Biomedical subjects

T Higashi

Publications and source records attributed to T Higashi.

At least 19 recordsLinked to original sources

PubMed1992

Four-year follow-up of effects of toluene diisocyanate exposure on the respiratory system in polyurethane foam manufacturing workers. I. Study design and results of the first cross-sectional observation.

A 4-year cohort study was designed to assess the exposure-effect relationship of working in polyurethane foam (PF) manufacturing factories with exposure to toluene diisocyanate (TDI) and its effects on the respiratory system. This paper describes the results of the first cross-sectional observations. The study population included 90 male workers who had been working in PF factories for 0.5-25 years (mean 13.3 years) (PF workers) and 44 reference workers in the same factories. The mean exposure concentration of TDI calculated from 129 personal samples was 3.2 ppb. Peak exposure excursions above 20 ppb occurred in 16 of 129 samples. Pulmonary function and its change during the working day as assessed by examining the forced expiratory flow-volume curve, respiratory impedance, and airway resistance and specific airway conductance were not different in the PF workers from those in the reference workers. Chest X-radiographs did not show any noteworthy radiological changes. Prevalences of "phlegm in winter," "nasal stuffiness or discharge in winter," and "irritation of eye and throat mucous membranes" were significantly higher in the PF workers. The findings indicate that TDI exposure at levels around 3 ppb may not adversely affect the pulmonary function over many years of exposure of those who are not hypersensitive to TDI. The causal chemicals inducing some respiratory and irritative symptoms could not be specifically identified since the PF workers were exposed not only to TDI but also to other irritative agents in the PF manufacturing processes.

Adolescent↗

PubMed1992

Four-year follow-up of effects of toluene diisocyanate exposure on the respiratory system in polyurethane foam manufacturing workers. II. Four-year changes in the effects on the respiratory system.

Fifty-seven polyurethane foam manufacturing workers (PF workers) and 24 reference workers were followed for 4 years to clarify the effects on pulmonary function of working in PF factories with exposure to toluene diisocyanate (TDI). No significant differences in the average annual losses (AALs) of pulmonary function for 4 years were observed among the 28PF workers whose TDI exposure levels were very low (mean = 0.1 ppb, group L), the remaining 29 PF workers with mean TDI exposure of 5.7 ppb (group H), and the reference workers. However, 15 PF workers in group H who had experienced peak exposure excursions to 30 ppb or above with a mean concentration of 8.2 ppb showed significantly larger AALs in percentage maximal mid-expiratory flow, forced expiratory volume in 1 s ratio to vital capacity (FVC), and forced expiratory flow at 25% of FVC than expected, and significantly larger AALs in some obstructive pulmonary function indices than those of the 14 remaining PF workers in group H whose peak exposure excursion levels were 3-14 ppb with a mean time-weighted average (TWA) of 1.7 ppb, group L, and the reference workers. These findings suggest that the peak exposure excursion level of TDI might be important in inducing obstructive pulmonary function changes in the PF workers rather than the TWA exposure levels, though further comparative studies of the AAL in those who are exposed to different peak exposure excursion levels but the same mean exposure levels are necessary. From the standpoint of prevention, the proposition that peak exposure excursion levels exceeding 20 ppb should be avoided is reasonable.

Adult↗

PubMed1992

Treatment of hepatocellular carcinoma by transcatheter hepatic arterial injection of radioactive iodized oil solution.

After 12 days of culture, VX2 carcinoma cells were inoculated into the liver of 16 rabbits; 14 days later, 131I-labeled iodized oil ([131I]-Lp) suspended in lipiodol was injected into the hepatic artery. Selective accumulation of the contrast material in the tumor for an extended time was evident on X-rays and hepatic scintiphotographs. The antitumor effect was remarkable. [131I]-Lp agents warrant further examination for their clinical usefulness. Internal radiation therapy by transcatheter hepatic arterial injection of [131I]-Lp (group A) was evaluated in 9 patients with hepatocellular carcinoma (HCC, tumor stage III or IV) associated with liver cirrhosis (LC) and compared with combination therapy of Lp-TAE (group B) in 18 patients with HCC (tumor stage III or IV) associated with LC. In group A, serum AFP levels dropped rapidly in eight of the nine patients who had an elevated initial level of more than 500 ng/ml. The average reduction in tumor size was 50% in eight cases as determined by computed tomography. Histological examination of one resected liver specimen at 3 months after the third injection of [131I]-Lp revealed microscopic features highly suggestive of a radiation effect in the [131I]-Lp-containing area. The 1-year survival value for patients with HCC was estimated at 49.0% using the Kaplan-Meier method. The survival of patients treated with internal radiation therapy tended to be better than that of those treated with Lp-TAE (P = 0.119).

