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S Kojima

Publications and source records attributed to S Kojima.

At least 253 records · Page 14Linked to original sources
PubMed1998

Neuroanatomical correlates of the assessment of facial attractiveness.

Frontal cortical damage can lead to changes in affective aspects of personality. However, the difficulty of dissociating such abnormalities from cognitive disorders has overshadowed most previous findings. Regional cerebral blood flow (rCBF) was measured with positron emission tomography (PET) while normal subjects were assessing facial attractiveness. Two left frontal regions showed a significant increase in rCBF while assessing facial attractiveness. The increased rCBF in the left anterior frontal cortex correlated with the overall percentage of assessments of a face as unattractive, while that in the left fronto-temporal junction correlated with the percentage of assessments of a face as attractive. These findings provide direct evidence that the left frontal regions are engaged in the assessment of facial attractiveness.

Adult↗
PubMed1998

Detection of bcr/abl fusion transcripts by semiquantitative multiplex RT-PCR combined with a colormetric assay in Ph positive leukemia.

We studied the feasibility of the clinical application of a new bcr/abl analysis system, C-TRAK t(9;22), consisting of a multiplex RT-PCR and a colormetric assay. With this system, bcr/abl transcripts could be detected in all of 24 cytogenetic Philadelphia chromosome (Ph) positive leukemia patients and in none of eight Ph negative patients. Multiple bcr/abl transcripts could be detected in three of the 24 Ph positive patients, the fusion of bcr exon 1 to abl exon 2 (e1a2 junction) dominated that of bcr exon 13 to abl exon 2 (b2a2 junction) in two cases and that of bcr exon 14 to abl exon 2 (b3a2 junction) and b2a2 dominated e1a2 in one case. This system was sensitive enough to be able to detect even one bcr/abl transcript-producing cell in 50000 bcr/abl negative background cells, thus making it suitable for semiquantitative evaluation. Minimal residual disease (MRD) was monitored in one Ph positive leukemia patient who underwent allogenic bone marrow transplantation (allo-BMT). After allo-BMT, a weak positivity of the bcr/abl transcript continued with no clinical relapse; this result was consistent with that of a conventional nested PCR assay using ethidium bromide staining. Including all the procedures for RNA extraction, it took only about 10 h to detect the bcr/abl transcripts. Our findings indicate that this bcr/abl analysis system provides a quick and sensitive method for screening bcr/abl transcripts and possibly for monitoring MRD in Ph positive leukemia patients.

Acute Disease↗
PubMed1998

Solution structure of Der f 2, the major mite allergen for atopic diseases.

House dust mites cause heavy atopic diseases such as asthma and dermatitis. Among allergens from Dermatophagoides farinae, Der f 2 shows the highest positive rate for atopic patients, but its biological function in mites has been perfectly unknown, as well as the functions of its homologs in human and other animals. We have determined the tertiary structure of Der f 2 by multidimensional nuclear magnetic resonance spectroscopy. Der f 2 was found to be a single-domain protein of immunoglobulin fold, and its structure was the most similar to those of the two regulatory domains of transglutaminase. This fact, binding to the bacterial surface, and other small pieces of information hinted that Der f 2 is related to the innate antibacterial defense system in mites. The immunoglobulin E epitopes are also discussed on the basis of the tertiary structure.

Allergens↗
PubMed1998

Retinoids potentiate transforming growth factor-beta activity in bovine endothelial cells through up-regulating the expression of transforming growth factor-beta receptors.

