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S Wada

Publications and source records attributed to S Wada.

At least 235 records · Page 13Linked to original sources
PubMed1996

[Progress and clinical usefulness of color Doppler method in diagnosing abdominal diseases].

We report the clinical usefulness of extracorporeal color Doppler ultrasonography (CDUS), color Doppler endoscopic ultrasonography (CDEUS), and recent progress in diagnosing abdominal diseases by the color Doppler method. CDUS has the advantage of being able to be performed repeatedly and noninvasively, it is thought to be useful for the evaluation of tumor vascularity and diagnosis of vascular tumor invasion and analysis of hemodynamics in abnormal vessels found in several abdominal diseases. CDEUS, which is performed under endoscopic ultrasonography (EUS), can evaluate the hemodynamics more minutely and visualize small vessels more clearly than conventional CDUS. Recent progress in the color Doppler method, such as US color angiography and the use of contrast agents is expected to lead to a higher resolution of visualization and easier detection of abdominal vessels.

Abdomen↗
PubMed1996

Involvement of gicerin, a cell adhesion molecule, in tracheal development and regeneration.

Gicerin is a novel cell adhesion protein that belongs to the immunoglobulin superfamily. Gicerin protein adheres to neurite outgrowth factor, an extracellular matrix protein in the laminin family, and also exhibits homophilic adhesion. In the present study, we investigated the involvement of gicerin and neurite outgrowth factor in tracheal development and regeneration. In an early embryonic stage, gicerin protein was highly expressed in tracheal epithelial cells, but not in loosely arranged mesenchymal cells. During development, mesenchymal cells become condensed around the tracheal epithelium and then differentiate into muscle and cartilage; high levels of gicerin expression were observed in these cells. In the later embryonic and posthatching stages, no gicerin expression was detected in tracheal epithelium or cartilage. In addition, expression of gicerin increased transiently in the tracheal epithelium during the regeneration after tracheitis induced by the infectious bronchitis virus. Furthermore, a polyclonal antibody against gicerin inhibited the epithelial regeneration in tracheal organ cultures. These findings suggest that glcerin plays an important role in both tracheal development and regeneration.

Animals↗
PubMed1995

Effects of night work on the cognitive function in young and elderly subjects with specific reference to the auditory P300.

To estimate the effects of night work on the human cognitive function, P300 event related potentials (ERPs) evoked with an auditory "oddball" paradigm were recorded for 17 nurses (mean age 27.4 +/- 6.1 years; range 21-41 years) for 3 epochs; after a night of work, after a day of work and on a holiday, and for 12 elderly security guards (mean age 62.8 +/- 2.2 years; range 60-67 years) for 2 epochs; after a night of work and on a holiday. The Stress Arousal Check List (SACL) was used for all the subjects just prior to the P300 ERP recording to determine the extent of stress and the arousal grades. Fourteen of the nurses were in their twenties (mean age 24.9 +/- 2.6 years; range 21-29 years), and 3 (39.0 +/- 2.6) were older (36, 40 and 41 years). The 14 nurses were classed as the young group. All the security guards were classed as the elderly group. In the young group, the stress grade scores increased significantly (P < 0.05) and the arousal grades decreased significantly (P < 0.01) after night work as compared to the holiday values. Although statistically not significant, the amplitude of the P300 component tended to decrease after night work, whereas the latency was very stable for these 2 epochs. The P300 latencies of the 3 older nurses were as stable as those of the young group, but their amplitudes were significantly reduced after night work as compared with the holiday amplitudes (P < 0.05). In contrast, the 12 elderly security guards showed no statistically significant changes in the scores for the stress and arousal grades between the 2 epochs, after night work and holiday. Latency prolongation however, was statistically significant (P < 0.01) after night work. The P300 amplitudes for many of the elderly security guards also tended to decrease after night work, but were not statistically significant. The P300 amplitude is considered to reflect the amount of attentional resources and the latency to reflect the time needed for the cognitive process, indicating that the elderly security guards experiences slowing of the cognitive process in night work. Our results suggest that the effect of night work on the cognitive function is greater for elderly than for young workers. We conclude that P300 can be used to evaluate changes in the human cognitive function produced by night or rotating shift work and that the results provide useful information with which to plan shift schedules on the basis of worker age.

