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Biomedical subjects

M Wakabayashi

Publications and source records attributed to M Wakabayashi.

At least 19 recordsLinked to original sources
PubMed1999

Percutaneous microwave coagulation therapy for patients with small hepatocellular carcinoma: comparison with percutaneous ethanol injection therapy.

BACKGROUND: The authors compared the efficacy of percutaneous microwave coagulation therapy (PMCT) and percutaneous ethanol injection therapy (PEIT) in the treatment of patients with cirrhosis and a solitary nodular hepatocellular carcinoma (HCC) < or = 2 cm in greatest dimension. METHODS: Of 43 patients with well-differentiated HCC, 23 were treated with PMCT and 20 with PEIT. Of the 47 patients with moderately or poorly differentiated HCC, 25 were treated with PMCT and 22 with PEIT. In a retrospective, nonrandomized study, the prognoses of 90 patients during the 12-72 months preceding the study were analyzed according to histologic tumor grade. RESULTS: The overall 5-year survival rates for patients with well-differentiated HCC treated with PMCT (70%) and PEIT (78%) were not significantly different. No difference between the patterns of recurrence was observed. Among the patients with moderately or poorly differentiated HCC, overall survival with PMCT (5-year survival rate: 78%) was significantly better than with PEIT (5-year survival rate: 35%) (P = 0.03). Nine of 22 patients with moderately or poorly differentiated HCC treated with PEIT experienced recurrence in the original target subsegment. Only 2 of 25 patients treated with PMCT had a recurrence in the same subsegment as the initial tumor. CONCLUSIONS: PMCT may be superior to PEIT for the local control of moderately or poorly differentiated small HCC.

Aged↗
PubMed1999

Percutaneous microwave coagulation therapy for solitary metastatic liver tumors from colorectal cancer: a pilot clinical study.

OBJECTIVE: Percutaneous microwave coagulation therapy (PMCT) was performed for metachronous small solitary liver tumors measuring < or = 3.0 cm in diameter that had metastasized from colorectal cancer. PMCT was used for local control of the lesions, and the efficacy of this treatment was assessed. METHODS: In 15 patients, a microwave electrode (specially designed for this purpose, 25 cm long and 2.0 mm thick) was inserted percutaneously into the tumor area under ultrasonic guidance. Microwaves at 80 watts were used to irradiate the tumor and the surrounding area. RESULTS: Thirteen of the 15 metastatic tumors were radically ablated by 3-10 applications of microwave irradiation. Although the follow-up period was short (9-37 months), 10 patients survived. No recurrence has been detected in the treated area (except two foci where PMCT was insufficient), and no serious side effects or complications were encountered during or after the PMCT. In four of the five nonsurviving patients, death was due to metastases to the bone, brain, lung, or other areas of the liver despite complete local tumor control by PMCT. CONCLUSION: PMCT is a safe and effective treatment for metachronous small liver tumors that have metastasized from colorectal cancer.

Aged↗
PubMed1999

Clinicopathologic significance of protein induced vitamin K absence or antagonist II and alpha-fetoprotein in hepatocellular carcinoma.

Protein induced vitamin K absence or antagonist II (PIVKA-II) and alpha-fetoprotein (AFP) have been considered useful serum markers of hepatocellular carcinoma (HCC). In this study, we examined the clinicopathologic significance of these tumour markers in patients with HCCs by measuring their serum levels and performing immunohistochemistry. We studied 349 Japanese patients with HCCs. Their serum PIVKA-II and AFP levels were determined by enzyme immunoassay before treatment. We examined the correlations between serum PIVKA-II and AFP levels and tumour size, presence of satellite nodules, histologic HCC grade, and concomitant liver diseases and subjected tumour tissues to immunohistochemical staining to detect PIVKA-II and AFP expression. The serum PIVKA-II levels of patients with poorly differentiated HCCs were significantly higher than those of patients with well and moderately differentiated HCCs (p<0.05) and they were higher in HCC patients with than without satellite nodules. The serum AFP levels were influenced significantly by concomitant liver diseases, but not by the other factors. Immunohistochemical staining revealed the PIVKA-II expression levels of poorly differentiated HCCs were higher than those of well and moderately differentiated HCCs (p<0.05). Some HCC cells were PIVKA-II-positive, others were AFP-positive, and some expressed both. The serum PIVKA-II concentration was a better indicator of HCC than AFP, as it was not influenced by concomitant liver diseases. The presence of PIVKA-II in serum correlated with the presence of satellite nodules and the histologic HCC grade, a result concordant with the immunohistochemical findings.

