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H Kikuchi

Publications and source records attributed to H Kikuchi.

At least 577 records · Page 32Linked to original sources
PubMed1990

Study of the elastic skeleton of intracranial arteries in animal and human vessels by scanning electron microscopy.

We studied the elastic skeleton of major cerebral arteries in rats, monkeys, and one human using scanning electron microscopy after hot formic acid extraction followed by freeze-drying. For comparison, we also examined the thoracic aorta and femoral artery of rats. The cerebral arteries of rats had one distinct internal elastic lamina connected to the thin adventitia with sponge-like medial elastic tissue. This internal elastic lamina had fenestrations, which we found to be less frequent in cerebral arteries than in extracranial arteries, and fold-like protrusions into the lumen. This finding has not been recognized before. Such protrusions were more prominent in cerebral arteries than in extracerebral arteries. At the apical intimal pad, the internal elastic lamina appeared to be continuous, making a honeycomb-like structure. The folds and fenestrations were numerous at the apex. There were no essential differences among species. Our study shows that the internal elastic lamina is not a simple sheet but part of the complicated architecture of the elastic tissue of the vessel wall. These differences in the elastic skeleton, including fenestrations and fold-like structures, in various sites of different arteries may explain the development of various localized vascular diseases.

Animals↗
PubMed1990

Replacement of L-T4 suppository in MMI treated rabbits.

L-T4 suppositories containing 50, 100 or 200 micrograms of L-T4 were given to rabbits treated with MMI. The serum T4 gradually increased within 3.5 and 6.5 hours following the use of 100 and 200 micrograms of L-T4 suppositories, respectively, without an acute increase in serum T3. The increase in serum T4 continued up to 48 hours. The area under the curve (AUC) for serum T4 was evidently dose-dependent. It is concluded from these results that the T4 suppository will be useful as a replacement therapy for patients with hypothyroidism.

Animals↗
PubMed1990

Complementary DNA sequence of 3-methylcholanthrene-inducible P-450 from the rat lung.

Cytochrome P-450MC was induced in pulmonary microsomes of 3-methylcholanthrene-treated rats and also at low level in that of isosafrole-treated rats. Cytochrome P-450d was not detected in the lungs of 3-methylcholanthrene- or isosafrole-treated rats by the method of Western blot analysis with a polyclonal antibody raised against cytochrome P-450c which is equally effective against P-450d, nor by the method of Northern hybridization probed with pcP450mc3 (P-450d probe). Complementary DNA of P-450MC was isolated from rat pulmonary cDNA library and the nucleotide sequence of pulmonary cDNA was compared with that of hepatic P-450c cDNA reported by Yabusaki et al. There was no gross change in nucleotide sequences of cDNA between pulmonary P-450MC and hepatic P-450c.

Amino Acid Sequence↗
PubMed1990

Repetitive sequences in the rat genome that have cleavage sites for the restriction endonuclease Taq I.

A cleavage of rat DNA with restriction endonuclease Taq I produced at least 8 discrete bands. One of the bands, 0.29 kilobase pairs (kb) long, was isolated and cloned in plasmid. The hybridization of this fragment to genomic DNA digested with Taq I showed 1.6 kb, 1.2 kb and 0.29 kb band in a smear hybridization signal. A repetition of the DNA sequence of this fragment was about 12,500 copies/haploid genome of both Buffalo and Sprague-Dawley rats by the Cot-hybridization analysis. Four independent clones of 0.29 kb Taq I fragment share high homology (97%).

Animals↗
PubMed1990

Red blood cells are essential for late vasospasm following experimentally induced subarachnoid hemorrhage in dogs.

