Biomedical subjects

T Morisaki

Publications and source records attributed to T Morisaki.

At least 55 records · Page 3Linked to original sources

PubMed2000

Laparoscopically assisted distal gastrectomy for early gastric cancer: is it superior to open surgery?

BACKGROUND: The purpose of this study was to compare clinical outcomes between laparoscopically assisted and open distal gastrectomy for early gastric cancer. METHODS: The records of 21 patients who underwent laparoscopically assisted distal gastrectomy (LG) for preoperative diagnosis of intramucosal gastric carcinoma between January 1996 and August 1998 were reviewed and compared with those of 31 open distal gastrectomy patients during the same period. RESULTS: Age, gender, and size and histologic differentiation of the lesions were matched. Those located at the body of the stomach (p = 0.011) and those macroscopically depressed (p = 0.049) were subjected more frequently to open surgery. Laparoscopically assisted gastrectomy required significantly longer operative time (p < 0.001) with less extensive lymph node dissection (p < 0.001). However, time to start of walking (p = 0.032), time to flatus (p = 0.002), duration of postoperative fever (p = 0.027), and postoperative hospital stay (p = 0.001) were significantly shorter in the LG group, and this group had a lower white blood cell count on the first postoperative day (p = 0.010). Blood loss and time to oral intake were comparable between the groups. Complications included one conversion to open surgery, one leakage, and one stenosis in the LG group, and two leakages and an atelectasis in the OG group. CONCLUSIONS: Although LG requires longer surgical time, this retrospective study suggests that it is superior to open surgery in terms of faster postoperative recoveries, shorter hospital stays, and cosmetic outcomes.

Adenocarcinoma↗

PubMed2000

Block of sodium channels by divalent mercury: role of specific cysteinyl residues in the P-loop region.

Divalent mercury (Hg(2+)) blocked human skeletal Na(+) channels (hSkM1) in a stable dose-dependent manner (K(d) = 0.96 microM) in the absence of reducing agent. Dithiothreitol (DTT) significantly prevented Hg(2+) block of hSkM1, and Hg(2+) block was also readily reversed by DTT. Both thimerosal and 2,2'-dithiodipyridine had little effect on hSkM1; however, pretreatment with thimerosal attenuated Hg(2+) block of hSkM1. Y401C+E758C rat skeletal muscle Na(+) channels (mu1) that form a disulfide bond spontaneously between two cysteines at the 401 and 758 positions showed a significantly lower sensitivity to Hg(2+) (K(d) = 18 microM). However, Y401C+E758C mu1 after reduction with DTT had a significantly higher sensitivity to Hg(2+) (K(d) = 0.36 microM) than wild-type hSkM1. Mutants C753Amu1 (K(d) = 8.47 microM) or C1521A mu1 (K(d) = 8.63 microM) exhibited significantly lower sensitivity to Hg(2+) than did wild-type hSkM1, suggesting that these two conserved cysteinyl residues of the P-loop region may play an important role in the Hg(2+) block of the hSkM1 isoform. The heart Na(+) channel (hH1) was significantly more sensitive to low-dose Hg(2+) (K(d) = 0.43 microM) than was hSkM1. The C373Y hH1 mutant exhibited higher resistance (K(d) = 1.12 microM) to Hg(2+) than did wild-type hH1. In summary, Hg(2+) probably inhibits the muscle Na(+) channels at more than one cysteinyl residue in the Na(+) channel P-loop region. Hg(2+) exhibits a lower K(d) value (<1. 23 microM) for inhibition by forming a sulfur-Hg-sulfur bridge, as compared to reaction at a single cysteinyl residue with a higher K(d) value (>8.47 microM) by forming sulfur-Hg(+) covalently. The heart Na(+) channel isoform with more than two cysteinyl residues in the P-loop region exhibits an extremely high sensitivity (K(d) < 0. 43 microM) to Hg(+), accounting for heart-specific high sensitivity to the divalent mercury.