Aged↗
PubMed1998

Characterization of cytochrome P450 (CYP3A12) induction by rifampicin in dog liver.

1. Effects of rifampicin (Rif) on the contents of cytochrome P450 (P450) enzymes (CYP1A1/2, 2B11, 2C21 and 3A12) assessed by enzyme-linked immunosorbent assay and catalytic activities (ethoxyresorufin O-deethylase, and testosterone 6 beta-, 16 alpha- and 16 beta-hydroxylase; 6 beta-, 16 alpha- and 16 beta-OHT) in dog liver microsomes were compared between liver lobes of both the male and female dogs. 2. In the control dogs, the contents of individual P450 enzymes and their activities showed no significant differences between individual liver lobes and between the sexes. 3. Rif treatment (10 mg/kg/day, p.o. for 7 days) induced substantial increases in the content of CYP3A12 and 6 beta- and 16 beta-OHT activities, and slight increases in the content of CYP2B11 and 16 alpha-OHT activity, and their elevated levels were virtually the same between liver lobes. The magnitudes of the elevation of the CYP3A12 level and 6 beta- and 16 beta-OHT activities compared with control levels appeared to be greater in the female dogs. However, the ratios of their magnitudes (CYP3A content/6 beta-OHT activity and CYP3A content/16 beta-OHT activity) showed no differences between the sexes. 4. In both the control and Rif-treated dogs, the activities of 6 beta- and 16 beta-OHT were specifically inhibited by anti-CYP3A12 antiserum, and 16 alpha-OHT activity was specifically inhibited by anti-CYP2B11 and anti-CYP2C21 antiserum. 5. These results indicate that Rif treatment induces the expression of CYP3A12 protein, and correlates well with the elevation of its catalytic activity (6 beta- and 16 beta-OHT), and that the female dog is more responsive to Rif treatment as compared with the male.

Animals↗
PubMed1998

Postoperative chemotherapy may improve prognosis in unresectable gastric cancer.

We have retrospectively evaluated to prognosis of patients with unresectable gastric cancer (UGC) and the effect of postoperative chemotherapy on that prognosis. One hundred patients who died of UGC included 37 patients who received postoperative chemotherapy (chemotherapy group) and 63 patients who did not receive postoperative chemotherapy (control group). Chemotherapy regimens were as follows: intravenous mitomycin (MMC) plus 5-fluorouracil (5-FU) (n=15), oral 5-FU alone (n=10), intravenous methotrexate (MTX) plus 5-FU (n=8), intravenous cisplatin plus 5-FU (n=2), and hepatic arterial infusion of 5-FU plus oral 5-FU (n=2). No prior chemotherapy or radiation therapy was given. All patients' cancers were stage IV. Median survival of the chemotherapy group (238 days) was significantly longer than the control group (137 days). The 1-year survival rate in the treated group was 19.0% but only 2.4% in the control group (p < 0.01). Patients with palliative gastrojejunostomy did not survive significantly longer than those having laparotomy alone or ileal tube insertion. We conclude that the prognosis for patients with UGC remains very poor, but postoperative chemotherapy may contribute to prolonged survival in patients with UGC.

Adenocarcinoma↗
PubMed1998

Hepatic infarction following percutaneous ethanol injection therapy for hepatocellular carcinoma.

We report on two patients who developed hepatic infarction after undergoing percutaneous ethanol injection therapy (PEIT) for hepatocellular carcinoma (HCC). In both cases, liver function parameters deteriorated immediately after the ethanol injection, and enhanced computed tomography images showed a wedge-shaped avascular low-density area due to hepatic infarction. In one patient, PEIT was performed for a nodule treated with transcatheter arterial infusion (TAI) using a suspension of styrene maleic acid neocarzinostatin (SMANCS) 4 weeks before. In the other patient, TAI with SMANCS had been carried out 14 months previously for a different nodule in the same segment where the nodule treated with PEIT was located. When PEIT is used for patients with HCC who have previously undergone TAI, especially with SMANCS, PEIT may induce hepatic infarction.