Retinoic acid (RA) induces the activation of latent transforming growth factor-beta (TGF-beta) in bovine aortic endothelial cells (BAECs) via enhancement of cellular plasminogen activator (PA)/plasmin levels. The resultant TGF-beta suppresses the excessive fibrinolytic activity by decreasing PA expression and stimulating expression of the PA inhibitor, PA inhibitor-1 (PAI-1), and inhibits cell proliferation. Here, we report that, in this regulatory system, RA simultaneously up-regulates the expression of TGF-beta receptor types I and II, resulting in enhancement of TGF-beta activity in the cells. RA increased the numbers of high- and low-affinity binding sites for 125I-TGF-beta1 2.1-fold and 1.5-fold, respectively, without alteration of their Kd values. Affinity labeling and Western and Northern blotting studies showed that, following RA treatment, surface levels of both type I and type II receptors increased due to augmentation in their mRNA levels. The effect was dose- and time-dependent. Treatment with 1 microM RA for 15 hr increased mRNA levels of type I and II receptor threefold and eightfold, respectively. Pretreatment of BAECs with either RA or retinol lowered the concentration of TGF-beta1 required to suppress PA levels, to enhance PAI-1 levels, and to inhibit cell proliferation. Thus, retinoids may regulate cellular functions of BAECs not only by inducing the formation of active TGF-beta but also by stimulating TGF-beta receptor expression. This regulatory mechanism may sustain TGF-beta-mediated regulation of EC function at a focal site where RA is acting.

Actins↗
PubMed1998

Stimulatory effects of neopterin on hematopoiesis in vitro are mediated by activation of stromal cell function.

The pteridine neopterin (NP) was shown to be produced by monocytes and is known to be a useful marker of immunological activation, although, its biological activity is still unclear. Recently, we found that intravenous administration of NP increased the numbers of blood leukocytes, and granulocyte-macrophage progenitor cells (CFU-GM) in the bone marrow and spleens of mice. In order to elucidate the mechanism whereby NP stimulates hematopoiesis, the effects of NP on hematopoietic stem cell proliferation and differentiation in vitro were studied using a long-term bone marrow culture (LTMC) system with cloned stromal cell line, MS-5. Adding NP to the LTMC increased the numbers of cells in total, CFU-GM and colony-forming unit in spleen (CFU-S). NP also increased the number of CFU-GM in a soft agar culture system, but it did not enhance CFU-GM colony formation when target bone marrow cells were semi-purified (T, B and adherent cell-depleted bone marrow cells) and cultured in this system, suggesting that NP did not directly affect the proliferation of hematopoietic progenitors. Conditioned medium obtained from NP-treated stromal cells had much greater colony-stimulating activity than that obtained from untreated stromal cells. Furthermore, NP treatment stimulated the production of IL-6 and GM-CSF by stromal cells. All these findings suggest that NP stimulates hematopoietic cell proliferation and differentiation in vitro by activating stromal cell function.

Animals↗
PubMed1998

Acute myocardial infarction with simultaneous occlusions of two major coronary arteries in a young man.

Simultaneous formation of the thrombi in two different coronary arteries is a very rare event. We present a 34-year-old man with acute myocardial infarction due to simultaneous occlusion of the two major coronary arteries. His only risk factor was smoking 40 cigarettes daily. Emergency arteriography revealed a total occlusion of the proximal left anterior descending artery (LAD) and the left circumflex coronary artery (LCx). We performed primary angioplasty to the LAD and instituted thrombolytic therapy to the LCx. During intra-aortic balloon pumping and medical treatment, the patient had no symptoms of angina. He underwent a second catheterization 4 weeks after primary angioplasty. After intravenous ergonovine provocation, coronary arteriography revealed diffuse vasospasm of the LAD and the LCx. These data suggest that habitual heavy smoking and coronary spasm may have been causatory factors for myocardial infarction in this case.

Adult↗
PubMed1998

Paraphyletic status of Polychaeta suggested by phylogenetic analysis based on the amino acid sequences of elongation factor-1 alpha.

In order to judge whether or not Polychaeta is a paraphyletic group, I determined almost the entire amino acid sequence of elongation factor-1 alpha from thirteen polychaetes, two oligochaetes, two hirudineans, two vestimentiferans, and two molluscs. Phylogenetic analysis by the neighbor-joining (NJ) method and the maximum likelihood (ML) method indicated the monophyly of Clitellata (the oligochaetes and hirudineans). In both the NJ and ML trees, vestimentiferans and clitellates were derived from polychaetes independently. The present results strongly suggest that Polychaeta is a paraphyletic group.

