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1.
The frequency of micronucleated cells (MNC) derived from exfoliated human oral mucosal cells has been measured to assess genotoxic damage in chewers of betel quid with tobacco (BQT) and tobacco with lime (T). Significantly elevated frequencies of MNC were observed in the exposed groups (BQT = 4.83 +/- 0.70; T = 5.20 +/- 0.66 per 1000 cells) compared to the control group (C = 2.59 +/- 0.37) although the levels observed were lower than those reported in the literature. No correlation was seen between age, duration and frequency of habits and the frequency of MNC in the 2 habit groups. Clastogenic agents in betel quid possibly involved in micronucleus formation are discussed.  相似文献   

2.
Among 61 patients undergoing maintenance peritoneal dialysis for an average of 20 months, 13 (21%) had a history of attacks of acute arthritis and 19 (31%) were found to have tender and often swollen joints. Deposits of calcium pyrophosphate dihydrate crystals in articular cartilage were identified in four patients and inflammation probably induced by hydroxyapatite crystals was noted in one. Periarticular calcification was observed in 12 patients and subperiosteal resorption of the phalanges in 20. The average calcium X phosphorus product was significantly higher (P < 0.025) in patients with a history of attacks of acute arthritis or with inflamed joints (58 +/- 12) than in those without (50 +/- 12). In the 19 patients whose treatment was changed to continuous ambulatory peritoneal dialysis there was a significant decrease (P < 0.025) in the calcium X phosphorus product but not in the proportion of patients with attacks of acute arthritis or with inflamed joints. The results indicate that articular complications are frequent among patients undergoing maintenance peritoneal dialysis and may be more common than with long-term hemodialysis.  相似文献   

3.
The health concerns have been raised following the enormous increase in the use of wireless mobile telephones throughout the world. This investigation had been taken, with the motive to find out whether mobile phone radiations cause any in vivo effects on the frequency of micronucleated exfoliated cells in the exposed subjects. A total of 109 subjects including 85 regular mobile phone users (exposed) and 24 non-users (controls) had participated in this study. Exfoliated cells were obtained by swabbing the buccal-mucosa from exposed as well as sex-age-matched controls. One thousand exfoliated cells were screened from each individual for nuclear anomalies including micronuclei (MN), karyolysis (KL), karyorrhexis (KH), broken egg (BE) and binucleated (BN) cells. The average daily duration of exposure to mobile phone radiations is 61.26 min with an overall average duration of exposure in term of years is 2.35 years in exposed subjects along with the 9.84+/-0.745 micronucleated cells (MNCs) and 10.72+/-0.889 total micronuclei (TMN) as compared to zero duration of exposure along with average 3.75+/-0.774 MNC and 4.00+/-0.808 TMN in controls. The means are significantly different in case of MNC and TMN at 0.01% level of significance. The mean of KL in controls is 13.17+/-2.750 and in exposed subjects is 13.06+/-1.793. The value of means of KH in exposed subjects (1.84+/-0.432) is slightly higher than in controls (1.42+/-0.737). Mean frequency of broken egg is found to be more in exposed subjects (0.65+/-0.276) as compared to controls (0.50+/-0.217). Frequency of presence of more than one nucleus in a cell (binucleated) is also higher in exposed (2.72+/-0.374) in comparison to controls (0.67+/-0.231). Although there is a slight increase in mean frequency of KH, BE and BN in exposed subjects but the difference is not found statistically significant. Correlation between 0-1, 1-2, 2-3 and 3-4 years of exposure and the frequency of MNC and TMN has been calculated and found to be positively correlated.  相似文献   

