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Biomedical subjects

J C Luo

Publications and source records attributed to J C Luo.

At least 55 records · Page 3Linked to original sources

Correlations of chronic hepatitis B virus infection and cigarette smoking with elevated expression of neu oncoprotein in the development of hepatocellular carcinoma.

To investigate the potential role of neu oncogene expression in hepatocarcinogenesis, a nested case-control study was conducted within a cohort of 9691 male adults in Taiwan. Blood samples of study subjects were collected during 1984-1986 and frozen at -30 degrees C until subsequent analysis. The neu oncoprotein level in the stored serum was measured by an enzyme-linked immunosorbent assay for 27 cases of newly developed hepatocellular carcinoma (HCC), 12 liver cirrhosis cases, and 40 healthy controls. The mean level of neu oncoprotein was significantly higher in HCC and liver cirrhosis cases than in controls. The risk of HCC increased significantly with increasing serum level of neu oncoprotein (trend test, P = 0.02). The proportion of subjects having an elevated serum level of neu oncoprotein, defined as a level greater than the mean level of all controls, was significantly higher among asymptomatic HBsAg carriers than noncarriers (P = 0.05), showing a multivariate-adjusted odds ratio of 4.0. Among HCC cases, a strong association was observed between cigarette smoking and elevated prediagnostic serum level of neu oncoprotein. The association remained highly significant (P = 0.017) even when adjustment was made for potential confounders. The multivariate-adjusted odds ratio of having an elevated serum level of neu oncoprotein, defined as a level greater than the mean plus 1 SD of control levels, for HCC cases who smoked more than 10 cigarettes a day was as high as 386.5 compared with the cases who smoked less than 10 cigarettes a day or nonsmoking cases. The results suggest that both HBsAg carrier status and cigarette smoking are related to the increased expression of neu oncogene, and cigarette smoking seems to play a significant role in the latter stages of hepatocarcinogenesis. There was no association between alcohol drinking and serum neu oncoprotein level.

Adult↗

Detection of increased amounts of the extracellular domain of the c-erbB-2 oncoprotein in serum during pulmonary carcinogenesis in humans.

Over-expression of the c-erbB-2 oncogene-encoded p185 protein product has been implicated in the pathogenesis of a wide variety of human malignancies, including lung cancer. Over-expression of p185 can be detected immunologically by quantification of the extracellular domain of p185 (c-erbB-2 oncopeptide) in extracellular fluid in vitro and in serum in vivo. An enzyme-linked immunosorbent assay (ELISA) for the c-erbB-2 oncopeptide was used to examine banked serum samples of 11 pneumoconiosis patients who subsequently developed lung cancer and serum samples from 11 hospital controls matched for age, sex, ethnic group and smoking as well as 55 unmatched general population controls. The mean serum level for the c-erbB-2 oncopeptide in human neu units/ml in the lung cancer cases (1,756 +/- 549 HNU/ml) was statistically significantly elevated (p < 0.001) in comparison to the mean level in the matched controls (976 +/- 488 HNU/ml) or the general population controls (888 +/- 655 HNU/ml). Defining a positive elevation of the serum c-erbB-2 oncopeptide as any value more than 2 standard deviations above the mean of the matched controls, 64% (7 of 11) of the lung cancer cases were positive compared to 0% (0 of 11) matched controls and 5% (3 of 55) of the unmatched controls. In addition, 4 of the 7 c-erbB-2 oncopeptide-positive cancer cases had positive serum samples prior to the time of disease diagnosis (average = 35 months). These results suggest that serum c-erbB-2 oncopeptide may be elevated at an early stage of pulmonary carcinogenesis and that further prospective study of the utility of this biomarker is warranted.

Aged↗

Detection of serum p53 protein in lung cancer patients.

Serum levels of p53 protein were examined in 23 cases of lung cancer (many with potential asbestos exposure), 23 unexposed matched hospital control subjects, 58 unmatched general population control subjects, and 4 people with nonmalignant lung disease using an enzyme-linked immunosorbent assay and Western immunoblotting. Average levels of serum p53 in the lung cancer patients (0.55 ng/mL) were higher than in the cases of nonmalignant lung disease (0.42 ng/mL) or in the matched (0.32 ng/mL) or unmatched (0.31 ng/mL) control subjects, but the differences were not statistically significant. However, three of the cases of lung cancer (13%) were found to have serum p53 levels much greater than those of the control subjects (> 2 SD above the mean) and to have confirmatory positive Western blots for p53. The tumors from these subjects demonstrated increased levels of p53 in the tissue by immunohistochemistry and/or the presence of mutations in the p53 gene. These results suggest that p53 protein can be detected in serum in a portion of lung cancer cases with p53 alterations in the tumor tissue.

