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M Wakabayashi

Publications and source records attributed to M Wakabayashi.

At least 55 records · Page 3Linked to original sources
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↗
PubMed1995

Lewis Y antigen expression in hepatocellular carcinoma. An immunohistochemical study.

BACKGROUND: The altered expression of the Lewis blood group-related antigens during malignant transformation can be used clinically as a tumor marker or as a prognostic indicator. The Lewis Y (LeY) antigen, which is one of the Type 2 human blood group-related antigens, also is thought to behave as an oncodevelopmental cancer-associated antigen. In this study, the authors examined the association between human LeY antigen expression and the clinicopathologic features of HCC, including its proliferative activity. METHODS: Forty-six histologically confirmed cases of HCC were studied retrospectively. Liver biopsy specimens from the main tumor of each case were obtained under ultrasonic guidance before treatment was initiated. The formalin fixed, paraffin embedded serial sections were immunostained using a modification of the avidin-biotin-peroxidase complex method, with a primary monoclonal antibody (MoAb) directed against the LeY antigen (BM-1/JIMRO). The relationship between LeY antigen expression and the HCC's proliferative activity was analyzed similarly by immunohistochemical methods using a primary MoAb directed against the Ki-67 antigen (MIB 1). In addition, to clarify the relationship between LeY antigen expression and the histologic heterogeneity within HCC, seven cases of surgically resected HCC also were immunostained. RESULTS: The LeY antigen was detected on the membrane and in the cytoplasm of the cancer cells. Of the 46 HCC cases, 20 (43.5%) expressed the LeY antigen in the tumor cells. There was no correlation between LeY antigen expression and the maximum tumor dimension or the Stage. However, the incidence of LeY antigen-positive cases in poorly differentiated HCCs was found to be significantly higher than that in well or moderately differentiated HCCs (P < 0.01). In resected HCC cases, LeY antigen expression within HCC nodules was frequently greater in the less differentiated tumor than in adjacent differentiated tumor. Moreover, the incidence of LeY antigen expression in alpha-fetoprotein (AFP)-positive (AFP > or = 200 ng/ml) HCC cases was significantly higher than that in AFP-negative (AFP < 200 ng/ml) HCC cases (P < 0.05). Furthermore, the mean value of the Ki-67 labeling index in LeY antigen-positive HCC cases (25.2 +/- 11.3%) was significantly higher than that in LeY antigen-negative HCC cases (9.4 +/- 4.1%) (P < 0.001). CONCLUSIONS: These results suggest that LeY antigen expression correlated closely to the dedifferentiation and proliferative activity of HCC.

Antibodies, Monoclonal↗
PubMed1995

Chronic cholecystitis following hemobilia due to traumatic intrahepatic injury.

We report a patient who presented with colicky abdominal pain, hematemesis, and melena following a blunt abdominal injury sustained in an automobile accident. Serologic tests suggested liver dysfunction and computed tomography (CT) revealed dilatation of the intrahepatic bile duct. Duodenoscopy demonstrated hemobilia originating from the duodenal papilla of Vater. Angiography revealed a pseudoaneurysm of the hepatic artery and angiographic embolization sucessfully stopped the hemorrhaging. However, even following the angiographic embolization, the patient remained symptomatic and repeat CT demonstrated thickening of the gallbladder wall and a lesion resembling a blood clot. We strongly suspected cholecystitis and performed a laparoscopic cholecystectomy. Grossly, the resected specimen revealed wall thickening with a congested mucosa and three blood clots; histologically, these changes were consistent with a diagnosis of chronic cholecystitis. The clinical message of this paper is that patients should be observed for this usual complication of hemobilia after liver injury.

Adolescent↗
PubMed1995

Congenital hypothyroidism with delayed rise in serum TSH missed on newborn screening.

We report on a female patient with congenital hypothyroidism (CH) missed on a newborn screening test. She is now 10 years old with retarded development. The patient was born premature at 34 weeks of gestation with birth-weight of 1515 g, and was judged to be normal in the screening programme of Niigata Prefecture. However, she gradually suffered from poor weight gain and retarded development with stridor at breathing. Serum thyroid stimulating hormone (TSH) levels were rechecked and showed high values with normal T3 and T4 levels. She was referred to our hospital at the age of 13 months. She was diagnosed as having CH (ectopic thyroid) with a delayed rise in blood TSH concentration, probably due to the prematurity of the hypothalamic-pituitary-thyroid axis. L-thyroxine therapy brought a decline in TSH levels with partial improvement of her symptoms. Regardless of the result of newborn screening, infants with elevated serum TSH levels should be carefully examined for possible CH, even when T3, T4 and free T4 values are in the normal range.

Child↗
PubMed1995

Screening for neuroblastoma: a 9-year birth cohort-based study in Niigata, Japan.

Between April 1985 and March 1994 (9 years), 229,346 babies were born in Niigata prefecture, and 201,888 (88.0%) underwent mass screening (MS) for neuroblastoma at 6 months of age. To date, 29 infants have been screen-detected as having neuroblastoma (1:7908). All screen-detected patients survived after removal of the primary tumor. In the same birth cohort, 17 additional children were clinically diagnosed as having neuroblastoma. The cumulative incidence rate of neuroblastoma at 5 years of age was 10.5 per 100,000 live births in the 5-year birth cohort before MS was introduced, and 18.6 per 100,000 in the first 5-year birth cohort after MS was introduced. These values were not statistically different. The birth cohort incidence rate increased significantly to 22.2 per 100,000 (p < 5% compared with before MS) after the method of MS was changed to high-power liquid chromatography (HPLC), even though this latest birth cohort has not been followed for 5 years. The population-based mortality rate from neuroblastoma was 5.9 per 100,000 in the 5-year birth cohort before MS, and 4.5 per 100,000 after MS in the first 5-year birth cohort, using the vanillymandelic acid (VMA) spot test. These values were not statistically significant. In contrast, no death was observed in the next 4-year birth cohort after MS using HPLC; however, this birth cohort has not yet been followed for 5 years.

