Search PubMed⌕ Search

Biomedical subjects

S Horiguchi

Publications and source records attributed to S Horiguchi.

At least 73 records · Page 4Linked to original sources
PubMed1992

[A case of progressive supranuclear palsy presenting mouth opening difficulty with tonic contraction of the orbicularis oris muscle].

A 72-year-old man developed supranuclear ophthalmoplegia, bradykinesia, rigidity, unsteady gait, dementia, dysphagia, retrocollis, grasp reflex and apraxia of eyelid opening. These findings were compatible with progressive supranuclear palsy (PSP). At the age of 66, he presented a peculiar phenomenon characterized by simultaneous tonic contraction of the orbicularis oris muscle (OOM) and the palatal muscles elicited by pronouncing "pa", which resulted in difficulty of voluntary opening of the mouth and the rhinopharynx. Therefore, the respiration air reciprocated between the lung and the closed mouth. The expiratory pressure puffed out the cheeks, while the lips remained tightly closed. While the respiratory movements and the pressure increased by degree, the OOM contracted more strongly in proportion to the pressure. Sixty to ninety seconds after the elicitation, the pressure overcame the contraction of the OOM and the course of the phenomenon was completed. The electromyograms showed that the OOM activity was prolonged after initial voluntary contraction, remaining thus after a tracheostomy for pneumonia at the age of 72, and that it increased in response to the pressure. Apraxia of eyelid opening, one of the other symptoms, resembled this phenomenon in terms of the aspect of difficulty of voluntary mouth opening. The "holding" phase of grasp reflex, yet another symptom, resembled it in the recruitment of the OOM activity. The phenomenon is not common in patients with PSP. However, we concluded that it may be included among the symptoms of PSP because it has similar characteristics to apraxia of eyelid opening and grasp reflex, which are not uncommon in patients with PSP.

Aged↗
PubMed1992

[The inhibitory effects of platelet activating factor (PAF) on ciliary activity of human paranasal sinus mucosa].

The effect of platelet activating factor (PAF) on human paranasal ciliated cells was investigated in vitro. Normal human paranasal sinus mucosa was obtained by surgical procedure and incubated with Eagle's MEM containing 10% FCS in the form of tissue culture. Ciliary activity was viewed at 37 degrees C under an inverted microscope equipped with a thermoregulator and a humidified CO2 chamber, recorded on video tapes and photoelectrically measured. Ciliary inhibition was observed by the treatment with PAF, in a dose dependent manner, at concentrations from 10(-10) M to 10(-6) M. The inhibitory effect of 10(-8) M PAF on ciliary activity was completely blocked when the mucosa was treated with 10(-6) M CV-3988 or 10(-6) M CV-6209 (specific PAF receptor antagonists). By the radioimmunoassay, the concentration of PAF in tissue culture was reduced by half within 12.5 min, and within 60 min it was only 5% of the initial concentration. There was no significant difference in ciliary inhibition between irrigation after a 60 min incubation with 10(-8) M PAF and non-irrigation. These results indicate that PAF inhibited ciliary activity directly and specifically, and induced irreversible damage primarily within the first 60 min after the challenge.

Cilia↗
PubMed1992

Serum immunoglobulin and complement C3 levels in workers exposed to lead.

Serum immunoglobulin and complement C3 levels were measured in workers exposed to lead at a secondary lead refinery and a solder factory. In the first survey, significant correlations were found between blood lead and IgA with a correlation coefficient of 0.296, and between blood lead and IgE with a correlation coefficient of 0.314. No other significant correlations were found among the indicators of lead exposure and humoral immunity. In the second survey, no significant correlations were found between blood lead and IgG and IgA. A significantly higher number of subjects with IgE of more than 400 IU/ml was found in the group with blood lead of more than 60 micrograms/100 g.

Adolescent↗
PubMed1992

[Mechanisms of hypoalgesia induced by intracisternal administration of PGD2 or PGE2].

Intracisternal administration of PGD2 (5 micrograms) and PGE2 (5 micrograms) induced hypoalgesia in conscious mice in acetic acid writhing test. The hypoalgesia caused by PGD2 was blocked by para-chlorophenylalanine, cyproheptadine or phenoxybenzamine. However, the suppression of writhing responses caused by PGE2 was not blocked at all by these drugs. These results indicate that the actions of PGD2 depend upon serotonin and norepinephrine systems.

Animals↗
PubMed1991

2-Acetylfuran, a confounder in urinalysis for 2,5-hexanedione as an n-hexane exposure indicator.