The in vivo spasmogenic activity of various blood components was examined in dogs. Each blood fraction was injected into the cisterna magna at 0.5 or 1.0 ml/kg body weight, after the removal of 0.5 ml/kg body weight of cerebrospinal fluid, and vertebral angiography was then performed. Whole blood induced both early and late arterial spasm. Platelet-rich and platelet-poor plasma produced only early spasm, and no arterial narrowing was observed on days 1, 3, and 7 after injection. On the contrary, intracisternal injection of washed red blood cells (0.5 ml/kg body weight) produced no arterial narrowing for 6 hours after injection and induced moderate arterial narrowing on days 1, 3, and 7 after injection. Hemolysate (a 10-gm/dl concentration of hemoglobin) produced prolonged monophasic arterial narrowing after injection. These results imply that red blood cells are required for late, prolonged arterial narrowing after experimental subarachnoid hemorrhage.

Animals↗
PubMed1990

Multiple intracranial metastases following malignant evolution in recurrent pleomorphic adenoma of the lacrimal gland--case report.

A 54-year-old female presented with multiple intracranial metastases following malignant transformation in the third recurrence of pleomorphic adenoma of the left lacrimal gland, 25 years after the first surgical treatment. The preoperative computed tomography and magnetic resonance imaging demonstrated direct invasion of the orbital tumor into subdural and epidural spaces in the ipsilateral frontotemporal region and also an intracerebral metastasis in the ipsilateral parietal lobe. Histological examination of the surgical specimen revealed features of poorly differentiated adenocarcinoma, suggesting carcinomatous changes. The relevant literature is reviewed.

Adenocarcinoma↗
PubMed1990

Glucose consumption and rate constants for 18F-fluorodeoxyglucose in human gliomas.

To investigate the value of direct measurement of the rate constants by performing 18F-labeled fluorodeoxyglucose (FDG) studies of glucose consumption in human gliomas in vivo, a kinetic method with 3- and 4-parameter rate constant models for FDG uptake was used to analyze data from dynamic scans obtained by positron emission tomography after injection of FDG into 14 patients with glioma. The results were compared with those obtained by the autoradiographic method using 3- and 4-parameter rate constant models. There were no significant differences in the glucose consumption calculated by the four different methods both in the gliomas and in the contralateral intact cortex. It was found that the rate constant k4* could be neglected in calculation of glucose consumption in gliomas as well as in the contralateral intact cortex. The rate constant k3*, an index of hexokinase function, was higher in malignant gliomas than in benign gliomas and was close to that in the contralateral cortex. This study indicates that the 3-parameter autoradiographic method, which is the most common one used in clinical practice, is reliable for the calculation of glucose consumption in human gliomas. Furthermore, direct measurement of the regional rate constants for FDG by the kinetic method was found to be useful for evaluation of the biochemical and physiological characteristics of human gliomas in vivo.

Adult↗
PubMed1990

Intracranial metastasis of a spinal cord astrocytoma--case report.

The authors report a case of cerebral metastasis from a spinal cord astrocytoma. The first metastatic tumor was controlled by radiation therapy. A second metastatic brain tumor was detected 2 years later, but attempts to control it through subtotal removal and chemotherapy failed. Metastasis from a spinal cord tumor to the brain is a rare event.

Astrocytoma↗
PubMed1990

[Molecular analysis of relationship between oncogene (N-myc and c-src) expression and major histocompatibility complex antigen gene expression in mouse neuroblastoma lines].

The authors have investigated the relationship between oncogene (N-myc and c-src) expression and major histocompatibility complex (H-2 in the mouse) antigen gene expression at the molecular levels, by using mouse neuroblastoma sublines (NB-1 and NB-V). Fluorescence-activated cell sorter analysis showed that NB-1 cells exhibited positive expression to H-2 Kk, H-2 Dd, and beta-2-microglobulin, while NB-V cells were negative to all three antigens. It was found that dimethyl sulfoxide (DMSO) had a capacity to increase an H-2 class I antigen expression on NB-1 cells, whereas no change was observed on NB-V cells after DMSO treatment. Molecular analysis with deoxyribonucleic and ribonucleic acid (RNA) blot hybridization and immunoprecipitation revealed that the enhancement of H-2 antigen expression on NB-1 cells was modulated at the transcriptional control of the H-2 gene. In contrast, negative H-2 antigen expression on NB-V cells was caused by block at the level of glycosylation of the H-2 heavy chain, although an increase in messenger RNA of the H-2 gene was induced after DMSO treatment. There was neither amplification nor rearrangement of N-myc and c-src oncogenes in either neuroblastoma subline. Nuclear run-on transcription assay revealed that the N-myc gene was post-transcriptionally down-modulated by DMSO, whereas the c-src gene was transcriptionally up-regulated. It was thus suspected that N-myc and c-src might be directly associated with cellular proliferation and differentiation in neuronal tumors and that in vivo tumorigenicity could be regulated by the control mechanism of oncogene expression in relation to H-2 gene expression on tumor cells.

