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K Tsutsui

Publications and source records attributed to K Tsutsui.

At least 109 records · Page 6Linked to original sources
PubMed1996

Subdomain structure of the matrix attachment region located within the mouse immunoglobulin kappa gene intron.

Using the matrix attachment region (MAR) derived from Ig kappa gene intron, we assessed the importance of internal subregions required for the specific binding to the nuclear matrix. Relative affinities of MAR subfragments were compared in an in vitro binding reaction with isolated matrix. Cleavage at the near-centric MboII site generated two subfragments retaining a significant binding affinity. Dimerization of these subfragments greatly increased the affinity. Only a partial segment (130 bp) of the 3' fragment was necessary to restore the binding. The dimerization effect was lost when the monomer units were separated by nonMAR spacers of 500 bp <. This bipartite organization of Ig kappa MAR could be a general feature of AT-rich MARs, regardless of their genomic locations.

Animals↗
PubMed1996

Versatility of the thin groin flap.

The groin flap is one of the most usable flaps. It provides a large amount of skin coverage with an easily concealed donor site. However, when the flap is used to reconstruct areas of the neck, hand, or foot, a secondary procedure for defatting is usually necessary. Thinner flaps are thought to be more useful in these areas. We present an anatomical study of the thin groin flap, including its dissection and defatting, and 12 clinical cases using the thin groin flap for neck (n = 7), foot (n = 4), and scalp (n = 1) reconstruction. The largest successful flap measured 13 x 30 cm. Eight flaps survived completely, two had partial necrosis, and two had total necrosis. Complications were thought to be caused by dissection around the pedicle. Meticulous dissection and thinning are required to create the thin groin flap. Excellent aesthetic results requiring no secondary defatting procedures are possible with this new thin groin flap.

Adolescent↗
PubMed1996

Widespread pruritic plaques in a patient with subacute cutaneous lupus erythematosus and hypocomplementemia: response to dapsone therapy.

We describe a patient with subacute cutaneous lupus erythematosus, widespread pruritic papulosquamous plaques, and hypocomplementemia. Skin biopsy specimens revealed liquefaction degeneration and colloid bodies and dyskeratotic cells in basal and suprabasal layers. An immunofluorescence study revealed deposits of IgG, IgM, and C3 at the dermalepidermal junction in a bandlike pattern, and particulate IgG deposition in the basal and suprabasal layers. Treatment with prednisolone (15 mg/day), chloroquine phosphate (200 mg/ day), cyclosporine (5 mg/kg daily), and gold (10 mg/day) failed to reduce pruritic plaque formation, and pulse methylprednisolone therapy led to only a transient remission. Clinical exacerbations correlated with a decrease in complement levels. The disease was successfully controlled with dapsone (75 mg/day) and prednisolone (25 mg/day).

Adult↗
PubMed1996

Successful treatment of livedo vasculitis with beraprost sodium: a possible mechanism of thrombomodulin upregulation.

BACKGROUND: Livedo vasculitis is thought to be a thrombogenic disorder. We demonstrated that thrombomodulin (TM) expression on the endothelial cells in livedo vasculitis was markedly reduced, while blood tests of coagulation and fibrinolytic activities were within the normal range. OBJECTIVE: Since prostacyclin (PGI2) upregulates the TM expression of endothelial cells, we tried a PGI2 analogue for the treatment of livedo vasculitis. METHOD: Four patients with livedo vasculitis were started on a regimen of beraprost sodium (120 micrograms daily). Additional intake of low-dose aspirin was combinated with a maintenance dose of beraprost sodium (60 micrograms daily). RESULT: All 4 patients experienced a clinical improvement with a combination therapy with beraprost sodium and low-dose aspirin. CONCLUSION: We propose that PGI2 analogue therapy is useful for the treatment of livedo vasculitis, since the drug upregulates TM expression in this disorder.

Adolescent↗
PubMed1996

An oviposition-inducing peptide: isolation, localization, and function of avian galanin in the quail oviduct.