2,2'-Dipyridyl↗

PubMed2000

Myoadenylate deaminase deficiency with progressive muscle weakness and atrophy caused by new missense mutations in AMPD1 gene: case report in a Japanese patient.

A 46-year-old woman with exertional myalgia developed slowly progressive weakness in her lower extremities. She had slight muscle weakness in her facial and upper extremities, and severe muscle weakness and atrophy in lower extremities more marked in the proximal portions. Serum creatine kinase was slightly elevated. After ischemic forearm exercise test, blood ammonia had no elevation although lactate level increased normally. The computed tomography revealed that a characteristic distribution of skeletal muscle involvement with proximal and flexor muscles more severely affected than distal and extensor in the lower extremities. In addition, the left sternocleidomastoid muscle showed marked atrophy with an asymptomatic weakness of over 20 years duration suggesting abnormal development. Needle EMG examination showed a large number of easily recruited, short-duration, low-amplitude motor unit potentials in all extremities. Muscle biopsy showed absence of adenosine monophosphate deaminase activity with normal cytochrome c oxidase and phosphorylase activity. With the muscle enzyme activity assay, adenosine monophosphate deaminase activity was found to be lower than 0.2% of the controls. The DNA analysis revealed that she was compound heterozygote involving two missense mutations (R388W and R425H) in exon 9 and exon 10 of AMPD1 gene. This is the first report of primary myoadenylate deaminase deficiency with progressive weakness and atrophy caused by novel compound heterozygous mutations of AMPD1 gene, and suggests that adenosine monophosphate deaminase is closely related not only to energy metabolism but also to the development of skeletal muscle.

AMP Deaminase↗

PubMed2000

Administration of bacterial lipopolysaccharide to rats induces heme oxygenase-1 and formation of antioxidant bilirubin in the intestinal mucosa.

Heme oxygenase (HO)-1, the rate-limiting enzyme in heme degradation, is induced by oxidative stress and its major end product, bilirubin, is a potent physiological antioxidant. We studied the induction of HO-1 and bilirubin production in intestinal mucosa using a rat model of sepsis. E. coli lipopolysaccharide was administered intraperitonealy to male Wistar rats and intestinal mucosa was harvested. Intestinal lipid peroxides increased significantly at 1 hr and peaked at 170% of the control value at 5 hr. GSH significantly decreased at 3 hr, reaching the nadir of 50% of the control value at 5 hr. HO-1 mRNA was maximally induced fivefold at 3 hr and HO-1 protein maximally increased to 10 times the control value at 7.5 hr. Both bilirubin and bilirubin oxidative metabolites were maximally increased at 10 hr, to 4.3 and 3.7 times the control value, respectively. These data suggest that oxidative stress in sepsis quickly induces HO-1 in intestinal mucosa and that subsequent production of bilirubin works as an antioxidant. The small intestinal mucosa is an active participant in the general response to sepsis.

Animals↗

PubMed2000

Protein-bound polysaccharide PSK inhibits tumor invasiveness by down-regulation of TGF-beta1 and MMPs.

Transforming growth factor beta1 (TGF-beta1) and matrix metalloproteinases (MMPs) produced by tumor cells play important roles in tumor invasion. PSK, a protein-bound polysaccharide, is widely used in Japan as an immunopotentiating biological response modifier for cancer patients. In this study, we focused on the effects of PSK on invasiveness, TGF-beta1 production, and MMPs expression in two human tumor cell lines, pancreatic cancer cell line (NOR-P1) and gastric cancer cell line (MK-1P3). PSK significantly decreased the invasiveness of both cell lines through Matrigel-coated filters but did not affect cell viability, proliferation, or adhesion. Decreased invasion was associated with the inhibition of TGF-beta1, MMP-2, and MMP-9 at both mRNA and protein levels as assessed by reverse transcriptase-polymerase chain reaction, gelatin zymography, and enzyme-linked immunosorbent assay. Antibody against TGF-beta1 neutralized the MMP activities of both cell lines. PSK also suppressed the expression of urokinase plasminogen activator (uPA) and uPA receptor but did not change plasminogen activator inhibitor-1 (PAI-1) expression. Western blot analysis showed that PSK reduced uPA protein expression but not PAI-1 expression in the both cell lines. These results indicate that PSK suppresses tumor cell invasiveness through down-regulation of several invasion-related factors including TGF-beta1, uPA, MMP-2, and MMP-9.

