Invited Review Articles
Cell Surface Glycoproteins: Biochemical, Immunological and Molecular Biological Studies
TAKASHI MURAMATSU
pg(s) 95-108
<Close> - < PDF >
This article briefly summarizes the author's contribution to the study of cell surface glycoproteins. At first, much effort was devoted to developing analytical methods, especially exoglycosidases and endoglycosidases. An endo-beta-N-acetylglucosaminidase found in Streptococcus pneumoniae was the first example of an endoglycosidase acting on glycoproteins. A combination of radioactive labeling, glycosidase digestion and lectin affinity chromatography enabled the characterization of carbohydrate moieties of cell surface glycoproteins derived from cultured cells. Application of the method to teratocarcinoma stem cells and preimplantation mouse embryos led to the discovery of marked changes in the carbohydrate moieties of cell surface glycoproteins during embryogenesis. Combining biochemical and immunohistochemical methods, an overall picture was obtained for carbohydrate changes in early embryogenesis of the mouse, and molecular biological approaches have been adopted to determine their biological significance. Furthermore, some core proteins carrying developmentally regulated carbohydrate markers were found and characterized by molecular cloning. One example of such a protein is embigin, which enhances integrin-mediated cell-substratum adhesion and established the existence of a new group in the immunoglobulin superfamily. Carbohydrate immunochemical markers useful in the analysis of mouse embryogenesis were also found to be effective in the classification of human carcinomas with respect to metastatic potential.
Current Status of Pancreatic Stone Protein
TETSUO HAYAKAWA, SATORU NARUSE, MOTOJI KITAGAWA, YASUYUKI NAKAE and SHINOBU HAYAKAWA
pg(s)109-118
<Close> - < PDF >
Pancreatic stone protein (PSP) has been argued to play a crucial role in intraductal pancreatic stone formation in chronic pancreatitis. PSP was initially reported to inhibit calcium carbonate precipitation from human pancreatic juice and to be decreased in pancreatic secretions from patients with chronic pancreatitis. Recent clinical investigations have further demonstrated elevation of PSP in the serum and urine of patients with renal disease as well as pancreatic disease. However, the PSP reduction in pancreatic secretion in chronic pancreatitis remains controversial. Therefore, we review the current concept of PSP.
Original Papers
Effects of Protein Synthesis Inhibitor and Antimicrotubular Agent on Transepithelial Movement of 3H-Androgens in the Rat Caput Epididymis
MASANORI YAMAMOTO, HATSUKI HIBI, YOSHIKAZU TSUJI and KOJI MIYAKE
pg(s)119-126
<Close> - < PDF >
The effects of protein synthesis inhibition and disassembly of microtubules in the epididymal epithelia on proluminal movement of 3H-androgens were investigated by using in vivo microperifusion of 3H-testosterone and subsequent micropuncture to obtain peritubular and intraluminal fluids of caput epididymal tubules. Cycloheximide (100 micrograms/ml) was used as protein synthesis inhibitor. Nocodazole (3 micrograms/ml) was used to depolymerize microtubules in the cell. The perifusion fluid was Minimum Essential Medium containing 26.7 microCi/ml 3H-testosterone and 1.3 microCi/ml 14C-polyethyleneglycol (14C-PEG), or the same fluid supplemented with cycloheximide or nocodazole. Radioactivity of 3H-androgen and 14C-PEG in perifusion and intraluminal fluids was determined at one hour after initiation of the sustaining perifusion, and the percentage of radioactivity of 3H-androgen and 14C-PEG appearing in the intraluminal fluid to that in the peritubular fluid was determined. Proluminal movement of 3H-androgens into the caput epididymal tubules in the control rats was 323.4 +/- 73.2%. This value was significantly reduced to 121.8 +/- 13% by addition of cycloheximide to the perifusion fluid (p < 0.01). Transepithelial movement of 3H-androgen in the caput epididymis was significantly decreased to 86.6 +/- 5.3% by exposure of the epididymal tubules to nocodazole (p < 0.01). Inhibition of protein synthesis and disassembly of microtubules in the epididymal epithelial cells completely eliminated antigrade proluminal movement of 3H-androgen into the tubules. Study of the incorporation of 35S-Methionine into epididymal tissue protein revealed significant reduction of the quantity of radiolabeled proteins in the perifused tissue with fluid containing cycloheximide (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
Fundamental and Clinical Evaluation of Chest Computed Tomography Imaging in Detectability of Pulmonary Nodule
NICOLAS MILLA, KENGO ITO, MITSURU IKEDA, KIYOKO NAKAMURA, MITSUHIKO HIROSE and TAKEO ISHIGAKI
pg(s)127-132
<Close> - < PDF >
Fundamental and clinical evaluation of chest CT imaging in detectability of pulmonary nodules was carried out in comparison with projection chest radiography including conventional screen-film system, advanced multiple beam equalization radiography (AMBER System), and computed radiography with imaging plate (CR). Detectability of simulated nodules in the fundamental study and of metastatic pulmonary nodules in ten patients in the clinical study was analysed by five radiologists. CT found the greatest number of nodules and also showed the highest sensitivity in detecting nodules of less than 5 mm in both the fundamental and clinical studies. The ability of computed tomography to visualize small pulmonary nodules may make it a possible substitute for chest radiography as the primary mass screening method, and as the examination method for small metastatic nodules (less than 5 mm) in patients with extrathoracic malignancy. There was no significant difference between conventional radiography, AMBER, and CR in the number of detected nodules.
