Needs Assessment for the Beneficiaries of Home-Based Cancer Patients Management Project / 農村醫學 地域保健

OBJECTIVES: This study was performed to investigate the service needs of the beneficiaries who had enrolled in home-based management programs for cancer patients. METHODS: From March to May 2009, 676 cancer patients who were registered in home-based cancer patient management programs were selected as subjects for this study. The data were collected using a questionnaire along with a face-to-face interview performed by officers in charge of the home-based care programs of 47 regional health centers. Fifteen patients were excluded due to incomplete data, leaving 661 subjects who were ultimately enrolled in the study. RESULTS: The mean age of subjects was 64.0 +/- 12.5 years, and males comprised 45.1% (298/661) of the sample. The results of factor analysis for service needs showed that there were five main categories and Cronbach's alpha ranged from 0.593 to 0.890 for each factor. The service needs categories in order of importance were social support, information and education, psychological problems, physical symptoms and household chores. The service needs scores were significantly different when subjects were stratified by age, habitation, religion and disease classification. When we divided the subjects into complete remission, under treatment and terminally ill groups, the needs scores of the terminally ill patient group were significantly higher than those of the other groups (p<0.001). CONCLUSIONS: Service provision based on patient and beneficiary needs could be an effective intervention to reduce the economic burden of cancer management and to improve the quality of life of cancer patients receiving home-based care. Therefore, it is recommended that individual cancer patient care programs be developed and administered according to patient age, habitation and disease severity.

The Relationship between Job Stress and Psychosocial Stress among Nurses at a University Hospital / 대한산업의학회지

OBJECTIVES: This cross-sectional study investigated the relationship between job stress and psychosocial stress among nurses at a university hospital in Incheon, Korea. METHODS: A questionnaire survey was administered to 476 nurses, of which 320 (67.2%) questionnaires were returned and 299 (62.8%) were regarded as containing reliable data for analyses. A structured self-reported questionnaire was used to assess each respondent's sociodemographics, sleep quality, physical burden, job stress and psychosocial stress. Seven domains of occupational stress (e.g., Job demand, Insufficient job control, Interpersonal conflict, Job insecurity, Lack of reward, Organizational system and Occupational climates) according to the Korean Occupational Stress Scale (KOSS) were used and psychosocial stress was measured using Dr. Chang's PWI-SF (Psychosocial Well-being Index-Short Form). We estimated the relation of job stress to psychosocial stress using univariate and logistic regression analyses. RESULTS: The logistic regression analyses indicated that the groups with high stress in 'Insufficient job control' (OR=2.67, 95% C.I.=1.37-5.23), 'Interpersonal conflict' (OR=2.32, 95% C.I.=1.19-4.51), 'Job insecurity' (OR=2.51, 95% C.I.=1.17-5.36), 'Organizational system' (OR=2.80, 95% C.I.=1.39-5.63), and 'Lack of reward' (OR=2.98, 95% C.I.=1.55-5.74) were more likely to experience high psychosocial stress. CONCLUSIONS: Our results tend to suggest that job stress is associated with psychosocial stress. The importance of job stress should be acknowledged and stress management programs need to be instigated to minimize the psychosocial stress caused by job stress.

Effects of Selenium on Apoptosis Induced by Methyl Mercury Chloride in RAW 264.7 Cells / 대한산업의학회지

