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Biomedical subjects

N Kojima

Publications and source records attributed to N Kojima.

At least 163 records · Page 9Linked to original sources
PubMed1991

Delayed onset of intraventricular hemorrhage following removal of acute subdural hematoma--case report.

A 68-year-old male presented with neurological deterioration after a lucid interval following head trauma. Computed tomographic (CT) scans on admission demonstrated a subdural hematoma in the right frontotemporal region accompanied by subarachnoid hemorrhage in the right Sylvian and interhemispheric fissures. The subdural hematoma was removed via a right frontotemporoparietal craniectomy. However, immediate postoperative CT scans revealed hemorrhage in the third and both lateral ventricles, apparently separate from the primary hemorrhages. Decompressive rupture of damaged subependymal veins is suggested as the cause of the delayed traumatic intraventricular hemorrhage.

Acute Disease↗
PubMed1991

Influence of growth rate and exposure to bulls on age at puberty in beef heifers.

Two experiments were conducted to test the following hypotheses: 1) exposure of beef heifers to sterile bulls increases the proportion of heifers attaining puberty by 14 mo of age and 2) rate of growth interacts with bull exposure to influence age at puberty in beef heifers. In Exp. I, heifers were assigned to one of two treatments: 1) heifers were exposed to bulls (BE; approximately 70-d period of exposure) or 2) heifers were isolated from bulls (NE) and served as controls. In Exp. II, heifers were assigned to either BE or NE treatments (175-d period of exposure to bulls) and were fed to gain at a moderate (MG; .6 kg/d) or high (HG; .8 kg/d) growth rate. Blood samples were collected twice weekly to determine concentrations of progesterone indicative of onset of corpus luteum function and puberty. In Exp. I a greater (P less than .05) proportion of heifers receiving the BE treatment than of heifers receiving the NE treatment initiated corpus luteum function by 14 mo of age. In Exp. II, there was a bull exposure x growth rate interaction (P less than .05). The effect of bull exposure was greater within the HG groups than within the MG groups. However, heifers fed to attain a moderate or high growth rate and exposed to bulls attained puberty at younger ages than heifers not exposed to bulls and fed to attain a moderate or high growth rate. Mean ages at puberty were 375, 422, 428, and 449 (pooled SEM = 8.6) d for heifers in the BE-HG, BE-MG, NE-HG, and NE-MG groups, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

[Continuous infusion chemotherapy using an infusional port in colorectal cancer with liver metastases].

Chemotherapy for colorectal cancer with liver metastases following surgical operation for primary tumor should be selected following surgical intervention. Continuous infusion chemotherapy using an infusional port was selected for unresectable metastasis due to colorectal cancer in our department. The catheter was placed in the hepatic artery through a gastroduodenal by operative procedure. 5-fluorouracil (5-FU) and mitomycin C (MMC) were used as chemotherapeutic agents. After MMC was given at 10 mg/body by bolus, administration of 5-FU was continuously infused at 250 mg/day for 2 weeks, followed by a 2-week interval. Drug administration was done by implanted pump hepatic arterial infusion. Seventeen of the patients with liver metastasis underwent this chemotherapy from 1986 through 1990. Results of the infusion chemotherapy were as follows. Value of serum CEA decreased until two courses were given in all cases. In 11 cases, the tumor size on CT was remarkably smaller. In these patients, however, there were many complications due to the catheter used for catheter replacement, drug leakage, drug extravasation and so on. We concluded that although this chemotherapy was very effective, the method should be improved in terms of the material, the location of catheter tip and the like.

Administration, Oral↗
PubMed1991

Lipoxygenases from soybeans and rabbit reticulocytes: inactivation and iron release.

Various inactivation methods were applied to lipoxygenases from soybean (isoenzyme 1) and rabbit reticulocytes to compare the inactivation behaviour of both enzymes and to elucidate the state of the iron which is known to be involved in the catalytic reaction of lipoxygenases: 1. Titration of the enzyme with mercury compounds shows that there are one or two SH groups responsible for the loss of activity in the presence of mercury. The SH groups seem not to be involved in the tight iron binding. 2. Inactivation by chelating agents such as o-phenanthroline or batho-phenanthroline sulfonic acid occurs only in the presence of reducing agents (mercaptoethanol and ascorbic acid). Our data support a co-oxidation mechanism. The complexation of iron by chelators is not the rate-limiting step. Both lipoxygenases show a very similar behaviour in this respect despite the fact that the reticulocyte enzyme requires the addition of trace amounts of copper ions for efficient inactivation. 3. Release of iron from the enzyme is also achieved by denaturation with guanidinium hydrochloride (Gu-HCl). In all cases, inactivation and release of iron were irreversible processes. 4. A sequence comparison for both animal and plant lipoxygenases shows strongly conserved amino acids, especially histidines and hydrophobic residues, which possibly may be involved in iron complexation and substrate binding.

