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Whereas the stress-inducible heat-shock protein 70 (Hsp70) has gained plenty of attention as a putative target for tumor therapy, little is known about the role of other Hsp70 proteins in cancer. Here we present the first thorough analysis of the expression and function of the cytosolic Hsp70 proteins in human cancer cells and identify Hsp70-2, a protein essential for spermatogenesis, as an important regulator of cancer cell growth. Targeted knock-down of the individual family members by RNA interference revealed that both Hsp70 and Hsp70-2 were required for cancer cell growth, whereas the survival of tumorigenic as well as nontumorigenic cells depended on Hsc70. Cancer cells depleted for Hsp70 and Hsp70-2 displayed strikingly different morphologies (detached and round vs. flat senescent-like), cell cycle distributions (G2/M vs. G1 arrest) and gene expression profiles. Only Hsp70-2 depletion induced the expression of macrophage inhibitory cytokine-1 that was identified as a target of P53 tumor-suppressor protein and a mediator of the G1 arrest and the senescent phenotype. Importantly, concomitant depletion of Hsp70 and Hsp70-2 had a synergistic antiproliferative effect on cancer cells. Thus, highly homologous Hsp70 proteins bring about nonoverlapping functions essential for cell growth and survival.  相似文献   
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Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has become a powerful and widespread analytical tool in all fields of life science. Compared with other techniques, its high accuracy and sensitivity makes it a superior method, especially for the analysis of nucleic acids. Recent problems in the analysis of nucleic acids by MALDI-TOF MS can be solved using an automated MALDI-compatible sample-preparation system. Together with the reliable minisequencing assay, high-throughput genotyping of single nucleotide polymorphisms by MALDI-TOF MS is able to become a routine method in research, clinical genetics and diagnostics.  相似文献   
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AimImproving survival for women with early breast cancer (eBC) requires greater attention to the consequences of treatment, including risk to ovarian function. We have assessed whether biochemical markers of the ovarian reserve might improve prediction of chemotherapy related amenorrhoea.MethodsWomen (n = 59, mean age 42.6 years [(range 23.3–52.5]) with eBC were recruited before any treatment. Pretreatment ovarian reserve markers (anti-Müllerian hormone [AMH], follicle-stimulating hormone [FSH], inhibin B) were analysed in relation to ovarian status at 2 years.ResultsPretreatment AMH was significantly lower in women with amenorrhoea at 2 years (4.0 ± 0.9 pmol/L versus 17.2 ± 2.5, P < 0.0001), but FSH and inhibin B did not differ between groups. By logistic regression, pretreatment AMH, but not age, FSH or inhibin B, was an independent predictor of ovarian status at 2 years (P = 0.005; odds ratio 0.013). We combined these data with a similar cohort (combined n = 75); receiver–operator characteristic analysis for AMH gave area under curve (AUC) of 0.90 (95% confidence interval (CI) 0.82–0.97)). A cross-validated classification tree analysis resulted in a binary classification schema with sensitivity 98.2% and specificity 80.0% for correct classification of amenorrhoea.ConclusionPretreatment AMH is a useful predictor of long term post chemotherapy loss of ovarian function in women with eBC, adding significantly to the only previously established individualising predictor, i.e. age. AMH measurement may assist decision-making regarding treatment options and fertility preservation procedures.  相似文献   
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The committee was charged with determining whether healing of erosions in rheumatoid arthritis (RA) occurs. Two exercises were performed: The first asked the committee members, as a panel of experts, to express agreement or disagreement with the presence of improvement and features of bone reaction to injury in images submitted by members as examples of healing. The second presented panel members with 28 pairs of serial images, 14 chosen to illustrate progression and 14 chosen to illustrate repair. Agreement was tested on 8 items: global judgment on which image in the pair was better, relative size of the erosion in the 2 images, judgment on which image was first, presence and extent of sclerosis, cortication, filling-in, remodeling, and reconstituting normal structure. Our results showed good agreement, among the 15 respondents, on global assessment of which image was better and which image showed the smaller erosion. Correct assignment of sequence was only slightly better than expected by chance (in 65% of the cases). Agreement was poor regarding the presence of morphologic features of bone repair. A majority of a panel of experts agreed on which 2nd images in a set of paired, serial images represented improvement and which showed progression based on global assessment of which was better and on size of erosion. Features of bone repair were not distinctive and did not enable the panel to deduce the correct sequence of the serial images. This study provides evidence that repair of bone damage in RA does occur, resulting in some degree of improvement, which was recognized by a majority of a panel of experts.  相似文献   
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BackgroundIt is not known what diagnoses are associated with an elevated D-dimer in unselected patients attending emergency departments (ED), nor have their associated outcomes been determined.MethodsThis was a prospective observational study of 1612 unselected patients attending a Danish ED, with 100% follow-up for 90 days after presentation.ResultsThe 765 (47%) ED patients with an elevated D-dimer level (ie, ≥ 0.5 mg/L) were more likely to be admitted to hospital (P <.0001), re-present to health services (P = .02), and die within 90 days (8.1% of patients, P <.0001). Only 10 patients with a normal D-dimer level (1.2%) died within 90 days. Five had chronic obstructive pulmonary disease and infection, and 5 had cancer (4 of whom also had infection). Venous thromboembolism, infection, neoplasia, anemia, heart failure, and unspecified soft tissue disorders were significantly associated with an elevated D-dimer level. Of the 72 patients with venous thromboembolism, 20 also had infection, 8 had cancer, and 4 had anemia. None of the patients with heart failure, stroke, or acute myocardial infarction with a normal D-dimer level died within 90 days.ConclusionsIn this study, nearly half of all patients attending the ED had an elevated D-dimer level, and these patients were more likely to be admitted to hospital and to re-present to health services or die within 90 days. In this unselected ED patient population, elevated D-dimer levels were found to not only be significantly associated with venous thromboembolism, but to also be associated with infection, cancer, heart failure, and anemia.  相似文献   
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