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101.
Neoplasms of the ovary present an increasing challenge to the physician. Neoplastic ovarian cysts can resemble endometriomas in ultrasound imaging and need to be carefully considered in the differential diagnosis. We report the case of a woman with a strong family history of hereditary breast and ovarian cancer, who presented with a pelvic mass. The young girl refused oncogenetic counseling and genetic testing, even though she had a 50% a priori probability of being a BRCA1 mutation carrier. Pelvic magnetic resonance imaging (MRI) and a comparative analysis of the serum concentration of HE-4 and CA125 biomarkers provided accuracy and sensitivity in the diagnosis of a benign ovarian pathology. Based on this experience, we propose that the sensitivity of a screening program based on a HE4 and CA125 assay and MRI in high risk patients with mutations in the BRCA1 and BRCA2 genes may be considered a useful pre-operative tool for the differential diagnosis of pelvic masses.  相似文献   
102.
Carbon fibers reinforced epoxy resins are used in a wide range of applications, such as automotive and aerospace industry. Because of their thermosetting nature, recycling at the end of the life cycle is a difficult issue. However, lack of recyclability poses environmental concerns to the use of these composite materials. In this article, a sustainable, cost‐effective technological approach aiming at recycling postconsumer carbon fibers reinforced thermosets (CFRT) is proposed. Composites containing 50 and 70 wt% of CFRT particles were prepared by incorporating the filler fraction into a fluidified postconsumer expanded polystyrene matrix. A cold mixing approach consisting in the use of a low boiling solvent as a binder to guarantee the dispersion homogeneity on micro‐ and macroscopic level was set up. For comparison, analog composites were also prepared through melt mixing process. Morphological, mechanical, and thermal analyses allowed to prove the effectiveness of the cold mixing approach and to evaluate the influence of particle size on the performance of new recycled composites. Thermogravimetric analysis and thermal conductivity tests of samples highlighted further peculiarities of the cold mixing process. The approach proposed is an effective recycling technology for CFRT and could be extended to other postconsumer materials. POLYM. COMPOS., 35:1621–1628, 2014. © 2013 Society of Plastics Engineers  相似文献   
103.
Hybrid organic-inorganic sol–gel derived coatings have been prepared by dip coating on glass substrates from alcoholic solutions of tetraethoxysilane (TEOS), methyltriethoxysilane (MTES), 3-aminopropyltriethoxysilane (APTES), 3-glycidoxypropyltrimethoxysilane (GPTMS) and phenyltriethoxysilane (PhTES). The hybrid materials have been fully characterized by means of solid state NMR spectroscopy and X-ray diffraction. The degree of cross-linking and the extent of interaction between silica and silsesquioxane phases appear dependent on the ratio between TEOS and organotrialkoxysilane and on the chemical features of the organic function linked to silicon, and influence the sorption ability towards aromatic compounds of hybrid films. The hybrid coatings have been put into an optical-grade quartz chamber placed into a UV–VIS–NIR spectrophotometer and the organic compounds have been allowed flowing through the chamber recording of molecule absorption spectra vs. time. Absorbance curves vs. time have also been collected at a fixed wavelength for different molecule-coating couples and simple kinetic models have been used for comparing the adsorption capability of the different films, which has been related to the chemical interactions between molecules and coatings.  相似文献   
104.
Natural killer (NK) cells play a role in defence against viral infections by killing infected cells or by producing cytokines and interacting with adaptive immune cells. Killer immunoglobulin-like receptors (KIRs) regulate the activation of NK cells through their interaction with human leucocyte antigens (HLA). Ninety-six Sicilian patients positive to Human Immunodeficiency Virus-1 (HIV) and ninety-two Sicilian patients positive to SARS-CoV-2 were genotyped for KIRs and their HLA ligands. We also included fifty-six Sicilian patients with chronic hepatitis B (CHB) already recruited in our previous study. The aim of this study was to compare the distribution of KIR–HLA genes/groups of these three different infected populations with healthy Sicilian donors from the literature. We showed that the inhibitory KIR3DL1 gene and the KIR3DL1/HLA-B Bw4 pairing were more prevalent in individual CHB. At the same time, the frequency of HLA-C2 was increased in CHB compared to other groups. In contrast, the HLA-C1 ligand seems to have no contribution to CHB progression whereas it was significantly higher in COVID-19 and HIV-positive than healthy controls. These results suggest that specific KIR–HLA combinations can predict the outcome/susceptibility of these viral infections and allows to plan successful customized therapeutic strategies.  相似文献   
105.
106.
Brugada Syndrome (BrS) is an inherited arrhythmogenic disorder with an increased risk of sudden cardiac death. Recent evidence suggests that BrS should be considered as an oligogenic or polygenic condition. Mutations in genes associated with BrS are found in about one-third of patients and they mainly disrupt the cardiac sodium channel NaV1.5, which is considered the main cause of the disease. However, voltage-gated channel’s activity could be impacted by post-translational modifications such as sialylation, but their role in BrS remains unknown. Thus, we analyzed high risk BrS patients (n = 42) and healthy controls (n = 42) to assess an involvement of sialylation in BrS. Significant alterations in gene expression and protein sialylation were detected in Peripheral Blood Mononuclear Cells (PBMCs) from BrS patients. These changes were significantly associated with the phenotypic expression of the disease, as the size of the arrhythmogenic substrate and the duration of epicardial electrical abnormalities. Moreover, protein desialylation caused a reduction in the sodium current in an in vitro NaV1.5-overexpressing model. Dysregulation of the sialylation machinery provides definitive evidence that BrS affects extracardiac tissues, suggesting an underlying cause of the disease. Moreover, detection of these changes at the systemic level and their correlation with the clinical phenotype hint at the existence of a biomarker signature for BrS.  相似文献   
107.
