherin dysfunction in liver tumorigenesis, we examined the allelic loss and methylation of 5'-CpG sites of CDH1 in hepatocellular carcinomas (HCCs). Loss of heterozygosity (LOH) of CDH1 and adjacent 16q22-23 loci was observed in 13 of 30 (43%) HCCs. Methylation of the 5'-CpG of CDH1 was analyzed by Southern blot hybridization, and hypermethylation was observed in 8 of the 24 (33%) HCCs examined. The amount of E-cadherin mRNA was analyzed by RNase protection assay, and a decrease in E-cadherin mRNA was observed in 10 of the 23 cases examined. A reduction in E-cadherin was found in 10 of 21 HCCs using immunoblot analysis. The amount of E-cadherin was comparable to that of E-cadherin mRNA. Down-regulation of E-cadherin was common in cases with LOH but rare in cases with methylated promoter. These results suggest that hypermethylation of the CDH1 promoter is present in a small cell population in the tumor, thus the methylation status is liable to vary according to individual cell condition. Hypermethylation was observed in early stage HCCs, whereas LOH was found frequently in more malignant tumors. Down-regulation of E-cadherin is closely related to the progression of HCCs and is stably induced by LOH of CDH1.

Blotting, Southern↗

[A case of esophageal carcinoma with multiple liver metastases successfully treated with nedaplatin (NDP) and 5-fluorouracil (5-FU) combined with radiotherapy].

A 78-year-old male patient had esophageal carcinoma with multiple liver metastases. Chemoradiotherapy was performed. The chemotherapy consisted of protracted infusion of 5-fluorouracil (5-FU), combined with infusion of nedaplatin (NDP). Radiation of the mediastinum was administered concomitantly with chemotherapy. The patient showed a complete response (CR) of the primary lesion and a partial response (PR) of the liver metastasis for 11 months. Since liver metastasis recurred after initial treatment, chemotherapy consisting of NDP infusion combined with vindesine sulfate (VDS) infusion was performed. The patient again showed PR. Grade 3 leukocytopenia occurred during treatment, but there were no major toxicities such as thrombocytopenia, nausea, renal dysfunction or esophagitis. Survival time was one year and 7 months. In conclusion, concurrent chemoradiotherapy including NDP is effective and safe for patients with esophageal carcinoma accompanied by multiple liver metastasis. This nonsurgical approach may be an option for standard care in such cases.

Aged↗

Studies on neurosteroids XII. Determination of enzymatically formed catechol estrogens and guaiacol estrogens by rat brains using liquid chromatography-mass spectrometry-mass spectrometry.

Enzymic formations of catechol- and guaiacol-estrogens by rat brains have been investigated using classical- and catechol-estrogens as substrates, respectively. The incubation mixtures were pretreated with liquid-liquid and/or solid-phase extraction, and the products were identified by comparison with authentic samples using liquid chromatography-mass spectrometry (-mass spectrometry) [LC-MS (-MS)]. The enzymic activities were also determined by measuring the formed products with LC-MS.

Animals↗

Detection of mutation of the p53 gene with high sensitivity by fluorescence-based PCR-SSCP analysis using low-pH buffer and an automated DNA sequencer in a large number of DNA samples.

Detection of mutations in genes responsible for hereditary diseases or tumors is important clinically. It is necessary to establish a simple technique for screening mutations in large numbers of samples. The polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) method has proved to be a useful technique for analyzing mutations or DNA polymorphisms. Non-radioisotopic versions using fluorescent dye and an automated DNA sequencer have also been exploited to extend this technique into the clinical field. We have examined mutations of exons 5-9 of the p53 gene in 112 colorectal, 28 esophageal and 33 hepatocellular carcinomas by fluorescence-based PCR-SSCP (F-SSCP) under various conditions. We found 64 types of mutations in 63, 17 and 12 cases of colon, esophageal and hepatocellular carcinomas by F-SSCP. We determined the sequence of all samples, and confirmed that all mutations were successfully detected by F-SSCP. With the low-pH buffer system, 61 types of mutants were detected, while 51 types were detected by TBE and 57 types were detected by TBE with glycerol gel. The polyacrylamide gel in TME or TBE without glycerol was tough and could be used repeatedly, but the glycerol containing gel was fragile and could not stand repeated use. Thus, use of a low-pH buffer in the electrophoresis of F-SSCP is simpler and better at detecting mutations than the conventional TBE buffer system. We believe that low-pH F-SSCP analysis is an efficient and powerful technique for examination of a large number of samples, in particular clinical specimens obtained by biopsy or surgery.

