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Y Sera

Publications and source records attributed to Y Sera.

At least 73 records · Page 4Linked to original sources
PubMed1993

A descriptive epidemiological study on pleural plaque cases identified from the worker's periodical health examinations in Kitakyushu, Japan.

Thirty-six pleural plaque (PP) cases, were identified from the worker's periodical health examination and were described in terms of its association with occupational exposure to asbestos and radiographic findings. Based on thorough interviews about job histories, 23 (64%) of the cases were classified to have had "definite" and an additional 5 (14%) with "possible" asbestos-exposed job histories. Asbestos-exposed job histories were represented mostly by plumbing and pipe fitting, insulating, and boiler and pipe insulating. The latency period between initial age of asbestos exposure and age at time of initial plaque detection was 31.1 +/- 10.3 yr. Calcified plaques were most prevalent in the diaphragm and the most frequent combination of multi-site PPs was found in the diaphragm and lung fields. All cases were either current or ex-smokers. The findings suggest that subjects with a history of asbestos exposure can be identified through the detection of PPs in chest X-ray films obtained in the worker's periodical health examinations.

Adult↗
PubMed1993

Evaluation of low-level asbestos exposure by transbronchial lung biopsy with analytical electron microscopy.

To improve diagnostic sensitivity for detecting low-level asbestos exposure (AEx) in patients, a new method was developed using an analytical transmission electron microscope (ATEM) for specimens of transbronchial lung biopsy (TBLB). The TBLB specimens from 28 patients were examined and the results were: 1) In cases with long-term AEx, the present method detected a large amount of asbestos fibers (AF) as well as asbestos bodies (AB) showing a good agreement with the results of light microscope (LM) which detected definite amounts of ferruginous bodies (FB). 2) In cases with short-term or suspected AEx, the LM failed to detect FB in some cases, but an appreciable amount of AF was detected using the present method, and AEx was disclosed through a second close interview. 3) Neither AB nor AF were detected in most of the cases without any dust exposure. Although small amounts of chrysotile fibers were observed in some cases, this might simply reflect the exposure level of urban dwellers. These results show that the ATEM applied to the TBLB specimens promises to confirm low-level AEx in such small specimens even if the patients were unaware of their past AEx.

Adult↗
PubMed1991

Different genomic and metabolic patterns between mass screening-positive and mass screening-negative later-presenting neuroblastomas.

The mass screening of neuroblastoma has been undertaken in Japan by measuring urinary vanillylmandelic acid (VMA) and homovanillic acid (HVA) in all infants at the age of 6 months. This program may not only improve the prognosis but also provide important insights into the biology and evolution of human neuroblastoma. The authors studied and discuss the clinical significance of the N-myc oncogene, catecholamine metabolism, and other tumor markers in 43 patients with neuroblastoma who underwent the urinary screening test at 6 months of age. Thirty patients were found by the screening, and 13 were negative at the screening but later had a tumor. In the former group, the tumors were mostly in early stages (Stage I, 12; Stage II, 11; Stage III, seven), no amplification of N-myc was observed, and all patients are alive without disease. Although two patients whose urine at the screening showed elevated VMA and HVA levels and accidentally were not treated for 13 and 17 months, there was no change in the values of VMA and HVA during that time. However, in the latter group, the tumors were mostly in advanced stages (Stage I, one; Stage III, four; Stage IV, eight) and N-myc amplification was observed in seven of 13. Only two of these 13 are alive without disease. The age at diagnosis of the screening-negative group was 23 months compared with 8 months in the patients identified by screening, and the pattern of catecholamine metabolites in the screening-negative group tended to be dopaminergic with a low VMA-HVA ratio, especially in cases with N-myc amplification. These data suggest that the screening-positive patients with neuroblastoma may have favorable characteristics, and the biology of these tumors may be different from that of screening-negative later-presenting tumors. They also suggest that there may be at least two distinct subsets of neuroblastoma. For the early detection of the poor prognostic neuroblastomas, the measurement of urinary dopamine with VMA and HVA at later ages, such as 1 to 2 years, should be considered.

Adrenal Gland Neoplasms↗
PubMed1991

[A retrospective cohort study of workers in small asbestos industries in south Osaka].

