[A clinico-pathological study on the mucosal heights of superficial type (type II) early colon cancer].
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Adenocarcinoma↗
Biomedical subjects
T Fujimori
Publications and source records attributed to T Fujimori.
Lanthanum inhibits steady-state turnover of the sarcoplasmic reticulum calcium ATPase by replacing magnesium as the catalytic ion.
LaATP is shown to be an effective inhibitor of the calcium ATPase of sarcoplasmic reticulum because the binding of LaATP to cE.Ca2 results in the formation of lanthanum phosphoenzyme, which decays slowly. Steady-state activity of the calcium ATPase in leaky sarcoplasmic reticulum vesicles is inhibited 50% by 0.16 microM LaCl3 (15 nM free La3+, 21 nM LaATP) in the presence of 25 microM Ca2+ and 49 microM MgATP (5 mM MgSO4, 100 mM KCl, 40 mM 4-morpholinepropanesulfonic acid, pH 7.0, 25 degrees C). However, 50% inhibition of the uptake of 45Ca and phosphorylation by [gamma-32P]ATP in a single turnover experiment requires 100 microM LaCl3 (28 microM free La3+) in the presence of 25 microM Ca2+; this inhibition is reversed by calcium but inhibition of steady-state turnover is not. Therefore, binding of La3+ to the cytoplasmic calcium transport site is not responsible for the inhibition of steady-state ATPase activity. The addition of 6.7 microM LaCl3 (1.1 microM free La3+) has no effect on the rate of dephosphorylation of phosphoenzyme formed from MgATP and enzyme in leaky vesicles, while 6.7 mM CaCl2 slows the rate of phosphoenzyme hydrolysis as expected; 6.7 microM LaCl3 and 6.7 mM CaCl2 cause 95 and 98% inhibition of steady-state ATPase activity, respectively. This shows that inhibition of ATPase activity in the steady state is not caused by binding of La3+ to the intravesicular calcium transport site of the phosphoenzyme. Inhibition of ATPase activity by 2 microM LaCl3 (0.16 microM free La3+, 0.31 microM LaATP) requires greater than 5 s, which corresponds to approximately 50 turnovers, to reach a steady-state level of greater than or equal to 80% inhibition. Inhibition by La3+ is fully reversed by the addition of 0.55 mM CaCl2 and 0.50 mM EGTA; this reactivation is slow with t1/2 approximately 9 s. Two forms of phosphoenzyme are present in reactions that are partially inhibited by La3+: phosphoenzyme with Mg2+ at the catalytic site and phosphoenzyme with La3+ at the catalytic site, which undergo hydrolysis with observed rate constants of greater than 4 and 0.05 s-1, respectively. We conclude, therefore, that La3+ inhibits steady-state ATPase activity under these conditions by replacing Mg2+ as the catalytic ion for phosphoryl transfer. The slow development of inhibition corresponds to the accumulation of lanthanum phosphoenzyme. Initially, most of the enzyme catalyzes MgATP hydrolysis, but the fraction of enzyme with La3+ bound to the catalytic site gradually increases because lanthanum phosphoenzyme undergoes hydrolysis much more slowly than does magnesium phosphoenzyme.(ABSTRACT TRUNCATED AT 400 WORDS)
Adenosine Triphosphate↗
Photodynamic therapy for early gastric cancer using a pulsed gold vapor laser.
Endoscopic photodynamic therapy (PDT) using a pulsed gold vapor laser (wavelength 628 nm, LaserSonics Inc.) was performed on eight cases of early gastric cancer. Three patients refused to have surgery, and the others were in a high-risk group due to old age or complications with other diseases. Hematoporphyrin derivative (HpD I, 2.5-3 mg/kg, Photofrin Inc.) was injected intravenously, and 48-72 hours later, the entire cancer lesion and 5 mm width mucosa encircling it were irradiated with a gold vapor laser through a single quartz fiber. The irradiation was delivered at 300-330 mW for 5-20 minutes, which gave about 90 J/cm 2 dosage. In seven of eight cases, local cure was achieved. Recurrence was noted only in one patient. In one of eight patients, operation was carried out 1 month after PDT. Pathological examination of the resected stomach revealed that the effect of PDT extended into the tunica muscularis propria. Side effects of HpD, such as skin rash, were noted in two patients, but no serious complications of PDT were encountered. This suggests that PDT with a pulsed gold vapor laser is clinically useful in the treatment of early gastric cancer.
