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991.
992.
In 2005, cancer accounted for 13% of all deaths worldwide. Breast cancer is the number-one cause of cancer-related death among women in the USA, affecting 178,480 of them in 2007. As 75% of tumors in postmenopausal women and half in premenopausal women express estrogen receptor, endocrine therapy plays a significant role as a systemic treatment. Robust datasets have demonstrated the impact of tamoxifen in reducing breast cancer recurrence and mortality, regardless of the age of the patient. Other estrogen-deprivation strategies, such as aromatase inhibitors in postmenopausal women and luteinizing hormone-releasing hormone agonists in premenopausal women, are being increasingly used for estrogen receptor-positive breast cancer. This review discusses basic principles regarding endocrine therapy, the need for accurate estrogen receptor testing and the role of menopause in therapy selection.  相似文献   
993.
The expression of the classic steroid receptors ERalpha and PR-A has been correlated with stage, histological grade and survival in endometrial cancer. Endometrial cancer samples (293) were immunohistochemically analysed with monoclonal antibodies against the four steroid receptors. The loss of ERalpha, PR-A and PR-B resulted in a poorer survival in endometrial cancer patients, while ERbeta expression did not demonstrate any correlations with several analysed clinicopathological characteristics and did not affect survival. Additionally, multivariate survival analysis demonstrated that PR-B was a significant independent prognostic factor for cause-specific survival. In contrast, although ERalpha and PR-A showed a significant association between different endometrial histological subtypes and grading, both receptors were not independent factors with survival in endometrial carcinoma patients. Therefore, the PR-B immunostaining might be used as an easy, simple and highly efficient marker to identify high-risk patients and may aid in the selection of patients for a more aggressive adjuvant therapy.  相似文献   
994.
Nonrandom, reciprocal translocations between nonhomologous chromosomes are critical cellular events that lead to malignant transformation. Therefore, understanding the mechanisms involved in these chromosomal rearrangements is essential for understanding the process of carcinogenesis. There has been substantial discussion in the literature over the past 10 years about mechanisms involved in constitutional chromosomal rearrangements, including deletions, duplications, and translocations. Yet our understanding of the mechanisms of chromosomal rearrangements in cancer is still developing. This review presents what is known about the mechanisms involved in selected nonrandom chromosomal translocations in leukemia.  相似文献   
995.

Background

Non-alcoholic fatty liver disease (NAFLD) represents a major disease burden in the population. While the bidirectional association between NAFLD and diabetes is established, little is known about the association of hepatic iron content and glycaemia. Moreover, analyses of sex-specific effects and of dynamic changes in glycaemia are scarce.

Methods

We investigated 7-year sex-specific trajectories of glycaemia and related traits (HbA1c, fasting glucose, fasting insulin, HOMA-IR, 2-h glucose and cross-sectional 2-h insulin) in a sample from a population-based cohort (N = 365; 41.1% female). Hepatic iron and fat content were assessed by 3T-Magnetic Resonance Imaging (MRI). Two-step multi-level models adjusted for glucose-lowering medication and confounders were applied.

Results

In women and men, markers of glucose metabolism correlated with hepatic iron and fat content. Deterioration of glycaemia was associated with increased hepatic iron content in men (normoglycaemia to prediabetes: beta = 2.21 s−1, 95% CI [0.47, 3.95]). Additionally, deterioration of glycaemia (e.g. prediabetes to diabetes: 1.27 log(%), [0.84, 1.70]) and trajectories of glucose, insulin and HOMA-IR were significantly associated with hepatic fat content in men. Similarly, deterioration of glycaemia as well as trajectories of glucose, insulin and HOMA-IR was significantly associated with increased hepatic fat content in women (e.g. trajectory of fasting insulin: 0.63 log(%), [0.36, 0.90]).

Conclusions

Unfavourable 7-year trajectories of markers of glucose metabolism are associated with increased hepatic fat content, particularly in women, whereas the association with hepatic iron content was less clear. Monitoring changes of glycaemia in the sub-diabetic range might enable early identification of hepatic iron overload and steatosis.  相似文献   
996.
The recently identified bacterium Tannerella serpentiformis is the closest phylogenetic relative of Tannerella forsythia, whose presence in oral biofilms is associated with periodontitis. Conversely, T. serpentiformis is considered health-associated. This discrepancy was investigated in a comparative study of the two Tannerella species. The biofilm behavior was analyzed upon their addition and of Porphyromonas gingivalis—each bacterium separately or in combinations—to an in vitro five-species oral model biofilm. Biofilm composition and architecture was analyzed quantitatively using real-time PCR and qualitatively by fluorescence in situ hybridization/confocal laser scanning microscopy, and by scanning electron microscopy. The presence of T. serpentiformis led to a decrease of the total cell number of biofilm bacteria, while P. gingivalis was growth-promoting. This effect was mitigated by T. serpentiformis when added to the biofilm together with P. gingivalis. Notably, T. serpentiformis outcompeted T. forsythia numbers when the two species were simultaneously added to the biofilm compared to biofilms containing T. forsythia alone. Tannerella serpentiformis appeared evenly distributed throughout the multispecies biofilm, while T. forsythia was surface-located. Adhesion and invasion assays revealed that T. serpentiformis was significantly less effective in invading human gingival epithelial cells than T. forsythia. Furthermore, compared to T. forsythia, a higher immunostimulatory potential of human gingival fibroblasts and macrophages was revealed for T. serpentiformis, based on mRNA expression levels of the inflammatory mediators interleukin 6 (IL-6), IL-8, monocyte chemoattractant protein-1 and tumor necrosis factor α, and production of the corresponding proteins. Collectively, these data support the potential of T. serpentiformis to interfere with biological processes relevant to the establishment of periodontitis.  相似文献   
997.
We report a case of photoallergic contact dermatitis to two sunscreen agents, methoxycinnamate and oxybenzone, occurring in a 6-year-old Asian boy.  相似文献   
998.
999.
1000.
Tumor cells that show downregulation of their tumor-associated antigens (TAAs) may be able to escape immune-mediated elimination. Therefore, efficient vaccine strategies attempt to target multiple TAAs simultaneously. This is easily achieved in dendritic cell (DC)-based vaccines by introducing antigens in the form of RNA. Although insufficient message may hinder adequate expression of individual TAAs when using total-tumor RNA, high amounts of individual RNAs as pools yield DCs presenting high numbers of specific peptide-major histocompatibility complex ligands with epitopes derived from different TAAs. We used the transfer of RNAs encoding the well-defined melanoma TAAs tyrosinase, Melan-A, CDK4mut, gp100, SNRP116mut, and GPNMBmut to characterize DCs at the levels of transfected RNA, expressed protein and peptide-major histocompatibility complex ligand presentation. TAA-encoding RNA was rapidly degraded in the DCs, allowing only a single surge in protein expression shortly after transfection. We compared the functional capacity of DCs transfected with pools of 3 versus 6 RNAs. Whereas functional assays demonstrated a decrease in stimulatory capacity of DCs transfected with a pool of 3 RNAs by only 30% as compared with single RNAs, a 60% loss was seen with 6 RNAs. We conclude that larger RNA pools result in diminished presentation of individual epitopes and suggest that smaller pools of RNA be transfected into separate DC populations which are then pooled to create multiplex vaccines.  相似文献   
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