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Biomedical subjects

M Itoh

Publications and source records attributed to M Itoh.

At least 721 records · Page 40Linked to original sources

Studies on thermophile products. VI. Activation of mouse peritoneal macrophages by bis(2-hydroxyethyl) trisulfide.

The biological effects of a cytotoxic substance (BS-1), isolated from Bacillus stearothermophilus UK563 and identified as bis(2-hydroxyethyl) trisulfide, on elicited mouse peritoneal macrophages induced by a casein injection, were investigated in vitro. BALB/c mouse macrophages treated or pretreated with BS-1 (1-10 micrograms/ml) showed cytotoxicity against syngeneic DBA/2 mouse P815 mastocytoma. BS-1 also showed weak cytotoxicity directly against P815 in the absence of macrophages. BS-1 significantly increased the glucose consumption of macrophages without producing cytotoxicity. This trisulfide compound increased nitric oxide formation, interleukin-1 production and prostaglandin E2 release in macrophages. It did not, however, increase the production of active oxygen species in macrophages, but it reduced cytochrome c in the presence of phagocytes. These results indicate that BS-1 activates macrophages to the cytolytic stage.

Animals↗

[A method employing housing in a radial maze apparatus for estimating working memory in mice: effects of scopolamine and delay upon maze performance].

Male ddY mice were housed in a 4-, 6-, or 8-arm radial maze apparatus for 6 hr a day and then removed to a normal cage for fasting until the next day's trial. A water bottle was placed at the central platform. The end of each arm ran to the home cage through a guillotine door (G). Food was placed in the home cage. During the housing in the apparatus, one G was opened, and the remaining Gs were shut. The opened G was changed in random order during the housing period of 6 hr. At the beginning of the trial, all Gs were shut. The mouse was placed on the platform and was permitted to choose the arms until it chose all arms. When the mouse chose the last arm, the G was opened to allow stepping into the home cage. The mice housed in these apparatus learned to go to the home cage without entering already chosen arms within 4-6 days. Scopolamine (0.2 and 0.4 mg/kg, i.p.) impaired the maze performance. A 1- to 4-min delay impaired the performance slightly, but did not show any significant effect depending on the delay intervals. These results suggest that the apparatus is a useful and easy method for estimating working memory and the drug effects thereon in mice.

Animals↗

Effect of monensin on DNA synthesis in cultured human thyroid cells.

Monensin is a carboxylic ionophore which perturbs the structure and function of the Golgi apparatus and lysosomes. In the present study, we investigated the functional significance of these organelle in the growth factor-mediated cell proliferation in cultured human thyroid cells from normal and Graves' disease. DNA synthesis was estimated by [3H]-thymidine uptake and flow cytometric analysis. Monensin inhibited both [3H]-thymidine uptake in a dose-dependent manner and the transition of G1 to S phase determined by flow cytometric analysis. Monensin partially blocked the effect of bovine TSH in normal thyroid cells. [3H]-thymidine uptake was suppressed to 56.7 +/- 37.3% of the control value with bTSH and monensin, but it was still higher than those with monensin alone (21.9 +/- 15.0% of the control). The percentage of cells in the S phase was also increased from 7.64 +/- 1.91% with monensin alone to 11.54 +/- 2.82% with bTSH at t = 24h. Forskolin or 12-O-tetradecanoylphorbol 13-acetate (TPA) could not mimic the action of TSH. On the other hand, insulin and EGF most effectively counteracted monensin-induced inhibition of DNA synthesis in Graves' thyroid cells. [3H]-thymidine uptake was not completely inhibited, being 73.5 +/- 24.0% with EGF, 105.0 +/- 25.4% with insulin, and 49.2 +/- 6.6% with monensin alone, respectively. The percentage of cells in the S phase also increased from 8.31 +/- 2.61% with monensin alone to 11.25 +/- 4.27% with EGF and 12.86 +/- 3.12% with insulin. In conclusion, the functional maintenance of the Golgi apparatus and lysosomes is necessary for DNA synthesis in both normal and Graves' thyroid cells, in which bTSH, insulin, and EGF might be differently involved in the regulation of DNA synthesis.