Adult↗
PubMed1995

Interleukin (IL)-6 induction of osteoclast differentiation depends on IL-6 receptors expressed on osteoblastic cells but not on osteoclast progenitors.

We reported that interleukin (IL) 6 alone cannot induce osteoclast formation in cocultures of mouse bone marrow and osteoblastic cells, but soluble IL-6 receptor (IL-6R) strikingly triggered osteoclast formation induced by IL-6. In this study, we examined the mechanism of osteoclast formation by IL-6 and related cytokines through the interaction between osteoblastic cells and osteoclast progenitors. When dexamethasone was added to the cocultures, IL-6 could stimulate osteoclast formation without the help of soluble IL-6R. Osteoblastic cells expressed a very low level of IL-6R mRNA, whereas fresh mouse spleen and bone marrow cells, both of which are considered to be osteoclast progenitors, constitutively expressed relatively high levels of IL-6R mRNA. Treatment of osteoblastic cells with dexamethasone induced a marked increase in the expression of IL-6R mRNA. By immunoblotting with antiphosphotyrosine antibody, IL-6 did not tyrosine-phosphorylate a protein with a molecular mass of 130 kD in osteoblastic cells but did so in dexamethasone-pretreated osteoblastic cells. Osteoblastic cells from transgenic mice constitutively expressing human IL-6R could support osteoclast development in the presence of human IL-6 alone in cocultures with normal spleen cells. In contrast, osteoclast progenitors in spleen cells from transgenic mice overexpressing human IL-6R were not able to differentiate into osteoclasts in response to IL-6 in cocultures with normal osteoblastic cells. These results clearly indicate that the ability of IL-6 to induce osteoclast differentiation depends on signal transduction mediated by IL-6R expressed on osteoblastic cells but not on osteoclast progenitors.

Animals↗
PubMed1995

Expression and phosphorylation of rat c-met/hepatocyte growth factor receptor during rat liver regeneration.

Hepatocyte growth factor receptor is identified as a heterodimeric tyrosine kinase encoded by the c-met gene. This study was designed to determine how the c-met/hepatocyte growth factor receptor participates in the intracellular events involved in rat liver regeneration induced by administration of carbon tetrachloride. Expression of the rat c-met mRNA increased, peaking 24 h after carbon tetrachloride administration almost in parallel with MET protein expression. Histochemical studies demonstrated that expression of the rat c-met was enhanced in cells surrounding the damaged areas, and also that the distribution of cells expressing MET was almost in accordance with that of cells expressing proliferating cells nuclear antigen. The MET protein underwent intense tyrosine phosphorylation peaking at 12 h after carbon tetrachloride administration, and prior to DNA synthesis. Phospholipase C gamma and phosphatidylinositol 3-kinase, intracellular signal transducing molecules containing Src homology 2 domain, were associated with the MET protein following tyrosine phosphorylation in vivo. These observations suggest that expression and tyrosine phosphorylation of MET protein associated with signal transducing molecules may provide a mechanism whereby hepatocyte growth factor exerts its action on hepatocyte growth during rat liver regeneration induced by carbon tetrachloride administration.

Animals↗
PubMed1995

Spatially and temporally regulated expression of the LIM class homeobox gene Hrlim suggests multiple distinct functions in development of the ascidian, Halocynthia roretzi.

Hrlim is a LIM class homeobox gene that was first isolated from the ascidian Halocynthia roretzi. To assess its roles in early development of the ascidian, spatial and temporal expression of Hrlim was examined by whole mount in situ hybridization. This revealed that transcription of Hrlim is activated at the 32-cell stage specifically in the endoderm lineage. Hrlim is also transiently expressed in all notochord precursor cells. Expression in the endoderm lineage continues through to the middle of gastrulation. After gastrulation, Hrlim is expressed in certain lineages that give rise to subsets of cells in the brain and spinal cord. Based on these observations, it is suggested that Hrlim plays multiple distinct roles in ascidian embryogenesis.