Animals↗
PubMed1990

[Cytotoxic effector mechanism and genetic control of non-immunized hybrid resistance to mouse T cell lymphoma transplanted outside and inside the brain].

A Moloney virus-induced T cell lymphoma, YAC-1, derived from A/Sn (H-2a) inbred mouse origin, was tested for hybrid resistance (HyR) after subcutaneous (s.c.) or intracerebral (i.c.) tumor cell inoculation into syngeneic and semi-syngeneic mice. The F1 hybrids (H-2a/b) between A/Sn and C57BL/6 mice more strongly resisted the s.c. inoculation of 10(6) and 5 x 10(5) cells than did syngeneic recipients. In contrast, no HyR to the i.c. inoculation of 10(4) and 10(3) cells was seen in the F1 hybrid mice. Natural killer (NK) cell activity was much higher in F1 hybrids than in syngeneic mice. 125I-iododeoxyuridine-labeled YAC-1 cells were more efficiently eliminated from the highly resistant F1 hybrids than from the parental strain in both 4 and 18 hour in vivo rejection assays via intravenous (i.v.) and s.c. injection, respectively. The remaining radioactivity of the brain, however, did not differ between these mice. Thus, there was a correlation between the in vivo resistance of F1 hybrid mice to challenge s.c. inoculation of parental tumors and their expression of lymphocyte-mediated natural cytotoxicity in vitro against those tumors. T cell depletion by thymectomy followed by irradiation and fetal liver reconstitution did not abrogate the s.c. HyR against YAC-1, whereas NK cell depletion by i.v. administration of anti-asialo-GM1 antibodies resulted in the disappearance of the resistance. Furthermore, genotypic study segregating (A/Sn x C57BL/6) F1 x A/Sn backcross mice indicated that the s.c. HyR might be attributable primarily to heterozygosity within the H-2 complex.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Vascular relaxation properties of calcitonin gene-related peptide and vasoactive intestinal polypeptide in subarachnoid hemorrhage.

The vascular relaxation effects of calcitonin gene-related peptide (CGRP) and vasoactive intestinal polypeptide (VIP) on the dog basilar artery after experimentally produced subarachnoid hemorrhage (SAH) were examined in vitro by an isometric tension recording method. Both CGRP and VIP induced dose-dependent relaxations in ring segments of the intact basilar artery of control dogs. The vasorelaxant action of CGRP was more potent than that of VIP. The single-injection model of SAH was produced by injection of fresh autologous arterial blood (1 ml/kg body weight) into the cisterna magna on Day 0 of the post-SAH period, and the double-injection model was produced by two injections of blood (0.5 ml/kg each) on Days 0 and 2. Narrowing of the basilar arteries on vertebral angiograms was most prominent on Day 3 or 7 in the single- or double-injection model, respectively. Relaxation of the basilar artery induced by CGRP and VIP was to some extent decreased on Days 3 and 7 of the post-SAH period in the single-injection model, and on Days 7 and 14 in the double-injection model. However, the vasorelaxant effects of CGRP and VIP were significantly enhanced on Day 14 of the post-SAH period in the single-injection model, and on Days 28 and 42 in the double-injection model. Subsequently, these effects returned to control levels by Days 28 or 63 in the single- or double-injection model, respectively.

Animals↗
PubMed1990

Effects of blood coagulation factor XIII on the development of experimental cerebral aneurysms in rats.

