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J Nakayama

Publications and source records attributed to J Nakayama.

At least 55 records · Page 3Linked to original sources
PubMed2001

[Mediastinal cystic lesions: CT and MRI findings].

In this article we describe various approaches to the evaluation of mediastinal cystic lesions using CT and MRI. Although cystic lesions generally appear to be uncomplicated and not difficult to diagnose, we consider that there are certain pitfalls in differentiating them from solid lesions. It is important to pay careful attention to the location (including ectopic occurrence), CT attenuation and/or MR intensity, thickness of the wall, tear-drop shape or alternation of shape owing to intrathoracic pressure, and pseudoenhancement. We suggest that MR be recommended when the findings of CT are equivocal, as they were in 32 of our cases.

Adult↗
PubMed2001

[Clinical efficacy of treatment with low-dose flutamide in maximum androgen blockade therapy].

To prevent treatment withdrawal due to flutamide-induced liver dysfunction, we performed maximum androgen blockade (MAB) therapy by combining a luteinizing hormone-releasing hormone agonist or orchiectomy with low-dose flutamide (125 mg x 2/day) in patients with prostate cancer. In this study, the efficacy, adverse effects such as hepatotoxicity, and compliance were compared retrospectively between 35 patients who received low-dose flutamide therapy (1995-1999) and 27 patients who received flutamide at its ordinary dose (125 mg x 3/day). No significant difference was observed in the response rate (> or = PR) as determined from the prostate-specific antigen parameter (p = 0.6211) or the incidence of hepatotoxicity based on the aspartate aminotransferase and alanine aminotransferase levels. However, flutamide withdrawal due to liver dysfunction was less frequent in the low-dose group (2.9%) than in the ordinary dose group (18.5%) (p = 0.0386). MAB therapy using low-dose flutamide is expected to prevent the reduction in the compliance due to side effects and to improve the long-term prognosis in patients with prostate cancer, who are mostly elderly individuals.

Aged↗
PubMed2001

[Evaluation of dermatological symptoms of Yusho patients in the annual examination in 1999-2000].

We analyzed the severity grades of the skin symptoms of Yusho patients who visited the annual examinations in 1999 and 2000. The severity grades of the skin symptoms clearly improved. The patients graded as 0 increased and those graded as II.III-III or III.IV-IV decreased as compared to the data in 1993. The pattern of the skin severity scores did not change much, although the patients who showed 0.1 reached 68% in 2000. The blood PCB concentration of Yusho patients also clearly decreased, especially in the patients who showed "A" pattern. Furthermore, the skin changes of the aged patients should be analyzed in detail in the future.

Female↗
PubMed2000

Immuno-histochemical detection of human telomerase reverse transcriptase in human liver tissues.

Although telomerase activity in hepatocellular carcinoma (HCC) increases in accordance with degree of histological undifferentiation, it is unknown whether the level of telomerase activity in HCC reflects of the degree of activity in individual cells or the frequency of telomerase-positive HCC cells. Non-cancerous liver tissues exhibit low but significant levels of telomerase activity, but the nature of telomerase-positive cells in these tissues is unclear. In this study, we performed immunohistochemical staining using specific antibody against telomerase reverse transcriptase (hTERT) protein in 15 HCC samples and 13 adjacent non-cancerous liver tissues. There were hTERT-positive hepatocytes, though very low frequency, in non-cancerous liver tissues. The frequencies in hTERT positive hepatocytes were very well correlated with clinicopathological parameters and telomerase activity levels: the average frequencies of chronic hepatitis was 0.2%, liver cirrhosis 0.2%, well-differentiated HCC 3.0%, moderately differentiated HCC 28%, and poorly differentiated HCC 95%. The intensity of staining varied among cells within a given specimen, and correlation with degree of histological undifferentiation was less obvious. Portions of migrating lymphocytes and biliary epithelial cells were also hTERT-positive. These findings indicate that the upregulation of telomerase activity with degree of undifferentiation of HCC is mainly due to the increase in frequency of hTERT positive HCC cells.

Carcinoma, Hepatocellular↗
PubMed2000

Minimum 10-year outcome of decompressive laminectomy for degenerative lumbar spinal stenosis.

