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K Ikejiri

Publications and source records attributed to K Ikejiri.

At least 37 records · Page 2Linked to original sources
PubMed1990

Functional analysis of multiple promoters of the rat insulin-like factor II gene.

We have characterized the multiple promoters of the rat insulin-like growth factor II (rIGFII) gene by in vivo transient expression assay using a series of deletion mutant templates. Among the four promoters (P1, P2, P3 and P6), two (P2 and P3) showed relatively strong promoter activities compared with the other two. One of the four promoters, P2, was further characterized by gel band-shift and footprinting analysis using HeLa cell nuclear extract, showing two retarded bands and at least one protected sequence stretch. The results indicated that P2 has a very simple structure like P3, and consists of no more than 141 base-pairs (bp) including a TATA box and two GC core hexanucleotides. Promoter strength shown by in vivo transient expression in different cell types failed to explain the differential employment of P2 and P3 in these cells, suggesting the involvement of other regulatory mechanisms that might operate only in the native state.

Animals↗
PubMed1990

[A case report of advanced gastric cancer remarkably responding to mitomycin C, aclacinomycin A, SF-SP and lentinan combination therapy].

A 63-year-old female diagnosed as inoperable gastric cancer was treated with combination immunochemotherapy of Mitomycin C, Aclacinomycin A, SF-SP and Lentinan. In this case, the tumor directly invaded the pancreas and the peritoneal dissemination, metastasis to the para-aortic lymph nodes and Virchow's metastasis were identified. As the result of this therapy, the primary tumor was remarkably reduced in size. The subjective symptoms and the metastasis of the para-aortic lymph nodes and Virchow's metastasis disappeared. The side effect was only mild thrombocytopenia.

Aclarubicin↗
PubMed1990

Structural dissimilarity in insulin-like growth factor II genes of the rat and the human.

A comparison of insulin-like growth factor II(IGFII) genes revealed the lack in the rat genome of a transcriptional system identified in human IGFII gene, h1-h2-h3. Complete deletion was, however, restricted to the h1 region, while the h2 and h3 sequences were conserved in a nearly intact form and in a highly deviated one, respectively. Meanwhile, the human genome contained a region highly homologous to the rE1 sequence, a rat-specific leader exon. These results indicate that the IGFII genes of these species were derived from a common ancestral gene having, together with two other common leader exons, rE2 (h4) and rE3 (h4B), four leader exons, and that the human-specific leader exon h1 sequence was not newly acquired in the human genome but was deleted from the rat genome after speciation.

Animals↗
PubMed1989

Multiple polyadenylation sites in a large 3'-most exon of the rat insulin-like growth factor II gene.

The rat insulin-like growth factor II (rIGFII) gene produces, in addition to three major mRNA species 3.6 kilobases (kb), 4.6 kb and 3.8 kb in length which represent transcripts from three independent leader-exons, multiple smaller-sized products that distribute broadly in the 1-3 kb region on Northern blots. Structural constituents of these RNAs were analyzed by hybridization with region-specific probes prepared from the entire rIGFII genome. Most of these shorter RNAs contained both 5'-untranslated and coding regions, but only parts of the 3'-untranslated region. At least nine protected sites were mapped within a single 3'-most exon E6 by S1 nuclease analysis. Some but not all of these sites were associated with the upstream polyadenylation signal, AATAAA, or its variants. Since none of the shorter subspecies contained intronic sequences, aberration in splicing is not involved in their generation. Thus, the main parts of submature materials are a collection of discrete species of RNAs, most, if not all, of which are produced by alternative polyadenylation site selection.

Amino Acid Sequence↗
PubMed1988

Reactivation of rat insulin-like growth factor II gene during hepatocarcinogenesis.

