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Biomedical subjects

A Okayama

Publications and source records attributed to A Okayama.

At least 127 records · Page 7Linked to original sources
PubMed1990

Antibody profile of early HTLV-I infection.

To define the antibody profile of early seroconversion in infection with human T-cell lymphotropic virus type I (HTLV-I), consecutive serum samples from 10 subjects presumed to have seroconverted on the basis of the particle agglutination test were studied by three enzyme immunoassays and two confirmatory tests (radioimmunoprecipitation and western blot). 3 samples positive and 1 sample indeterminate in the confirmatory tests were reactive in one enzyme immunoassay, which used recombinant envelope antigen, but not in the other two enzyme immunoassays. 2 of 38 particle-agglutination-negative samples had a prozone effect. The confirmatory tests identified 8 seroconverters (7 women, 1 man); their serum samples were used to study the antibody reactivity by western blot assays to HTLV-I specific antigens (three recombinant proteins spanning the N-terminal, middle, and C-terminal env glycoprotein gp46; a recombinant transmembrane protein gp21; a recombinant tax protein; and three gag proteins [p28, p24, and p19]). All 8 seroconverters had antibody reactivities to the C-terminal region (aminoacid residues 229-308) of gp46 and to gag p19 and p24 when their seroconversion was detected.

Adult↗
PubMed1990

Biological monitoring for workers exposed to 4,4'-methylenebis(2-chloroaniline).

Absorption of 4,4'-methylenebis (2-chloroaniline) (MBOCA) was assessed for five workers over one week in a polyurethane elastomer factory by measuring urinary MBOCA levels by high performance liquid chromatography (HPLC) using an electrochemical detector. Personal air exposure levels of MBOCA ranged from 0.2 to 8.9 micrograms/m3. The mean urinary MBOCA levels at the beginning and the end of the work shift were 3.1-81.5 and 2.4-96.6 micrograms/g creatinine, respectively. The differences between preshift and postshift urinary MBOCA values were not significant in all workers, according to the paired t-test. The urinary levels after a two-day holiday (on Monday morning) were almost equal to those of preshift levels on other weekdays. Urinary excretion of MBOCA was much higher than the estimated MBOCA levels from personal exposure measurements, suggesting that a significant amount of MBOCA is absorbed by routes other than inhalation. These results lend strong support for the need to monitor exposure control by urinary MBOCA measurement.

Air Pollutants, Occupational↗
PubMed1990

[Seroepidemiological analysis of the age specific prevalence of anti HTLV-I in Miyazaki Prefecture].

Antibody for HTLV-I in sera from 11,224 residents in Miyazaki Prefecture, Japan, was determined by indirect immunofluorescent antibody method to compare age- and sex-specific antibody prevalence among three geographically divided areas of the prefecture. There was a significant difference in the positive rate of older age groups among three areas, 9.0% for the northern part, 14.5% for the southern part and 8.4% for Miyazaki City, in spite of little variation in younger age groups. A marked rise of positive rate in the southern part at the age of 40th was observed, which suggests that changes of some conditions for mother-to-child transmission happened in the time of their birth. Six seroconversions were observed by the follow-up study for five years of the 971 residents. They were between 28 and 38 years of age, four men and two women. This may provide another reason for the increase in antibody positive rate by age in the adult. However, it could not be investigated if the seroconversion was caused by a horizontal transmission from their spouse. The possibility of the long latency of the virus in man as in the experimental animal may also have to be considered.

Adolescent↗
PubMed1990

[Infections in hematological malignancies--clinical analysis of septic patients admitted to the Second Department of Miyazaki Medical College Hospital in the past ten years].

