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41.
With the progress of sequencing technologies, an ever-increasing number of variants of unknown functional and clinical significance (VUS) have been identified in both coding and non-coding regions of the main Breast Cancer (BC) predisposition genes. The aim of this study is to identify a mutational profile of coding and intron-exon junction regions of 12 moderate penetrance genes (ATM, BRIP1, CDH1, CHEK2, NBN, PALB2, PTEN, RAD50, RAD51C, RAD51D, STK11, TP53) in a cohort of 450 Italian patients with Hereditary Breast/Ovarian Cancer Syndrome, wild type for germline mutation in BRCA1/2 genes. The analysis was extended to 5′UTR and 3′UTR of all the genes listed above and to the BRCA1 and BRCA2 known regulatory regions in a subset of 120 patients. The screening was performed through NGS target resequencing on the Illumina platform MiSeq. 8.7% of the patients analyzed is carriers of class 5/4 coding variants in the ATM (3.6%), BRIP1 (1.6%), CHEK2 (1.8%), PALB2 (0.7%), RAD51C (0.4%), RAD51D (0.4%), and TP53 (0.2%) genes, while variants of uncertain pathological significance (VUSs)/class 3 were identified in 9.1% of the samples. In intron-exon junctions and in regulatory regions, variants were detected respectively in 5.1% and in 32.5% of the cases analyzed. The average age of disease onset of 44.4 in non-coding variant carriers is absolutely similar to the average age of disease onset in coding variant carriers for each proband’s group with the same cancer type. Furthermore, there is not a statistically significant difference in the proportion of cases with a tumor onset under age of 40 between the two groups, but the presence of multiple non-coding variants in the same patient may affect the aggressiveness of the tumor and it is worth underlining that 25% of patients with an aggressive tumor are carriers of a PTEN 3′UTR-variant. This data provides initial information on how important it might be to extend mutational screening to the regulatory regions in clinical practice.  相似文献   
42.
Titanium surface is an important factor in achieving osseointegration during the early wound healing of dental implants in alveolar bone. The purpose of this study was to evaluate sandblasted-etched surface implants to investigate the osseointegration. In the present study, we used two different types of sandblasted-etched surface implants, an SLA™ surface and a Nanoblast Plus™ surface. Roughness and chemical composition were evaluated by a white light interferometer microscope and X-ray photoelectron spectroscopy, respectively. The SLA™ surface exhibited the higher values (Ra 3.05 μm) of rugosity compared to the Nanoblast Plus™ surface (Ra 1.78 μm). Both types of implants were inserted in the femoral condyles of ten New Zealand white rabbits. After 12 weeks, histological and histomorphometric analysis was performed. All the implants were osseointegrated and no signs of infection were observed. Histomorphometric analysis revealed that the bone–implant contact % (BIC) ratio was similar around the SLA™ implants (63.74 ± 13.61) than around the Nanoblast Plus™ implants (62.83 ± 9.91). Both implant surfaces demonstrated a favorable bone response, confirming the relevance of the sandblasted-etched surface on implant osseointegration.  相似文献   
43.
Approximately 25% of colorectal cancer (CRC) patients develop peritoneal metastasis, a condition associated with a bleak prognosis. The CRC peritoneal dissemination cascade involves the shedding of cancer cells from the primary tumor, their transport through the peritoneal cavity, their adhesion to the peritoneal mesothelial cells (PMCs) that line all peritoneal organs, and invasion of cancer cells through this mesothelial cell barrier and underlying stroma to establish new metastatic foci. Exosomes produced by cancer cells have been shown to influence many processes related to cancer progression and metastasis. In epithelial ovarian cancer these extracellular vesicles (EVs) have been shown to favor different steps of the peritoneal dissemination cascade by changing the functional phenotype of cancer cells and PMCs. Little is currently known, however, about the roles played by exosomes in the pathogenesis and peritoneal metastasis cascade of CRC and especially about the molecules that mediate their interaction and uptake by target PMCs and tumor cells. We isolated exosomes by size−exclusion chromatography from CRC cells and performed cell-adhesion assays to immobilized exosomes in the presence of blocking antibodies against surface proteins and measured the uptake of fluorescently-labelled exosomes. We report here that the interaction between integrin α5β1 on CRC cells (and PMCs) and its ligand ADAM17 on exosomes mediated the binding and uptake of CRC-derived exosomes. Furthermore, this process was negatively regulated by the expression of tetraspanin CD9 on exosomes.  相似文献   
44.