Adjuvants, Immunologic↗

PubMed2000

[Seven patients with stage IVb advanced gastric cancer who were treated with preoperative chemotherapy].

We examined the usefulness of preoperative chemotherapy using 5-FU and low-dose CDDP in patients with stage IVb gastric cancer. Between 1996 and 1998, seven patients with stage IVb gastric cancer who received preoperative chemotherapy achieved complete or partial response. One course of the chemotherapy was as follows: arterial or venous infusion of 5-FU (500 or 250 mg/day on day 1-5) and low-dose CDDP (5-10 mg/day on day 1-5) for three weeks. In addition to preoperative chemotherapy, biological response modifiers such as OK-432 and lentinan were used. We evaluated the response with abdominal or chest CT and tumor markers. Although preoperative chemotherapy did not improve the survival rate significantly, the prognosis of these patients seemed to be relatively good. Only slight side effects were found. These results suggest that preoperative chemotherapy using 5-FU and low-dose CDDP may be useful for patients with stage IVb gastric cancer.

Aged↗

PubMed1999

A human homolog of Drosophila warts tumor suppressor, h-warts, localized to mitotic apparatus and specifically phosphorylated during mitosis.

We identified a human homolog of Drosophila warts tumor suppressor gene, termed h-warts, which was mapped at chromosome 6q24-25.1. The h-warts protein has a serine/threonine kinase domain and is localized to centrosomes in interphase cells. However, it becomes localized to the mitotic apparatus, including spindle pole bodies, mitotic spindle, and midbody, in a highly dynamic manner during mitosis. Furthermore, h-warts is specifically phosphorylated in cells at mitotic phase, most likely by Cdc2 kinase. These findings suggest that h-warts functions as a component of the mitotic apparatus and is involved in proper progression of mitosis.

Amino Acid Sequence↗

PubMed1999

Predominant germ-line mutation of the hMSH2 gene in Japanese hereditary non-polyposis colorectal cancer kindreds.

By means of PCR-SSCP and direct sequencing, we detected 12 germ-line mutations of hMSH2 or hMLH1 in 37 Japanese hereditary non-polyposis colorectal cancer (HNPCC) kindreds, of whom 15 satisfied the Amsterdam and 22 the Japanese criteria. The germ-line mutation detection rate of hMSH2 was much higher than that of hMLH1 (11/37 vs. 1/37). The total mutation detection rate of hMSH2 and hMLH1 in the Amsterdam criteria group was significantly higher than that in the Japanese criteria group (9/15 vs. 3/22). Furthermore, the mean age of the HNPCC patients in the mutation-positive group was lower than that in the mutation-negative one; the rates of both vertical transmission and multiplicity of tumors in the mutation-positive group were higher than those in the mutation-negative one. In addition, the number of patients with microsatellite instability-positive cancers in the mutation-positive group was higher than that in the mutation-negative one. Our results suggest firstly that the hMSH2 gene plays a much more important role than hMLH1 in the carcinogenesis of Japanese HNPCC patients, secondly that the rate of hMSH2 and hMLH1 mutations is high in the kindreds satisfying the Amsterdam criteria and thirdly that both the clinical phenotypes (early onset, vertical transmission and multiplicity of tumors) and the microsatellite instability status are important for the genetic screening of HNPCC.

