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Biomedical subjects

K Haraguchi

Publications and source records attributed to K Haraguchi.

At least 145 records · Page 8Linked to original sources
PubMed1989

[Analysis of PCB- and PCT-methylsulfones in the blood in yusho patients].

Polychlorinated biphenyl (PCB)- and terphenyl (PCT)-methylsulfones were isolated from the blood of yusho patients sampled in 1987 and characterized by gas chromatography with mass spectrometry (GC/MS), electron capture detection (GC/ECD) and flame photometric detection (GC/FPD). GC/MS analysis for PCB-methylsulfones showed that all the blood tested (nine samples) contained the tri- and tetrachloro congeners. The concentrations of PCB-methylsulfones were estimated to be 15-120 ppb. PCT-methylsulfones detected in the same fraction, which were confirmed by GC/MS comparison with authentic samples as well as by GC/ECD and GC/FPD, consisted of tetra-, penta- and hexachloroterphenyl methylsulfone congeners. The levels of PCT-methylsulfones in six samples detected were preliminarily estimated to be 10-270 ppb, on the basis of a PCB-methylsulfone standard. Their origins and biological effects are unclear at present.

Food Contamination↗
PubMed1989

[The effectiveness of GaA1As semiconductor laser treatment to pain decrease after irradiation].

Recently, sedative and antiphlogistic treatment is conducted with low energy laser irradiation. The purpose of the this study was to evaluate the effectiveness to decrease of pain just after irradiation by a GaA1As semiconductor laser. The irradiation apparatus was SEMI LASER NANOX (LX-800: G-C. Co.) with the following features: a wave length of (around) 780nm: the laser energy, 30mW; exposure time, 30sec to 180sec/per treatment. Diagnosis of pre- and post-operative sensitivity were classified into the following four grades: Grade 0 no pain. Grade I mild pain. Grade II strong but tolerable pain. Grade III intolerable pain (simultaneous with stimulation). The results were as follows: 1. In the hypersensitivity of dentin, the treatment was not effective with 2 cases of grade III, but with all of grade I, II (35 cases) the pain decreased just after irradiation. 2. It was effective in all cases with pain like periodontitis after root canal filling and pain after extraction of teeth. 3. It was effective in all cases with gingivitis, stomatitis, and gingival ulcers after infiltration anesthesia etc..

Adolescent↗
PubMed1989

[Simulation with a pre-clinical training system. 1. Practice in operative dentistry using an experimental manequin articulator, jaw model, and artificial teeth].

Clinical practice with patients is the most important part of education for dental students. However there are considerable difference between lecture, basic practice, and clinical practice. Therefore it is difficult to go from basic practice to clinical practice. To overcome this, we developed and introduced a Pre-Clinical Training system using a newly designed manequin, articulater, jaw model, and artificial teeth. This manequin is very similar to patients in appearance. The mandibular part used a semi-adjustable arcon type articulator. The artificial teeth were made of two types of synthetic resins with different hardness for use in operative dentistry. The teeth also have caries areas made of soft black resin. Using this system, the students practiced oral examination, cavity preparation and restoration in operative dentistry.

Dental Articulators↗
PubMed1989

[Simulation with a pre-clinical training system. 2. Evaluation of the pre-clinical training system].

This study evaluated usefulness of the Pre-Clinical Training System. Undergraduate students and instructors at Higashi-Nippon-Gakuen University practiced class I composite resin restoration of the lower right first molar using the system. After the practice, they filled out questionnaires to evaluate the system. According to the results, this system proved useful for pre-clinical education though there is room for improvement.

Dental Restoration, Permanent↗
PubMed1988

Evidence for a preferential iodination site within the thyroglobulin molecule.

Mouse 330 kDa thyroglobulin labeled in vivo was analyzed using a tryptic peptide mapping technique and high performance liquid chromatography (HPLC). 30 min after Na125I injection, one peptide spot (spot 7) on a silica gel plate was the only prominent labeled peptide, followed by other labeled peptide spots after 1 h. HPLC showed that spot 7 was rich in monoiodotyrosine. The ratios between the iodoamino acids were strictly maintained from 1 to 6 h after Na125I injection. Spot 7 was again the first spot that appeared from the samples of iodine-deficient mice. These data indicate that there is some preferential iodination site(s) within the thyroglobulin molecule and also that their iodoamino acid composition is predetermined.