This paper presents a study of the relationship between the magnetic properties and microstructure of nanocomposite Ni/MnO, Ni/CoO, Co/MnO, Co/CoO. The objective is to understand how the coupling interface FM/AFM (ferromagnetic/anti-ferromagnetic) manifests itself in magnetic response of these materials to an applied field. Sample preparation was performed using mechanochemical synthesis by means of a ball mill planetary type high power at normal atmosphere. The characterization was done by XRD (X-ray diffraction), SEM (scanning electron microscopy) and VSM (vibrating sample magnetometry). Analyzing the XRD peaks of the samples studied, there was a decrease in the average particle diameter with increasing milling time, which is important in the magnetic interactions of the atoms of the surface. In addition, the diffraction pattern showed formation of new phases by oxidation interfering with the magnetic measurements. Analyses by SEM show chipboard multiform nano- and micrometer-sized grains on the surface of the clusters being responsible for the interaction. The magnetic measurements show a strong coupling between the phases present in nanocomposites showing once again that the MS (mechanosynthesis) is a powerful technique for this kind of purpose. The effect of the decrease in crystallite size leads to large variations of magnetic properties of the material which have been specifically observed changes in HC (coercive field) in the RM (remanent magnetization) and SM (saturation magnetization). The decrease in crystallite size in the course of grinding intensifies the effects that depend on the surface-to-volume ratio of the material. M vs. T measures were taken for different values of applied field and found a jump in the moment of the sample near the N6el temperature of the antiferromagnetic.  相似文献   
45.
In this paper we propose an efficient and novel technique that handles production discontinuities through a resampling of the production data, eliminating high frequency production details in a transformed domain. The technique also reduces non-monotonic behavior and results in a response more suitable for the GTTI based misfit calculations. Our proposed approach has been applied to an offshore turbidite reservoir with extensive well intervention resulting in highly detailed production responses. The static model contains more than three-hundred-thousand cells, complex sand depositional distribution combined with fault structures, four pairs of injector-producers, deviated producing wells and more than 8 years of production history. Previous history matching attempts using traditional approaches had difficulties matching production response at the individual well level. With our proposed modifications to the GTTI approach, a significant improvement was obtained on the well level match quality. Most importantly, by visualizing the streamlines and the dynamic adjustment of flow paths during history matching, we could easily identify the areas of inconsistency between the geologic model and the production data. The calibrated geologic model and streamline trajectories provided important insight about communication within sand channels, differences in flow paths and barriers that have not been included in the previous geologic and seismic interpretation.  相似文献   
46.
The effect of heat‐moisture treatment (HMT) on the properties of pinhão starches under different moisture and heat conditions was investigated. The starches were adjusted to 15, 20 and 25% moisture levels and heated to 100, 110 and 120°C for 1 h. The X‐ray diffractograms, swelling power, solubility, gel hardness, pasting properties and thermal properties of the native and HMT pinhão starches were evaluated. Compared to native starch, there was an increase in the X‐ray intensity and gel hardness of HMT starches, with the exception of the 25% moisture‐treated and 120°C heat‐treated starch. HMT reduced the swelling power and solubility of the pinhão starches when compared to native starch. There was an increase in the pasting temperature, final viscosity and setback and a decrease in the peak viscosity and breakdown of HMT pinhão starches compared to native starch. HMT increases the gelatinisation temperature of native pinhão starch and reduces gelatinisation enthalpy.  相似文献   
47.
