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Biomedical subjects

H Iida

Publications and source records attributed to H Iida.

At least 487 records · Page 27Linked to original sources
PubMed1986

Heat shock induction of intranuclear actin rods in cultured mammalian cells.

Incubation of cultured cells of mouse C3H-2K fibroblastic cell line and other mammalian cell lines at 42.0-43.0 degrees C for 30 min or longer caused disintegration of normal actin structures including stress fibers, and induced formation of intranuclear actin paracrystal-like structures, called actin rods. When cells exposed to the elevated temperatures were shifted back to 37 degrees C, normal actin structures were regained. Pretreatment of cells at moderately high temperatures such as 38.5 degrees C inhibited formation of the actin rods upon subsequent exposure to 42.0 degrees C. Neither microtubules nor intermediate filaments were disrupted by the heat treatment. Several heat shock proteins were found to be synthesized under the conditions where actin rods were induced. However, there is no causal relationship between two cellular events, the induction of intranuclear actin rods and the synthesis of heat shock proteins.

Actins↗
PubMed1986

Inhibition of the formation of 13,14-dihydroprostaglandin F2-alpha induced by chlorpromazine in rat ovary.

The present study was designed to investigate the effects of chlorpromazine (CPZ) on the formation of 13,14H2-PGF2 alpha in rat ovary and the possibility that the "critical period" observed in the effect of CPZ for the blockade of ovulatin may be appreciated by measuring the formation of 13,14H2-PGF2 alpha as a parametor. When CPZ (4.0 mg/kg) was given s.c. at 10:00 a.m. once a day for 3 days from the first day of diestrus to the expected day of proestrus followed by sacrifice after 24 hours of the final injection, a significant inhibition was recognized in the formation of 13,14H2-PGF2 alpha in ovary. The effects of a single injection of CPZ were also determined 24 hours after injection at 10:00 a.m. on the day of diestrus I, diestrus II or proestrus. The results showed that the drug treatment on the day of proestrus significantly decreased the formation of 13,14H2-PGF2 alpha, but not on the day of diestrus I or II. When the formation of ovarian 13,14H2-PGF2 alpha was inhibited by CPZ treatment, the blockade of ovulation was also confirmed. A single injection of CPZ at 05:00 and 07:00 after the "critical period" on the day of proestrus did not inhibit the 13,14H2-PGF2 alpha formation in the rat ovary. It is concluded that the administration of CPZ before the "critical period" on the day of proestrus is effective in suppressing the ovarian 13,14H2-PGF2 alpha formation as well as on the blockade of ovulation.

Animals↗
PubMed1986

CAP therapy for advanced, recurrent and/or metastatic malignant tumors of the head and neck.

One-day CAP therapy utilizing CPM, THP-ADM and CDDP was performed on 33 patients with malignant tumors in the head and neck region which were able to be evaluated. As a result, CR was obtained in 6 patients and PR in 11 patients; thus the overall response rate was 51.5%. The present therapy is worthwhile as a neo-adjuvant chemotherapy and it was effective in patients with relatively severe systemic condition or those with lung metastasis. When the tissues were classified histologically, the present therapy was effective against anaplastic carcinoma and adenocarcinoma. Since agents significantly effective against adenocarcinoma have not been available so far, the present therapy is considered to be a useful method especially for the treatment of adenocarcinoma. Moreover, because irreversible side effects scarcely appeared and because the period for 1 course of treatment is short enough, the present therapy is considered to be a method with little burden on patients.

Adenocarcinoma↗
PubMed1986

Combination chemotherapy with CDDP and 5-FU in head and neck cancer.

Combination chemotherapy with CDDP and 5-FU was performed in 19 patients with evaluable head and neck cancer and 2 CR patients and 7 PR patients were obtained; thus the response rate was 47.4%. Histologically, the present therapy is considered to be especially effective against well differentiated squamous cell carcinoma (83.3%). The present therapy is considered to be useful as a neo-adjuvant chemotherapy (75.0%), but it is desirable to perform at least 2 courses of treatment. The side effects observed were nausea, vomiting, anemia, leukocytopenia and alopecia, etc., and most of them were reversible. However, there were 2 patients in which the continuation of chemotherapy was impossible due to renal disorders.

