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S Kondo

Publications and source records attributed to S Kondo.

At least 127 records · Page 7Linked to original sources
PubMed2001

Eccrine syringofibroadenoma: case report and review of the literature.

Eccrine syringofibroadenoma (ESFA) is a rare disorder that shows differentiation toward eccrine sweat apparatus. There is a controversy concerning the pathogenesis and differentiation of this tumour. We report a case of ESFA in a 63-year-old Japanese man. We review the literature presenting a classification, including a newly reported subtype. Clinically and pathogenically, ESFA is probably a group of heterogeneous disorders.

Adenoma, Sweat Gland↗
PubMed2001

Electroencephalographic characterization of an adult rat model of radiation-induced cortical dysplasia.

PURPOSE: Cortical dysplasia (CD) is a frequent cause of medically intractable focal epilepsy. The mechanisms of CD-induced epileptogenicity remain unknown. The difficulty in obtaining and testing human tissue warrants the identification and characterization of animal model(s) of CD that share most of the clinical, electroencephalographic (EEG), and histopathologic characteristics of human CD. In this study, we report on the in vivo EEG characterization of the radiation-induced model of CD. METHODS: Timed-pregnant Sprague-Dawley rats were irradiated on E17 using a single dose of 145 cGy or left untreated. Their litters were identified and implanted with bifrontal epidural and hippocampal depth electrodes for prolonged continuous EEG recordings. After prolonged EEG monitoring, animals were killed and their brains sectioned and stained for histologic studies. RESULTS: In utero-irradiated rats showed frequent spontaneous interictal epileptiform spikes and spontaneous seizures arising independently from the hippocampal or the frontal neocortical structures. No epileptiform or seizure activities were recorded from age-matched control rats. Histologic studies showed the presence of multiple cortical areas of neuronal clustering and disorganization. Moreover, pyramidal cell dispersion was seen in the CA1>CA3 areas of the hippocampal formations. CONCLUSIONS: Our results further characterize the in vivo EEG characteristics of the in utero radiation model of CD using long-term EEG monitoring. This model may be used to study the molecular and cellular changes in epileptogenic CD and to test the efficacy of newer antiepileptic medications.

Animals↗
PubMed2001

Migration of 4-nonylphenol from polyvinyl chloride food packaging films into food simulants and foods.

Migration of 4-nonylphenol (NP) from polyvinyl chloride (PVC) films for food packaging into food simulants and foods has been studied in domestic applications such as wrapping of food and reheating in a microwave oven. The migration of NP from the PVC films was determined by high-performance liquid chromatography with electrochemical coulometric-array detection (LC/ED). Twelve PVC films intended for commercial use and ten for domestic applications (total: 22 samples) were analysed. Some of the PVC films (two home-use and ten retail-use) contained NP at concentrations of between 500 and 3300 microg/g. Migration of NP from the films was influenced by the test conditions (n-heptane at 25 degrees C for 60 min, distilled water at 60 degrees C for 30 min and 4% acetic acid at 60 degrees C for 30 min). The amount of NP migrating from the PVC films into n-heptane (0.33-1.6 microg/cm2) was higher than the amount migrating into distilled water or 4% acetic acid (up to 9.7 ng/cm2) for the 11 films in which NP was detected. Up to 0.23% of the NP migrated into distilled water and 4% acetic acid and up to 62.5% into n-heptane. In addition, we investigated NP migration into cooked rice samples wrapped in PVC film. Using spiked samples the method gave an average recovery of 83.7% (n = 5) with a standard deviation of 2.5%. Migration of NP ranged from not detectable (< 1.0 ng/g) to 410.0 ng/g by reheating samples in a microwave oven for 1 min and from not detectable to 76.5 ng/g by keeping samples at room temperature for 30 min.

Chromatography, High Pressure Liquid↗
PubMed2001

Threshold effect for teratogenic risk of radiation depends on dose-rate and p53-dependent apoptosis.