OBJECTIVE: This study was performed to evaluate the protective effects of selenium against the methyl mercury chloride (MeHgCl) induced cell apoptosis. METHODS: The effect of selenium on the MeHgCl induced cell apoptosis was observed in mouse macrophage-derived RAW 264.7 cells, in vitro. The cells were cultured in Dulbecco's modified Eagle's medium (DMEM). RESULTS: MeHgCl exerted a dose dependent cytotoxicity, as demonstrated by the MTT assay, an assay dependent, in part, on mitochondrial function. Concurrent exposure to selenium provided complete protective effects against the cytotoxicity induced by MeHgCl. Pretreatment with selenium increased the protective effects of subsquent administrations of selenium in conjunction with MeHgCl, but pretreatment of selenium alone did not provide protection against MeHgCl when given alone. Selenium administered after exposure to MeHgCl did not repair the existing MeHgCl induced cytotoxicity.Furthermore, the apoptosis induced by MeHgCl was revealed by the DNA fragmentation, using the terminal deoxynucleotidyl transferase Biotin-dUTP nick end labeling (TUNEL) assay, alterations to the nuclear morphology, by nuclei staining, and the plasma membrane lipid organization, as shown by cell flow cytometry. The apoptosis induced by MeHgCl was prevented by the concurrent exposure to selenium, or pretreatment with selenium, prior to the administration of selenium in conjunction with MeHgCl. However, no inhibittion of the MeHgCl induced apoptosis was observed with selenium pretreatment prior to exposure to MeHgCl alone, or with the administration of selenium after exposure to MeHgCl. CONCLUSIONS: These results suggest that the coexistence of selenium and MeHgCl are essential for the protective effects of selenium against the MeHgCl-induced apoptosis, and the cytotoxicity, in RAW 264.7 cells, and may involve selenium-MeHgCl binding.

Diagnosis in Extension Injuries of the Lower Cervical Spine / 대한정형외과학회잡지

PURPOSE: The purpose of this study was to evaluate diagnostic criteria using plain lateral radiography, the incidence of traumatic disc herniation and the degree of neurologic deficit in extension injury of the lower cervical spine. MATERIALS AND METHODS: We analyzed 28 patients with extension injury of the lower cervical spine, by measuring the retropharyngeal, retrotracheal space and the intervertebral space at the injured level in plain lateral radiography. We selected 40 patients as a control group for the prevertebral soft tissue space measurement. RESULTS: Widening was found in the retropharyngeal space (6.8 +/-2.9 mm) and in the retrotracheal space (15.2 +/-3.8 mm) compared with the control group (4.2 +/-0.7 mm, 12.6 +/-1.9 mm, p<0.05). No significant increase in the injured intervertebral space was observed with respect to the normal upper and lower disc space. Neurologic deficit occurred in 25 cases (89%); with root injury in 11 cases and cord injury in 14 cases. There were 19 posterior disc herniations (68%), which were associated with neurologic deficits in all cases. CONCLUSION: Extension injuries should be suspected in the presence of soft tissue injury of the anterior column without fracture or dislocation by the radiologic study of the lower cervical spine. Magnetic resonance imaging study is believed to be an essential diagnostic modality for the accurate evaluation and proper management of the lower cervical spine injuries.

Effect of Glutathione on Apoptosis Induced by Methyl Mercury Chloride / 대한산업의학회지

OBJECTIVES: This study was performed to evaluate the critical role of glutathione(GSH) in methyl mercury chloride(MeHgCl)induced cell apoptosis. METHODS: The effect of GSH in MeHgCl induced cell apoptosis was observed in mouse macrophage-derived RAW 264.7 cells in vitro. The cells were cultured in Dulbecco's modified Eagle's medium(DMEM). RESULTS: MeHgCl exerted a dose dependent cytotoxicity,as demonstrated by the MTT assay, which is an assay dependent partially on the mitochondrial function. Moreover, in the presence of NAC, a GSH precursor, the MeHgCl induced cytotoxicity was significantly decreased whereas BSO, a specific GSH synthesis inhibitor,increased the MeHgCl induced cytotoxicity.The MeHgCl induced DNA fragmentation and chromatin condensation was consistent with the morphological alterations. The MeHgCl treated cells exhibited increasing annexin V-FITC binding to the phos-phatidylserine(PS)translocated from the inner to the outer leaflet of the plasma membrane and those cells with NAC pretreatment significantly exhibited decreasing annexin V-FITC binding compared to the cells treated with MeHgCl only. However BSO pretreatment markedly exhibited the increasing annexin V-FITC binding. The MeHgCl treated cells generated ROS, which was evidenced by the oxidation of dihydroethidine and the generation of the fluorescent product, ethidium. In addition, BSO pretreatment further enhanced the extent of ROS generation caused by MeHgCl whereas NAC pretreatment decreased the amount of ROS generation. MeHgCl led to a dose dependent decrease in the GSH content. Although MeHgCl exposure significantly reduced the GSH level, those cells that had a NAC pretreatment contained a higher level of GSH compared to the cells treated with MeHgCl only. In contrast, BSO pretreatment futher enhanced the extent of GSH depletion caused by MeHgCl. CONCLUSIONS: These results indicate that MeHgCl reduced the GSH content and impaired the defense against oxidative damage caused by ROS formation in RAW 264.7 cells. It is possible that these factors leads to the activation of the apoptosis signaling pathway. Ultimately these results suggest that GSH plays a crucial role in protecting the activity against MeHgCl induced apoptosis.

