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31.
The subchronic (14–18 wk) toxicity of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), a mutagenic by-product in chlorinated drinking water, was evaluated in Wistar rats. In a range-finding study, MX was administered daily for 14 days by gavage in deionized water to male rats (five animals per group) at doses of 12.5, 25, 50, 100 or 200 mg/kg body weight. The doses above 50 mg/kg were lethal and three out of five animals also died during treatment at 50 mg/kg. The range-finding study was repeated with doses of 5, 10 and 20 mg MX/kg, given on 5 days a week, to both males and females (10 animals per group). These doses were not overtly toxic but caused several changes in plasma clinical chemistry at 10 and 20 mg MX/kg in comparison with the controls. These included increased urea, creatinine and bilirubin and decreased inorganic phosphate and potassium in females and increased cholesterol in males. In the subchronic toxicity study, rats (15 per group) were given MX by gavage, on 5 days a week, at doses of 0 (controls) or 30 mg/kg (low dose) for 18 wk, or, in the high-dose group, at doses increasing from 45 to 75 mg/kg over 14 wk. The high dose was finally lethal (two males and one female died) and caused hypersalivation, wheezing respiration, emaciation and tangled fur in animals. The body weights of the high-dose males decreased by 15%, and food consumption was decreased by 15 to 20%, but the water consumption increased by 15% to 60%. Plasma cholesterol and triglycerides were elevated and urine excretion was increased. Urine specific gravity was decreased and the relative weights of the liver and kidneys were increased in both sexes at both doses in comparison with the controls. At both doses, duodenal hyperplasia occurred in males and females, and slight focal epithelial hyperplasia in the forestomach was observed in males. Splenic atrophy and haemosiderosis were seen in two high-dose females, and epithelial cell atypia in the urinary bladder of one high-dose male and female. The frequency of bone marrow polychromatic erythrocytes with micronuclei was slightly increased in low-dose males. The results indicate that repeated administration of MX disturbs the fluid-electrolyte balance and induces diuresis, causes mucosal hyperplasia in the gastro-intestinal tract as a local effect, and affects lipid metabolism.  相似文献   
32.
Abstract: The effects of dichloromethylene bisphosphonate (clodronate) on the composition of bone mineral, morphology and histology of a long bone with an artificial femoral fracture were studied in a 22 week experiment. Two hundred twenty-four female rats were allocated to dose groups of 0, 3, 10, and 30 mg/kg clodronate daily subcutaneously. Bone calcium, phosphorus and magnesium concentrations remained stable and fluoride concentration rose with time. There were no statistical differences between different groups. Clodronate did not alter the histology of the callus nor delayed the healing of the fracture. It caused mild to moderate prominence of the metaphyseal area in the fractured bone in a dose- and time-dependent manner. Serum osteocalcin levels were lowered in the treated animals dose-dependently. Other serological as well as haematological values were within normal range. Clodronate seems in this experimental arrangement to be a safe agent to administer in different pathological conditions of bone even when they are complicated by fractures of long bones.  相似文献   
33.
Clinical features, 8 histological variables, 7 nuclear morphometric variables, 2 mitotic indices, oestrogen-receptor (ER) and progesterone-receptor content (PR), DNA ploidy and S-phase fraction (SPF) were entered in a Cox's model to assess their independent predictive value in 216 breast-cancer patients followed up for over 9 years. In the whole series, histological type (p = 0.007), volume-corrected mitotic index (M/V index) (p = 0.01), axillary-lymph-node (pN) status (p = 0.024) and the year of treatment (p = 0.045) predicted independently the recurrence-free survival (RFS). In a sub-analysis including SPF (n = 148), the year of treatment (p = 0.003), tumour diameter (p = 0.004), SPF (p = 0.022) and nuclear pleomorphism (p = 0.056) independently predicted the RFS. In a Cox's analysis of the whole series, tumour diameter (p less than 0.001), pN status (p = 0.001), PR status (p = 0.002) and the year of treatment (p = 0.021) were independent predictors of survival. In a separate analysis including also SPF (n = 148), tumour diameter (p less than 0.001), SPF (p = 0.003), pN status (p = 0.008) and the year of treatment (p = 0.015) proved to be independent prognostic factors. The results show that tumour diameter, pN status, M/V-index, histological type, SPF and PR status comprise a sufficient combination of prognostic factors in female breast cancer. In pN patients, age and SDPE may be of additional prognostic significance. The prognostic scores combining the independent prognostic variables reflecting both the proliferative rate and metastatic potential of the tumours are accurate predictors of the RFS and overall survival.  相似文献   
34.
