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41.
The ataxia-telangiectasia-mutated (ATM) kinase is a key transducer of DNA damage signals within the genome maintenance machinery and a tumour suppressor whose germline mutations predispose to familial breast cancer. ATM signalling is constitutively activated in early stages of diverse types of human malignancies and cell culture models in response to oncogene-induced DNA damage providing a barrier against tumour progression. As BRCA1 and BRCA2 are also components of the genome maintenance network and their mutations predispose to breast cancer, we have examined the ATM expression in human breast carcinomas of BRCA1/2 mutation carriers, sporadic cases and familial non-BRCA1/2 patients. Our results show that ATM protein expression is aberrantly reduced more frequently among BRCA1 (33%; P=0.0003) and BRCA2 (30%; P=0.0009) tumours than in non-BRCA1/2 tumours (10.7%). Furthermore, the non-BRCA1/2 tumours with reduced ATM expression were more often estrogen receptor (ER) negative (P=0.0002), progesterone receptor (PR) negative (P=0.004) and were of higher grade (P=0.0004). In our series of 1013 non-BRCA1/2 cases, ATM was more commonly deficient (20%; P=0.0006) and p53 was overabundant (47%; P<0.0000000001) among the difficult-to-treat ER/PR/ERBB2-triple-negative subset of tumours compared with cases that expressed at least one of these receptors (10 and 16% of aberrant ATM and p53, respectively). We propose a model of 'conditional haploinsufficiency' for BRCA1/2 under conditions of enhanced DNA damage in precancerous lesions resulting in more robust activation and hence increased selection for inactivation or loss of ATM in tumours of BRCA1/2 mutation carriers, with implications for genomic instability and curability of diverse subsets of human breast cancer.  相似文献   
42.
Mulibrey nanism is an autosomal recessive disease with severe growth failure and multiple organ involvement. Heart manifestations include constrictive pericarditis and restrictive cardiomyopathy. The purpose of this study was to evaluate left ventricular (LV) diastolic and systolic function in children with mulibrey nanism utilizing two- and three- dimensional (2-D and 3-D) echocardiography and measurement of serum levels of natriuretic peptides. Of the 30 children diagnosed with mulibrey nanism in Finland, 26 participated. The control group comprised 26 children. In 2-D echocardiography, the interventricular septum and LV posterior wall were thicker in patients. The left atrium/aorta ratio measured a median 1.8 (range, 1.4–2.5) in patients and 1.3 (range, 1.0–1.7) in controls (p < 0.001). Patients differed from controls in several indices of diastolic LV function. In 3-D echocardiography, LV end diastolic volume measured a median of 51.9 ml/m2 (range, 33.3–73.4) in patients and 59.7 ml/m2 (range, 37.6–87.6) in controls (p = 0.040), and serum levels of N-terminal proatriopeptide and N-terminal pro-brain natriuretic peptide measured, respectively, a median of 0.54 nmol/L (range, 0.04–4.7) and 289 ng/L (range, 18–9170) in patients and 0.28 nmol/L (range, 0.09–0.72; p < 0.001) and 54 ng/L (range, 26–139; p < 0.001) in controls. They correlated with several indices of diastolic LV function. In a significant proportion of children with mulibrey nanism, myocardial function is impaired. Significant correlations appeared between indices of LV function, size of the left atrium, and levels of natriuretic peptides, showing that measurement of serum levels of natriuretic peptides is a useful follow-up method despite its dependence on loading conditions.  相似文献   
43.
Reports on the prognosis of familial breast cancer patients have been contradictory. True differences in survival, if they exist, would have important implications for genetic counselling and in treatment of hereditary breast cancer. We assessed the survival rates of 359 familial breast cancer patients (32 patients from BRCA1-positive families, 43 patients from BRCA2-positive families and 284 patients from BRCA1/2-negative breast cancer families) and compared them with those of all other breast cancer patients diagnosed in Finland from 1953 to 1995 (n = 59,517). Cumulative relative survival rates (RSR) were calculated by dividing the observed survival rates by the expected ones. The expected survival rates were derived from the sex, age and calendar year specific life-tables of the general population in Finland. Regression model was used to calculate relative excess risk of death (RR) and to adjust for confounding factors. The overall 5-year RSR of the patients in the BRCA1 families, BRCA2 families, non-BRCA1/2 families and among sporadic cases was 67%, 77%, 86% and 78%, respectively. However, we found no significant differences in the RR adjusted for age, stage and year of diagnosis between the different familial patient groups or the general breast cancer population. In the BRCA1 families the RR tended to be higher [RR 1.30, 95% confidence interval (CI) 0.63--2.70] and in the BRCA2 families lower (RR 0.78, 95% CI 0.39--1.57) than among the general breast cancer patient population. The RR among patients in the non-BRCA1/2 families did not differ from that of the general patient population.  相似文献   
44.
