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Biomedical subjects

I Kaneko

Publications and source records attributed to I Kaneko.

At least 55 records · Page 3Linked to original sources

Novel microbial metabolites of the phoslactomycins family induce production of colony-stimulating factors by bone marrow stromal cells. II. Isolation, physico-chemical properties and structure determination.

Leustroducsins (LSNs) A, B and C, novel inducers of colony-stimulating factors (CSFs), were isolated from culture broth of Streptomyces platensis SANK 60191 mainly by ethyl acetate extraction and preparative reverse-phase HPLC. The molecular weights and molecular formulae of LSNs A, B and C are 641: C32H52O10NP, 669: C34H56O10NP and 669: C34H56O10NP, respectively. The structure elucidation revealed that they belong to the phoslactomycin group antibiotics, and their structures contain an alpha,beta-unsaturated delta-lactone, an amino group, a phosphate ester and a cyclohexane ring moiety. The structures differ only at the substituent bound to the cyclohexane ring.

Bone Marrow↗

[The estimation of daily physical activity with the coefficient of variation (CV) of heart rates continuously recorded].

The daily level of physical activity was estimated using the heart rate monitor, PE3000 (Polar Electro, Finland). The level was expressed with the coefficient of variation (CV) of heart rates recorded from waking time to dinner time. In the course of a day of intense physical activity, CV was confirmed to rise significantly. Then the CV was estimated and compared among 3 age classes, young (10-18 years), middle-aged (30-47 years), and elderly (62-76 years). The CVs of young people were significantly higher than those of middle-aged (P < 0.001) and elderly (P < 0.01), regardless of sex. However there was no significant sex difference in all age classes. These results suggest that the CV is an accurate index of daily physical activity. Thus clinicians can use the CV of heart rates to estimate the level of physical activity of individuals which closely relates to QOL.

Activities of Daily Living↗

[A cinefluorographic study of hyoid bone movement during deglutition].

A quantitative study was performed to analyze movement of the hyoid bone on swallowing in 71 patients with pharyngo-laryngeal neurosis (44 males, 27 females), who had no abnormal findings either morphologically or functionally. The lateral X-ray cine (30 frames/sec) was taken while the patients swallowed the contrast medium in the upright position, and precise movement of the hyoid bone was examined using a motion analyzer. The movement was divided into 5 phases; initial slow elevation from the resting position (1st elevation phase), then a quick upwards shift to the highest position (2nd elevation phase), where the hyoid bone remained temporarily (static phase), followed by rapid and slow descending shifts towards the resting position (1st and 2nd descending phase, respectively). The resting position of the hyoid bone is significantly lower in males than in females and it seemed to get lower with age in both sex. When compared to the younger group (age 10-30), the older group (age 60-70) had significantly more distance and longer duration of deglutition in the 1st elevation phase, whereas the 2nd elevation phase did not differ among the age group. The results of this study indicate that prolongation of the time and distance of the 1st elevation phase are more significant in the older group, which may well explain the cause of delayed of deglutition.

Adolescent↗

[A new principle and device for radiosurgery using a linear accelerator; its principle, devices and clinical trials].

The authors have developed new devices for stereotactic radiosurgery using a conventional linear accelerator (LINAC). The system of devices consists of a rotatory chair with a base ring holder, a Brown Robert Well's stereotactic apparatus (BRW's apparatus) with a double set of base rings and a number of precise collimators which eliminate penumbra to the greatest extent. A study rotatory chair was manufactured, whose vertical axis of rotation is always set and stable. A strongly built, adjustable holder for the BRW's base ring is attached to the chair. The principle and flow of procedures step by step is as follows; 1). The rotatory chair is carried in under the linear accelerator and the vertical rotatory axis of the chair is precisely adjusted to align with the vertical center of the photon beam from the LINAC. 2) A base ring and a locator of BRW's apparatus are mounted on a patient's head and three coordinates of a target are determined by CT scans. 3) The target indicator of the dummy set of BRW's apparatus is positioned according to X, Y, Z coordinates of the target. The tip of a rod indicator fixed on an instrument bloc on the arc device is precisely adjusted to touch at the tip of the target indicator. 4) The base ring and arc device with rod indicator are transferred together from the BRW's dummy set to the rotatory chair and fixed to the base ring holder. The tip of the rod indicator is precisely adjusted to be positioned at the isocenter of the LINAC. 5) The base ring and arc device are removed and replaced by another base ring mounted on the head of a patient, who is made to sit on the rotatory chair. The target in the brain is now located at the isocenter of the LINAC. Stereotactic radiation is started with rotation of the chair and circular movement of the gantry of the LINAC. The chair is rotated at a speed of 100 degrees per second, and the gantry of the LINAC is moved slowly on a circular trajectory from +115 degrees to -115 degrees. Fourteen cases, including AVM, cavernous angioma, acoustic tumor and glioma have been treated so far. Three cases of large AVM were treated by a combination of artificial embolization and stereotactic radiosurgery.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

Inhibition of human immunodeficiency virus type-1-induced syncytium formation and cytopathicity by complestatin.

