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T Kikuchi

Publications and source records attributed to T Kikuchi.

At least 559 records · Page 31Linked to original sources
PubMed1989

Effects of dietary vitamin E supplement on gracile axonal dystrophy (gad) mice.

We have studied the effects of dietary vitamin E supplement on the clinical signs and pathological changes in GAD (gracile axonal dystrophy) mice. The control diet contained 2 mg of dl-alpha-tocopheryl acetate (2 I.U.) and vitamin E-supplemented diet contained 58.5 mg of dl-alpha-tocopheryl nicotinate (50 I.U.), per 100 mg of feed. The diet was given to normal (gad/+) and GAD (gad/gad) mice from 21 to 130 days of age. During the feeding, there was no improvement in clinical signs in the GAD mice fed the vitamin E-supplemented diet. The gracile nucleus of the medulla oblongata and the gracile fascicules of the spinal cord were investigated for pathology at 130 days of age, and alpha-tocopherol was also assayed in the serum, liver, brain and spinal cord at that time. There were no pathological differences in the gracile nucleus and fascicules between the GAD mice fed the control and vitamin E-supplemented diet. The alpha-tocopherol levels in the serum and target organs in the control GAD mice were not significantly different from those in control normal mice, showing that GAD mice could absorb and transport alpha-tocopherol. In the supplemented GAD mice, no significant increases in alpha-tocopherol levels were observed in the liver, brain or spinal cord. Particularly, the percentage increase of alpha-tocopherol level in the liver of GAD mice was very low in comparison with that in normal mice, even though the liver can store vitamin E. Thus it may be that the capacity to store vitamin E is lowered in GAD mice. Further studies are needed to investigate in detail the vitamin E metabolism in the mutant mice.

Animals↗
PubMed1989

Quantitative assay of lentinan in human blood with the limulus colorimetric test.

A conventional limulus test detects not only endotoxin but also beta (1----3) glucan. Therefore, using a quantitative limulus test (the limulus colorimetric test) we studied the pharmacokinetics of lentinan, an antitumor beta (1----3) glucan, in the blood of 10 health volunteers and three patients with advanced gastric cancer. The calibration curve of lentinan in the human plasma was linear in the range of 0 to 100 ng/ml. When incubated with human plasma at 37 degrees C in vitro, lentinan had the recovery of almost 100% as compared to the initial concentration even after 60-min incubation, indicating the stability of lentinan in human plasma. When 1 mg of lentinan was intravenously administered over a 2 hr period, lentinan concentration reached the maximum levels (50-80 ng/ml) at the end of the drip infusion and decreased gradually thereafter. In the near future, the more appropriate modes of lentinan administration will be determined by further investigation of its kinetics in the human body.

Colorimetry↗
PubMed1989

Analysis of the promoter region of the cloned kanamycin resistance gene (kmr) from Streptomyces kanamyceticus.

The appropriate location and orientation of the kanamycin resistance gene (kmr) cloned on multicopy plasmids were determined by subcloning experiments. The transcription start site was identified by high-resolution S1 mapping and the kmr mRNA was shown to have a long leader of about 400 bp. An additional transcript upstream of the kmr gene was also detected, which ran in the opposite direction and overlapped 2 to 3 nucleotides with the kmr transcript. The presumptive promoter region of this physiologically unidentified RNA was similar to the Escherichia coli promoter consensus sequence both in the -10 and -35 regions, whereas the putative promoter region of the kmr gene exhibited sequence similarities in the -10 region to the promoters of the endoglycosidase H (endoH) and the viomycin phosphotransferase (vph) genes from Streptomyces.

Base Sequence↗
PubMed1989

[Properties of dental cyanoacrylate cement "FH" in the early period of setting].

The properties of dental cyanoacrylate cement "FH", which has protective and bacteriostatic effect on dental pulp, were compared with that of glass-ionomer cement. The operational properties such as setting time and consistency were good, but the mechanical properties as dental cement were a little inferior. These properties were affected definitely by temperature and humidity than the glass-ionomer cement, especially the influence of humidity was very high. However, the influence on bond strength was almost nothing, especially in the early period of setting. The factors affecting it could be very low disintegration. The bond strength for dentin after 24 hours the start of mixing of FH cement was much higher than that for enamel, but the strength rapidly decreased by thermal cycling between 4 degrees C and 50 degrees C in water.

Cyanoacrylates↗
PubMed1989

[Randomized-controlled study of treatment with UFT-MMC or UFT-ACR in advanced gastric cancer. Tohoku Study Group of Cancer Treatment for the Digestive Organs].