Amino Acids↗
PubMed1988

Effects of thyrotropin, carbachol, and protein kinase-C stimulators on glucose transport and glucose oxidation by primary cultures of dog thyroid cells.

Thyroid glucose metabolism can provide NADPH and H2O2 for thyroid hormone synthesis. Several agents stimulate glucose oxidation in thyroid slices, but little is known about glucose transport in this tissue. In the present study, various thyroid stimulators were tested on glucose transport and oxidation using primary cultures of dog thyroid cells. After preincubating the cells with the agonists, glucose uptake was measured by adding 2-deoxy-D-[1-3H]glucose [( 3H]2-DOG) for 5 min, and glucose oxidation was assessed during a single 60-min incubation with agonist and D-[1-14C]glucose. TSH (0.1-10 mU/ml), 12-O-tetradecanoyl phorbol-13-acetate (TPA; 10(-8)-10(-6) M), and carbachol 10(-6)-10(-2) M) stimulated [3H]2-DOG transport and glucose oxidation in a dose-dependent manner. The effect of TSH appears to be mediated by cAMP, since N6,2'-O-dibutyryl cAMP, 8-bromo-cAMP, cholera toxin, and isobutylmethylxanthine also stimulated [3H]2-DOG transport. Norepinephrine, which had no effect by itself on either transport or oxidation, inhibited TSH stimulation of [3H]2-DOG transport via an alpha 2-adrenergic receptor. The mechanism of the TPA and carbachol effect does not involve cAMP. A combination of maximal amounts of TSH or bromo-cAMP and carbachol or TPA produced additive effects on transport, while addition of TPA with carbachol produced no such additive effect. Kinetic analysis of 2-DOG transport indicated that all three agonists reduced the Km and increased the maximum velocity. Basal 2-DOG transport was increased in Ca2+-free medium, with or without EGTA, or in the presence of calcium channel blockers such as La3+ or Mn2+. In the presence of such increased basal glucose transport, TSH further stimulated it when Mn2+ was used, had no effect in Ca2+-free buffer plus EGTA, and caused an inhibition with La3+. Such inhibition was not caused when N6,2'-O-dibutyryl cAMP was used in the presence of La3+. Carbachol and TPA did not stimulate transport when the Ca2+ channel blockers were used, but a small increase was seen in Ca2+-free buffer containing EGTA. TSH stimulation of cAMP production was also diminished in the presence of La3+, but enhanced in the presence of Mn2+. The calmodulin inhibitor W-7 and the intracellular Ca2+ blocker 8-N,N-diethylamino octyl-3,4,5-trimethoxybenzoate hydrochloride diminished the stimulation of [3H]2-DOG transport and glucose oxidation induced by TSH, carbachol, and TPA. These data indicate that thyroid glucose transport and glucose oxidation are regulated by both cAMP-dependent and cAMP-independent systems.

1-Methyl-3-isobutylxanthine↗
PubMed1988

Determination of vanillylmandelic acid, vanillactic acid, and homovanillic acid in dried urine on filter-paper discs by high-performance liquid chromatography with coulometric electrochemical detection for neuroblastoma screening.

We report a method for determination of vanillylmandelic acid, vanillactic acid, and homovanillic acid by high-performance liquid chromatography (HPLC), with coulometric electrochemical detection, for mass screening of neuroblastoma. Urine samples were collected on filter paper, dried, and then pretreated. The chromatographic procedure is reliable and fast, allowing for a large sample throughput for routine screening. Intricate extraction procedures and centrifugal separation are unnecessary. Screening for neuroblastoma by HPLC is rapidly gaining acceptance in Japan, and our method is being used at many screening centers. Of 26,571 infants screened in one year in Yokohama City, our method detected five with neuroblastoma.