Two hundred and sixty-two patients (actual number 162) of hematological malignancies were admitted to our department from November 1977 to December 1986. Fourty-three of them (16.4%) were demonstrated to be accompanied with sepsis by blood culture. In acute non-lymphocytic leukemias (AML, APL, AMoL) the rate of sepsis was 33.8% (27 patients), while in lymphocytic malignancies (ML, HD, ATL) it was 11.7% (16 patients), particularly being 3.0% in ATL. Among the detected pathogenic microorganisms, gram-negative bacilli were 86.2% in the former and 50.0% in the latter. Especially, Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli occupied 58.6% of the total in the former. Laboratory examination, when sepsis occurred, revealed peripheral neutropenia in acute non-lymphocytic leukemias (mean 831/cmm) but not in lymphocytic malignancy (mean 4,420/cmm). And 20 of the 27 cases showed remarkable neutropenia of below 500/cmm in the former. On the other hand in the latter, out of 16 only one with ATL was the case. Hypogammaglobulinemia was one of the characteristic features in lymphocytic malignancies but not in acute non-lymphocytic leukemias. Hypogammaglobulinemia in lymphocytic malignancies might be affected by long-term immunodepressant therapy. Immunologic skin reaction was demonstrated to be decreased in lymphocytic malignancies on admission. From the findings mentioned above, affecting factors to infections may be mainly neutropenia in acute non-lymphocytic leukemias and immunodeficiency in lymphocytic malignancies. And sepsis can occur frequently under neutropenic condition. In ATL both of humoral- and cellular-immunologic disturbance were detected before therapy. But peripheral neutrophil count was maintained to be normal and this could be the reason for the low septic incidence in ATL despite of total immunodepression.

Agammaglobulinemia↗
PubMed1990

Optimized fluorometric determination of urinary delta-aminolevulinic acid by using pre-column derivatization, and identification of the derivative.

We previously reported the usefulness of a fluorometric method to determine urinary delta-aminolevulinic acid (ALA) concentrations by using post-column derivatization to monitor the effect of lead exposure. We have further improved the method by introducing pre-column derivatization by using reaction of ALA with acetylacetone and formaldehyde. Response of the hematopoietic system to lead exposure can now be easily detected at blood lead concentrations as low as 162 micrograms/L. The fluorescent ALA derivative, a new aromatic product, 2-methylideneamino-3,5-diacetyl-4,6-dimethylphenylpropionic acid, is separated on octadecyl silica column by high-performance liquid chromatography and the fluorescence intensity is detected with a fluorophotometer. Sample recoveries for 12 urine samples from workers exposed to lead and unexposed controls were 91.9-110.2%. The results obtained by the pre-column derivatization method agreed with those by the post-column derivatization method. The new method increases the sensitivity to a detection limit to 10 micrograms of delta-aminolevulinic acid per milliliter of urine and is simple enough to be used for routine monitoring of the biological effect of exposure to low concentrations of lead.

Aminolevulinic Acid↗
PubMed1990

Suppression of delayed-type hypersensitivity to PPD and PHA in elderly HTLV-I carriers.

In a previous study on immune responsiveness among asymptomatic human T-cell leukemia virus type I (HTLV-I) carriers, we found that carriers had significantly reduced delayed-type hypersensitivity (DTH) response to purified protein derivative (PPD) skin testing. The association was strongest among persons at least 60 years of age. In order to evaluate this finding further, we evaluated the response to both PPD and phytohemagglutinin (PHA) in an elderly population. Fifty-six consecutive hospitalized patients with nonimmunosuppressive diseases were examined. None had a history of tuberculosis nor evidence of the known HTLV-I-associated diseases. The subjects' ages ranged from 62-93 years (median = 75 years); 43 were women and 13 were men. Twenty-two of the subjects were HTLV-I antibody positive. Among the carriers, there was an increased level of nonreactivity to PPD, the relative risk adjusted for age (RR) being 1.9 (95% confidence interval, 0.62-5.8), as well as to PHA of RR = 2.3 (0.60-9.0). When subjects were cross-classified for response to both skin tests, 15 of 17 carriers were nonreactive to either or both antigens compared to 15 of 25 noncarriers [RR = 5.1 (0.99-25.9) (p value, one-sided = 0.026)]. The decline in reactivity to both antigens increased with age, but was consistently lower among the carriers. Among subjects with positive reactions to PPD, the degree of reaction as measured by the size of erythema was reduced among the carriers; however, for PHA responders, the response in carriers appeared to be normal. Among the HTLV-I antibody negative subjects, the size of erythema for both antigens was strongly correlated (p = 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

A new HPLC fluorimetric method to monitor urinary delta-aminolevulinic acid (ALA-U) levels in workers exposed to lead.