It is well established that avian oviposition is regulated, at least partly, by a neurohypophysial hormone, arginine vasotocin, and ovarian hormones, prostaglandins, are regulated through mechanisms of the induction of uterine contractions. Although abundant nerves are terminated in the musculature in the uterine and vaginal oviduct regions, limited information is available on the neuronal control mechanism of avian oviposition. To identify the oviduct factor that plays an important role in the induction of oviposition as a neurotransmitter or a neuromodulator, a study was conducted to isolate the bioactive substance involved in the vaginal and uterine contractions from mature oviducts of the Japanese quail. Acetic acid extracts of 200 quail oviducts were forced through disposable C-18 reversed-phase cartridges, and then the retained material was subjected to the reversed-phase and cation-exchange HPLC purifications. A purified bioactive substance showed a single peak on the reversed-phase HPLC and was further subjected to amino acid sequence analysis and molecular weight presumption. The substance was identified as avian galanin, which was previously isolated from chicken intestine. The synthetic peptide enhanced contractions of both the vagina and the uterus in a manner similar to the native peptide, and the threshold concentrations were 10(-9) - 10(-8) M in the vagina and 10(-10) - 10(-9) M in the uterus. An intraperitoneal injection of the synthetic peptide significantly evoked quail oviposition during 5 min after injection. Immunohistochemical analysis with the anti-galanin serum revealed that abundant immunoreactive fibers were distributed in muscle layers of the vagina and the uterus. The immunoreaction examined in these regions was completely inhibited by preincubation of the antibody with synthetic peptide. These results suggest that avian galanin in the oviduct evokes oviposition through mechanisms of the induction of uterine and vaginal contractions. This peptide may contribute as a neurotransmitter or a neuromodulator to avian oviposition.

Amino Acid Sequence↗
PubMed1996

Non-Hodgkin's lymphoma of the thyroid. A clinical study of twenty-two cases.

Non-Hodgkin's lymphoma (NHL) of the thyroid gland is a rare disease. In the present study, the survival rate and characteristics were retrospectively analyzed in 22 patients with stage IE and IIE thyroid NHL treated with radiotherapy with or without combination chemotherapy. Seventeen NHL had histological evidence of lymphoma of mucosa-associated lymphoid tissue (MALT) type. The 5-year survival rate was 85% in all patients, with 100% and 63% respectively, for stage IE and stage IIE patients. The highly significant factor correlated with decreased determinate survival was concomitant stridor.

Adult↗
PubMed1995

Isolation and characterization of opioid peptides in the avian brain.

Neuropeptides are supposed to be implicated in the regulation of hormone as well as nonhormone dependent behavioral processes in birds. Previous immunohistochemical studies have suggested that in birds opioid pentapeptides, Met- and Leu-enkephalins, may be present in the brain including the regions that regulate sex hormone dependent behaviors, such as reproductive behaviors. To determine biochemically the presence of opioid peptides in the avian brain, a study was conducted to isolate these peptides from Japanese quails and zebra finches. Acetic acid extracts of the quail and finch brains were respectively forced through disposable C-18 reversed-phase cartridges, and then the retained material was subjected to the cation-exchange and reversed-phase high performance liquid chromatographic (HPLC) purifications. All of the purified substances showed a single peak on the reversed-phase HPLC and these substances enhanced spontaneous contractions of the avian rectum. The purified bioactive substances were further subjected to amino acid sequence analysis and were characterized as peptides with the following sequences: Tyr-Gly-Gly-Phe-Met, Tyr-Gly-Gly-Phe-Leu, and Tyr-Gly-Gly-Phe-Met-Arg-Phe. These three peptides were identical with opioid pentapeptides, Met- and Leu-enkephalins, and a heptapeptide, Met-enkephalin-Arg6-Phe7, which had been previously isolated from mammalian species. This is the first direct demonstration of the presence of opioid peptides in the avian brain and confirms previous immunohistochemical findings suggesting a functional role for the opioid peptide in neural mechanisms of avian reproductive behavior.

Amino Acid Sequence↗
PubMed1995

Effects of opioid peptides on the electrical activity of preoptic and hypothalamic neurons in the quail brain.

