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Biomedical subjects

T Hidaka

Publications and source records attributed to T Hidaka.

At least 127 records · Page 7Linked to original sources

Anguinomycins C and D, new antitumor antibiotics with selective cytotoxicity against transformed cells.

The retinoblastoma protein (pRB) is inactivated during the development of a wide variety of human cancers. In the course of our screening for antitumor antibiotics by using pRB-inactivated cells, an actinomycete strain was found to produce two active substances, which were elucidated to be new members of the leptomycin-anguinomycin family by NMR spectral analysis and were designated anguinomycins C and D. The anguinomycins induced growth arrest against normal cells and induced cell death against transformed cells, in which pRB was inactivated by viral oncoproteins such as human papillomavirus E7, adenovirus E1A and simian virus 40 large T antigen.

Animals↗

[Two surgical cases of tectal glioma].

Tectal glioma is rare and difficult to diagnose, and the tumor has been known as the tumor that gives no indication of the need for direct surgery because of its anatomical location. At present, MR imaging is available to detect the tumor and its location. We present two patients who underwent direct surgery. Case 1: A 18-year-old female was admitted with headache and nausea. MRI showed signs of stenosis of the aqueduct and a tumor of the tectal region. The tumor was removed partially. Histological examination of this tumor demonstrated a low grade astrocytoma. After surgery, hydrocephalus improved. Case 2: A 12-year-old boy was admitted with hydrocephalus detected by CT. MRI demonstrated a tumor of the midbrain without confirmation. He underwent a V-P shunt for hydrocephalus, and was discharged without any complaints. After 2 years, he was admitted again with shunt malfunction. After shunt revision, his consciousness recovered. However, Parinaud's sign appeared and patency of the shunt was unstable. MRI revealed a tumor of the tectal region and signs of stenosis of the aqueduct of Sylvius. The tumor was removed directly by the occipital transtentorial approach. The aqueduct was opened and a catheter was inserted from the 3rd to the 4th ventricle. Histological examination revealed a low grade astrocytoma. The patient followed a satisfactory postoperative course except for slight Parinaud's sign, and the V-P shunt was no longer necessary.

Adolescent↗

[The efficacy of midazolam-famotidine suppository for premedication in children].

We evaluated the efficacy of midazolam-famotidine suppository (M-F suppository) for premedication in children. After obtaining informed parental consent, we studied children aged 5m-7y, ASA I status, scheduled for minor elective surgery. The suppository group (n = 26) was given suppository of both midazolam 0.5 mg.kg-1 and famotidine 2 mg.kg-1, and the intramuscular injection group (n = 19) was given hydroxyzine 1 mg.kg-1. In the suppository group, gastric pH (3.90 +/- 0.34) was significantly higher, and gastric volume (1.88 +/- 0.54 ml) was significantly less than in the intramuscular injection group (1.82 +/- 0.15, 8.42 +/- 1.76 ml). The M-F suppository may offer similar sedative effect as an intramuscular injection of hydroxyzine. We concluded that the M-F suppository is an effective premedicant for pediatric patients.

Administration, Rectal↗

[Renal ablation by transcatheter renal arterial embolization in the treatment of benign renal disease].

Renal ablation by transcatheter renal arterial embolization (TAE) was performed in 10 patients with benign renal disease (hydronephrosis n = 6; renovascular hypertension n = 3; nephrotic syndrome n = 1). Each affected kidney had little or no renal function. Six patients with hydronephrosis were treated with TAE using absolute ethanol alone in three patients and the combination of absolute ethanol and gelatin sponge in the other three. Each patient was followed by sclerotherapy of the pelvocalyceal system via nephrostomy using absolute ethanol. In four of the six patients, the embolized kidney had no urine, and there was very little urine in the remaining two. The size of the embolized kidney was markedly decreased on CT. The three patients with renovascular hypertension were pre-studied by selective and renal vein sampling for PRA, and the kidney excreting higher renin was embolized by TAE with absolute ethanol. Blood pressure has become manageable without antihypertensive drug in two patients and with a reduced amount of drug in one. The patient with nephrotic syndrome had end stage renal failure and showed significant protein excretion. To prevent further protein loss, both kidneys were embolized with stainless steel coils. Urine output was significantly decreased, and consequently, hypoalbuminemia improved. All patients tolerated the procedure well, and there were no significant complications. Renal ablation by TAE may be an alternative to surgical treatment in selected patients with benign renal disease, particularly in patients with contraindications to surgery and in the elderly. Absolute ethanol and gelatin sponge seem safe and effective for TAE in patients with hydronephrosis and renovascular hypertension. For hydronephrosis, we recommend combining TAE with sclerotherapy of the pelvocalyceal system via nephrostomy using absolute ethanol. Though we successfully applied steel coil for the patient with nephrotic syndrome, absolute ethanol may be equally effective.

Adult↗

DP-1904, a specific inhibitor of thromboxane A2 synthesizing enzyme, suppresses ICAM-1 expression by stimulated vascular endothelial cells.