A new sensitive HPLC method for the determination of urinary delta-aminolevulinic acid (ALA-U) was used to evaluate the relationship between blood-lead (Pb-B) and ALA-U levels in male workers exposed to lead. The differences between the ALA-U levels determined by this method (ALA-U-HP) and by a colorimetric method (ALA-U-CL) are discussed. The HPLC method gave values similar to the ALA-U-CL values at high ALA-U level. However, at low blood-lead levels (58 +/- 22 micrograms/l, n = 23), the mean ALA-U-HP level corrected by urinary creatinine level was one-third of the corrected ALA-U-CL level (0.83 +/- 0.14 and 2.4 +/- 0.5 mg/g creatinine, respectively). A significant increase of the mean corrected ALA-U-HP level was observed at 162 +/- 22 micrograms/l Pb-B (P less than 0.05, n = 26), while that of ALA-U-CL was observed at 245 +/- 30 micrograms/l Pb-B (P less than 0.01, n = 37). The regression equation based on the logistic model fitted well to the relationship data between the Pb-B level and the percentage of the subjects with corrected ALA-U-HP above the cut-off point (1.12 mg/g creatinine) and the expected Pb-B level for 50% response was 270 micrograms/l Pb-B, while it did not fit well to the relationship data between Pb-B level and the percentage of the subjects with corrected ALA-U-CL above the cut-off point (3.5 mg/g creatinine).(ABSTRACT TRUNCATED AT 250 WORDS)

Aminolevulinic Acid↗
PubMed1989

[A study on immunity in tsutsugamushi disease].

The immune response in human tsutsugamushi disease (scrub typhus) was studied. Anti-rickettsial activity of sera, peripheral mononuclear cells and their culture supernatants from patients on in vitro growth of Rickettsia tsutsugamushi proliferating in normal human peripheral macrophages was examined. The results obtained were as follows. 1) Sera from patients at the early convalescent stage, which exhibited high antibody titers against R. tsutsugamushi, effectively inhibited their growth in macrophages. 2) Sera from patients after a long period from the onset showed low antibody titers and did not inhibit rickettsial growth. 3) Mononuclear cells and T cell enriched fractions suppressed rickettsial growth when they were obtained from the patients at the early convalescent stage and even after as long as 3.5 years from the onset. 4) The culture supernatants of the T cell-enriched fractions which were collected from the patients mentioned above, exhibited a similar antirickettsial activity. These findings indicate that sensitized T lymphocytes and macrophages might play a fundamental role in immunological defense mechanism in tsutsugamushi disease. And the results obtained in our experiments are compatible with those previously reported in experimental scrub typhus in laboratory animals such as mice and monkeys.

Adult↗
PubMed1989

Antibody reactivity to different regions of human T-cell leukemia virus type 1 gp61 in infected people.

The primary protein product of the human T-cell leukemia virus type 1 (HTLV-1) env gene, gp61, is cleaved to produce both the exterior (gp46) and the transmembrane (gp21) portions of the HTLV-1 envelope protein. To compare the reactivity with human antibodies of different regions of this gp61 protein, five plasmids (A, B, B1, C, and D) were constructed to express recombinant proteins (RPs) in Escherichia coli. RP-A, RP-B, RP-B1, and RP-C contain amino acid residues 26 to 165, 166 to 229, 166 to 201, and 229 to 308, respectively, of the exterior envelope protein gp46. Serum samples from HTLV-1-seropositive subjects were assayed for reactivity with these RPs by Western immunoblotting. The percentages of positive reactivity with each of the RPs were as follows: 18.9% (23 of 122) for RP-A, 89.6% (112 of 125) for RP-B, 70.2% (85 of 121) for RP-B1, and 92.9% (117 of 126) for RP-C. These results indicate that the C-terminal half of gp46 (RP-B plus RP-C) can detect 97.6% (123 of 126) of positive samples, while the N-terminal half of gp46 (RP-A) can only detect 18.9% of the HTLV-1-positive sera (P less than 0.005). Furthermore, RP-A, -B, and -C, which together span the entire length of gp46 except the first five amino acids at the N terminus and the last four amino acids at the C- terminus, detected 99.2% (125 of 126) of the HTLV-1-positive subjects. In contrast, RP-D, which contains the HTLV-1 transmembrane envelope protein gp21 minus the first amino acid at the N terminus, had a lower rate of antibody reactivity at 73.7% (84 of 114) (P less than 0.005). The difference in seropositive rates for RP-D between HTLV-1 carriers (55.6%) and adult T-cell leukemia patients (85.5%) is statistically significant (P less than 0.01). This study therefore indicates that the C-terminal half of gp46, especially the amino acid sequence from 200 to 308, contains the most reactive epitopes of the HTLV-1 gp61 envelope glycoprotein.