Adult↗
Monoclonal antibodies to disialogangliosides: characterization of antibody-mediated cytotoxicity against human melanoma and neuroblastoma cells in vitro.
We previously reported the binding specificities of two anti-ganglioside GD2 murine monoclonal antibodies (MAbs), A1-425 and A1-267, both of which are of IgG3 isotype. A1-425 reacts specifically with ganglioside GD2, whereas A1-267 binds preferentially to GD2 but also reacts with GD3 [Tai, T., Kawashima, I., Tada, N., & Dairiki, K. (1988) J. Biochem. 103, 682-687]. In this paper, they were used for comparative analyses of antibody-mediated cytotoxicity, i.e., antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) against human melanoma and neuroblastoma cell lines. Melanoma cells were found to contain GD2 and/or GD3, whereas neuroblastoma cells expressed only GD2. Both antibodies induced high levels of ADCC and CDC to GD2/GD3-positive cells with human peripheral large granular lymphocytes (LGL) as effector cells and in the presence of human serum, respectively. A good correlation was obtained between the contents of disialogangliosides and the binding level of the antibodies; both melanoma and neuroblastoma cells with larger amounts of GD2/GD3 showed a higher level of antibody binding than did the cells with a smaller amount of GD2/GD3. Surprisingly, ADCC did not correlate well with the binding level of the antibodies. Thus, A1-425 showed stronger lytic activity than A1-267 in spite of the binding level of A1-425 being similar to or lower than that of A1-267 on the cell surfaces. Antigen-antibody complexes composed of GD2 and A1-425 showed higher binding levels to LGL than complexes of GD2 and A1-267. In contrast, free MAb molecules gave minimum binding to LGL.(ABSTRACT TRUNCATED AT 250 WORDS)
Animals↗
Inhibitory effects of a novel antiplatelet aggregating agent, E-5510, on cyclic flow variations in electrically stimulated coronary arteries of the pig.
We examined the inhibitory effects of a novel antiplatelet aggregating agent, E-5510, on cyclic flow variations (CFVs) of coronary blood flow (CBF) in anesthetized open-chest pigs. These CFVs, which are characterized by progressive declines in CBF followed by sudden restoration of flow, were initiated by electrical stimulation of the intimal surface of the left circumflex coronary artery (LCX). A reduction in CBF to zero during CFVs was accompanied by ischemic changes in the surface electrocardiogram and regional segment shortening of the left ventricular wall. Occlusive thrombi were detected postmortem in the coronary arteries of the animals in which CFVs had occurred. After CFVs had been observed for 1 h, E-5510 (0.01 or 0.1 mg/kg) or saline was administered intravenously. Once CFVs were initiated, both the frequency and the severity (the mean of the three lowest nadirs of CBF) were unchanged by the administration of saline. E-5510 at 0.01 mg/kg decreased the frequency of CFVs from 7.7 +/- 0.9 to 4.6 +/- 1.1 CFV s/h (n = 7, p less than 0.05), and increased the mean lowest nadir from 13.5 +/- 5.2% of the CBF level before electrical stimulation to 54.3 +/- 11.1% (n = 7, p less than 0.01). E-5510 at 0.1 mg/kg further decreased the frequency from 8.9 +/- 0.7 to 2.4 +/- 0.5 CFVs/h (n = 9, p less than 0.01), and increased the mean lowest nadir from 14.3 +/- 3.2% to 53.6 +/- 10.8% (n = 9, p less than 0.01). E-5510, however, showed no ameliorative effect on ischemia-induced myocardial dysfunction, as expressed by the decrease in regional myocardial shortening.(ABSTRACT TRUNCATED AT 250 WORDS)
Animals↗
Cadherin subclasses: differential expression and their roles in neural morphogenesis.