Pathological and experimental studies have shown that cerebral aneurysms develop in part as a result of injury to the blood vessel wall. One of the peculiar aspects of aneurysm development is a defective proliferative or healing response to such injury. To examine this phenomenon, blood coagulation Factor XIII, which is known to enhance the healing process of wounds in general, was given to rats to induce experimental cerebral aneurysms. The rats were subjected to ligation of one common carotid artery and induction of hypertension, and were fed beta-aminoproprionitrile. Two weeks thereafter, Factor XIII was injected intravenously daily for 5 days (10 U/100 gm body weight/day). Twelve days after the start of Factor XIII injections, the rats were sacrificed and examined under light and electron microscopy. In seven of 12 bifurcations which developed small aneurysms, prominent intimal thickening was observed in the aneurysm lumen. In the most advanced cases, the aneurysm lumen was completely filled with proliferated smooth-muscle cells and collagen. In five of nine bifurcations that showed no aneurysm development, apparent intimal thickening was found at the site where aneurysms might be expected to grow. In the group of rats studied for induction of cerebral aneurysms but not given Factor XIII, none of 11 bifurcations with or without aneurysms showed such intimal thickening. The results indicated that the proliferative response at the sites of aneurysm development was modified by exogenous Factor XIII.

Animals↗
PubMed1990

Transsphenoidal approach to infrasellar tumors involving the cavernous sinus.

The authors review their 2-year experience with a rhinoseptal transsphenoidal approach to skull-base tumors of various pathologies involving both the sphenoid and cavernous sinuses. Eight patients with cranial nerve palsies attributable to compression of the contents of the cavernous sinus and/or optic canal are included in this report. Among these patients, a total of 17 cranial nerves were affected. Postoperative normalization was achieved in eight nerves, significant improvement in seven nerves, and no improvement in two nerves. There were no operative complications of aggravation of cranial nerve palsies in this series. In spite of the limited operating field, the results demonstrate the effectiveness and safety of this approach. The authors recommend that this approach be considered before more aggressive surgery is undertaken.

Adult↗
PubMed1990

[Establishment and characterization of human cholaginocarcinoma, MEC, producing carbohydrate antigen 19-9].

A new tumor cell line MEC was established from pleural effusion of a patient of cholaginocarcinoma. In tissue culture, the cell line grew in the sheet of variant cells and showed the epithelial-like pattern. Histologically, the cell line almost showed the same pattern as those in bile and preural effusion from the patient. Electron microscopic observation of this cell line showed the irregular microvilli on the surface of the cell and the desmosome between cells. The doubling time of the cell line was 40.8 hours. Chromosome counts ranged from 61 to 86. The cell line had 9 marker chromosomes and some variant chromosomes. The cell line was transplanted into the subcutaneous of nude mice and formed the tumor. It showed the moderately differentiated tubular adenocarcinoma the same pattern as the primary tumor. We have recognized the producing and releasing of CA19-9 in the serum from the tumor bearing nude mouse and supernate of the medium as the serum from the patient. The presentation of CA19-9 in the cytosol of the cell line and the tumor cells of nude mouse was recognized in Avidin-Biotin-Peroxidase Complex in immunoloperoxidase techniques. The cell line can grow in serum-free medium. On September, 1990, the cell line has been maintained from 70 passages during about 800 days.

Adenoma, Bile Duct↗
PubMed1990

[Thrombotic thrombocytopenic purpura (TTP) in which plasmapheresis was ineffective but vincristine slow infusion therapy was effective with long-term remission].

A 38-year old female patient with thrombotic thrombocytopenic purpura (TTP) did not respond to plasmapheresis and treatment with corticosteroids and antiplatelet agents but did respond to subsequent high-dose gamma-globulin therapy and vincristine slow infusion therapy. Remission, thought to be due to vincristine, was achieved. The administration schedule of vincristine was 1 or 2 mg once a week by intravenous drip infusion over a period of 6 to 8 hr. Improvement tended to be seen after the 6th administration, and remission was achieved after the 12th administration (total dose: 15 mg), and continues to the time of this writing. In this case, it was thought that vincristine inhibited a certain excessive reaction in the process of PAIgG-related platelet consumption. We conclude that vincristine should be administered at least 5 to 6 times, and the therapeutic method should be established based on the experience in a larger number of clinical cases.

