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H Kito

Publications and source records attributed to H Kito.

At least 55 records · Page 3Linked to original sources
PubMed1992

Generation of mutagenicity by ozonation of humic substances' components.

Components of humic substances, such as vanillin, syringaldehyde, vanillic acid and di-n-butylphtalate, were ozonated and subjected to the mutagenicity assay using Salmonella typhimurium TA 98 and 100 with and without S9 mix. The strong mutagenic activity was found on all components except di-n-butylphtalate by strain TA 100 with and without S9 mix. Substances with strong mutagenic activity in ozonated vanillin were water-soluble and were slightly extracted with benzene, dichloromethane and ethyl acetate. Following gel chromatography on Sephadex G-10, the strong mutagens generated by ozonation were found with molecular weights greater than 300.

Animals↗
PubMed1992

Does juxtamesenteric placement of intra-aortic balloon interrupt superior mesenteric flow?

To assess influences of intra-aortic balloon pumping (IABP) on superior mesenteric flow, 15 postoperative patients were examined, in whom distal aspects of balloons were distal to the superior mesenteric artery. Superior mesenteric flow velocity-time integral in systole (IntS), that in diastole (IntD), and the sum of IntS and IntD (IntS+IntD) were determined on and off IABP (IABP ON-OFF test). The same parameters were obtained with balloon inflating on every other beat (IABP 1:2 test). The cardiac cycle with balloon inflation during diastole was defined as "1:2 ON," and the cardiac cycle without balloon inflation during diastole was defined as "1:2 OFF." (1) IABP ON-OFF test. IABP increased IntS (p less than 0.01), IntD (p less than 0.01), IntS+IntD (p less than 0.01), and cardiac output (p less than 0.05). The increments in IntS, IntD and IntS+IntD on IABP are attributed largely to an increased in cardiac output. (2) IABP 1:2 test. IntS during 1:2 OFF was greater than IntS during 1:2 ON (p less than 0.01), whereas IntD during 1:2 OFF was smaller than IntD during 1:2 ON (p less than 0.01). There was no significant difference in IntS+IntD between 1:2 ON and 1:2 OFF. These data suggest that juxtamesenteric balloon placement did not interrupt the arterial inflow of a superior mesenteric artery.

Blood Flow Velocity↗
PubMed1992

Doppler echocardiographic measurement of cardiac output in man using mitral annulus method.

The mitral inflow method of measuring cardiac output with pulsed Doppler two-dimensional echocardiography was developed and validated against the thermodilution technique in 42 patients. A mitral inflow method combined the velocity of left ventricular inflow at the mitral annulus (apical long-axis view) with the cross-sectional area of the annulus calculated from its diameter (parasternal long-axis view). A good correlation was observed between thermodilution and Doppler measurements of cardiac output (r = 0.93). The ratio of Doppler measurements to thermodilution measurements will be between 0.76 and 1.15 for about 95% of cases. There was a good correlation between percentage change in thermal cardiac output and those in Doppler cardiac output (r = 0.95); the limits of agreement were -11.5% to 10.5%, suggesting that this method can be most useful for assessing relative changes in cardiac output.

Blood Flow Velocity↗
PubMed1992

Effects of intraaortic balloon pumping on mitral flow dynamics in patients with coronary artery bypass operations.

We evaluated the improvement in left ventricular function in 26 patients after coronary artery bypass grafting who were treated with intraaortic balloon pumping (IABP). Mitral flow velocity-time integral in the rapid filling phase (IntR) and that in the atrial contraction phase (IntA), the sum of IntR and IntA (IntR+IntA), and the ratio of IntA to IntR (IntA/IntR) were calculated with patients on and off balloon pumping (IABP ON-OFF test). IABP increased IntR and IntR+IntA, decreased IntA/IntR, and did not change IntA, suggesting that a decreased afterload or augmented coronary perfusion improves left ventricular relaxation. When the balloon inflated on every other beat (IABP 1:2 test), IntR and IntR+IntA increased without balloon assist, IntA/IntR decreased off IABP, and IntA did not change. The afterload reduction or augmented coronary perfusion on the previous beat with IABP might help ventricular filling on the next beat without balloon assist. A drastic decrease in IntR after IABP stopped indicated the need to continue IABP. Since the change in IntR during IABP ON-OFF test was significantly correlated with that in IntR during IABP 1:2 test, the change in IntR during IABP 1:2 test could help to predict the optimal time of weaning.