4.
Mice heterozygous for a p53 null mutation develop tumours induced by genotoxic carcinogens with a shorter latency than wild type mice and have been proposed as an alternate animal model for carcinogenicity testing. Some literature data suggest that p53+/- mice might also be more sensitive to the short-term effects of genotoxic agents and manifest a haploinsufficiency phenotype that could contribute to the higher tumour susceptibility. We have compared the induction of micronuclei in bone marrow and blood of p53+/- and p53+/+ isogenic mice after treatment with a single or multiple doses of melphalan (MLP), a crosslinking genotoxic carcinogen. We have also characterized the mechanism of micronucleus induction with CREST staining of kinetochore proteins to distinguish between chromosome break- and chromosome loss-induced micronuclei. Significant increases of micronucleated bone marrow polychromatic erythrocytes and blood reticulocytes were induced under all MLP exposure conditions. The frequency of micronucleated blood erythrocytes increased linearly with duration of exposure. Micronuclei were essentially a consequence of chromosome break events. After a single MLP dose, a significant reduction of the frequency of polychromatic erythrocytes in bone marrow of p53+/+ animals suggested the induction of cytotoxicity/cell cycle delay. This effect was not observed in p53+/- mice. We believe this finding to provide some evidence of a haploinsufficiency phenotype in the modulation of cell cycle/apoptotic pathways mediated by the p53 protein. In bone marrow of wild type mice, an increased effect of multiple MLP doses was detected over that of a single administration, whereas, in p53+/- mice, no differential effect was found of different exposure durations. Possibly, the probability of micronucleus formation increased under chronic exposure because of increased cell division in response to peripheral anemia and a reduction of p53 protein level had a small effect on cell cycle modulation and on such indirect mechanism of micronucleus induction. However, pairwise comparisons between the frequencies of cells with micronuclei in wild type and p53+/- mice under all exposure conditions did not show statistically significant differences, suggesting that the observed effects of p53 haploinsufficiency were weak and temporary and a higher/faster induction of irreversible chromosome damage could not account for the increased susceptibility of p53+/- mice to MLP-induced tumours.  相似文献   

5.
A major complication of continuous ambulatory peritoneal dialysis (CAPD) is peritonitis caused by Candida albicans. Increasing the activity of the peritoneal macrophages, the predominant cell type found in the peritoneal cavity, may be a promising treatment for this infection. Tuftsin was found to increase thioglycollate-elicited mouse peritoneal macrophage activity. 2x10(-7) M tuftsin enhanced two-fold cell association with radiolabelled candida, superoxide aniom production, and killing activity. Thus, a model consisting of mice undergoing peritoneal dialysis was developed in order to study the use of tuftsin as a therapeutic drug against peritoneal candidiasis. Administration of tuftsin (50 micrograms/mouse) before candidiasis induction with a lethal dose of candida (7x10(8) candida per mouse) improved mouse survival up to 70%, compared with 10% in the control group. The potential of tuftsin as a treatment for candidiasis was shown when the infection was induced with a sublethal dose of candida. Daily intraperitoneal injections of tuftsin (50 micrograms) to the sublethally infected mice caused a significant decrease in the number of candida recovered from the peritoneal cavity and from the blood (from 700 +/- 190 to 110 +/- 26 CFU/ml and from 100 +/- 26 CFU/ml to 17 +/- 8 CFU/ml, respectively). In addition, a larger number of peritoneal macrophages with greater phagocytic and killing activity were found in the tuftsin-treated mice. The effect of tuftsin may promote its potential use in the therapy of peritonitis in patients undergoing chronic peritoneal dialysis.  相似文献   

6.
In order to estimate the exposure levels of mutagenic and carcinogenic heterocyclic amines in humans, we developed a high-performance liquid chromatography method to detect 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) and 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) in dialysis fluid of patients with uremia. Using this methods, dialysis fluid of 12 patients who had received hemodialysis treatment or continuous ambulatory peritoneal dialysis was examined. Trp-P-1 was detected in dialysate of all uremic patients (727 +/- 282 pmoles, n = 12). In patients who had been treated with continuous ambulatory peritoneal dialysis, the average amount of Trp-P-1 found in whole dialysate (6 l) per day was 710 +/- 203 pmoles (mean +/- S.D., n = 8). Moreover, Trp-P-2 could be detected in 5 out of 12 patients (206 +/- 85 pmoles, n = 5). These results indicate that patients with uremia are actually exposed to carcinogenic tryptophan pyrolysis products. The average exposure level of Trp-P-1 in uremic patients apparently exceeded 710 pmoles (150 ng) per day.  相似文献   