The insulin-like growth factor II (rIGFII) is a mitogenic polypeptide, the expression of which is high in most rat tissues during embryonic development, yet is barely detectable in adult tissues except for some of neurogenic origin. The gene is present as a single copy in the genome but has three alternative leader exons, E1, E2 and E3, thereby with three independent transcriptional promoters. We analysed the expression of rIGFII and the relative efficiency of each promoter in hepatocarcinogen-treated livers, primary hepatomas and established hepatoma lines. The E3-specific product was first detected after 6 weeks of 3'-methyl-4-dimethylaminoazobenzene treatment and those of E1 and E2 also after 9 weeks. The levels gradually increased according to the sum of the treatment period, but reactivation was nil in the regenerating liver. Consistently high levels of expression were observed in all primary tumors, but the relative promoter activity varied with the tumor. The significance of rIGFII reactivation was discussed in the light of the hepatocarcinogenesis.

Animals↗
PubMed1987

Insulinotropic effects of vanadate.

Vanadium compounds are known to affect multiple membrane and cytosolic phosphoenzymes from various tissues; the most characterized effect is the inhibition of Na+-K+-ATPase. Since we previously reported that immunoreactive insulin (IRI) secretagogues tend to inhibit rat islet cation-dependent ATPases, we examined the effects of sodium vanadate on rat IRI secretion from incubated and perifused rat islets. In the presence of 2.4 mM Ca2+, vanadate (10(-3) M) induced biphasic IRI secretion with a background glucose of 100 mg/dl. In the absence of extracellular Ca2+, IRI released from incubated islets by vanadate at 100 and 300 mg/dl glucose was doubled and tripled, respectively. Furthermore, this stimulatory effect was completely abolished by known inhibitors of IRI release such as somatostatin, epinephrine, and diphenylhydantoin. Although we found the expected dose-dependent inhibition by vanadate of islet membrane Na+-K+-ATPase activity, the mechanism of action of vanadate on IRI secretion remains unknown. Vanadate probably interacts in a complex fashion with different islet phosphoenzymes and may prove to be a useful probe to further unravel the mechanisms leading to insulin secretion.

Animals↗
PubMed1986

Superficial spreading esophageal cancer controlled by hyperthermo-chemo-radiotherapy: a case report.

Hyperthermo-chemo-radiotherapy (HCR) was prescribed for a patient with superficially spreading esophageal cancer, since severe lung dysfunction presented too great a surgical risk. Viable cancer cells completely disappeared after HCR and 8 months later, at this writing, the patient is living in good condition. Conservative treatment with HCR for patients with esophageal cancer is effective for carefully selected patients.

Aged↗
PubMed1980

Clinical study of niceritrol on serum lipids in the treatment of hyperlipidemia.

The effects of niceritrol, a nicotinic acid derivative, on the levels of HDL-cholesterol (HDL-Ch) and a mixture of VLDL- and LDL-Ch (VLDL- + LDL-Ch) were studied in hyperlipidemic patients. Serum total cholesterol (sTC) and serum triglyceride (sTG) were significantly reduced during niceritrol administration. Lipoprotein electrophoresis showed that niceritrol increased the alpha:beta ratio. HDL-Ch showed a significant increase of 12.5% by the 16th week of therapy. This increase was more marked in patients with lower pre-treatment HDL-Ch levels and significant in patients whose pre-treatment sTG levels were in excess of 200 mg/dl. Females displayed higher pre-treatment HDL-Ch levels (38.5 mg/dl) than males (30.6 mg/dl). However, niceritrol increased HDL-Ch significantly in both groups. At 16 weeks, the VLDL- + LDL-Ch level showed a significant decrease of 9.2%; the HDL-Ch:VLDL + LDL-Ch and HDL-CH:sTC ratios were significantly increased throughout niceritrol administration. Niceritrol is thought to be effective in preventing the development and progression of atherosclerosis because it raises the level of anti-atherogenic HDL-Ch and lowers the level of atherogenic VLDL- + LDL-Ch.

Cholesterol↗
PubMed1980

Massive intestinal bleeding in hemangiomatosis of the duodenum.