Aged↗
PubMed1992

Modulating effect of tanshinones on mutagenic activity of Trp-P-1 and benzo[a]pyrene in Salmonella typhimurium.

The modulating effects of the Chinese medicinal plant 'Tan-shen', the radix of Salvia miltiorrhiza Bunge, on the mutagenic activities of Trp-P-1 (3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole) and B(a)P (benzo[a]pyrene) were investigated using Salmonella typhimurium TA98. Ether- and hot water-extracted 'Tan-shen' enhanced both mutagens at low concentrations, but suppressed them at high concentrations. Extracts by ether treatment were more effective than those extracted by hot water. Dihydrotanshinone I, cryptotanshinone, tanshinone I, and tanshinone IIA were isolated from the ether extract by high performance liquid chromatography (HPLC) and were recognized to be the mutagenic modulators. 4 tanshinones enhanced the mutagenicity of Trp-P-1 by 8-24-fold at 20 micrograms/plate and the enhancement was reduced at the higher concentration. Dihydrotanshinone I suppressed Trp-P-1 activity completely at 100 micrograms/plate.

Abietanes↗
PubMed1992

Aldehydes as mutagens formed by ozonation of humic substances.

Humic substances and p-hydroxybenzaldehyde, one of their components, were ozonated and quantitative analysis of the mutagenic aldehydes (formaldehyde, acetaldehyde, glyoxal, glyoxylic acid and methylglyoxal) was performed. Glyoxal and glyoxylic acid were the main mutagenic compounds. The ozone-treated solutions were flowed through a granular activated carbon (GAC) column and the KMnO4 consumed of the effluent decreased to about 40-50%. Most of the aldehydes formed by ozonation reduced, but glyoxal increased.

Acetaldehyde↗
PubMed1992

The genotoxicity of organotin compounds in SOS chromotest and rec-assay.

In these days pollution by organotin compounds in the environment extends widely and effects on human health are feared. We studied the genotoxicity of various organotin compounds (butyltins, phenyltins, methyltins) and inorganic tin (SnCl4), which are present in the environment, with the SOS chromotest and the rec-assay. Mono-n-butyltin oxide, n-butyltin trichloride and di-n-butyltin dichloride showed high SOS-inducing potency in the SOS chromotest with Escherichia coli PQ37. Di-n-butyltin dichloride, tri-n-butyltin chloride, bis(tri-n-butyltin)oxide, dimethyltin dichloride and trimethyltin chloride were recognized as genotoxic chemicals by the rec-assay.

4-Nitroquinoline-1-oxide↗
PubMed1992

Transoesophageal Doppler echocardiographic measurement of cardiac output by the mitral annulus method.

OBJECTIVE: To compare cardiac output measured by the transoesophageal Doppler and thermodilution techniques. DESIGN: Prospective direct comparison of paired measurements by both techniques in each patient. SETTING: Intensive care unit in a cardiovascular centre. PATIENTS: 65 patients after open heart surgery (mean (SD) age 53 (12) years). INTERVENTIONS: Cardiac output was measured simultaneously by the transoesophageal Doppler and thermodilution techniques. Cardiac output was measured again after a mechanical intervention or volume loading. RESULTS: The limits of agreement were -2.53 to +0.83 1.min-1 for cardiac output measured by the Doppler and thermodilution techniques. This suggests that the Doppler method alone would not be suitable for clinical use. The second measurement of cardiac output by thermodilution was compared with cardiac output estimated from the first and second Doppler measurements and the first thermodilution measurement. The limits of agreement (-0.55 to +0.51 1.min-1) were good enough for clinical use. CONCLUSIONS: After cardiac output had been measured simultaneously by both the Doppler and thermodilution techniques, subsequent transoesophageal Doppler alone gave a clinically useful measurement of cardiac output.

Adult↗
PubMed1992

[Validation of Doppler arterial flow in humans].