Complestatin, an anti-complement agent, was shown to be a potent inhibitor of human immunodeficiency virus type 1 (HIV-1) infection in vitro. It inhibited HIV-1-induced cytopathicity and HIV-1 antigen expression in MT-4 cells; the 50% effective doses for these effects were 2.2 and 1.5 micrograms/ml, respectively. No toxicity for MT-4 cells was observed at concentrations up to 400 micrograms/ml. In addition, the agent inhibited the focus formation in HT4-6C cells (CD4-positive HeLa cells); the concentration for 50% focus reduction was 0.9 microgram/ml. HIV-1-induced cell fusion in cocultures of MOLT-4 cells and MOLT-4/HTLV-IIIB were also blocked by complestatin (the concentration for 50% cell fusion inhibition, 0.9 microgram/ml). Complestatin had no ability to inhibit HIV-1 reverse transcriptase activity. When MT-4 cells were pretreated with complestatin for 2 hrs prior to the exposure to HIV-1, the HIV-1-induced cytopathicity was markedly inhibited, while pretreatment of HIV-1 with the agent did not affect the infection. These results suggest that complestatin primarily interacts with cells and inhibits viral adsorption to the cell surface as well as adsorption of infected cells to adjacent cells.

Amino Acids↗

Metalloproteinases in the mineralized compartments of porcine dentine as detected by substrate-gel electrophoresis.

Several gelatinolytic activities were detected in the 4M guanidine HCl-soluble fraction extracted from demineralized porcine dentine matrix. These matrix proteinases were active in the range of pH 6-9, and the activities were enhanced by calcium ions. The enzymes also degraded some of the non-collagenous proteins coexisting in the extract. The results indicate that the changes in the composition of non-collagenous proteins during the development of dentine are related to proteolytic enzyme activity.

Albumins↗

Reparability of DNA double-strand breaks and radiation sensitivity in five mammalian cell lines.

We examined the relationship between gamma-ray-induced DNA double-strand breaks (dsb) and cell lethality in five mammalian cell lines differing in radiosensitivity; HA-1, HMV-I, L5178Y, M10 and LX830. These cells were derived from Chinese hamster, human melanoma, and mouse lymphoma (parent and its radiosensitive mutants), respectively. HA-1 cells were the most radioresistant and LX830 cells were the most radiosensitive among these five lines. Although the induction of dsb by gamma-rays for HA-1 was significantly different from other curves (p less than 0.05 for HMV-I and p less than 0.01 for L5178Y and M10), those for the other four lines were similar to one another. In addition, the most radioresistant cell line, HA-1, showed the highest dsb induction among five cell lines. Therefore, there is no correlation between radiosensitivity and the induction of dsb in these five lines. On the other hand, residual dsb after repair incubation (non-reparable dsb) do differ from each other. When the relative number of non-reparable dsb was plotted against the radiation dose, the dose-response curves for all the cell lines were concave, and the slopes of curves for M10 and LX830 were steeper than those for other cell lines. These curves are a mirror-image of the survival curves. The results suggest that there is a correlation between the radio-resistance in terms of cell killing and the capacity of cells to repair dsb.

Animals↗

Combined cisplatin and radiation therapy for advanced bladder cancer.

Since September 1985, 44 patients with advanced urinary bladder cancer have been treated by combined cisplatin and full-dose radiotherapy. The patients were 32 males and 12 females, and their ages ranged from 33 to 83 years, with a median of 67.4 years. Radiotherapy consisting of a tumor dose of 50-60 Gy was administered with cobalt-60. Cisplatin was infused 5 days at a daily dose of 20 mg on the 1st and 4th weeks of treatment. Of the 39 evaluable patients 27 (69.2%) achieved a complete response. Toxicity was also evaluated for those 44 patients. Mainly gastrointestinal toxicity was noted: loss of appetite in 28 (64%), nausea and/or vomiting in 21 (48%), and diarrhea in 8 (18%). Leukocytopenia was noted in 16 (33%) and mild thrombocytopenia in 5 (11%). Mild dermatitis was noted in 8 (18%).