STUDY DESIGN: A retrospective follow-up study was conducted in patients who underwent decompressive laminectomy for degenerative lumbar spinal stenosis. OBJECTIVES: To describe the long-term outcome of decompressive laminectomy performed for degenerative lumbar spinal stenosis, and to investigate preoperative factors that influenced outcomes, especially risk factors predisposing patients to poor results. SUMMARY OF BACKGROUND DATA: The success rate of surgical treatment of decompressive laminectomy for lumbar spinal stenosis varies. Long-term follow-up investigations have indicated deterioration of outcome; however, the causes of deterioration have not been fully investigated, and there have been no reports with a minimum 10-year follow-up. METHODS: Of 151 patients who underwent decompressive laminectomy from 1980 through 1989, 37 were followed up for a minimum of 10 years. The mean age at surgery was 60.9 +/- 8. 2 years (range, 43-76), and the average follow-up period was 13.1 +/- 2.1 years (range, 10.1-17.4). The results were evaluated by the criteria of the Japanese Orthopedic Association Lumbar Score, and the outcome was classified as excellent at more than 75% improved score; good, 50-75%; fair, 25-49%; and poor, 0-24% or less. Information about impairment of activities of daily living was also obtained at follow-up. Associations between preoperative clinical and radiographic variables and clinical outcome were evaluated statistically. RESULTS: In all patients, the average score improvement of 55.2 +/- 31.6% was regarded as acceptable. The postoperative score and percentage of improvement of low back pain were lower than those of leg pain and walking ability. No impairment in activities of daily living was found in 62.2% of the patients. Rate of improvement was evaluated as excellent in 13 (35.1%), good in 8 (21.6%), fair in 8, and poor in 8 patients. Three patients required additional surgery because of disc herniation at the laminectomied segments. The patients with multiple laminectomy (P = 0.034) and more than 10 degrees preoperative sagittal rotation angle (P = 0.018) showed a significantly poorer outcome than the remainder of the patients. CONCLUSIONS: Long-term follow-up showed that even without spinal fusion, more than half the patients were evaluated as excellent or good. Patients with more than a 10 degrees sagittalrotation angle who need multiple laminectomy, should be given information about the possibility of earlier deterioration of the outcome, and alternative or additional treatment such as concomitant spinal fusion with decompression may be considered.

Activities of Daily Living↗
PubMed2000

Expression of polysialic acid and STX, a human polysialyltransferase, is correlated with tumor progression in non-small cell lung cancer.

Polysialic acid (PSA) is a carbohydrate composed of a linear homopolymer of alpha-2-8-linked sialic acid residues and is mainly attached to the neural cell adhesion molecule (NCAM). Because of the large negative charge of PSA, presence of PSA attenuates the adhesive property of NCAM and increases the cellular motility. PSA expression on NCAM is developmentally regulated, and PSA plays important roles in formation and remodeling of the neural system through regulation of the adhesive property of NCAM. Expression of the polysialated form of NCAM has been also demonstrated in some malignant tumors, such as Wilms' tumor and small cell lung cancer. Despite the possible importance as an onco-developmental antigen, however, significance of PSA expression in most malignant tumors has not been revealed. Therefore, PSA expression in non-small cell lung cancer was assessed in the present study. PSA was expressed only in 5 (20.8%) of 24 pathological stage I cases, whereas it was expressed in most stage IV cases (76.8%, 11 of 14 cases). PSA expression was correlated with nodal metastasis and distant metastasis, but not with local extent of the primary tumor. Next, expression of polysialyltransferase genes (PST and STX genes) which controlled formation of PSA, was examined. The PST gene was constantly expressed in both normal lung tissue and tumor tissue of all cases. In contrast, the STX gene was not expressed in normal lung tissue of any case, and STX gene expression in tumor tissue was closely correlated with tumor progression. The STX gene was expressed only in 1 (4.2%) of 24 stage I cases, whereas it was expressed in most stage IV cases (85.7%, 12 of 14 cases). These results suggested that the PSA and STX genes could be new targets of cancer therapy as well as important clinical markers.

Adult↗
PubMed2000

A chromodomain protein, Swi6, performs imprinting functions in fission yeast during mitosis and meiosis.