Aged↗

PubMed1992

Genetic polymorphism of human factor H (HF, beta 1H globulin) in Chinese Han population in northeast China.

The distribution of human factor H of serum phenotypes were studied using ultrathin polyacrylamide gel isoelectric focusing (PAGIEF) and subsequent immunoblotting techniques in 203 Chinese of Han population in Liaoning Province of northeast China. The gene frequencies of HF*A and HF*B were 0.4828 and 0.5172, respectively. All the observed numbers of the phenotypes were in agreement with the expected numbers under the Hardy-Weinberg equilibrium. The gene frequencies among Chinese, Japanese, and Caucasian populations were compared.

China↗

PubMed1992

Long-term course of childhood epilepsy with intractable grand mal seizures.

Twenty-nine children with childhood epilepsy characterized by frequent grand mal (generalized tonic-clonic) seizures in spite of maximal doses of antiepileptic drugs and by an early onset of seizures (before 1 year of age) were followed up for more than 5 years. The children were divided into 3 groups: severe myoclonic epilepsy in infancy (SME), no SME, and intractable childhood epilepsy with generalized tonic-clonic seizures (GTC). In all the 3 groups, the grand mal seizures persisted, whereas the other types of seizures tended to disappear as the patients aged, and the prognosis for mental development was poor. In the majority of cases in all the 3 groups, the waking grand mal seizures altered to sleep grand mal seizures with aging. Two pairs of monozygotic twins with SME suggested that genetic factors play a role in this epileptic syndrome. Intractable childhood epilepsy with GTC is distinguished by the absence of other types of generalized seizures. It cannot be regarded as an epileptic syndrome, but its pathogenesis and treatment require further studies.

Child, Preschool↗

PubMed1992

Determinant factor for clearance of ceramic fibres from rat lungs.

Deposition, clearance, retention, and durability of inhaled particles from lungs are known to be important factors for induction of pulmonary fibrosis or lung cancer. To study the deposition and clearance of alumina silicate ceramic fibres from the lung, male Wistar rats were exposed to ceramic fibre particles with a mass median aerodynamic diameter (MMAD) of 4.2 micron, for six hours a day, five days a week for two weeks. The average exposure concentration was 20.7 (standard deviation (SD) 4.5) mg/m3. The rats were killed at one day, three months, and six months after the end of exposure, and the fibre numbers and dimensions were measured with a scanning electron microscope. No significant differences in number and geometric mean length of residual ceramic fibres in the lungs were found between the groups. The geometric mean diameter, however, decreased according to the duration of the clearance period. These findings suggest that solubility of fibre contributes most in the clearance of the inhaled ceramic fibres from the lungs.

Animals↗

PubMed1992

Biological monitoring of workers exposed to acetone in acetate fibre plants.

Concentrations of acetone in urine, alveolar air, and blood were measured by gas chromatography with flame ionisation detection for 110 subjects occupationally exposed to acetone (mean 372 ppm) in three factories. Significant relations were found between the time weighted average environmental concentration and the concentration in the biological samples. The strongest correlation was between the concentration of acetone in urine and the degree of exposure (r = 0.71, 95% CI 0.64-0.77). This suggests that urinary acetone concentration is the best biological index of occupational exposure to acetone.

Acetone↗

PubMed1992

Rat liver nodules induced by 2-acetylaminofluorene lose an ability to take up indocyanine green in the process of hepatocarcinogenesis.

Indocyanine green (ICG) was injected into rat liver nodules induced by 2-acetylaminofluorene (2-AAF) via portal vein. The relationship between ICG staining and cell atypism of liver nodules was examined by means of histology and DNA flow cytometry. After 2-AAF administration, many small nodules appeared on the liver surface. All hyperplastic nodules were ICG stained until 10 weeks after the administration, but some nodules were not stained after 14 weeks. ICG-stained nodules histologically consisted of benign tissues and borderline lesions, and many of them showed "diploidy" in DNA cytometry. ICG-unstained nodules consisted of hepatocellular carcinoma (HCCs) and borderline lesions, and many of them showed "aneuploidy". In this way, it has been suggested that HCC could derive from hyperplastic nodules and that they might lose an ability to take up ICG in the process of hepatocarcinogenesis. Immunohistochemical staining for glutathione-S-transferase alpha (GST-alpha), a carrier protein of ICG in hepatocytes, was well correlated with ICG staining in the nodules, suggesting that the loss of ICG uptake in HCC was partly due to the decrease of GST-alpha. Moreover, the appearance of ICG unstained and aneuploid nodules was significantly inhibited in rats which were fed on diet containing Syosaiko-to after the administration of 2-AAF. Chemopreventive effect of Syo-saiko-to on hepatocarcinogenesis was identified.