A 33-year-old male was admitted to Takano Hospital with fainting spell and diaphoresis due to massive terry stool. He had been working and in good health until 2 days before admission. Urgent duodenal endoscopy disclosed hemorrhage from an angiomatous lesion of the duodenum. A duodenal resection with duodenojejunostomy was performed. Pathologic examination revealed a cavernous hemangiomatosis of the duodenum. The patient had a good postoperative course. Hemangioma of the intestinal tract is rare. To our knowledge, the present case is the first case in which urgent endoscopy has succeeded in establishing the preoperative diagnosis of this lesion and ascertaining the bleeding point.

Adult↗
PubMed1978

An increase of plasma triiodothyronine and thyroxine after administration of dexamethasone to hypothyroid patients with Hashimoto's thyroiditis.

In an attempt to study the effect of adrenal steroids on plasma thyroid hormone concentration in patients with Hashimoto's thyroiditis, 2 mg dexamethasone was administered for 2-4 weeks to 9 patients with normal plasma TSH, 3 patients with compensatory increase of plasma TSH, and 10 patients with a marked elevation of plasma TSH. Dexamethasone depressed plasma T4, T3, and TSH and reduced thyroid size in nine euthyroid patients, whereas a similar treatment did not affect plasma T3 and T4, but reduced plasma TSH and thyroid size in three patients with compensatory increase of plasma TSH. In contrast, dexamethasone elevated plasma T3 and T4 in 10 hypothyroid patients with a marked elevation of plasma TSH. The increase of T3 was more than that of T4, suggesting preferential secretion of T3. Plasma TSH was reduced, but was still above normal after administration of dexamethasone. It is suggested that the intrathyroidal autoimmune processes inhibiting thyroid hormone synthesis are significant in patients with more severe Hashimoto's thyroiditis, and that dexamethasone stimulated hormone synthesis by depressing the autoimmune processes.

Adolescent↗
PubMed1978

Age-related glucose intolerance in hyperthyroid patients.

In an attempt to study age-related metabolic abnormalities, glucose intolerance and serum insulin were examined in normal subjects and hyperthyroid patients. For comparison, serum concentrations of thyroxine (T4), triiodothyronine (T3), and total cholesterol were also measured in normal subjects and hyperthyroid patients. Although serum T4 concentration remained unchanged, serum T3 concentration decreased significantly in an elderly group of normal subjects. Similarly, serum T4 did not change with age and serum T3 decreased slightly but progressively with age in hyperthyroid patients. In addition, serum total cholesterol concentration increased progressively with age in normal subjects. Oral glucose tolerance decreased with age in normal subjects despite the same timing, peak level attained, and total magnitude of insulin response for old and young subjects. Although the severity of hyperthyroidism decreases with age, age-related glucose intolerance was much more apparent in hyperthyroid patients because of the age-related decrease of basal concentration, the peak level attained, and the total magnitude of insulin response. It is suggested that age-related glucose intolerance is magnified by the hyperthyroid state.

Adolescent↗
PubMed1976

Effects of excess iodide and other anions on thyroid hormone secretion in normal or hypophysectomized rats treated with graded doses of thyroid hormone.

In order to obtain further information about the stimulatory action of excess iodide on thyroid hormone secretion in thyroxine (T4)-treated rats, experiments were performed in hypophysectomized rats, or rats treated with graded doses of T4 or triiodothyronine (T3).T3 as well as T4 played a permissive role in the production of the iodide effect in normal animals, but T3 was more effective than T4. Excess iodide stimulated thyroid hormone secretion in hypophysectomized animals, this finding being compatible with the hypothesis that, by inhibiting TSH secretion, T3 and T4 produced a condition in which excess iodide stimulated thyroid hormone secretion in intact rats. However, T4 played an additional role in thyroid hormone secretion by acting directly on the thyroid. In hypophysectomized animals, small doses of T4 stimulated thyroid hormone secretion, and this action was additive to that of excess iodide, whereas large doses of T4 were inhibitory and reduced the effectiveness of excess iodide. The stimulatory action on thyroid hormone secretion was specific for iodide and was not shared by other anions. The action of excess iodide was blocked by methimazole. We suggest that excess iodide stimulates thyroid hormone secretion by increasing intrathyroidal concentrations of cyclic AMP in the absence of TSH, and that this increase in cyclic AMP concentration is blocked by methimazole.