Cell Cycle↗

Stimulation of rat placental lactogen-II (rPL-II) secretion by cultured trophoblasts by insulin: development of a rat placental cell culture system and effects of peptide hormones on rPL-II secretion in vitro.

The purpose of this study was to develop a primary culture system using serum-free medium for rat placental trophoblast cells and to investigate the factors that control rat placental lactogen-II (rPL-II) secretion in vitro. The placentae of day 13 pregnant rats were dissociated in Medium 199 containing 0.1% collagenase and 0.002% DNAase. Dissociated cells were fractionated into five segments by centrifugation through a 40% Percoll density gradient and incubated on rat tail collagen bed in medium SFM-101 for up to 7 days. Fraction B at the Percoll gradient density of 1.05 g ml-1 was enriched with rPL-II-producing cells and the time course of rPL-II secretion was characterized by a rapid increase in the first 2 days, remaining at high values (mean: 14-16 ng micrograms-1 DNA) for the following 2-3 days and decreasing thereafter. The rPL-II-producing cells from faction B identified by immunocytochemical examination accounted for approximately 69% of total cultured cells and consisted of a few giant cells and polygonal cells. Growth factors (bovine insulin, 0.1-20 micrograms ml-1; recombinant human insulin-like growth factor (IGF)-I, IGF-II, 0.1-1.0 micrograms ml-1; murine epidermal growth factor (EGF), 0.001-10 micrograms ml-1), rat pituitary hormones (rat growth hormone, rat prolactin, 0.1-10 micrograms ml-1) and hypothalamic hormones (human growth hormone-releasing hormone (GHRH), corticotrophin-releasing hormone (CRH), LHRH, 0.1-10 micrograms ml-1) were individually added to the culture medium to investigate the putative factors that directly control rPL-II secretion by the trophoblast cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Clinical characteristics and hearing recovery in perilymphatic fistulas of different etiologies.

Clinical features and hearing recovery were compared between three types of perilymphatic fistula groups; surgically confirmed (PLF-conf, n = 16), suspected (PLF-susp, n = 24) and traumatic (trauma-PLF, n = 11). Initial average hearing level was best in the PLF-susp group (50.9 dBHL), followed by the trauma-PLF (55.7 dBHL) and PLF-conf (59.7 dBHL) groups, though the difference was not significant (ANOVA, p > 0.05). Of 51 patients, 27 cases were operated on and fistula was confirmed in 19 ears (70.4%). Conservative treatment, including bed rest and medication, was given to all patients. After the treatment, meaningful hearing recovery was obtained only at 1 kHz in the PLF-conf group (paired t-test, p < 0.05). However, significant recovery was seen at all frequency ranges (0.125-8 kHz) in the PLF-susp group (average, 16.8 dB; p < 0.01), while hearing improvement was intermediate for the trauma-PLF group. The initial hearing level and the period until the start of treatment strongly correlated with the final hearing level. Although 27 patients (47%) complained of dizziness, the prognosis for vertigo is excellent as noted by other authors. It was concluded that if conservative treatment is started early for PLF patients with mild hearing loss, hearing recovery can be ensured.

Adult↗

[Transurethral ureterolithotripsy with rigid ureteroscope--efficacy of balloon dilation of ureteral orifice and intramural ureter].