The Usefulness of 3D-Surface Rendering of the MRI in Surgical Treatment of Patients with Intractable Neocortical Epilepsy

BACKGROUND: This study is designed to indicate the role of 3D-surface rendering of the MRI in defining and resect-ing the epileptogenic zone. METHODS: 25 healthy volunteers and 55 patients were studied. Conventional MRI and 3D-surface rendering were performed. Sulcal and gyral patterns were assesed by a neuroradiologist and a neurologist with-out the clinical informations. Chronic video-EEG monitoring with surface and subdural grid electrodes, and PET were done. Resection was performed based on data of the EEG recordings and 3D-surface rendering. RESULTS: Conventional MRI identified structural abnormality ("MRI-identifiable lesion") in 20 patients. 20 of 35 patients without structural abnormality in conventional MRI revealed abnormal sulcal and gyral patterns in 3D-surface rendering of MRI ("3D-identifiable lesion"). Subdural grid EEGs recorded focal or diffuse ictal EEG onset from the region of "3D-identifiable lesion". Histopathologic findings revealed cortical dysplasia in 48 and neocortical gliosis in seven. Overall surgical out-come, at the average follow up period of 32.5 months, showed class I in 63.6%, class II in 25.5%, and class III in 10.9%. Among 20 patients with "MRI-identifiable lesion", 80% were in class I and 20% were in class II. Among 35 patients without "MRI-identifiable lesion", 54.3% were in class I, 28.6% were class II, and 17.1% were in class III. 80% of 20 patients with "3D-identifiable lesion" showed class I and 20% of 15 patients without "3D-identifiable lesion" showed class I. CONCLUSIONS: Identification of "MRI-identifiable lesion" or "3D-identifiable lesion" was of value in defining the epileptogenic zone. Resection of "MRI-identifiable lesion" or "3D-identifiable lesion", which were epilep-togenic in EEGs, promised a good surgical outcome.

A Study on the Protective Effects of Glutathione on Cytotoxicity of Mercury and Cadmium / 예방의학회지

OBJECTIVES: To evaluate the protective effects of glutathione (GSH) on the cytotoxicity of mercurial compounds(CH3HgCl, HgCl2) or cadmium chloride(CdCl2) in EMT-6 cells. METHODS: The compounds investigated were CH3HgCl, HgCl2, CdCl2, GSH, buthionine sulfoximine(BSO), L-2-oxothiazolidine-4-carboxylic acid(OTC). Cytotoxicity analysis consist of nitric oxide(NO) production, ATP production and cell viability. RESULTS: Mercurial compounds and cadmium chloride significantly decreased cell viability and the synthesis of NO and cellular ATP in EMT-6 cells. GSH was not toxic at concentrations of 0 - 1.6 mM. In the presence of GSH, mercurial compounds and cadmium did not decrease the production of ATP and nitrite in EMT-6 cells. The protective effects of GSH against the cytotoxicity of mercurial compounds and cadmium depended on the concentration of added GSH to the culture medium for EMT-6 cells. We evaluated the effects of intracellular GSH level on mercury- or cadmium-induced cytotoxicity by the pretreatment experiments. Pretreatment of GSH was not changed NO2- and ATP production, and pretreatment of BSO was decreased in dose- and time-dependent manner. Pretreatment of OTC was increased NO2- and ATP production in dose- and time-dependent manner. Because intracellular GSH level was increased by OTC pretreatment, the protective effect on mercury- and cadmium-induced cytotoxicity was increased. CONCLUSIONS: These results indicated that sulfhydryl compounds had the protective effects against mercury-induced cytotoxicity by the intracellular GSH levels.