DNA Mutational Analysis↗

A possible role for Ca(2+)/calmodulin-dependent protein kinase IV during pancreatic acinar stimulus-secretion coupling.

Ca(2+)/calmodulin-dependent protein kinases (CaMKs) are important intracellular mediators in the mediation of stimulus-secretion coupling and excitation-contraction coupling in a wide variety of cell types. We attempted to identify and characterize the functional roles of CaMK in mediating pancreatic enzyme secretion. Immunoprecipitation and immunoblotting studies using a CaMKII or CaMKIV antibody showed that rat pancreatic acini expressed both CaMKII and CaMKIV. Phosphotransferase activities of CaMKs were measured by a radioenzyme assay (REA) using autocamtide II, peptide gamma and myosin P-light chain as substrates. Although CaMKII and CaMKIV use autocamtide II as a substrate, peptide gamma is more efficiently phosphorylated by CaMKIV than by CaMKII. Intact acini were stimulated with cholecystokinin (CCK)-8, carbachol (CCh) and the high-affinity CCK-A receptor agonist, CCK-OPE, and the cell lysates were used for REA. CCK-8, CCh and CCK-OPE caused a concentration-dependent increase in CaMKs activities. When autocamtide II was used, maximal increases were 1.5-1.8-fold over basal (20.2+/-2.0 pmol/min/mg protein), with peaks occurring at 20 min after cell stimulation. In separate studies that used peptide gamma, CCK-8, CCh and CCK-OPE dose-dependently increased CaMKIV activities. Maximal increases were 1.5-2.4-fold over basal (30.7+/-3. 2 pmol/min/mg protein) with peaks occurring at 20 min after cell stimulation. Peak increases after cell stimulation induced by peptide gamma were 1.8-2.8-fold higher than those induced by autocamtide II. CCK-8, CCh and CCK-OPE also significantly increased phosphotransferase activities of myosin light chain kinase (MLCK) substrate (basal: 4.4+/-0.7 pmol/min/mg protein). However, maximal increases induced by MLCK substrate were less than 10% of those occurring in peptide gamma. Characteristics of the phosphotransferase activity were also different between autocamtide II and peptide gamma. When autocamtide II was used, elimination of medium Ca(2+) in either cell lysates or intact cells resulted in a significant decrease in the activity, whereas it had no or little effect when peptide gamma was used. This suggests that Ca(2+) influx from the extracellular space is not fully required for CaMKIV activity and Ca(2+) is not a prerequisite for phosphotransferase activity once CaMKIV is activated by either intracellular Ca(2+) release or intracellular Ca(2+) oscillations. The specific CaMKII inhibitor KN-62 (50 microM) had no effect on the CaMKIV activity and pancreatic enzyme secretion elicited by CCK-8, CCh and CCK-OPE. The specific MLCK inhibitor, ML-9 (10 microM), also did not inhibit CCK-8-stimulated pancreatic amylase secretion. In contrast, wide spectrum CaMK inhibitors, K-252a (1 microM) and KT5926 (3 microM), significantly inhibited CaMKIV activities and enzyme secretion evoked by secretagogues. Thus, CaMKIV appears to be an important intracellular mediator during stimulus-secretion coupling of rat pancreatic acinar cells.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

Growth patterns of superficially elevated neoplasia in the large intestine.