In order to minimize the late complications of transurethral ureterolithotripsy with a rigid ureteroscope such as distal ureteral stricture or vesicoureteral reflux, we have performed a balloon dilation of the ureteral orifice and the intramural ureter prior to insertion of a rigid ureteroscope in 62 cases with ureteral calculi between October 1986 and December 1991. A 7F balloon dilator (Bard Co. USA) was cystoscopically inserted into the ureter over a 0.038 inches Radifocus guide wire (Terumo Co., Japan) and then, a balloon was inflated to 15F size with saline using a 10 ml disposal syringe. Thereafter, an 11.5F rigid ureteroscope (Wolf Co., Germany) was inserted instead of a balloon dilator. The stone was disintegrated and removed by ultrasonic lithotripter, electrohydraulic lithotripter and/or basket forceps. The stone was removed completely in 45 cases (72.6%) and incompletely in 10 (16.1%). In 7 cases (11.3%), the stone removal was failed. Long-term follow up with an excretory urography obtained at 6 months or later in 31 cases showed no distal ureteral stricture. Voiding cystography was performed in 33 cases at a mean 2.8 months postoperatively and no vesicoureteral reflux was observed. In control group, 309 cases were treated with transurethral ureterolithotripsy without dilation of the ureteral orifice and the intramural ureter between the same period. A complete removal was achieved in 262 cases (84.8%) and an incomplete removal in 16 (5.2%). 31 (10%) was failed. Distal ureteral stricture due to this procedure was found in 3 cases (2.1%) in 141 long term followed up cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Building areas of hospitals in Japan and distribution of areas by department--1980's.

(1) Areas of entire hospitals which have been continuously increasing in the past 30 years are finally showing signs for slowing down. The areas of the hospitals completed in the 1980's were generally 50 to 80 m2 per bed. (2) The distribution of the nursing department to the entire hospitals in area ratio ranges from 30 to slightly more than 40%, or higher than 35% in most cases. The actual areas of the nursing department has surpassed 20 m2 per bed in a considerably large number of hospitals. (3) The area ratio of the outpatient department tends to concentrate to about 12%. Of this percentage, in almost all hospitals, the proportion of the emergency division was less than 2%. (4) As in the 1970's, the diagnostic and treatment facilities were within the range of 18 to 22% in the majority of the hospitals. The distribution shifted to ratios higher than the previous survey. The distributions for the various sections are as follows: 1) Specimen test rooms 3 to 5% 2) Physiological examination rooms slightly below 1% to slightly above 2% 3) X-ray diagnosis rooms about 4% 4) Radiation therapy rooms about 1% 5) Nuclear medicine rooms about 1% 6) Operating department 3 to 5%, 2 to 3 m2/bed 7) Delivery suite less than 1% 8) Rehabilitation department 1 to 4% 9) Hemodialysis suite about 1% (5) The area ratios of the supply department dispersed substantially between 12 and 25%. About 70% of the hospitals remained in the range of 15 to 20%. The ratios of the various sections in the department are as follows: 1) Pharmacy: slightly less than 2% to slightly less than 3% 2) Central sterile and supply department: about 2% 3) Blood bank: installed in hospitals with more than 500 beds 4) Kitchen: slightly more than 2% to slightly more than 3%, 1.5 to 2.5 m2/bed 5) Laundry: less than 1% 6) Central storage and material hundling unit: about 1% 7) Mechanical plant: 5 to 13% (6) The administration department allocates 7 to 14% of its area to the management division and 2 to 6% to the welfare division.

Data Collection↗

[Immunological aspects of asthmatic children in remission].

Allergen-activated T cells secrete several kinds of bioactive lymphokines such as IL2, IL3, IL4, IL5 and IFN-gamma. They function as helpers in IgE production involved in immediate type hypersensitivity and/or effector cells in delayed type hypersensitivity in allergic patients. The acquisition of interleukin 2 (IL2) responsiveness by specific antigen-stimulated cells is generally an essential event for the induction of specific immunological phenomena. To investigate the immunological changes in asthmatic children in remission, the induction of IL2-responsiveness and production by Df (Dermatophagoides farinae)-stimulated patient lymphocytes, and Df-induced IFN-gamma production by patient lymphocytes were evaluated. The patients were divided into 3 groups. The remission group (I) consisted of those patients who had had no or only a few asthmatic attacks for more than 2 years without medication. The group of active asthma were divided into 2 groups according to attack frequency and severity (II, partial remission; III, active asthma). IL2 responsiveness and production by Df-stimulated lymphocytes from group II and III were increased. As symptoms improved, the extent of the response subsided to a level comparable to that of normal individuals (group III). IFN-gamma production by Df-stimulated lymphocytes from patients with active asthma was lower than that of normal lymphocytes. In contrast, lymphocytes from patients in complete remission group (I) induced far greater IFN-gamma generation than those from normal and group II and III patients in a Df antigen-dependent manner, which might downregulate Df-induced hyperreactivity for Df-mediated allergic response.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Successful pregnancy in a patient with heart failure secondary to aortic and mitral regurgitation.