Chromatography, High Pressure Liquid↗
PubMed1987

Aesthetic camouflage of bilateral cleft lip scars.

Two operative scar lines remain after bilateral cleft lip repair. A method has been devised in which the two scar lines are reduced into one. The characteristics of this method include (1) an inconspicuous scar, (2) elevation of the nasal tip using the prolabium, (3) repair of the whistling deformity, (4) a natural-looking mustache, (5) formation of a pout, and (6) psychological benefits. Good results have been obtained with this method. The disadvantage of this method is the maxillary retardation. However, this does not occur in adults and can be corrected easily in children.

Adolescent↗
PubMed1987

Demonstration of calcium-dependent proteases (calpains) and thyroglobulin proteolysis in hog thyroid cytosol.

Ca2+-dependent neutral proteases in hog thyroid cytosol were found to digest thyroglobulin. The protease activity was divided into two peaks by DEAE-cellulose column chromatography. Peak I was eluted at 0.2 M NaCl and required only a micromolar range of Ca2+ for its 50% activation, while peak II, which was eluted at about 0.4 M NaCl, displayed little activity until the Ca2+ concentration was increased at more than 10(-4) M. Among various inhibitors used, thiol protease inhibitors (leupeptin, E-64 and monoiodoacetic acid) were the most effective, whereas a calmodulin antagonist (trifluoperazine) and serine protease inhibitors (phenylmethyl-sulfony-fluoride and pepstatin A) were not effective, indicating that these Ca2+-dependent proteases corresponded to calpains 1 and 2. Among the substrates tested, casein was the best and thyroglobulin was also a good for calpain 2. By using immunoblotting procedure with anti-thyroglobulin antibody, it has been found that calpain 2 degrades thyroglobulin to yield 67 K and 46 K thyroglobulin and further that it also degrades 40 K thyroglobulin.

Animals↗
PubMed1986

Capillary gas chromatographic analysis of methylsulphone metabolites of polychlorinated biphenyls retained in human tissues.

Structures and concentrations of methylsulphone (MSF) metabolites of polychlorinated biphenyls (PCBs) retained in the liver, lung and adipose tissue of a yusho patient and of a normal person were studied using capillary gas chromatography coupled with electron-capture detection or mass spectrometry. More than 60 isomers of tri-, tetra-, penta- and hexachloro-MSF-biphenyls were detected in the lung of the yusho patient, and the gas chromatographic peaks coincided with those of 40 authentic isomers in retention times by three separate capillary columns, when they were compared with those of 86 synthesized reference compounds. The main components of MSF-PCBs identified in the Yusho patient were 4-MSF-2,5,4'-tri-, 4-MSF-2,5,2',4'-tetra-, 4-MSF-2,5,2',5'-tetra-, 3-MSF-4,5,2',3'-tetra-, 4-MSF-2,5,2',3',4'-penta- and 4-MSF-2,5,2',4',5'-pentachlorobiphenyls, estimated to be 0.7-1.5 micrograms/kg in the lung and 0.3-1.5 micrograms/kg in the adipose tissue.

Adipose Tissue↗
PubMed1986

Formation of triazene from sulphonamide and nitrite in acidic solution.

Formation of triazene derivatives from sodium nitrite and sulphanilamide, sulphamethizole or sulphamethoxazole in acidic solution containing saliva or canned vegetable juice was studied using reverse-phase high-performance liquid chromatography with ultraviolet light detection at 365 nm. At the optimal pH of 3.2-3.7, the mean yield of the triazene formed by reaction of sulphanilamide and nitrite in saliva was 28.8%, calculated on the nitrite content, and there was a high positive correlation (r = 0.993) between the nitrite concentration in the saliva and the triazene yield. In contrast, at the optimal pH values for triazene formation from sulphamethizole and sulphamethoxazole (3.0-3.5 and 2.5-2.9 respectively), triazene yields were much lower, accounting for only 0.9 and 1.0%, respectively, of the nitrite present. Triazene formation was partly inhibited in the presence of vegetable juice.

Chromatography, High Pressure Liquid↗