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Featured researches published by Katsuaki Ukai.


Journal of Gastroenterology and Hepatology | 1993

Subcutaneous seeding of small hepatocellular carcinoma after fine needle aspiration biopsy

Nobuo Yamada; Haruhide Shinzawa; Katsuaki Ukai; Hiroto Wakabayashi; Hitoshi Togashi; Tsuneo A. Takahashi; Nobuo Seo; Shuichi Ishiyama; Masaru Tsukamoto; Shigemi Fuyama

Ultrasonically guided fine needle (21 gauge) aspiration biopsy (FNAB) was performed on a patient with a hepatocellular carcinoma (HCC) measuring 1.5 × 1.5 cm in segment VI of the liver. The tumour was located just beneath the liver surface. Subsegmentectomy of segment VI was performed. Twelve months after the biopsy and 10 months after the operation, levels of alpha‐fetoprotein (AFP) and protein induced by Vitamin K absence or antagonist‐II (PIVKA‐II) increased gradually without any evidence of recurrence of HCC in the liver. Thirteen months after the biopsy, the patient palpated a hard subcutaneous nodule 1.5 cm in diameter in the right lower anterior chest wall at the insertion site of the biopsy needle. A subcutaneous tumour was excised and histological examination revealed moderately differentiated HCC. The levels of AFP and PIVKA‐II normalized thereafter. These tumour markers were therefore useful for diagnosing the subcutaneous nodule as a metastatic HCC. The patient is currently doing well without further recurrence of HCC or needle‐tract seeding 23 months after subsegmentectomy and 11 months after excision of the subcutaneous tumour.


Digestive Diseases and Sciences | 1994

Treatment of symptomatic hepatic cysts by percutaneous instillation of minocycline hydrochloride

Nobuo Yamada; Haruhide Shinzawa; Katsuaki Ukai; Naohiko Makino; Takaaki Matsuhashi; Hiroto Wakabayashi; Hitoshi Togashi; Tsuneo Takahashi

Nine patients with 16 symptomatic nonneoplastic congenital hepatic cysts were treated prospectively by ultrasonically guided percutaneous minocycline hydrochloride injection, and the usefulness of this treatment was evaluated. Seven of the patients had multiple hepatic cysts, and two solitary cysts. All the patients were women, ranging in age from 36 to 81 years. After cystic fluid had been aspirated with a 21-gauge PTC needle, minocycline hydrochloride was injected into all the cysts. The minocycline hydrochloride was dissolved in saline at a concentration of 200 mg in 9 ml, and mixed with 1 ml of 2% mepivacaine hydrochloride. The total quantity of minocycline hydrochloride injected varied from 100 mg to 1200 mg per hepatic cyst, depending on its size. Total or subtotal regression of the cysts was observed in all patients during follow-up periods ranging from 15 to 35 months. Seven patients became symptom-free, one showed symptom reduction, and one showed no change in symptoms. Minor side effects, eg, transient abdominal pain, slight right shoulder pain, and temperature elevation, were noted in three patients respectively. On the basis of these results, we conclude that ultrasonically guided percutaneous minocycline hydrochloride injection is useful for the treatment of symptomatic hepatic cysts.


Pathology International | 1990

PROLIFERATION KINETICS OF RAT KUPFFER CELLS AFTER PARTIAL HEPATECTOMY : IMMUNOHISTOCHEMICAL AND ULTRASTRUCTURAL ANALYSIS

Katsuaki Ukai; Kazuo Terashima; Yutaka Imai; Haruhide Shinzawa; Yoshimi Okuyama; Tsuneo Takahashi; Makoto Ishikawa

