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1.
Endosc Ultrasound ; 3(Suppl 1): S13, 2014 Apr.
Article in English | MEDLINE | ID: mdl-26425511

ABSTRACT

INTRODUCTION: In autoimmune pancreatitis (AIP), veins of various sizes are highly affected by obliterative phlebitis without damage to arteries, in contrast, the involvement of both arteries and veins is observed in the mass of pancreatic cancer. A vascular image without blooming artifact in the pancreas is clearly observed in the directional eFLOW (Prosound α10, Aloca Co., Tokyo, Japan) color mode using contrast-enhanced color-Doppler endoscopic ultrasonography (CC-EUS) despite perfusion of the contrast media. AIMS AND METHODS: The aim of this study was to compare the vascular structure of AIP with that of pancreatic cancer using CC-EUS. We evaluated the perfusion image and the vascular image of the mass in AIP patients (11) with an increase in serum IgG4 levels (477.3 ± 314.2 IU/mL) and in pancreatic cancer patients (11) with elevated serum CA19-9 levels (49839.0 ± 80061.6 mg/dl), on CC-EUS. Perfusion images were obtained at 20-30 s after injection of a contrast agent, Sonazoid (GE Healthcare AG, Oslo, Norway), by extended pure harmonic detection mode and were assessed as to homogeneity or heterogeneity (containing partial low echoic areas or multiple spotty low echoic areas) enhancement. The vascular image was assessed in the directional eFLOW color mode despite perfusion of the contrast media (40-50 s after injection of Sonazoid) as to the presence of a dendritic vessel network or only a few feeder vessels. The parameters for imaging were as follows: Mechanical index, 0.22-0.24; transmission frequency, 5.0 MHz; and receiving frequency, 5.0 MHz. The Chi-square test or Fisher's exact test was used for comparison of categorical data of the two groups when appropriate. This study was approved by the institutional review board of Sendai City Medical Center. All subjects gave informed consent. RESULTS: A homogenous pattern in perfusion imaging was seen in 73% of patients with AIP (8/11) and 55% of those with pancreatic cancer (6/11). The rates were not significantly different between the two groups (P = 0.33). In the other patients with a heterogenous pattern, multiple spotty low echoic areas were seen in 33% (1/3) and 80% (4/5) in each group, respectively. A dendritic vascular pattern in the eFLOW color mode was seen in 82% (9/11) of patients with AIP, but was not seen in any of patients with pancreatic cancer. The other patients with AIP (18%) and all patients with pancreatic cancer showed only a few feeder vessels in the mass on CC-EUS. CONCLUSION: The eFLOW color mode using Sonazoid may be useful for evaluating the vascular structure of AIP for differential diagnosis from pancreatic cancer.

2.
Clin Exp Allergy ; 32(4): 595-601, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11972608

ABSTRACT

BACKGROUND: The hypertrophy/hyperplasia of airway smooth muscle (ASM) cells is one of the characteristic features of bronchial asthma. This structural change leads to the thickening of airway walls resulting in the amplification of airway narrowing. However, the pathogenesis of this structural change has not yet been determined. Eosinophils, which play a pathogenic role in asthma, have been demonstrated to have proliferative effects on fibroblasts and vascular smooth muscle cells. OBJECTIVE: We attempted to investigate the potential of eosinophils to induce the proliferation of ASM cells. METHODS: We examined the effect of lysates of eosinophils purified from peripheral blood of healthy donors on cultured human ASM cell proliferation. RESULTS: Eosinophil lysates significantly induced ASM cell proliferation in time- and dose-dependent manners, reaching a maximum on day 6 at 50% of eosinophil lysates (6.0 +/- 0.7 x 104 [mean +/- SD] /well, n = 5 vs. 4.5 +/- 1.1 x 104/well, n = 5; P < 0.05). This proliferative activity was heat-sensitive and recovered in the soluble fraction of the eosinophil lysates. Furthermore, the molecular weight of the mitogenic activity in the soluble fraction was identified as lower than 10 kDa. The inhibitory activity to ASM cell proliferation was also found in the insoluble fraction of the lysates. CONCLUSION: These results indicate that circulating eosinophils store mitogenic activity for ASM cells, suggesting that eosinophils might contribute to the development of the hyperplasia of ASM cells in asthmatics through the release of the stored mitogenic activity upon stimulation at the site of inflammation.