7.
Ye X  Yan W  Xie H  Zhao M  Ying C 《Mutation research》2005,588(1):22-27
The evidence for genotoxic potential of formaldehyde (FA) in humans is insufficient and conflicting. We previously reported a higher frequency of micronuclei in nasal and oral exfoliative cells from students exposed to formaldehyde vapor for short-term. To further evaluate the genetic effects of long-term occupational exposure to FA and short-term exposure to FA of indoor sources, the frequencies of micronuclei (MN) in nasal mucosa cells, sister chromatid exchanges (SCEs) of peripheral lymphocytes, and the lymphocyte subsets were evaluated in 18 non-smoking workers (mean exposure duration was 8.6 years) in an FA factory and 16 non-smoking waiters exposed to FA for 12 weeks in a ballroom. A non-smoking student group without occupational exposure (n=23) to FA was used as control. The 8h time-weighted average (TWA) concentrations of formaldehyde was 0.985+/-0.286 mg/m3 with the ceiling exposure concentration of 1.694 mg/m3 in the workshop, and 0.107+/-0.067 mg/m3 in the ballroom (5 h TWA). Higher frequencies of micronuclei per thousand cells in nasal mucosa cells of workers versus control (2.70+/-1.50 versus 1.25+/-0.65, p<0.05) and higher frequency of SCEs in peripheral lymphocytes of workers group (8.24+/-0.89 versus 6.38+/-0.41, p<0.05) were observed. Increased frequency of micronuclei in nasal mucosa cells or SCE in peripheral lymphocytes was not found among waiters group. The results suggest that the genotoxic potential of high level FA exposure may have occupational risks in long-term exposure groups.  相似文献   

8.
9.
The aim of this study was to evaluate the genotoxic effect of low dose of occupational radiation exposure in Nuclear Medicine Department employees, by using cytokinesis-blocked micronucleus assay in peripheral blood lymphocytes. The study included 46 exposed individuals together with 27 from the same area without occupational exposure to radiation which served as controls. The results obtained were evaluated with respect to age, gender, smoking habits, pathological condition and the occupational exposure to radiation of the individuals. The frequency of micronuclei increased significantly with the age of the subjects (P = 0.007). However there were no significant differences in micronucleus frequency with gender, smoking habits and occupational exposure. The frequency of micronuclei was significantly higher in individuals with presence of pathological condition (P < 0.0001) in comparison to healthy population irrespective of their exposure status.  相似文献   

10.
Understanding the risks deriving from protracted exposure to low doses of ionizing radiation has remarkable societal importance in view of the large number of work settings in which sources of IR are encountered. To address this question, we studied the frequency of micronuclei (MN), which is an indicator of DNA damage, in a population exposed to low levels of ionizing radiation and in matched controls. In both exposed population and controls, the possible influence of single nucleotide polymorphisms in XRCC1, XRCC3 and XPD genes on the frequency of micronuclei was also evaluated. We also considered the effects of confounding factors, like smoking status, age and gender. The results indicated that MN frequency was significantly higher in the exposed workers than in the controls [8.62+/-2.80 versus 6.86+/-2.65; P=0.019]. Radiological workers with variant alleles for XRCC1 or XRCC3 polymorphisms or wild-type alleles for XPD exon 23 or 10 polymorphisms showed a significantly higher MN frequency than controls with the same genotypes. Smoking status did not affect micronuclei frequency either in exposed workers or controls, while age was associated with increased MN frequency in the exposed only. In the combined population, gender but not age exerted an influence on the yield of MN, being higher in females than in males. Even though there is a limitation in this study due to the small number of subjects, these results suggest that even exposures to low level of ionizing radiation could have genotoxic effects and that XRCC3, XRCC1 and XPD polymorphisms might contribute to the increased genetic damage in susceptible individuals occupationally exposed to chronic low levels of ionizing radiation. For a clear conclusion on the induction of DNA damage caused by protracted exposure to low doses of ionizing radiation and the possible influence of genetic polymorphism in DNA repair genes larger studies are needed.  相似文献   