Intercellular adhesion molecule-1 (ICAM-1) is an antigen that is strongly expressed by vascular endothelial cells at sites of local inflammation and participates in the development of inflammation. In the present study, vascular endothelial cells were stimulated by inflammatory cytokines that promote thromboxane A2 synthesis to observe their effects on the expression and shedding of ICAM-1 on the cell surface. In addition, the suppressive effects of DP-1904 ([+/-]-6-[1-imidazolylmethyl]-5,6,7,8-tetrahydronaphthalene-2- carboxylic acid hydrochloride hemihydrate), a thromboxane A2 synthesis inhibitor, on ICAM-1 expression were evaluated. ICAM-1 expression on the surface of human umbilical vein endothelial cells was increased significantly by stimulation with interleukin-1 beta, tumor necrosis factor alpha (TNF alpha), thrombin and platelet-activating factor (PAF). DP-1904, an inhibitor of thromboxane A2 synthesis, significantly suppressed the expression of ICAM-1 on the surface of human vascular endothelial cells that had been stimulated by TNF alpha or PAF. These findings suggest that an enhanced expression of thromboxane A2 on human vascular endothelial cells is closely related to the expression of ICAM-1 on the surface of these cells.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗

High-performance liquid chromatographic determination of 3'-hydroxy-5'-(4-isobutyl-1-piperazinyl)benzoxazinorifamycin (KRM-1648) and its deacetyl metabolite in plasma, whole blood, urine and tissue samples in rats.

A reversed-phase high-performance liquid chromatographic method was developed for the determination of 3'-hydroxy-5'-(4-isobutyl-1-piperazinyl)benzoxazinorifamycin (KRM-1648, I), a new rifamycin derivative, and its 25-deacetyl metabolite (KRM-1671, II) in plasma, whole blood, tissues and urine from rats. I and II were coextracted with an internal standard from each sample matrix by solid-phase extraction (Bond Elut). Plasma and urine were directly loaded onto Bond Elut, while whole blood and tissues were homogenized and extracted with methanol or dichloromethane-chloroform prior to Bond Elut extraction. The extracts were chromatographed on Shim-pack CLC-ODS(M) using acetonitrile-0.02 M citrate buffer containing 0.1 M sodium perchlorate (2:1, v/v), and peaks were detected at 643 nm. The validation data showed that the assays for I and II in plasma, whole blood, tissues and urine were selective, accurate and reproducible.

Animals↗

Pineal yolk sac tumor in a 65-year-old man.

A 65-year-old man presented with a case of pure yolk sac tumor in the pineal region. The patient was admitted with a gait disturbance and elevated alpha-fetoprotein levels in serum and cerebrospinal fluid. He underwent total resection of the tumor. Cisplatin-vinblastine-bleomycin therapy was interrupted because of severe syndrome of inappropriate secretion of antidiuretic hormone, and there was recurrence of the tumor. Five months after the operation, he died in spite of carboplatin-etoposide therapy. A review of the literature revealed no previous report of pineal yolk sac tumor in an elderly patient. Problems in the diagnosis and treatment of such cases are discussed.

Aged↗

Acylated flavonoids in callus cultures of Citrus aurantifolia.

Two new acylated flavonol glycosides were isolated along with kaempferol 3-O-beta-rutinoside from 10-year-old callus cultures of Mexican lime. The structures of these new compounds are kaempferol 3-O-beta-D-glucopyranoside-6"-(3-hydroxy-3-methyl glutarate) and kaempferol 3-O-beta-D-glucopyranoside-6"-(3-hydroxy-3-methyl glutarate)-7-O-beta-D-glucopyranoside.

Cell Line↗

Increased endothelin-1 production in fibroblasts derived from patients with systemic sclerosis.

OBJECTIVES: To determine whether fibroblasts from patients with systemic sclerosis (SSc) produce excessive amounts of endothelin-1 (ET-1), which is recognised as having vasoconstrictive properties and as having a potent mitogenic effect on fibroblasts. METHODS: Dermal fibroblasts were removed from 11 patients with SSc and from five normal controls (NC). The assay of ET-1 protein was measured by an ELISA that used two anti-ET-1 antibodies. The gene expression of prepro ET-1 mRNA was evaluated by a reverse-transcriptase polymerase chain reaction (RT-PCR) method. RESULTS: Levels of ET-1 protein were significantly higher in SSc fibroblast cultures than in those of normal fibroblasts (p < 0.01). The expression of prepro ET-1 mRNA was also higher in SSc fibroblasts than in normal fibroblasts. The addition of interleukin-1 beta (IL-1 beta) increased the production of ET-1 by fibroblasts. CONCLUSION: The findings indicate that the overproduction of ET-1 is a novel abnormal function in SSc fibroblasts, and that ET-1 induced by fibroblasts may play a role in the fibrosis and Raynaud's phenomenon of SSc.