Amino Acid Sequence↗
PubMed1998

Echocardiography of a right atrial mass in hepatocellular carcinoma.

Antemortem diagnosis of hepatocellular carcinoma with a tumor thrombus extending into the right atrium has been rarely observed. Although echocardiography allows easy detection of the intracardiac mass, reports of echocardiographic descriptions of a right atrial mass associated with hepatocellular carcinoma are few. Herein, we describe two cases of hepatocellular carcinoma with a tumor thrombus in the right atrium detected by transthoracic echocardiography. In one of the patients we also performed transesophageal echocardiography. Neither patient had cardiac symptoms or signs. Thus, echocardiographic examination is very important in patients with hepatocellular carcinoma, with or without cardiac symptoms and signs.

Aged↗
PubMed1998

Contrast-enhanced endoscopic ultrasonography in gallbladder diseases.

BACKGROUND: The purpose of this study was to investigate the usefulness of contrast-enhanced endoscopic ultrasonography in gallbladder diseases. METHODS: Subjects were 38 patients including 12 with adenocarcinoma, 2 adenosquamous carcinoma, 6 cholesterol polyp, 10 cholecystitis, and 8 adenomyomatosis. After endoscopic ultrasonography, sonicated albumin was intravenously injected and the enhanced effect on images of these lesions was determined. For malignancies we compared diagnostic accuracy (T factor, TNM classification) of endoscopic ultrasonography and contrast-enhanced endoscopic ultrasonography. Vascularity as shown by contrast-enhanced endoscopic ultrasonography and angiograms was compared. RESULTS: Enhancement was observed in 11 patients with adenocarcinoma but not of those with adenosquamous carcinoma or cholesterol polyp. Angiography provided hypervascular images for all cases of adenocarcinoma, but all other lesions were hypovascular. In one case of adenocarcinoma, 3 cases of adenomyomatosis, and 8 cases of cholecystitis, there was a discrepancy between contrast-enhanced endoscopic ultrasonography images and angiograms with regard to vascularity. The accuracy of depth of tumor invasion for endoscopic ultrasonography was 78.6% (11 of 14) versus 92.9% (13 of 14) for contrast-enhanced endoscopic ultrasonography. CONCLUSION: Contrast-enhanced endoscopic ultrasonography is useful in the diagnosis of gallbladder lesions.

Adenocarcinoma↗
PubMed1998

Histochemical study on the relation between NO-generative neurons and central circuitry for feeding in the pond snail, Lymnaea stagnalis.

To examine whether nitric oxide (NO)-generative neurons are included in the central circuitry for generation of feeding pattern in the pond snail, Lymnaea stagnalis, two staining techniques for NADPH diaphorase and serotonin (5-HT) were applied for its central nervous system (CNS). The former technique is known to show localization of NO synthase; the latter is well employed as a marker for the feeding circuitry because 5-HT is a main transmitter in it. In the buccal ganglion, B2 motoneuron was found to be a putative NO-generative neuron. This motoneuron is not involved directly in the coordination of feeding pattern but is activated simultaneously with the feeding to control the oesophageal and gut tissues for the digestion. Taking account of the diffusion effects of NO, the NO released from B2 motoneuron, when the feeding is started, is thought to sufficiently modulate the feeding circuitry. In the cerebral ganglion, the superior lip nerve, the median lip nerve and the tentacle nerve included both putative NO-generative fibers and serotonergic fibers. These fibers are not identical, but the NO released in the nerves may activate the serotonergic fibers, resulting in the influence upon the initiation of the feeding. Therefore, our present findings clearly showed that NO is not involved in transmission within the central circuitry for the feeding, but suggested that NO can crucially affect the feeding behavior, such as initiation and modulation of the feeding pattern.

Animals↗
PubMed1998

Acute renal failure in accidental hypothermia of cold water immersion.