The effect of UFT-MMC- or UFT-ACR-therapy on the unresectable or recurrent gastric cancer was studied by a multicenter, randomized-controlled trial. All the patients who were randomly divided into the two groups were administered orally with 400 or 600 mg/day of UFT everyday. In addition, the UFT-MMC group was intravenously injected weekly for three weeks and then triweekly after six weeks with 6 or 8 mg/body of MMC, while the UFT-ACR group was intravenously injected with 20 mg/body of ACR for 5 serial-days every three weeks. Out of 88 cases registered, 75 (85.2%) were evaluable, consisting of 40 (31 complete cases) in UFT-MMC and 35 (27 complete cases) in UFT-ACR. There was no difference in various background factors between the two groups. PR, NC and PD was 10/31, 15/31 and 6/31 in the UFT-MMC group, whereas 0/27, 22/27 and 5/27 in the UFT-ACR group, respectively. The efficacy in the former group was higher, though not significant (U-test, p = 0.052), than that in the latter group. However, there was no difference in the 50% survival time (4.9 months in UFT-MMC vs. 5.4 months in UFT-ACR) of the either group.

Aclarubicin↗
PubMed1989

Effect of dietary polyamines and alpha-difluoromethylornithine on regulation of intestinal Na+/H+ exchanger.

Polyamines are compounds required for initiation of rapid cellular growth and differentiation in many cell types. Ornithine decarboxylase is the rate limiting enzyme in polyamine synthesis. Fasting and refeeding regulates the activity of ornithine decarboxylase and polyamine content in the intestinal tract. We tested the hypothesis that polyamines regulate cell growth via the Na+/H+ exchanger which is believed to be intimately involved in cell growth. Ileal Na+/H+ activity was therefore examined in control, fasted, refed fasted, and in rats given the specific inhibitor of ornithine decarboxylase alpha-difluoromethylornithine. A well-validated ileal brush border membrane vesicles for the study of Na+/H+ exchange activity was utilized. Fasting markedly decreased while refeeding stimulated Na+/H+ exchange activity at all times studied (P less than 0.05-0.001). Maximal uptake of Na+ at 5 min was 3.12 +/- 0.05, 2.5 +/- 0.05 and 2.22 +/- 0.05 nmol/mg protein in refed, control and fasted rats respectively. Kinetics of amiloride sensitive Na+/H+ exchanger showed a Vmax of 17.1 +/- 3.5, 8.0 +/- 0.64 and 4.7 +/- 1.1 nmol/mg protein per 5 s in refed fasted, control and fasted rats respectively Km values were not significantly different between the groups studied. 2% alpha-difluoromethylornithine given in the drinking water abolished the stimulation in Na+/H+ exchange activity in refed fasted rats. These results suggest a close relationship between polyamines and Na+/H+ activity in the intestinal mucosa of rats.

Animals↗
PubMed1989

[A case of the benign adrenal adenoma with remarkably high concentrations of deoxycorticosterone and 11-deoxycortisol].

The case was a 33-year-old woman with hypertension and hypokalemia, who presented depression of renin activity and the abnormal elevation of plasma deoxycorticosterone (DOC) and 11-deoxycortisol on laboratory tests. After admission, abdominal CT scan, 131I-adosterol scintigram and adrenal venogram revealed a tumor in the left adrenal, which histologically seemed to be benign. When the tumor was resected, blood pressure and all the biochemical data returned to normal range. DOC and 11-deoxycortisol levels in the tumor were abnormally elevated as compared with those in the normal adrenal tissue. These findings suggested that the abnormal elevation of hormone levels resulted from depression of 11 beta-hydroxylase. Though numerous adrenal tumors have been documented, we rarely encounter an apparently benign adrenal tumor that produces 2 kinds of hormones. This seemed to be the first case of benign adrenal tumor in which both DOC and 11-deoxycortisol were elevated.

17-Hydroxycorticosteroids↗
PubMed1989

[Tricuspid valve replacement in the true annulus of Ebstein's anomaly without involvement of atrioventricular conduction disturbance].

Two female patients with Ebstein's anomaly, aged 12 and 45 years, underwent new procedures of tricuspid valve replacement in the true annulus without involvement of atrioventricular conduction disturbance. The first patient had a relatively small atrialized right ventricle. A Dacron patch was sutured on the atrialized portion from the right ventricular side. Buttress stitches were placed on the whole of the atrialized ventricle except at the part of the His' bundle. A porcine valve was sutured in the true annulus of the tricuspid valve and on the top of the patch. The second patient had a fairly large atrialized ventricle, and plication was made only in the inferior part of the atrialized ventricle form the coronary sinus. A porcine valve was sutured in the true tricuspid annulus except at the part of Koch's triangle, where the porcine valve was placed on the false annulus.

