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Biomedical subjects

K Toda

Publications and source records attributed to K Toda.

At least 145 records · Page 8Linked to original sources
PubMed1994

Enzyme linked immunosorbent assay (ELISA) and immunoprecipitation studies on anti-goblet cell antibody using a mucin producing cell line in patients with inflammatory bowel disease.

Circulating anti-goblet cell antibody and its corresponding antigen in patients with inflammatory bowel disease were investigated. Anti-goblet cell antibody in the serum was examined by immunocytochemistry and enzyme linked immunosorbent assay (ELISA), using a colonic cancer cell line, HT29-18-N2, which differentiates into intestinal goblet cells. The frequencies of anti-goblet cell antibody detected by immunocytochemistry were 14 in 48 patients with ulcerative colitis (29%) and five in 15 patients with Crohn's disease (33%). By ELISA, the frequencies of anti-goblet cell antibody were 38% in ulcerative colitis and 33% in Crohn's disease. This antibody did not relate directly to anti-neutrophil cytoplasmic antibodies (ANCA), although the serum samples positive for anti-goblet cell antibody were commonly positive for ANCA in ulcerative colitis. Immunoprecipitation and SDS polyacrylamide gel electrophoresis (PAGE) study showed that the antibody in the ELISA positive serum samples recognised a > 200 kD goblet cell antigen, which remained unchanged after reduction, indicating that it consists of single chain polypeptides. These results suggest that there is a subgroup of inflammatory bowel disease that has circulating anti-goblet cell antibody reactive with a > 200 kD antigen. The antibody detected by newly established ELISA will be a disease marker for this group and the identification of the corresponding antigens may be important for the understanding of the underlying immune abnormalities.

Adolescent↗
PubMed1994

Expression of the gene encoding aromatase cytochrome P450 (CYP19) in fetal tissues.

The formation of estrogens from C19 steroids is catalyzed by a specific form of cytochrome P450, aromatase cytochrome P450 (P450arom; the product of the CYP19 gene). In previous studies we have demonstrated that in adult human tissues and placenta, expression of the CYP19 gene is regulated in part by means of tissue-specific promoters through the use of alternative splicing mechanisms. In addition to placenta, a number of fetal tissues express aromatase, including liver, intestine, skin, and brain. To characterize the CYP19 transcripts present in these and other fetal tissues, we have used reverse transcription and polymerase chain reaction to amplify sequences corresponding to the various untranslated exons from RNA extracted from these tissues. In addition, we have prepared cDNA libraries using RNA from these tissues by the method of rapid amplification of cDNA ends. Sequencing of clones derived from these libraries has been employed to confirm the presence of sequence corresponding to untranslated exons at the 5'-ends of P450arom transcripts. Based on these findings, we conclude that in fetal tissues other than placenta, transcripts containing sequence found in the exon we have previously named I.4 appear to be the most common. Such sequences have been found in cells in which P450arom expression is stimulated by glucocorticoids. Thus, the presence of such transcripts in fetal liver RNA is consistent with our previous observations that aromatase activity in fetal hepatocytes is stimulated by glucocorticoids. Secondly, transcripts are present in the fetal adrenal, although no aromatase activity has ever been detected in this tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Aromatase↗
PubMed1994

A new skin equivalent: keratinocytes proliferated and differentiated on collagen sponge containing fibroblasts.

Three types of artificial skin containing keratinocytic components were prepared and tested for comparison. Keratinocytes were cultured on the artificial skin dermis (collagen sponge) by the air-liquid interface culture method. In order to create continuous keratinocytic layers on the artificial skin dermis, pores of its uppermost layer were filled beforehand with type I collagen gel, Matrigel, or fibroblasts. A band of keratinocytes consisting of two to six cell layers was formed on collagen gel-coated artificial skin dermis. On Matrigel-coated artificial skin dermis, keratinocytes were piled up into about 20 cell layers, but cell differentiation was incomplete; cornified material was not fully developed, and the proportion of cuboidal cells was very high compared with normal epidermis. Keratinocytes formed continuous layers on the fibroblasts-artificial skin dermis complex without gel coating. Keratinocytes proliferated well and differentiated properly on this matrix, and their histologic appearance was similar to that of normal epidermis. Thus keratinocytes cultured on the fibroblast-artificial skin dermis complex seem to be a good skin equivalent.

Adult↗
PubMed1994

Enhanced therapeutic effect on murine melanoma and angiosarcoma cells by boron neutron capture therapy using a boronated metalloporphyrin.