In an effort to settle the conflicting views on the proliferation kinetics of Kupffer cells (Kc), we performed 2/3 partial hepatectomy on rats injected with Pelikan ink. Using an anti‐rat macrophage monoclonal antibody, ED 2, we evaluated the numerical changes in total, carbon‐positive ED 2+ cells and carbon‐negative ED 2+ cells in the portal and central area. We also analyzed the ultrastructure and peroxidase cytochemistry of various types of cells observed during regeneration. The total numbers of ED 2+ cells in the remaining liver increased rapidly from day 2 to 5, and the number of dividing ED 2+ cells reached a maximum on day 2. Thus, the numerical increase in ED 2+ cells corresponded to the division phase. In contrast, the carbon‐labeling experiment showed a continuous increase of carbon negative ED 2+ cells from day 2 to 7. In the central area where division was less frequent, the proportion of carbon‐positive cells decreased markedly to 50% on day 7, as against 97% in control rats. These findings suggest the possibility of an influx of carbon‐negative Kc in addition to cell division. Ultrastructurally, the presence of carbon‐negative “small Kc” and “immature Kc” with morphological features different from those of carbon‐positive Kc was demonstrated. Such carbon‐negative Kc with a high nucleus‐to‐cytoplasm ratio and rather few phagosomes, were not observed in control rats. Furthermore, we demonstrated two types of possible precursor cell, i.e. “transitional” forms between monocytes and Kc, and “immature macrophages”. The former showed peroxidase activity in some lysosomes as well as in the rough endoplasmic reticulum and nuclear envelope. Our result indicated that the proliferation kinetics of Kc depend upon both local proliferation and influx.


Pathology International | 1988

A new monoclonal antibody, UFT-4, reacting with rat Kupffer cells. Immunohistochemical and immunoelectron microscopical analysis with reestimation of the reticuloendothelial system.

Katsuaki Ukai; Kazuo Terashima; Yoichi Fujii; Yutaka Imai

A new monoclonal antibody, designated UFT‐4, reacting with rat Kupffer cells, was produced using sinusoidal liver‐cell fraction as an immunogen. Immuno‐histochemically, UFT‐4 reacted with Kupffer cells, interdigitating cells (IDCs), sinus endothelial cells of the spleen, a proportion of reticulum cells, smooth muscle fibers, choroid plexus epithelia and some macrophages. Immunoelectron microscopy disclosed two types of intracytoplasmic positivity: a striated type and a diffuse type. Both appeared to depend on variations in the quantity and distribution of the same antigen. On the other hand, UFT‐4 gave a negative result for blood monocytes and most macrophages in lymphatic sinuses, lymphoid follicles, splenic red pulp and loose connective tissue. Cells positive for UFT‐4 were mostly considered to belong to a narrow spectrum of the classical reticuloendothelial system, explaining the close relationship existing between some endothelia and some macrophages or reticulum cells. SDS‐PAGE analysis of immunoprecipitates showed that the antigen reacting with UFT‐4 was of molecule of 36–42 kDa under reducing conditions in the presence of 2‐mercaptoethanol. The present results suggest that UFT‐4 will be very useful for the study of Kupffer cells and for reconsidering their origin and destination. ACTA PATHOL JPN 38: 1391–1403, 1988.


Advances in Experimental Medicine and Biology | 1988

Morphologicl Diversity of DRC-1 Pospitive Cells: Human Follicular Dendritic Cells and their Relatives

Kazuo Terashma; Katsuaki Ukai; Katsushi Tajima; Fumiaki Yuda; Yutaka Imai

Follicular dendritic cells (FDC) and their relatives of the human tonsils and lymph nodes were immunoelectron microscopically analyzed with a monoclonal antibody DRC-1 (DAKO) in a combination with an enzymatic isolation technique. DRC-1+ cells were largely grouped into three type A (large mono- to multinucleated, sea anemone-fashioned, bearing labyrinth structures, in germinal center), type B (oligodendritic or stellate, medium-sized, in the corona and the primary follicle) and type C (individually located, medium-sized. lymphoid cell-fashioned, outside follicles). Type C were found in hyperplastic lymphoid tissue as well as in some granulation tissue. The DRC-1+ mononuclear cells were curiously encountered in the peripheral blood of some autoimmune disease patients in contrast with no identification in healthy persons. Furthermore some DRC-1+ cells obtained from autoimmune patient were confirmed to proliferate in culture.