The apparent amount of 2,5-hexanedione, a biomarker of n-hexane expsoure in occupational health, in the urine of both exposed and non-exposed subjects varied not only as a function of the pH at which the urine sample was hydrolyzed but also depending on the capillary column used for gas chromatographic (GC) analysis of the urinary hydrolyzates after extraction with dichloromethane. The formation of a compound, identified by gas chromatography-mass spectrometry (GC-MS) as 2-acetylfuran, following acid hydrolysis was a major cause of confounding effects. This compound was hardly separated from 2.5-hexanedione on a capillary column such as DB-WAX, whereas separation could be achieved on a DB-1 capillary column. 2-Acetylfuran was formed when a urine sample was heated at a pH of less than 2 for hydrolysis, and the amount detected in urine did not differ between exposed and non-exposed subjects, indicating that the formation of 2-acetylfuran is independent of n-hexane exposure. When urinary hydrolysis is used, hydrolysis at a pH of less than 0.5, extraction with dichloromethane, and GC analysis on a non-polar capillary column are proposed to be the best analytical conditions for 2,5-hexanedione analysis in biological monitoring of exposure to n-hexane.

Confounding Factors, Epidemiologic↗
PubMed1991

Methanol in urine as a biological indicator of occupational exposure to methanol vapor.

The exposure-excretion relationship and possible health effects of exposure to methanol vapor were studied in 33 exposed workers during the second half of 2 working weeks. Urinary methanol concentrations were also determined in 91 nonexposed subjects. The geometric mean value for methanol in urine samples from the latter was less than 2 mg/l (95% upper limit of normal, less than 5 mg/l) when log-normal distribution was assumed. Among the exposed workers, the methanol level in urine samples collected prior to the work shift exceeded the 95% upper limit of normal. The time-weighted average intensity of exposure to methanol vapor was measured using personal sampling devices (in which water severed as an absorbent) in 48 cases of methanol exposure (i.e., 2 of the 33 exposed workers failed to provide urine samples, whereas 17 subjects were examined twice). Methanol concentrations in urine were determined in samples collected at the end of the shift from the 48 exposed cases as well as from 30 nonexposed controls. There was a significant correlation between the exposure to methanol vapor at concentrations of up to 5,500 ppm and the levels of methanol measured in the shift-end urine samples. The calculation indicated that a mean level of 42 mg methanol/l urine (95% confidence range, 26-60 mg/kg) was excreted in the shift-end urine sample following 8 h exposure to methanol at 200 ppm (the current occupational exposure limit). Dimmed vision and nasal irritation were among the most frequent symptoms complained during work. Three cases showing clinical signs of borderline significance were identified.

Adult↗
PubMed1991

Dose-dependent increase in 2,5-hexanedione in the urine of workers exposed to n-hexane.

The concentrations of 2,5-hexanedione (2,5-HD), an n-hexane metabolite, and 2-acetylfuran (2-AF) were measured in urine samples from 123 workers who had predominantly been exposed to n-hexane vapor and 53 workers who had experienced no exposure to solvents. The time-weighted average intensity of exposure to n-hexane vapor was determined by a diffusive sampling method. For biological monitoring of exposure, urine samples were collected late in the afternoon during the second half of a working week and were analyzed in the presence and absence of acid hydrolysis (at pH less than 0.5) for 2,5-HD and 2-AF by gas chromatography on a nonpolar capillary DB-1 column. The urinary 2,5-HD concentration increased as a linear function of the intensity of exposure to n-hexane, showing a correlation coefficient of 0.64-0.77 after acid hydrolysis and that of 0.73-0.83 in the absence of hydrolysis, depending on the correction for urinary density (P less than 0.01 in all cases, with no improvement in the coefficient occurring after the corrections). In contrast, 2-AF levels were independent of n-hexane exposure. The geometric mean 2,5-HD concentration in urine samples from 53 nonexposed men was 0.26 mg/l as observed (i.e., with no correction), 0.19 mg/l after correction for a urinary specific gravity of 1.016, and 0.23 mg/g creatinine after correction for creatinine concentration, and the geometric standard deviation was approximately 2.

Chromatography, Gas↗
PubMed1991

Urinary methylhippuric acid isomer levels after occupational exposure to a xylene mixture.