DNA ploidy, S-phase fraction (SPF), mitotic index (MI), volume corrected mitotic index (M/V index) and standard prognostic factors were related to disease outcome in a series of 363 women with breast cancer followed-up for over 10 years in our clinic. DNA ploidy and SPF were significantly related to histological type, tumour grade and mitotic indices (p < 0.001). In univariate survival analysis, pN status (p < 0.0001), tumour diameter (p < 0.0001), MI (p = 0.001), M/V index (p = 0.0003) and SPF (p = 0.015) predicted survival. In pN(-) tumours. MI (p = 0.059) was related to survival. In pN(+) tumours, tumour diameter (p = 0.0004), M/V index (p = 0.023) and SPF (p = 0.045) predicted survival. In multivariate survival analysis, tumour diameter (p < 0.001). M/V index (p < 0.007), pN status (p = 0.014) and patient age (p = 0.09) were independently related to survival. In pN(-) tumours, tumour diameter independently predicted survival (p = 0.033). In pN(+) tumours, tumour diameter (p < 0.001), M/V index (p = 0.006) and the year of treatment (p = 0.08) were independent predictors. The results show that tumour diameter, pN status and proliferative activity of cancer cells are important prognostic factors in breast cancer. Of the proliferation indices, M/V index and SPF are equally powerful predictors, and the use of M/V index is advocated due to simplicity of the assessment.  相似文献   
35.
The potential of nuclear morphometry and volume-corrected mitotic index (M/V index) in grading cases of transitional cell carcinoma of the urinary bladder was studied. 30 cases of bladder cancer including all three WHO grades were evaluated. Four investigators selected independently the most atypical field from paraffin sections, and one investigator measured the nuclear areas from these fields using the IBAS 1&2 image analyzer system. Following the same sampling rule, four investigators counted the mitotic figures per area of neoplastic tissue in the microscopic image at an objective magnification of X40. The mean nuclear areas covered values from 28.1 to 139.0 microns 2 (mean +/- SD 57.2 +/- 18.9). The total variance of measurements was 359.1 and the mean variance between corresponding fields 110.2 (about 30% of the total variation). The efficiency was evaluated by estimating the fraction of falsely classified cases. Instrumental morphometry of nuclear area in a three-grade system gave an efficiency of 79% and of 90%, in a two-grade system. The M/V index varied from 0 to 54 (mean +/- SD 12.3 +/- 10.9). The total variance was 119.8 and the methodological variance 15.5 (about 13% of total variance). In a three-grade system this would correspond to an efficiency of about 75%; in a two-grade system the efficiency would be 88%. The results suggest that nuclear area and M/V index estimates constitute efficient grading systems in bladder carcinoma.  相似文献   
36.
SULT1A1 is involved in biotransformation of many endogenous and exogenous substrates, such as drugs, hormones and tobacco smoke carcinogens. A polymorphism in the sulfotransferase 1A1 gene (SULT1A1) results in an amino acid change from Arg to His at codon 213. The His allele (SULT1A1*2) has been shown to encode a protein with much lower catalytic activity than the protein encoded by the Arg allele (SULT1A1*1). We examined whether this polymorphism modified breast cancer risk in a Finnish-Caucasian study population consisting of 483 breast cancer patients and 482 healthy population controls. No significant genotype effects were seen in the overall breast cancer risk. However, a decreased risk of breast cancer was found among premenopausal women with at least three pregnancies and at least one SULT1A1*2 allele (odds ratio = 0.23, 95% confidence interval = 0.09-0.63) compared to women with two SULT1A1*1 alleles. Our results suggest that the SULT1A1 genotype is not an important risk factor for breast cancer in general, but may modify the risk among premenopausaul women with high parity.  相似文献   
37.
We investigated the dose and time dependency of inflammatory and cytotoxic responses to size-segregated urban air particulate samples in the mouse lung. Coarse (PM10-2.5), fine (PM2.5-0.2), and ultrafine (PM0.2) particles were collected in six European cities (Duisburg, Prague, Amsterdam, Helsinki, Barcelona, Athens) in selected seasons using a modified Harvard high-volume cascade impactor. Healthy C57Bl/6J mice were intratracheally exposed to the particulate samples in a 24-h dose-response study (1, 3, and 10 mg/kg) and in 4-, 12-, and 24-h time course studies (10 mg/kg). After the exposures, the lungs were lavaged and the bronchoalveolar lavage fluid (BALF) was assayed for indicators of inflammation and tissue damage: total cell number, cell differential, total protein, and lactate dehydrogenase (LDH) and cytokine (tumor necrosis alpha [TNF-alpha], interleukin-6 [IL-6], and keratinocyte-derived chemokine [KC]) concentrations. In general, PM10-2.5 samples had higher inflammatory activity than PM2.5-0.2 samples. PM0.2 samples showed negligible inflammatory activity. PM10-2.5 and PM2.5-0.2 samples caused large increases in BALF cytokine concentrations at 4 h, but not at 12 or 24 h, after exposure. The BALF total cell number and total protein concentrations increased significantly at 12 h for both the PM10-2.5 and PM2.5-0.2 samples, but only PM10-2.5 samples produced consistent, significant increases at 24 h after exposure. There was more heterogeneity in BALF cytokine and neutrophil cell number responses to PM2.5-0.2 samples than to PM10-2.5 samples between the sampling campaigns. Thus, particle size, sources, and atmospheric transformation processes affect the inflammatory activity and response duration of urban air particulate matter in the mouse lung.  相似文献   
38.