We have recently isolated three opioid peptides, i.e., Met- and Leu-enkephalins and Met-enkephalin-Arg6-Phe7, from the avian brain. In the present study, therefore, effects of these endogenous opioid peptides on the electrical activity of preoptic and hypothalamic neurons of the adult male Japanese quail were examined using a brain slice preparation. All of the three opioid peptides inhibited the spontaneous firing activities of subsets of neurons in the preoptic area and the paraventricular nucleus in the hypothalamus. Threshold concentrations for the inhibitory action were between 10(-7) and 10(-6) M in Met- and Leu-enkephalins and approximately 10(-6) M in Met-enkephalin-Arg6-Phe7, respectively. In a few cells in these brain areas, however, Leu-enkephalin rather potentiated the spontaneous activities, resulting in an increase of firing rates or a decrease of interburst intervals. The inhibitory effect of Met-enkephalin was completely blocked by naloxone, an opioid receptor antagonist, but not affected by bicuculline, a gamma-aminobutyric acid A (GABAA) receptor antagonist. These results suggest that there are functional opiate receptors in subsets of preoptic/hypothalamic neurons and that one of their main physiological functions in these areas is an inhibition of neuronal activities. Because these brain regions are considered to be involved with the regulation of a variety of male reproductive behaviors, opioid peptides may regulate some reproductive behavior through the mechanism that provokes such an inhibition.

Action Potentials↗
PubMed1995

Developmental expression of APEX nuclease, a multifunctional DNA repair enzyme, in mouse brains.

Expression of the mammalian major apurinic/apyrimidinic (AP) endonuclease (designated as APEX nuclease, or HAP1, APE or Ref-1 gene product) during mouse brain development was investigated by in situ and northern blot hybridizations. The enzyme is known to be a redox factor (Ref-1) stimulating DNA binding activity of AP-1 binding proteins such as Fos and Jun as well as a multifunctional DNA repair enzyme having 5' AP endonuclease, DNA 3' repair diesterase, 3'-5' exonuclease and DNA 3'-phosphatase activities. In the embryonic and postnatal development, APEX mRNA was expressed at high levels in the proliferative zone of various brain regions, with showing temporal and spatial changes. Its expression decreased in association with brain development to the basal expression level which was observed even in adulthood, with the exception of its expression in the hippocampal formation. The growth-dependent expression of APEX gene suggests that it has some roles on cell proliferation and/or differentiation in developmental brain. Its expression on the hippocampal formation became significant from postnatal day 7 and then increased. The pyramidal and granule cell layers expressed it at a higher level than most other brain regions at postnatal day 21. The developmental change of APEX gene expression was not necessarily associated with the changes of expression of c-fos and c-jun genes measured by northern blot hybridization. However, the present results suggested that APEX/Ref-1 gene product can interact with AP-1 binding proteins in brain, especially in the hippocampal formation, to regulate some brain functions by redox-activation.

Aging↗
PubMed1995

Avian neurosteroids. I. Pregnenolone biosynthesis in the quail brain.

The present study was carried out to determine steroid biosynthesis from cholesterol in the brain of adult male Japanese quails. As an initial step of the experiments, the concentrations of pregnenolone, dehydroepiandrosterone and their sulfate esters in the brain and plasma extracts were measured by specific radioimmunoassays (RIAs). To exclude the possibility that these steroids in the brain are derived from peripheral steroidogenic glands, hypophysectomized and sham-operated birds were used in this experiment. The pregnenolone concentration was much larger in the brain than in the plasma in these two groups. Hypophysectomy led to decreases in the plasma and brain pregnenolone concentrations, but the change in the brain was less pronounced than that in the plasma. Although pregnenolone sulfate ester, dehydroepiandrosterone and its sulfate ester were also detected in brain extracts, those levels were low in both hypophysectomized and sham-operated birds. The biochemical demonstration of cholesterol metabolism was further conducted in intact mitochondria. When mitochondrial fractions obtained from the whole brain were incubated with cholesterol at 37 degrees C, the pregnenolone level in mitochondria increased as a function of incubation time. Finally, Western immunoblot analysis using a purified IgG with polyclonal antibodies against the purified bovine adrenal cytochrome P450scc was performed after SDS-gel electrophoresis of homogenates of the hypothalamus and preoptic area. A protein recognized the antibody as a band of electrophoretic mobility in the proximity of reference bovine P450scc. These results suggest that the brain produces pregnenolone from cholesterol in adult male Japanese quails. Most accumulation of pregnenolone in the brain may be independent of the peripheral endocrine gland system.

Animals↗
PubMed1995

Avian neurosteroids. II. Localization of a cytochrome P450scc-like substance in the quail brain.