A method of measuring volumetric flow in human arteries with pulsed Doppler technique was developed. Doppler flowmetry was assessed in 11 adult patients whose admission-diagnoses included aneurysm of the aorta or dissections. During surgery, regional blood flows of the left common carotid artery, terminal aorta, common iliac artery, external iliac artery or common femoral artery were measured by Doppler method and electromagnetic flowmeter. Eighty four arterial flow determinations were obtained from the 11 patients studied. On comparison of simultaneous electromagnetic and Doppler measurements of blood flow, an excellent correlation (r = 0.93) was found between the two methods. The slope of the regression line was 0.587. Regional blood flow was measured with Doppler flowmetry in another 9 patients. The values of the left common carotid, celiac, superior mesenteric and terminal aortic flows were 251 +/- 62, 608 +/- 399, 687 +/- 381, 783 +/- 324 ml.min-1, respectively. This method provides an easy, reliable way of measuring regional blood flow.

Aged↗
PubMed1991

Mutagenicity of the components of ozonated humic substance.

Eight components of humic substances were ozonated. Mutagenic activity was found with TA100 with and without S9 mix for all ozonated components. Ozonated products of p-hydroxybenzaldehyde were separated into five fractions by silica gel chromatography and each fraction subjected to mutagenicity assay. Mutagenic activity was found in the chloroform and chloroform-acetone (1:1) fractions. The compounds in these fractions were identified, and aldehydes such as formaldehyde, acetaldehyde, glyoxal, glyoxylic acid and methyl glyoxal were found to be mutagenic. Mutagenic compounds are present in the polar fraction.

Aldehydes↗
PubMed1991

Mutagenicity of ozonation and chlorination products from p-hydroxybenzaldehyde.

p-Hydroxybenzaldehyde, a component of soil humic substances, was ozonated and chlorinated. The ether extract and the residue were subjected to the Ames assay; mutagenic activities were identified. The non-ionic resin CSP800 and the anion exchange resin CHPA25 were used for separation of mutagenic compounds. The compounds in the water layer were not adsorbed on CSP800 or CHPA25 and exhibited strong mutagenic activity. Mutagenic activity was reduced as the added chlorine was increased. Ether extracts were analyzed by gas chromatography-mass spectrometry (GC-MS) and chloral, 1,3-dichloro-2-propanone, 1,2,3-trichloro-1-propene, tetrachloroethylene and 1,1,1,3,3-pentachloro-2-propanone were identified as mutagenic compounds.

Animals↗
PubMed1991

Dose-response relationship between dietary cadmium intake and metallothioneinuria in a population from a cadmium-polluted area of Japan.

An epidemiological study to examine the dose-response relationship for environmental cadmium exposure was performed in 1843 cadmium-exposed and 240 non-exposed inhabitants of the Kakehashi River basin in Ishikawa, Japan. The average cadmium concentration in rice from each village was employed as an indicator of cadmium exposure and the individuals were grouped according to the length of residence in the polluted area. Metallothioneinuria was used as an index of renal tubular dysfunction produced by the chronic exposure to cadmium. A dose-related increase in metallothioneinuria was observed. The chronic total cadmium intake resulting in metallothioneinuria in this population was calculated to be approximately 2 g for both men and women. The cumulative lifetime dose of 2 g cadmium over a 50-year period, means an average daily intake of 110 micrograms. Thus, these values may be regarded as the maximum allowable lifetime and daily intake limits, respectively for chronic dietary exposure to cadmium.

Administration, Oral↗
PubMed1991

Evaluation of the SOS chromotest for the detection of antimutagens.

The SOS chromotest was applied for the detection of antimutagens. To raise SOS induction, the bacteria were treated with the mutagens, UV, 4-nitroquinoline N-oxide (4NQO), N-methyl-N'-nitro-N-nitroso-guanidine (MNNG), or benzo[a]pyrene (B[a]p). The inhibitory effects of L-ascorbic acid, glutathione, vanillin, 5-fluorouracil (5-FU), 5-chlorouracil (5-CU), cobaltous chloride, sodium selenite and sodium arsenite, which are known as antimutagens, were investigated with their addition either simultaneously or post treatment time. It became clear that the SOS chromotest was very useful for the detection of antimutagens.

Ascorbic Acid↗
PubMed1991

Dose-response relationship between urinary cadmium and metallothionein in a Japanese population environmentally exposed to cadmium.

