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61.
The determination of age is an important step in defining the life history traits of individuals and populations. Age determination of odontocetes is mainly based on counting annual growth layer groups in the teeth. However, this useful method is always invasive, requiring the cutting of at least one tooth, and sometimes the results are difficult to interpret. Based on the concept that bone matrix is constantly deposited throughout life, we analysed the bone mineral density of the arm and forearm of a series of bottlenose dolphins (Tursiops truncatus, Montagu 1821) stranded along the Italian coast of the Adriatic Sea or maintained in confined waters. The bone mineral density values we obtained were evaluated as possible age predictors of the Mediterranean population of this species, considering age as determined by counting growth layer groups in sections of the teeth and the total body length of the animal as references. Comparisons between left and right flipper showed no difference. Our results show that bone mineral density values of the thoracic limb are indeed reliable age predictors in Tursiops truncatus. Further investigations in additional odontocete species are necessary to provide strong evidence of the reliability of bone mineral density as an indicator of growth and chronological wear and tear in toothed-whales.  相似文献   
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Iron-oxide nanoparticles (NPs) generated by environmental events are likely to represent health problems. α-Fe2O3 NPs were synthesized, characterized and tested in a model for toxicity utilizing human whole blood without added anticoagulant. MALDI-TOF of the corona was performed and activation markers for plasma cascade systems (complement, contact and coagulation systems), platelet consumption and release of growth factors, MPO, and chemokine/cytokines from blood cells were analyzed. The coronas formed on the pristine α-Fe2O3 NPs contained contact system proteins and they induced massive activation of the contact (kinin/kallikrein) system, as well as thrombin generation, platelet activation, and release of two pro-angiogeneic growth factors: platelet-derived growth factor and vascular endothelial growth factor, whereas complement activation was unaffected. The α-Fe2O3 NPs exhibited a noticeable toxicity, with kinin/kallikrein activation, which may be associated with hypotension and long-term angiogenesis in vivo, with implications for cancer, arteriosclerosis and pulmonary disease.  相似文献   
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Exposure to p-phenylenediamine (pPD), a primary intermediate in hair dye formulations, is often associated with the development of allergic contact dermatitis. Such reactions involve activation of the subject's immune system. The aim of these studies was to explore the relationship between pPD oxidation and functional maturation of human monocyte-derived dendritic cells in vitro. Dendritic cells were incubated with pPD and Bandrowski's base (BB) for 16 h, and expression of the costimulatory receptors CD40, CD80, CD83, CD86, and major histocompatibility complex class II intracellular glutathione levels and cell viability were measured. In certain experiments, glutathione (1 mM) was added to culture medium. Liquid chromatography-mass spectrometry (LC-MS) analysis and exhaustive solvent extraction were used to monitor the rate of [(14)C]pPD oxidation and the extent of pPD binding to cellular and serum protein, respectively. Proliferation of allogeneic lymphocytes was determined by incorporation of [(3)H]thymidine. Exposure of dendritic cells to pPD (5-50 microM), but not BB, was associated with an increase in CD40 and MHC class II expression and proliferation of allogeneic lymphocytes. Dendritic cell activation with pPD was not associated with apoptotic or necrotic cell death or depletion of glutathione. Neither pPD nor BB altered dendritic cell expression of CD80, CD83, or CD86. LC-MS analysis revealed pPD was rapidly oxidized in cell culture media to BB. Addition of glutathione inhibited BB formation but did not prevent covalent binding of pPD to dendritic cell protein or dendritic cell activation. Collectively, these studies show that pPD, but not BB, selectively activates human dendritic cells in vitro.  相似文献   
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Background

Recent studies have suggested that stent-grafting may improve the treatment outcome of patients with esophageal perforation, but evidence on this is still lacking.

Methods

Data on 194 patients who underwent conservative (43 patients), endoclip (4 patients) stent-grafting (63 patients) or surgical treatment (84 patients) for esophageal perforation were retrieved from nine medical centers.

Results

In-hospital/30-day mortality was 17.5 %. Three-year survival was 67.1 %. Age, coronary artery disease, and esophageal malignancy were independent predictors of early mortality. Chi squared automatic interaction detection analysis showed that patients without coronary artery disease, without esophageal malignancy and younger than 70 years had the lowest early mortality (4.1 %). Surgery was associated with slightly lower early mortality (conservative 23.3, endoclips 25.0 %, stent-grafting 19.0 %, surgery 13.1 %; p = 0.499). One center reported a series of more than 20 patients treated with stent-grafting which achieved an early mortality of 7.7 % (2/26 patients). Stent-grafting was associated with better survival with salvaged esophagus (conservative 76.7 %, endoclips 75.0 %, stent-grafting 77.8 %, surgery 56.0 %; p = 0.019). Propensity score adjusted analysis showed that stent-grafting achieved similar early mortality (p = 0.946), but significantly higher survival with salvaged esophagus than with surgical treatment (p = 0.001, OR 0.253, 95 % CI 0.110–0.585). Primary surgical repair was associated with somewhat lower early mortality (14.6 vs. 19.0 %; p = 0.561) and better survival with salvaged esophagus (85.4 vs. 77.8 %; p = 0.337) than stent-grafting.

Conclusions

Esophageal perforation was associated with a rather high mortality rate in this all-comers population. Stent-grafting failed to decrease operative mortality, but it improved survival with salvaged esophagus. The results of one of the centers indicate that increasing experience with this less invasive procedure may possibly improve the outcome of these patients.  相似文献   
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