Induction of Apoptosis by Heavy Metals in HL-60 Cells / 대한산업의학회지

OBJECTIVES: Apotosis induced by metals and metal-related deleterious conditions has only recently been studied. Although the toxic effects of heavy metal are well described, little is known about the mechanism of apoptosis by heavy metal toxicity. This study is designed to define the induction of apoptosis by which heavy metals exert the cytotoxic effect on human promyelocytic leukemic HL-60 cells. Methods After the incubation with CdC12, Na2SeO3 and HgC12, viability of the cells were measured by MTT assay. DNA fragmentation was analyzed by electrophoresis. For measurement of caspase 1 and 3-like proteases activity, the whole lysates were subjected to the proteolytic cleavage and then measured by using fluorospectrometry. c-JUN N-terminal kinase (JNK) activity was detected by an in vitro kinase assay. Transcriptional activities of activating protein-1 (AP-1) and nuclear factor-kB (NF-kB) were measured by elec trophoresis mobility shift assay (EMSA). RESULTS: Cadmium (l2OuiN/I) and selenium (30,iM) induce the apoptosis of HL-60 cells which is characterized by the ladder pattern of DNA fragmentation. Cadmium and selenium induce the activation of caspase-3 in a time dependent manner. They also increase the phosphotransferase activities of c-JUN N-terminal kinase (JNK) in cadmium and selenium treated HL-60 cells. Furthermore, cadmium and selenium increase the activation of transcriptional factors including AP-i and NF-kB. CONCLUSIONS: These results suggest that cadmium and selenium induce the apoptotic death of HL-60 cells via activation of DEVD-specific caspase, JNK and transcriptional factors such as AP-1 and NF-kB.

A Study of Protective Effect of Selenium Against Cytotoxicity of Methylmercury Chloride / 대한산업의학회지

The purpose of the present study was to elucidate the cytotoxical influence of mercurial compounds and the protective effect of selenium against mercurial compounds. The effects of mercury compounds and selenium on the syntheses of nitrite(NO2-) and ATP were observed in the cell cultures of EMT-6 cells and peritoneal macrophages from Balb/c mouse. The viabilities of EMT-6 cells and peritoneal macrophages at the end of culture were significantly decreased in dose-dependent manner by methylmercury chloride (CH3HgCl) added into the media. NO2- and ATP syntheses of the cells were dose-dependently inhibited by CH3HgCl. Simultaneous addition of the equimolar dose of selenium completely prevented mercury-induced inhibitions of NO2- and ATP syntheses, which were observed in both of EMT-6 cells and peritoneal macrophages. But these effects of selenium were not appeared in the new medium containing mercurials only which were removed the selenium after the pretreatment of selenium for 6 hours. These results suggest that protective effect of selenium against mercurial compounds was archived by the formation of a complex consisting of Se-Hg or Se-Hg-protein. Though its mechanism was not clear, the protective role of selemium against the mercury toxicity would be exhibited in the immunological system.

Cytotoxic Influence of Mercurial Compounds and the Protective Effect of Selenium in the EMT-6 Cells / 대한산업의학회지

No abstract available.

Effects of Mercury Chloride on Nitric Oxide Syntheses in Mouse Peritoneal Macrophage and EMT-6 Cell / 예방의학회지

The effects of treatment with mercury chloride on the nitrite and nitrate syntheses were observed in peritoneal macrophages from Balb/c mice and EMT-6 cells in vitro. The cells were cultured in Dulbecco's modified Eagle's medium(DMEM) with cytokines. Amounts of nitrite and nitrate in the culture media after 24 and 36 hours of culture were about 2-fold, and 3-fold of those measured after 12 hours respectively. There were very close associations between the amounts of nitrite and nitrate measured in the culture media according to culture time. The survival rate of peritoneal macrophages was significantly decreased by mercury chloride added into the media in dose-dependent manner, however the survivals of EMT-6 cells were not influenced by mercury chloride concentration in media. Nitrite and nitrate syntheses were dose-dependently decreased by mercury chloride added in culture media. ATP synthesis also decreased in EMT-6 cells by mercury chloride. These results reported here suggest that the disorder of cell mediated immunity by mercurials could be related to the inhibition of nitric oxide synthesis which seems to be caused by the inhibition of ATP synthesis.