Adult↗
PubMed1990

A comparative study on reductive dehalogenation of halothane in liver, kidney and lung of the rabbit.

The contents of cytochrome P-450 (P-450) and cytochrome b5, and the activity of NADPH-cytochrome c reductase and the reductive metabolites of halothane, 2-chloro-1, 1-difluoroethylene (CDE) and 2-chloro-1, 1, 1-trifluoroethane (CTE) were measured in microsomes from the liver, kidney and lung of phenobarbital (PB) pretreated and untreated Japanese white strain rabbits. Microsomal P-450 levels in the liver, kidney (renal cortex) and lung of the rabbits were 1.91 +/- 0.35, 0.19 +/- 0.04 and 0.42 +/- 0.11 nmol/mg protein (mean +/- SD), respectively. In vivo phenobarbital pretreatment (PB-pretreatment) increased the content of P-450 to 2.95 +/- 0.40 nmol/mg protein (154%) in the liver and to 0.40 +/- 0.11 nmol/mg protein (211%) in the kidney, but had little effect in the lung. The activity of CDE formation was 0.72 +/- 0.10, 0.08 +/- 0.04 and 0.03 +/- 0.01 nmol/mg protein/min in the liver, kidney and lung, respectively. PB-pretreatment enhanced the activity of CDE formation to 1.59 +/- 0.49 nmol/mg protein (221%) in the liver, and to 0.29 +/- 0.16 nmol/mg protein/min (363%) in the kidney, but showed little enhancement in the lung. The activity of CTE formation was 1.30 +/- 0.19, 0.12 +/- 0.04 and 0.09 +/- 0.02 nmol/mg protein/min, in the liver, kidney and lung, respectively. PB-pretreatment enhanced the activity of CTE formation to 1.80 +/- 0.44 nmol/mg protein/min (138%) in the liver, but caused only slight enhancement in the kidney and lung. PB-pretreatment markedly enhanced the activity of CDE formation in the kidney. The authors conclude that cytotoxicity by reductive dehalogenation of halothane is possible not only in the liver but also in the kidney with PB-pretreatment.

Animals↗
PubMed1990

Effects of in vivo pretreatment with various barbiturates on anaerobic halothane metabolism in rat liver microsomes.

The effects of in vivo pretreatment with phenobarbital (PB), thiopental (TP), thiamylal (TA), pentobarbital (PT), and secobarbital (SB) on hepatic microsomal enzymes, and the effects on anaerobic halothane dehalogenation, aminopyrine N-demethylation, and aniline hydroxylation in the microsomes were studied in male Wistar rats. Three hundred twenty mumol/kg (0.1 ml) of PB, TP, TA, PT, SB, or 0.1ml of 0.9% saline were administered daily, intramuscularly, for periods of one day up to ten days. Daily administration of PB, TP, TA, or PT induced cytochrome P-450, NADPH-cytochrome P-450 reductase and/or cytochrome b5. However, administration of SB did not induce these enzymes. The potency of these enzyme inductions ranged in descending order as follows: PB, TP, TA, and PT. After five days of daily administration of PB, TP, or TA, the production of the anaerobic halothane metabolite, CDFE, increased to 187%, 134%, and 130% of the control, respectively. The production of another halothane metabolite, CTFE, likewise increased to 197%, 168%, and 163%. However, pretreatment with PT or SB had no effect on anaerobic halothane dehalogenation. Aminopyrine N-demethylation also increased after five days of daily administration of PB, TP, and TA. However, aniline hydroxylation decreased after five days of daily administration of TA. Other barbiturates had no effect on aniline hydroxylation. In this study we showed that whereas PT and SB did not enhance anaerobic halothane dehalogenation, PB, TP and TA did. We conclude that not only PB, and also TP and TA, may be enhancing factors in halothane hepatotoxicity. We recommend that, if barbiturates are necessary, SB and PT be used in the preadministration of halothane anesthesia.

Anaerobiosis↗