2-Acetylaminofluorene↗

PubMed1992

Follicular bronchiolitis associated with rheumatoid arthritis.

Follicular bronchiolitis is a rare disorder, though it has been recognized as a pulmonary involvement of rheumatoid arthritis in recent years. A 57-year-old woman with rheumatoid arthritis was admitted to the hospital with persistent productive cough and breathlessness on exertion. An open lung biopsy was performed to establish a definite pathologic diagnosis of her disease, and she was diagnosed as having follicular bronchiolitis on the basis of the histopathological findings. It is essential to differentiate this disease from other bronchiolar or lymphoproliferative disorders of the lung.

Arthritis, Rheumatoid↗

PubMed1992

Genetic polymorphism of complement component C6, C7 and C8(1) in Chinese Han population in northeast China.

Distributions of complement phenotypes, C6, C7, and C8(1) were studied using thin agarose gel isoelectric focusing (AGIEF) or ultra-thin polyacrylamide gel isoelectric focusing (PAGIEF) and subsequent immunoblotting techniques in 203 Chinese Han population in Liaoning Province of northeast China. The gene frequencies were as follows: C6*A 0.4704, C6*B 0.5049, C6*B2 0.0148, C6*B3 0.0049, and C6*M 0.0049; C7*1 0.8251, C7*2 0.1108, C7*3 0.0320, and C7*4 0.0320; C8(1)*A 0.5567 and C8(1)B 0.4433, respectively. All the observed numbers of the phenotypes were in agreement with the expected numbers under the Hardy-Weinberg equilibrium. The gene frequencies among Chinese subpopulations and other various populations were compared.

Asian People↗

PubMed1992

[Effect of prostaglandin E1 on peripheral body temperature in pediatric patients after open heart surgery].

The effect of prostaglandin E1 was studied to examine if it works favorably for peripheral circulation in pediatric patients after cardiac surgery. Dose of 0.1 mcg.kg-1.min-1 increased temperature of dorsal pedis significantly. Difference of temperature of dorsalis pedis and that of rectum was significantly smaller than that in control group. A significant increase in heart rate and a decrease in systolic arterial pressure produced no clinical side effects. We conclude that prostaglandin E1 is a useful and safe vasodilator for circulatory management of pediatric patients after cardiac surgery.

Age Factors↗

PubMed1992

Multiple organ failure in patients with fulminant hepatitis and in post-operative patients with liver cirrhosis.

Multiple organ failure (MOF) appeared during the course of nine cases with fulminant hepatitis, and it was compared with that of seven cirrhotic patients with post-operative hepatic failure. The number of organs failed was 4.9 and 3.6 on average in fulminant hepatitis and post-operative cirrhosis, respectively. All the patients died in less than nine days following the occurrence of MOF. Gastrointestinal bleeding was more frequently observed in fulminant hepatitis cases than in cirrhotic patients. In post-operative cirrhotics, hepatic failure occurred later and the elevation of serum total bilirubin was mild and slow. Renal failure and/or gastrointestinal bleeding was observed prior to death in fulminant hepatitis cases, and cardiac failure and hepatic failure in post-operative cirrhotics. These organ failures resulted in death, although extensive and multimodal treatments were carried out in both groups of patients.

Adult↗

PubMed1991

[A fatal rheumatoid pneumonitis following surgery for lung cancer].

A 64-year-old man was admitted to our division because of an abnormal mass with a diffuse reticular shadow seen on chest roentgenogram. A right upper lobectomy was performed after the diagnosis of lung cancer. From the 18th postoperative day he complained of dyspnea, which was caused by the exacerbation of rheumatoid pneumonitis based on rheumatoid arthritis, and died on the 44th postoperative day. The course of illness and clinicopathological analysis of this case is described in this paper.

Arthritis, Rheumatoid↗

PubMed1991

Effect of lead on cardiac parasympathetic function.

A cross-sectional survey was performed on 172 male, lead exposed workers to clarify the effects of lead on the cardiac autonomic nervous system expressed as the decrease of R-R interval variation on an electrocardiogram and to obviate the dose-effect relationship between blood-lead level (Pb-B) and the degree of the decrease. For 132 workers who were exposed to lead for more than one year and whose Pb-B levels were relatively stable (Pb-B variation less than 20 micrograms/dl during recent one year), a significant dose-related decrease of R-R interval variation during deep breathing was observed. Age-adjusted R-R interval variation during deep breathing in those whose Pb-B were 30 micrograms/dl or above was significantly decreased compared with those whose Pb-B levels were 20 micrograms/dl or below. This decrease was observed more clearly in younger workers. These results suggest that an effect on autonomic nervous system expressed as decrease of R-R interval variation during deep breathing might be one of the earliest effects of lead exposure.