Powdery mildew (PM) is an economically important foliar disease of cultivated cereals worldwide. The cultivation of disease-resistant varieties is considered the most efficient, sustainable and economical strategy for disease management. The objectives of the current study were to fine map the chromosomal region harboring the wild emmer PM resistance locus Pm36 and to identify candidate genes by exploiting the improved tetraploid wheat genomic resources. A set of backcross inbred lines (BILs) of durum wheat were genotyped with the SNP 25K chip array and comparison of the PM-resistant and susceptible lines defined a 1.5 cM region (physical interval of 1.08 Mb) harboring Pm36. The genetic map constructed with F2:3 progenies derived by crossing the PM resistant line 5BIL-42 and the durum parent Latino, restricted to 0.3 cM the genetic distance between Pm36 and the SNP marker IWB22904 (physical distance 0.515 Mb). The distribution of the marker interval including Pm36 in a tetraploid wheat collection indicated that the positive allele was largely present in the domesticated and wild emmer Triticum turgidum spp. dicoccum and ssp. dicoccoides. Ten high-confidence protein coding genes were identified in the Pm36 region of the emmer, durum and bread wheat reference genomes, while three added genes showed no homologous in the emmer genome. The tightly linked markers can be used for marker-assisted selection in wheat breeding programs, and as starting point for the Pm36 map-based cloning.  相似文献   
108.
In this paper we develop new rolling-horizon and fix-and-relax heuristics for the identical parallel machine lot-sizing and scheduling problem with sequence-dependent set-up costs. Unlike previous papers, our procedures are based on a compact formulation relying on the hypotheses of identical machines. This feature makes our approach suitable for large-scale applications (with hundreds of machines) arising in the textile and fiberglass industries. Moreover, our procedures are shown to provide a feasible solution for any feasible instance. Comparisons with lower bounds provided by a truncated branch-and-bound show that the gap between the best heuristic solution and the lower bound never exceeds 3%.  相似文献   
109.
The antibiotic and nematocidal activities of extracts from two coastal lichen species collected on Lampedusa Island (Sicily), Ramalina implexa Nyl. and Roccella phycopsis Ach., were tested. Methyl orsellinate, orcinol, (+)-montagnetol, and for the first time 4-chlororcinol were isolated from Roccella phycopsis. (+)-Usnic acid was obtained from Ramalina implexa. The crude organic extract of both lichen species showed strong antibiotic activity against some bacterial species and nematocidal activity. Among all the pure metabolites tested against the infective juveniles (J2) of the root-knot nematode (RKN) Meloydogine incognita, (+)-usnic acid, orcinol, and (+)-montagnetol had significant nematocidal activity, comparable with that of the commercial nematocide Velum® Prime, and thus they showed potential application in agriculture as a biopesticide. On the contrary, methyl orsellinate and 4-chlororcinol had no nematocidal effect. These results suggest that the substituent pattern at ortho-para-position in respect to both hydroxyl groups of resorcine moiety, which is present in all metabolites, seems very important for nematocidal activity. The organic extracts of both lichens were also tested against some Gram-positive and Gram-negative bacteria. Both extracts were active against Gram-positive species. The extract of Ramalina implexa showed, among Gram-negative species, activity against Escherichia coli and Acinetobacter baumannii, while that from Roccella phycopsis was effective towards all test strains, with the exception of Pseudomonas aeruginosa. The antimicrobial activity of (+)-usnic acid, methyl orsellinate, and (+)-montagnetol is already known, so tests were focused on orcinol and 4-chlororcinol. The former showed antibacterial activity against all Gram positive and Gram-negative test strains, with the exception of A. baumannii and K. pneumoniae, while the latter exhibited a potent antibacterial activity against Gram-positive test strains and among Gram-negative strains, was effective against A. baumannii and K. pneumonia. These results suggest, for orcinol and 4-chlororcinol, an interesting antibiotic potential against both Gram-positive and Gram-negative bacterial strains.  相似文献   
110.
A breached nasal epithelial barrier plays an important role in driving allergic rhinitis (AR). Corticosteroids remain the standard of care (SoC) but come with side effects, thus alternative safe and effective treatments able to avoid inflammation and restore barrier integrity are needed. The aim of the present study is to evaluate the barrier-forming capacity of a xyloglucan-based nasal spray (XG) and compare its efficacy to several SoC treatments (corticosteroid spray, oral mast-cell stabilizer and oral antihistamine) in reducing allergic responses in addition to its effect when concomitantly administered with an antihistamine. An ovalbumin (OVA)-induced mouse AR model was used. XG shows a significant efficacy in reducing histological damage in AR mice; improves nasal rubbing and histamine-induced hyper-responsiveness. Total and OVA-specific IgE as well as pro-inflammatory cytokines are significantly reduced compared to OVA challenged-mice, with im-proved efficacy when used as an add-on treatment. However, XG reduces mucous secreting cells (PAS-positive) and mucin mRNA expression similar to the corticosteroid-treated mice. XG-spray maintains tight junction protein expression (ZO-1) and conversely decreases HDAC1 significantly; the latter being highly expressed in AR patients. Moreover, the concomitant treatment showed in all of the endpoints a similar efficacy to the corticosteroids. This innovative approach may represent a novel therapeutic strategy for nasal respiratory diseases like AR, reducing undesirable side effects and improving the quality of life in patients.  相似文献   
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