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The opportunistic pathogen Staphylococcus aureus is one of the major causes of health care-associated infections. S. aureus is primarily an extracellular pathogen, but it was recently reported to invade and replicate in several host cell types. The ability of S. aureus to persist within cells has been implicated in resistance to antimicrobials and recurrent infections. However, few staphylococcal proteins that mediate intracellular survival have been identified. Here we examine if EsxA and EsxB, substrates of the ESAT-6-like secretion system (Ess), are important during intracellular S. aureus infection. The Esx proteins are required for staphylococcal virulence, but their functions during infection are unclear. While isogenic S. aureus esxA and esxB mutants were not defective for epithelial cell invasion in vitro, a significant increase in early/late apoptosis was observed in esxA mutant-infected cells compared to wild-type-infected cells. Impeding secretion of EsxA by deleting C-terminal residues of the protein also resulted in a significant increase of epithelial cell apoptosis. Furthermore, cells transfected with esxA showed an increased protection from apoptotic cell death. A double mutant lacking both EsxA and EsxB also induced increased apoptosis but, remarkably, was unable to escape from cells as efficiently as the single mutants or the wild type. Thus, using in vitro models of intracellular staphylococcal infection, we demonstrate that EsxA interferes with host cell apoptotic pathways and, together with EsxB, mediates the release of S. aureus from the host cell.  相似文献   
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The measurement of transepidermal water loss (TEWL) is important for evaluating the integrity of the barrier function of the stratum corneum. Normal TEWL values in healthy adults and in children ages 2 and older are well known, but few studies have been performed in infants and neonates. TEWL in healthy neonates younger than 24 hours old was assessed and compared with that of an adult study population. We also studied possible correlations between this parameter, gestational age, and mode of delivery. A prospective study was conducted in healthy newborns. The areas tested were the volar forearm and the popliteal fossa. Ninety‐nine healthy newborns were enrolled and 33 healthy adults were analyzed as controls. Statistically significant differences were noted between newborns and adults in TEWL (p < 0.01). Newborns had a much higher mean TEWL than adults. Differences in the morphology and physiology between newborn and mature skin can explain the higher TEWL in newborns. Higher TEWL could also be due to the sudden functional adaptation of the skin immediately after delivery, when the newborn transits from a liquid to the dry, gaseous extrauterine environment. Functional evaluation of the neonatal skin barrier is important mainly because maintaining skin integrity facilitates cutaneous adaptation.  相似文献   
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This research explores the family configurations of young adults with intellectual disability. Based on a sample of 40 individuals interviewed two times in a year, we found as many as four types of family configurations, with distinct compositions, and different types of social capital. This diversity is not without consequences for individual psychological adjustment. The results are discussed in the light of the configurational approach to families.  相似文献   
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This randomized phase III clinical trial explored the efficacy of DaunoXome (DNX) versus Daunorubicin (DNR) in acute myeloid leukaemia (AML) patients aged >60 years. Three hundred and one AML patients were randomized to receive DNR (45 mg/m(2) days 1-3) or DNX (80 mg/m(2) days 1-3) plus cytarabine (AraC; 100 mg/m(2) days 1-7). Patients in complete remission (CR) received a course of the same drugs as consolidation and then were randomized for maintenance with AraC+ all trans retinoic acid or no further treatment. Among 153 patients in the DNR arm, 78 (51.0%) achieved CR, 55 (35.9%) were resistant and 20 (13.1%) died during induction. Among 148 patients in the DNX arm, 73 (49.3%) achieved CR, 47 (31.8%) were resistant and 28 (18.9%) died during induction. Univariate analysis showed no difference as to induction results. After CR, DNX showed a higher incidence of early deaths (12.5% vs. 2.6% at 6 months, P = 0.053) but a lower incidence of relapse beyond 6 months (59% vs. 78% at 24 months, P = 0.064), with a cross in overall survival (OS) and disease-free survival (DFS) curves and a later advantage for DNX arm after 12 months from diagnosis. DNX seems to improve OS and DFS in the long-term follow-up, because of a reduction in late relapses.  相似文献   
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Rearrangements of the RET receptor tyrosine kinase gene generating RET/PTC oncogenes are specific to papillary thyroid carcinoma (PTC), the most frequent thyroid tumor. Here, we show that the RET/PTC1 oncogene, when exogenously expressed in primary normal human thyrocytes, induces the expression of a large set of genes involved in inflammation and tumor invasion, including those encoding chemokines (CCL2, CCL20, CXCL8, and CXCL12), chemokine receptors (CXCR4), cytokines (IL1B, CSF-1, GM-CSF, and G-CSF), matrix-degrading enzymes (metalloproteases and urokinase-type plasminogen activator and its receptor), and adhesion molecules (L-selectin). This effect is strictly dependent on the presence of the RET/PTC1 Tyr-451 (corresponding to RET Tyr-1062 multidocking site). Selected relevant genes (CCL20, CCL2, CXCL8, CXCR4, L-selectin, GM-CSF, IL1B, MMP9, UPA, and SPP1/OPN) were found up-regulated also in clinical samples of PTC, particularly those characterized by RET/PTC activation, local extrathyroid spread, and lymph node metastases, when compared with normal thyroid tissue or follicular thyroid carcinoma. These results, demonstrating that the RET/PTC1 oncogene activates a proinflammatory program, provide a direct link between a transforming human oncogene, inflammation, and malignant behavior.  相似文献   
19.
The aim of this study was to compare the results obtained with an indium-111 scan with those obtained with less expensive and harmless ultrasonography to evaluate the location and inflammatory activity of Crohn's disease. Thirty-one patients previously studied with x-ray underwent abdominal111In scans and ultrasonography (US). Sensitivity and specificity of US in detecting lesions seen with111In scan were 77% and 92.8%, respectively. Sensitivity and specificity of111In scan in detecting x-ray-defined lesions were 69.2% and 92.7%; the figures for US were 73% and 93.3%, respectively. Considering the evaluation of disease activity, ultrasonographic bowel wall thickness was significantly related to scintigraphic intensity of emission (r=0.75 P<0.01). Our experience suggests that US provided information about the location and inflammatory activity of lesions similar to that obtained from111In scan.  相似文献   
20.
Thermoresponsive poly(N-isopropylacrylamide)-grafted silica nanoparticles (SiNPs) have been synthesized and fully characterized by ATR-FTIR, TGA, HRTEM, BET and DLS analysis. Hybrid solid phase extraction (SPE) beds with tuneable pore size and switchable surface chemistry were prepared by packing the polymer-grafted nanoparticles inside SPE cartridges. The cartridges were tested by checking the thermo-regulated elution of model compounds, namely methylene blue, caffeine and amoxicillin. Extraction of the analytes and regeneration of the interaction sites on the sorbent surface was carried out entirely in water solution by changing the external temperature below and above the lower critical solution temperature (LCST) of the polymer. The results demonstrate that the elution of model compounds depends on the temperature-regulated size of the inter-particle voids and on the change of surface properties of the PNIPAM-grafted nanoparticles from hydrophilic to hydrophobic.

Thermoresponsive poly(N-isopropylacrylamide)-grafted silica nanoparticles were synthesized and used to prepare solid phase extraction sorbents with switchable pore size and surface chemistry for temperature-regulated extraction of water pollutants.  相似文献   
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