Cadherins homophilically bind cells. Thus, cells expressing identical cadherins adhere selectively to each other, and they do not randomly intermix with the cells expressing other types of cadherins in vitro. Neural tissues express multiple types of cadherins, and the expression of each cadherin type is spatiotemporally regulated within a tissue during development. This molecular family therefore could operate for the sorting of different cell types in the nervous system. The regulation of N-cadherin expression is also important for the early development of the neural tube. The ectopic expression of N-cadherin in Xenopus embryos, which was induced by mRNA injection, led to the disorganization of neural tube structures or the fusion of the neural tube to the epidermis. These results suggest that the precise regulation of cadherin expression at the quantitative as well as at the qualitative level si crucial for neural morphogenesis.
Animals↗
Ectopic expression of N-cadherin perturbs histogenesis in Xenopus embryos.
Xenopus embryos express N-cadherin in a pattern similar to that observed in other species, and cells expressing Xenopus N-cadherin can bind to cells expressing chicken N-cadherin in vitro. To investigate the developmental role of this molecule, we injected mRNA encoding chicken N-cadherin into one blastomere of 2-cell-stage Xenopus embryos and examined the effect of its expression on their development. The ectopic expression of N-cadherin occurred in various regions of the injected embryos and induced abnormal histogenesis, such as thickening, clumping or fusion of cell layers. These results suggest that the precise quantitative and qualitative regulation of the expression of cadherins is essential to embryonic morphogenesis.
Animals↗
Value of tissue carcinoembryonic antigen in patients with colorectal carcinoma.
The tumours of 55 patients with colorectal carcinoma were evaluated for tissue carcinoembryonic antigen (CEA) by immunoperoxidase staining. It was shown that 33/35 patients with increased preoperative serum CEA levels above 5 ng/ml had positive tissue CEA. The other 17/20 patients who had serum CEA levels less than 5 ng/ml could be demonstrated CEA in tissue. The results of tissues CEA were compared with their preoperative serum CEA levels in the pathologic grading, histologic type and staging of cancer. It was found that tissue CEA was more sensitive than serum CEA and was correlated with serum CEA in all respects. The finding in this study suggests that tissue CEA should be performed along with preoperative serum CEA in all patients suspected of having colorectal carcinoma. The postoperative serum CEA should be determined serially in the patients who have more than 5 ng/ml serum CEA and/or tissue CEA positive although their preoperative serum CEA is less than 5 ng/ml.
Adenocarcinoma↗
[An autopsy case of extramural malignant leiomyoblastoma of the stomach with ovarian cancer: an immunohistochemical study].
The subject was an 85-year-old woman, who had been diagnosed as having an ovarian cancer and carcinomatous peritonitis and had been treated conservatively. She subsequently died from respiratory and renal insufficiency, and the autopsy that followed revealed that her pelvic cavity had been filled by a tumorous mass that size of a child's head. Histologically, the tumor was a serous cystadenocarcinoma of the ovary. Moreover another tumor, also the approximate size of a child's head, was found sited extramurally, beneath the posterior wall mucosa of the stomach body. Histological inspection of this tumor revealed a proliferation of round oval, and spindle-shaped tumor cells. A vacuolation of the cytoplasms and karyomitosis to the extent of 10/50 HPF also were observed. Based on the findings of being positive for Vimentin and a negative EMA, this tumor was diagnosed as being a malignant leiomyoblastoma of the stomach smooth muscle. The leioblastoma is a relatively uncommon neoplasm, and recent advances in immunohistochemical staining have indicated that some of these tumors are not only of smooth muscle derivation but also of nerve origin. Therefore, this tumor, given its morphological characteristics, had been generalized in this case as a gastric stromal tumor, and with negative findings for Desmin and S-100 protein, as well as positive for Vimentin.
Aged↗
[Clinicopathological and immunohistochemical study on penetrating and superficial spreading type of early gastric cancers].
Specific type of early gastric cancer based on the cancer surface area and the degree of invasion were studied by measuring digital values of the cancer surface area in early gastric cancer patients. The results indicated that the pen and super type of early gastric cancer had many clinicopathological characteristics as compared with common type of early gastric cancer. An immunohistochemical study also revealed that the pen type of early gastric cancer had a high growth activity. Moreover, it was suggested that EGF was involved in its specific invasion and growth, and that EGF and TGF-beta affected its scirrhous growth. The possibility that the poorly differentiated pen type is an early lesion of linitis plastica type gastric cancer was also considered. From these findings, it was assumed that the immunological staining of EGF and TGF-beta in biopsy specimens might be useful in the diagnosis of the pen type of early gastric cancer and also in diagnosis of early lesion of linitis plastica type gastric cancer.