Bioprosthesis↗
PubMed1989

[Change of blood lentinan level in patients with advanced cancers].

A conventional limulus test can detect not only endotoxin but also beta(1----3) glucan. Therefore, with a quantitative limulus test, the limulus colorimetric test, we studied the pharmacokinetics of lentinan, an antitumor beta(1----3) glucan preparation, in the blood of 10 healthy volunteers and 20 patients with advanced cancers. The calibration curve of lentinan in the human plasma was linear in the range of 0 to 100 ng/ml. Two mg of lentinan was administered once a week and blood samplings for the measurement were done immediately before the next lentinan administration to document trough-levels serially at a week interval. Trough-levels tended to rise gradually and showed a rapid elevation between 4 and 8 weeks after beginning of administration. This phenomenon may correlate closely with the antitumor effect of lentinan and, therefore, deserves further investigations.

Antineoplastic Agents↗
PubMed1989

[Intra-arterial infusion chemotherapy with [Sar1, Ile8] angiotensin II in bladder cancer].

Twenty patients with bladder cancer were treated with intra-arterial infusion chemotherapy using CDDP and ADM in combination with [Sar1, Ile8] angiotensin II. A catheter was introduced into internal iliac artery by Seldinger's technique, and 100 mg of CDDP, 50 mg of ADM and 1 mg of [Sar1, Ile8] angiotensin II were infused through the catheter for 40 minutes. CR was observed in 8 of 20 patients. PR in 11 and NC in 1. Therefore, the response rate (CR + PR) was 95% (19/20). Side effects were generally mild and consisted of leukopenia, nausea, vomiting, diarrhea, alopecia, skin pigmentation and headache. Catheter-related complications were not observed. This study demonstrated that intra-arterial infusion chemotherapy with CDDP and ADM in combination with [Sar1, Ile8] angiotensin II was extremely effective in treating patients with bladder cancer.

1-Sarcosine-8-Isoleucine Angiotensin II↗
PubMed1989

The role of cytokines in chondrocyte mediated cartilage degradation.

Articular chondrocytes cultured in the presence of recombinant human interleukin 1 alpha (rhIL-1 alpha) or recombinant human tumor necrosis factor alpha (rhTNF alpha) caused increased production of the latent metalloproteinase (collagenase and caseinase) and the proteoglycan release from cartilage. The existences of IL-1 and TNF alpha in the chondrocytes of human articular cartilage were also shown by immunohistochemical staining using polyclonal antibodies. Furthermore, chondrocyte was found to be a producer of interleukin 6 (IL-6), known as a pleiotropic cytokine and thought to be an important mediator of the cell interactions in arthritis. In addition, the production of IL-6 was also shown to be stimulated by rhIL-1 alpha or rhTNF alpha. From our findings, we suggest there exists a very complicated autocrine control system of chondrolysis by the chondrocyte itself.

Animals↗
PubMed1989

[The role of urine pH in the occurrence of phosphaturia].

The density of calcium phosphate and the pH were determined in 15 postprandial urine specimens with heavy precipitation of amorphous calcium phosphate, that is phosphaturia, collected from 5 patients with calcium urolithiasis (stone-formers) and 3 patients with no known urological disease (controls). Phosphaturia, not related to urinary tract infection or administration of alkalinizing agents, was found repeatedly at our outpatient clinic in these patients. The correlative relationship was not confirmed between the density of calcium phosphate and the pH. The concentration of calcium and phosphorus was also determined in 10 urine specimens with phosphaturia. The concentration of phosphorus was correlated significantly with the pH (r = -0.775, p less than 0.01), although the concentration of calcium was not correlated with the pH. The pH of 11 urine specimens with phosphaturia from the controls was 7.51 +/- 0.31 (mean +/- S.D.) and the pH of 18 urine specimens with phosphaturia from the stone-formers was 6.81 +/- 0.34. The pH was significantly lower in the urine specimens from the stone-formers than in those from the controls (p less than 0.01). We have noted that the occurrence of phosphaturia depends not only on the urinary pH but on the concentration of phosphorus. It is interesting that phosphaturia often occurs in urine specimens with a pH below 7 in stone-formers.

Adult↗
PubMed1989

[Surgical indication to deep-seated arteriovenous malformation].