Effect of Albumin on Proluminal Movement of 3H-Androgen into Seminiferous and Epididymal Tubules and Androgen Binding in the Interstitium of the Testis and Epididymis after Perifusion with Fluid Containing Albumin
MASANORI YAMAMOTO, HATSUKI HIBI and KOJI MIYAKE
pg(s)133-142
<Close> - < PDF >
Effect of albumin on proluminal androgen movement from the peritubular space to the intratubular fluids of the adult rat testis and epididymis was examined by using in vivo microperifusion and subsequent micro-puncture of the seminiferous tubules and caput epididymal tubules. Tubules were perfused with four different fluids: (1) Minimum Essential Medium (MEM) containing 3H-testosterone and 14C-polyethyleneglycol (PEG) alone; (2) MEM + 8 mg/ml Bovine Serum Albumin (BSA) containing the same radiolabeled compounds as above; (3) MEM + 80 mg/ml albumin containing the same radiolabeled compounds as above; and (4) Testosterone-free rat serum containing the same radiolabeled compounds as above. Bound 3H-androgens in the interstitial fluids of the testis and epididymis after one-hour perifusion with the four different fluids above were measured by charcoal assay. In the testis, proluminal 3H-androgen movement was not significantly altered by addition of albumin to the perifusion fluid (p = 0.08). Bound 3H-androgens in the interstitial fluid after perifusion were significantly increased with increasing albumin concentrations in the perifusion fluid. In the caput epididymis, proluminal 3H-androgen movement was significantly decreased with increasing albumin concentration in the perifusion fluid. Bound 3H-androgens in the interstitial fluid after perifusion were significantly increased with increasing albumin concentrations in the perifusion fluid (p < 0.05). These findings suggest that proluminal transepithelial movement of 3H-androgens in the reproductive tract could be influenced by the presence of albumin, androgen-binding protein or some other binding protein in the peritubular space.
The Localization of Basic Fibroblast Growth Factor (FGF-2) in Rat Submandibular Glands
YOSHIYUKI HIRAMATSU, HIDEAKI KAGAMI, KENICHI KOSAKI, TOSHIO SHIGETOMI, MINORU UEDA, SHIGERU KOBAYASHI and MASAHIRO SAKANAKA
pg(s)143-152
<Close> - < PDF >
The immunohistochemical localization of basic fibroblast growth factor (FGF-2) in the submandibular glands of the rat was investigated by use of an antiserum to FGF-2. Nerve fiber bundles with FGF-2-immunoreactivity were found in association with interlobular ducts and blood vessels; they dissociated into single immunoreactive nerve fibers perhaps to terminate in proximity to acinar cells, or to form a reticular fiber network within the tunica adventitia of blood vessels. The FGF-2-immunoreactive neurons were located in the submandibular ganglia, but not in the superior cervical ganglia; hence, at least some of these immunoreactive nerve fibers probably come from the submandibular ganglia and are of parasympathetic origin. Most of the epithelial cells of the intercalated and collecting ducts showed notable FGF-2 immunoreactivity. The characteristic distribution of FGF-2 immunoreactivity in both the neuronal and epithelial tissues of the salivary glands suggests a role of this growth factor in complex physiological processes within the salivary glands.
Biochemical Improvement of Chronic Hepatitis C after Gastrointestinal Bleeding
SHOSHI KATO, MOTOHIRO ARAO, JUNSUKE KURIKI, TSUNEAKI TAGAYA, SATOSHI TAKIYA, KATSUMI KATO, TOSHIKUNI TAKIKAWA and HISAO HAYASHI
pg(s)153-157
<Close> - < PDF >
Although chronic hepatitis C is frequently complicated by iron overload, it remains unclear whether iron cytotoxicity is involved in the disease process. Five patients with chronic hepatitis C showed rapid reduction of serum aminotransferase activity after gastrointestinal bleeding. Posthemorrhagic reduction of liver enzyme levels lasted for more than one week. Anemia was associated with a reduction of serum ferritin concentration. Considering the short half-lives of circulating liver enzymes, reduced release of enzymes, that is inactivation of cell lysis, is the likely cause of the improved biochemical indices. Reactive iron, which is cytotoxic for patients infected by HCV, may be rapidly incorporated into hemoglobin when erythropoiesis is stimulated. Our observation also suggests that intensive iron removal by phlebotomy is a safe, economic treatment for patients with chronic hepatitis C.
The Influence of Biodynamic Factors on the Absorption of Vibration Energy in the Human Hand and Arm
LAGE BURSTRÖM
pg(s)159-167
<Close> - < PDF >
A possible basis for risk assessment for hand-transmitted vibration may be to determine the quantity of energy absorbed in the human hand and arm. In the present study the mechanical energy absorption in the hand-arm system has been measured on 10 healthy subjects during exposure to random vibration with constant velocity spectrum. In the study, the influence of various conditions, such as vibration direction (Xh, Yh, Zh), grip force (25-75 N), feed force (20-60 N), frequency weighted acceleration level (3, 6, 9, 12 m/s2) and hand and arm posture (5 flexions, 2 abductions) were studied. The outcome showed that the energy absorption in the human hand and arm depended mainly on the frequency and direction of the vibration stimuli. Higher vibration levels, as well as firmer hand grips and higher feed forces, resulted in a significantly higher absorption. As concerns the hand and arm posture the results show that the flexion had a significant contribution to the vibration absorption but the abduction had no influence on the quantity of absorbed energy. Furthermore, the influence of some of the studied variables had a non-linear effect on the absorption but also differed between different exposure directions. Moreover, it was concluded that the frequency-weighting routine in the international standard ISO 5349 do not reflect the energy absorbing properties of the human hand and arm.
Abstracts
Annual Research Meeting for Graduate Students: Nagoya, December 1993
pg(s)169-198
< PDF >