Antigen-Antibody Reactions↗
PubMed1989

Sagittal tomography in the supine patient.

The authors have developed a multidirectional tomographic unit to obtain sagittal images with the patient in the supine or prone position. The apparatus is particularly useful for examination of the vertebral column and sella turcica. It can be employed in circular (0 degrees -40 degrees) and spiral (10 degrees -32 degrees) motions. The apparatus provides correct and easy positioning of subjects with easy maintenance of posture. It reduces the distortional effects of respiration and thereby markedly improves reproducibility.

Humans↗
PubMed1988

Suppression of tuberculin skin reaction in healthy HTLV-I carriers from Japan.

Although it is thought that infection with human T-lymphotropic virus type I (HTLV-I) is immunosuppressive, this has not been clearly demonstrated among healthy carriers, and there are no data concerning delayed-type hypersensitivity (DTH). To evaluate this hypothesis, DTH to purified protein derivative (PPD) of tuberculin was measured in 126 healthy adults from an endemic area for HTLV-I infection in southern Japan. Among the 39 HTLV-I carriers, only 15% had detectable induration following PPD exposure, compared to 46% of the 87 non-carriers. In addition, the size of erythema among those carriers with a positive reaction was about 70% of that among non-carriers. Overall, there was a significantly inverse association between the degree of DTH response and prevalence of antibody. In relation to subjects with strong to moderate reaction, those with negative or indefinite reaction were 6 times more likely to be a carrier. This association was much stronger among subjects aged 60 years or older than among younger persons. These findings indicate that there is subclinical immunosuppression among HTLV-I carriers, which increases with age.

Adult↗
PubMed1988

Enzymatic studies on tryptophan metabolism disorder in rats chronically exposed to carbon disulfide.

Eight-week-old female Wistar rats were exposed to carbon disulfide for 6 hr a day, 5 days a week, for 12 weeks in inhalation chambers. Then the activities of the main enzymes of tryptophan metabolism (i.e., L-tryptophan 2,3-dioxygenase, indoleamine 2,3-dioxygenase, kynurenine 3-hydroxylase, kynureninase, and kynurenine aminotransferases) in their tissues were determined. The results showed that exposure to carbon disulfide caused a significant increase in the activities of kynureninase and kynurenine-2-oxoglutarate aminotransferase in the kidneys, but only a slight increase in their activities in the liver. The activities of L-tryptophan 2,3-dioxygenase and kynurenine 3-hydroxylase also tended to increase, but the increases were not statistically significant. These results suggests that the kynurenine pathway of tryptophan metabolism in the kidneys of rats exposed to carbon disulfide is activated and that the increased activities of kynurenine-2-oxoglutarate aminotransferase in the kidneys may cause the increased excretion of tryptophan metabolites after tryptophan loading as shown in an earlier study (A. Okayama, L. Fun, A. Yamatodani, Y. Ogawa, H. Wada, and S. Goto, 1987, Arch. Toxicol. 60, 460-463.

Animals↗
PubMed1988

Comparative diagnostic assay results for detecting antibody to HTLV-I in Japanese blood donor samples: higher positivity rates by particle agglutination assay [corrected].

Higher positivity rates for prevalence of anti-HTLV-I antibody have been reported for the gelatin particle agglutination (PA) assay when compared to that of the indirect immunofluorescence assay using acetone-fixed HTLV-I producing cells (IF-FA). To evaluate the discrepancy between these two screening methods, PA-positive/IF-FA-negative sera were tested by four additional assays for anti-HTLV-I: indirect immunofluorescence assay using live HUT102 cell membranes (IF-MA), enzyme immunoassay (EIA), radioimmunoprecipitation (RIP), and Western blotting (WB). Sera obtained from 6915 Japanese blood donors were assayed for anti-HTLV-I antibody by PA, and 389 (5.6%) were positive. These 389 sera were re-examined by IF-FA, and 29 (7.5%) were negative. Sufficient material was present for 20 of the 29 PA-positive/IF-FA-negative sera for further evaluation by the IF-MA, EIA, RIP, and WB. Fifteen (75%) of the 20 were positive by IF-MA, but only 6 (30%) were positive by EIA. Both RIP and WB confirmed 17 (85%) of the samples, with each detecting a serum that was negative by the other. Thus, 18 (90%) of the 20 were confirmed by either RIP or WB. The nonconfirmed sera were all positive on PA at low titer. These findings suggest that the PA assay is more sensitive than either IF-FA or EIA.