In this report, maternal and fetal risks were evaluated in a pregnant patient who had no previously established heart valvular disease. A 41-old-year patient with aortic and mitral regurgitations suffered from progressive congestive heart failure during 20 weeks of gestation. She carried the pregnancy to a successful delivery at 31 weeks. During this time, sudden deterioration in the symptoms occurred, but both the fetal and maternal outcomes were uneventful. This experience of a good outcome may contribute to the future management of pregnancies associated with heart disease.

Adult↗

Fractal dimension analysis of aluminum oxide particle for sandblasting dental use.

Aluminum oxide particles are commonly used as a sandblasting media, particularly in dentistry, for multiple purposes including divesting the casting investment materials and increasing effective surface area for enhancing the mechanical retention strengths of succeedingly applied fired porcelain or luting cements. Usually fine aluminum oxide particles are recycled within the sandblasting machine. Ceramics such as aluminum oxides are brittle, therefore, some portions of recycling aluminum oxide particles might be brittle fractured. If fractured sandblasting particles are involved in the recycling media, it might result in irregularity metallic materials surface as well as the recycling sandblasting media itself be contaminated. Hence, it is necessary from both clinical and practical reasons to monitor the particle conditions in terms of size/shape and effectiveness of sandblasting, so that sandblasting dental prostheses can be fabricated in optimum and acceptable conditions. In the present study, the effect of recycling aluminum oxide particles on the surface texture of metallic materials was evaluated by Fractal Dimension Analysis (FDA). Every week the alumina powder was sampled and analyzed for weight fraction and contaminants. Surface texture of sandblasted standard samples was also characterized by FDA. Results indicate very little change in particle size, while the fractal dimension increased. Fractal dimension analysis showed that the aluminum oxide particle as a sandblasting media should be replaced after 30 or 40 min of total accumulated operation time.

Air Pressure↗

[Analysis of immunosuppressive activity of lecithin-bound iodine (LBI) on antigen-induced IL2 responsiveness in peripheral blood lymphocytes from patients with allergic diseases].

The effect of lecithin-bound iodine (LBI) on antigen-induced IL2 responsiveness, useful in in vitro test for the detection of etiological antigen and disease activity in allergic diseases, was investigated. In peripheral blood mononuclear cells (PBMC) from asthmatic children, LBI suppressed Dermatophagoides farinae (Df)-induced IL2 responsiveness in a dose dependent manner, in a range of 0.01 to 100 micrograms/ml. Similarly, LBI also suppressed ovalbumin (OVA)-induced IL2 responsiveness in PBMC from patients with atopic dermatitis, sensitized with OVA, in concentration of 0.1 to 100 micrograms/ml. Moreover, purified protein derivative (PPD)-induced IL2 responsiveness was equally inhibited by LBI, at doses of between 0.1 and 100 micrograms/ml. However, LBI could not overcome the responses induced by concanavalin A (Con A) until it reached unphysiological concentrations of as high as 100 micrograms/ml. The fact that antigen-induced IL2 responsiveness was suppressed by LBI at concentrations comparable to blood levels of LBI in individuals medicated suggests that LBI is a weak immunosuppressant. IL2-responding T cells were more sensitive to LBI than antigen-presenting cells in Df-induced IL2 responsiveness, although LBI suppressed both cell populations. Taken together, LBI could work as a weak immunosuppressant to inhibit lymphocyte responses to allergen and to improve clinical status in allergic diseases, including bronchial asthma caused by Df and atopic dermatitis provoked by OVA.

Antigens↗

Human chromosome 8 (p12-->q22) complements radiosensitivity in the severe combined immune deficiency (SCID) mouse.