We have already achieved successful treatment of several human patients with malignant melanoma by boron neutron capture therapy (BNCT) using 10B1-paraboronophenylalanine (10B1-BPA). In this communication we used a new compound, a manganese boronated protoporphyrin (Mn-10BOPP), and compared it to 10B1-BPA.HCl with respect to uptake in murine melanoma and angiosarcoma cells as well as to their respective cell killing effects using BNCT. Mn-10BOPP was found to be 3 to 10 times more effectively taken up by melanoma cells and angiosarcoma cells than 10B1-BPA.HCl when the content of 10B was measured by the new method, inductively coupled plasma-mass spectrometry (ICP-MS). In addition, melanoma cells and angiosarcoma cells preincubated with Mn-10BOPP were 15 to 20 times more efficiently killed by BNCT than cells preincubated with 10B1-BPA.HCl. These results suggest that Mn-10BOPP is a suitable compound for BNCT of not only malignant melanoma but also angiosarcoma.

Animals↗
PubMed1994

[The significance of intra-arterial infusion therapy for neoadjuvant chemotherapy].

Arterial infusion therapy with anticancer drugs is now attracting attention as a valuable modality for locally advanced breast cancer. Since 1977, we have used this therapy in 122 patients with primary breast cancer. The present report mainly discusses the clinical and histological response as well as the prognosis. The anticancer drugs were mainly given by two routes, infusion into the internal mammary artery and the subclavian artery. Continuous infusion of 5-FU and intermittent injections of MMC, ADR, 4'-epi-ADR and THP-ADR were jointly or individually made in each artery. Clinical response, defined as CR + PR, was noted in 48.4% of 5-FU group and 72.7% of ADR-MMC group. Histological response according to Shimosato Criteria, defined as grade IIb or better, appeared in 45.2% of main tumors and 25.4% of metastatic lymph nodes in the 5-FU group, and 70.9% main tumors and 46.3% of metastatic lymph nodes in the ADR-MMC group. The non-infusion group contained 27.7% of stage IIIb, against 72.2% in the infusion group. The 5-year overall survival rates were non-infusion group 62%, 5-FU group 34.1% and ADR-MMC group 66.2%. A significant difference was seen between the 5-FU infusion group and the ADR-MMC group (p = 0.03). Administration of high dose medroxy progesterone acetate for two weeks and 4'-epi-ADR infusion chemotherapy resulted in an excellent histological response. This combination therapy is a promising neoadjuvant chemo-endocrine therapy for advanced breast cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Carcinoembryonic antigen mediates in vitro cell aggregation induced by interferon-gamma in a human colon cancer cell line: requirement for active metabolism and intact cytoskeleton.

The homotypic cell aggregation of a carcinoembryonic antigen (CEA) positive colon cancer cell line (Colo 205) was induced in vitro by interferon-gamma (IFN-gamma) treatment. Divalent cations were required for this aggregation, as it was inhibited by EDTA. The partial inhibition by cytochalasin B and the complete inhibition by a mixture of sodium azide and 2-deoxyglucose suggests that the aggregation requires the integrity of cytoskeleton and active metabolism. The expression of CEA was increased in the cytoplasm and on the membrane of Colo 205 by IFN-gamma treatment. Furthermore, this aggregation was inhibited completely by anti-CEA monoclonal antibody (mAb) and partially by mAb against intercellular adhesion molecule-1. This in vitro study suggests that CEA molecule participates in the IFN-gamma induced homotypic adhesion of some CEA positive cancer cells and that IFN-gamma has an important role in the regulation of cell-cell interaction mediated by CEA molecule.

Antibodies, Monoclonal↗
PubMed1993

Molecular cloning of a cDNA showing alternative splicing of the 5'-untranslated sequence of mRNA for human aromatase P-450.

A new type of full-length cDNA clone encoding human aromatase P-450 was isolated from a human placental cDNA library. The clone, designated as pES-4, has a 3130-bp insert. The nucleotide sequences of the translated region and the 3'-untranslated region of the insert of pES-4 are exactly identical with those of the cDNA clone characterized previously. However, the sequence of the 5'-untranslated region of the insert has characteristic feature, i.e. an extra sequence of 109 bp is present at a junction between exon 1 and exon 2 on the processed human aromatase mRNA. Analysis of the genomic clones containing the region between exon 1 and exon 2 of the human aromatase P-450 gene reveals that the 109-bp genomic segment, encoding the same sequence as the extra sequence observed in pES-4, is located approximately 10-kbp downstream of exon 1 and that the nucleotide sequences of the 5'-flanking and the 3'-flanking regions of the segment conform to the GT-AG rule for RNA splicing. By means of reverse transcription and polymerase chain reaction, relative amounts of the pES-4-type mRNA are estimated to be approximately 4.8% and 2.3% of the processed aromatase P-450 mRNA in human placenta and human BeWo choriocarcinoma cells, respectively. These results indicate that the segment of 109 bp between exon 1 and exon 2 is a new exon hitherto unidentified and that heterogeneity observed in the 5'-untranslated sequence of human aromatase P-450 mRNA is, at least in part, caused by alternative splicing of this new exon.