Aged↗

The detection of increased amounts of the extracellular domain of the epidermal growth factor receptor in serum during carcinogenesis in asbestosis patients.

Overexpression of the epidermal growth factor receptor (EGFr) has been implicated in the pathogenesis of a wide variety of human malignancies and may be related to asbestos-induced carcinogenesis. Overexpression of the EGFr can be detected immunologically by quantitation of the extracellular domain (ECD) in the extracellular fluid in vitro and in serum in vivo. An enzyme-linked immunosorbent assay (ELISA) for the EGFr ECD was used to examine banked serum samples of 38 asbestosis patients who subsequently developed cancer, 72 age-sex-race-smoking-asbestos exposure matched asbestosis controls without cancer, and 20 age-sex-race-smoking matched nonasbestosis noncancer controls. The mean serum level for the EGFr ECD in the cancer cases (636 +/- 299 fmol/ml) was statistically significantly elevated (P < 0.05) in comparison to the mean level in the asbestosis controls (546 +/- 147 fmol/ml) or the nonasbestosis controls (336 +/- 228 fmol/ml). Defining a positive elevation of the serum EGFr ECD as any value more than 2 standard deviations above the nonasbestosis control mean, 7 (18%) of the cancer cases were positive compared to 4 (6%) of the asbestosis controls and one (5%) of the nonasbestosis controls. In addition, all of these cancer cases had positive serum samples prior to the time of disease diagnosis (average = 5.1 years). These results suggest that serum EGFr ECD may be elevated at an early stage of carcinogenesis in some asbestosis patients and that further prospective study of the utility of this biomarker is warranted.

Adult↗

Phenotypic aberrations of CD3+ and CD4+ cells and functional impairments of lymphocytes at low-level occupational exposure to lead.

To study the immunological effects of low-level occupational exposure to lead, we have examined the phenotypic parameters and functional integrity of peripheral blood lymphocytes in a group of firearms instructors and compared the data to those obtained from healthy unexposed controls. Our results indicate that, among individuals with mildly elevated blood lead levels (> 25 micrograms/dl), detrimental effects on the host's immune functions occur. Such dysfunctions are multicellular as to mechanism and dose dependent in nature. The absolute percentage and number of CD3+ and CD4+ cells were significantly reduced, while the values for CD8+ cells were unchanged. Functional integrity of T cells as determined by responses to mitogens was impaired while that of T-cell-dependent B-lymphocyte function appeared to be within normal range at all stages of maturation. These data suggest the presence of a defective feedback loop which regulates T-cell-dependent functions and cell-to-cell cooperation. Furthermore, the marked deficiency in MLC responses that was also observed suggests that the adverse effect of lead may be due to its high affinity for the TCR and HLA-DR surface receptors thereby interfering with antigen processing from monocytes to T lymphocytes.

Adult↗

Respiratory findings among millwright and machinery erectors: identification of health hazards from asbestos in place at work.

Asbestos-associated diseases are prevalent in the construction trades primarily because of the previously widespread use of asbestos-containing insulation materials. Workers in metal-related trades, employed at construction sites and power facilities, but who do not routinely handle such materials as part of their work, may also be at risk for significant asbestos exposure. In order to evaluate such risk, a clinical field survey was conducted of 110 millwright and machinery erectors from the New York metropolitan area. A high prevalence of chest roentgenologic abnormalities was found. Forty-nine (44.5%) of the examined workers had pleural abnormalities consistent with asbestos-induced effects. Eighteen workers showed evidence of unilateral pleural thickening. Duration from onset of employment was significantly longer for those with pleural abnormalities (mean 32.3 years) as compared to those with normal chest radiographs (mean 18.5 years). Thirteen workers (11.8%) had radiographic signs of interstitial lung disease. The workers with pleural abnormalities had lower mean values of restrictive and obstructive lung function parameters than those with normal pleura. Multivariate and logistic regression analyses demonstrated association between duration of employment in the millwright trade and pleural abnormalities which was independent of smoking status. These findings suggest that millwright and machinery erectors employed in work environments where there is potential for primarily indirect exposure to airborne asbestos-containing dust are at risk for adverse effects from such exposure.