Antineoplastic Agents↗
PubMed1998

Detection of circulating tumor cells in a patient with intravascular lymphomatosis: a case study examined by the cytology method.

Detection of circulating tumor cells in a patient with intravascular lymphomatosis (IVL) of the lung is reported. Peripheral blood cells were suspended in an isotonic sodium chloride solution, and red blood cells were lysed. The suspension was smeared on glass slides, fixed in 95% ethanol solution and stained using the Papanicolaou method. At the diagnosis of IVL, approximately 65 tumor cells were detected in one smear preparation, which contained about 8 x 10(5) nucleated cells. However, tumor cells disappeared from peripheral blood when those in the lung were eliminated by multiagent chemotherapy. Cytology examination of peripheral blood cells may be of assistance in the early diagnosis of IVL and in the assessment of therapeutic intervention.

Adult↗
PubMed1998

Cloning and characterization of the promoter region of monkey thymidylate synthase gene.

Thymidylate synthase (TS) catalyzes the conversion of deoxyuridylate to thymidylate. Promoter regions of the TS gene from three vertebrates, human, mouse and rat, have been analyzed so far. A unique inverted repeat was present in the promoter region of the human, but not in the mouse and rat, TS genes, and the feature of the promoter region is considerably different between the human TS gene and the two rodent TS genes. To examine whether the characteristics of the human TS gene promoter is intrinsic to human or primate, we cloned a DNA fragment containing the promoter region of the monkey TS gene and determined the nucleotide sequence in this region. The nucleotide sequence in the promoter region of the monkey TS gene was revealed to have 88% homology with that in the corresponding region of the human TS gene. The unique repeated structure mentioned above was also found in the monkey TS gene. Furthermore, the Sp1-binding motif and the CACCC box were found to be conserved in the monkey TS gene. The result of chloramphenicol acetyltransferase assay suggested that the Sp1-binding motif and the CACCC box are essential for the promoter activity of the monkey TS gene, as in the case of the human TS gene.

Animals↗
PubMed1998

[Renal function monitoring using an ambulatory renal monitor].

BACKGROUND AND PURPOSE: Diethylenetriamine penta acetic acid (99mTc-DTPA), a substance which indicates glomerular filtration, is distributed equally in blood and tissue after a bolus intravenously injection. Ambulatory Renal Monitor (ARM) is a portable and non invasive device which monitors extracorporeally the clearance of intravenously injected 99mTc-DTPA. We examined correlation between half-time of clearance estimated by ARM and glomerular filtration rare, and clinical usefulness of ARM for a renal function monitoring. MATERIALS AND METHODS: The purposes of this paper are to describe the results obtained through basic analysis experiments and reproducibility in normal control, and its clinical application for 9 renal transplant patients, three drug-induced renal damage, one acute renal failure, one hemolytic uremic syndrome (HUS), two chronic nephritis, one donor of renal transplantation, one ureteral tumor, three renal tumors, two ureteral stones, one bilateral hydronephrosis and two normal controls. The half time of clearance of the tracer measured by an ARM. (ARM-HTC) is compared with the half time of clearance of the tracer measured by repeated blood sampling (Sampling-HTC) as a golden standard, serum creatinine and creatinine clearance. RESULTS: A significant correlation (linear) was detected when ARM-HTC was compared with Sampling-HTC (r = 0.91), 1/serum creatinine (r = 0.85) or creatinine clearance (r = 0.82), although ARM-HTC showed a delay compared with Sampling-HTC. CONCLUSIONS: The reason of this delay may be due to a difference in half-time when the tracer distributed in the blood and tissue. The results indicate that the estimation of 99mTc-DTPA clearance by ARM is valuable for renal function evaluation in wide ranges of renal function and in different origins of renal dysfunction such as in renal transplantation.

Adult↗
PubMed1997

Neuropathology of sporadic amyotrophic lateral sclerosis of long duration.