11.
OBJECTIVE: It is known that glucose concentrations of peritoneal dialysis solutions are detrimental to the peritoneal membrane. In order to determine the effect of glucose concentration on cytokine levels of peritoneal fluid of continuous ambulatory peritoneal dialysis (CAPD) patients, a cross-sectional study was performed. METHODS: Nine non-diabetic CAPD patients participated in two 8-h dwell sessions of overnight exchanges in consecutive days, with 1.36% and 3.86% glucose containing peritoneal dialysis solutions (Baxter-Eczacibas). Peritoneal dialysis fluid tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 levels were measured. RESULTS: TNF-alpha levels after 1.36% and 3.86% glucose used dwells were 23+/-14 pg/ml and 28+/-4 pg/ml, respectively (p=0.78). The IL-6 levels were 106+/-57 pg/ml and 115+/-63 pg/ml (p=0.81), respectively. CONCLUSION: In our in vivo study we found that the glucose concentration of the conventional lactate-based CAPD solution has no effect on basal IL-6 and TNF-alpha levels of peritoneal fluid. Further in vivo studies with non-lactate-based CAPD solutions are needed in order to determine the effect of glucose concentration per se on cytokine release.  相似文献   

12.
The phagocytic activity and bactericidal capacity of polymorphonuclear neutrophils (PMN) were evaluated in patients with advanced chronic renal failure. The studies were made in patients undergoing hemodialysis, maintenance peritoneal dialysis as well as in nondialysed patients. Evaluations were carried out by using of the recently described fluorochrome microassay which enabled these parameters to be estimate independently. The phagocytic activity was seriously diminished in nondialysed patients, whereas it was similar to controls in those hemodialysed and undergoing peritoneal dialysis patients. In all evaluated groups of patients the bactericidal capacity was significantly reduced. The lowest values could always be observed in nondialysed patients. The decrease of bactericidal capacity was significantly more evident in patients undergoing peritoneal dialysis as compared with those hemodialysed. The obtained results confirm some previous reports suggesting the impairment of PMN function in uremic patients. This results in their increased susceptibility to infection. They also reveal the existence of a close relationship between the extent of observed dysfunctions and the management applied.  相似文献   

13.
目的:分析和比较血液透析和腹膜透析终末期肾病患者预后的影响及其安全性。方法:选取2010年1月至2016年4月本医院收治的透析患者246例作为研究对象,将其分为血液透析组和腹膜透析组,比较两组患者治疗后的生存情况及并发症的发生情况。结果:两组患者死亡原因是心力衰竭、消化道出血、重度感染、脑梗死,两组的病死率及死因构成比较差异均无统计学意义(P0.05)。腹膜透析组患者1年、3年、5年生存率均显著高于血液透析组(P0.05),两组患者7年生存率比较差异无统计学意义(P0.05)。首次透析年龄超过60岁的终末期肾病患者中,腹膜透析组1年、3年、5年、7年生存率均显著低于血液透析组(P0.05)。血液透析组心力衰竭、动静脉内瘘闭塞发生率显著高于腹膜透析组(P0.05),腹膜透析组腹膜炎的发生率显著高于血液透析组(P0.05),血液透析组总并发症发生率明显高于腹膜透析组(P0.05)。结论:血液透析和腹膜透析各有优缺点,对终末期肾病患者应个体化选择透析方式,减少并发症,提高生活质量及生存率。  相似文献   

14.
Aim of this work was to assess the predictive value of micronuclei (MN) frequency in peripheral blood lymphocytes (PBL) for the risk of cancer death in disease-free individuals. Blood samples from 1650 subjects selected from the general population of Pisa, Italy, were collected between June 1991 and November 1993. The follow-up until January 2005 recorded a total of 111 deaths (52 for cancer). MN frequency was assessed for 49 cancer cases and 101 matched controls. A significantly higher MN frequency was found in cancer cases (4.7+/-3.4 MN/1000 BN cells) versus controls (1.5+/-1.7; p<0.0001). Donors were stratified in two classes and multivariate logistic regression analysis confirmed that individuals with high MN frequency (>2.5 MN/1000 BN cells) had a significantly increased risk of cancer death (OR=10.7; 95% CI=4.6-24.9; p<0.0001) when compared to individuals with low MN frequency (相似文献   