Adult↗

[Initial investigation of the value of CT in pulmonary metastases originating from head and neck malignant tumors]

CT image and its diagnostic value were analyzed and compared with plain chest film on 12 cases of pulmonary metastases originating from malignant tumors of head and neck,all cases were pathologically verified.CT scan performed on each cases who had definite or suspicious lesion on plain chest film.The result presents that CT can:(1)confirm the suspiciousness of metastatic lesion.(2)confirm the number of metastatic lesion.(3)early detection on pulmonary metastasis. 4.identification on occult pulmonary metastasis. 5.Find out costal bone and pleural metastasing accuracy of pulmonary metastasis,but also provide information for clinical selecting treatment.

Journal Article↗

Serum growth factors and oncoproteins in firefighters.

Firefighters are potentially at increased risk for cancer and non-malignant respiratory disease due to their toxic exposures on the job. Growth factors and oncogene proteins are thought to play a role in the development of various malignancies and pulmonary fibrotic diseases. Therefore, a cohort of firefighters and matched controls have been screened for the presence of nine different growth factors and oncoproteins using an immunoblotting assay. Fourteen of the firefighters were found to be positive for beta-transforming growth factor (beta-TGF) related proteins compared to no positives in the controls (P = 0.0017). These results suggest that beta-TGF may be a possible biomarker for monitoring firefighters and other exposed workers for the potential development of cancer or non-malignant respiratory disease.

Amino Acid Sequence↗

Clinical findings among hard metal workers.

In 1940, the first report appeared describing a pulmonary disorder associated with occupational exposures in the cemented tungsten carbide industry. The disease, known as "hard metal disease," has subsequently been characterised in detail and comprises a wide range of clinical signs and symptoms. In this report, clinical findings in a group of 41 hard metal workers employed until recently are described. A high prevalence of respiratory symptoms was found. Thirteen workers (31%) had abnormal chest radiographs indicative of interstitial lung disease. Fifty per cent of these had been employed in hard metal manufacturing for less than 10 years. Abnormalities of pulmonary function were also frequent and included a restrictive pattern of impairment and decrease in diffusing capacity (27%). Associations were found between diffusing capacity, chest radiographic abnormalities and right ventricular ejection fraction at exercise indicating cardiopulmonary effects. The findings show the continuous need to control excessive occupational exposures to prevent hard metal disease, the history of which now enters its sixth decade.

Adolescent↗

Low level and bystander exposure to lead among factory workers.

A clinical field survey of 36 workers employed in the manufacturing of leaded products used in radiologic safety was conducted. Although the principal source of lead exposure was limited to an area where two individuals mixed lead oxide and vinyl liquid, increased lead absorption was found in other workers employed in adjacent areas. The mean lead concentration of the plant workers was 29.3 micrograms/dL (SD +/- 9.0), and four workers had blood lead levels of 40 micrograms/dL or higher. A statistically significant correlation was noted between blood lead and serum creatinine; linear regression analysis demonstrated that cigarette smoking was a significant factor in predicting the blood lead level. The exposure encountered in this plant may be typical of lead exposure in many similar industrial settings. It calls attention to the risk of excessive exposure among workers who are not working at the primary source of exposure, and should be considered in the design of medical surveillance programs for workers employed in small manufacturing plants.

Adult↗

Asbestosis, laryngeal carcinoma, and malignant peritoneal mesothelioma in an insulation worker.

Asbestos associated diseases consist of both benign and malignant conditions. A rare constellation of asbestosis, laryngeal carcinoma, and malignant peritoneal mesothelioma occurring in a patient with long term occupational exposure to airborne asbestos fibres is presented. The observation illustrates the powerful disease-causing potential of occupational exposure to asbestos. A brief discussion of multiple primary neoplasms associated with exposure to asbestos is also presented.

Aged↗

Respiratory findings among ironworkers: results from a clinical survey in the New York metropolitan area and identification of health hazards from asbestos in place at work.