Adult↗

Amyloidosis secondary to rheumatoid arthritis associated with plexiform change in bilateral temporal lobes.

A 70-year-old woman with rheumatoid arthritis (RA) and secondary amyloidosis presented repeated consciousness loss. The pathological findings at autopsy revealed multi-organic deposits of amyloid A-protein and so-called 'plexiform change' of blood vessels in bilateral temporal lobes. The arterial plexiform change, which is found in the lung specimen of primary pulmonary hypertension, might be a new pathological cerebrovascular change associated with RA.

Aged↗

[A case of malignant fibrous histiocytoma in the mediastinum].

A 81-year-old man was admitted to the hospital because he complained of hoarseness. Chest radiography showed a mass in the right upper mediastinum. An operation was done to remove the mass and make a conclusive diagnosis. Histologically, the tumor tissue consisted of spindle-shaped fibroblast-like cells and round histiocyte-like cells with bizarre giant cells. Part of the tissue had a storiform pattern. These findings led a diagnosis of malignant fibrous histiocytoma (MFH) of the "usual type". MFH is known to occur frequently in the soft tissues of extremities, trunk, and retroperitoneum, but it is seldom detected in the mediastinum. We report here a rare case of primary MFH in the mediastinum.

Aged↗

[Orbito-cranial reconstruction and unilateral optic canal release in a patient with left fronto-orbital fibrous dysplasia: a case report].

A surgical case of monostotic fibrous dysplasia of the left frontal and sphenoidal bone in a 14-year-old girl is described. This girl was admitted to our hospital in March, 1992, with a chief complaint of facial deformity and asymmetry due to a painless and progressive bony bulging over the left fronto-orbital region. But she denied any symptoms such as proptosis, diplopia, optic atrophy and visual loss. Other data found on neurological examination and laboratory tests were normal. In addition, she had no history of skin lesions, precocious puberty or other endocrine abnormalities. Plain craniogram showed remarkable thickening of the left frontal bone and of the anterior cranial fossa of the sphenoidal bone with irregular stenosis of the left optic canal. CT scan showed the diffuse enlargement of the affected bone and involvement of the paranasal sinuses. Angiography revealed no positive findings. On December 10, 1992, orbito-cranial reconstruction and unilateral optic canal release were performed using an extradural approach through a left fronto-temporal craniectomy. Histological findings confirmed the lesion to be typical fibrous dysplasia. She recovered completely one month after the operation, but she suffered transient blurred vision, diplopia and left ptosis. Most of the decreased vision caused by fibrous dysplasia cannot be reversed after surgical treatment. So, if optic canal stenosis is evident, even when visual loss is not clear, release of the optic canal stenosis should be done as early as possible in association with experienced neurosurgeons and with meticulous dissection.

Adolescent↗

[Therapeutic efficacy of a benzoxazinorifamycin, KRM-1648, in Mycobacterium intracellulare infection induced in mice].

Therapeutic efficacy of KRM-1648 was studied in BALB/c mice infected with Mycobacterium intracellulare. Mice were infected intravenously with 1.0 x 10(7) CFU of the organisms/mouse and then given 0.2 mg or 0.4 mg of KRM-1648 emulsified in 2.5% gum arabic-0.2% Tween 80 by gavage, once daily, 6 days per week, from day 1 to the death of mice. The therapeutic efficacy of the drug was evaluated on the basis of survival times, incidence and degree of gross lung lesions and bacterial loads in the lungs and spleen. The lung lesions were not observed in any experimental groups at 4 weeks after the infection. At 8 weeks after the infection, the lung lesions were observed in all control mice, but 2 of 5 mice treated with 0.2 mg of KRM and 4 of 5 mice treated with 0.4 mg of KRM did not show any lung lesions, and the degree of the lesions was much milder in KRM-1648-treated mice than in the control mice. All mice of treated and untreated groups died, and median survival times were 141 days for the control mice, 216 days for mice treated with 0.2 mg of KRM-1648 and 220 days for mice treated with 0.4 mg of KRM-1648. At the death, lung lesions were observed in all mice. The CFUs of M. intracellulare in the lungs and spleen in mice treated with KRM-1648 were fewer than those in the control mice at 4 and 8 weeks after the infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

[Clinical evaluation of diazepam suppository for premedication in children].

Anesthesiologists need a safe and effective premedication before general anesthesia and want to help decrease anxiety and minimize psychologic trauma to children. Therefore, we evaluated diazepam suppository (0.5 mg.kg-1 body weight) administered to 21 children before minor surgery under general anesthesia. We evaluated the sedative effect of the diazepam suppository (tablet) on the arrival at the operating room, during anesthesia induction and in the recovery room. On the arrival at operating room, 86% of children were sedated, and 65% of children could be induced smoothly under mask. There was no delayed emergence. Plasma diazepam level at induction was 376.5 +/- 28.4 ng.ml-1, which is the level needed for sedation. We conclude that diazepam suppository is a useful drug for premedication in children.

Anesthesia, General↗