We performed post-mortem examinations of three patients with progressive neurogenic amyotrophy of long duration. One patient had been clinically diagnosed as having sporadic amyotrophic lateral sclerosis (ALS) and two had been diagnosed with progressive spinal muscular atrophy (PSMA). The disease durations were 10, 17 and 20 years, respectively, and all of the patients died of respiratory failure with no artificial respiratory support. In all of the patients, both the upper and lower motor neuron systems were affected; degeneration of the former was definite, but was milder than that usually encountered in sporadic ALS patients, and the histopathology of the latter was identical to that of sporadic ALS. Light microscopy revealed Bunina bodies, which are characteristic of sporadic ALS, in the remaining anterior horn cells of each patient. In addition, ubiquitin-positive skein-like inclusions were also identified, immunohistochemically, in the remaining anterior horn cells of each patient. Neuron counts indicated that the number of neurons was preserved in Clarke's column in these patients, but was significantly reduced in the intermediolateral nucleus, compared with control subjects. Based on these findings, we think that these three patients, with long disease durations, were affected by essentially the same underlying disease process as that of sporadic, classical ALS. Moreover, we question the neuropathological occurrence of sporadic ALS without involvement of the upper motor neuron system, namely, pure PSMA or lower motor neuron disease.

Aged↗
PubMed1997

Hemorrhage into a simple liver cyst: diagnostic implications of a recent case.

Hemorrhage complicating simple liver cyst is rare. On imaging studies, the differential diagnosis between intracystic hemorrhage and cystadenocarcinoma of the liver is unreliable, and hepatectomy has been performed for benign liver cyst in this situation. We describe the characteristics of hemorrhage into a liver cyst in a patient who underwent dome resection of the cyst. In our patient, important diagnostic findings included benign cytologic features in a cyst fluid specimen aspirated with ultrasonographic guidance and a fall in hemoglobin and hematocrit, suggestive of hemorrhage. Other informative features were absence of communication between the intrahepatic bile ducts and the cystic liver lesion upon endoscopic retrograde cholangiopancreatography, as well as benign intraoperative frozen-section histology.

Aged↗
PubMed1997

Endoscopic nasobiliary drainage for bile duct injury after laparoscopic cholecystectomy.

Bile duct injuries are a potential complication of laparoscopic cholecystectomy (LC). A patient who underwent successful endoscopic nasobiliary drainage (ENBD) for a bile duct injury sustained during LC is presented. Of particular note, the patient also had Chilaiditi's syndrome. A 59-year-old woman was admitted with symptomatic cholecystolithiasis and Chilaiditi's syndrome. LC was performed. Postoperatively, the patient complained of abdominal discomfort. Laboratory examination revealed cholestasis. Bilious material began spilling from an intraabdominal drain. Subsequent endoscopic retrograde cholangiopancreatography (ERCP) showed bile leakage. ENBD was performed. Repeat ERCP 10 days later failed to show a bile leak or stenosis of the common bile duct. The patient improved rapidly and had no complaints after the procedure. ENBD is a useful endoscopic technique to prevent peritonitis from bile leakage after LC. Chilaiditi's syndrome is not a contraindication for LC.

Bile Ducts↗
PubMed1997

Clinicopathologic features of submucosal carcinoma of the stomach.

A retrospective study of 155 patients with submucosal gastric carcinoma compared the clinicopathologic features with mucosal and muscularis proprial gastric carcinoma. Fifty-seven percent of the patients presented with gastrointestinal symptoms, whereas 36.1% had been detected by mass screening. The incidence of curative resection, lymph node metastasis, and complications were 96.1, 20.6, and 14.8%, respectively. Two patients died of sepsis and pulmonary infarction 30 days post-operatively. Five patients died of recurrent gastric cancer 1-5 years postresection. The overall 5-year survival rate was 90.2%. Recurrence patterns, histologic type, lymph node metastasis, lymphatic and venous infiltration, and growth pattern were similar to those of muscularis proprial carcinoma rather than mucosal carcinoma. Therefore, curative gastrectomy with extended lymphadenectomy (D2) may be feasible for submucosal carcinoma of the stomach.