Adenocarcinoma↗
PubMed1986

T-lymphocyte subsets in patients with squamous cell carcinoma of the head and neck.

T-lymphocyte subsets in the peripheral blood of patients previously untreated for squamous cell carcinoma of the head and neck were investigated using monoclonal antibodies under flow cytometry before starting treatment. T-lymphocyte subsets in the peripheral blood of patients with squamous cell carcinoma did not significantly differ from those in the peripheral blood of healthy subjects, patients with benign tumors of the head and neck, patients with chronic sinusitis and patients with benign otolaryngological diseases. The necessity to investigate the function of T-lymphocyte subsets was suggested. It was furthermore suggested that T-lymphocyte subsets in cancerous tissues should be investigated.

Adult↗
PubMed1986

Error analysis of a quantitative cerebral blood flow measurement using H2(15)O autoradiography and positron emission tomography, with respect to the dispersion of the input function.

The effect of the inaccuracy of the input function on CBF measured by the H2(15)O autoradiographic method was investigated. In H2(15)O autoradiography the measured input function usually includes a larger dispersion than the true input function, as well as the absolute time axis having been already lost. The time constant of the external dispersion that occurred in our continuous sampling system was evaluated as 10-12 s when the dispersion function was approximated by a monoexponential function. The internal dispersion occurring in arterial lines in a human body was evaluated as 4-6 s. Such dispersion, indispensable in a patient study, was found to produce large errors in calculating CBF, e.g., 5(10) s of the dispersion caused +15(33) and +10(20)% systematic overestimations for the 40- and 60-s accumulation time respectively. An analytical correction employing an inverse Laplace transform was applied to clinical CBF studies, and the results were compared with those from the C15O2 steady-state inhalation method. Correction by 10 s in time constant, corresponding to the external dispersion, reduced the overestimation significantly from 70-100% to approximately 20%. Further correction by 5 s, corresponding to the internal dispersion, resulted in a negligible difference (less than a few percent) from the steady-state method.

Autoradiography↗
PubMed1986

Studies on 3-methoxy-4-hydroxyphenylglycol (MHPG) and 3,4-dihydroxyphenylglycol (DHPG) levels in human urine, plasma and cerebrospinal fluids, and their significance in studies of depression.

Both concentrations of total 3-methoxy-4-hydroxyphenylglycol (MHPG) and 3,4-dihydroxyphenylglycol (DHPG) in the human urine, plasma and CSF were determined with a high-pressure liquid chromatography with electrochemical detection in order to clarify the dynamic change in these noradrenaline metabolites. Three different biological fluids were collected simultaneously from 16 orthopedic patients who were regarded clinically as substitutes for normal subjects. In the urine, the MHPG concentrations were 1.67 +/- 0.65 micrograms/mg creatinine (mean +/- S.D.) and DHPG 0.39 microgram/mg creatinine +/- 0.21. The plasma levels were 21.16 ng/ml +/- 9.58 for MHPG, and 19.58 ng/ml +/- 8.13 for DHPG. The CSF levels of MHPG and DHPG were 24.08 ng/ml +/- 8.10 and 34.76 ng/ml +/- 11.46, respectively. The CSF levels of these metabolites were correlated significantly with those in the plasma (r = 0.852, p less than 0.001 for MHPG; r = 0.799, p less than 0.001 for DHPG), while no significant correlations were found between the urinary levels and either the plasma or CSF levels of these metabolites. In the urine, the MHPG levels were proportional to the DHPG levels, while the former were inversely proportional to the latter in the plasma or CSF. Neither the MHPG nor DHPG levels in the urine from depressed patients revealed to have any significant correlation with their clinical assessments using the Hamilton Rating Scale Score (HRS). The patients were treated with an antidepressant active selectively on the noradrenergic system, and no significant changes in urinary excretion of these metabolites were observed before and after the drug treatment. These findings suggest that in the case of psychiatric disorders such as depression, these compound levels in the plasma or CSF would provide more important information than those in the urine.

