[An experimental examination of extra-hepatic metabolism of trichloroethylene in dogs]

To investigate the extra-hepatic organs metabolism of trichloroethylene, the extra-hepatic circulation in dogs was established by operating on the portal vein-right femoral vein bypass and other locations. These dogs were exposed for one hour to trichloroethylene at concentrations of 700 ppm. Metabolite (trichloroethanol (F-TCE), trichloroacetic acid (TCA) and total trichloroethanol (T-TCE) changes in serum and urine were measured from the beginning of exposure until one hour after termination, and compared with previous data as control. The following results were obtained. This operation method gave a very slight invasion on dogs. About two hours after the operation, no abnormal findings were observed clinically or physiologically. This method was considered to be one of the best for study of the metabolism of chemical substances in the extra-hepatic organs of dogs. The produced ratios of F-TCE, TCA and T-TCE in extrahepatic organs were about 60, 10 and 30% exposure to trichloroethylene at 700 ppm, respectively.

Determination of twist and handedness of a 39-base pair segment of DNA in solution

For DNA in solution, there have been two methods for measuring the helical periodicity. One method examines the ladder of discrete bands formed in the electrophoretic pattern of supercoiled DNA. Such a ladder is assumed to reflect the set of differently linked covalently closed molecules. The other method measures the lengths of partial nuclease digestions of DNA segments affixed to flat surfaces. Neither method, however, is able to measure the absolute handedness. X-ray diffraction of DNA oligonucleotides can determine the handedness, but the DNA must necessarily be crystallized. We have developed a new method for determining the helical parameters of a segment of DNA in solution. It is the first non-crystallographic method that can directly determine both the helical periodicity and the absolute handedness of DNA. The results obtained using this method are consistent with the classical Watson-Crick right-handed double helical model.

[Clinical studies of long acting amoxicillin in oral surgery]

Clinical studies with long acting amoxicillin (L-AMPC) have been carried out and the following results were obtained. 1. Forty-two patients with acute bacterial infections in the oral region were administrated orally L-AMPC at a daily dose of 1 gram. The clinical results obtained were classified as excellent in 3 cases, good in 28 cases, and the overall efficacy was 75.6%. 2. The antibacterial activity of AMPC was determined for 66 strains isolated from patients with oral infections. Of the strains tested, Gram positive cocci showed high sensitivity with MIC's less than 1.56 mcg/ml, while the sensitivity of PC resistance strains of S. aureus, K. pneumoniae and P. vulgaris was lower. 3. There was 1 case of transaminase elevation in the laboratory finding. 4. Five patients reported the following side effects, eruption 3, diarrhea 2, nausea 1, anorexia 1 and malaise 1. From the results of the present study, it is considered that L-AMPC is a useful antibiotic in the treatment of acute bacterial infections in oral region.

[Experimental examinations and toxicokinetic analysis of the absorption and excretion of 1,1,1-trichloroethane by the lung]

Of fifteen dogs each five of them inhaled 1,1,1-trichloroethane (1,1,1-TCE) at the levels of 700, 1500 and 2,000 ppm respectively for one hour. Changes in 1,1,1-TCE concentrations in the expired air, arterial blood and venous blood of dogs were measured from the beginning of exposure until one hour after the end of exposure. The results obtained were as follows. 1. Cumulative uptakes of 1,1,1-TCE in one hour exposure were 27.3 mg/kg at 700 ppm, 44.7 mg/kg at 1,500 ppm and 71.2 mg/kg at 2,000 ppm. 2. Excretion ratios of 1,1,1-TCE in one hour after the exposure were 66-71% at all the three levels of exposure. 3. During the exposure, highly significant negative correlation was seen between arterial/venous blood concentration ratio and expired/inspired air concentration ratio. In the post-exposure period, highly significant positive correlations were seen between expired air concentration and venous or arterial blood concentration. 4. The mean ratio of the total absorption value to the total inspired value was 14% at all the three levels of exposure. 5. From these results, the authors examined the multiple regression equations with two independent variables x and z which are shown as follows. a) During the exposure period, Y1: Cumulative absorption solvent value by the dog (mg/kg) X1: Time of exposure (min) Z1: Level of the solvent value in the ambient air (microgram/ml) log Y1 = -0.526 + 0.622 log X1 + 0.905 log Z1 b) Post exposure period, Y2: Cumulative excreted solvent value by the dog (mg/kg) X2: Time after the end of exposure (min) Z2: Cumulative absorbed solvent value by the dog at the end of exposure (mg/kg) log Y2 = -2.300 + 0.609 log X2 + 0.858 log Z2 We assumed that both equations are very fit and significant.