Adenocarcinoma↗
PubMed1997

[Diagnostic imaging of renal pedicle injury].

We reviewed the radiological findings of 8 patients with renal pedicle injury admitted to our emergency center from January 1986 through September 1995 and compared them with the previously reported findings. The patients included 3 with renal artery occlusion and 5 with avulsion or disruption of renal pedicle vasculature. Extended retroperitoneal hematoma such as contralateral pararenal or central parahilar hematoma was visualized in all 5 cases with avulsion or disruption of renal pedicle vasculature. Although lack of contrast enhancement of injured renal parenchyma is a hall-mark of renal pedicle injury, three cases did not demonstrate this typical finding. In these three cases, one showed partial and the others showed total enhancement of the injured renal parenchyma on contrast enhanced CT. Partial enhancement in one case was found to represent total occlusion of the main renal artery and an intact accessory polar branch on angiography. The other two cases showed total enhancement of the renal parenchyma, with renal vein perforation done and complete disruption of the main renal artery and vein in the other. The latter findings were thought to be due to the maintenance of vascular flow surrounded by hematoma. In conclusion, when central parahilar hematoma is identified, the possibility of renal pedicle injury should be considered even if the renal parenchyma is well enhanced.

Adolescent↗
PubMed1996

Control of thymidine kinase during liver regeneration after partial hepatectomy.

To elucidate the molecular basis for the periodic change of thymidine kinase (TK) activity, the expressions of TK protein and TK mRNA were examined during liver regeneration. TK protein level, quantified by immunoblotting assay using the polyclonal antiserum against rat TK polypeptide produced in Escherichia coli, increased 13-fold compared with the normal at 24 h after partial hepatectomy. This was closely correlated with a 11-fold increase in TK activity. Northern blot analysis showed that the partial hepatectomy caused 12- and 8-fold increase in 2.6 kb and 1.1 kb TK mRNA at 24 h after surgery, respectively. During next 12 h the levels of both TK mRNA species reduced to 5-fold of the normal base level. This reduction was coupled with a similar decrease in the activity as well as in the amount of TK protein. The TK mRNA levels were strictly proportional to the levels of TK activity and TK protein at 48 h and 72 h after partial hepatectomy. These results demonstrate that the change in TK activity is controlled at the mRNA level during liver regeneration. The injection of alpha-adrenoceptor antagonist, phenoxybenzamine, calcium channel blocker, nifedipine or calmodulin inhibitor, trifluoperazine was also found to inhibit TK activity by the repression of its mRNA level.

Adrenergic alpha-Antagonists↗
PubMed1996

Identification of drug-resistant myeloid leukemic cells by measurement of DNA content, nuclear area, and detection of P-glycoprotein.

BACKGROUND: This study was designed to evaluate the significance of aneuploidy in DNA ploidy, nuclear area, and expression of P-glycoprotein (P-GP) in differentiating drug-resistant myeloid leukemic cells (DRMLC) from drug-sensitive myeloid leukemic cells. METHODS: Bone marrow aspirates from 28 myeloid leukemic patients were fixed in 95% ethanol solution and stained using the Papanicolaou method. The nuclear area and DNA content were measured. An immunohistochemical study was performed using monoclonal antibody (JSB-1) directed against P-GP. RESULTS: Leukemic cell morphology changed once or twice after the diagnosis of acute myeloid leukemia (AML), blastic crisis (BC) of chronic myeloid leukemia, or chronic neutrophilic leukemia. DRMLC showed severe atypia and were morphologically distinguishable from normal myeloblasts, promyelocytes, and drug-sensitive leukemic cells at the diagnosis of AML or BC. The mean nuclear index (NI) and DNA index (DI) of DRMLC were significantly larger than those of drug-sensitive leukemic cells of AML or BC. The frequency of aneuploidy and P-GP expression was 9.1% and 4.5%, respectively, at the diagnosis of AML or BC, and 92.8% and 28.5%, respectively, for resistant disease. The incidence of heterogeneity in DNA ploidy was 86.3%. CONCLUSIONS: DI and NI values larger than 1.2 and the expression of P-GP are significant indications of DRMLC.

ATP Binding Cassette Transporter, Subfamily B, Mem↗