The severe combined immune deficiency (SCID) mouse shows two kinds of phenotypic abnormalities, a high radiosensitivity and an abnormal immunoglobulin gene recombination. A genetic study has revealed that a mutation exists in chromosome 16. However, several attempts to isolate the gene responsible for these phenotypes have been unsuccessful. By making use of the characteristics of radiosensitivity, we conducted complementation experiments to identify a human chromosome which contains the responsible gene. Radioresistant cells were selected from the hybrid cells of the SCID mouse and human fibroblasts. Based on this approach, the gene complementing the SCID phenotype was assigned to human chromosome 8 p12-->q22.

Animals↗

[Measurement of bile CEA levels in patients with colorectal cancer: is it of value for diagnosis of occult liver metastases aiming at prophylactic regional hepatic chemotherapy?].

A preliminary study was conducted to determine whether the measurement of CEA levels in gallbladder bile would be of value for diagnosis of occult liver metastases aiming at prophylactic regional hepatic chemotherapy in patients with colorectal cancer. Forty-fold dilution by normal human sera was necessary to measure CEA levels of gallbladder bile by the enzyme immunoassay (EIA). Bile CEA levels were 27.2 +/- 30.4 (M +/- SD) ng/ml in patients with benign biliary diseases (control), 248.5 +/- 426.3 ng/ml (p < 0.05, vs. control) in Dukes B, C patients, and 3,331.5 +/- 4,473.3 ng/ml (p < 0.01 vs. control, p < 0.05 vs. Dukes B, C) in patients with hepatic metastases from colorectal cancer, respectively. Bile CEA tended to demonstrate the existence of hepatic metastases more accurately than serum CEA. Our results obtained from a small number of patients suggest that patients with either elevation of bile CEA level or with a high ratio of bile CEA/serum CEA may be candidates for hepatic recurrence that requires prophylactic hepatic chemotherapy. However, it may be difficult to determine the bile CEA level at which occult liver metastases are demonstrated.

Bile↗

[Diurnal secretion profile of melatonin in epileptic children with or without photosensitivity and an observation of altered circadian rhythm in a case of completely under dark living condition].

Diurnal secretion profile of melatonin was studied by measuring multiple serum melatonin levels in three photosensitive epileptic children (group P) and eleven epileptic children without photosensitivity (group E). In the group E patients a normal fluctuation pattern of serum melatonin levels was observed; low and stable during daytime and rapidly elevating and high in the night. Five out of eleven patients took midday naps, which did not cause any change of serum melatonin level, remaining at the low baseline level. In 2 out of 3 patients in group P, nocturnal peak levels were far lower than those in group E. The third case with severe photosensitive epilepsy was kept in a dark room with the aim of avoiding slightest light stimuli that may provoke seizures. During the period of the dark room therapy extending over 105 days, her circadian rhythm of sleep-wakefulness was prolonged from 24.00 hours to 24.27 hours. Nocturnal increment of melatonin was observed in this case. It was concluded that an endogenous circadian rhythm is operating in the melatonin secretion and that this mechanism is intact in epileptic children irrespective to the presence or absence of photosensitivity.

Child↗

[The cranial MRI in severe cerebral palsy: a comparative study with clinical data].

The magnetic resonance examination was performed in 38 patients with severe cerebral palsy (CP; 15 males and 23 females) who had both motor delay (unable to move anywhere) and mental retardation (I. Q or D. Q below 30). Neuroimaging findings were compared with the CP type, etiology, and grade of understanding of language. Cranial magnetic resonance imagings (MRI) in CP were divided into five types. Type 1 : nine predominantly showed cyst-liked ventricles and periventricular hyperintensity on T2-weighted imaging (PVH) and only scarred basal ganglia and thalamus were visible. All suffered from neonatal asphyxia and the clinical type was rigospastic tetraplegia (RST). Type 2: eleven predominantly showed PVH and hyperintensity on T2-weighted (HT2) in basal ganglia and thalamus. All suffered from neonatal asphyxia and the clinical type was RST or rigospastic diplegia. Type 3: five showed PVH and three had cortical atrophy. All suffered from neonatal asphyxia and the clinical type was spastic diplegia. Type 4: four predominantly showed HT 2 in putamen and thalamus. Three had cortical atrophy. All suffered from neonatal asphyxia. The clinical type was athetotic CP (ATH). Type 5: nine predominantly showed HT 2 in globus pallidus. Four had cortical atrophy and two had hippocampal atrophy. All suffered from neonatal jaundice and the clinical type was ATH. All patients who suffered from neonatal asphyxia and spastic CP had MRI in PVH. All patients who suffered from neonatal asphyxia and ATH showed HT 2 in putamen and thalamus. Almost patients who suffered neonatal jaundice and ATH showed HT 2 in globus pallidus. With athetotic CP, cases with atrophy of the cerebral cortex or/and hippocampus were lower grade of understanding of language than no atrophy of both. The result of studies of MRI are in agreement with neuropathological findings.