Seventy-seven consecutive hypotensive (mean arterial pressure (MAP) less than 80 mmHg) surgical emergency patients were resuscitated according to either physicians' individual orders (38 patients) or an algorithm (39 patients). The shock was mainly caused by accidental injuries or acute gastrointestinal bleeding. The patients of the algorithm group were given more plasma expanders than the patients of the control group, while the total amount of fluids administered was similar in both groups. The primary goal of the resuscitation (MAP greater than 80 mmHg) was reached within 30 min in three cases in the control group and in seven cases in the algorithm group. The treatment times at the emergency department and the intensive care unit were similar for the groups. The number of severe and moderate pulmonary disturbances was the same, but mild disturbances were significantly more common in the control group. Renal failure was somewhat more common in the control group and the renal function disturbances were significantly more severe among the control patients. The results suggest that the physicians in some extent altered their practices in fluid resuscitation when the algorithm was put to use, and that this change, perhaps, produced the somewhat better outcome of the patients. The authors recommend the algorithm to be used as a basis of shock treatment and particularly in those emergency departments where the resuscitation of hypotensive patients is performed by junior or inexperienced physicians.  相似文献   
45.
PURPOSE: The p53 R72P polymorphism has been suggested to play a role in many cancers, including breast cancer. Our aim was to evaluate association of R72P with breast cancer risk as well as histopathologic features of the breast tumors and survival. EXPERIMENTAL DESIGN: The germ line R72P genotype was defined among 939 Finnish familial and 888 unselected breast cancer patients and 736 healthy population controls. The clinical and biological variables were tested for association by univariate analysis and the effects of several variables on survival by Cox's proportional hazards regression model. RESULTS: The distribution of the genotypes was similar in all groups studied, suggesting no association with breast cancer risk. Unselected breast cancer patients with 72P homozygous genotype presented significantly more often with lobular carcinoma, whereas R72 allele carriers had a significantly higher frequency of ductal carcinomas (P = 0.004). No significant association with other histopathologic variables, like tumor grade, hormone receptor status (estrogen and progesterone receptors), or tumor-node-metastasis stage, was observed. Survival analysis showed that unselected breast cancer patients with 72P homozygous genotype had significantly poorer survival than patients with other genotypes (P = 0.003). This effect on survival was independent of p53 expression in the tumors and multivariate analysis showed that 72P homozygous genotype was overall an independent prognostic factor (risk ratio of death, 2.1; 95% confidence interval, 1.4-3.3; P = 0.001). CONCLUSIONS: These results suggest no effect of either R72P allele on breast cancer risk but a significantly reduced survival for 72P homozygous breast cancer patients. The finding of codon 72 genotype as an independent prognostic marker for breast cancer warrants further studies.  相似文献   
46.
Nuclear DNA content and its prognostic value in lymphoma of the stomach   总被引:1,自引:0,他引:1  
H Joensuu  K O S?derstr?m  P J Klemi  E Eerola 《Cancer》1987,60(12):3042-3048
Nuclear DNA content of 27 primary lymphomas of the stomach was determined by flow cytometry from paraffin-embedded tissue. Thirteen (50%) of the 26 non-Hodgkin's lymphomas were aneuploid. The only case with Hodgkin's disease was diploid. The mean age of patients with aneuploid lymphoma was less than that of patients with diploid lymphoma (53 years versus 63 years, P = 0.02). DNA aneuploidy was more common in tumors with extragastric spread into the adjacent organs or the upper abdominal lymph nodes than in intragastric lymphomas (73% versus 17%; P = 0.003). Patients with aneuploid lymphoma had both inferior crude recurrence-free survival rate (P = 0.05) and survival rate corrected for known intercurrent diseases (P = 0.02) than patients with diploid lymphoma. Extragastric spread of lymphoma into the adjacent organs or the upper abdominal lymph nodes was, however, the most important prognostic factor by a multivariate analysis.  相似文献   
47.