Aged↗

Effect of alpha-chloralose on disposition and pharmacological action of orally administered chlorzoxazone in rats.

The pharmacodynamic behavior of orally administered chlorzoxazone (CZX) was studied in rats. From the time course of CZX plasma concentration data under alpha-chloralose (80 mg/kg, i.p.) anesthesia, it was found that CZX obeyed a one-compartment model with first-order absorption. The pharmacological response intensity of CZX on the crossed extensor reflex was closely related to the plasma concentration data via Hill's equation under alpha-chloralose (80 mg/kg) anesthesia, but not at a 150 mg/kg dose. The influence of alpha-chloralose at the latter dose on CZX pharmacokinetics and pharmacodynamics appeared to be due to the pharmacodynamic interaction of alpha-chloralose and CZX, thus suggesting that the pharmacokinetic and pharmacodynamic concept proposed by Smolen was not applicable to CZX's behavior at such a dose in rats. Under alpha-chloralose (80 mg/kg) anesthesia, the biophase compartment was determined to be identical to the central compartment using our proposed model. On the basis of the effect of anesthetics on drug behavior, one may select an appropriate anesthetic dose to evaluate the relationship between the plasma levels and the onset and duration of the drug action. At the higher dose of alpha-chloralose (150 mg/kg), the free fraction of CZX was increased and a possible enhancement in CZX action was suggested.

Administration, Oral↗

[2,450MHz hyperthermia for malignant stenosis of the bile duct--development of a new biliary drainage tube united with a thermocouple].

We have developed new biliary drainage tubes (10 Fr and 12 Fr size) united with a thermocouple, through which we could apply 2,450MHz hyperthermia more exactly monitoring the tissue temperature in 3 cases with biliary obstruction than intracatheter hyperthermia methods already reported. One patient was discharged asymptomatic without jaundice after the removal of the drainage tube.

Aged↗

Correlation between non-repairable DNA lesions and fixation of cell damage by hypertonic solutions in Chinese hamster cells.

In Chinese hamster HA-1 cells, killing induced by gamma-rays was enhanced by post-irradiation treatment with hypertonic solution (0.5 mol/l NaCl in phosphate buffered saline, pH 7.2) for 20 min. The initial DNA double-strand breaks (dsb) induced by gamma-rays were repaired during post-irradiation treatment with hypertonic solution. However, hypertonic treatment following gamma-irradiation enhanced the frequency of non-repairable dsb, as compared with the frequency after incubation at 37 degrees C following gamma-irradiation. Hypertonic treatment did not affect the initial half-time for rejoining of dsb. Hypertonic treatment did not enhance cell killing, nor did it enhance the non-repairable dsb when the irradiated cells were incubated at 37 degrees C for 2 h. These results suggest that fixation of gamma-ray-induced potentially lethal damage by hypertonic treatment results from inhibition of the rejoining of dsb.

Animals↗

Time-lapse microscopy and DNA double-strand breakage of Chinese hamster cells under conditions promoting or preventing PLD repair after irradiation with 60Co gamma rays.

We have confirmed previous time-lapse microscopic observations (Suzuki 1985) using Chinese hamster hai and V79 cells. The proportion of non-dividing to dividing cells was the same under conditions of potentially lethal damage (PLD) repair and non-PLD repair after irradiation with 60Co gamma-rays. This finding suggested that the radiation-induced damage to cellular DNA was similarly repaired so that cells undergo a first division to the same extent under both sets of conditions. In fact, direct measurement of double-strand breaks (dsb) in DNA from the two cell lines by the neutral elution technique showed no differences either in the initial amount of damage or in the time-course under conditions promoting or preventing PLD repair. These results indicate that PLD repair (i.e. an increase in cell survival) cannot be simply explained by a difference in the repair of dsb, but it can perhaps be explained by assuming that DNA damage is repaired with either fewer or more errors in the presence or absence of PLD repair respectively.

Animals↗

Analysis of chromatid damage in G2 phase induced by heavy ions and X-rays.

The induction of chromatid aberrations was examined in Golden hamster embryo (GHE) cells 2 h after exposure to X-rays or heavy ions. Compared with X-rays the frequencies of gaps and deletions were almost one-half in the case of He ions, and much lower in cells irradiated with N ions. The induction of exchanges by He ions and N ions was also less than that by X-rays. The relative number of gaps, deletions and exchanges were 0.4, 0.5 and 0.4 for He ions, and 0.2, 0.2 and 0.4 for N ions. The mitotic indices were almost the same in X-irradiated and heavy-ion-exposed cells. Chromatid aberrations induced by heavy ions tended to persist longer than those induced by X-rays during successive culture passages after exposure. The present results suggest a difference in the quality of chromatid damage induced by X-rays and heavy ions.

