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Biomedical subjects

N Yamanaka

Publications and source records attributed to N Yamanaka.

At least 19 recordsLinked to original sources
PubMed1992

Do the tumor cells of hepatocellular carcinomas dislodge into the portal venous stream during hepatic resection?

BACKGROUND: The current study was undertaken to investigate whether or not tumor cells are dislodged into the portal venous stream during hepatic resection for hepatocellular carcinomas. METHODS: A catheter was placed using echo guidance into the portal branch through the mesenteric vein in 31 patients. Cytologic examinations were done on multiple blood samples at various operative stages. RESULTS: Tumor cells were recovered in 7 of 31 patients in whom the tumor sizes were more than 5 cm and portal invasions were found microscopically and/or macroscopically. By contrast, the remaining 24 tumors were less than 5 cm in size and showed negative portal invasions. Recovery of the tumor cells was found, not during the earlier operative stage of mobilization or rotation of the hepatic lobe, but during the later stages of hilar dissection or hepatic parenchymal dissection. CONCLUSIONS: The portal pedicles should be divided before hepatic dissection in segmentectomy and lobectomy to lessen the chance of dissemination of intravasated tumor cells.

Adult↗
PubMed1992

The prognostic value of Ki-67 antigen in non-Hodgkin lymphoma of Waldeyer ring and the nasal cavity.

BACKGROUND: A monoclonal antibody, Ki-67, recognizes an antigen expressed in all phases of the cell cycle, except G0, and can be used as a simple histologic marker of cell proliferation. To assess the prognostic value of the growth fraction in non-Hodgkin lymphoma of Waldeyer ring (W-NHL) and the nasal cavity (N-NHL), the authors applied Ki-67 immunostaining combined with image analysis on such lymphomas. METHODS: The authors studied 29 patients (18 with W-NHL and 11 with N-NHL), applying Ki-67 to frozen sections. The number of Ki-67-positive cells in a unit area (0.044 mm2), as an indicator of proliferative activity, and the mean area per Ki-67-positive cell (microns2), as an indicator of DNA content, were measured by the image processing system. RESULTS: High-grade lymphomas showed a significantly larger number of Ki-67-positive cells than intermediate-grade lymphomas (102.5 +/- 21.6 in high-grade and 46.8 +/- 8.92 in intermediate-grade lymphomas, P = 0.03), even when analyzed separately by immunophenotypes. A large mean area per Ki-67-positive cell was associated significantly with a T-cell phenotype (36.3 +/- 7.69 microns2 in T-cell lymphomas and 19.4 +/- 2.33 microns2 in B-cell lymphomas, P = 0.034) and an unfavorable clinical outcome. High proliferative activity, defined as nuclear Ki-67 expression in 2000 or more B-cell lymphoma cells and 1000 or more T-cell lymphoma cells in a 1-mm2 area, was found to be a strong predictor of poor survival among these patients (P = 0.048 and P = 0.009, respectively). CONCLUSIONS: Ki-67 immunostaining, combined with image analysis, is a novel method for determining a tumor proliferative index that provides useful clinical data regarding head and neck lymphomas.

Adolescent↗
PubMed1992

Lethal midline granuloma (peripheral T-cell lymphoma) after lymphomatoid papulosis.

A Japanese woman with an 8-year history of lymphomatoid papulosis (LP) had lethal midline granuloma (LMG) develop at the age of 51 years. There were histologic similarities between LP and LMG seen in this patient. Surface phenotypic studies on nasal and cutaneous lesions demonstrated a population of T-cells expressing CD2, CD4, CD25, CD30, and histocompatibility antigen-DR (HLA-DR). Genotypic analyses of nasal and skin biopsy specimens disclosed a clonal rearrangement of the beta T-cell receptor gene with the same rearrangement pattern. These data indicate that this patient had LMG characterized by clonal peripheral T-cell lymphoma, which probably resulted from progression of the LP.

Adult↗
PubMed1992

Factors contributing to phoneme recognition ability of users of the 22-channel cochlear implant system.

A study was carried out to determine which factors contributed to the vowel and consonant recognition ability of recipients of the 22-channel cochlear implant system. On the basis of the statistical analysis, no isolated factor showed a strong correlation with vowel recognition score. On the other hand, negative correlations were found between patients' consonant recognition scores and postoperative psychophysical percepts such as threshold levels and maximum comfortable loudness levels. However, multiple regression analysis also showed that the combination of lower threshold levels, a larger number of usable electrodes, and wider dynamic ranges contributed to higher consonant recognition scores.

Adult↗
PubMed1992

Presence of an 80 kilodalton protein, cross-reacted with monoclonal antibodies to pulmonary surfactant protein A, in the human middle ear.

