Search PubMed⌕ Search

Biomedical subjects

K Ohno

Publications and source records attributed to K Ohno.

At least 703 records · Page 39Linked to original sources

Fibroblasts from patients with myotonic muscular dystrophy: cholesterol requirement for proliferation and sensitivity to polyene antibiotics.

The genetic defect in myotonic muscular dystrophy (MMD) remains obscure. From the evidence that drugs blocking cholesterol biosynthesis induce myotonia and increased serum concentrations of deoxycholic acids are common among patients with MMD, evidence of the abnormal sterol metabolism in MMD fibroblasts was sought by comparing them with fibroblasts from control individuals and patients with Duchenne muscular dystrophy (DMD). Although early-onset type MMD and DMD fibroblasts have lower maximal cell densities than fibroblasts from age-matched control individuals do in medium containing 10% fetal bovine serum, we could not reveal any abnormalities in exogeneous cholesterol requirements for proliferation of MMD fibroblasts. This suggests that the sterol biosynthetic pathway in MMD fibroblasts is grossly intact. Furthermore, no difference were observed in sensitivities to polyene antibiotics, which bind to membrane sterols and presumably damage the cell membrane.

Adolescent↗

Trans-FBS-channel ventilation during the flexible bronchoscope (FBS) examination in infant.

The most important problem during FBS examination in infants is respiratory care. A new ventilation method using the channel of the FBS is proposed for respiratory care during FBS examination in infants. An FBS with a channel of more than 1.2 mm in diameter was directly inserted into the trachea under general anaesthesia without an orotracheal tube. The first step of this ventilation is the flushing of pure O2 into the lung as inspiration through the channel of the FBS. The second step is the aspiration of expiratory gas through the channel by a vacuum pump. Ventilation during the FBS examination is maintained by the repetition of these two steps by the operation of a stop-cock. Experiments in dogs, and clinical use showed that this method of respiratory care is effective and safe with certain limitations. Clinically, inspection with the FBS could be performed continuously for five minutes in most cases.

Animals↗

[Fundamental and clinical studies of cefaclor in oral surgery].

Fundamental and clinical studies on cefaclor (CCL) have been performed and the following results were obtained. CCL was orally administered to NZW rabbits at the dose of 20 mg/kg, and its concentrations in blood and various tissues of oral organs were determined. Pattern of change in its blood concentration after the administration was similar to that of change in its concentration in the tissues of oral organs. Its concentration in blood was the highest followed by gingiva, parotid gland, submandibular gland, cervical lymph node and tongue in descending order. Comparative studies of CCL against cephalexin (CEX) were conducted in 5 healthy volunteers with cross over method. The 5 volunteers were orally given 500 mg of CCL or CEX at 1 dose after meal. Peak blood levels of CCL and CEX were 14.8 micrograms/ml at 2 hours and 11.5 micrograms/ml at 3 hours, respectively. The dose of 750 or 1,500 mg/day of CCL in 3 divided doses was orally administered to 71 patients with acute purulent infections in oral tissues for 3 to 13 days. Evaluation of effect was determined by the criteria for evaluation of antimicrobial agents in oral surgery. Out of the 70 patients, excellent clinical response was observed in 18 patients, good in 40, and poor in 12. Effective rate was 83%. In vitro antibacterial activities (MIC) of CCL and CEX were studied in 74 out of 81 strains (41 from aerobes and 40 from anaerobes) isolated from 47 patients. CCL showed stronger antibacterial activities than CEX. MICs of CCL against 30 strains of Gram-positive anaerobes were distributed from 0.10 to 3.13 micrograms/ml with a peak of 0.78 micrograms/ml. As adverse reaction due to CCL, eruption was observed in only 1 patient. Laboratory tests in 61 patients who received CCL showed elevation of GOT in 1 patient and elevation of GOT and GPT in 1 patient. From the above fundamental and clinical results, CCL was considered to be a useful antibiotic for the treatment of acute purulent infections caused by aerobes and anaerobes in oral surgery field.

Adolescent↗

Functional indications for bullectomy of giant bulla.