Alternative Splicing↗
PubMed1993

Congenitally defective aldosterone biosynthesis in humans: inactivation of the P-450C18 gene (CYP11B2) due to nucleotide deletion in CMO I deficient patients.

CYP11B2, the gene coding for steroid 18-hydroxylase (P-450C18), has been recently shown to be the same gene as that for corticosterone methyl oxidase type I and type II (CMO I & II) which were previously postulated to catalyze the final two steps in the biosynthesis of aldosterone in humans. Molecular genetic analysis of CYP11B2 of three patients affected with CMO I deficiency has revealed that deletion of 5 nucleotides occurs exclusively in exon 1, resulting in a frameshift to form a stop codon in the same exon. Thus, P-450C18 is not produced at all due to the mutation, causing a complete lack of aldosterone biosynthesis in the patients. Restriction fragment length polymorphism analysis has demonstrated that the patients are homozygous and the unaffected parent is heterozygous as for the mutation, indicating that CMO I deficiency is inherited in an autosomal recessive manner. These results provide the molecular genetic basis for the characteristic biochemical phenotype of CMO I deficient patients.

Aldosterone↗
PubMed1993

Influence of fatty acid absorption on bidirectional release of immunoglobulin A into intestinal lumen and intestinal lymph in rats.

Effects of absorption of long and middle chain fatty acids on IgA secretion into the intestinal lumen and intestinal lymph and the factors which evoke changes in IgA secretion during the absorptive process were examined in rat small intestine. Bidirectional secretion of IgA from the intestinal mucosa into the intestinal lumen and intestinal lymph was continuously observed in the control condition. Perfusion of oleic acid (a long-chain fatty acid) micelle into the jejunal loop induced a significant increase in IgA output into the intestinal lymph. In contrast, lymphatic output of IgA was significantly decreased when oleic acid micelle was administered intraduodenally. Absorption of octanoic acid, a middle-chain fatty acid, did not produce any significant changes in IgA output into either direction. CR1505, a CCK-receptor antagonist, significantly attenuated the oleic acid-induced increase in IgA secretion into the intestinal lumen, but did not affect the oleic acid-induced decrease in lymphatic IgA secretion. Pluronic L-81, an inhibitor of chylomicron formation and secretion, significantly attenuated the decrease in IgA output into the intestinal lymph during oleic acid absorption without affecting the luminal IgA output. The rate of release of IgA into the intestinal lumen is stimulated by absorption of long-chain fatty acids possibly through the influence of locally released CCK, while the transport process of IgA into lymphatics is controlled by a different mechanism which is closely correlated with the intracellular formation and secretion of chylomicron.

Animals↗
PubMed1993

Chronometrical analysis of event-related potentials and reaction time in patients with multiple lacunar infarcts.

We measured the visual event-related potentials (ERPs) and reaction time (RT) in 31 patients with multiple lacunar infarcts and 18 age-equivalent normal subjects. The N2 and RT latencies of the patients were significantly longer than those of normal subjects, although P2 and P3 latencies did not differ between the two groups. However, the time from N2 to RT did not differ between the two groups. These observations suggest that the impairment of cognitive information processing in these patients arises from an uncertainty in classifying the perceived event, while motor organization time is relatively well preserved. In addition, the N2 latency may be more sensitive in detecting cognitive impairment in such patients.

Aged↗
PubMed1993

Murine endothelial cell line cells, F-2: interaction with leukocytes and cytokines production.