Epidermal Growth Factor↗
Mouse Ly-31.1 is an alloantigenic determinant of alkaline phosphatase predominantly expressed in the kidney and bone.
The mouse lymphocyte surface alloantigen, Ly-31, defined by monoclonal antibody N1.10 (IgG2b,k) and controlled by a gene locus closely linked to the Akp-2 locus on chromosome 4, was biochemically investigated. By employing a quantitative immunoassay system, it was found that the Ly-31.1-specific antibody detected an allotypic determinant of mouse alkaline phosphatase. Ly-31.1, i.e., mouse alkaline phosphatase, was expressed predominantly in kidney and bone and was also detected in placenta, lung, and testis. Concerning tumor cell lines, they varied in the amount of antigen present, with both T and B lymphoid lineages selectively possessing the antigen. In normal lymphoid tissues, lesser amounts of antigen were detected. The binding of mouse alkaline phosphatase to Ly-31.1-specific monoclonal antibodies was specific in nature. The Ly-31.1 antigen was immunoprecipitated from the lysates of surface-radiolabeled YAC-1 moloney leukemia cells, and appeared as a single band of about 78,000 under both reduced and nonreduced conditions on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Furthermore, treatment of tumor cell lines with phosphatidylinositol-specific-phospholipase C resulted in the removal of Ly-31 antigen from the cell surface. These results suggest that a gene cluster containing the Ly-31 and Akp-2 loci which control the alkaline phosphatase is formed on mouse chromosome 4. The Ly-31 antigen is the first enzyme demonstrated to be a lymphocyte surface alloantigen.
Alkaline Phosphatase↗
[Monoclonal antibody to desmosome associated 34 kD protein and immunohistochemical study in relation to the malignancy of transitional cell carcinomas of urinary bladder].
A mouse monoclonal IgG1 antibody (B-11) that recognized desmosomes in some human tissues was isolated and characterized. By Western blotting, B-11 recognized 34 kD protein only in squamous and transitional epithelium. By avidin-biotin complex (ABC) and immunofluorescence method, B-11 was reactive to squamous and transitional epithelium, but was not reactive to simple columnar epithelium from stomach and colon, simple cuboidal epithelium from urinary tubule and thyroid, and pseudostratified ciliated epithelium from trachea and ductus epididymidis. ABC method of B-11 was performed in 47 patients with transitional cell carcinoma of bladder. The higher positive staining was observed in well differentiated (83% in Grade (G) 1, 73% in G2 and 20% in G3), superficial (76% in non-invasive and 20% in invasive) and expansive growth (68% in Infiltration (INF) alpha, 24% in IFN beta and 18% in IFN gamma) carcinomas. 34 kD protein recognized by a new monoclonal antibody (B-11) is a new cell-type-specific desmosomal component which relates to the histological grade, stage and invasive manner of the transitional cell carcinoma of bladder. The transitional cell carcinoma of bladder obtained by operation or surgical biopsy from 47 patients was stained by ABC method using B-11.
Adult↗
Biochemical similarity of Ly-19, Ly-32, and Lyb-2 alloantigens encoded in the gene cluster on mouse chromosome 4.
Mouse lymphocyte alloantigens Ly-19 and Ly-32 are controlled by the genes tightly linked to the Lyb-2 locus on chromosome 4. Despite the similarity in mouse strain distribution patterns, Ly-19 and Ly-32 antigens which have been detected on both B- and T-cell lineages are distinct from Lyb-2 antigen whose expression is restricted to the B cells. In this report, the close linkage of these three loci was confirmed by the typings of three sets of recombinant inbred mice including BXD, CXS, and OXA. Furthermore, the biochemical characterization of these Lyb-2-linked proteins, i.e., Ly-19, Ly-32, and Lyb-2, demonstrated their similarities on a molecular level. Two polypeptides of 45,000 and 95,000 were the components of these three alloantigens. Furthermore, sequential immunoprecipitation experiments indicated that the three alloantigenic determinants were located on the same molecular components. These findings may provide insight into the complexities and functional roles of Lyb-2 gene-cluster products.