15.
Pesticides are widely used throughout the world in agriculture to protect crops and in public health to control diseases. Nevertheless exposure to pesticides can represent a potential risk to humans. Pesticide manufacturing unit workers are prone to possible occupational pesticide exposure. Therefore, this study was performed to evaluate the genotoxic effect of pesticide exposure in these workers. In the present investigation 54 pesticide workers and an equal number of control subjects were assessed for genome damage in blood lymphocytes utilizing the chromosomal aberration analysis and the buccal epithelial cell by adopting the micronucleus test. The results suggested that pesticide workers had a significantly increased frequency of chromosomal aberrations when compared with controls (mean+/-S.D., 8.43+/-2.36 versus 3.32+/-1.26; P<0.05). Similarly, the pesticides exposed workers showed a significant increase in micronucleated cells compared with controls (1.24+/-0.72 versus 0.32+/-0.26; P<0.05). Analysis of variance revealed that occupational exposure to pesticides had a significant effect on frequency of micronuclei (P<0.05), whereas smoking, age, gender and alcohol consumption had no significant effect on genetic damage (P>0.05). However, no association was found between years of exposure, smoking, age, gender, alcohol consumption and higher levels of genetic damage as assessed by the chromosomal aberration assay (P>0.05). Our findings indicate that occupational exposure to pesticides could cause genome damage in somatic cells.  相似文献   

16.
Plasma fatty acid profiles from maintenance hemodialysis patients (n = 9) were compared with those from healthy volunteers (n = 9). Hemodialysis patients had significantly higher levels of oleic acid, 15.3 +/- 1.1 vs. 8.9 +/- 0.6% (p less than 0.0001), and lower levels of arachidonic acid (6.0 +/- 0.5 vs. 8.4 +/- 0.3%, p less than 0.0009). Linolenic and linoleic acids, the essential fatty acid and precursors of arachidonic acid, were also significantly lower than normal in the dialysis group. These data show that dialysis patients have fatty acid abnormalities suggesting relative depletion of essential fatty acids. These observations are important because these abnormalities may play an important role in the pathogenesis of some common clinical conditions associated with uremia, such as a constellation of skin problems, fragility of erythrocytes, lipid anomalies and hormonal aberrations.  相似文献   

17.
Skin autofluorescence (SAF) measurement is a simple, noninvasive method to assess tissue advanced glycation end products (AGE). In patients with end-stage renal disease and in those on hemodialysis AGE production is increased. Less is known about those treated with peritoneal dialysis (PD). In this study we tested if SAF is influenced by clinical and treatment characteristics in PD patients.This cross-sectional study included 198 PD patients (of those, 128 were on traditional glucose-based solutions and 70 patients were partially switched to icodextrin-based PD). SAF measurements were done with a specific AGE Reader device. The impact of patients' age, gender, current diabetes, duration of PD, cumulative glucose exposure, body mass index, smoking habits and use of icodextrin on SAF values were tested with multiple regression analysis.Our analysis revealed that patients' age, current diabetes and icodextrin use significantly increase patients' SAF values (p = 0.015, 0.012, 0.005, respectively). AGE exposure of PD patients with diabetes and on icodextrin solution is increased. Further investigation is required whether this finding is due to the icodextrin itself or for a still unspecified clinical characteristic of PD population treated with icodextrin.  相似文献   