OBJECTIVE: Coeliac disease (CD) is a common disease with a strong heredity. About 10-20% of 1st-degree relatives of probands develop CD. Relatives should be screened for CD, because if not treated, CD exposes patients to numerous complications. The heterogeneity of symptoms and the lifetime-spanning risk of CD render the timing of CD antibody and/or gastroscopy screenings difficult. As CD susceptibility has been shown to be strongly associated with the HLA alleles DQA1*0501 and DQB1*0201 (together encoding the DQ2 heterodimer) and DRB1*04 (associated with the DQ8 heterodimer), our aim was to investigate whether HLA genotyping might be useful in the identification of 1st-degree relatives of CD patients who do not need further screening for CD. MATERIAL AND METHODS: The study comprised 54 Finnish CD families including 54 CD probands and 382 living 1st-degree relatives. All subjects who were willing to participate were screened for CD (duodenal and skin biopsies; endomysial, reticulin and gliadin antibodies). The DQA1*0501, DQB1*0201 and DRB1*04 allele frequencies of CD patients and the 1st-degree relatives were determined. RESULTS: Altogether 17.6% (5.9% of the parents, 15.7% of the siblings, 25.8% of the offspring) of the investigated 1st-degree relatives (n = 245) did not carry any of the alleles studied. All of the CD patients (n = 136) with the exception of one (0.7%) carried at least one of the alleles investigated. CONCLUSIONS: By using the HLA genotyping a considerable proportion of 1st-degree relatives of CD probands could be excluded from further screening for CD.  相似文献   
39.
OBJECTIVE: Coeliac disease (CD) susceptibility has been shown to be associated with the HLA alleles DQA1*0501 and DQB1*0201. This HLA-associated risk has been estimated to account for 29-40% of the genetic component of CD. Conflicting data have been published on the gene dose effect of these HLA alleles on the risk and severity of CD. In this study the aim was to investigate the association between the number of HLA risk alleles and the severity of CD. MATERIAL AND METHODS: Fifty-four Finnish CD families, including 144 CD patients mainly diagnosed in adulthood (94.4%), were enrolled in the study. The association between the number of DQA1*0501 and DQB1*0201 alleles and villous atrophy, symptoms and laboratory parameters at the time of diagnosis, and the association with villous atrophy after one year of treatment on a gluten-free diet were studied. RESULTS: The homozygosity for the DQB1*0201 allele was associated with a more severe form of CD assessed by more severe villous atrophy (p=0.011), younger age (p=0.036), more severe diarrhoea (p=0.048) and a lower level of blood haemoglobin at the time of diagnosis (p=0.010). Furthermore, the homozygosity for the DQB1*0201 allele was associated with a slower recovery of villous atrophy after a gluten-free diet (p=0.041). In contrast, the DQA1*0501 allele did not have a significant association with the severity of CD. CONCLUSIONS: Our results demonstrate a gene dose effect of the DQB1*0201 allele on the clinical heterogeneity of CD and on the rate of recovery from villous atrophy in patients on a gluten-free diet.  相似文献   
40.
Objective. There is evidence for the long-term safety of oats as part of a gluten-free diet in coeliac disease (CD). Oats is generally processed by kilning, which theoretically may change its antigenic properties and be the reason that it is tolerated by patients with CD. The aim of this study was to investigate the suitability of large amounts of unkilned oats, comparing its use with kilned oats in adult coeliac patients. Material and methods. The study group included 13 men and 19 women with CD in remission. The goal of daily intake of oats was 100 g during one year. These patients using oats as part of their gluten-free diet were randomized to two treatment groups. One group used regular oats and the other unkilned oats. After 6 months the patients changed the treatment groups. Food intake, symptoms, histology of the small intestine and the levels of endomysial antibodies were noted. Results. No marked changes were found in the duodenal biopsies, in the levels of endomysial antibodies or in the well-being of the patients. Compliance with the diet did not change during the follow-up. Conclusions. Large amounts of both unkilned and regular kilned oats are well tolerated by adult patients with CD. Oats is therefore not harmful, even in its unkilned form, which indicates that its antigenic nature is not changed by common industrial food processing in such a way that would prevent the provoking of CD.  相似文献   
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