Diseases associated with asbestos are prevalent in the construction trades primarily as the result of the previously widespread use of insulation materials containing asbestos in the building industry. Workers in metal related trades, who are employed at construction sites, but who do not routinely use such materials in their work, may also be at risk for asbestos hazards. To assess such risk, a clinical survey was conducted on 869 ironworkers from the New York metropolitan area. A high prevalence of abnormalities on chest radiographs was found. Three hundred and twenty nine (38%) of the examined workers had pleural abnormalities on their chest radiographs consistent with asbestos induced effects. The prevalence of radiographic abnormalities indicating interstitial lung disease was low (7%) as was the prevalence of restrictive pulmonary function impairment (7%). Association was found between forced vital capacity (FVC) and pleural abnormalities on chest radiographs. Although ex-smokers appeared to have the highest prevalence of abnormalities, regression analyses showed that duration of employment in the ironworkers' trade was the most important factor associated with them.

Asbestos↗

Indirect lymphography with Isovist-300 in various forms of lymphedema.

Twenty patients with various forms of lymphedema were studied by indirect lymphography. Isovist, a new non-ionic, water-soluble, dimeric contrast media, was used for intradermal infusion. Simultaneous indirect lymphography showed characteristic patterns of lymphatics. The initial lymphatics were visualized by intradermal infusion of the newly developed isovist. However, they were not opacified with direct lymphography unless in the presence of valvular insufficiency. No systemic side-effects were observed except for a feeling of discomfort at the injection site. The results showed that indirect lymphography with intradermal infusion of Isovist is useful for demonstrating dermal lymph vessels and for the diagnosis of lymphedema.

Adolescent↗

Persistent reactive airway dysfunction syndrome after exposure to toluene diisocyanate.

Two police officers developed asthma like illness after a single but prolonged exposure to toluene diisocyanate (TDI) by being in the immediate vicinity of a tank car that had overturned on a highway. One officer experienced upper and lower respiratory tract symptoms with chest tightness about 4.5 hours after initial exposure. Shortness of breath, cough, and wheezing were noted the following day. The other experienced symptoms immediately on exposure, developed shortness of breath 20 minutes later, and presented with wheezing four hours after that. Follow up examinations over seven years showed persistence of respiratory symptoms and continuation of airway hyperreactivity requiring treatment.

Accidents, Traffic↗

Exposure to epichlorohydrin and dimethylformamide, glutathione S-transferases and sister chromatid exchange frequencies in peripheral lymphocytes.

Workers in epoxy resin, synthetic leather, and printed circuit board manufacturing plants are exposed to epichlorohydrin (ECH), or dimethylformamide (DMF), or both. ECH, an alkylating agent, has been shown to cause malignancy in animals, but its genotoxicity in humans is unclear. DMF is a well-known hepatotoxic chemical, although evidence of its genotoxicity in humans is also limited. In this study, we examined the effects of exposure to ECH and DMF on sister chromatid exchange (SCE) in plant workers, in order to examine the genotoxicity of these two agents. Because the genotoxicity of certain agents can be modulated by metabolic traits, we also investigated influence of the glutathione S-transferase (GST) micro (GST M1) and GST theta (GST T1) genes on the genotoxicity of ECH and DMF. A total of 85 male plant workers were included in this study. The subjects were divided into five exposure groups, based on their job titles and the airborne ECH and DMF concentrations in their areas of work. A questionnaire was administered to obtain detailed occupational, smoking, alcohol consumption, and medication histories. Standardized cytogenetic methods were used to determine the frequency of sister chromatid exchange (SCE) in peripheral blood lymphocytes. GST M and GST T1 genotypes were identified using polymerase chain reaction (PCR). In analysis, smoking was significantly associated with increased SCE frequency (P<0.01). Workers with high ECH exposure also had significantly higher SCE frequencies than those with low or no ECH exposure (P<0.05). However, DMF exposure was not associated with SCE frequency. The GST M1 null genotype was also found to be associated with an increased SCE frequency (P = 0.06). We conclude that ECH exposure may be associated with genetic toxicity and that DMF does not appear to be genotoxic.

Adult↗

Tuberculous peritonitis in a geriatric patient: a case report.

In geriatric patients with exudative ascites, malignant ascites is a common etiology. Tuberculous peritonitis is rarely seen and usually overlooked. We describe a 67-year-old man who suffered from exudative ascites for 1 month before admission. None of the noninvasive diagnostic methods utilized enabled us to make a correct diagnosis. Peritoneoscopic examination demonstrated multiple whitish miliary nodules and some larger nodules in the parietal and visceral peritoneum. Excisional biopsy confirmed the diagnosis of tuberculous peritonitis. This case reminds us that although malignant ascites is more prevalent in geriatric patients with exudative ascites, peritoneoscopy is indicated when noninvasive diagnostic methods allow no definite diagnosis.

Aged↗