We report the presence of a middle ear protein that has the same epitope as human surfactant protein A. Monoclonal antibodies (PC-6 and PE-10) against human pulmonary surfactant protein A stained faint granules of the mucosal epithelial cell cytoplasm in the orifice of the eustachian tube immunohistochemically. These antibodies also reacted with middle ear effusion of patients with otitis media with effusion by dot immunoassay, and recognized an 80 kd protein by Western blot analysis. These findings indicate that a protein immunoreactive with PC-6 and PE-10 occurs in the mucosal epithelial cells of the middle ear, and is also present in middle ear effusion. It is therefore likely that this 80 kd protein might be secreted from the mucosal epithelial cells to the middle ear cavity.

Adult↗
PubMed1992

Mesenchymal hamartoma of the liver: report of an adult case and review of the literature.

A case of mesenchymal hamartoma of the liver incidentally found to be a hyperechoic mass by abdominal ultrasonography in a 62-year-old male is described. Computed tomography and magnetic resonance imaging of the liver confirmed the presence of a well-demarcated inhomogeneous mass in the left medial segment. Hepatic arteriography revealed the mass to be generally hypovascular. Histopathologic diagnosis of the resected specimen was a solid form of benign mesenchymal hamartoma, a rather rare lesion for the patient's age. Fifteen adult cases of hepatic mesenchymal hamartoma in the literature including the present case are reviewed.

Diagnosis, Differential↗
PubMed1992

Distribution of lymphoid cells in tonsillar compartments in relation to infection and age. A quantitative study using image analysis.

The distribution of lymphoid cells in the mantle zone, germinal center, interfollicular area, and subepithelial area of the tonsil was evaluated quantitatively by image analysis in 66 subjects aged 3 to 66 years. The number of Ig-positive cells in the tonsil decreased with advancing years in all compartments. This inverse correlation to age was statistically significant for IgD-, IgM-, and IgG-positive cells. For T-cells, overall change of each T-cell subset with age was smaller than those of Ig-positive cells. An age-related marked decline was seen for CD4-positive cells only in the subepithelial area and for CD8-positive cells only in the interfollicular area. Ki-67-positive cells, cells undergoing active division, were mainly found in the germinal centers and also diminished with advancing years. Patients with frequent episodes of tonsillitis demonstrated a significant increase of IgD-positive cells and IgG-positive cells in interfollicular and subepithelial compartments and a decrease of CD4-positive T-cells in the germinal centers and subepithelial areas. These results suggest that the tonsillar involution with age is immunologically associated in all compartments with the decrease of Ig-positive cells and Ki-67-positive activated cells resulting in a relative increase of T-cell subsets. The method of image analysis provides a novel and unique approach for quantitative immunohistological study of the tonsil.

Adolescent↗
PubMed1992

[The advancement of image cytometry in immunohistology].

An image processing system has been developed by the combination of recent electronic and computer technologies. The system may have a potential power for the quantitative analysis on the immunohistology. The image cytometry was applied to quantitative analysis on Ki-67-positive cells in lymphomas of Waldeyer's ring and nasal cavity. High grade lymphomas showed significantly larger number of Ki-67-positive cells than intermediate-grade lymphomas, even analyzed separately by immunophenotypes. A large mean area per Ki-67-positive cell was significantly associated with T-cell phenotype and unfavorable clinical outcome. Thus, Ki-67 immunostaining combined with image cytometry is a novel method for determining a tumor proliferative index which provides useful clinical data of non-Hodgkin's lymphomas.

Cytophotometry↗
PubMed1992

[Genotypic analysis of lethal midline granuloma].

So-called lethal midline granuloma is of great clinical and theoretical interest. The etiology of lethal midline granuloma is unknown and the pathogenesis is variable, with debate as to precise classification and natural history. In this study, we reported genotypic and immunopathological features in 3 cases of lethal midline granuloma. The histopathological diagnosis of their biopsy specimens was initially polymorphic reticulosis/midline malignant reticulosis. Immunohistologic study of the specimens revealed that immature or atypical cells had phenotypes of T-cells, CD2, CD3, CD4 (Case 1), CD4 (Case 2), and CD2, CD3 (Case 3). Those cells were also found to be positive for HLA-DR, which indicated that they were activated T-cells. Immunohistology in T-cells, however, was not able to give a similar clue to clonarity as it was possible within B-cell neoplasms by immunophenotyping the light chains. With the establishment of cDNA probes for the T-cell receptor genes it was possible to analyze neoplasms of lymphocyte origin for lineage and clonality. The Southern blot analysis of 3 cases showed rearrangement of TCR gene, TCR beta and TCR gamma chain (Cases 1 and 2) and TCR beta and TCR delta chain (Case 3), whereas none of them showed rearrangement of immunoglobulin heavy chain. These findings represented conclusive evidence for a monoclonal T-cell proliferation within lethal midline granuloma. On the ground of immunohistological and genotypic studies, lethal midline granuloma histologically diagnosed as polymorphic reticulosis/midline malignant reticulosis are proven to be a T-cell lymphoproliferative disorder.

Adult↗
PubMed1991

Effect of dextrans of various molecular weights on mesangial transport in ddY mice pretreated with sheep anti-type IV collagen serum.