Flowcytometry demonstrated that murine endothelial cell line F-2 expresses MHC class I antigen, FcR II, Mac-1 and vascular cell adhesion molecule-1 (VCAM-1), but not intercellular adhesion molecule-1 (ICAM-1) and class II antigen. However, co-culturing with TNF-alpha for 24 hr resulted in the increased expression of ICAM-1, and the decreased expression of VCAM-1. IL-1 alpha and IFN-gamma exerted this regulatory effect on VCAM-1 but not on ICAM-1. T (Con A blast) and B (LPS blast) cells adhered to F-2 cells at almost equal levels, and the adhesion was enhanced 20 to 50% when the cells were precultured with TNF-alpha for 24 hr. The inhibition assay using either (anti-ICAM-1 + anti-LFA-1, lymphocyte function-associated antigen-1) or (anti-VCAM-1 + anti-VLA-4, very late antigen-4) mAbs demonstrated that the ICAM-1 system was utilized more preferentially by T than B blasts when F-2 cells were stimulated with TNF-alpha, and the VCAM-1 system was vice versa under the unstimulated and stimulated conditions. Granulocytes also adhered to F-2 cells, but no mAbs could inhibit the adhesion. Although F-2 cells produced a considerable amount of IL-6, GM-CSF and neutrophil chemotactic activity, a 24 hr incubation with TNF-alpha resulted in an increase of 12 fold in IL-6 and 3 fold in neutrophil chemotactic activity production.

Animals↗
PubMed1993

Changes of proliferative activity and phenotypes in spontaneous differentiation of a colon cancer cell line.

We examined the alterations of proliferative activity and c-myc expression of a colon cancer cell line (Caco-2) during its spontaneous differentiation. Caco-2 cells were cultured in various types of media and the degree of differentiation was monitored in terms of dome formation in cell monolayers and expression of alkaline phosphatase (ALP) activity. In Caco-2 cells cultured with Eagle's minimum essential medium (EMEM) containing 10% fetal calf serum (FCS), dome formation was demonstrated and ALP activity was markedly increased after the cells reached confluence. Five-fold reduction of c-myc mRNA and a marked decrease in S-phase cells were observed in the differentiated cells. These changes were not induced in FCS-free EMEM. The addition of insulin and transferrin to FCS-free EMEM did not induce cell differentiation or reduction of c-myc mRNA expression. When Caco-2 cells were cultured with three different serum-free media, the induction of dome formation and the increase of ALP activity were observed to varying degrees. Expression of c-myc mRNA in the cells cultured with one serum-free medium decreased to a level similar to that in fully differentiated cells cultured with EMEM containing 10% FCS. These results suggest that a spontaneous switch from a proliferative state with high c-myc expression to differentiated phenotype occurs after cells reach confluence and depends on the culture conditions.

Cell Differentiation↗
PubMed1993

Germ cells of the mouse testis express P450 aromatase.

Estrogen production within the testis has been a subject of considerable controversy for many years. Several studies have shown that both Sertoli and Leydig cells produce estrogen during different stages of development. Therefore, we have conducted experiments to localize aromatase, a cytochrome P450 enzyme that converts androgen to estrogen, within the testis. First, P450 aromatase (P450arom) was localized in germ cells of the adult mouse testis by immunocytochemistry, using an antiserum generated against purified human placental cytochrome P450arom. In the germinal epithelium, P450arom was located primarily in the Golgi region of round spermatids, throughout the cytoplasm of elongating spermatids, and along the flagella of late spermatids. Second, localization of P450arom within the germinal epithelium was supported by Western blot analysis of isolated germ cells. Third, Northern blot analysis using a mouse P450arom cDNA probe indicated that the mRNA for the mouse P450arom was present in testicular germ cells. Fourth, P450arom activity was measured in germ cells by the 3H2O water assay. Based upon these observations, we conclude that germ cells are a site of estrogen synthesis in the adult mouse testis.

Animals↗
PubMed1993

A nonsense mutation (TGG [Trp116]-->TAG [Stop]) in CYP11B1 causes steroid 11 beta-hydroxylase deficiency.

Steroid 11 beta-hydroxylase deficiency (11 beta OHD), an autosomal recessive hereditary disease, accounts for 5-8% of cases of congenital adrenal hyperplasia. In this study, we carried out a molecular genetic analysis of CYP11B1 encoding steroid 11 beta-hydroxylase (P450c11) from a Japanese patient affected with this disease. Nucleotide sequence analysis of polymerase chain reaction-amplified products of the patient's genome revealed the occurrence of a stop codon in exon 2 due to a point mutation, TGG-->TAG (Trp116-->Stop). To further analyze the role of CYP11B2 encoding steroid 18-hydroxylase (P450c18) in the 11 beta OHD patient, CYP11B2 of the patient was also amplified and sequenced. In contrast to CYP11B1, there was no mutation in CYP11B2. Restriction fragment length polymorphism analysis indicated that the 11 beta OHD patient is homozygous and his unaffected parents are heterozygous for the mutation. When a cDNA corresponding to CYP11B1 of the 11 beta OHD patient was transfected into COS-7 cells, steroid 11 beta-hydroxylase activity was not detectable in mitochondria of the cells. These results demonstrate that intact P450c11 was not produced at all due to the nonsense mutation in CYP11B1 of the patient without any mutation in CYP11B2.