18.
The mitotic cell-cycle duration of root meristematic cells of Eichhornia crassipes as determined by the colchicine labelling method was approximately 24 h at 30 +/- 1 degrees C. In one experiment the intact root meristems of E. crassipes were subjected to 1 h acute exposure to water contaminated with maleic hydrazide (MH), 56 ppm, or methyl mercuric chloride (MMCl), 0.1-0.5 ppm, followed by recovery in tap water for 4-48 h. In a second experiment the roots were subjected to 96 h exposure to water contaminated with MH, 56 ppm, or MMCl, 0.0001-0.1 ppm. In both experiments the cytological end-point measured was the frequency of cells with micronuclei (MNC). In the first experiment, while in the MH-exposed root meristems the frequency of MNC was significant at 40 h of recovery, MMCl induced significant MNC at 12, 20, 24, 40, and 40 h of recovery depending on the concentration. In the second experiment both test chemicals induced MNC which was concentration-dependent in case of MMCl. The highest ineffective concentration tested (HICT) and lowest effective concentration tested (LECT) for MMC determined in this experiment were 0.0005 ppm and 0.001 ppm, respectively. The present work provides evidence that E. crassipes could be a promising in situ environmental biomonitoring assay system.  相似文献   

19.
Chronic obstructive pulmonary disease (COPD) is a condition characterized by chronic airway inflammation and remodeling, lung parenchymal inflammation, and destruction resulting in expiratory airflow obstruction, hyperinflation of the lung with loss of elastic recoil, and impairment of gas exchange. Skeletal muscles in individuals with COPD generate free radicals at rest, and production increases during contractile activity. Overproduction of free radicals may result in oxidant-antioxidant imbalance in favor of oxidants. This study evaluated the levels of genetic damage in peripheral blood of patients with COPD using the cytokinesis-blocked micronucleus (CBMN) and the comet assays. The study was conducted with 25 patients with COPD and 25 controls matched for age and sex. Results of both comet and CBMN assays showed an increase in the level of DNA damage. In the group of patients with COPD, the mean frequency of binucleate cells with micronuclei was 6.72+/-3.02, and in the control group, 4.20+/-2.08 (p=0.00233). Mean comet value was 26.84+/-19.61 in patients with COPD and 7.25+/-7.57 in the control group (p=0.00004). The increased frequency of micronuclei in patients with COPD was primarily assigned to clastogenic events and DNA amplification because the frequency of nucleoplasmic bridges and buds was also increased. Oxidative stress in lung cells is a constant source of free radicals that damage genetic material of both lung and circulating cells.  相似文献   

20.
摘要 目的:探讨高通量血液透析对糖尿病肾病(DN)血液透析患者心脏功能及结构的影响,并分析预后的影响因素。方法:选取2017年5月~2018年11月期间我院收治的DN血液透析患者(n=172),上述DN血液透析患者中普通透析治疗者60例(普通透析组)、高通量血液透析治疗者112例(高通量透析组)。普通透析组采用低通量透析治疗,高通量透析组采用高通量透析治疗,比较两组患者心脏功能及结构以及预后情况,采用单因素、多因素Logistic回归分析预后的影响因素。结果:高通量透析组治疗6个月后左心房内径(LAD)、左心室舒张末内径(LVDd)、左心室心肌重量指数(LVMI)低于治疗前和普通透析组(P<0.05),高通量透析组治疗6个月后左心室射血分数( LVEF )高于治疗前和普通透析组(P<0.05)。高通量透析组的生存率高于普通透析组(P<0.05)。存活组年龄、上机前舒张压、上机前收缩压、血磷、全段甲状旁腺激素(iPTH)均低于死亡组(P<0.05),存活组透析频率、白蛋白、血红蛋白均高于死亡组(P<0.05),两组性别、血钙比较无差异(P>0.05)。多因素Logistic回归分析结果显示,上机前舒张压高、上机前收缩压高、血磷高、iPTH高、透析频率少、白蛋白低、血红蛋白低均是DN血液透析患者死亡的危险因素(P<0.05)。结论:高通量血液透析能减轻DN患者血液透析所引起的心脏功能及结构损伤,改善患者预后。影响DN血液透析患者预后的因素较多,其中上机前舒张压、上机前收缩压、血磷、iPTH越高,白蛋白、血红蛋白越低,透析频率越少,患者的死亡风险越大。  相似文献   

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