Animals↗
Relationship between mouse Ly-2 and the Mus musculus molossinus-specific Ly-35 alloantigenic determinants.
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Alleles↗
Ly-36: a new mouse lymphocyte alloantigen defined by a Mus musculus molossinus-specific monoclonal antibody and controlled by a gene linked to Ly-2/3 region on chromosome 6.
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Animals↗
A new mouse lymphocyte alloantigen (Ly-35) controlled by the Ly-2/3 region on chromosome 6.
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Animals↗
Extracellular calcium protects cultured rat hepatocytes from injury caused by hypothermic preservation.
Effects of various preservation solutions were compared in an experimental hypothermic preservation model using cultured rat hepatocytes. Hepatocytes prepared by the collagenase perfusion method were cultured for 48 hr, then the medium in each culture dish was exchanged for various preservation solutions, and the dishes were hypothermically (0-2 degrees C) stored in a refrigerator for 12-72 hr. After the preservation period, the hepatocytes were cultured again at 37 degrees C for 2 hr. Hepatocytes' viability after 18-hr preservation and reculture was greater when they were preserved in "intracellular" rather than "extracellular" solutions. Even with Euro-Collins solution (intracellular solution), hepatocyte viability decreased to approximately 20% after 24-hr preservation, and an increase in the cellular lipid peroxide content was observed. However, when this solution contained a submillimolar concentration of calcium, lipid peroxidation was significantly suppressed and hepatocyte viability was dramatically improved. Vitamin E was almost equally effective and a marked synergistic effect was observed with calcium. Calcium was found to be capable of maintaining the cellular glutathione level during cold storage, which seems to suppress lipid peroxidation and consequently improve hepatocyte survival.
Animals↗
Cross-bridge kinetics, cooperativity, and negatively strained cross-bridges in vertebrate smooth muscle. A laser-flash photolysis study.
The effects of laser-flash photolytic release of ATP from caged ATP [P3-1(2-nitrophenyl)ethyladenosine-5'-triphosphate] on stiffness and tension transients were studied in permeabilized guinea pig protal vein smooth muscle. During rigor, induced by removing ATP from the relaxed or contracting muscles, stiffness was greater than in relaxed muscle, and electron microscopy showed cross-bridges attached to actin filaments at an approximately 45 degree angle. In the absence of Ca2+, liberation of ATP (0.1-1 mM) into muscles in rigor caused relaxation, with kinetics indicating cooperative reattachment of some cross-bridges. Inorganic phosphate (Pi; 20 mM) accelerated relaxation. A rapid phase of force development, accompanied by a decline in stiffness and unaffected by 20 mM Pi, was observed upon liberation of ATP in muscles that were released by 0.5-1.0% just before the laser pulse. This force increment observed upon detachment suggests that the cross-bridges can bear a negative tension. The second-order rate constant for detachment of rigor cross-bridges by ATP, in the absence of Ca2+, was estimated to be 0.1-2.5 X 10(5) M-1s-1, which indicates that this reaction is too fast to limit the rate of ATP hydrolysis during physiological contractions. In the presence of Ca2+, force development occurred at a rate (0.4 s-1) similar to that of intact, electrically stimulated tissue. The rate of force development was an order of magnitude faster in muscles that had been thiophosphorylated with ATP gamma S before the photochemical liberation of ATP, which indicates that under physiological conditions, in non-thiophosphorylated muscles, light-chain phosphorylation, rather than intrinsic properties of the actomyosin cross-bridges, limits the rate of force development. The release of micromolar ATP or CTP from caged ATP or caged CTP caused force development of up to 40% of maximal active tension in the absence of Ca2+, consistent with cooperative attachment of cross-bridges. Cooperative reattachment of dephosphorylated cross-bridges may contribute to force maintenance at low energy cost and low cross-bridge cycling rates in smooth muscle.
Actomyosin↗