We have recently demonstrated that the avian brain as well as the peripheral steroidogenic glands produces pregnenolone, the main precursor of steroid hormones, on the basis of biochemical studies. Therefore, the immunohistochemical and Western immunoblotting analyses with a polyclonal antibody directed against the purified bovine adrenal cytochrome P450scc, which is involved in pregnenolone formation, was undertaken to investigate the localization of a cytochrome P450scc-like substance in the brain of adult male Japanese quails. P450scc-like immunoreactive cells were distributed in several telencephalic, diencephalic and mesencephalic regions. An intense immunoreaction was observed in somata of Purkinje cells and in the dendrites extending through the cerebellar molecular layer. Clusters of immunoreactive cell bodies were also detected in the hyperstriatum accessorium (HA), the ventral portions of both the archistriatum and the corticoid area, the preoptic area (POA), the anterior hypothalamus (AHy) and the dorsolateral thalamus (DL). Preadsorbing the antibody with cytochrome P450scc resulted in a complete absence of P450scc-like immunoreactivity in all of positively stained cells. On Western immunoblotting with the P450scc antibody, a P450scc-like substance was present in homogenates of the several brain regions that contain immunohistochemically stained cells. Immunohistochemical experiments using both antibodies against P450scc and the glial fibrillary acidic protein (GFA), a specific marker of glial cells, indicated that many HA cells contained both P450scc-like and GFA-like immunoreactivities. However, no immunoreactivity for GFA was observed in Purkinje cells and the cells localized in the ventral portion of the corticoid area, despite the presence of P450scc-like immunoreactivity. These results confirm our previous findings of pregnenolone biosynthesis and suggest the presence of a P450scc-like substance in both neuronal and glial cells of the quail brain.

Animals↗
PubMed1995

Cloning, sequence analysis, and chromosomal assignment of the mouse Apex gene.

APEX nuclease (Apex gene product) is a mammalian multifunctional DNA repair enzyme possibly involved in the repair of apurinic/apyrimidinic (AP) sites and single-strand DNA breaks with 3' termini blocked by nucleotide fragments and also in transcriptional regulation via redox activation of the AP-1 transcription factors. We cloned a 15-kb DNA fragment containing the Apex gene from a mouse leukocyte genomic library and determined a 4-kb stretch of its nucleotide sequence, including the complete sequence of the mouse Apex gene. The gene consists of 5 exons and 4 introns spanning 2.21 kb, and the boundaries between exons and introns follow the GT/AG rule. Two major and one minor transcription initiation sites were assigned to positions +1 and +24 and position +14, respectively, by a combination of ribonuclease protection, primer extension, and 5' RACE analyses. Position +1 is located 312 nucleotides upstream from the ATG initiation codon. The translation initiation and termination sites are located in exon II and exon V, respectively. The sequenced 5' flanking region (1.32 kb) lacks a typical TATA box, but contains a CAAT box and putative binding sites for several transcription factors, such as ATF, NF-IL6, Sp1, and AP2. The 0.8-kb region from position -410 (5' flanking region) to position +386 (intron II) contains a CpG island. The Apex gene locus was mapped to mouse chromosome 14C2-D1 using in situ hybridization.

Animals↗
PubMed1995

Phylogenetic analysis of phospholipase C genes from Clostridium perfringens types A to E and Clostridium novyi.

The phylogenetic interrelationships between strains of 5 toxin types (A to E) of Clostridium perfringens were examined by analysis of differences in the nucleotide sequences of phospholipase C genes (plc genes) among 10 strains, including 3 strains for which the plc gene sequences have been previously reported. A plc gene was also cloned from a Clostridium novyi type A strain and sequenced to analyze the interspecies diversity of plc genes. Phylogenetic trees constructed by the neighbor-joining method revealed that the phylogeny of C. perfringens strains is not related to toxin typing, in agreement with the results of a comparative genome mapping study by Canard et al. (B. Canard, B. Saint-Joanis, and S. T. Cole, Mol. Microbiol. 6:1421-1429, 1992). Various C. perfringens phospholipase C enzymes were purified from cultures of Escherichia coli cells into which the encoding plc genes had been cloned. All of the enzymes showed the same specific activity. On the other hand, the level of plc transcripts differed greatly (up to 40-fold) from one C. perfringens strain to another. No significant difference in the nucleotide sequence of the plc promoter region was observed for any of the plc genes. These results suggest that the variation in phospholipase C activity among different strains is not due to mutation in the plc coding region but to that in an extragenic region. The evolution of C. perfringens phospholipase C is discussed on the basis of similarities and differences between clostridial plc genes.