Experimental myocarditis. II. Cardiac lesions in rats induced by immunization with heterologous heart extracts

The production of myocardial lesions and circulating anti-heart antibodies has been studied in the present experiment. Twenty-one of Wistar rats were divided into 3 groups: 9 rats immunized with heterologous heart extracts, Freund's complete adjuvant and diphtheria-tetanus-pertussis (DTP) vaccine, 8 rats injected phosphate buffered saline adjuvant mixture with DTP vaccine and 4 rats untreated as control. Injection of heterologous heart extracts emulsified with Freund's complete adjuvant and DTP vaccine developed focal myocardial lesions in all of the subjected rats. The lesions were characterized by focal and diffuse interstitial cellular infiltration with myocardial necrosis. The circulating antibodies reacted to rat heart extracts were detected in 77.8% of the subjects. The antigen, reacted with the antibodies, located intracellular spaces in myocardium. The severity of cardiac lesions were not functional to the titer of circulating anti-heart antibodies may play little role in the pathogenesis of myocardial damage at least in this experimental myocarditis.

[Diminution of 1, 1, 1- and 1, 1, 2- trichloroethane in the blood and their excretion by the lungs (author's transl)]

In order to investigate the diminution of 1, 1, 1-trichloroethane (1, 1, 1-TCE) and 1, 1, 2-trichloroethane (1, 1, 2-TCE) in the blood and the excretion of them by the lungs, 100 mg and 50 mg per kg body weight of 1, 1, 1-TCE were intravenously administered to 12 and 13 dogs, respectively, and the same amounts of 1, 1, 2-TCE to 5 and 8 dogs, respectively. The arterial blood gathered and the expired air collected by the time up to 60 minutes after the injection were analysed with a FID-gas-chromatography for the concentrations of the solvents. The results obtained are as follows. 1. Concentrations of 1, 1, 1-TCE in the blood were maintained significantly lower always from 2 to 60 minutes after the injection than those of 1, 1, 2-TCE. 2. While highest concentrations of the solvents in the expired air were found about 1 minute after the injection for both 1, 1, 1-and 1, 1, 2-TCE, values 1 minute after for the former were seven to ten times higher than those for the latter. However, no significant differences in the concentration were seen between both solvents after 15-40 minutes of administration in the expired air. 3. Ratios of the amounts expired by the lungs during 60 minutes after the injection to the total were 61-68% for 1, 1, 1-TCE, whereas only 21-32% for 1, 1, 2-TCE, respectively. 4. Highly significant linear regression was found between the concentrations of the solvent in the blood and those in the expired air for each of 1, 1, 1- and 1, 1, 2-TCE.

Experimental myocarditis. I. Cardiac lesions in rats induced by immunization with homologous heart extracts

The production of myocardial lesions and circulating anti-heart antibodies has been studied in rats injected with homologous heart extracts emulsified with the Freund's complete adjuvant and the DTP vaccine. Six of 7 rats showed lesions of focal myocarditis, while only in one of them circulating anti-heart antibodies were detected. There was no correlation between the presence of circulating anti-heart antibodies and that of myocardial lesions. These findings suggested that the circulating anti-heart antibodies may play little or no role in the pathogenesis of this experimental myocarditis.

Analysis of the heart antigens. Homologous and heterologous anti-heart antibodies and analysis of the heart specific antigens

The present study has indicated the presence of 3 heart specific antigens, using homologous and heterologous antibodies produced in immunized rabbits. Two of these antigenic proteins exhibit restricted organ specificity for heart and the other one shares by heart and kidney. One of these 2 heart specific antigens reacts to both homologous and heterologous anti-heart sera absorbed with kidney, while the other reacts to only heterologous anti-heart sera. The former has an electrophoretic mobility corresponding to that of serum beta-globulin, and is found to have a molecular weight of about 175,000. The latter has the same electrophoretic mobility as that of alpha2-globulin and is found to have a molecular weight of about 50,000.

Quantitative determination of serum immunoglobulins in chronic obstructive pulmonary diseases with special reference to cor pulmonale

In patients with chronic obstructive pulmonary disease, quantitative analysis of serum IgG, IgA and IgM were carried out by use of the radial immunodiffusion method. The concentration of IgE in sera was also determined by the radioactive radial immunodiffusion method. The mean value of serum IgG level in the group of cor pulmonale was higher than that in groups of emphysema, asthma and normal subjects. The mean value of serum IgA level was higher in two groups of cor pulmonale and emphysema than in the group of asthma and of normal subjects. There was no difference of serum IgM levels between these four groups. The mean value of serum IgE in the group of allergic asthma was higher than that in the group of non-allergic asthma or normal subjects and an elevated serum IgE level was also found in patients with cor pulmonale. Findings of this study suggested that the raised level of serum IgG in patients with chronic cor pulmonale might reflect production of antiheart antibodies against cardiac tissue.