Case Reports in Gastroenterology | 2016

A Case of Intussusception Associated with Pneumatosis Cystoides Intestinalis.

Taku Fujiya; Masahiro Iwabuchi; Mikako Sugimura; Katsuaki Ukai; Keiichi Tadokoro

Pneumatosis cystoides intestinalis (PCI) is an uncommon disease that generally lacks symptoms and is rarely associated with intussusception. A 29-year-old man visited our hospital for right upper abdominal pain. Computed tomography (CT) scan revealed multiple air-filled cysts along the intestinal wall and a pseudokidney sign in the transverse colon. A gastrographin enema examination showed a so-called crab finger appearance and multiple elevated translucency in the transverse colon. From these findings, the diagnosis of intussusception associated with PCI was made. The enema and manipulative reduction improved the intussusception. Comparing the enema findings before and after the reduction, we thought that mobile cecum could play an important role in the intussusception. Colonoscopy was performed after the reduction and showed multiple elevated lesions in the ascending colon, which were similar to cluster of grapes. The CT scan of the next day revealed no recurrence of the intussusception, and the patient has not had symptoms of recurrence ever since.


Digestive Endoscopy | 1992

Quantitative Measurement of Fluorescent Intensity of the Rat Liver Surface Using Video Fluorescence Laparoscopy Following Intravenous Fluorescein Injection

Hiroto Wakabayashi; Haruhide Shinzawa; Hirotaka Toda; Ichiro Aoyama; Makoto Kuboki; Masamichi Ishibashi; Takahumi Saitoh; Katsuaki Ukai; Nobuo Yamada; Hitoshi Togashi; Tsuneo Takahashi; Makoto Ishikawa

Abstract: A new method for the quantitative measurement of fluorescent intensity of the rats liver surface after fluorescein injection is described. The measuring system of fluorescent intensity on the rat liver surface consisted of a video laparoscopy with a video densitometer. An excitation filter was placed in the light source and an absorbing filter was attached to the eyepiece of the magnifying scope in this fluorescence video laparoscopy system. Fluorescein was injected intravenously into the inferior vena cava. Video fluorescence images of the liver surface were recorded with a CCD TV camera which was connected to the scope. In measuring the mean intensity of video images, a region of interest was designated on the TV monitor. The fluorescent intensity in this region was measured by a video densitometer and expressed in volts. The time‐intensity curve was graphically presented using a pen recorder. In this way, the time course of the liver surface fluorescent intensity could be analyzed with data expressed in volts. In normal livers, the fluorescent intensity began to rise 4.0 ± 0.5 seconds after fluorescein injection and reached a peak at 14.4 ± 1.5 seconds. Thereafter, the intensity fell slightly but then rose again to a second peak 170±50 seconds after injection.


Hepatology | 1991

Superoxide is involved in the pathogenesis of paraquat‐induced injury in cultured rat liver slices

Hitoshi Togashi; Haruhide Shinzawa; Hiroto Wakabayashi; Toichiro Nakamura; Huang Yong; Nobuo Yamada; Katsuaki Ukai; Yoshimi Okuyama; Tsuneo Takahashi; Makoto Ishikawa


Archives of Gynecology and Obstetrics | 2013

Flare up of ulcerative colitis during pregnancy treated by adsorptive granulocyte and monocyte apheresis: therapeutic outcomes in three pregnant patients

Hiroki Takahashi; Kaori Sugawara; Mikako Sugimura; Masahiro Iwabuchi; Yutaka Mano; Katsuaki Ukai; Keiichi Tadokoro


Histology and Histopathology | 1989

Ultrastructural localization of Cu, Zn-SOD in hepatocytes of patients with various liver diseases.

Katsuaki Ukai; Hitoshi Togashi; Makoto Ishikawa; Tsuneo A. Takahashi; Takafumi Saito; Haruhide Shinzawa; Yutaka Imai; Michio Dobashi; Hiroto Wakabayashi

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