Colorectal Neoplasms, Hereditary Nonpolyposis↗

PubMed1999

An early gastric carcinoma treatment strategy based on analysis of lymph node metastasis.

BACKGROUND: Newly developed therapies for early gastric carcinoma attempt to consider patients' quality of life, but the applicability and effectiveness of these treatments remain undetermined. METHODS: Clinicopathologic data of 612 consecutive patients with early gastric carcinoma, all of whom were treated by D1 and D2 gastrectomy, were analyzed. Patients with and without lymph node metastases were compared in relation to age and gender distributions, surgical procedures, histopathology of the tumors, 5-year prognosis, and in reference to the preoperative and intraoperative assessments. RESULTS: The overall incidence of lymph node metastases was 5.7%. Tumor depth and size were related to lymph node metastases judged by univariate and multivariate analyses. Patients with mucosal tumors showed no relation between metastatic rate and tumor size, whereas those with submucosal tumors showed an increasing metastatic rate with tumor size. In all cases but one, lymph node metastases were confined to lymph node stations defined as Group 1 locations. Preoperative endoscopic ultrasonography showed a 55% diagnostic accuracy in determining tumor depth and a 15% sensitivity in diagnosing lymph node metastases. CONCLUSIONS: Patients with early gastric carcinoma may be candidates for endoscopic mucosal resection if their tumor is confined to the mucosa and measures < 1 cm in greatest dimension. Other limited resections including D1 gastrectomy or standard D2 gastrectomy based on tumor depth and size are appropriate. Based on the current study findings, the authors propose a useful algorithm for managing such patients.

Age Factors↗

PubMed1999

Nitric oxide synthase expression and nitric oxide production in human colon carcinoma tissue.

BACKGROUND AND OBJECTIVES: Nitric oxide (NO), the production of which is dependent on NO synthase (NOS), has been shown to contribute to various pathogeneses in cancer. The aim of this study was to determine whether inducible NO synthase (iNOS) is overexpressed in human colon carcinoma tissue, and whether NO is produced in tumor tissue. METHODS: We investigated iNOS mRNA expression in 24 human colon carcinoma tissue specimens by reverse transcription-polymerase chain reaction (RT-PCR). We then examined the expression of iNOS protein and nitrotyrosine, which indicates NO production in tissue, by immunohistochemistry. The possible immunosuppressive role of NO produced by colon carcinoma cells was analyzed in vitro. RESULTS: Semiquantitative RT-PCR analysis showed that iNOS mRNA expression in carcinoma tissues is elevated significantly compared to that in noncarcinoma tissue. Immunohistochemistry revealed that iNOS and nitrotyrosine are expressed strongly in carcinoma tissues. In vitro experiments showed that the supernatant from a culture of cytokine-treated colon carcinoma cells, which contained high levels of NO, significantly reduced the phytohemagglutinin (PHA)-stimulated, human lymphocyte proliferative response (60% of the control value). CONCLUSIONS: In human colon carcinoma tissue, iNOS mRNA, protein, and NO products are overexpressed and may contribute to tumor-related immunosuppression.

Adenocarcinoma↗

PubMed1999

New therapeutic strategy for gastric carcinoma: a two-step evaluation of malignant potential from its molecular biologic and pathologic characteristics.