Amino Acid Sequence↗
PubMed1990

Expression of three drebrin isoforms in the developing nervous system.

Drebrins are developmentally regulated brain proteins which were first isolated from brains of 10-day chick embryos. They are classified into three forms, drebrins E1, E2 and A. Cloning of drebrin cDNAs revealed that each drebrin isoform is encoded in an independent mRNA. Genomic Southern blot analysis and cloning of a drebrin gene revealed that the mRNAs of three drebrin isoforms are generated by alternative RNA splicing from a single gene. Immunohistochemistry and in situ hybridization analysis of the embryonic cerebellum indicated that drebrin mRNA is first transcribed in postmitotic neurons and that there seem relations between cell migration and expression of drebrin E1.

Animals↗
PubMed1990

[Long-term results of hydrocephalus with myelomeningocele].

This paper reviews long-term follow-up studies of 78 hydrocephalic patients with myelomeningocele. Seventy-eight (95%) out of 82 patients with myelomeningocele had hydrocephalus. CT, MRI, CT cisternography, and monitoring of intracranial pressure (ICP) with infusion methods were performed to evaluate the indication of shunt insertion or shunt independency. These hydrocephalic patients consisted of the following two groups: (1) Early treated group. Sixty-four cases received initial cerebrospinal fluid (CSF) diversion operation within 2 years of life. Sixty-three patients had a ventriculoperitoneal (VP) or a ventriculoatrial (VA) shunt. All the patients of this group showed progressive signs and symptoms of increased ICP due to hydrocephalus. The mean age at the initial shunt placement was 10 weeks. The mean value of Evans' index before shunting was 47%, which corresponded to moderate ventriculomegaly. 48% of this group showed slit-like ventricles on postoperative CT scans, where 52% had normal or only mildly dilated ventricles subsequent to shunting. There were two instances (3%) of the so-called "slit ventricle syndrome" and one instance of "isolated fourth ventricle", who had undergone multiple shunt revisions. Shunt revisions were performed on fifty-two occasions in this group. The mean number of shunt revisions per child was 2.8. Sixty among 64 patients of this group were suitable for evaluating shunt dependency with long-term follow-up period. Forty-two out of 60 patients were considered to be shunt dependent, who underwent multiple shunt revisions after 6 months of age. These patients had signs and symptoms of increased ICP, neurological deterioration, and enlarged ventricles when their shunts were blocked. There were four cases of slowly progressive (shunt dependent) hydrocephalus, who did not show clinical signs and symptoms of shunts malfunction in spite of progressive ventriculomegaly and abnormal findings of CT cisternography and ICP monitoring. Only two patients (3%) proved to be shunt independent. Consistently their ventricles were mildly dilated. These results suggest a very low incidence of true arrest of hydrocephalus after shunt operation. (2) Late treated group. Fourteen cases were diagnosed or treated for hydrocephalus after 7 years of age. Six out of fourteen patients had remarkable hydrocephalus whose Evans' index exceeded 51%. The mean value of Evans' index was 48% in this group. Six patients had progressive signs and symptoms of hydrocephalus and were shunted. ICP monitoring and studies of CSF dynamics revealed abnormal findings in ten out of 14 cases in spite of preservation of good intelligence.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1989

Specific interaction between gangliotriaosylceramide (Gg3) and sialosyllactosylceramide (GM3) as a basis for specific cellular recognition between lymphoma and melanoma cells.