PURPOSE: To obtain evidence that the p53 gene is indispensable for reduction of high teratogenic risk of radiation at a high dose-rate to zero risk by lowering the dose-rate. MATERIALS AND METHODS: Wild-type p53(+/+), heterozygous p53(+/-) and null p53(-/-) mice were exposed to gamma-rays at high or low dose-rates during days 9.5-10.5 of gestation. The incidence of malformations and prenatal deaths was studied. Frequencies of cells dying by apoptosis were measured during or after protracted irradiation. RESULTS: After irradiation with 2 Gy, the frequency of apoptotic cells increased to 20% for p53(+/+) mice and did not increase at all for p53(-/-) mice. For p53(+/+) mice, 2 Gy y-rays induced 70% malformations when given at 1.06 Gy/min, but no malformations above the control when given at 1.2 mGy/min. In contrast, after irradiation of p53(-/-) foetuses with 2 Gy at 1.2mGy/min, the incidence of malformations increased 12% above control levels. CONCLUSION: Foetal irradiation with 2 Gy at 1.2 mGy/min was not teratogenic for p53(+/+) mice but teratogenic for p53(-/-) mice. This indicates that the p53 gene is indispensable for a threshold effect in the risk of radiation at low doses or dose-rates.

Animals↗
PubMed2001

An electron spin resonance study on alkylperoxyl radical in thin-sliced renal tissues from ferric nitrilotriacetate-treated rats: the effect of alpha-tocopherol feeding.

Formation of excess free radical causes cellular oxidative stress, which has been shown to be associated with a variety of pathologic conditions. While electron spin resonance (ESR) spectroscopy has been the only method to demonstrate the presence of free radicals, its application to tissue samples has been challenging. We report here the successful ESR detection in thin-sliced fresh tissues or frozen sections in a rat model. Ferric nitrilotriacetate (Fe-NTA) induces oxidative renal tubular damage that ultimately leads to high incidence of renal carcinoma in rodents. Twenty minutes after administration of 5 mg iron/kg Fe-NTA to rats, a thin-slice of the kidney was mounted on a tissue-type cell and analyzed by ESR spin trapping with 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). An ESR signal from alkylperoxyl radical adduct was obtained, and the signal was inversely proportional to renal alpha-tocopherol content which was modulated through diet. Furthermore, we undertook ex vivo study using frozen sections. Fe-NTA (1 mM) was added to a rat kidney frozen section for 10 min. After washing the specimen was mounted on a tissue-type cell and analyzed with ESR spin trapping using DMPO. Alkylperoxyl radical signal was dependent on thickness, incubation time and renal tissue levels of alpha-tocopherol, and was reduced by preincubation with catalase or dimethyl sulfoxide but not with alpha-tocopherol outside tissue. This versatile method facilitates identification of free radicals in pathologic conditions, and may be useful for selection of antioxidants.

Animals↗
PubMed2001

Cell-type-specific trans-activation of herpes simplex virus thymidine kinase promoter by the human T-cell leukemia virus type I Tax protein.

The human T-cell leukemia virus type I Tax protein (HTLV-I Tax) is known as a trans-activating factor for a variety of genes, including those of cytokines. Here, we show that Tax is capable of activating the herpes simplex virus thymidine kinase (HSV-TK) promoter in certain mammalian cell lines. In murine NIH 3T3 fibroblasts and human HeLa cells, trans-activation by Tax was remarkably strong, whereas in human chondrocytic HCS-2/8 and monkey kidney Cos-7 cells, the responsiveness of the TK promoter to Tax was poor. Deletion analysis revealed that one of the two previously described Sp1 sites is required for the Tax responsiveness, whereas the CTF binding site is not. The results suggest possible interactions between the oncogenic Tax protein and the viral TK in coinfected cells in vivo. Care should be taken in the context of HTLV-I research, as the HSV-TK promoter has been widely used in molecular biology and gene therapeutics.

3T3 Cells↗
PubMed2001

Dual-tagging gene trap of novel genes in Drosophila melanogaster.