Adult↗
PubMed1986

Effect of the antiplatelet agents ticlopidine and dipyridamole on experimental immune complex glomerulonephritis in rats.

The effect of the antiplatelet agents ticlopidine and dipyridamole on immune complex glomerulonephritis in rats was evaluated. Bovine serum albumin (BSA) nephritis was induced in rats with subcutaneous immunization and intravenous dosage of BSA. Ticlopidine and dipyridamole were administered for 4 weeks before and for 7 days after onset of proteinuria. It was shown that both ticlopidine and dipyridamole could reduce the development of proteinuria when administered before the onset of proteinuria. Ticlopidine also reduced the amount of urinary protein after onset of proteinuria, and may thus be more effective against urinary protein excretion. When the antiplatelet agents were administered before onset of glomerulonephritis, blood urea nitrogen and serum creatinine levels were significantly lower, and glomerular hypercellularity and mesangial widening were milder in animals treated with ticlopidine than in controls. Glomerular deposition of BSA was less intense in treated animals than in nontreated controls. Thus, ticlopidine as well as dipyridamole was found to inhibit the development of proteinuria and glomerular alteration. It is suggested that ticlopidine could be more effective than dipyridamole against the development of immune complex glomerulonephritis in rats.

Animals↗
PubMed1986

A heat shock-resistant variant of Chinese hamster cell line constitutively expressing heat shock protein of Mr 90,000 at high level.

A heat shock-resistant variant of Chinese hamster cell line (CHO) was isolated from ethane methane sulfonate-treated CHO cells through selection by repeated exposures to elevated temperature. The variant, designated HR-01, was one to two order of magnitudes more resistant to lethal heat shock (46.0 degrees C) than the parental CHO strain (p-CHO). The heat shock resistance characteristic of this variant was stable. In addition, the HR-01 variant showed more elongated cell morphology, and was more adherent to substrate than p-CHO. When total proteins of p-CHO and HR-01 cells were compared in two-dimensional polyacrylamide gel electrophoresis, HSP90, a heat shock protein of Mr 90,000, was found to be the only protein that was expressed at a significantly higher level in HR-01 cells than in p-CHO cells. Because of the known intriguing molecular properties of HSP90, the HR-01 variant would be useful for further investigation of functions of HSP90 as well as the mechanism of acquiring heat shock resistance in mammalian cells.

Animals↗
PubMed1986

[The antiinflammatory effect of EB-382].

This study was conducted to clarify the antiinflammatory profile of EB-382, comparing it with those of ibuprofen and other antiinflammatory agents. EB-382 had a more potent inhibition on the acetic acid-induced intensive mouse intraperitoneal vascular permeability and carrageenin-induced rat hind paw edema, but a less potent inhibition on the ultraviolet-induced guinea-pig erythema and the prostaglandin biosynthesis in vitro than ibuprofen. The inhibition by EB-382 was equipotent to that of indomethacin on carrageenin-induced rat pleurisy and the zymosan air pouch, and it demonstrated a strong inhibition on the kallikrein and zymosan-induced intensive guinea-pig skin vascular permeability. EB-382 had a more effective activity on paper disk-induced granuloma and adjuvant arthritis, and it had a less potent action on the gastric mucosal membrane than ibuprofen. EB-382 had a weak action on histamine-induced rat back skin vascular permeability and heat-induced protein denaturation and hemolysis in vitro, as also shown by other test agents. The above results indicate that EB-382 will be useful as an antiinflammatory agent with a new pharmacological effectiveness besides possessing properties common to other acidic non-steroidal antiinflammatory agents in clinical studies.

Animals↗
PubMed1986

[The analgesic and antipyretic effects of a non-steroidal antiinflammatory agent, EB-382, in experimental animals].