BACKGROUND AND OBJECTIVES: A previous study of ours indicated that platelet-derived growth factor-A (PDGF-A) mRNA expression in biopsy specimens can identify a subgroup of high-risk gastric carcinoma patients, while clinicopathologic studies have shown that lymph node involvement is an important risk factor for predicting overall survival. To identify gastric carcinoma patients at high risk for recurrence, we assessed a two-step evaluation consisting of mRNA expression of tumor growth-related factors and the histopathologic findings. METHODS: The reverse transcriptase-polymerase chain reaction (RT-PCR) was used to assay the gene expression of PDGF-A and transforming growth factor-beta1 (TGF-beta1) in 69 gastric carcinoma endoscopic biopsy specimens (prospective cohort). The corresponding gastric carcinoma surgical specimens were classified histologically. Finally, the patients' survival curves were calculated. The relationships among the mRNA expression, histopathologic findings, and survival period were analyzed statistically. RESULTS: Nodal involvement correlated with PDGF-A and TGF-beta1 mRNA expression in early and advanced carcinomas, respectively. Both PDGF-A mRNA and TGF-beta1 mRNA expression were independent preoperative prognostic indicators in advanced cases. The ratio of involved nodes (n1) to total perigastric lymph nodes dissected (percentage of involved nodes) was the most independent postoperative prognostic indicator in advanced cases. Early carcinomas were divided preoperatively into two types. Advanced carcinomas were divided preoperatively into three. These were divided again postoperatively according to the percentage of involved nodes into high- and low-malignacy groups. CONCLUSIONS: A two-step evaluation of the malignant potential of gastric carcinoma by a combination of preoperative evaluation for PDGF-A and TGF-beta1 expression and postoperative pathologic examination would yield a more accurate prognosis for patients with gastric carcinoma.

Humans↗

PubMed1999

Functional analysis of the p57KIP2 gene mutation in Beckwith-Wiedemann syndrome.

p57KIP2 is a potent tight-binding inhibitor of several G1 cyclin/cyclin-dependent kinase (Cdk) complexes, and is a negative regulator of cell proliferation. The gene encoding p57KIP2 is located at 11p15.5, a region implicated in both sporadic cancers and Beckwith-Wiedemann syndrome (BWS). Previously we demonstrated that p57KIP2 is imprinted and only the maternal allele is expressed in both mice and humans. We also showed mutations found in p57KIP2 in patients with BWS that were transmitted from the patients' carrier mothers, indicating that the expressed maternal allele was mutant and that the repressed paternal allele was normal. In the study reported here, we performed functional analysis of the two mutated p57KIP2 genes. We showed that the nonsense mutation found in the Cdk inhibitory domain in a BWS patient rendered the protein inactive with consequent complete loss of its role as a cell cycle inhibitor and of its nuclear localization. We also showed that the mutation in the QT domain, although completely retaining its cell cycle regulatory activity, lacked nuclear localization and was thus prevented from performing its role as an active cell cycle inhibitor. Consequently, no active p57KIP2 would have existed, which might have caused the disorders in BWS patients.

Animals↗

PubMed1999

The role of percutaneous transhepatic abscess drainage for liver abscess.

To evaluate the efficacy of percutaneous transhepatic abscess drainage (PTAD) as an initial choice of treatment for liver abscess, the medical records of 28 patients with liver abscess were retrospectively analyzed. The patients were predominantly men (23 of 28) with a mean age of 59 years (range, 19-86 years). Their chief complaints were fever (86%), right hypochondralgia (32%), and jaundice (11%). Fifteen of the 28 patients (54%) had hepatobiliary and pancreatic carcinoma, and 31% had postoperative liver abscess. PTAD was performed in 23 patients and surgical drainage in 5. The overall success rate for PTAD was 83%. The success rate for PTAD for patients with multiple abscesses was 83% (5 of 6), compared with a success rate of 82% (14 of 17) for patients with solitary abscess. The prognostic factors for survival were cancer and sepsis and the mortality rate for patients with cancer was 40% (6 of 15) while the mortality rate for patients with sepsis was 56% (5 of 9). As a complication of drainage, 1 patient (4%) in the PTAD group had pleural abscess due to the transpleural puncture. Our findings support the use of PTAD as the primary treatment for liver abscess, as it is safe and effective irrespective of the number of abscesses and the patient's condition.

Adult↗

PubMed1999

Comparison of treatments for hepatolithiasis: hepatic resection versus cholangioscopic lithotomy.

