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K Kojima

Publications and source records attributed to K Kojima.

At least 505 records · Page 28Linked to original sources
PubMed1990

[Clinico-pathological studies on Is, Ip polyps and flat elevations in the large intestine].

We histologically compared 3 types of adenoma and cancer of the large intestine using 620 adenoma specimens (509 Is type lesions, 83 Ip type lesions, and 28 flat type lesions) and 113 specimens of early stage cancer (51 Is type lesions, 39 Ip type lesions, and 23 flat type lesions) obtained during the past 5-year period at our department. More than 90% of the Is and Ip type polyps were adenoma or carcinoma in adenoma while 25.5% of the flat elevations were m or sm carcinoma. Flat elevations even less than 10 mm in diameter were frequently carcinomas (26.3%) compared with the other types (both Is and Ip types, 6.7%), and all of those 10 mm or more in size were carcinomas. The distribution of the flat type early cancers in the large intestine was similar to that of advanced cancer with high percentages of carcinoma at each site compared with the other types. These results suggest that the carcinogenesis and progression of flat type early stage cancer differ from those of the other types.

Adenoma↗
PubMed1990

[Application of lectin histochemistry to various types of corneal dystrophy].

We described the staining pattern of deposits in 4 cases of the staining method employing corneal dystrophy by avidin-biotin peroxidase complex employing biotinated lectins as intermediate products. The specimens consisted of 8 keratoplasty specimens obtained from 2 cases of granular dystrophy and 4 cases of lattice dystrophy and one case each of primary droplet dystrophy and Reis-Bücklers dystrophy. In two cases with granular dystrophy, deposits stained positively with WGA and with Con A in one case. The deposits found in lattice dystrophy were stained with WGA in 3 cases and with Con A in one case. The deposits noted in primary gelatinous droplet dystrophy were stained with WGA and those in Reis-Bücklers dystrophy were not stained with any lectin. The staining patterns suggested that the deposits found in granular and lattice dystrophy possess N-acetyl-D-glucosamine as a sugar residue. They may possess alpha-D-mannose and/or alpha-D-glucose.

Acetylglucosamine↗
PubMed1990

[Transcatheter arterial embolization for massive abdominal bleeding in post-pancreatoduodenectomy--first report].

Transcatheter arteria embolization (TAE) was carried out for 10 cases (14 times) with massive intra-abdominal bleeding after pancreatoduodenectomy (PD). The results obtained were as follows: 1. The ten patients (carcinoma of the pancreas head 4, carcinoma of the papilla Vater: 3, carcinoma of the bile duct: 2. leiomyosarcoma of the duodenum: 1) included eight men and two women aged 45 to 75, with an average age of 63.7. The time span before TAE was instituted averaged 20.8 days. 2. Infection due to leakage noted in all cases. 3. A good course was noted when manifestation of symptoms related to poor sutures or the onset of intra-abdominal bleeding after PD was delayed and the time from the onset of intra-abdominal bleeding to TAE was short. 4. Bleeding sites could be determined in all cases. Pseudoaneurysm accounted for five and extravasation accounted for nine of the total of 14 bleeding sites. The prognosis was apparently good in cases of pseudoaneurysm as compared with that in cases of extravasation. 5. Bleeding was controlled in all cases. 6. No complication due to TAE occurred. These results indicate the TAE is a safe and effective procedure for the control of massive intra-abdominal bleeding after PD.

Abdomen↗
PubMed1989

Human monoclonal antibody (HMST-1) against lacto-series type 1 chain and expression of the chain in uterine endometrial cancers.

A human monoclonal antibody termed HMST-1 was produced by fusing lymphocytes from segments of human pelvic lymph nodes from an endometrial cancer patient with murine myeloma cells. The epitope recognized by HMST-1 was determined to be lacto-series type 1 chain-containing glycosphingolipid (Gal beta 1-3GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1Cer) by isolating the antigen from endometrial cancer cell line SNG-II and analyzing with fast atom bombardment mass spectrometry, permethylation analysis, and exoglycosidase treatment. By the immunohistochemical avidin-biotin-peroxidase complex method, no normal endometrium and benign endometrial hyperplasia were stained with HMST-1, but HMST-1 reacted with about 35% of endometrial cancer cases. These facts indicate that the rate of expression of the antigen increases along with the course of malignancy in the endometrium. By sialidase treatment of the section, the positive rate increased to 57% in endometrial cancers and to 13% in normal endometrium, indicating that the antigen was masked with sialic acid and exposed by neuraminidase treatment. Immunohistochemistry also revealed that the antibody reacted with human fetal alimentary tract epithelium and mesothelium, indicating the oncodevelopmental nature of Gal beta 1-3GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1Cer.