Adrenal Hyperplasia, Congenital↗
PubMed1993

Pineocytoma with intratumoral hemorrhage following ventriculoperitoneal shunt--case report.

A 58-year-old female with pineocytoma developed intratumoral hemorrhage after ventriculoperitoneal shunting for hydrocephalus. Neurological examination revealed Parinaud's sign and papilledema. Computed tomography and magnetic resonance (MR) imaging revealed a pineal neoplasm and obstructive hydrocephalus. Serum and cerebrospinal fluid levels of human chorionic gonadotropin, alpha-fetoprotein, carcinoembryonic antigen, and placental alkaline phosphatase were negative or within normal limits. MR images after the ventriculoperitoneal shunting disclosed intratumoral hemorrhage and markedly smaller ventricles. The tumor was totally removed via the occipital transtentorial approach and was diagnosed histologically as a pineocytoma with astrocytic differentiation. The tumor probably shifted away from the surrounding structures following the marked reduction in ventricular size after ventriculoperitoneal shunting, resulting in changed venous circulation in the tumor and the formation of intratumoral hematoma.

Brain↗
PubMed1993

[Transcranial Doppler sonography in acute intracranial hypertension model--usefulness of pulsatility index].

The authors studied intracranial hemodynamics in experimental animals (Macaca Fuscatus) with acute intracranial hypertension by use of transcranial Doppler (TCD) ultrasound. The blood mean flow velocity in the middle cerebral artery (MCA-FV) and pulsatility index (PI) was recorded using TCD ultrasound (TC2-64, EME) as in the clinical study. Acute intracranial hypertension was produced to determine the correlation of MCA-FV with intracranial pressure (ICP) and cerebral perfusion pressure (CPP) in 11 monkeys, and the correlation of PI with ICP and CPP in 7 monkeys. ICP was elevated by infusing 0.1-0.2 ml/min of saline into the balloon using infusion pump. ICP was raised until maximum level. Changes of MCA-FV, PI, ICP and CPP were evaluated until the CPP of 0mmHg. There was a significant correlation between MCA-FV and ICP (p < 0.01) as well as between MCA-FV and CPP (p < 0.01) in all 11 monkeys. There was also a significant correlation between PI and ICP (p < 0.01) and between PI and CPP (p < 0.01) in 7 monkeys. PI increased markedly when ICP was 80mmHg or greater or when CPP was 60mmHg or less. ICP was always above 80mmHg when PI was above 1.2. All PI values were above 1.0 when CPP was 40mmHg or less. Thus, we could not estimate the absolute values of ICP or CPP from MCA-FV and PI. It seems possible, however, to follow changes in intracranial hemodynamics at the time of increased ICP if MCA-FV and PI are measured continuously while paying attention to factors influencing MCA-FV.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

[Effect of rapid mannitol infusion on middle cerebral artery blood flow velocity and pulsatility index--a transcranial Doppler ultrasonography study in monkeys].

Hemodynamic changes immediately after the administration of mannitol were investigated in monkeys (Macaca Fuscata) using transcranial Doppler ultrasound (TC2-64) and were compared with those after CO2 loading. The CO2 loading group was hyperventilated to an end-tidal PCO2 of 36.5 +/- 2.21 and hypoventilated to an end-tidal PCO2 of 46.3 +/- 2.69. Mean flow velocity in the middle cerebral artery (MCA-FV), Pulsatility index (PI) and blood flow in the internal carotid artery (IC-BF) studies were performed twice before and after hypercapnea. In the Mannitol group, Mannitol (2 g/kg) was infused at a rate 20 to 30 ml/min. MCA-FV, PI, IC-BF and intracranial pressure (ICP) studies were performed twice before administration and 10 minutes after administration of Mannitol. In the Mannitol group (n = 8), MCA-FV and IC-BF and ICP increased significantly after administration of Mannitol (p < 0.005, p < 0.005, p < 0.025), but there was no significant difference in the PI. In the CO2 loading group (n = 15), MCA-FV and IC-BF increased significantly (both p < 0.005) and PI decreased significantly (p < 0.005). These results indicated that, in the presence of normal autoregulation without intracranial hypertension, there was no change in the resistance of the peripheral cerebral vessels, while a decrease in viscosity after administration of Mannitol caused an increase in cerebral blood flow. Hence, according to Poiseuille's law, peripheral vasoconstriction occurred in the early period after administration of Mannitol. This change was considered to be due to autoregulation of the cerebral vessels.

Animals↗