Animals↗

Relation of disposition kinetics to pharmacological effect of intravenous administration of chlorzoxazone in rats.

The quantitative relationship between a drug disposition and the pharmacological effect was examined in rats using chlorzoxazone (CZX), a centrally acting muscle relaxant, as a model drug. After intravenous administration of CZX, the decay of the plasma concentration was rapid and it was found that CZX obeyed one compartment open model in the dose range of 5 to 25 mg/kg studied. The pharmacological response intensity was determined by means of the crossed extensor reflex. The duration of the muscle relaxant effect was proportional to the logarithm of the dose of CZX. The time course of the calculated plasma concentration was well related to the pharmacological response intensity via a Hill's equation and the simulated pharmacological response intensity which was obtained by means of the equation was coincident to the time course of the response data. These results indicated that the time course of pharmacological response intensity was able to be predicted using the time course of plasma concentrations. From the analysis of the quantitative relationship between the concentration and the effect under the present experimental conditions studied, it was found that the biophase compartment was identical to the central compartment as long as the first order processes were proceeding. These findings implied that the time course of pharmacological response would be quantitatively predictable from the disposition kinetics of CZX after the intravenous administration.

Animals↗

[Clinical feature of odontogenic maxillary sinusitis--symptomatology and the grade in development of the maxillary sinus in cases of dental maxillary sinusitis].

Odontogenic maxillary sinusitis may occur by draining of an apical dental root abscess into the maxillary sinus. It has been reported that the disease is usually frequent in cases aged of the second and third decades. In most of them, either the first or second molar tooth is assumed to be the origin of the disease. As clinical characteristic symptoms, it is mentioned that an acute unilateral sinusitis appears since the onset and the patient complains a fetid purulent nasal discharge from an early stage. The symptom and its clinical time course in 43 cases with dental maxillary sinusitis, who had been treated by surgical procedures in ENT Clinic in Kitasato University Hospital during past 14 years from 1972 to 1985, were studied retrospectively. The size of the affected maxillary sinus in each case of the disease was measured from the X-ray films. An influence of development of the maxillary sinus to the occurrence of dental sinusitis was discussed by comparing the sizes of the maxillary sinuses in both the group of the disease and the group of simple unilateral maxillary sinusitis.

Adolescent↗

[Treatment using CDDP and radiation therapy in treating bladder tumor].

Combination therapy consisting of cis-diamine-dichloroplatinum (CDDP) and radiotherapy was used to treat bladder cancer. The subjects were 20 patients with bladder cancer we experienced since September, 1986. They were between 33 and 83 years old and consisted of 13 males and 7 females. Among the histotypes and grades, there were 3 cases of G2, 7 of G2-G3 and 10 of G3 metastatic epithelial carcinoma. The classification of primary tumors was T2 in six cases, T3a in 12 cases and T4 in two cases. In 12 cases where the bladder was preserved, this therapy was performed after TUR biopsy or TUR, and the effects were evaluated after observation periods of 5-17 months. Side effects caused by CDDP were anorexia in 15 cases, nausea and vomiting in 10 cases, leukopenia in 10 cases and thrombocytopenia in four cases. Those caused by the radiotherapy were diarrhea in seven cases and skin disorders in six cases. All of these side effects were mild and the patients recovered spontaneously.

Adult↗

Stabilizing effects of some amino acids on membranes of rabbit erythrocytes perturbed by chlorpromazine.

Hemolysis experiments indicated that glycine (20 mM) remarkably suppressed the chlorpromazine (CPZ)-induced osmotic permeability enhancing effect in rabbit erythrocytes. Lysine and aspartic acid also showed a similar protecting effect at the same concentration. Thus, the acid-base properties of amino acids were not a determining factor in stabilizing the cell membranes perturbed by CPZ. These results suggest that amino acids stabilize the membranes of the erythrocytes by inhibiting the osmotic water transfer from the outside to the inside of the cells. The kinetic studies in isotonic suspensions of erythrocytes indicated that glycine decreased the hemolytic activity of CPZ, and it was suggested that glycine molecules possibly inhibited penetration of CPZ into the cell membranes. The data also showed that the membrane stabilizing action of glycine was not affected by the dissociation of CPZ molecules. The degree of dissociation of glycine molecules was not found to be related to the degree of the protection. The FT-IR spectroscopy data indicated that glycine made the acyl chains of the liposome perturbed by CPZ more orderly.

Amino Acids↗