Adolescent↗

PubMed1991

A novel point mutation at codon 146 of the K-ras gene in a human colorectal cancer identified by the polymerase chain reaction.

In this report, point mutations of the K-ras gene at codon 146 were analyzed in 25 cases of colon cancer, 4 cases of lung cancer, and 41 cases of lymphoid malignancy. A codon 146 mutation substituting threonine (ACA) for alanine (GCA) was detected in the tumor tissue of a patient with colon cancer and was not detected in the normal tissue of the same patient. Any additional mutations of the ras gene family were not detected in this patient. These results suggest that the codon 146 mutation of the K-ras gene could be involved in the development of naturally occurring human malignancies.

Antisense Elements (Genetics)↗

PubMed1991

Structure and transforming potential of the human cot oncogene encoding a putative protein kinase.

A new transforming gene has been molecularly cloned from hamster SHOK cells transformed with DNA extracted from a human thyroid carcinoma cell line and named the cot (cancer Osaka thyroid) oncogene. cDNA sequencing disclosed that this oncogene codes for a protein with 415 amino acid residues, and computer matching showed 42 to 48% similarity matches with serine protein kinases. Its gene product was identified as a 52-kDa protein by transcription and translation in vitro. Expression of cot cDNA under transcriptional control by a retroviral long terminal repeat induced morphological transformation of NIH 3T3 cells as well as SHOK cells. Protein kinase activity associated with constructed p60gag-cot was detected by immune complex kinase assay with anti-gag antiserum. The cot oncogene was overexpressed in transformed SHOK cells and found to have a rearranged 3' end in the last coding exon, which probably resulted in a deletion and an altered C' terminus in the transforming protein. This DNA rearrangement appeared to have occurred during transfection of the tumor DNA into hamster SHOK cells and not in the original thyroid tumor.

Amino Acid Sequence↗

PubMed1991

A differential study between antemortem bleeding and a postmortem infiltration of hemoglobin.

In a differential study to distinguish antemortem bleeding from a postmortem infiltration of hemoglobin, glycophorins, a component of the erythrocytic membrane, were extracted from two experimental skin tissue models, i.e., skin samples taken on autopsy into which healthy human blood was injected, and skin samples undergoing a postmortem infiltration of hemoglobin; this extraction accomplished by utilizing an anti-glycophorin serum over set periods of time, after which differences between the two models were then evaluated. In all of the bleeding samples from day 0 to day 9, and in 40% of the 12-day-old bleeding samples, glycophorins were clearly detected qualitatively by counterimmunoelectrophoresis and by double-immunodiffusion. In the remaining 12-, 15-, and 18-day-old bleeding samples, glycophorins were only faintly detected by counterimmunoelectrophoresis. Additionally, in a quantitative study by rocket-immunoelectrophoresis, the mean glycophorin value of 0-day-old bleeding samples was 118.5 +/- 5.6 micrograms per 0.5 g of tissue. Further, the recovery of glycophorins from the bleeding samples was satisfactory for up to 9 days, though after 12 days there was a rapid glycophorin decrease. In 15- and 18-day-old bleeding samples, the mean glycophorin values were 19.3 +/- 1.0 and 17.8 +/- 1.0 micrograms per 5 g of tissue, or about 16% and 15% of the 0-day values, respectively. In contrast, no glycophorins were detected in any of the hemoglobin-infiltrated skin samples or our control samples at any time interval. These results suggest that a differential diagnosis between antemortem cutaneous bleeding and postmortem hemoglobin infiltration into the tissue is achievable within 9 to 12 postmortem days.

Cadaver↗

PubMed1991

[Reversal of high-dose fentanyl anesthesia by naloxone: analysis of factors attenuating respiratory and hemodynamic responses to naloxone].

The respiratory and hemodynamic responses to postoperative reversal by naloxone of high-dose fentanyl anesthesia were studied in 101 patients after open heart surgery. Respiratory and hemodynamic changes after drip infusion of naloxone were minimum. Change of systolic blood pressure (BPs), mean blood pressure (BPm), CVP and PO2 were statistically significant. BPs increased for 3.8 +/- 14.0 mmHg, BPm increased for 1.6 +/- 8.2 mmHg. CVP decreased for 0.4 +/- 2.1 mmHg, and PO2 decreased for 8.6 +/- 3.4 mmHg. Severe side effect was not observed. Multi-factorial analysis revealed that the abrupt recovery of consciousness from anesthesia and acidosis were the most important factors that attenuate hemodynamic response to naloxone.

Anesthesia Recovery Period↗