A retrospective cohort study was carried out on asbestos workers who had received health examinations in 1972 to 1974 conducted by the Osaka Health Center. The subjects, total of 789 (329 males, 460 females) were followed-up for 10 years (Jan. 1, 1975-Dec. 31, 1984). There were sixty-one deaths in the cohort--4 tuberculosis, 12 malignant neoplasms (4 stomach cancers, 8 respiratory cancers including one case of pleural mesothelioma), 18 circulatory diseases, 24 respiratory diseases, and 3 other causes of death. Standardized mortality ratio (SMR) was calculated age and sex-specific death rates for the general population in Osaka between 1975-79 and 1980-84. SMR for all causes of death, stomach cancer, respiratory cancer, circulatory diseases, and respiratory diseases were 1.15, 3.29, 0.75, 3.88, 0.93 and 8.63 respectively. Respiratory cancer and respiratory diseases showed statistically significant (p less than 0.01) excess death with a mean death age of 59 and 56 years old respectively.

Adolescent↗
PubMed1990

Problems of mass screening for neuroblastoma: analysis of false-negative cases.

The Japanese mass screening (MS) system for neuroblastoma at 6 months of age has resulted in the earlier diagnosis of the tumor with excellent therapeutic results. However, some problems are involved in the present MS system. We present six false-negative cases, ages ranging from 1 year 11 months to 3 years 11 months. Neuroblastoma cell taken from four of these patients were studied biologically. These patients had advanced disease (one was stage III; five were stage IV). Three of the patients have died and one is terminally ill despite undergoing surgery combined with intensive chemotherapy. Cytogenetic analysis performed in three cases showed that all the cases had diploid chromosome mode associated with 1P-, double minutes (DMs), or marker chromosomes. N-myc oncogene analysis, performed in four cases, showed amplification in two; one patient had diploid chromosomes, but the other was not examined cytogenetically. These findings were strikingly different biologically from those of cases found by MS. The majority of neuroblastomas detected by MS were found to be triploid tumors without N-myc amplification. These findings suggest that the main reason for the false-negative results in the patients we examined is that they were tumor-free or the tumors were so small in size that they were unable to produce urinary vanillylmandelic acid and or homovanillic acid levels high enough to be detected at the time of MS. Therefore, we conclude that MS at 6 months of age is too early to detect neuroblastoma with a diploid chromosome mode and/or amplified N-myc oncogene. We propose that MS at the age of 1 year 6 months would be more effective to pick up these cases, because treatment strategies depend on the different biological characteristics of tumor cells.

Adrenal Gland Neoplasms↗
PubMed1990

Reduced bone marrow toxicity of neocarzinostatin by conjugation with divinyl ether-maleic acid copolymer.

Neocarzinostatin (NCS) was conjugated with divinyl ether-maleic acid anhydride copolymer (pyran copolymer), and its therapeutic effect was compared with that of NCS. The conjugated NCS (pyran-NCS) with a molecular weight of about 23,000, exhibited in vitro cytotoxic activity against eight cell lines and bone marrow cells that was similar to the cytotoxic activity of NCS on a molar basis. Furthermore, both drugs had similar effects against a multidrug-resistant Chinese hamster ovary cell line (CHR C5) and its parent cell line (AUXB1) in vitro. However, pharmacological analysis showed that pyran-NCS had reduced accumulation in the spleen, and most important was three times less hematotoxic in vivo compared with NCS. Also, pyran-NCS had a 1.7-fold higher 50% lethal dose (LD50). Antitumor activity of pyran-NCS and NCS was tested against two different forms of Meth A tumor. In a solid tumor model, pyran-NCS and NCS suppressed tumor growth at three-fourths of the LD50 to 12.8 and 19.0% of the control tumor as evaluated on day 28, respectively (P less than 0.025). In an ascitic tumor model, the percentage increase in the median life span caused by pyran-NCS and NCS was more than 400 and 150% on day 60, respectively. Pyran-NCS is more effective than NCS because the reduced acute toxicity permits an increased drug dosage.

Animals↗
PubMed1990

[Twenty years' follow-up study of asbestos workers].