NO2- and ATP synthesis in the EMT-6 cell stimulated by mercury chloride / 예방의학회지

Effect of Mercury chloride on the synthesis of NO2- and ATP were observed in EMT-6 cells which were culture with cytokines(IL-1alpha and IFN-gamma) and various concentrations of mercury chloride from 0.05 to 0.08 M. Viability of EMT-6 cells were observed above 90% in almost groups. There were not significant differences in the viability between mercury supplemented groups and control group. It suggests viability of EMT-6 cells were not influenced by these concentrations of mercury chloride. Results of the synthesis of nitrite showed significant time and group effect. There is a significant interaction effect between concentration of mercury chloride and culture time. The effect of various concentration of mercury chloride is not the same for all levels of culture time. There were significant differences in the synthesis of nitrite between mercury chloride supplemented groups and control group, and the synthesis of nitrite in EMT-6 cell by the supplement of mercury chloride was significantly decreased in a dose-dependent manner. Results of the synthesis of ATP showed a significant group effect, and the time main effect and the Group x Time interaction were also significant. There were significant differences in the synthesis of ATP between mercury chloride supplemented groups and control group, and the synthesis of ATP in EMT-6 cell by the supplement of mercury chloride was significantly decreased in a dose-dependent manner. These results suggest that the disorder of cell mediated immunity by mercury chloride could be related to the inhibition of nitric oxide synthesis which will be caused by the decreased synthesis of ATP.

A Study of Cytotoxical Mechanism of Mercurial Compounds in RAW264.7 Cell Line / 대한산업의학회지

The effects of glucose on the productions of ATP and nitrite which are inhibited by mercury compounds, were examined in a cell culture system of RAW 264.7 cells. The cells were cultured in Dulbecco's Modified Eagle's medium (DMEM) with cytokines, IL-1 and TNF for 24 hours. The viablility of RAW 264.7 cells at the end of culture was significantly decreased by mercury chloride or methylmercury chloride added into the media in dose-dependent manner, however the viability of RAW 264.7 cells were influenced in the concentrations lese than 0.8micrometer of mercury chloride or 0.4micrometer of methylmercury chloride. The addition of 4.5 g/l glucose to normal DMEM lowered the pH of media to the range of 6.7-6.8 after 48 hours of culture, but not for the cell survivals. This supplement of glucose to the media also prevented the inhibitions of ATP and nitrite syntheses which were caused by mercurial compounds. These results suggest that the disorder of cell mediated immunity by mercurials could be related to the inhibition of nitric oxide synthesis which seams to be caused by the inhibition of ATP synthesis, especially related to the citric acid cycle.

Effect of Mercury Chloride on Peritoneal Macrophage or EMT-6 cell from Balb/c mice / 대한산업의학회지

The effect of treatment of mercury chloride on the nitrite and nitrate synthesis was observed in peritoneal macrophages from Balb/c mice and EMT-6 cells in vitro. The cells were cultured in Dulbecco's modified Eagle's medium (DMEM) with cytokines. Amounts of nitrite and nitrate in the culture media after 24 and 36 hours of culture were about 2-fold, and 3-fold of those measured after 12 hours respectively. There were very close associations between the amounts of nitrite and nitrate measured in the culture media, according to culture time. The survival rate of peritoneal macrophages was significantly decreased by mercury chloride added into the media in dose-dependent manner, however the survivals of EMT-6 cells were not influenced by mercury chloride concentration in media. Nitrite and nitrate syntheses were dose-dependently decreased by mercury chloride added in culture media. These results reported here suggest that the disorder of cell mediated immunity by mercurials could be related to the inhibition of nitric oxide synthesis which seems to be caused by the inhibition of metabolism of cells.