Amino Acid Sequence↗
PubMed1995

User interface design and evaluation for electronic medical record system.

A user interface for an electronic medical record system (EMRS) is proposed. A pen-based device adopted for data input and the GUI windows layout simulate conventional paper forms, so that doctors can quickly grow accustomed to the EMRS. A comparison study shows the proposed interface does not significantly delay the examination, even when used in hospitals with many outpatients.

Ambulatory Care↗
PubMed1994

Esophageal cancer treated with radiotherapy: impact of total treatment time and fractionation.

PURPOSE: Local control rate and survival rate of esophageal cancer treated with radical radiation therapy (RT) were analyzed with special respect to total treatment time and fractionation. METHODS AND MATERIALS: Between 1979 and 1992, 88 patients with Stages I-III esophageal cancer were treated radically with RT at Kyoto University Hospital and Wakayama Red Cross Hospital. Of the 88 patients, 52 patients were treated with conventional fractionation (1.7-2.0 Gy/day, five times/week), and the remaining 36 patients were treated with accelerated hyperfractionation (AHF). In 1989, we started AHF regimen for esophageal cancer. Daily fractionations were 2.0 Gy and 1.2 Gy (field-in-field), or 1.5 Gy and 1.5 Gy at 5- to 6-h interval. Most of the patients treated with AHF received the total radiation dose of 64-68 Gy. Twenty-seven patients were treated with intraluminal brachytherapy (IBT) as boost therapy following external RT. Fourteen patients were treated with IBT following AHF. RESULTS: The median of treatment time of AHF was approximately 2 weeks shorter than that of conventional fractionation. Local control rate at 1 year were 47% for AHF, which was significantly higher than that for conventional fractionation (22%, p < 0.05). The improvement of local control by AHF was responsible for a trend to an improved cause-specific survival (p = 0.07). Local control rates at 1 year were plotted as a function of total treatment time. The slope of the linear regression line was -2.3 +/- 0.5% per day (p < 0.025) for patients treated with external RT alone, indicating a 2.3% per day loss in local control. Pretreatment and treatment parameters were evaluated in a multivariate analysis for the end point of local control. T stage (T1, 2 vs. T3, 4; p = 0.003) and fractionation schedule (p = 0.03) were independent of prognostic significance. Patients could tolerate the AHF well, although esophageal stenosis was noted frequently as a late toxicity. CONCLUSION: Accelerated hyperfractionation was the most important treatment-related variable in this patient population. Total treatment time may have a significant impact on the treatment outcome for esophageal cancer.

Adenocarcinoma↗
PubMed1994

Three-dimensional treatment planning for maxillary cancer using a CT simulator.

PURPOSE: The results of three-dimensional treatment planning using a computed tomography simulator were evaluated in patients with maxillary cancer. METHODS AND MATERIALS: Treatment planning was done in 25 patients using an x-ray simulator and plain x-ray films (1979-1982, group 1) in 34 patients using an x-ray simulator and computed tomography films (1983-1987, group 2), in 24 patients using a computed tomography simulator (1988-1992, group 3). The number of patients with Stage IV disease increased in the order of group 1 to group 3. RESULTS: The average radiation field was smallest in group 3 (66.5 cm2) followed by group 2 (67.4 cm2) and group 1 (72.9 cm2). A radiation dose of more than 30 Gy to the lens of the effected side was delivered to 13% of group 3, 44% of group 2, and 44% of group 1. The dose to the lens on the uneffected side was zero in 56% of group 1, 74% of group 2, and 96% of group 3. A long-term decrease in visual activity on the effected side occurred in 11% of group 3, 32% of group 2, and 44% of group 1. However, a significant increase in survival was only noted between groups 1 and 2, because the three population of patients were different. CONCLUSION: The three-dimensional treatment planning results in a better treatment than two-dimensional treatment planning as measured by complication rates and field sizes.

Aged↗