Inheritance of stable states of gene expression is essential for cellular differentiation. In fission yeast, an epigenetic imprint marking the mating-type (mat2/3) region contributes to inheritance of the silenced state, but the nature of the imprint is not known. We show that a chromodomain-containing Swi6 protein is a dosage-critical component involved in imprinting the mat locus. Transient overexpression of Swi6 alters the epigenetic imprint at the mat2/3 region and heritably converts the expressed state to the silenced state. The establishment and maintenance of the imprint are tightly coupled to the recruitment and the persistence of Swi6 at the mat2/3 region during mitosis as well as meiosis. Remarkably, Swi6 remains bound to the mat2/3 interval throughout the cell cycle and itself seems to be a component of the imprint. Our analyses suggest that the unit of inheritance at the mat2/3 locus comprises the DNA plus the associated Swi6 protein complex.

Cell Cycle↗
PubMed2000

Linkage of human narcolepsy with HLA association to chromosome 4p13-q21.

Although narcolepsy is highly associated with human leukocyte antigen (HLA) DQ6/DQB1*0602 and/or DR2/DRB1*1501, most individuals with the HLA haplotype are free of narcolepsy. This indicates that HLA alone makes a relatively small contribution to the development of narcolepsy and that a non-HLA gene(s) can contribute to the genetic predisposition even in narcoleptic cases with HLA association. We conducted a genome-wide linkage search for narcolepsy in eight Japanese families with 21 DR2-positive patients (14 narcoleptic cases with cataplexy and 7 cases with an incomplete form of narcolepsy). A lod score of 3.09 suggested linkage to chromosome 4p13-q21. A lod score of 1.53 was obtained at the HLA-DRB1 locus, though this lod score may be biased since all the affected patients and many of the family members were DR2-positive. No other loci including hypocretin, hypocretin receptor 1, and hypocretin receptor 2 had lod scores greater than 1.0. The present study suggests that chromosome 4p13-q21 contains a second locus for HLA-associated human narcolepsy.

Chromosome Mapping↗
PubMed2000

Synthesis and Physical Properties of Sterically Congested Cycloalkenes, 1,2-Di-tert-butyl-3,3,5,5-tetramethylcyclopentene and 1,2-Di-tert-butyl-3,3,6,6-tetramethylcyclohexene.

Two sterically congested cycloalkenes (9 and 10), congeners of tetra-tert-butylethylene, were synthesized and characterized. Oxidation of the bicyclic 1,3-dithietane 8 with dimethyldioxirane (DMD) gave the endo,endo-disulfoxide 13, thermal isomerization of which to the endo,exo-disulfoxide 15 followed by oxidation with DMD gave the trioxide 18. Heating 18 in refluxing 1,3-dimethyl-2-imidazolidinone furnished 1,2-di-tert-butyl-3,3,5,5-tetramethylcyclopentene (9) in 69% yield by a 2-fold extrusion process. The reaction of the 1,6-diketone dihydrazone 23 with Se(2)Cl(2) gave the selenadiazoline 34 and the 1,3-diselenetane 35. Heating 34 at 115-130 degrees C gave 1,2-di-tert-butyl-3,3,6,6-tetramethylcyclohexene (10), a "didehydro" derivative of tetra-tert-butylethylene, in 43% yield. The C=C bond in 10 is strained in degree comparable to those of most strained alkenes reported so far.

Journal Article↗
PubMed2000

Macrophage infiltration correlates with tumor stage and angiogenesis in human malignant melanoma: possible involvement of TNFalpha and IL-1alpha.