The dose-response relationship between cadmium (Cd) exposure and renal dysfunction, as measured by urinary Cd and metallothoinein (MT), was evaluated in a population living in the Kakehashi River basin, a Cd-polluted area in Japan. Morning urine specimens were collected from 1397 men and 1713 women who were 50 years or older. In addition, urine specimens were collected from a control population consisting of 110 men and 130 women. The 97.5% upper limits for MT in the control population were used to determine the prevalence rates for MT-uria at various urinary Cd concentrations. Probit linear regression analysis showed significant dose-response relationships between MT and Cd. In the control population, prevalence rates of MT-uria for men and women were 1.8 and 3.1%, respectively. Based on the prevalence rates of MT-uria in the control population, the upper limits for the urinary Cd concentrations were calculated from the slopes of the regression lines to be 4.2 and 4.8 micrograms/g creatinine for men and women, respectively. These values, which are similar to those reported previously using urinary beta 2-microglobulin as the indicator, may be of use in establishing the biological threshold, i.e. maximum allowable concentration, for urinary Cd in the environmentally exposed Japanese population.

Age Factors↗
PubMed1991

Detection of viral DNA in neonatal herpes simplex virus infections: frequent and prolonged presence in serum and cerebrospinal fluid.

Polymerase chain reaction (PCR) assay was used to detect herpes simplex virus (HSV) DNA in mouth, skin, sera, or cerebrospinal fluid (CSF) from seven neonates with HSV infection. In a culture-negative patient, the diagnosis was confirmed by detection of HSV DNA. Serial examinations revealed that HSV DNA remained in the serum and/or CSF from several patients for 1-2 weeks after the beginning of treatment. Next, the results of PCR assay in neonatal HSV infections were compared with those in older children with herpes simplex encephalitis (HSE). HSV DNA was detected in CSF from four neonates with central nervous system involvement and in CSF from all nine children with HSE. Sera were positive for HSV DNA in five of seven neonates, including two cases of localized infections, but in none of the children with HSE. These results suggest that HSV may be spread principally via viremia in neonates. PCR assay could be useful for the confirmative diagnosis of neonatal HSV infections, especially in culture-negative cases.

Base Sequence↗
PubMed1991

[Transesophageal Doppler echocardiographic measurement of cardiac output using mitral anulus method].

The method of measuring cardiac output with transesophageal pulsed Doppler two-dimensional echocardiography was developed and validated by comparison with the thermodilution technique in 65 adult patients. With the use of transesophageal four-chamber view, the Doppler sample volume was placed in the center of the mitral ring and the mitral flow velocity-time integral was obtained through planimetric measurements of the mitral flow velocity curve. The diameter of the mitral valve anulus was measured at the time of peak rapid filling flow velocity, and the cross-sectional area of the mitral valve anulus was calculated, assuming a circular shape. Doppler-determined cardiac output was calculated by using the following formula: Cardiac output [1.min-1] = pi (D [cm] /2)2.MFVI [cm].heart rate [bpm].10(-3), where MFVI is mitral flow velocity-time integral, and D is the diameter of the mitral valve anulus. There was a weak correlation between thermodilution and Doppler measurements of cardiac output (r = 0.64, p less than 0.01), while a good correlation was observed between percent changes in thermodilution-derived cardiac output and those in Doppler-determined cardiac output (r = 0.92, p less than 0.01) during different loading conditions. It has been suggested that this method may be useful for assessing relative changes in cardiac output during short time periods.

Adult↗
PubMed1991

[Influences of intra-aortic balloon pumping on peripheral hemodynamics].

The influences of intra-aortic balloon pumping (IABP) on peripheral dynamics were assessed by Doppler echocardiography. The subjects were 20 patients requiring IABP support, postoperatively, to control low cardiac output state. The flow velocity integral in systole (Int S) and that in diastole (Int D) were measured from left common carotid, superior mesenteric, and terminal aortic flow pattern, and the sum of Int S and Int D (Int S + Int D) was calculated with and without balloon pumping. 1) IABP increased cardiac output significantly (p less than 0.01). 2) Common carotid flow: IABP increased Int S significantly (p less than 0.01), but neither Int S nor Int S + Int D changed significantly with IABP. 3) Superior mesenteric flow: IABP increased Int D significantly (p less than 0.01), but both Int S and Int S + Int D remained unchanged with IABP. 4) Terminal aortic flow: None of Int S, Int D and Int S + Int D changed significantly with IABP. These results suggest that the carotid area can receive much of the increase in cardiac output in systole with IABP, and that the superior mesenteric area can receive much of the volume of blood displaced in the aorta by balloon inflation in diastole.

Aged↗