Antibodies, Monoclonal↗
PubMed1989

Beta 2-microglobulin decrease in cerebrospinal fluid from parkinsonian patients.

A sandwich enzyme immunoassay (EIA) was established by using purified beta 2-microglobulin (beta 2-MG) as a standard protein and a polyclonal antibody raised against human beta 2-MG. The EIA was applied for the measurement of beta 2-MG levels in human cerebrospinal fluid (CSF) from parkinsonian patients and control patients devoid of neurological diseases. beta 2-MG contents in CSF of the control group and the parkinsonian group were 1.81 +/- 0.11 micrograms/ml CSF and 0.63 +/- 0.09 microgram/ml CSF, respectively. Thus, beta 2-MG content in CSF was reduced in parkinsonian patients to less than 35% of the control value (P less than 0.005). We had previously reported that the activity and content of dopamine beta-hydroxylase (DBH) were decreased in CSF from parkinsonian patients. A significant positive correlation (r = 0.87) was observed between the beta 2-MG content and DBH activity for CSF from 45 patients. These results suggest a probable link between an immunological change and the changes in catecholaminergic neurons in Parkinson's disease.

Adult↗
PubMed1989

A novel phospholipase A2 associated with nuclear matrix: stimulation of the activity and modulation of the Ca2+ dependency by polyphosphoinositides.

Neutral phospholipase A2 activity, which hydrolyzed phosphatidylcholine and phosphatidylethanolamine with the same efficiency, was identified in the nuclear matrix prepared from purified nuclei of rat ascites hepatoma cells (AH 7974). The enzyme activity was optimal at pH 7.0 and required Ca2+ absolutely. Concentrations of Ca2+ for a maximal and a half-maximal activation were 1.10(-2) and 1.10(-3) M, respectively, and little activity was detected at Ca2+ concentrations lower than 1.10(-5) M. Addition of acidic phospholipids markedly stimulated the enzyme activity, and further, lowered the minimum Ca2+ concentration required for activation. In particular, the polyphosphoionositides phosphatidylinositol 4-monophosphate and 4,5-diphosphate were most effective. These two polyphosphoinositides lowered the Ca2+ concentration required for half-maximal activation to 10(-5) M and dramatically stimulated the activity at that Ca2+ concentration (greater than 30-fold). The neutral phospholipase A2 activity such as characterized in the present study was very low in the other subcellular fractions including mitochondria, microsome, plasma membrane and cytosol.

Animals↗
PubMed1989

[Ultrasonographic diagnosis of mild fatty infiltration of the liver with the difference between liver and kidney echolevels].

At the same dynamic range (DR) a constant difference of echolevels was found between two materials with different acoustic impedance in any gain-setting by the phantom study. Our retrospective study in which we compared the difference between liver-kidney echolevels with the US-findings of fatty liver indicated that the difference over 10 in echoleveled by our equipment with 3.5 MHz phased array sector scan and 42 dB DR had a possibility of the fatty infiltration of the live. In our prospective study of 1452 abdominal US-studies we found 93 cases (6.5%) with the difference over 10 in echolevel. In all these patients the difference of liver-spleen CT-numbers and liver-kidney echolevels was compared. Although the liver CT-number is normally higher than the spleen, 75 of 93 patients showed the lower liver CT-number than that of the spleen, indicating fatty infiltration of the liver. The abnormal difference of echolevels were independent from the severity of fatty infiltration. Concerning the US-findings, "bright liver" (77.4%) and "masking sign" (66.7%) were more sensitive than "vascular blurring" (44.1%) and "deep attenuation" (44.1%). But for the severe fatty infiltration with the difference over -20 H.U. between liver-spleen CT numbers, the last two findings seemed very credible. The abnormal difference between liver-kidney echolevels was most sensitive (80.7%), especially in mild cases with 0 to -19 H.U. (53 in 75 cases), and very objective than the other US-findings.

Fatty Liver↗
PubMed1989

Interaction of DNA polymerases with phospholipids.