We examined whether macrophage infiltration is associated with angiogenesis in cutaneous melanoma. The numbers of macrophages and microvessels increased significantly with increasing depth of tumor and with tumor angiogenesis. Macrophage infiltration thus appeared to provide a useful diagnostic marker for the progression of cutaneous melanoma. We further examined whether human melanoma cells produce angiogenic factors in response to macrophage-derived cytokines, tumor necrosis factor alpha (TNFalpha) and interleukin-1 alpha (IL-1alpha). Treatment of melanoma cells with TNFalpha and IL-1alpha in vitro enhanced the production of interleukin-8 (IL-8) and vascular endothelial growth factor (VEGF), and of basic fibroblast growth factor (bFGF) to a lesser degree, in human melanoma cells. Lipopolysaccharide (LPS)-activated human monocytes enhanced production of IL-8, VEGF, TNF alpha, as well as IL-1alpha, but not bFGF. Co-culture of human monocytes and human melanoma cells was also found to significantly enhance production of IL-8 and VEGF in the absence and presence of LPS, compared with either monocytes or melanoma cells alone. The production of IL-8 and VEGF from co-cultured melanoma cells and LPS-activated monocytes was blocked when anti-TNF-alpha antibody or anti-IL-1alpha antibody was co-administrated. This is direct evidence that production of the potent angiogenic factors IL-8 and VEGF from melanoma cells is up-regulated through TNFalpha and/or IL-1alpha secreted by activated monocytes/macrophages, influencing both tumor growth and angiogenesis in melanomas.

Adult↗
PubMed2000

Significant evidence for linkage of febrile seizures to chromosome 5q14-q15.

Febrile seizures (FSs) represent the most common form of childhood seizure. In the Japanese population, the incidence rate is as high as 7%. It has been recognized that there is a significant genetic component for susceptibility to this type of seizure. Two putative FS loci, FEB1 (chromosome 8q13-q21) and FEB2 (chromosome 19p), have been mapped. Furthermore, a mutation in the voltage-gated sodium (Na(+))-channel beta1 subunit gene ( SCN1B ) at chromosome 19q13.1 was identified in a family with a clinical subset, termed generalized epilepsy with febrile seizures plus (GEFS(+)). These loci are linked to some large families. In this study, we conducted a genome-wide linkage search for FS in one large family with subsequent linkage confirmation in 39 nuclear families. Significant linkage was found at D5S644 by multipoint non-parametric analysis using GENEHUNTER ( P = 5.4 x 10(-6)). Estimated lambda(s)at D5S644 was 2.5 according to maximum likelihood analysis. Significant linkage disequilibria with FS were observed at the markers D5S644, D5S652 and D5S2079 in 47 families by transmission disequilibrium tests. These findings indicate that there is a gene on chromosome 5q14-q15 that confers susceptibility to FSs and we call this gene FEB4.

Child, Preschool↗
PubMed2000

Coexistence of gland mucous cell-type mucin and lysozyme in gastric gland mucous cells.

Class III mucin, identified by paradoxical concanavalin A staining, is confined to gastric gland mucous cells and is an essential component of the gastric surface mucous gel layer. The pretreatment required has hampered the application of this method to electron microscopic studies. Antibody HIK1083 reacts selectively with class III mucins. The present study was undertaken to explore, electron microscopically, the immunoreactivity of the human stomach to HIK1083. We examined normal mucosa from resected human stomachs (five cases; formalin-fixed, paraffin-embedded) and gastric biopsy specimens from patients with early gastric cancer [nine cases; glutaraldehyde- and osmium-fixed, epoxy-embedded (seven cases) and half-strength Karnovsky's solution-fixed, Lowicryl K4M-embedded (two cases)]. Immunostaining with HIK1083 and anti-lysozyme antibody was examined under light and electron microscopes. Gland mucous cells were labeled with HIK1083, and lysozyme was detected in some gland mucous cells and surface mucous cells. Electron microscopically, the secretory granules of gland mucous cells contained a single electron-dense core. HIK1083-positive mucins and lysozyme coexisted in the secretory granules of gastric gland mucous cells. HIK1083-reactive mucins and lysozyme were distributed in the matrix and in the dense core of these secretory granules, respectively. HIK1083 can be used for electron immunohistochemistry.

Antibodies↗
PubMed2000

Current techniques of hyperthermic isolated limb perfusion for malignant melanoma.

A retrospective study was conducted examining 25 patients with malignant melanoma who were treated by our new protocol for hyperthermic isolated limb perfusion. The characteristics of our techniques include: a lower priming volume of the extracorporeal circuit; a therapeutic temperature range of 40-41 degrees C with 60 min hyperthermic perfusion; a nominal perfusion flow rate of 500 ml/min in the lower limb and 200 ml/min in the upper limb; and combined carboplatin with interferon-beta as the adjuvant chemotherapy drug. In the lower extremity group, the arterial cannula size ranged from 8 to 14 F, while the venous cannula size ranged from 14 to 16 F. In the upper limb group, the arterial cannula size ranged from 6 to 8F and the venous cannula size ranged from 10 to 12F. No patient required any homologous blood transfusion postoperatively. No operative death or major complications occurred during the early postoperative period, confirming the safety of this treatment. Both optimal cannula size selection and maintaining perfusion temperature below 41 degrees C were judged to be important in elimination of vascular and deep tissue injury.