In view of the possible role of glycosphingolipids in defining the specificity of cell-cell interactions, the key molecules for recognition of cell surface glycosphingolipids have been studied. In addition to previously suggested recognition mechanisms involving endogenous lectins and glycosyltransferases, an alternative possibility, based on carbohydrate-carbohydrate (Lex-Lex) interaction, has been raised (Eggens, I., Fenderson, B., Toyokuni, T., Dean, B., Stroud, M., and Hakomori, S. (1989) J. Biol. Chem. 264, 9476-9484). We now report a highly specific interaction between gangliotriaosylceramide (Gg3, GalNAc beta 1----4Gal beta 1----4Glc beta 1----Cer) and sialosyllactosylceramide (GM3, NeuAc alpha 2----3Gal beta 1----4Glc beta 1----Cer). The interaction requires a bivalent cation (Ca2+ or Mg2+) and can be inhibited by sialosyl 2----3 lactose, anti-GM3 antibody (DH2), anti-Gg3 antibody (2D4), or EDTA. The strength of interaction between GM3 liposome and the Gg3-coated plastic surface was highly density-dependent. The mouse lymphoma L5178 AA12 cell line (high expressor of Gg3) interacted specifically with the mouse B16 melanoma cell line (high expressor of GM3). The interaction was inhibited by 5 mM sialosyllactose, anti-GM3 antibody, anti-Gg3 antibody, and EDTA in analogy to GM3-Gg3 interaction. L5178 AV27, a genetically related variant clone which does not express Gg3, showed no interaction with B16 cells. Untreated AA12 cells, but not 2D4-treated AA12 cells or AV27 cells, interacted with GM3 coated on the plastic surface. These findings suggest a specific interaction between AA12 cells and B16 cells based on Gg3-GM3 interaction.

Animals↗
PubMed1989

[Two cases of Graves' disease with anti-thyroid hormone autoantibodies: the effect of subtotal thyroidectomy on the titers of anti-thyroid hormone autoantibodies and anti-Tg antibodies].

We experienced two cases of Graves' disease associated with anti-thyroid hormone autoantibodies (Case 1: anti-T4, Case 2: anti-T3). Both cases underwent subtotal thyroidectomy, and titers of anti-thyroid hormone antibodies and anti-Tg antibodies were compared before and after operation. In case 1, titers of both anti-T4 and anti-Tg antibodies decreased after operation, whereas in Case 2, titers of both anti-T3 and anti-Tg were unchanged before and after operation. There was a significant positive correlation between titers of anti-T4 and anti-Tg antibodies in Case 1 (r = 0.90, P less than 0.01), and anti-T3 and anti-Tg antibodies in Case 2 (r = 0.64, P less than 0.01). These results strengthen the possibility that the antigen of anti-thyroid hormone autoantibodies in both cases is the Tg molecule.

Autoantibodies↗
PubMed1989

Determination of bromperidol in serum by automated column-switching high-performance liquid chromatography.

A column-switching high-performance liquid chromatographic method with ultraviolet detection is described for the simple and rapid determination of bromperidol, a neuroleptic drug, in dog and human sera. The drug in serum and trifluperidol added to the serum as an internal standard were extracted with hexane-chloroform, and the extract was subjected to automated column-switching high-performance liquid chromatography using a hydrophilic metaacrylate polymer column (TSK gel PW precolumn) for sample clean-up and a reversed-phase column (TSK gel ODS-80TM) for separation. The detection limit of bromperidol is 0.3 ng/ml serum and the recovery of bromperidol added to serum (2.7-16.0 ng/ml) was satisfactory with a standard deviation of 3% or less.

Adult↗
PubMed1989

[Changes in anti-thyroid hormone and anti-thyroglobulin antibodies during thyroid hormone(s) or prednisolone treatments in 3 cases of Hashimoto's thyroiditis].

We have experienced 3 cases of Hashimoto's thyroiditis with anti-thyroid hormone antibodies. Changes in titers of anti-thyroglobulin(Tg) and anti-thyroid hormone antibodies during 6 year (Cases 1 and 2) and 7 year (Case 3) observation periods were examined in each case. Cases 1 (13-year-old) and 2 (10-year-old) are sisters with hypothyroidism whose chief complaint was short stature. They were diagnosed as having Hashimoto's thyroiditis by needle biopsy of the thyroid gland. Presence of anti-thyroid hormone antibodies were found in the sera of both cases (Case 1: anti-thyroxine(T4) antibodies, Case 2: anti-triiodothyronine(T3) antibodies). They were treated with synthetic T4 or combined therapy of T3 and T4, and serial sera obtained during the 6 year treatment period were tested for the titers of anti-Tg and anti-thyroid hormone antibodies. Case 3 (23-year-old female), who was diagnosed as having Hashimoto's thyroiditis associated with systemic lupus erythematosus (SLE) and Sjögren's syndrome had been treated with prednisolone(PSL) for 8 years. After one year of strating the treatment, she was found to have unusually low serum T3 measured by radioimmunoassay. Further examination revealed the presence of anti-T3 antibodies in her serum. Serial sera obtained during the 7 year observation period were tested for the titers of anti-Tg and anti-T3 antibodies. In cases 1 and 2, replacement therapy with thyroid hormone resulted in the decrease of titers of anti-thyroid hormone antibodies. In addition, increase in serum TSH concentrations was accompanied with increased titers of anti-Tg and anti-thyroid hormone antibodies in all 3 cases. The exact mechanism for it is not clear.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