Effects of various phospholipids on the in vitro reactions of eukaryotic DNA polymerases alpha, beta and gamma were tested systematically. When phospholipids were added directly to the reaction mixture, neither stimulation nor inhibition was produced. However, when phospholipids were preincubated with enzymes in the absence of template-primer, some of them showed strong inhibition. Cardiolipin strongly inhibited the reactions of all three DNA polymerases and also of terminal deoxynucleotidyl transferase. Phosphatidylinositol selectively inhibited the reaction of DNA polymerase gamma. Phosphatidic acid moderately inhibited DNA polymerase alpha and strongly inhibited DNA polymerase gamma. The inhibition of DNA polymerase gamma by cardiolipin was nearly competitive with template-primer. Since the inhibition was reversed by the addition of 0.05% Triton-X 100 during preincubation, the phospholipid might interact with enzyme protein at the hydrophobic region in competition with template-primer. These results suggest a possible involvement of phospholipids in DNA replication in mitochondria and in nucleus through interaction with DNA polymerase.

Cardiolipins↗
PubMed1989

Tumor-associated mucin-type glycoprotein (CA54/61) defined by two monoclonal antibodies (MA54 and MA61) in ovarian cancers.

Two monoclonal antibodies, MA54 and MA61, were established by immunizing with culture medium supernatants of a lung adenocarcinoma cell line, and a double-determinant sandwich enzyme immunoassay system was developed by using these two monoclonal antibodies. The antigen recognized by this assay (CA54/61) was found to be often high in the sera of several cancers. The antigen recognized by MA54 (CA54) or MA61 (CA61) proved to be carbohydrate chain on a high molecular weight mucin-type glycoprotein, and CA54 has NeuAc alpha 2-6galactose in the terminal residue. CA54/61 was frequently found in the sera of ovarian cancer patients, the positive rate being 67, 64, 40, and 78% in serous, mucinous, endometrioid, and mesonephroid cancers, respectively, when the cut off value was set at mean + 4 SD. Since the positive rate of CA125, which is now the most widely used for the diagnosis of ovarian cancers, is rather low (approximately less than 50%) in mucinous cystoadenocarcinoma, CA54/61 will be of clinical value. In addition, CA61 was detected immunohistochemically in the fetal red blood cells with nuclei, indicating its oncodevelopmental character in nature.

Antibodies, Monoclonal↗
PubMed1989

Possible roles of cAMP and Ca2+ in the regulation of miracidial transformation in Schistosoma mansoni.

The triggering action of physiological saline in the miracidial transformation of Schistosoma mansoni was analyzed using various agents affecting cAMP- and Ca2+-dependent pathways. Potent activators of adenylate cyclase, such as forskolin and serotonin, strongly inhibited the transformation provoked by saline in RPMI-1640. These inhibitory actions were diminished by the combined administration of phosphodiesterase activators such as ammonium salts or imidazole. Furthermore, the exposure of miracidia to ammonium salts or imidazole in dechlorinated tap water "mimicked" the transformation, i.e., the cessation, of swimming and then shedding of epithelial plates. This mimic transformation was also inhibited by serotonin or forskolin. In contrast, treatment of miracidia with Ca2+ antagonists such as TMB-8 (an inhibitor of Ca2+ release), nicardipine (a Ca2+ channel blocker), or W-7 (a calmodulin inhibitor) in tap water produced severe vesiculation on their body surfaces and resulted in death. However, these toxic effects were abolished by a combined administration of these Ca2+ antagonists with saline or NH4Cl, and the transformation was reestablished except with W-7 treatment. W-7 strongly inhibited the triggering action of saline and NH4Cl and the worms swam slowly, whereas W-5, an inactive analogue of W-7, had no inhibitory effect on the transformation. These results suggest that the initiation of micracidial transformation to young sporocysts may be synergistically regulated by cAMP and Ca2+ and that a decrease in cAMP levels and an increase in Ca2+ mobilization may be provoked in worms transformed by saline, ammonium salts, or imidazole.

Animals↗
PubMed1989

A kinetic study on secretion and elimination of endogenous thyrotropin in the thyrotropin-releasing hormone test.