Subject(s)
Eosinophils/physiology , Muscle, Smooth/cytology , Respiratory System/cytology , Aged , Cell Division , Cell Extracts/analysis , Cell Extracts/pharmacology , Cells, Cultured , Female , Humans , Kinetics , Male , Middle Aged , Mitogens/pharmacology
3.
Nature ; 386(6627): 796-804, 1997 Apr 24.
Article in English | MEDLINE | ID: mdl-9126737

ABSTRACT

The DCC (Deleted in colorectal cancer) gene was first identified as a candidate for a tumour-suppressor gene on human chromosome 18q. More recently, in vitro studies in rodents have provided evidence that DCC might function as a receptor for the axonal chemoattractant netrin-1. Inactivation of the murine Dcc gene caused defects in axonal projections that are similar to those observed in netrin-1-deficient mice but did not affect growth, differentiation, morphogenesis or tumorigenesis in mouse intestine. These observations fail to support a tumour-suppressor function for Dcc, but are consistent with the hypothesis that DCC is a component of a receptor for netrin-1.


Subject(s)
Cell Adhesion Molecules/physiology , Genes, DCC , Intestinal Neoplasms/genetics , Mutagenesis , Tumor Suppressor Proteins , Animals , Axons/pathology , Brain/abnormalities , Brain/embryology , Brain Neoplasms/genetics , Cell Adhesion Molecules/genetics , Cell Division , Chimera , Chromosome Mapping , Colorectal Neoplasms/genetics , DCC Receptor , Gene Targeting , Humans , Intestinal Mucosa/pathology , Intestinal Polyps/genetics , Mice , Mice, Inbred C57BL , Nerve Growth Factors/physiology , Netrin-1 , Phenotype , Receptors, Cell Surface/metabolism , Spinal Cord/abnormalities , Spinal Cord/embryology
4.
Nature ; 386(6627): 833-8, 1997 Apr 24.
Article in English | MEDLINE | ID: mdl-9126742

ABSTRACT

In the developing nervous system, migrating cells and axons are guided to their targets by cues in the extracellular environment. The netrins are a family of phylogenetically conserved guidance cues that can function as diffusible attractants and repellents for different classes of cells and axons. In vertebrates, insects and nematodes, members of the DCC subfamily of the immunoglobulin superfamily have been implicated as receptors that are involved in migration towards netrin sources. The mechanisms that direct migration away from netrin sources (presumed repulsions) are less well understood. In Caenorhabditis elegans, the transmembrane protein UNC-5 (ref. 14) has been implicated in these responses, as loss of unc-5 function causes migration defects and ectopic expression of unc-5 in some neurons can redirect their axons away from a netrin source. Whether UNC-5 is a netrin receptor or simply an accessory to such a receptor has not, however, been defined. We now report the identification of two vertebrate homologues of UNC-5 which, with UNC-5 and the product of the mouse rostral cerebellar malformation gene (rcm), define a new subfamily of the immunoglobulin superfamily, and whose messenger RNAs show prominent expression in various classes of differentiating neurons. We provide evidence that these two UNC-5 homologues, as well as the rcm gene product, are netrin-binding proteins, supporting the hypothesis that UNC-5 and its relatives are netrin receptors.


Subject(s)
Caenorhabditis elegans Proteins , Caenorhabditis elegans/chemistry , Helminth Proteins/chemistry , Membrane Proteins/chemistry , Receptors, Cell Surface/physiology , Receptors, Growth Factor/chemistry , Receptors, Nerve Growth Factor/physiology , Amino Acid Sequence , Animals , Axons/physiology , Cell Movement/physiology , Gene Expression , Humans , Molecular Sequence Data , Nerve Growth Factors/metabolism , Netrin Receptors , Netrin-1 , Neurons/cytology , Protein Conformation , RNA, Messenger/metabolism , Rats , Receptors, Cell Surface/chemistry , Receptors, Cell Surface/genetics , Receptors, Nerve Growth Factor/chemistry , Receptors, Nerve Growth Factor/genetics , Sequence Homology, Amino Acid , Spinal Cord/embryology , Spinal Cord/metabolism , Transfection , Tumor Suppressor Proteins
5.
Trends Cell Biol ; 7(2): 47, 1997 Feb.
Article in English | MEDLINE | ID: mdl-17708901
7.
Cell ; 87(2): 175-85, 1996 Oct 18.
Article in English | MEDLINE | ID: mdl-8861902

ABSTRACT

The guidance of developing axons in the nervous system is mediated partly by diffusible chemoattractants secreted by axonal target cells. Netrins are chemoattractants for commissural axons in the vertebrate spinal cord, but the mechanisms through which they produce their effects are unknown. We show that Deleted in Colorectal Cancer (DCC), a transmembrane protein of the immunoglobulin superfamily, is expressed on spinal commissural axons and possesses netrin-1-binding activity. Moreover, an antibody to DCC selectively blocks the netrin-1-dependent outgrowth of commissural axons in vitro. These results indicate that DCC is a receptor or a component of a receptor that mediates the effects of netrin-1 on commissural axons, and they complement genetic evidence for interactions between DCC and netrin homologs in C. elegans and Drosophila.