BACKGROUND: Hepatic resection and percutaneous transhepatic cholangioscopic lithotomy (PTCSL) are the two main approaches to the treatment of hepatolithiasis, but comparisons of longterm followup results have not been adequately reported. STUDY DESIGN: Of 86 patients with hepatolithiasis admitted to our institution between 1980 and 1996, we reviewed 54 patients: 26 who underwent hepatic resection and 28 who underwent PTCSL. Five patients who underwent postoperative cholangioscopic lithotomy were included in the former group. The remainder of the hepatolithiasis patients were not treated by hepatic resection or PTCSL and, therefore, were excluded from this study. Hepatic resections were mainly indicated for left-sided localized intrahepatic calculi, atrophic liver, and possible presence of cholangiocellular carcinoma. PTCSL was performed for right-sided, bilateral or recurrent stones at an average of 6 treatments (range 1 to 20 treatments) for each patient. There were no differences between the two groups in terms of gender or age. The recurrence rate of stones and longterm prognosis were analyzed using the Kaplan-Meier method, and other clinical factors listed below were statistically compared. RESULTS: The rate of complete removal of stones was similarly high in each group (96.2% in the hepatic resection group versus 96.4% in the PTCSL group). The complication (38.5% versus 21.4%) and 5-year survival (85.6% versus 100%) rates were comparable. Remaining bile duct stricture (18.2% versus 60.9%, p < 0.01) and 5-year recurrence rates (5.6% versus 31.5%, p < 0.05) were statistically lower in the hepatic resection group than in the PTCSL group. CONCLUSIONS: Hepatic resection, when combined with postoperative cholangioscopic lithotomy, is a preferable treatment for left-sided stones with strictures and bilateral stones.

Adult↗

PubMed1999

Hepatocyte growth factor and invasion-stimulatory activity are induced in pleural fluid by surgery in lung cancer patients.

Hepatocyte growth factor (HGF) is a stromal cell-derived cytokine that can stimulate matrix invasion by carcinoma cells. We analysed the concentrations of HGF and invasion-stimulatory activity in pleural fluid after lung surgery. The concentration of HGF in pleural fluids was measured by enzyme-linked immunosorbent assay in seven patients who underwent pulmonary resection for primary or metastatic lung cancer. The effect of the pleural fluid on cancer cell invasion across reconstituted basement membrane (Matrigel) was assessed with a Boyden chamber assay using a lung adenocarcinoma cell line, A549. HGF levels in the pleural fluid after lung surgery ranged from 6.0 to 23.0 ng ml(-1) (average: 10.2 +/- 4.3 ng ml(-1)). The matrix invasion of lung carcinoma cells in the presence of the pleural fluid was significantly higher than that in the presence of culture medium alone or sera from normal subjects (P < 0.01). The invasion-stimulatory activity of the pleural fluid was strongly inhibited by HGF-neutralizing antibody. Positive correlation was found between the HGF level and invasion-stimulatory activity in the pleural fluids and normal sera (P = 0.0073). This is the first report demonstrating that the lung surgery induces a considerable amount of HGF, which is closely correlated with the invasion-stimulatory activity of the pleural fluid.

Aged↗

PubMed1999

Intraductal papillary neoplasm of the pancreas: a clinical review of 13 benign and four malignant tumours.

OBJECTIVE: To assess of the grade of malignancy of intraductal papillary neoplasm of the pancreas (IPNP). DESIGN: Retrospective analysis. SETTING: University hospital, Japan. PATIENTS: 8 men and 9 women, mean age 67 years, with IPNP. RESULTS: 12 lesions were in the head of the pancreas, two in the body and three in the tail. There were no differences in the age and sex of the patients, the presence of diabetes mellitus or history of pancreatitis, serum concentrations of carcinoembryonic antigen, and CA 19-9, pancreatic function test, and the site of origin of benign and malignant IPNP. The mean diameter of the main pancreatic duct was 16 mm in the four malignant tumours, but 6 mm in the 13 benign IPNP (p < 0.05). 10 of the 13 benign IPNP were located in the branch duct, two in the main pancreatic duct, and another in both the main and branch ducts, while all four malignant IPNP were situated in the main duct (p < 0.01). Mural nodules were detectable preoperatively in all four malignant IPNP but in only 5 of the 13 benign tumours (39%). The mean diameter of the mural nodules in the five benign IPNPs was 3 mm, whereas that in the four malignant ones was 24 mm (p < 0.01). All but one patient (who had a malignant IPNP) were alive for one to 36 months (mean 16 months) after resection. CONCLUSIONS: IPNP is a unique variant of pancreatic exocrine neoplasm with a good prognosis after resection. The diameter of the main pancreatic duct, size of the mural nodule, and site of the tumour (main pancreatic duct or branch duct) differ significantly between benign and malignant tumours.