Serum thyrotropin (TSH) concentrations in normal young men were measured by a high-sensitivity immunoradiometric assay before and after intravenous administration of 500 micrograms of TSH-releasing hormone (TRH). A kinetic model was applied to evaluate the secretion rate both before (V0) and after (V0 + V* at maximum rate) the administration of TRH, the elimination constant (K), the latent time (L) between TRH administration and start of the stimulated secretion, and the total amount of TSH (T) released in response to TRH. V0, V* and T varied widely from individual to individual, but correlated well with TSH before TRH administration (r = 0.93, 0.80 and 0.87, respectively). A few minutes (1.89 +/- 1.30 min) after the administration of TRH, the secretion of TSH (0.025 +/- 0.016 microU/min ml) was stimulated, and the total release over about 1 h was 12.5 +/- 5.6 microU/ml. Serum TSH was maximum at 31.5 +/- 5.7 min. The half-time of disappearance of TSH was 42 +/- 9 min. These data confirm that the stimulated secretion continues for more than 30 min, and that the pituitary releases 43.2 +/- 22.9 mU of TSH (assuming the distribution volume of TSH is 5.8% of body weight) in response to TRH, an amount which correlates closely (r = 0.91) with TSH before TRH administration.

Adult↗
PubMed1989

Clinical values for an index predicting postoperative residual liver function by pre-operative liver-scintigraphy in patients with liver disease.

Hepatic resection is essential in treating hepatocellular carcinoma. However, before an operation, it is difficult to predict the functional reserve in the remnant following massive resection. We devised an original method by which effective liver volume was measured by liver scintigraphy. In order to predict the residual liver function before hepatic resection in a preoperative radiocolloid study, we obtained a predictive index by combining the K values with effective liver volumes which seemed to have the estimated residual liver function. Twenty-one patients with liver or biliary tract disease were selected at random for the present study. We divided them into 3 groups in accordance with prognosis after hepatic resection. There were statistically significant difference between the deceased group who died from hepatic failure and the group who died from causes other than hepatic failure; and between the deceased group who died from hepatic failure and the living group in the preictive index (p less than 0.01). Our data suggest that if the predictive index is above 0.45, the probability of hepatic failure after hepatic resection is low. We concluded that our predictive index is useful to use in preoperative prediction of post-hepatectomic residual liver function.

Aged↗
PubMed1989

Menstrual cycle-associated alteration of sulfogalactosylceramide in human uterine endometrium: possible induction of glycolipid sulfation by sex steroid hormones.

The human uterine endometrium is a tissue in which cell proliferation and differentiation are strictly controlled by sex steroid hormones, and these hormone-controlled cellular events occurring in association with the menstrual cycle of the uterine endometrium should be accompanied by characteristic molecular and metabolic changes. To characterize the menstrual cycle at the molecular level, we analyzed the glycolipids of human uterine endometrium in the proliferative and secretory phases of the menstrual cycle. Neutral glycosphingolipids from uterine endometrium comprised globo-series glycosphingolipids, such as GlcCer, LacCer, Gb3Cer, and Gb4Cer, and the relative concentrations remained constant in the two phases. However, in the case of acidic glycosphingolipids, although the concentrations of sialoglycosphingolipids remained at constant levels in the two phases, sulfatide, I3-SulfoGalCer, dramatically increased from the proliferative to the secretory phase, amounting to 7-17 nmol/g dry weight in the proliferative phase and 115-245 nmol/g dry weight in the secretory phase. Since sulfatide was the only glycolipid that changed in association with the menstrual cycle, it is likely that the sulfotransferase responsible for the synthesis of sulfatide might be induced by sex steroid hormones, estrogen and progesterone, and that sulfatide might play an essential biological role in the secretory phase of the menstrual cycle in the uterine endometrium.

Cerebrosides↗
PubMed1989

An automated optoelectronic reticulocyte counter.

Microscopic reticulocyte counting is time consuming and imprecise. A new reticulocyte counter has been developed, and the authors evaluated its utility for laboratory use. The counter, R-1000 of Sysmex-TOA Medical Electronics Company, Kobe, Japan, is based on the principles of flow cytometry. Reticulocytes are detected as fluorescent cells stained with a basic dye, auramine O, under argon-laser light. The automated count had high correlation to the manual count (r = 0.941). Linearity and reproducibility were both high. About 60 specimens were tested in one hour. Not only the reticulocyte percentage and count but also the maturity of reticulocytes was found from the intensity of the fluorescence, whether high, moderate, or slight. Normal reference values were 0.007 +/- 0.0055 (0.70 +/- 0.55%) for the reticulocytes, (4.63 +/- 1.09) X 10(9)/L for the reticulocyte count, 2.3 +/- 1.9% for highly fluorescent cells, 18.7 +/- 5.1% for moderately fluorescent cells, and 78.8 +/- 6.6% for cells with slight fluorescence. In patients with suppressed bone marrow function, such as is caused by chemotherapy, the reticulocyte fraction and count were low, and cells with slight fluorescence increased. In patients in whom bone marrow function was stimulated, such as with hemolytic anemia, the reticulocyte percentage, reticulocyte count, and highly fluorescent cells were high. Patients with chronic renal failure being treated by hemodialysis had a similar reticulocyte pattern to that in hemolytic anemia except that the reticulocyte count was decreased. Results for elderly patients were not different from those of healthy young controls. Some patients with a normal reticulocyte count and percentage had numerous highly fluorescent cells, perhaps because of hemolytic anemia not yet identified. Automated reticulocyte counting provides reliable data, so such measurement should be useful for analysis of the kinetics of red blood cells and for the study of the pathogenesis of anemia.