Chi-Square Distribution↗
PubMed1995

A family with adult type ceroid lipofuscinosis (Kufs' disease) and heart muscle disease: report of two autopsy cases.

Two cases in a family with Kufs' disease had lethal arrhythmias and heart muscle disease. Autopsy findings showed an abundant accumulation of lipofuscin-like lipopigments in most neurons in the central nervous system (CNS). The heart showed a slight increase in the accumulation of the lipofuscin-like lipopigments in the myocardial fibers, slight to severe fibrosis and infiltration of fat cells in the myocardium. The lipopigments both in the heart and in neurons of the CNS had curvilinear profiles on electron microscope and reacted immunohistochemically to polyclonal antibodies against subunit c of mitochondrial adenosine triphosphate (ATP) synthase. The degenerative process in this heart muscle disease might be attributable to the same metabolic abnormality as seen in the neuronal degeneration associated with Kufs' disease.

Arrhythmias, Cardiac↗
PubMed1994

Ultrasonically guided percutaneous microwave coagulation therapy for small hepatocellular carcinoma.

BACKGROUND: The authors have used percutaneous microwave coagulation therapy (PMCT) as a new percutaneous local treatment for single unresectable hepatocellular carcinoma (HCC) measuring 2 cm or less in greatest dimension (small HCC). PMCT was used to attempt a cure of the disease. In this study, the efficacy of this treatment was assessed. METHODS: PMCT was performed on 18 patients with single small HCC. A microwave electrode (custom-made, 30-cm long by 1.6-mm thick) was inserted percutaneously into the tumor area under ultrasonic guidance. Microwaves at 60 W for 120 seconds were used to irradiate the tumor and surrounding area. RESULTS: After PMCT was administered, various image findings were correlated with tissue necrosis. At the tumor and surrounding area, ultrasonography showed echogenic change, contrast enhancement disappeared on contrast enhanced computed tomography, and magnetic resonance imaging (T2-weighted image) showed decreased intensity in all cases after treatment. Complete necrosis of the tumor area in a specimen obtained from one patient who underwent hepatectomy after PMCT also was confirmed. The treatment reduced levels of the tumor marker, alpha-fetoprotein, which had been high in some patients. Although the follow-up period was short (11-33 months), 17 patients remain alive. Local recurrence in the treated area has not been detected, and no serious side effects or complications have been encountered. CONCLUSIONS: PMCT may be an effective and safe treatment for small HCCs.

Adult↗
PubMed1994

Disseminated Mycobacterium avium-intracellulare infection in a patient with myelodysplastic syndrome (refractory anemia).

A 31-year-old woman presented with fever and arthralgia. Despite treatment with antimicrobials and corticosteroids, her symptoms persisted. A diagnosis of myelodysplastic syndrome (MDS)-refractory anemia (RA) was made by pancytopenia, dysplasia, and trisomy 8. Cultures of bone marrow, blood, and gastric juice showed Mycobacterium avium-intracellulare (MAI). She was treated with antimycobacterial drugs and recombinant human G-CSF/M-CSF and showed an initial response, but spike fever recurred and pancytopenia progressed. Hepatosplenomegaly and marked retroperitoneal lymphadenopathy were revealed, indicating further dissemination of MAI. Treatment with recombinant human GM-CSF and very-low-dose cytosine arabinoside, was started but was not effective. This case showed significant reduction in peripheral blood T-lymphocytes, especially the CD4+ population, and low immunoglobulin levels. Immunodeficiency state associated with long-term steroid therapy and MDS seemed to contribute to the development of the disseminated infection with MAI.

AIDS-Related Opportunistic Infections↗
PubMed1994

Adoptive immunotherapy mediated by anti-TCR/IL-2-activated tumour-draining lymph node cells.

The adoptive immunotherapy of cancer with sensitized T lymphocytes is well documented in several animal models. These studies indicate the existence of precursor lymphocytes, in the tumour-bearing animals, which can acquire therapeutic efficacy after in vitro manipulations. To generate immune effector cells, these precursor lymphocytes have to be antigenically stimulated in vitro by the tumour of origin. Using the weakly immunogenic MCA 205 and MCA 203 murine sarcomas, we demonstrate here that this in vitro antigenic stimulation can be achieved by sequential activation with anti-T-cell receptor (TCR) monoclonal antibody and interleukin-2 (IL-2). The culture of tumour-draining lymph node (TDLN) cells with anti-TCR/IL-2 resulted in an up to eightfold increase in cell numbers. The adoptive transfer of these activated cells mediated a significant reduction of 3-day established pulmonary metastases. Although this antibody could activate all of the TCR alpha beta-bearing T cells non-specifically, the therapeutic efficacy mediated by anti-TCR/IL-2-activated cells was tumour specific. Treatment of MCA 205 advanced pulmonary metastases resulted in prolongation of survival, and 30% of treated mice were tumour free for more than 90 days. These tumour-free mice rejected a challenge of MCA 205 but not MCA 203, indicating the development of long-lasting systemic tumour immunity. In spite of their in vivo anti-tumour efficacy, the anti-TCR/IL-2-activated TDLN cells did not exhibit detectable in vitro cytotoxicity. These results demonstrate that this activation method could be an alternative way to generating potent anti-tumour effector T cells.

Animals↗