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91.
Primary graft dysfunction (PGD) after lung transplantation (LT) is a heterogeneous syndrome that comprises clinical presentations with diverse grades of severity. Proadrenomedullin (proADM) levels may be associated with PGD and may enhance its relationship with outcomes. We prospectively included 100 LT recipients. Plasma levels of proADM were measured at 24, 48 and 72 h after admission to the intensive care unit (ICU). We assessed their relationship with PGD grade and ICU mortality. Fifty patients (50%) presented grade 3 PGD at ICU admission. Twenty‐two patients (22%) developed grade 3 PGD at 72 h, the only grade associated with higher mortality (odds ratio 6.84, 95% confidence interval [CI] 1.47–38.44). ProADM levels measured at 24 h (3.25 vs. 1.61 nmol/L; p = 0.016) and 72 h (2.17 vs. 1.35 nmol/L; p = 0.011) were higher in these patients than the rest of the population. When we added the individual predictive utility of grade 3 PGD at 72 h for ICU mortality (area under the curve [AUC] 0.72, 95% CI 0.53–0.90) to that of ProADM at 72 h, the predictive value of the model improved (AUC 0.81, 95% CI 0.65–0.97). Higher levels of proADM measured following LT are associated with grade 3 PGD at 72 h. ProADM enhances the association of this entity with mortality.  相似文献   
92.
Endogenous levels of glucocorticoids rise during pregnancy to warrant development and maturation of the fetal organs close to birth. However, during most of the gestation, the fetus is protected from excessive biologically active endogenous glucocorticoids by placental and fetal expression of 11β-hydroxysteroid dehydrogenase 2 (11β-HSD2). Maternal stress, which may overwhelm placental 11β-HSD2 activity with high glucocorticoid levels, or administration of synthetic glucocorticoids to improve the survival chances of the premature newborn, are associated to postnatal increased risk for immune diseases. Fetal exposure to excessive glucocorticoids may underlie this altered postnatal immunity. Here, we revise the role that placental and fetal 11β-HSD2, fetal glucocorticoid exposure, and programming of the offspring’s the hypothalamic-pituitary-adrenal (HPA) axis play on concerted steps in immune fetal development. We could identify gaps in knowledge about glucocorticoid-induced programming of immune diseases. Finally, based on current evidence about glucocorticoid and HPA axis-mediated immune regulation, we hypothesize on mechanisms that could drive the enhanced risk for atopies, infections, and type I diabetes in offspring that were prenatally exposed to glucocorticoids.  相似文献   
93.
BACKGROUND: Insulin receptor substrate 1 (IRS-1), a cytoplasmic protein transmitting signals from the insulin and insulin-like growth factor 1 receptors, has been implicated in breast cancer. Previously, it was reported that IRS-1 can be translocated to the nucleus and modulate oestrogen receptor alpha (ERalpha) activity in vitro. However, the expression of nuclear IRS-1 in breast cancer biopsy specimens has never been examined. AIMS: To assess whether nuclear IRS-1 is present in breast cancer and non-cancer mammary epithelium, and whether it correlates with other markers, especially ERalpha. Parallel studies were carried out for the expression of cytoplasmatic IRS-1. METHODS: IRS-1 and ERalpha expression was assessed by immunohistochemical analysis. Data were evaluated using Pearson's correlation, linear regression and receiver operating characteristic analysis. RESULTS: Median nuclear IRS-1 expression was found to be low in normal mammary epithelial cells (1.6%) and high in benign tumours (20.5%), ductal grade 2 carcinoma (11.0%) and lobular carcinoma (approximately 30%). Median ERalpha expression in normal epithelium, benign tumours, ductal cancer grade 2 and 3, and lobular cancer grade 2 and 3 were 10.5, 20.5, 65.0, 0.0, 80 and 15%, respectively. Nuclear IRS-1 and ERalpha positively correlated in ductal cancer (p<0.001) and benign tumours (p<0.01), but were not associated in lobular cancer and normal mammary epithelium. In ductal carcinoma, both nuclear IRS-1 and ERalpha negatively correlated with tumour grade, size, mitotic index and lymph node involvement. Cytoplasmic IRS-1 was expressed in all specimens and positively correlated with ERalpha in ductal cancer. CONCLUSIONS: A positive association between nuclear IRS-1 and ERalpha is a characteristic for ductal breast cancer and marks a more differentiated, non-metastatic phenotype.  相似文献   
94.
BACKGROUND: Results from mice lacking the androgen receptor (AR) showed that it is critical for the proper development and function of the testes. The aim of this study was to investigate whether a functional AR is present in human sperm. METHODS: The expression of AR and its effects on sperm were evaluated by RT-PCR, Western Blot, Immunocytochemistry, PI3Kinase and DNA laddering assays. RESULTS: We showed in human sperm that AR is located at the head region. Dihydrotestosterone (DHT), in a dose-dependent manner, leads to the rapid phosphorylation of the AR on tyrosine, serine and threonine residues and this effect was reduced by the AR antagonist hydroxyflutamide (OH-Flut). The effects of AR were evaluated on the phosphoinositide-3 kinase/protein kinase B (PI3K/AKT) pathway. Specifically, 0.1 and 1 nM DHT stimulated PI3K activity, whereas 10 nM DHT decreased PI3K activity and levels of p-AKT S473 and p-AKT T308, p-BCL2, and enhanced phosphatase and tensin homologue (PTEN) phosphorylation. In addition, 10 nM DHT was able to induce the cleavage of caspases 8, 9 and 3 and cause DNA laddering, and these effects were reversed either by casodex or OHFlut. By using wortmannin, a specific PI3K inhibitor, the cleavage of caspase 3 was reproduced, confirming that in sperm the PI3K/AKT pathway is involved in caspase activation. CONCLUSIONS: Human sperm express a functional AR that have the ability to modulate the PI3K/AKT pathway, on the basis of androgen concentration.  相似文献   
95.