Agglutination Tests↗
PubMed1988

Determination of 4,4'-methylenebis(2-chloroaniline) in urine by liquid chromatography with ion-paired solid-phase extraction and electrochemical detection.

This highly specific and sensitive method for measuring urinary 4,4'-methylenebis(2-chloroaniline) (MBOCA) involves liquid chromatography with electrochemical detection. Before chromatography, urine samples are prepared by ion-paired solid-phase extraction on a disposable octadecylsilica column with acidic methanol solution containing 1-heptanesulfonic acid. This enhances the specificity of the method. Mean overall recovery ranged from 97.1% to 99.5% at added MBOCA concentrations of 20 and 100 micrograms/L in urine. Sensitivity for urine was 1 microgram/L. The intra-assay CV was 2.2% at a MBOCA concentration of 100 micrograms/L. We believe that this method is acceptable for routine measurement of MBOCA in urine from individuals exposed to this industrial chemical.

Benzhydryl Compounds↗
PubMed1988

[Acute myocarditis with localized left ventricular aneurysm: a report of three cases].

Ventricular aneurysms are rarely observed in viral myocarditis. Three cases whose left ventriculograms showed localized left ventricular aneurysms in the chronic phase of myocarditis are reported. The etiology in one case was herpes simplex virus (Case 1). Two cases (Case 2, 3) of myocarditis were admitted to our Coronary Care Unit in the acute phase, when diffuse hypokinesis of the left ventricle was demonstrated by two-dimensional (2-D) echocardiography. Hypokineses progressed to localized left ventricular aneurysm formation, demonstrated by cine angiography. In the acute phase, ST segment elevation was observed in these two cases, but it resolved. Abnormal Q waves also resolved in the chronic phase. Negative T waves were nearly normalized in one of them (Case 3). Abnormal Q waves with ST segment depression were observed in another case (Case 1). Thus, there were no characteristic or consistent findings suggesting a left ventricular aneurysm on electrocardiography. 2-D echocardiography and cine angiography proved useful for diagnosing this uncommon complication. Long-term follow-up of these cases will be important, because viral myocarditis can develop into dilated cardiomyopathy. The mechanism of left ventricular aneurysm following acute viral myocarditis included: (1) direct viral injury of the myocardium, (2) localized injury due to immunological mechanisms, and (3) coronary thrombosis due to increased platelet aggregation by viral infection.

Acute Disease↗
PubMed1987

Effect of exposure to carbon disulfide on tryptophan metabolism and the tissue vitamin B6 contents of rats.

Female Wistar rats were exposed to 100 ppm or 600 ppm carbon disulfide for 6 hours a day, 5 days a week for 12 weeks. During the exposure period, their urinary excretion of 4-pyridoxic acid was determined. The urinary excretions of xanthurenic acid and kynurenic acid after tryptophan loading were also determined. At the end of the exposure period, the rats were sacrificed and the levels of the five major forms of vitamin B6, pyridoxine, pyridoxal, pyridoxamine, pyridoxal phosphate and pyridoxamine phosphate, in the liver, kidneys and brain were determined by HPLC fluorometry. During the exposure the urinary excretions of xanthurenic acid and kynurenic acid after i.p. administration of tryptophan increased significantly in both experimental groups. However, urinary excretion of 4-pyridoxic acid decreased only slightly in the group exposed to carbon disulfide at 600 ppm and did not decrease in the group exposed to 100 ppm carbon disulfide. Furthermore, no significant changes were observed in the contents of vitamins B6 in any tissues examined. These results indicate that carbon disulfide does not cause vitamin B6 deficiency and thus that the disorders of tryptophan metabolism induced by carbon disulfide intoxication are not due to vitamin B6 deficiency.

Animals↗