Adult↗
PubMed1989

A novel stimulating protein of mammalian DNA polymerase alpha.

A DNA polymerase alpha-primase complex, which had been purified by means of immunoaffinity column chromatography, showed little activity in a reaction mixture composed of Tris-HCl buffer, but showed full activity in potassium phosphate buffer. It was found that potassium ion is required for the reaction by the immunoaffinity-purified enzyme. On the other hand, the DNA polymerase alpha purified by the orthodox biochemical method showed full activity in both buffer systems. A protein factor, which could restore the activity of immunoaffinity-purified DNA polymerase alpha-primase complex in the potassium-free reaction mixture, was separated from biochemically purified DNA polymerase alpha. The factor, designated as factor T, was stable to heat up to 70 degrees C, but was sensitive to trypsin. It sedimented at about 4S through a glycerol gradient. SDS-polyacrylamide gel electrophoresis revealed two polypeptide bands at 56 and 54 kDa. By immunoprecipitation, the factor T was shown to be physically associated with DNA polymerase alpha-primase complex. The stimulation was also observed with poly[d(A-T)], primed M13 DNA, and heat-denatured DNA.

Animals↗
PubMed1989

Existence of Mg2+-dependent, neutral sphingomyelinase in nuclei of rat ascites hepatoma cells.

A sphingomyelinase, which specifically hydrolyzes sphingomyelin into ceramide and phosphocholine, was solubilized from nuclear matrix fraction of rat ascites hepatoma, AH7974 cells. The solubilized enzyme was subjected to Mono Q column chromatography in an FPLC system. The sphingomyelinase which was adsorbed on the column and eluted at 0.25-0.5 M NaCl was characterized. The enzyme required 10 mM MgCl2, 0.01% Triton X-100, 1 mM dithiothreitol, and a higher concentration of buffer than 1 M for its maximal activity, and the optimal pH was 6.7-7.2 in 2 M Tris/acetic acid or 7.5 in 2 M potassium acetate/acetic acid. N-Ethylmaleimide completely inhibited the enzyme activity at 0.2 mM. Therefore, this enzyme is classified as a Mg2+-dependent, neutral sphingomyelinase. The sphingomyelinase sedimented at 4.3S through a 10-30% glycerol gradient containing 2 M potassium acetate. This enzyme was highly specific to sphingomyelin and did not hydrolyze phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and phosphatidylinositol. Various characteristics of the nuclear sphingomyelinase were similar to those of the plasma membrane enzyme except its requirement for a high concentration of buffer and SH-reagent.

Animals↗
PubMed1989

Rapid purification and structural study of DNA topoisomerase I from human Burkitt lymphoma Raji cells.

We have developed a rapid purification method for DNA topoisomerase I from Raji cells, a human Burkitt lymphoma cell line, using ammonium sulfate fractionation followed by chromatography on a Mono S column (FPLC, Pharmacia). By this method, the enzyme could be purified to near homogeneity within one day. Electrophoresis on sodium dodecyl sulfate polyacrylamide gel revealed that the final preparation is mainly composed of a 100-kDa protein. The major enzyme activity sedimented through a glycerol density gradient at 5.7S, accompanied with a minor peak at 8.7S. The former may correspond to the monomer of the 100-kDa polypeptide, and the latter, to its dimeric form. The gel filtration study of the crude extract revealed an active molecular species of 200 kDa, in addition to 100 kDa, and lower molecular weight forms. These results suggest that DNA topoisomerase I is largely in monomeric form, but also has a minor population of the dimeric form.

Burkitt Lymphoma↗