Multiple myelomas (MM) recently have been stratified into five groups (TC1-TC5) on the basis of the presence of the recurrent IgH chromosomal translocation and cyclin D expression. Cyclin D1 is detectable in up to one third of MM patients and plays crucial role in the regulation of G1-S transition in cell cycle. To evaluate the mechanisms of cyclin D1 overexpression, fluorescence in situ hybridization analysis with specific probes for the CCND1 gene and t(11;14)(q13;q32) were performed on highly purified plasma cells from bone marrow samples of 30 MM patients at diagnosis. CCND1 gene overexpression was detected in 14/30 cases (46.6%). Patients with evidence of the t(11;14) showed strong nuclear staining for cyclin D1 (TC1 group) and 7/8 demonstrated CCND1 overexpression. The remaining 7/15 cases with increased CCND1 gene copy numbers lacked the t(11;14) and showed low to negative levels of cyclin D1 protein (TC2 group). Trisomy 11 was demonstrated in 2/8 cases carrying the t(11;14) (TC1), 6/7 overexpressing cyclin D1 without the translocation (TC2), and 4/15 negative for both alterations (TC3-TC5). According to our data, trisomy 11 does not appear to directly cause CCND1 gene overexpression because it was present in 4/15 patients without the overexpression of the CCND1 gene and in 2/8 patients carrying the t(11;14). One patient belonging to the TC2 group overexpressed cyclin D1 and lacked both trisomy and translocation, suggesting that cyclin D1 can be dysregulated by additional mechanisms. In the TC2 group, trisomy 11 may probably be considered as a recurrent polisomy of the hyperdiploid status.  相似文献   
96.
Optical mapping of excitation dynamically tracks electrical waves travelling through cardiac or brain tissue by the use of fluorescent dyes. There are several characteristics that set optical mapping apart from other imaging modalities: dynamically changing signals requiring short exposure times, dim fluorescence demanding sensitive sensors and wide fields of view (low magnification) resulting in poor optical performance. These conditions necessitate the use of optics with good light gathering ability, i.e. lenses having high numerical aperture. Previous optical mapping studies often used sensor resolution to estimate the minimum spatial feature resolvable, assuming perfect optics and infinite contrast. We examine here the influence of finite contrast and real optics on the effective spatial resolution in optical mapping under broad-field illumination for both lateral (in-plane) resolution and axial (depth) resolution of collected fluorescence signals.  相似文献   
97.
The study investigated the effect of chamomile extract obtained in supercritical carbon dioxide conditions on the basic properties of pharmaceutical ointments. A total of five formulations were designed and prepared, differing in the weight ratio of sunflower oil to chamomile extract (5:0, 3.5:1.5, 2.5:2.5, 1.5:3.5 and 0:5). An increase in the concentration of chamomile extract was found to be accompanied by a decrease in hardness, adhesive power and flow limit. Based on viscosity measurements it was shown that ointments containing the hydrophobic plant extract under study were prone to larger drops in viscosity under the effect of the set shear rate. It was determined that from the viewpoint of ointment spreadability and application to the skin, the optimum concentration of chamomile extract for the studied formulations should be within the range of 1.5–2.5%. Furthermore, the addition of chamomile extract to ointments was found to give samples a yellow-green color. Green was observed to be the dominant color, and its saturation and shade varied for different formulations.  相似文献   
98.
The sequence polymorphisms of intergenic transcribed spacer and the antifungal susceptibility profile of 18 Trichosporon asahii isolates from Spain, Argentina, and Brazil together with 43 intergenic transcribed spacer 1 sequences deposited in the GenBank were analyzed. Six genotypes were detected instead of 5 genotypes described previously. Genotype 1 was the most common found comprising 57.3% of all strains, followed by genotype 3 (14.7%) and genotype 5 (13.1%). Spanish strains had members in all genotypes except 2, whereas South American isolates were grouped with genotypes 1, 3, and 6. Our results indicate that all genotypes are present in at least 2 countries suggesting a worldwide distribution. On the other hand, genotype 6 was not previously described but was only composed of 2 South American strains isolated from a subcutaneous abscess and skin. All isolates showed amphotericin B MICs>or=2 mg/L supporting the in vitro resistance of this species to this antifungal. Three isolates from South America showed high MICs to all antifungals analyzed. The true epidemiologic usefulness of classifying T. asahii in genotypes should be ascertaining analyzing a high number of isolates from many countries.  相似文献   
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