Animals↗
PubMed1976

Volume of sella turcica in normal subjects and in patients with primary hypothyroidism and hyperthyroidism.

In an attempt to assess a possible relationship between pituitary size and TSH secretion, the volume of sella turcica was measured in 570 subjects, 26 primary hypothyroid patients, and 34 thyrotoxic patients. The volume of sella turcica, measured by a 3-dimensional approach, increased progressively with age until 20 years of age and was rather constant thereafter in normal subjects. In thyrotoxic patients, the volume of sella turcica was normal in spite of decreased plasma TSH concentration. In contrast, 81% of primary hypothyroid patients had an abnormal enlargement of the sella turcica. The magnitude of an increase of sella turcica inversely related with a decrease in serum T4 and T3 concentrations. On the other hand, the magnitude of an increase of sella turcica correlated well with an increase of circulating TSH. We suggest that an increase of sella turcica indirectly reflects an increase in pituitary size and TSH-secreting capacity, possibly due to hypertrophy and hyperplasia of TSH cells in primary hypothyroid patients.

Adolescent↗
PubMed1975

Pituitary unresponsiveness to thyrotropin-releasing hormone in thyrotoxic patients during chronic anti-thyroid drug therapy and in rats previously treated with excess thyroid hormone.

In an attempt to study pituitary-thyroid feedback control in thyrotoxic patients, TRH tests were performed in 10 thyrotoxic patients who were treated for varying intervals with propylthiouracil. Plasma TSH was undetectable before and after administration of 500 mug TRH in 7 patients (euthyroid or hypothyroid) after therapy for 1 to 4 months. Also, plasma TSH was undetectable before and after TRH in 3 patients who had been euthyroid for at least 6 months. To explore this abnormality, rats were made thyrotoxic by administering large doses of thyroxine or desiccated thyroid for 3 to 28 days. Discontinuation of thyroid hormone administration was followed by a significant but temporary fall of plasma thyroxine and triiodothyronine concentration below control levels. Duration of the low plasma thyroxine and triiodothyronine concentration was longer with the prolonged administration of thyroid hormone. Despite low plasma thyroxine and triiodothyronine concentrations, plasma TSH was below normal before and after administration of TRH. This unresponsiveness of the pituitary to TRH may be comparable to that found in thyrotoxic patients receiving antithyroid drugs for a certain period. Since this pituitary unresponsiveness to TRH in rats is due to a depletion of pituitary TSH content, it is suggested that depletion of pituitary TSH in thyrotoxic patients during antithyroid therapy is the cause of pituitary unresponsiveness to TRH.

Adult↗
PubMedDate not supplied

Retrospective study on the effects of lipiodolization before a potentially curative hepatectomy for colorectal liver metastases: long-term results of a pilot study.

BACKGROUND/AIMS: Lipiodolization, a selective regional cancer chemotherapeutic modality using lipiodol plus anticancer drugs, can prolong the survival time of patients with unresectable liver cancer. A preliminary study was conducted with adjuvant lipiodolization before a potentially curative hepatectomy for patients with metachronous colorectal liver metastases. The ultimate aim of this study was to improve the long-term survival after hepatectomy. METHODOLOGY: Twenty-one consecutive patients with colorectal hepatic metastases were included in this study. Seven patients underwent preoperative lipiodolization, while the remaining 14 patients did not receive any preoperative adjuvant therapy. The clinicopathological features and prognoses of these patients were investigated. The median follow-up period after a curative hepatectomy was 56 months. RESULTS: The clinicopathological factors did not differ markedly between the 2 groups. However, the cumulative survival rate of the 7 patients receiving preoperative lipiodolization was significantly (P < 0.05) better than that in those not receiving any preoperative treatment. CONCLUSIONS: Based on the above encouraging findings, we therefore propose that a prospective randomized trial should be carried out to confirm the beneficial effects of our adjuvant chemotherapeutic modality on patient survival following a curative hepatectomy for the patients with colorectal liver metastases.

Aged↗