Adenocarcinoma, Papillary↗

PubMed1999

Phospholipase A2 mediates nitric oxide production by alveolar macrophages and acute lung injury in pancreatitis.

OBJECTIVE: Reportedly, nitric oxide (NO) derived from alveolar macrophages (AMs) and increased serum phospholipase A2 (PLA2) activity are associated with the pathogenesis of lung injury in acute pancreatitis. The authors examined the possibility that PLA2 causes, in part, the induction of NO production by AMs in pancreatitis. METHODS: Pancreatitis was induced in rats by selective pancreatic duct ligation (SPL). AMs were stimulated with PLA2 or SPL rat serum, with or without administration of the PLA2 inhibitor quinacrine. Then NO production from the AMs was measured by the Griess method, inducible NO synthase mRNA expression of AMs was analyzed by the reverse transcription-polymerase chain reaction, and cytotoxic effects of AMs on human umbilical vein endothelial cells was examined by a 51Cr release assay. In vivo, the effect of quinacrine on lung injury was determined by measuring the arterial blood oxygen pressure (PaO2), lung weight, and lung permeability using Evans blue dye concentration of SPL rat. RESULTS: In vitro, the serum with high PLA2 activity induced NO production by rat AMs. PLA2 (50 ng/ml) induced significant amounts of NO production, inducible NO synthase mRNA expression, and cytotoxicity toward the human umbilical vein endothelial cells in normal rat AMs, and these activities were significantly inhibited by quinacrine. In vivo, rats with pancreatitis that were given quinacrine showed decreased concentrations of NO2- and NO3- in the bronchoalveolar lavage fluid, and the PaO2, lung edema, and lung permeability were improved significantly. CONCLUSION: PLA2 induces AMs to release NO, which contributes to lung injury in acute pancreatitis. This lung injury was prevented by the administration of the PLA2 inhibitor quinacrine.

Acute Disease↗

PubMed1999

Evaluation of induction of CYP3A mRNA using the HepG2 cell line and reverse transcription-PCR.

Cytochrome P-450 3A (CYP3A) is a drug-metabolizing enzyme dominant in the human liver. We have designed a useful method for evaluation of induction of CYP3A mRNA by various drugs using HepG2 cells known to retain liver-cellular functions. Using semi-quantitative reverse transcription-PCR (RT-PCR), we demonstrated that cultured HepG2 cells constitutively expressed CYP3A mRNA. This mRNA was expressed at high levels in culture for several days and was further induced by several drugs (e.g. rifampicin (RFP), dexamethasone). Treatment of HepG2 cells with RFP induced CYP3A mRNA in a dose- and time-dependent manner. Cells in culture for 48 h with 1 and 50 micromol/l RFP increased 2.7- and 5.0-fold in CYP3A mRNA expression in comparison with untreated controls, respectively. In contrast, no change in the amount of CYP3A mRNA was observed when the cells were treated with cimetidine which has been shown to inhibit CYP3A activity. Our method using a combination of HepG2 cells and RT-PCR allowed evaluation of the degree of induction of CYP3A mRNA both easily and rapidly.

Aryl Hydrocarbon Hydroxylases↗