A gene-trap system is established for Drosophila. Unlike the conventional enhancer-trap system, the gene-trap system allows the recovery only of fly lines whose genes are inactivated by a P-element insertion, i.e., mutants. In the gene-trap system, the reporter gene expression reflects precisely the spatial and temporal expression pattern of the trapped gene. Flies in which gene trap occurred are identified by a two-step screening process using two independent markers, mini-w and Gal4, each indicating the integration of the vector downstream of the promoter of a gene (dual tagging). mini-w has its own promoter but lacks a polyadenylation signal. Therefore, mini-w mRNA is transcribed from its own promoter regardless of the vector integration site in the genome. However, the eyes of flies are not orange or red unless the vector is incorporated into a gene enabling mini-w to be spliced to a downstream exon of the host gene and polyadenylated at the 3' end. The promoter-less Gal4 reporter is expressed as a fusion mRNA only when it is integrated downstream of the promoter of a host gene. The exons of trapped genes can be readily cloned by vectorette RT-PCR, followed by RACE and PCR using cDNA libraries. Thus, the dual-tagging gene-trap system provides a means for (i) efficient mutagenesis, (ii) unequivocal identification of genes responsible for mutant phenotypes, (iii) precise detection of expression patterns of trapped genes, and (iv) rapid cloning of trapped genes.

Animals↗
PubMed2001

Expression of the cdc25B mRNA correlated with that of N-myc in neuroblastoma.

BACKGROUND: Neuroblastoma is one of the most common solid tumors in early childhood. Overexpression of the proto-oncogene N-myc has been reported to be correlated with more malignant course of the disease. cdc25B is reported to be a target of myc and elevated in several malignant cells and tissues. METHODS: Expression of cdc25B and N-myc messenger RNAs were evaluated by real-time reverse transcription polymerase chain reaction (RT-PCR) assay in 20 tumor samples from neuroblastoma using LightCycler. The data were analyzed with reference to clinicopathological factors. Immunohistochemistry for cdc25B was also performed. RESULTS: There was no significant difference in the cdc25B expression between patient groups according to age, gender and clinical stage. The cdc25B mRNA expression levels were significantly correlated with N-myc mRNA levels (y = -0.445 + 20.577x, p < 0.0001). CONCLUSION: We could not establish the clinical significance to determine the cdc25B mRNA level from neuroblastoma. However, we suggest that cdc25B may play an active role as a target of N-myc in neuroblastoma, although the biological function of cdc25B in neuroblastoma remains to be clarified.

Cell Cycle Proteins↗
PubMed2001

Studies on the hydrolyzing mechanism for cyclodextrins of Thermoactinomyces vulgaris R-47 alpha-amylase 2 (TVAII). X-ray structure of the mutant E354A complexed with beta-cyclodextrin, and kinetic analyses on cyclodextrins.

Crystals of the mutant E354A of Thermoactinomyces vulgaris R-47 alpha-amylase 2 (TVAII) complexed with beta-cyclodextrin were prepared by a soaking method, and the diffraction data were collected at 100 K, using Synchrotron radiation (SPring-8). The crystals belong to an orthorhombic system with the space group P2(1)2(1)2(1) and cell dimensions a = 111.1 A, b = 117.7 A, c = 113.3 A, which is almost isomorphous with crystals of the wild-type TVAII, and the structure was refined to an R-factor = 0.208 (R(free) = 0.252) using 3.0 A resolution data. The refined structure shows that the interactions between Phe286 and two C6 atoms of beta-cyclodextrin at the hydrolyzing site are important for TVAII to recognize cyclodextrins as substrates. This observation from the X-ray structure was supported by kinetic analyses of cyclodextrins using the wild-type TVAII, the mutant F286A and F286L. These studies also suggested that the TVAII-hydrolyzing mechanism for cyclodextrins is slightly different from that for starch.

Amino Acid Substitution↗
PubMed2001

Regulatory mechanism of human connective tissue growth factor (CTGF/Hcs24) gene expression in a human chondrocytic cell line, HCS-2/8.