The analgesic and antipyretic effects of EB-382 as a new non-steroidal antiinflammatory agent were examined in mice and rats. EB-382 had an equipotent inhibition to ibuprofen on the writhing syndrome caused by acetic acid, phenylquinone and acetylcholine in mice, but phenylbutazone was less potent in these experiments. EB-382 had a much more potent inhibition on the pain by the Randall-Selitto method and silver nitrate-induced arthritic pain in rats than ibuprofen and phenylbutazone. EB-382 had no analgesic effect on the pain of non-treated foot by the Randall-Selitto method in rats and by the hot-plate method in mice. EB-382 had a much more potent inhibition on the yeast-induced chronic inflammatory and adjuvant arthritic pains in rats than ibuprofen and phenylbutazone. The antipyretic activity of EB-382 was almost equipotent to that of ibuprofen in rats. EB-382 had no effect on the normal body temperature in rats, which was different from aminopyrine. The above results suggest that EB-382 will be a useful analgesic agent with an antipyretic antiinflammatory activity in clinical studies.

Animals↗
PubMed1986

Cardiovascular effects of ketanserin in conscious rabbits.

The antihypertensive effects of intravenous injection of ketanserin, a 5-HT2 receptor antagonist, were assessed in conscious rabbits. In intact rabbits, ketanserin lowered blood pressure in a dose-dependent manner. The antihypertensive effects of ketanserin were also observed in rabbits with two-kidney, one clip (2K1C) hypertension and with one-kidney, one clip (1K1C) hypertension. The effect was more marked in the 1K1C rabbits with low plasma renin activity (PRA) and high plasma norepinephrine (PNE) than in 2K1C rabbits with high PRA and normal PNE. The heart rate was not changed. Ketanserin suppressed the pressor response to exogenous norepinephrine (0.6 micrograms/Kg) 15, 30 and 45 min after the injection of ketanserin (1 mg/Kg). It also suppressed the pressor response to phenylephrine (3 micrograms/Kg) 15 min after the injection, but it did not suppress the pressor response to angiotensin II (0.15 micrograms/Kg). In order to investigate baroreceptor function, balloons were placed around the abdominal aorta and the inferior vena cava and inflated alternately. Thus, the mean arterial pressure vs heart period-logistic curve was obtained under steady-state conditions. There were no changes after the drug administration in the range of heart period and the gain (the slope at midpoint of the curve). These results suggest that the inhibition of pressor response of norepinephrine has effects in addition to a direct vasodilatory action and that an alteration of baroreceptor function is not involved in the antihypertensive effects of ketanserin.

Animals↗
PubMed1986

[A simulation study to evaluate the statistical noise and spatial resolution in image reconstruction of emission computed tomography--with respect to the optimization of the filter function in the convolution integral].

Filtered backprojection method has been commonly used to reconstruct images in the field of the computed tomography (CT). However, in the emission CT such as positron and single photon CT, poor counting static which are caused by limited dosage to patients, limited counting rate capacity and limited efficiency of the imaging device, produce a statistical noise in the reconstructed image. The magnitude of the statistical noise and the spatial resolution were evaluated for various shapes of the filter used in the convolution integrals of the filtered back-projection procedure. The statistical noise was proportional to the inverse of the root of the total number of counts for any filters. The high-frequency-cut characteristic of the filter reduced the statistical noise, but increased the spatial resolution in the images. It was possible to optimize the shape of the filter for given total number of counts and required statistical noise and spatial resolution.

Humans↗
PubMed1986

[Antibacterial activity of (+)-negamycin prepared by a new method].

Antibacterial activity of (+)-negamycin (NGM) prepared by a new method was investigated for some bacteria. The results demonstrated that this antibacterial activity of synthesized NGM was almost the same as compared to that of naturally obtained NGM, and was also effective to Pseudomonas aeruginosa harboring multiple drug resistant plasmid kR102.

Amino Acids, Diamino↗
PubMed1986

Deadtime correction method using random coincidence for PET.

A deadtime correction method is proposed for quantitative measurements in positron emission tomography. The correction is based on the observation that a deadtime loss of the random coincidence events corresponds to that of the single events and of the total coincidence events. Using the proposed correction method, the deadtime loss was kept within 1% up to the true coincidence rate of 50 X 10(3) cps per plane for a cylindrical phantom of 20 cm in diameter. Accuracy of the method is confirmed to be independent of the size of the object.

Brain↗