Adolescent↗

[Polysomnographical studies of a patient with severe myoclonic epilepsy in infancy].

In order to evaluate the brain function of a boy with severe myoclonic epilepsy, we performed serial polysomnographical studies. Although percent slow wave sleep and percent stage REM were normal in infancy, they were reduced with age after 1 year old. Concomitant existence of twitch movements and localized movements of mentalis muscle with REMs bursts, which decreased rapidly during infancy in healthy controls, were paradoxically increased with age in this patients. Since sleep parameters are thought to be controlled by the brainstem neural system, the present observations indicate that the brainstem function of this patient is deteriorated progressively at least during childhood.

Child, Preschool↗

[A patient with lysosomal glycogen storage disease with normal acid maltase].

A 13-year-old boy with mental retardation developed idiopathic cardiomyopathy and glycogen storage myopathy, but with normal lysosomal enzyme activities, consistent with a syndrome of lysosomal glycogen storage disease with normal acid maltase coined by Danon et al (1981). He was in good health except for WPW syndrome diagnosed at 7 years of age. He had heart murmur with abnormal ECG, elevated serum GOT, GPT, LDH, CK and aldolase levels. An echocardiogram showed obstructive hypertrophic cardiomyopathy. Lysosomal enzyme activities including acid alpha-glucosidase in fibroblasts were within normal limits. In the biopsied biceps brachii muscle, there was a mild variation in fiber size. An approximately 10 percent of myofibers had tiny vacuoles which contained periodic acid Schiff positive granules and were slightly high in acid phosphatase activity. The vacuoles were encircled by membranes with high neuron specific enolase (NSE) and acethylcholin-esterase (AchE) activities. On electron microscopy, numerous autophagic vacuoles scavenging glycogen granules were recognized as seen in acid maltase deficiency. Because the vacuolar membranes were high in NSE and AchE activities, lysosomal membrane formation from the cell membrane may be defective. When one has a patient with mild to moderate mental retardation, idiopathic hypertrophic cardiomyopathy and high serum CK level, muscle biopsy must be performed to rule out the present disorder.

Adolescent↗

[The establishment of a monolayer culture system of guinea pig chief cells and an enzyme immunoassay system for guinea pig pepsinogen].

For the purpose of studying pepsinogen secretion from gastric chief cells, we established a monolayer culture system of guinea pig chief cells and an enzyme immunoassay (EIA) system specific for guinea pig pepsinogen. Dispersed chief cells were obtained from gastric mucosa of a guinea pig using collagenase, GEDTA, and Percoll solution, suspended in DMEM/F-12 (1/1 containing 10% FCS) media, and cultured for 70hr. Then the monolayer culture system was established. Pepsinogen was purified from gastric mucosa of a guinea pig using DEAE-Sephacel and Sephacryl S-200 columns. Antibody to pepsinogen was raised by immunizing rabbit with the purified pepsinogen. A two-site EIA system was then established using beta-galactosidase-labeled Fab' antibody. The EIA system showed sensitivity to measure above 1.5ng of guinea pig pepsinogen, and the monolayer culture system responded well to secretagogues. These systems are useful for studying pepsinogen secretion.

Animals↗