CTGF/Hcs24 is a multi-functional growth factor that potentiates either the growth or differentiation of mesenchymal cells, according to the biological conditions. Among various functional aspects of CTGF/Hcs24, it is especially notable that CTGF/Hcs24 may promote endochondral ossification in growth cartilage through all stages, and it is highly expressed in a human chondrosarcoma-derived chondrocytic cell line (HCS-2/8). In this study, to clarify the regulatory mechanism of CTGF/Hcs24 gene expression in chondrocytes, we analyzed the transcriptional activity of the CTGF/Hcs24 promoter and the effect of the CTGF/Hcs24 3'-untranslated region (3'-UTR) on gene expression in HCS-2/8 by means of an established DNA transfection and luciferase reporter gene assay system. As a result, the luciferase activity of the CTGF/Hcs24 promoter was found to be remarkably high in HCS-2/8. The 3'-UTR of the CTGF/Hcs24 gene strongly repressed the luciferase activity in HCS-2/8, when it was linked to the downstream of the luciferase reporter gene, suggesting its functionality also in chondrocytic cells. Deletion analysis of the CTGF/Hcs24 promoter clarified a major segment responsible for the enhanced CTGF/Hcs24 promoter activity in HCS-2/8. The TGF-beta response element in the DNA segment was active in HCS-2/8, and point mutations in the element moderately decreased the highly maintained promoter activity with total loss of TGF-beta responsiveness. These results indicate that the strong expression of the CTGF/Hcs24 gene in HCS-2/8 was mainly caused by high transcriptional activity of the CTGF/Hcs24 promoter, and that the TGF-beta response element is one of the critical elements that support the high transcription activity.

3' Untranslated Regions↗
PubMed2001

Treatment of Bowen disease using the ultrasonic surgical aspirator.

In most cases, patients with Bowen disease lesions can be easily treated by surgical excision and direct closure; however, the ultrasonic surgical aspirator, an instrument in common use in many fields, offers a good treatment alternative with few drawbacks for patients with lesions that are large and/or located in joint areas, areas that are hard to heal, or areas that are surgically problematic such as the ears, nose, eyelids, and mucous membranes. The clinical application of the ultrasonic surgical aspirator in the treatment of Bowen disease promises considerable benefit in terms of patient comfort because removal of the lesion is easy, is noninvasive, and does not require hospitalization or result in restricted mobility. All of these factors, although benefiting patients, particularly the elderly, can also substantially lower the cost of treatment.

Aged↗
PubMed2001

Protein-protein interaction panel using mouse full-length cDNAs.

We have developed a novel assay system for systematic analysis of protein-protein interactions (PPIs) that is characteristic of a PCR-mediated rapid sample preparation and a high-throughput assay system based on the mammalian two-hybrid method. Using gene-specific primers, we successfully constructed the assay samples by two rounds of PCR with up to 3.6 kb from the first-round PCR fragments. In the assay system, we designed all the steps to be performed by adding only samples, reagents, and cells into 384-well assay plates using two types of semiautomatic multiple dispensers. The system enabled us examine more than 20,000 assay wells per day. We detected 145 interactions in our pilot study using 3500 samples derived from mouse full-length enriched cDNAs. Analysis of the interaction data showed both several significant interaction clusters and predicted functions of a few uncharacterized proteins. In combination with our comprehensive mouse full-length cDNA clone bank covering a large part of the whole genes, our high-throughput assay system will discover many interactions to facilitate understanding of the function of uncharacterized proteins and the molecular mechanism of crucial biological processes, and also enable completion of a rough draft of the entire PPI panel in certain cell types or tissues of mouse within a short time.

Animals↗
PubMed2001

Reduction of serum interleukin-5 levels reflect clinical improvement in patients with atopic dermatitis.

Cytokines, in particular IL-4 and IL-5, regulate IgE synthesis and eosinophil activation in atopic dermatitis (AD). To elucidate whether the serum levels of IL-4 and IL-5 are related to the serum IgE level, eosinophilia, or clinical severity of the disease, 25 cases with AD were studied. Blood samples were isolated from two groups of donors: 1) patients with AD (n = 25); 2) non-allergic individuals (NA, n = 20) with serum IgE levels below 100 IU/ml and with blood eosinophil counts below 250/microliter. Each parameter was evaluated at least twice in AD patients at the beginning of the study and after 4, 8 or 12 weeks of treatment. IL-4 was hardly detected in AD and NA, but IL-5 was increased (> 10 pg/ml) in most cases (22/25) of AD group with 513.6 pg/ml as the mean. AD with normal serum IgE levels exhibited increased levels of IL-5, whereas AD with high serum IgE levels did not necessarily have elevated IL-5 levels. The IL-5 level tended to change in parallel with the clinical severity in each AD case, although the level itself was not correlated with the clinical severity per se. A significant decrease of IL-5 was observed in AD when the clinical severity decreased. Eosinophils also decreased along with the improvement of AD, whereas the serum level of IgE did not change during the observation period. Our results suggest that IL-5 is involved in the regulation of clinical courses of AD and that its kinetics at the serum level reflects the clinical activity of AD.