We report a 27-year-old Japanese man who developed acute renal failure associated with cold water immersion. The clinical course was consistent with that of acute renal failure attributable to acute tubular necrosis. A renal biopsy specimen showed patchy and focal loss of tubule cells, necrotic epithelium, interstitial edema, and arterial lumina obstructed by diffuse and severe intimal thickening. Endothelin increased more than five times in the early phase of the clinical course. Vasoconstriction and ischemia induced by cold exposure seem to lead to endothelin release. Endothelin may be related to the development of acute renal failure and intimal thickening.

Accidents↗
PubMed1998

Sensory impairments in spinal multiple sclerosis: a combined clinical, magnetic resonance imaging and somatosensory evoked potential study.

Thirty-one cases (26 patients) of clinically definite multiple sclerosis with predominant spinal cord involvement were studied retrospectively, focusing in particular on the results of sensory testings which were compared with the findings of spinal cord magnetic resonance imaging (MRI) and somatosensory evoked potentials (SEPs). Factor analysis of the sensory impairments showed two factors corresponding to superficial (pain and light-touch) and deep (position and 'thumb/big toe localizing') sensations. Vibratory sense depended on both factors, but more on deep sensations. Multiple regression analysis of the SEP abnormalities and sensory deficits showed that impaired deep sensations contributed to abnormal SEPs, but the results of clinical sensory testings and SEPs were dissociated in 31% of the extremities examined. The MRI sagittal images correlated well with the levels of sensory impairments, whereas the axial images showed a poor relationship to the extent of sensory impairments. We concluded that the use of SEPs as well as MRI is not always superior to such clinical sensory tests as the 'thumb/big toe localizing tests'.

Adolescent↗
PubMed1998

Effect of high molecular mobility of poly(vinyl alcohol) on protein stability of lyophilized gamma-globulin formulations.

The protein stability of lyophilized serum gamma-globulin (BGG) formulations containing poly(vinyl alcohol) (PVA) and dextran was studied in relation to the molecular mobility as determined by proton NMR. The critical temperature, Tmc, at which the Lorentzian relaxation process due to liquid polymer protons appears in these lyophilized formulations was lower than the glass transition temperature, Tg. Above Tmc, protein aggregation in the formulations was related to the Tmc according to the Williams-Landel-Ferry equation by replacing Tg with Tmc. Protein aggregation appears to occur substantially in a "rubbery-like" state even below Tg, if the formulations become microscopically liquidized above Tmc. Lyophilized BGG formulations containing PVA with a lower water content were less stable than those containing dextran with a higher water content. The difference in stability can be explained by the difference in the Tmc of these formulations. Tmc that is determined by NMR relaxation measurement appears to be a useful parameter for the characterization of protein formulations, for which the Tg cannot generally be determined by standard calorimetric techniques. Furthermore, Tmc appears to be more closely related to protein stability than does Tg.

Calorimetry, Differential Scanning↗
PubMed1998

Hemolytic uremic syndrome after allogeneic or autologous hematopoietic stem cell transplantation for childhood malignancies.

Of 193 children who underwent hematopoietic stem cell transplantation (HSCT) for various malignancies, 10 developed hemolytic uremic syndrome (HUS) 1 1/2-5 months later. All 10 had microangiopathic hemolytic anemia, thrombocytopenia and impaired renal function. Six of 10 presented with pericardial effusion, while three presented with hypertension. No child required plasma exchange, and all patients have survived without life-threatening long-term sequelae. By univariate analysis, the underlying diagnosis of neuroblastoma and a history of cisplatin (CDDP) administration were significantly associated with the development of HUS (P < 0.0001). By multivariate analysis using logistic regression, neuroblastoma and use of total body irradiation (TBI) as a conditioning regimen were significant contributing factors for HUS (P = 0.0001 and 0.036, respectively). Although CDDP administration could not be evaluated because of its strong correlation with the underlying diagnosis, we speculate that CDDP may enhance the nephrotoxicity of TBI, leading to a high incidence of HUS in patients with neuroblastoma.