Effect of Mercury Chloride on Peritoneal Macrophage or EMT-6 cell from Balb/c mice / 대한산업의학회지

The effect of treatment of mercury chloride on the nitrite and nitrate synthesis was observed in peritoneal macrophages from Balb/c mice and EMT-6 cells in vitro. The cells were cultured in Dulbecco's modified Eagle's medium (DMEM) with cytokines. Amounts of nitrite and nitrate in the culture media after 24 and 36 hours of culture were about 2-fold, and 3-fold of those measured after 12 hours respectively. There were very close associations between the amounts of nitrite and nitrate measured in the culture media, according to culture time. The survival rate of peritoneal macrophages was significantly decreased by mercury chloride added into the media in dose-dependent manner, however the survivals of EMT-6 cells were not influenced by mercury chloride concentration in media. Nitrite and nitrate syntheses were dose-dependently decreased by mercury chloride added in culture media. These results reported here suggest that the disorder of cell mediated immunity by mercurials could be related to the inhibition of nitric oxide synthesis which seems to be caused by the inhibition of metabolism of cells.

HgCl2 Dysregulates the Immune Response of Balb/c Mice / 예방의학회지

The studies reported here were undertaken to investigate the effects of mercury chloride on immune system of Balb/c mouse employing a flexible tier of in vitro and in vivo assays. Mercury chloride inhibited the proliferative responses of spleen cells to lipopolysaccharide, pokeweed mitogen, and phytohemagglutinin as a dose-dependent manner. This inhibitory effect was observed not only when HgCl2 was added 2nd or 3rd day of 3 days culture period but also when spleen cells was pretreated with HgC12 for 2 hours. Mercury chloride, however, potentiated the production of IgM and IgG from spleen cells. During the HgCl2 administration by drinking for 3 weeks, the weight gain of mice was significantly blunted than that of control group mice, while no overt signs related to mercury toxicity were noted in any mice of experimental group. There was no change in thymus and spleen weights, and in histological findings of kidney, bone marrow of femur, thymus, spleen, and politeful lymph node after 3 weeks of mercury exposure. However, HgC12 induced a significant increase of total serum IgM, IgG including IgG1, IgG2a and IgG2b, and IgE in Balb/c mice. Treatment in vivo with anti-IL-4 monoclonal antibody significantly abrogated the HgCl2-induced increase in total serum IgG1 and IgE. Whereas HgCl2 potentiated total serum IgM and IgG, there was, there was no difference in total serum hemagglutinin to SRBC(Sheep Red Blood cell) between experimental and control group mice when these mice were immunized with SRBC. All these findings observed in Balb/c mice suggest that mercury perturbates well-orchestrated regulation of immune responses before developing histopathological changes in lymphoid tissues.

A Study on Working Environment and Health Status of Workers in Some Dyeing Factories / 대한산업의학회지

This study was carried out to evaluated the actual conditions of working environment and health status of workers and search more effective health management method of workers in some dyeing factories. This study was conducted from April 1 to October 30, 1992, for 426 workers in two dyeing factories and an electric wire making factories. Among 324 workers in two dyeing factories, 57.5% were male and 42.5% were female. Most of the engaged workers had less than 2 years of working carrier and aged 30 years or below. The used chemical substances exceeding 1 ton per a month were sodium hydroxide(NaOH), hydrogen peroxide(H2O2), sodium chlorite(NaClO2), sodium sulfate(Ma2SO4), sodium carbonate(Na2CO3), and sodium hydrosulfite(Na2S2O4). The used chemical dyes exceeding 100kg per a month were suncion blue H-ERD, levafix brilliant red E-4BA, suncion yellow E-3G, and remazol black B. As the allowable exposure time by governmental threshold limit valuses to industrial noise levels in 90 dBA for 8 hours. Average noise levels of the individual plants were ranged from 75 to 95 dB (A). The TLV for total cotton dust in 2.0mg/m3. Average cotton-dust concentration in these working environmental air were ranging from 0.2-1.3mg/m3. The TLV chlorine, acetic acid and formic acid are 1 ppm, 10 ppm & 5ppm, respectively. The range of chlorine, and acetic and formic acid concentration in these working environmental air were detected 0.2-1.6 ppm and at trace level. The accident by chemical substances and dyes was not found on these working environment. From the physical examination and Todai Health Index scores results, there was no significant correlation between the used chemical substances and the diseases, such as bronchial asthma, other hyperreactive respiratory diseases and contact dermatitis. It was suggested that long term survey should be performed to detect the occupational health problem on these working environment.