Nineteen patients with giant bulla were followed for more than 1 year after bullectomy. They were divided into two groups according to their postoperative symptoms. Group 1 consisted of 16 patients who had no problems in their postoperative clinical course, while Group 2 included 3 patients who complained of severe dyspnea at 5 to 6 years of follow-up. Prior to operation, the forced expiratory volume in 1 sec over vital capacity (FEV1%) was 66.8 +/- in Group 1 and 27.6 +/- 5.4% in Group 2. Differences in preoperative and postoperative FEV1% were statistically significant within Group 1 and between the two groups. Postoperative FEV1% (Y) correlated significantly with preoperative FEV1% (X) (Y = 0.74X + 25.4; r = 0.836; p less than 0.001). Thus, we were able to predict the postoperative FEV1% from the preoperative value. Regional ventilation over volume was computed from the washout curve of xenon 133 after reaching equilibrium with rebreathing in a closed circuit (V/V dynamic). Group 2 had significantly lower regional ventilation over volume in all regions, both before and even after bullectomy, compared with normal subjects or Group 1 patients. Preoperative V/V dynamic was below 0.5 in all regions of Group 2. Furthermore, postoperative V/V dynamic (Y) correlated significantly with preoperative V/V dynamic (X) in the upper region (Y = 0.46X + 0.40; r = 0.638; p less than 0.02) and in the lower region (Y = 0.72X + 0.33; r = 0.869; p less than 0.001). We conclude that functional indications of bullectomy for giant bulla are that FEV1% should be greater than 40%, and that regional V/V dynamic should be greater than 0.5. On the other hand, symptomatic and functional improvement following bullectomy was reduced in patients whose FEV1% was less than 35% in whose V/V dynamic was remarkably disturbed in all regions of the involved hemithorax.

Adolescent↗

Blue light effect on proton pumping by bacteriorhodopsin.

Proton pumping in closed vesicular systems containing bacteriorhodopsin that is initiated by an orange flash, is diminished by a subsequent blue flash. This blue light effect is due to light absorbed by the photocycle intermediate M412 (M), which was formed by the orange flash. A kinetic analysis of the blue-light-induced reduction of proton pumping shows that of the two components of M, only the slowly decaying component is involved in the reduction of proton movement. This may be the first correlation between a proton movement and a specific photochemical intermediate of bacteriorhodopsin. Furthermore, we report that blue light, acting on the slowly decaying intermediate, probably causes a movement of the protons in a direction opposite to that normally seen for light absorbed by bacteriorhodopsin.

Bacteriorhodopsins↗

In situ electron microscopic observation of negatively stained tissue culture cells contaminated with mycoplasmas.

A simple, fast, and in situ method of detecting the inapparent infection of cultured cells with mycoplasmas is reported. Animal cells grown on Formvar-coated electron microscopic grids were directly fixed with glutaraldehyde, negatively stained with phosphotungstic acid and examined by transmission electron microscopy. Cells contaminated with mycoplasmas could be discriminated from uncontaminated cells. The micro-organisms in the negatively stained preparations corresponded with those revealed by thin sectioning, and the distribution of mycoplasmas in cultured cells coincided with those revealed by the Hoechst staining method. Most of the highly resolved mycoplasmas were polymorphic, and closely associated with host cells; often more than 500 organisms per host cell were seen.

Animals↗

Muscarinic cholinergic receptors of the convulsive strain (E1) mouse.

The biochemical characteristics of the muscarinic acetylcholine receptors were studied on the E1 strain mouse brain by the binding assay using [3H]1- quinuclidinyl benzylate. Scatchard analyses showed that the receptor density (Bmax) of the hippocampus significantly decreased by 26.4% and the affinity (Kd) increased by 18.8% in E1(+) compared to dd-Y. It is suggested that this hippocampal subsensitivity found in E1(+) mouse might be strain-specific, because repeated megimide convulsions failed to produce the same down regulation.

Animals↗

Renal function study with 111In-DTPA--in comparison with 99mTc-DTPA.

Technetium-99m-diethylene-triamine-penta-acetic acid (DTPA) and 111In-DTPA were injected simultaneously into 21 patients with various levels of renal function. Scintiphoto, camera data renograms and clearance values (plasma sampling) were obtained for each patient. The mixed isotope scintiphoto images were of intermediate quality and the images with 111In-DTPA were apparently inferior to those with 99mTc-DTPA. These equations were obtained: (1) y = 0.30 + 0.91 x (coefficient of correlation r = 0.98) where x is the value at T peak (time of maximum count on renogram) obtained with 99mTc-DTPA and where y is the value at T peak with 111In-DTPA. (2) y = -0.09 + 1.006 x (r = 0.99) where x is the value at T3/4 (time interval between the time of maximum count to the time of 3/4 of maximum count on renogram) and where y is the value at T3/4 obtained with 111In-DTPA. (3) y = -0.01 + 1.007 x (r = 0.98) where the x and y values were for the excretion ratios (counts at 20 min/maximum counts on renogram). (4) y = 0.81 + 0.98 x (r = 0.99) where x and y are the clearance values.

Female↗