We validate the chlortetracycline (CTC) technique for the evaluation of capacitation and acrosome reaction-like changes in ram sperm, carrying out a double estimation of the acrosome status after treatment with lysophosphatidylcholine, using fluorescein isocyanate (FITC)-RCA/ethidium homodimer 1 (EthD-1) and CTC/EthD-1. Highly consistent results and a positive correlation between the results of acrosome-reacted sperm evaluated with both techniques were obtained. In this study, we evaluate the effects of ram sperm capacitation of BSA, Ca(2+), NaHCO(3) and cAMP agonists and their influence on the associated protein tyrosine phosphorylation. We found a time-dependent increase in capacitation related to protein tyrosine phosphorylation, either in the absence or the presence of BSA. The addition of an increasing concentration of cholesterol to samples containing BSA did not influence results. The effect of bicarbonate was concentration-dependent, with a significantly lowered value of non-capacitated sperm in the presence 18 and 25 mM. The addition of extracellular calcium did not significantly increase either the proportion of capacitated sperm or the protein tyrosine phosphorylation signalling, although a significantly higher value of acrosome-reacted sperm was found in samples containing 4 mM Ca(2+). cAMP agonists increased capacitated sperm and protein tyrosine phosphorylation signalling. The inhibition of protein kinase A by H-89 caused a decrease in sperm capacitation. Addition of a calcium-entry blocker (Verapamil; Sigma) did not influence results, which suggests that the calcium entry blocker was unable to inhibit the calcium influx associated with capacitation in ram sperm. Our findings might benefit our understanding of the biochemical mechanisms involved in mammalian sperm capacitation and ultimately, fertility.  相似文献   
48.
MgO is one of the sintering aids most commonly used in the processing of mullite bodies. However, few studies have investigated the influence of MgO on the densification and microstructural development of mullite bodies, and the amount of MgO to be used as dopant is still a matter of controversy. Thus, this work investigated the efficiency of small amounts of MgO in the sintering of industrial mullite. MgO was added to obtain dopant concentrations of 0.1 and 0.5 wt.% in the mullite samples. Doped and nondoped samples were produced by cold isostatic pressing (CIP) at 200 MPa and pressureless sintering at 1500, 1550, 1600 and 1650 °C for 2 h. The use of 0.1 and 0.5 wt.% of MgO increased the final density of the sintered samples, with the doped samples reaching densities of 99% and the nondoped samples reaching densities of 95%. Elongated mullite grains were observed in the nondoped samples when their density fell below 95%, while the microstructures of bodies containing 0.1 wt.% of MgO were controlled up to densities of 98%. The 0.5% doped samples required lower sintering temperatures, however elongated mullite grains were observed when densities of 99% were reached.  相似文献   
49.
Nanoparticles tend to form large clusters (aggregates and agglomerates) which need to be broken up when dispersing in a liquid. The dispersion of nanoparticle clusters has been studied to investigate the kinetics and mechanisms of break up with two types of particles: fumed silica and aluminium oxide. Results obtained under different processing conditions using an in-line rotor-stator are reported. It could be concluded that break up occurs predominantly through erosion in the case of silica and shattering with aluminium oxide.  相似文献   
50.
Using non-conventional starch can benefit the industry since it can present different properties. It also can lead to new properties upon physical modification, which improves its derivate film properties. Therefore, the aim of this work is to evaluate the heat–moisture treatment (HMT) on pinhão starch and its effectiveness in film properties. After isolation using water as a solvent, the pinhão starch is treated by HMT for 16 h at 110 °C. Native and HMTed starches are used to produce biodegradable films. Pinhão starch and starch films chemical and physical properties are properly characterized. The HMT causes some changes in short-range ordered structures, reduces the relative crystallinity, and shifts the pinhão starch from C-type to A-type. Also, HMT decreases the peak viscosity and the breakdown, and improves thermal stability. These starch changes upon HMT reduces water vapor permeability, increases tensile strength, and elongation at the break of pinhão starch films. Desirable changes in starch and film properties are achieved by physically modifying pinhão starch using HMT, which is a promising alternative to chemical modifications.  相似文献   
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