Metallothionein induction and its protective effect in liver and kidney of rats exposed to cadmium chloride / 예방의학회지

Tolerance to several toxic effects of cadmium, including lethality has been shown following pretreatment with cadmium and zinc. This study was designed to determine if tolerance also develops to Cd-induced hepatotoxicity and renal toxicity. Three groups of rats (A, B, C), each consisting of 16 rats, were studied and each group was divided into four subgroups (1, 2, 3, 4), 4 rats for each subgroup. Rats were subcutaneously pretreated with saline (A), CdCl2(0.5 mg/kg, B), and ZnCl2 (13.0 mg/kg, C) during time periods of 1~6 weeks. At the end of the period, rats were challenged with CdCl2 (3.0, 6.0 and 9.0 mg/kg, ip). After giving the challenge dose, cadmium and metallothionein (MT) concentrations were determined and also observed the histologic change in liver and kidney. The concentration of cadmium in liver and also observed the increased dose-dependently to the challenge dosage. These data indicate the kidney is a major target organ of chronic cadmium poisoning, and suggest that cadmium induced hepatic injury, via release of Cd-MT, may play and important role in the nephrotoxicity observed in response to long-term exposure to cadmium. In addition, histologic examination of group A2, A3 and A4 revealed moderate to severe cadmium toxicity, evidenced by infiltration of inflammatory cells, cell swelling, pyknosis, enlarged sinusoids and necrosis in liver, and tubule cell necrosis and degeneration in kidney. However, MT concentrations in liver and kidney were increased by the pretreatment of CdCl2 and ZnCl2 and their morphological findings were not significantly changed, comparing with control group. Higher MT concentration in liver and kidney observed in the pretreated groups constitutes a plausible explanation of the protective effects of pretreatment against the cadmium toxicity after challenge dosing.

Selenium Effect on the Frequency of SCEs Induced by Heavy Metals in Human Lymphocytes / 예방의학회지

The protective effect of sodium selenite (Na2SeO3) against the cytogenetic toxicity of heavy metals was investigated on human whole-blood cultures in relation to induction of sister chromatid exchange(SCE) in secondary metaphase chromosome. Methlmercury chloride (CH3HgCl), cadmium chloride (CdCl2), Potassium dichromate (K2Cr2O7), and sodium selenite caused to the typically dose-dependent increase in sister chromatid exchanges (SCEs) by the concentrations ranging from 0.3 micro M to 10 micro M. However, the inductions of sister chromatid exchanges by methymercury chloride or cadmium chloride were inhibited by the simultaneous addition of sodium selenite 1.2 micro M. The frequencies of SCE were decreased to the level of control in the molar ratios as 2 : 1, 1 : 1, 1 : 2, and 1 : 4 of selenium selenite vs. methylmercury chloride, and as 1 : 1 and 1 : 2 of selenium selenite vs. cadmium chloride, while the frequencies of SCE induced by potassium dichromate were not changed by the addition of sodium selenite in culture condition. Mitotic indices were decreased in the higher concentrations of chemicals and not significantly changed by the simultaneous addition of sodium selenite to the culture condition containing each chemicals.

Effect of Several Heavy Metals on the Frequencies of Sister Chromatid Exchanges and Chromosomal Aberrations in Human Lymphocytes / 예방의학회지

To assay the cytogenetic toxicity of NiCl, K2Cr2O7CdC12, and HgC12, the frequencies of sister chromatid exchanges(SCEs) and chromosomal aberrations were observed in the metaphase chromosomes of the human lymphocytes which were cultured with above materials. The frequencies of SCEs are dose-dependently increased by all materials in this experiment. Chromosomal aberrations, especially gap and break, are increased by the nickel and chromic compounds, while not significantly increased by the cadmium and mercurial compounds. This results indicate the dose dependent relationship between the frequencies of SCEs and the concentrations of the heavy metals, but the increasing rates of the SCEs induced by the heavy metals are less sensitive than other mutagens or carcinogens which were confirmed.