Amino Acid Sequence↗
PubMed1995

Assessment of portal vein invasion by bile duct cancer using intraductal ultrasonography.

BACKGROUND AND STUDY AIMS: We recently reported on the contribution of intraductal ultrasonography (IDUS) to the regional staging of bile duct cancer, and we present here the first detailed study of the value of IDUS in assessing the portal vein invasion by bile duct cancer. PATIENTS AND METHODS: Preoperative assessment of portal vein invasion was performed by IDUS via a percutaneous tract or via transpapillary route in 18 patients with extrahepatic bile duct cancer. Various probes, with diameters of 1.4, 2.0, 2.4, 2.6, and 3.2 mm, and frequencies of 7.5, 15, 20, and 30 MHz, were used. All patients additionally underwent endoscopic ultrasonography (EUS) and angiography. In the first six cases, the IDUS and EUS images were analyzed retrospectively without the knowledge of operative results or the other imaging tests. In the remaining 12 cases, IDUS and EUS images were prospectively reviewed prior to surgery, without knowledge of the angiographic findings. The gold standard for the results of IDUS, EUS and angiography was the histopathological findings in 17 resected tumors, and the intraoperative findings in one patient who did not undergo resective surgery. RESULTS: IDUS was able to demonstrate the portal vein in all cases. Its accuracy in diagnosing portal vein invasion was 100% for all locations. EUS was useful in assessing portal vein invasion at the middle and distal bile duct (the accuracy was 91%), but was not useful in assessing invasion at the proximal bile duct (the accuracy was 57%). CONCLUSIONS: IDUS proved useful for assessing the extension of cancer invasion into the portal vein, even in proximal bile duct tumors.

Aged↗
PubMed1995

Assessment of hepatic artery invasion by bile duct cancer using intraductal ultrasonography.

BACKGROUND AND STUDY AIMS: This study was performed to clarify the diagnostic accuracy of intraductal ultrasonography (IDUS) in assessing hepatic artery invasion by bile duct cancer. PATIENTS AND METHODS: Preoperative assessment of hepatic artery invasion was performed by IDUS via a percutaneous tract or the transpapillary route in a total of 22 patients with extrahepatic bile duct cancer. The probes used had a diameter of 1.4, 2.0, 2.4, 2.6, and 3.2 mm, and frequencies of 7.5, 15, 20, and 30 MHz. In the first six cases, IDUS images were analyzed retrospectively with no knowledge of the operative results or of the other imaging tests. In the following 16 cases, the IDUS images were prospectively reviewed prior to surgery without knowledge of the angiographic findings. The diagnostic accuracy of IDUS was compared with angiography in all cases, with the histopathological results in 20 resected cases, and with the intraoperative findings in two cases with only surgical exploration. RESULTS: IDUS was able to demonstrate the right hepatic artery in all cases, and its accuracy in diagnosing right hepatic invasion was 100%. However, IDUS was able to visualize the proper hepatic artery in only four cases (18%), and the left hepatic artery in only three cases (14%), respectively. IDUS could not visualize the area outside of the hepatoduodenal ligament, because of its low penetration depth. CONCLUSIONS: IDUS proved useful for assessing the extension of bile duct cancer invasion into the right hepatic artery. However, IDUS did not sufficiently demonstrate the proper hepatic artery and the left hepatic artery for diagnosing vascular involvement.

Aged↗
PubMed1995

Homologous regulation of the calcitonin receptor in mouse osteoclast-like cells and human breast cancer T47D cells.