Adolescent↗
PubMed1998

Treatment of MPS VII (Sly disease) by allogeneic BMT in a female with homozygous A619V mutation.

A 12-year-old girl with Sly disease (mucopolysaccharidosis VII; beta-glucuronidase deficiency), who is homozygous for the A619V mutation, had a successful allogeneic BMT, donored by an HLA-identical unrelated female to replace the deficient enzyme. Within 5 months after BMT, the enzyme activity of the recipient's lymphocytes increased to normal range. No signs of acute or chronic GVHD were observed. For the successive 31 months post-BMT, beta-glucuronidase activity in her lymphocytes was maintained at almost normal levels and excretion of glycosaminoglycans in the urine was greatly diminished. Ultrastructural findings demonstrated no abnormal vacuoles and inclusion bodies in the cytoplasm of her rectal mucosal cells. Coincident with the restoration of the enzyme activity, clinical improvement was dramatic. Especially notable were improvements in motor function. The patient was able to walk alone for a long time without aid, and she even became able to ride a bicycle and take a bath. In addition, recurrent infections of the upper respiratory tract and the middle ears decreased in frequency and severity, and dyspnea on exertion, severe snoring and vertigo have substantially improved. Thus, allogeneic BMT in this patient produced a better quality of life and provided a more promising outlook.

Bone Marrow Transplantation↗
PubMed1998

Allogeneic bone marrow transplantation for childhood leukemia following a busulfan and melphalan preparative regimen.

Thirty children with leukemia underwent allogeneic bone marrow transplantation (BMT) following a radiation-free preparative regimen, from July 1988 to January 1996. Twelve males and 18 females, ages 9 months to 15 years (median 8.5 years), received busulfan (BU, 4 mg/kg/day for 4 days by mouth), followed by melphalan (L-PAM, 60-70 mg/m2/day i.v. for 3 days), and infusion of allogeneic marrow from an HLA-matched related donor. Diagnoses included acute myelogenous leukemia (n = 20), acute lymphoblastic leukemia (n = 8) and chronic myelogenous leukemia (n = 2). Twenty-five patients were transplanted in first complete remission (CR), three in second CR, and two patients with chronic myelogenous leukemia in the first chronic phase. Graft-versus-host disease (GVHD) prophylaxis consisted of methotrexate (MTX) alone in 27 patients and short-term MTX and cyclosporin A in three patients. Engraftment was achieved in all patients. Toxicities were mild or moderate. Six patients developed acute GVHD: four had grade I and two had grade II. Chronic GVHD was documented in eight patients. Three patients relapsed. As of September 1997, 27 patients were alive and well at 22-110 months (median 61) of follow-up. The disease-free survival rate at 5 years after BMT was 90%. A regimen consisting of high-dose BU and L-PAM without total body irradiation is useful for conditioning for allogeneic BMT in children with leukemia.

Adolescent↗
PubMed1998

Late-onset hemorrhagic cystitis after hematopoietic stem cell transplantation in children.

We analyzed the incidence, complications, and risk factors for late-onset hemorrhagic cystitis (HC) in 256 children undergoing hematopoietic stem cell transplantation (HSCT). Twenty-six recipients (10.2%) developed late-onset HC between 3 and 270 days (median, 33 days) after HSCT. In most patients, the severity of HC was mild to moderate, and spontaneous resolution occurred. Three children developed bladder tamponade, and one required suprapubic cystotomy. Four children died in the early post-transplant period without resolution of HC, but HC was not the direct cause of death in any patient. Twenty-two patients recovered within 6-86 days (median, 16 days) of onset. Three predisposing factors were identified for development of late-onset HC by multivariate analysis: allogeneic HSCT, older age (> or = 7 years), and busulphan for pretransplant conditioning were significantly associated with late-onset HC (P=0.022, P=0.044 and P=0.036, respectively). Excretion of adenovirus type 11 was demonstrated in six of 22 patients at the onset of cystitis. We suspect that reactivation of virus may be a major pathogenic factor in late-onset HC, but several clinical factors are also associated.

Adolescent↗