The quantitative relationship between exposure to xylene vapor and urinary excretion of methylhippuric acid (MHA) isomers were studied in the second half of a working week. The participants in the study were 121 male workers engaged in dip-coating of metal parts who were predominantly exposed to three xylene isomers. The intensity of exposure measured by diffusive sampling during an 8-h shift was such that the geometric mean vapor concentration was 3.8 ppm for xylenes (0.8 ppm for o-xylene, 2.1 ppm for m-xylene, and 0.9 ppm for p-xylene), 0.8 ppm for toluene, and 0.9 ppm for ethylbenzene. Urine samples were collected at the end of the shift and analyzed for metabolities by HPLC. The statistical analysis showed that there is a linear relationship between the intensity of exposure to xylenes and the concentration of MHA in urine, that the regression line passes very close to the origin, and that the increment in observed (i.e., noncorrected) MHA concentrations as a function of increasing xylene concentration was 17.8 mg x l-1 ppm-1. Further examination on the basis on individual xylene isomers showed that the slopes of the regression lines for o- and m-isomers were similar (i.e., 17.1 and 16.6 mg l-1 ppm-1, respectively), whereas that for p-xylene was larger (21.3 mg l-1 ppm-1).

Air Pollutants, Occupational↗
PubMed1991

Genotoxicity of beryllium, gallium and antimony in short-term assays.

The genotoxicity of beryllium, gallium and antimony compounds was studied with the rec, Salmonella mutagenicity and SCE assays. In the rec assay, all the salts of the metals, BeCl2, Be(NO3)2, GaCl3, Ga(NO3)3, SbCl3, SbCl5, and an oxide, Sb2O3, had DNA-damaging activity. None of the compounds was mutagenic to Salmonella. In the SCE assays using V79 cells, 2 antimony(III) compounds, SbCl3 and Sb2O3, and 2 beryllium compounds, BeCl2 and Be(NO3)2, induced SCEs significantly. Sb2O3, slightly soluble in water, was positive in both the rec assay and the SCE assay at very low doses.

Animals↗
PubMed1991

If the fetus can vocalize, how can we detect it?

In this paper, a method to detect the vocal activities of the fetus is reported. An estimation of the intensity and frequency of the voice was made on the assumption that the fetus can vocalize. Based upon these results, experiments to detect the voice were made. From the analysis of the results, it was made clear that the voice seemed to be buried in the noise and difficult to detect.

Female↗
PubMed1991

A questionnaire study on fatigue symptoms of municipal personnel.

The following questionnaire surveys were conducted on 390 male personnel who work in one of the public facilities of a certain city. 1) Fatigue surveys: Using the Fatigue Scale of Industrial Fatigue Research Committee, questionnaire investigations were carried out twice, before work and after work. 2) Health surveys: Using Cornell Medical Index, the neurotic tendency was examined. When the correlation factors of average complaints frequencies were analyzed, indoor workers showed a type of mental task before and after work, whereas outdoor workers showed a type of mental task before work, but showed a general type after work. The workers in generation below thirty-five years mainly showed a type of mental task, while complaints about physical disintegration were relatively frequent in generation above fifties. We consider such questionnaire researches at each work site will constitute a useful clue for examining and ameliorating workers' fatigued condition which may exist inordinately in daily duties.

Fatigue↗
PubMed1991

Erythrocyte deformability in workers exposed to lead.

Erythrocyte deformability and other hematological indicators were determined in 17 male workers exposed to lead at a secondary lead refinery and 13 controls. Blood lead, urine lead, urine coproporphyrin, delta-aminolevulinic acid and erythrocyte zinc protoporphyrin were determined to evaluate the degree of lead exposure in the lead workers above. For the measurement of erythrocyte deformability, the microfilter method was used. The results were summarized as follows: 1. The mean values of blood lead, urine lead, urine coproporphyrin, urine delta-aminolevulinic acid and erythrocyte zinc protoporphyrin levels in lead workers were 53.5 micrograms/100g, 141.4 micrograms/l, 115.9 micrograms/l, 12.0 mg/l and 68.9 micrograms/dl respectively, suggesting a moderate influence of lead exposure. 2. The mean values of erythrocyte count, hematocrit and hemoglobin were significantly lower in lead workers than those in controls. No significant differences were found in the mean values of mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration and corpuscular natrium and potassium between lead workers and controls. 3. Erythrocyte deformability was significantly reduced in lead workers compared with controls.

Adult↗
PubMed1991

A case of lead poisoning recovered by transposition of the work post.

A case of lead poisoning in a secondary lead refinery was reported. A 58 year old man working at the post of lead refining complained of severe lassitude and diarrhea. By increased urine coproporphyrin excretion, he was suspected of a case of lead poisoning. Clinical data from the health examinations revealed that he had been affected by lead. The patient was transposed to another work post where lead was not handled and rapidly recovered from the poisoning.

Follow-Up Studies↗