Calcitonin (CT) down-regulates its receptor in several cancer cell lines, including T47D human breast cancer cells. Removal of CT results in the recovery of CT receptor (CTR) binding. However, homologous regulation of the CTR in osteoclasts is not well understood. To elucidate these phenomena in cells of the osteoclast lineage, mouse osteoblasts and bone marrow cells were cocultured on type 1 collagen gels. For the experiments, osteoclast-like cell (OCL)-enriched populations were subcultured from the collagen gels into multiwell dishes on days 7-8, and CT regulation of the CTR was determined and compared with that in T47D cells. When cells of either type were treated with CT for 1 h and then washed, binding capacity for [125I] salmon CT ([125I]sCT) was decreased dependent upon the preincubating concentration of CT. After removal of CT, the binding capacity in OCLs recovered toward the control level over 12 h. However, in contrast to that in T47D cells, recovery was transient, so that 24 h after removal of CT, the binding capacity in preincubated cells was strikingly reduced compared with that in control cells. This occurred even when the preincubating concentration of CT was too low to cause down-regulation of binding in 1 h. Scatchard analysis showed a decrease in receptor number in CT-treated compared with control OCLs 24 h after CT removal, with unchanged receptor affinity. By autoradiography, decreased CTR density on multinuclear OCLs was indicated. Preexposure of either OCLs or T47D cells to CT caused elevation of intracellular cAMP, which persisted for 6-12 h after removal of CT. In addition, there was desensitization to a rechallenge with CT, which, in T47D cells, recovered by 24-36 h. In contrast, OCLs showed incomplete recovery of desensitization. These data correlated with the results of semiquantitative reverse transcription-polymerase chain reaction studies; the CTR messenger RNA level was increased to about 150% of the control level in sCT-treated T47D cells 18-36 h after sCT removal; the level was markedly decreased to about 20% of the control value in sCT-treated OCLs 12-48 h after sCT removal and remained suppressed. This study suggests that CT-induced homologous down-regulation is a potential cause of the "escape" phenomenon, by producing a population of CT-resistant osteoclasts.

Animals↗
PubMed1995

Expression of the labial group Hox gene HrHox-1 and its alteration induced by retinoic acid in development of the ascidian Halocynthia roretzi.

Ascidian embryogenesis shares several developmental features with vertebrates. Thus, it is presumed that some molecular mechanisms that are critical for vertebrate development may also act in the early development of ascidians. Here, we investigated expression of the ascidian labial group Hox gene HrHox-1 in the development of Halocynthia roretzi. HrHox-1 showed a spatially restricted expression pattern along the anterior-posterior axis, which is remarkably similar to that of the vertebrate gene, Hoxb-1. The expression of HrHox-1, however, was exclusively in tissues of ectoderm origin unlike its vertebrate counterpart. Exposure of the embryos to 10(-6) M all-trans retinoic acid induced a larval phenotype with elimination of the anteriormost structures, the papillae. In this phenotype, the level of HrHox-1 expression was enhanced and ectopic expression was observed at the anterior terminal epidermis where the papillae are otherwise formed. These observations suggest that there are some conserved mechanisms in the spatial regulation of expression of labial group genes in embryogenesis of ascidians and vertebrates.

Amino Acid Sequence↗
PubMed1995

Fungal metabolites. XVIII. New membrane-modifying peptides, trichorozins I-IV, from the fungus Trichoderma harzianum.

New membrane-modifying peptides, trichorozins I-IV, have been isolated from conidia of the fungus Trichoderma harzianum. Their amino acid sequences were clearly determined by spectrometric methods and, furthermore, they were synthesized by the solution-phase method. Trichorozins are a family of the class of peptaibols and are composed of 11 residues including an amino alcohol. Trichorozins exhibited voltage-dependent ion channel-like activity in lipid bilayers.

Amino Acid Sequence↗
PubMed1995

Fungal metabolites. XIX. Structural elucidation of channel-forming peptides, trichorovins-I-XIV, from the fungus Trichoderma viride.

Trichorovins (TV)-I-XIV are new antibiotic peptides obtained from conidia of the fungus Trichoderma viride. The peptide mixture of TVs was repeatedly fractionated by preparative HPLC until individual TVs showed a single peak on their analytical HPLC chromatograms. Nevertheless, FAB-MS or NMR indicated that each of TVs-I-XIV was composed of at least two components. We attempted to elucidate their structures within the fractions by electrospray ionization (ESI)-MS, FAB-MS, FAB-MS/MS and NMR. TVs generally have molecular weights of approximately 1100-1200 Da, and are characterized by an acetylated N-terminus, the presence of an aminoalcohol, e.g. leucinol, isoleucinol or valinol, at the C-terminus, and eleven residues including three alpha-aminoisobutyric acids in the molecule. Thus, it was determined that TVs belong to the class of peptaibols.