The natural history of cerebral arteriovenous malformation (AVN) is still a subject of dispute. In the case of deep seated AVM ruptures, the problem is more serious because the hemorrhages often give rise to severe disability or death, depending on their location. Total extirpation of the nidus is fundamentally the best choice for treatment of AVM. It is never acceptable, however, to allow a persistent post operative deficit. Forty-seven cases of deep AVM were encountered in the Tokyo Jikei University Hospital. Total extirpation of the nidus was successful in 32 cases, while no surgery was undertaken in 15. Up to the present time we have taken three risk factors into condition in judging the indications for deep seated AVM surgery: the size of the nidus, the position of the nidus, and the pattern of demarcation around nidus, as shown on CT scan. When the nidus is bordered by a hemorrhage, cyst, or ventricular wall, dissection of the nidus is facilitated and injury to adjacent brain tissue is minimized, and this is why we included profound demarcation around the nidus as the third factor. We then determined grade of risk with respect to each factor, and counted a risk score in each case. The long-term result was judged by the response to questionnaires. Of the 15 patients who did not undergo surgery, four died on account of rebleeding. The longer the patient having deep AVM survived, the more likely the occurrence of fatal rebleeding. Of the 32 patients operated on, two died immediately after surgery, while 23 survived in an improved state or without any aggravated neurological deficit.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Prediction of the location of structural domains in globular proteins.

The location of structural domains in proteins is predicted from the amino acid sequence, based on the analysis of a computed contact map for the protein, the average distance map (ADM). Interactions between residues i and j in a protein are subdivided into several ranges, according to the separation [i-j[ in the amino acid sequence. Within each range, average spatial distances between every pair of amino acid residues are computed from a data base of known protein structures. Infrequently occurring pairs are omitted as being statistically insignificant. The average distances are used to construct a predicted ADM. The ADM is analyzed for the occurrence of regions with high densities of contacts (compact regions). Locations of rapid changes of density between various parts of the map are determined by the use of scanning plots of contact densities. These locations serve to pinpoint the distribution of compact regions. This distribution, in turn, is used to predict boundaries of domains in the protein. The technique provides an objective method for the location of domains both on a contact map derived from a known three-dimensional protein structure, the real distance map (RDM), and on an ADM. While most other published methods for the identification of domains locate them in the known three-dimensional structure of a protein, the technique presented here also permits the prediction of domains in proteins of unknown spatial structure, as the construction of the ADM for a given protein requires knowledge of only its amino acid sequence.

Adenylate Kinase↗
PubMed1988

Prediction of the packing arrangement of strands in beta-sheets of globular proteins.

A method is proposed for predicting the adjacency order in which strands pack in a beta-sheet in a protein, on the basis of its amino acid sequence alone. The method is based on the construction of a predicted contact map for the protein, in which the probability that various residue pairs are close to each other is computed from statistically determined average distances of residue pairs in globular proteins of known structure. Compact regions, i.e., portions of the sequence with many interresidue contacts, are determined on the map by using an objective search procedure. The proximity of strands in a beta-sheet is predicted from the density of contacts in compact regions associated with each pair of strands. The most probable beta-sheet structures are those with the highest density of contacts. The method has been tested by computing the probable strand arrangements in a five-strand beta-sheet in five proteins or protein domains, containing 62-138 residues. Of the theoretically possible 60 strand arrangements, the method selects two to eight arrangements as most probable; i.e., it leads to a large reduction in the number of possibilities. The native strand arrangement is among those predicted for three of the five proteins. For the other two, it would be included in the prediction by a slight relaxation of the cutoff criteria used to analyze the density of contacts.

Bacterial Proteins↗
PubMed1988

Prediction of probable pathways of folding in globular proteins.

A method is described for the prediction of probable folding pathways of globular proteins, based on the analysis of distance maps. It is applicable to proteins of unknown spatial structure but known amino acid sequence as well as to proteins of known structure. It is based on an objective procedure for the determination of the boundary of compact regions that contain high densities of interresidue contacts on the distance map of a globular protein. The procedure can be used both with contact maps derived from a known three-dimensional protein structure and with predicted contact maps computed by means of a statistical procedure from the amino acid sequence alone. The computed contact map can also be used to predict the location of compact short-range structures, viz. alpha-helices and beta-turns, thereby complementing other statistical predictive procedures. The method provides an objective basis for the derivation of a theoretically predicted pathway of protein folding, proposed by us earlier [Tanaka and Scheraga (1977) Macromolecules 10, 291-304; Némethy and Scheraga (1979) Proc. Natl. Acad. Sci., U.S.A. 76, 6050-6054].

Adenylate Kinase↗