We have recently shown that synovial fibroblasts cultured from patients with reactive or rheumatoid arthritis exhibit increased autofluorescence when compared with controls. Morphological studies suggested that this increase was related to the anomalous structure of mitochondria in cells cultured from rheumatoid or non-rheumatoid inflammatory synovial tissue. The present study describes attempts to find an explanation for these observations. The effects of conditioned media of cultured mononuclear cells were tested on normal synovial fibroblasts. Conditioned media of monocytes stimulated with lipopolysaccharide or poly-IC induced an increase in the cellular autofluorescence and changes in the morphology of mitochondria in normal fibroblasts. These changes were indistinguishable from those seen in synovial fibroblasts cultured from various arthritides. Indomethacin or gold salts did not abolish the effects of monocyte-conditioned media. Abnormal mitochondria could not be induced in the presence of cycloheximide. This study describes a new aspect of monocyte-fibroblast interactions during rheumatoid and non-rheumatoid inflammation of synovial tissue.  相似文献   
48.
The prevention of congenital rubella syndrome (CRS), as a complication of rubella infection during pregnancy, is the main aim of rubella vaccination programmes. However, as vaccination of infants leads to an increase in the average age at which those who were not immunized become infected, certain rubella vaccination programmes can lead to an increase in the incidence of CRS. In this paper we use a mathematical model of the transmission dynamics of rubella virus to investigate the likely impact of different vaccination policies in Europe. The model was able to capture pre- and post-vaccination patterns of infection and prevalence of serological markers under a wide variety of scenarios, suggesting that the model structure and parameter estimates were appropriate. Analytical and numerical results suggest that endemic circulation of rubella is unlikely in Finland, the United Kingdom, The Netherlands, and perhaps Denmark, provided vaccine coverage is uniform across geographical and social groups. In Italy and Germany vaccine coverage in infancy has not been sufficient to interrupt rubella transmission, and continued epidemics of CRS seem probable. It seems unlikely that the immunization programmes in these countries are doing more harm than good, but this may be partly as a result of selective immunization of schoolgirls. Indeed, in both these countries, selective vaccination of schoolgirls with inadequate vaccination histories is likely to be an important mechanism by which CRS incidence is suppressed (unlike the other countries, which have had sufficiently high infant coverage rates to withdraw this option). Reducing inequalities in the uptake of rubella vaccine may bring greater health benefits than increasing the mean level of coverage.  相似文献   
49.
The effect of dietary therapy with a human Lactobacillus strain GG (ATCC 53103), bovine colostrum, or bovine immune colostrum with specific antibodies against anaerobic intestinal bacteria on gut defence mechanisms were studied in juvenile chronic arthritis. Thirty patients with juvenile chronic arthritis were randomly allocated to receive a freeze-dried powder of Lactobacillus GG, or bovine colostrum, or bovine immune colostrum, for a two-week period. Immunologic and non-immunologic gut defence mechanisms were indirectly investigated in blood and faecal samples. In patients receiving Lactobacillus GG, the median (interquartile range) frequency of immunoglobulin-secreting cells, determined by enzyme-linked immunospot assay, increased in the IgA class from 1840 (690–2530) to 3480 (1030–13 170)/106 cells; p=0.02. Likewise the median (interquartile range) frequency of specific antibody-secreting cells against dietary antigens increased during the Lactobacillus GG therapy in the IgM class from 3.8 (1.4–5.0) to 11.2 (5.0–30.0)/106 cells; p=0.02. In addition, Lactobacillus GG therapy decreased the median (interquartile range) activity of faecal urease, which has been associated with mucosal tissue damage, from 40.3 (21.7–54.3) to 28.6 (24.5–49.4) nmol. min−1 (mg protein)−1; p=0.10, while, in patients receiving bovine colostrum, faecal urease activity increased (from 42.2 to 80.6; p=0.04). All findings were transient. We suggest that gut defence mechanisms are disturbed in juvenile chronic arthritis and we further suggest that orally administered Lactobacillus GG has a potential to reinforce the mucosal barrier mechanisms in juvenile chronic arthritis.  相似文献   
50.
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