This report describes a cohort study conducted on workers who were employed in a factory mainly manufacturing asbestos yarn and cloth and were followed from 1964 to 1981. A total of 208 workers (73 males and 135 females) could be traced and 15 deaths were observed by the end of 1983. Among them, three had lung cancer and its relative risk was 6.8 (p less than 0.05) computed based on the age, sex and year specific death rates of Osaka Prefecture. One case of peritoneal mesothelioma was also found. The period from first asbestos exposure to death of these four cases of asbestos-related malignancies was more than 25 yr. In the analysis of the employees who had more than 1 yr of exposure to asbestos and those who had already been engaged in this factory at the beginning of the observation, the relative risk of lung cancer was 8.1 and 13.6, respectively.

Adult↗
PubMed1990

Gut formation after transection of the midgut loop in the chick embryo.

The primitive gut in vertebrates can be divided into the foregut, midgut, and hindgut. The midgut forms the midgut loop or the intestinal loop, which rotates as it develops the small and large intestines. We examined the effects of transection of the midgut loop on the subsequent development of the intestine in chick embryos by their out-of-the-shell incubation. The development of the embryo and the intestines out of the shell was nearly identical to that usual in-the-shell incubation. The rotation of the midgut loop began in stage 27 (5 days of incubation) and was completed in stage 36 (10 days of incubation) after counterclockwise rotation through 180 degrees. In experimental groups, the midgut loop was transected immediately before or in the early stages of rotation (stages 27-33) proximally or distally to the apex of the loop. Transecting of the midgut loop caused little effects on its subsequent rotation regardless of the time or the site of transection although the secondary loop formation of intestine was poor in some cases. The stumps of the transected intestine were repaired and closed. After closure of the stumps, the proximal segment of the intestine was dilated in some cases. The secondary loop formation, or convolution of the intestine didn't occur in some dilated cases.

Animals↗
PubMed1989

Serial ultrasonic examination to differentiate biliary atresia from neonatal hepatitis--special reference to changes in size of the gallbladder.

We performed serial ultrasonic examinations to differentiate biliary atresia from neonatal hepatitis. The subjects studied were 144 children (100 normal neonates and infants, 31 patients with neonatal hepatitis and 13 patients with biliary atresia). They were examined by ultrasound before, during and after feeding. In 97 out of 100 normal children and all patients with neonatal hepatitis, the gallbladder was identified, and the change in size following oral feeding was observed. In four children with severe neonatal hepatitis which could not be differentiated from biliary atresia by clinical and laboratory data, we readily identified the gallbladder and observed the change in the size following oral feeding. In 8 of 13 patients with biliary atresia, we identified a small gallbladder whose size was not affected by oral feeding. In the other patients the gallbladder was not identified before, during or after oral feeding. On the basis of these results, we consider that serial ultrasonic examination with oral feeding aids in a differential diagnosis of biliary atresia and neonatal hepatitis.

Biliary Atresia↗
PubMed1989

Improved survival rates in children over 1 year of age with stage III or IV neuroblastoma following an intensive chemotherapeutic regimen.

Combined chemotherapeutic regimens of (1) cyclophosphamide (40 mg/kg x two days), (2) cisplatinum (20 mg/m2 x five days) plus VM-26 (100 mg/m2), and (3) Adriamycin (60 mg/m2) plus DTIC (250 mg/m2 x five days) were prescribed for 42 Japanese children greater than 1 year of age with stage III or IV neuroblastoma. The protocol was separated into three forms (A, B, and C) from the combination pattern of three such high-dose courses. The cumulative survival rates for those with stages III and IV 48 months after initiation of therapy were 76.2% and 20.1%, respectively, and the overall rate was 36.7%. The tumor disappeared during the course of treatment in 25 of 42 children (59.5%). The 48-month survival rate was superior in patients greater than 5 years of age than younger patients (P less than .01). Even in patients with a tumor originating in the suprarenal region, the 48-month survival rate was 30.5%. Among 12 patients in whom the N-myc oncogene was measured, one of five with one to ten copies of amplification died, whereas all seven with greater than ten copies died or had a recurrence. Thus, the present chemotherapeutic regimens, in particular alternate administration of each high-dose course, considerably improved the survival of patients with stage III neuroblastoma. More aggressive protocols are needed for those with stage IV neuroblastoma who are greater than 1 year of age, particularly in those with an amplified N-myc oncogene.