The authors' previous report concluded that increased mesangial IgA deposition seen in ddY mice pretreated with mesangiotropic anti-type IV collagen serum might be due to a dysfunction of mesangial transport of macromolecules such as polymeric autologous IgA. In the present study we examined the effect of macromolecules upon mesangial transport in similarly treated ddY mice, using intravenously administered FITC-labeled dextrans of various molecular weights as tracers. The intensity of each resulting mesangial dextran deposit inspected directly by immunofluorescence was measured periodically and compared with the deposition of autologous mouse IgA examined using rhodamine-labeled rabbit anti-mouse IgA. High-molecular-weight dextran of 2,000 kDa showed prolonged mesangial deposition which paralleled the intensity and distribution of the autologous mouse IgA deposition. In contrast, medium- and low-molecular-weight dextrans of 500 and 150 kDa, respectively, disappeared earlier from the mesangium, unlike the autologous IgA deposition which persisted. Based on these results, it was concluded that the macromolecularity of certain substances and a transport dysfunction of the mesangium may both be major factors in prolonged mesangial deposition. These findings may provide some clues to help clarify the pathogenesis of human IgA nephritis.

Animals↗
PubMed1991

[Qualitative analysis of the immunoreactive hCG beta-like substance produced by transitional cell carcinoma of the bladder].

The hCG beta-like immunoreactivity (IR-hCG beta) in the sera and urine of three patients with transitional cell carcinoma of the bladder was characterized by enzyme-immunoassay which specifically recognized the hCG beta-related molecular species (whole hCG, free hCG beta and beta-core fragment). There was a qualitative difference in IR-hCG beta between the serum and the urine in all of the patients. Free hCG beta was exclusively detected in the serum, whereas both free hCG beta and beta-core fragment (beta-CF) could be detected in the urine. Whole hCG could not be virtually observed in the sera and the urine from all the patients examined. The concentrations of urinary beta-CF were consistently much higher than those of urinary and serum free hCG beta in all the patients. The immunohistochemical study was performed by using two kinds of the antibody against the core and the carboxyterminal portions of the hCG beta molecule. Immunoperoxidase staining was positive not only in the syncytiotrophoblastic giant cells but also in the transitional cell carcinoma cells for both antibodies. The present results suggest that free hCG beta is secreted from the tumor cells and metabolized into beta-CF may provide a new index to detect a transitional cell carcinoma of the bladder.

Aged↗
PubMed1991

[Autotransfusion in hepatectomy for hepatocellular carcinoma].

Experimental data of autotransfusion in hepatectomy for hepatocellular carcinoma and clinical data from forty-eight patients were analyzed. By a density gradient medium, cancer cells banded at a lower density (1.056 g/ml: mean) than red blood cells (1.105 g/ml: mean). The centrifuge autotransfusor separated the red blood cells from cancer cells and all sections of cell blocks of the blood harvested intraoperatively in 20 cases revealed no malignant cells. The average requirement of bank blood was significantly reduced in these patients than in patients without autotransfusion during one year before, 1573 ml to 478 ml (whole blood of concentrated red blood cells) (p less than 0.05). These findings indicate that autotransfusion in hepatectomy for hepatocellular carcinoma is safe and practical.

Blood Transfusion, Autologous↗
PubMed1991

[Treatment of hepatocellular carcinoma from the aspect of nuclear DNA analysis].

Flow cytometric DNA analysis was done on 302 resected hepatocellular carcinoma and 30 specimens by fine needle aspiration biopsy. Patients with DNA aneuploid tumors had a significant worse prognosis than those with DNA diploid tumors in subdivided groups by curability (p less than 0.01). The recurrence after hepatectomy occurred frequently in DNA aneuploid or non-curative resected group. In a cox multivariate analysis, nuclear DNA content provided significant prognostic value (p = 0.008) as did vascular invasion and intrahepatic metastasis. For the multiple tumors of hepatocellular carcinoma, it is helpful to get the DNA ploidy pattern to diagnose tumors with intrahepatic metastasis or multicentric origin. Nuclear DNA analysis by fine needle aspiration biopsy was useful to determine the treatment method of hepatocellular carcinoma.

Carcinoma, Hepatocellular↗
PubMed1991

[Effect of KT-611 (Naftopidil) on the contraction of human prostatic tissue and its use in benign prostatic obstruction].

A new alpha 1-adrenergic receptor antagonist, KT-611 (naftopidil) antagonized dose dependently the contraction induced by agonists, noradrenaline and phenylephrine in the human prostatic tissue. KT-611 at a dosage of once or twice a day was evaluated for its effects on 49 patients with benign prostatic hypertrophy. The drug improved subjective and objective symptoms significantly. The residual urine was reduced in volume and percentage significantly. The average and maximum flow rates increased significantly. The optimal dosage was presumed to be in the range of 25 to 75 mg once a day or 25 to 100 mg twice a day. Adverse reactions and abnormal laboratory findings were all slight. KT-611 was concluded to be useful in the treatment of patients with benign prostatic hypertrophy.

Adrenergic alpha-Antagonists↗