BACKGROUND: The growth pattern and malignant potential of superficially elevated neoplastic lesions remain controversial. A flat adenoma is classified as a superficially elevated neoplasm that characteristically demonstrates high-grade dysplasia despite its small size. In contrast, a nodule-aggregating (NA) tumor, which consists of multiple small aggregated nodules, can also be classified as superficially elevated neoplasia. METHODS: In this prospective study, 2720 consecutive patients undergoing total colonoscopy were examined for superficially for elevated lesions. Clinicopathologic characteristics, Ki-ras mutational status, and overexpression of p53 protein were compared in 25 NA tumors and 55 flat adenomas without a central depression (flat tumor). RESULTS: All flat tumors had a tubular pattern, whereas 21 of 25 NA tumors showed a villotubular or tubulovillous pattern. Ki-ras mutation was observed in 44% of NA tumors but in none of the flat tumors. Overexpression of p53 protein was found in 12% of NA tumors and 7% of flat tumors. CONCLUSIONS: NA tumors and flat tumors have different clinicopathologic and genetic characteristics, although both types of tumor are classified as superficially elevated lesions.

Adenocarcinoma↗

Evaluation of balloon-occluded hepatic venography with carbon dioxide for portography and correlation between retrograde portogram and liver function in patients with liver cirrhosis.

Background/Aim: Hepatic venography with a positive-contrast medium has been reported as a method for evaluating liver disease. However, the contrast medium used in this method provides insufficient portal vein observation and may cause severe liver injuries. Carbon dioxide (CO(2)), a negative-contrast medium, may be able to depict the portal vein system with minimal hepatic toxicity. The aim of this study was to evaluate the usefulness and side-effects of balloon-occluded hepatic venography with CO(2) (CO(2) venography) and to evaluate the correlation between retrograde portogram and liver function in patients with cirrhosis. Subjects and methods: The subjects consisted of 23 biopsy-proven cirrhotic patients (male:female, 16:7; age, 58+/-12 years, range 34-80). The causes of cirrhosis were alcohol intake in ten, HCV infection in ten, HBV infection in one, primary biliary cirrhosis in one and Budd-Chiari syndrome in one. Of these patients, six were complicated with hepatocellular carcinoma (HCC). CO(2) venography was performed with an occlusion balloon catheter, and 25 ml of CO(2) was infused. CO(2) portograms were scored as follows: 0, no visualization of portal veins; 1, visualization of peripheral portal branches; 2, unilateral first portal branch; 3, bilateral first portal branches; 4, main portal vein; 5, left gastric vein, superior mesenteric vein and splenic vein. Hepatic venous pressure gradient (HVPG), cardiac functions, biochemical analysis, blood gas analysis and oxygen (O(2)) saturation monitoring were measured simultaneously. Arterio-portography was also performed. To evaluate the usefulness of CO(2) venography in patients with HCC accompanied by portal vein tumor thrombus (PVTT), three patients were also examined. Results: No significant changes in ALT, AST, O(2) saturation or blood gas data were observed after CO(2) venography. A statistically significant positive correlation was observed between CO(2) portogram scores and Child-Pugh scores (r=0.68, P=0.003). The correlations between CO(2) portogram scores and HVPG, and the forms of gastroesophageal varices in patients without PVTT and major shunts were not significant. The CO(2) portogram score was significantly higher in patients with alcoholic liver cirrhosis than in those with HCV-positive cirrhosis (P=0.04). Cavernous transformation and peripheral portal branches were demonstrated in patients with HCC accompanied by PVTT. These findings could not be observed by arterio-portography. Conclusion: CO(2) venography to obtain retrograde portogram is a safe and useful method for evaluating the portal vein system and liver function in patients with liver cirrhosis.

Journal Article↗

Studies on neurosteroids. Part XIII. Characterization of catechol estrogens in rat brains using liquid chromatography-mass spectrometry-mass spectrometry.

The existence of catechol estrogens in rat brains was clarified using liquid chromatography-atmospheric pressure chemical ionization-ion trap-mass spectrometry-mass spectrometry (LC-APCI-MS2). The catechol estrogens were extracted in the presence of ascorbic acid and then derivatized to acetates with acetic anhydride and pyridine. After a successive purification with silica gel mini-column chromatography, reversed-phase solid-phase extraction and preparative HPLC, the obtained fractions containing the catechol estrogen acetates were subjected to LC-APCI-MS2. 2-Hydroxyestrone, 2-hydroxyestradiol and their 4-hydroxy isomers were identified as acetates by comparison with authentic samples based on their chromatographic behavior and mass spectral data. The derivatization to acetate was useful for the treatment of labile catechol estrogens.

Acetates↗