[Fluctuations in the titers of anti-thyroid hormone and anti-thyroglobulin antibodies in 4 cases of Graves' disease during long-term treatment period].

We studied 4 cases of Graves' disease with anti-thyroid hormone antibodies. Changes in the serum levels of triiodothyronine(T3), thyroxine(T4), free T4, thyrotropin(TSH), and thyroglobulin(Tg), as well as titers of anti-Tg antibodies, anti-thyroid hormone antibodies, anti-TSH receptor antibodies(TRAb) and anti-microsomal antibodies(MCHA) during 2 10 years' treatment periods were examined in each case. Case 1; A woman, who was diagnosed as having Graves' disease when she was 10 years old, had been treated with methimazole(MMI) or propylthiouracil(PTU). Treatment with the antithyroid drug had been discontinued by herself when she was 19 years old until she was 24 years old, when she was pregnant and consulted our hospital. Since her serum levels of T3 were unusually high, examination of her serum for the presence of anti-T3 antibodies was done. The presence of anti-T3 antibodies in her serum was confirmed. Case 2; A woman, who was diagnosed as having Graves' disease at the age of 41, had been treated with MMI or PTU. Presence of serum anti-T3 antibodies was found in a screening test for the antibodies. Serial sera were obtained during the 5 year observation period when she was treated with MMI, PTU, and subtotal thyroidectomy. Titers of anti-Tg antibodies in her sera were in the normal range. Case 3; A woman, who was diagnosed as having Graves' disease at the age of 11, had been treated with MMI or PTU. Presence of anti-T3 and anti-T4 antibodies were found in her sera in a screening test. Serial sera obtained during the 4 year treatment period were tested. Case 4; A woman, who was diagnosed as having Graves' disease at the age of 14, had been treated with MMI. Presence of anti-T3 and anti-T4 antibodies was found in her sera in a screening test. Serial sera obtained during the 2 year treatment period were tested. Titers of anti-Tg were increased when the levels of TSH or titers of TRAb were increased. The results suggested that TSH and TRAb, which are thyroid stimulating substances, increased serum levels of Tg, which resulted in the increase of titers of anti-Tg. Because of the possibility that administration of PSL could modify B lymphocyte functions, periods during which PSL was administered were excluded from the examination of the correlation between Tg concentrations or titers of anti-Tg and titers of anti-thyroid hormone antibodies, as in Cases 2 and 4, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1989

Effect of 8-anilino-1-naphthalene sulfonic acid (ANS) on the interaction between thyroid hormone and anti-thyroid hormone antibodies.

Effect of 8-anilino-1-naphthalene sulfonic acid (ANS) on the interaction between thyroid hormone and anti-thyroid hormone antibodies was examined. Addition of 5.1 x 10(6) or 6.3 x 10(6) molar excess of ANS, respectively, enhanced the binding of 125I-T3 or 125I-T4 to their respective autoantibodies. However, further increase in ANS concentration resulted in a decrease in binding. These results suggest that the optimum concentration of ANS for the detection of anti-thyroid hormone antibodies is 5 approximately 6 x 10(6) molar excess of ANS to 125I-T3 or 125I-T4. On the other hand, addition of 10(4) molar excess of ANS concentration decreased the binding of 125I-insulin to anti-insulin antibodies. It was therefore suggested that the effect of ANS could be a nonspecific one and likely due to its negative charge.

Anilino Naphthalenesulfonates↗
PubMed1989

Effect of dietary alpha-linolenate/linoleate balance on collagen-induced platelet aggregation and serotonin release in rats.