Amino Acid Sequence↗
PubMed1995

Magnetic resonance imaging of multiple brain abscesses of the bilateral basal ganglia.

A 64-year-old woman developed multiple brain abscesses of the basal ganglia associated with Klebsiella pneumoniae septicemia. Magnetic resonance (MR) images showed three different stages of the brain abscesses. The images of early cerebritis of this site mimicked lacunar infarctions or dilated Virchow-Robin spaces. The differentiation of the brain abscess from lacunae and dilated Virchow-Robin spaces is discussed, together with the evolution of the brain abscesses on MR images.

Basal Ganglia↗
PubMed1995

[Gynecologic endoscopic surgery].

Recently, endoscopic operation represents a major innovation in various fields of surgery. In the gynecologic fields, hysterectomy, salpingo-oophorectomy, ovarian cystectomy, myomectomy and even lymphadenectomy are performed under the assistance of laparoscopy and hysteroscopy at present. Based on our clinical experiences of endoscopy, we have started endoscopic operation since 1992. The endoscopic operation in our department was reviewed in regard to methods and clinical results.

Endoscopy↗
PubMed1995

Dysgerminoma of the ovary with hypercalcemia associated with elevated parathyroid hormone-related protein.

The purpose of the present paper is to present a rare case of dysgerminoma of the ovary with hypercalcemia showing elevation of multiple serum tumor markers including parathyroid hormone-related protein (PTH-rP). An 18-year-old unmarried woman, with ovarian dysgerminoma showing hypercalcemia and elevated serum PTH-rP, received six courses of a combination chemotherapy consisting of bleomycin, etoposide and cisplatin after her first surgery, and had no evidence of recurrence approximately 30 months after completing the chemotherapy.

Adolescent↗
PubMed1995

[A case of peritoneal metastasis from retroperitoneal yolk sac tumor diagnosed by 67Ga-scan and 18F-FDG-PET].

Yolk sac tumor is one of the histological types of germ cell tumors. Primary retroperitoneal germ cell tumors are extremely rare neoplasms. We report a case of peritoneal metastasis after resection of a primary retroperitoneal germ cell tumor. The peritoneal metastases were detected by 67Ga-scan when CT did not suggest metastatic lesions while the level of alphafetoprotein was still elevated. The 67Ga-scan showed multiple hot spots in the abdomen and pelvis 72 hours after intravenous injection of the tracer and no changes were observed in serial scan taken 6 hours after the first scan. These findings were strongly suggested the dissemination of the malignant tumors. A PET study with 18F-fluorodeoxyglucose was performed and showed extensive uptake in the intraabdominal and intrapelvic cavity. It was also useful for understanding the extension and distribution of the peritoneal metastatic lesions. The sites of the accumulation of 18F-fluorodeoxyglucose corresponded to the results found in postmortem.

Adult↗
PubMed1995

[Complications of endocardial biopsy in heart transplant patients].

Despite the increasing use of alternative techniques, endomyocardial biopsy remains the primary method for diagnosing cardiac allograft rejection. Between March 1986 and May 1994, 2,894 endomyocardial biopsies performed on 183 heart transplant patients were reviewed. A total of 53 (1.8%) complications occurred. 33 (1.1%) complications were associated with the introduction, including carotid puncture (0.9%), neurological reaction (0.1%), and pneumothorax (0.1%). Complications during biopsy included arrhythmias (0.4%) and ventricular perforation (0.2%). In addition, we observed three episodes of allergic reaction to a reusable biotome, three episodes of liver biopsy, and one case of pacemaker dislodgement. All complications were without significant long-term sequelae. In contrast to the cardiomyopathy population, no severe ventricular perforations or deaths occurred. Thus although endomyocardial biopsy has some risk, it continues to be a safe and effective way of monitoring rejection.

Adolescent↗