Adult↗
PubMed2000

Human malignant melanoma cells release a factor that inhibits the expression of smooth muscle alpha-actin.

Smooth muscle alpha-actin (SMA) is a cytoskeletal protein expressed in vascular smooth muscle cells, pericytes, hair follicle dermal sheaths and myofibroblasts which appear in the process of wound healing and tumor growth. To examine the effect of malignant melanoma on the expression of SMA in these non-neoplastic cells, we carried out immunohistochemical staining and a cell culture study. Conditioned medium prepared from a melanoma cell line M14 was incubated with a rat fibroblastic cell line 3Y1, which had been shown to express SMA. Human cells that had migrated from nevus tissue were also cultured either with or without M14 conditioned medium. Immuno-histochemical staining of human melanoma tissues suggested that the expression of SMA was low in the vicinity of the tumor as well as within the tumor nodules. The conditioned medium from melanoma, but not the medium from control non-neoplastic cells, suppressed the expression of SMA both in the 3Y1 cells and human cells that migrated from the nevus. Preincubation of the medium with anti-platelet-derived growth factor allowed 76% recovery of SMA expression. These data thus imply that melanoma cells release a platelet-derived growth factor-like substance which has a suppressive effect on the contractile elements in non-neoplastic cells.

Actins↗
PubMed2000

Macular corneal dystrophy type I and type II are caused by distinct mutations in a new sulphotransferase gene.

Macular corneal dystrophy (MCD; MIM 217800) is an autosomal recessive hereditary disease in which progressive punctate opacities in the cornea result in bilateral loss of vision, eventually necessitating corneal transplantation. MCD is classified into two subtypes, type I and type II, defined by the respective absence and presence of sulphated keratan sulphate in the patient serum, although both types have clinically indistinguishable phenotypes. The gene responsible for MCD type I has been mapped to chromosome 16q22, and that responsible for MCD type II may involve the same locus. Here we identify a new carbohydrate sulphotransferase gene (CHST6), encoding an enzyme designated corneal N-acetylglucosamine-6-sulphotransferase (C-GlcNAc6ST), within the critical region of MCD type I. In MCD type I, we identified several mutations that may lead to inactivation of C-GlcNAc6ST within the coding region of CHST6. In MCD type II, we found large deletions and/or replacements caused by homologous recombination in the upstream region of CHST6. In situ hybridization analysis did not detect CHST6 transcripts in corneal epithelium in an MCD type II patient, suggesting that the mutations found in type II lead to loss of cornea-specific expression of CHST6.

Amino Acid Sequence↗
PubMed2000

Proliferation-associated expression of the MEN1 gene as revealed by in situ hybridization: possible role of the menin as a negative regulator of cell proliferation under DNA damage.

The gene responsible for multiple endocrine neoplasia type 1 (MEN1) has recently been identified. Wide expression of the MEN1 gene in endocrine and non-endocrine organs examined by northern blotting has been reported, but the detailed cellular distribution of the MEN1 transcript in each tissue has not yet been examined in any species. In this report, expression of the MEN1 gene in adult human tissues was studied by in situ hybridization. The MEN1 transcript was widely observed in all tissues examined, and an enhanced expression in relation to cell proliferation was seen in some organs. Cell cycle arrest at the G1-S border reduced the MEN1 mRNA level to less than 50% of that in exponentially growing asynchronous cells. The expression increased as cells entered into S phase, indicating cell cycle-associated transcriptional regulation of the MEN1 gene. Increase or decrease of the amount of menin did not affect proliferation of CHO cells under normal conditions. However, when cells were exposed to the DNA-cross-linking agent, diepoxybutane, overexpression of wild-type menin inhibited DNA synthesis. This effect was not observed when cells were exposed to ultraviolet light. These results suggest that menin may negatively regulate cell cycle under certain DNA damage.

Adult↗