Male Sprague-Dawley rats at 3 weeks of age were weaned to a diet supplemented either with perilla seed oil [alpha-linolenic acid (alpha-LnA)/linoleic acid (LA) = 3.66] or with safflower seed oil (alpha-LnA/LA less than 0.01) for 5-6 weeks. The eicosapentaenoic acid (EPA)/arachidonic acid (AA) ratio in platelet phospholipids was much higher in the perilla oil group than in the safflower oil group. Platelet aggregability determined turbidometrically varied greatly among individual animals, and the difference in platelet aggregability between the two dietary groups was relatively small when higher concentrations (15 and 20 micrograms/ml) of collagen were used. However, when platelet aggregability was determined as an all-or-none phenomenon at lower concentrations (7.5 and 10 micrograms/ml) of collagen, a very distinct difference was observed between the two dietary groups; aggregability was much lower in the perilla oil group than in the safflower oil group. Collagen-induced serotonin release from platelets was significantly reduced in the perilla oil group as compared with the safflower oil group. These results emphasize the importance of estimating aggregability at threshold concentrations of collagen and confirm that dietary manipulation of the essential fatty acid balance could be useful in reducing the thrombotic tendency.

Animals↗
PubMed1989

Experimental induction of splayleg in piglets by pyrimethamine.

Dietary administration of 3.6 mg/kg (BW)/day of pyrimethamine (PYR) to the 10 pregnant Goettingen minipigs for the 1st quarter (during days 11 to 16) or the 2nd quarter (during days 17 to 22) of the organogenetic period elicited the congenital splayleg (CSL) in 20 out of 27 live newborns. Only a splayleg piglet out of 18 was found in the control group. The incidence of stillbirth was higher in the PYR groups than the control group, but no major external malformation was observed in the piglets of the PYR groups. Histological and biochemical examinations of the muscles from the hindleg, foreleg and truncus were carried out. The severity of myofibrillar hypoplasia depended on neither CSL symptoms nor PYR administration. Although a significant decrease of protein content of the muscles was observed in the piglets of the PYR groups, the mechanism underlying the pathogenesis of induced splayleg was obscure.

Animals↗
PubMed1989

Liposomes coupled with monoclonal antibodies against glioma-associated antigen for targeting chemotherapy of glioma.

Liposomes have a variety of attributes as a drug delivery system. Targeting of liposomes to specific cells has been investigated by using appropriate cytophilic ligands such as monoclonal antibodies (MAb's). In the present study, liposomes with selective cytotoxicity toward glioma cells were obtained. An MAb which reacts with a glioma-associated antigen, G-22-MAb, was coupled with liposomes by the cross-linking reagent dipalmitoyl L-alpha-phosphatidylethanolamine 3-(2-pyridyldithio)propionate. Interaction of the liposomes with glioma cells was morphologically observed by fluorescence microscopy, and uptake of liposomal contents into glioma cells was analyzed by flow cytometry using carboxyfluorescein as a marker. It was demonstrated that G-22-MAb could be coupled with liposomes without altering its specificity toward glioma cells and that coupling with the MAb led to a significant increase in the uptake of liposomal contents into glioma cells. Liposomes containing an antitumor drug, methotrexate (MTX), were prepared and their cytotoxicity was examined by a colorimetric growth assay. Upon incorporation of MTX into the MAb-coupled liposomes, the cytotoxicity toward glioma cells was increased 100-fold as compared with free MTX. These results indicate that G-22-MAb-coupled liposomes containing MTX have selective cytotoxicity toward glioma cells and could be utilized for targeting the chemotherapy of gliomas.

Antibodies, Monoclonal↗
PubMed1989

Structural elucidation of aculeximycin. I. Further purification and glycosidic bond cleavage of aculeximycin.

A new insecticidal antibiotic, aculeximycin (ACM), was produced by an actinomycete identified as Streptosporangium albidum. ACM has been successfully isolated from culture filtrate by a combination of Diaion HP-20, Amberlite CG-50, reversed phase silica gel and Sephadex LH-20 chromatographies. It was found that ACM is a basic glycosidic antibiotic with a molecular weight of 1,672 including five monosaccharide units, three double bonds and a hemiketal ring by preliminary spectral analyses. Treatment of ACM with 1,8-diazabicyclo[5,4,0]undecene-7 caused a glycosidic bond cleavage to give aculexitriose, pseudoaglycones I and II.

Actinomycetales↗