Subject(s)
Cell Adhesion Molecules/physiology , Membrane Proteins/metabolism , Nerve Growth Factors/physiology , Receptors, Cell Surface/genetics , Tumor Suppressor Proteins , Amino Acid Sequence , Animals , Axons/physiology , Base Sequence , Cells, Cultured , Gene Expression Regulation, Developmental , Genes, Tumor Suppressor , In Situ Hybridization , Membrane Proteins/genetics , Molecular Sequence Data , Netrin-1 , Protein Binding , RNA, Messenger/genetics , Rats , Recombinant Proteins , Signal Transduction , Spinal Cord/embryology , Spinal Cord/physiology
8.
Abdom Imaging ; 20(3): 259-61, 1995.
Article in English | MEDLINE | ID: mdl-7620421

ABSTRACT

We report a case of mesenteric chylous cyst diagnosed preoperatively by ultrasonography (US) and computed tomography (CT). Both demonstrated a unilocular cystic mass with a fluid-fluid level. The CT number of the two components indicated fat density and water density and with shaking or positional changes, the contents displayed miscibility. The tumor changed its position during hospitalization. Both features are considered to be quite diagnostic of this condition.


Subject(s)
Chyle , Mesenteric Cyst/diagnosis , Tomography, X-Ray Computed , Ultrasonography , Diagnosis, Differential , Female , Humans , Mesenteric Cyst/pathology , Mesenteric Cyst/surgery , Mesentery/pathology , Mesentery/surgery , Middle Aged
9.
Article in English | MEDLINE | ID: mdl-18263209

ABSTRACT

An asynchronous spread spectrum (SS) modem in the 2.45-GHz band has been implemented using an efficient ZnO-SiO(2)-Si surface acoustic wave (SAW) convolver. The modem, which can operate under full duplex transmission is based on a direct-sequence/code-shift-keying (DS/CSK) method for the modulation. Pseudonoise (PN) codes are chosen from a preferred pair of m-sequences of period 127, and the code rate is 14 MHz. The demodulation is carried out asynchronously, utilizing the coherent correlation characteristics of the SAW convolver. The main interference caused by a transmitted signal in the modem itself is effectively reduced by an RF isolator and the SS process gain. Adequate self-jamming rejection capability has been confirmed; a bit error rate of 10(-6) is observed at -78.3 dB of a desired-to-undesired-signal ratio using an artificial transmission line.

10.
No Shinkei Geka ; 9(7): 843-8, 1981 Jun.
Article in Japanese | MEDLINE | ID: mdl-7266768

ABSTRACT

Intracranial mesenchymal chondrosarcoma is very rare, only 14 cases being reported in Europe and in the United States of America. Recently we experienced a case in which the follow-up indicating computed tomograms (CT) demonstrated interesting data on the radiosensitivity of this tumor. The patient, a 14-year-old female was admitted to out hospital with the complaint of left hemiplegia which had gradually progressed. CT revealed an area spreading upward from the right median base of the skull and consisted of two components showing (A) a density as high as that of calcium and (B) a density higher than that of surrounding brain tissue, but much lower than that of calcium. Temporoparietal craniotomy was performed to react approximately one-half of the tumor. Histological finding revealed mesenchymal chondrosarcoma. The component-A was though to be a cartilaginous tissue, and-B to be an undifferentiated mesenchymal tissue. Postoperative irradiation of 7,000 rad was initiated. The effect of radiotherapy as seen on computed tomograms is as follows, (1) decrease in the volume of the tumor by 26%, (2) decrease in density and enhancement of the area which is considered to be the undifferentiated mesenchymal cells, (3) mild reduction of the area which is considered to be the cartilaginous tissue, and (4) a very high density of the entire tumor similar in degree to that of the bone one year later. These results suggested that radiotherapy is effective for this tumor.


Subject(s)
Brain Neoplasms/diagnostic imaging , Chondrosarcoma/diagnostic imaging , Tomography, X-Ray Computed , Adolescent , Brain Neoplasms/radiotherapy , Brain Neoplasms/surgery , Chondrosarcoma/radiotherapy , Chondrosarcoma/surgery , Female , Humans
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