Adolescent↗
PubMed2001

Successful treatment of a patient with lymphomatoid papulosis by methotrexate.

We report a case of lymphomatoid papulosis (LyP) that occurred in a 44-year-old Japanese male patient. Reddish papules with a small number of pustules and nodules were observed on the extremities, chest and upper back. Most lesions were also associated with central necrosis, ulceration and crusting, and regressed spontaneously within 4 to 6 weeks. Histopathological examination revealed wedge-shaped dense cellular infiltrate in the dermis, which was mixed with large atypical lymphoid cells, small lymphocytes, eosinophils and neutrophils. These large atypical cells expressed CD30 on their cell membrane and cytoplasm. Rearrangement of the T-cell receptor (TcR) beta-chain gene was detected in the skin lesion. Lymphadenopathy with histopathologic change similar to the skin lesions, but without TcR gene rearrangement, was found at the left inguinal area. Systemic administration of methotrexate (7.5-15.0 mg/week) was found to be dramatically effective in resolution of skin lesions and prevention of their recurrence.

Adult↗
PubMed2001

Anti-angiogenic treatment for peritoneal dissemination of pancreas adenocarcinoma: a study using TNP-470.

We established peritoneal dissemination-prone subcultures (PCI-43p3) using nude mice by a repetitive in vivo selection of intraperitoneally inoculated PCI-43, a pancreas adenocarcinoma cell line. The subcultures showed upregulated expression of matrix metalloproteinase (MMP)-9, but not MMP-2 in culture supernatants. They also produced increased amounts of vascular endothelial growth factor (VEGF), which was not associated with alterations in isoforms of VEGF mRNA. PCI-43p3 cells attached to cultured mesothelial cell monolayers more readily than did the parent PCI-43 cells. The angiogenesis inhibiting agent, TNP-470, at 30 mg / kg was administered to the model mice, resulting in a prominent suppression of the establishment of peritoneal nodules. The suppression was dependent on the duration of TNP-470 treatment. TNP-470 treatment significantly suppressed proliferation of tumor cells in disseminated nodules, assessed in terms of immunostaining for proliferating cell nuclear antigen (PCNA). TNP-470 did not affect the in vitro attachment between PCI-43p3 and mesothelial cells. The combined data show that anti-angiogenic treatment profoundly suppresses the in vivo process of peritoneal dissemination.

Adenocarcinoma↗
PubMed2001

Vaccination effect of interleukin-6-producing pancreatic cancer cells in nude mice: a model of tumor prevention and treatment in immune-compromised patients.

In an effort to explore properties important in hematogenous metastasis of pancreatic adenocarcinoma, we previously demonstrated that tumor-derived interleukin (IL)-6 is a crucial factor that conveys resistance to liver metastasis. Here we extend the study to examine a possible vaccination effect of tumor-derived IL-6 in T-cell-deficient nude mice, as a model for predicting the effect in immune-compromised patients. We used a pair of IL-6-nonproducing and highly producing pancreatic adenocarcinoma cell lines, PCI-43 and PCI-43h, respectively. The reaction intensity of anti-PCI IgG antibodies in host nude mice was maximal 28 days after inoculation of PCI-43h cells, and remained high thereafter. A fraction of the pancreatic carcinoma cell lines, namely, PCI-6, -10, and -43, expressed surface antigenic determinant(s) reactive with the IgG; but the others, PCI-19, -24, -55, -64, -66, -68, -72, and -79, did not. Inoculation of PCI-43h but not PCI-43 suppressed growth of simultaneously inoculated PCI-43, but not PCI-24 xenografts. In addition, administration of PCI-43h, but not PCI-43 suppressed the growth of PCI-43 that was xenografted 4 weeks later, thus revealing a vaccination effect of IL-6-producing PCI-43h, but not IL-6-nonproducing PCI-43. These data, obtained from T-cell-deficient nude mice, suggest an in vivo role for IL-6 in inducing IgG-mediated, pancreatic carcinoma-specific vaccination against a thymus-independent antigen.

Animals↗