Adolescent↗
PubMed1989

[Evaluation of the self-administered respiratory questionnaire recommended by the Japanese Labour Ministry based on the standardized interviewer-administered BMRC questionnaire].

The self-administered respiratory questionnaire on persistent cough or sputum prepared and recommended by the Japanese Labour Ministry to detect pneumoconiosis was evaluated and compared with the Japanese version of the standardized interviewer-administered respiratory questionnaire developed by the British Medical Research Council (BMRC). The two questionnaires were given to 800 subjects on the same day. Because the wording of the questions was similar, the two questionnaires yielded very similar results. In terms of the overall prevalence of persistent cough or sputum, no important differences could be demonstrated between the results of the two questionnaires. The results of this study indicate that the self-administered questionnaire has good concordance with the BMRC questionnaire. When compared to the BMRC questionnaire, the specificity of the self-administered questionnaire was found to be more than 99%, but the sensitivity was inferior to the specificity, being less than 80%. When confined to subjects with persistent cough or sputum for two years or more, the sensitivity was up to 84%. These findings suggest the responses of the subjects to the self-administered questionnaire tend to be negative. A validity of the self-administered questionnaire needs to be further studied among dust workers including pneumoconiotics.

Adult↗
PubMed1989

Asbestos fibre content of lungs with mesotheliomas in Osaka, Japan: a preliminary report.

That crocidolite and amosite are both associated with the development of mesothelioma is now well established, but earlier studies have failed to find an excess of chrysotile in lungs with mesotheliomas as compared with the amounts in lungs of unaffected controls. In an attempt to clarify the importance of fibre type in tissue, an examination of a series of mesotheliomas is being undertaken in Osaka, Japan. A total of 23 mesotheliomas and 5 rejected cases reviewed by the Osaka Mesothelioma Panel were examined for the types of asbestos and semiquantitative fibre content by means of a transmission electron microscope equipped with energy-dispersive X-ray analyser. Asbestos fibres were detected in 19 of the 23 mesotheliomas (21 pleura, 1 pericardium, 1 peritoneum; 19 males, 4 females). Amphibole fibres were found in 13 cases. Five pleural and one peritoneal mesothelioma were found to have only chrysotile fibres. One female pleural mesothelioma with neighbourhood exposure had short chrysotile fibres. Among the 5 rejected cases, only one case with occupational exposure had both chrysotile and amosite fibres. A group of 17 controls were also examined and asbestos fibres were found in 5. Our data, while not definitive, suggest that mesotheliomas can be induced in humans, not only by crocidolite and amosite, but also by chrysotile, though possibly to a lesser extent.

Asbestos↗
PubMed1987

A case of amputation neuroma presenting proptosis.

A case of amputation neuroma, presenting incidious proptosis, was reported in a 44-year-old man. To the best of our knowledge the case seems to be the first report of amputation neuroma caused by trauma in the orbita.

Adult↗
PubMed1986

Respiratory diseases in hard metal workers: an occupational hygiene study in a factory.

A hygiene study of a hard metal factory was conducted from 1981 to 1984. All workers exposed to hard metal were medically examined and their exposure to cobalt measured. Eighteen employees had occupational asthma related to exposure to hard metal, a prevalence rate of 5.6%. Nine had a positive bronchial provocation test to cobalt and reactions of the immediate, late, or dual type were elicited. Exposure measurements suggest that asthma may be caused by cobalt at a mean time weighted average concentration below 0.05 mg/m3. Only two of the nine individuals with cobalt asthma had a positive patch test to cobalt. Chest radiographs of three workers showed diffuse shadows of category 1 or over. X ray microanalysis of lung biopsy specimens from two of these three workers showed the presence of tungsten, titanium, cobalt, nickel, and some minerals. One of the two was diagnosed as having pneumoconiosis due to exposure to silica in a steel industry and the other was suspected of having pulmonary fibrosis caused by dust generated from the carborundum wheels used to grind hard metal. There were no cases with interstitial pneumonitis in the factory.

Adult↗