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11.
Combined AntiRetroviral Treatments (cARTs) used for HIV infection may result in varied metabolic complications, which in some cases, may be related to patient genetic factors, particularly microRNAs. The use of monozygotic twins, differing only for HIV infection, presents a unique and powerful model for the controlled analysis of potential alterations of miRNAs regulation consequent to cART treatment. Profiling of 2578 mature miRNA in the subcutaneous (SC) adipose tissue and plasma of monozygotic twins was investigated by the GeneChip® miRNA 4.1 array. Real-time PCR and ddPCR experiments were performed in order to validate differentially expressed miRNAs. Target genes of deregulated miRNAs were predicted by the miRDB database (prediction score > 70) and enrichment analysis was carried out with g:Profiler. Processes in SC adipose tissue most greatly affected by miRNA up-regulation included (i) macromolecular metabolic processes, (ii) regulation of neurogenesis, and (iii) protein phosphorylation. Furthermore, KEGG analysis revealed miRNA up-regulation involvement in (i) insulin signaling pathways, (ii) neurotrophin signaling pathways, and (iii) pancreatic cancer. By contrast, miRNA up-regulation in plasma was involved in (i) melanoma, (ii) p53 signaling pathways, and (iii) focal adhesion. Our findings suggest a mechanism that may increase the predisposition of HIV+ patients to insulin resistance and cancer.  相似文献   
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Oral cancer often presents with aggressive behavior and a high risk of recurrence and metastasis. For oral squamous cell carcinoma (OSCC), which is the most frequent histological subtype, therapy strategies include surgery, radiation therapy, chemotherapy, immune checkpoint inhibitors, and EGFR inhibitors. Recently, a Trop-2 antibody-drug conjugate (ADC) has been approved in the United States of America for the treatment of advanced triple-negative breast cancer. However, this ADC has also been tested in other solid tumors including head & neck squamous cell carcinoma. The prognostic impact of Trop-2 has already been reported for several cancers. We studied the prognostic influence of Trop-2 protein expression on OSCC patients’ survival. The cohort comprised n = 229 OSCC patients with available archived tumor tissue and corresponding non-neoplastic oral mucosa tissue. Using immunohistochemistry, we investigated Trop-2 expression in both the central and peripheral regions of each tumor and in corresponding non-neoplastic oral mucosa. In patients suffering from OSCC with combined high central and low peripheral Trop-2 expression, five-year overall survival (OS) was 41.2%, whereas 55.6% of OSCC patients who presented lower central and/or higher peripheral tumoral Trop-2 expression were alive after five years (p = 0.075). In multivariate Cox regression, the expression pattern of high central tumoral and lower peripheral Trop-2 expression was significantly correlated with impaired OS (HR = 1.802, 95%-CI: 1.134–2.864; p = 0.013) and recurrence-free survival (RFS) (HR = 1.633, 95%-CI: 1.042–2.560; p = 0.033), respectively, when adjusting for co-variables. Hence, Trop-2 may serve as an independent prognostic biomarker in OSCC. In subsequent studies, the pathophysiological meaning of downregulated Trop-2 expression in the OSCC periphery has to be analyzed.  相似文献   
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The reuse of plastic components of waste electrical and electronic equipment (WEEE) is an important concern both for environmental issues and to preserve the material resources, with minimum energy consumption. Considering that polystyrene fraction was reported as approximate 80% of the total amount of WEEE plastic, this article aims to evaluate the recycling of this fraction, without separation by components, by melt compounding with styrene-butadiene block-copolymer (SBS) and hydrogenated and maleinized SBS, the blend of the two elastomers acting both as an impact modifier and compatibilizer. The composites are characterized by mechanical analysis, impact tests, dynamic mechanical analysis, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, energy dispersive X-ray analysis, and X-ray diffraction. The recycling conditions of the polystyrene fraction as composites without eliminating the WEEE additives for improved UV and flame resistance, with physical mechanical properties comparable to those of high-impact polystyrene resulted from the study. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48329.  相似文献   
14.
The distribution of mixing in a split-cylinder gas-lift bioreactor has been investigated for suspensions of immobilized Yarrowia lipolytica cells with particles diameter varying between 3 and 4.2 mm. The results indicated important variation of mixing time on the height of riser or downcomer, as well as different behavior of suspensions flows in these two regions. Therefore, for the riser, the mixing efficiency increases from its bottom to the top, allowing the biocatalyst particles with intermediate size (3.6-mm diameter) reaching the most intense circulation of suspension. The analysis of the suspension flow in the downcomer region revealed that the intermediate positions are associated with the highest mixing mainly for the largest immobilized yeast particles (4.2-mm diameter). In both cases, the influence of aeration on turbulence extent is positive only for air superficial velocity up to 1.05–1.35 × 10?3 m/s, the magnitude of this effect being correlated with the biocatalyst size and position on the riser or downcomer. By means of the experimental data, mathematical correlations for mixing time have been proposed for each circulation region, taking into consideration both the operational parameters and the distance from the bioreactor bottom. These equations offer a good concordance with the experiment, the average deviation being of 5.82% for the riser and 6.06% for the downcomer zone.  相似文献   
15.
We studied the ability of Lactobacillus pentosus 39, a BLS (Bacteriocin-like substance)-producing strain, to control the growth of Aeromonas hydrophila ATCC 14715 and Listeria monocytogenes ATCC 19117 artificially added to fresh salmon fillets at refrigeration temperatures and under simulated cold-chain break conditions.At refrigeration temperatures, Lb. pentosus 39 protective culture and its putative bacteriocin significantly reduced A. hydrophila counts compared with the control (2.1 and 1.4 log CFU/g reductions, respectively). Similar behaviour was observed for L. monocytogenes (3.6 and 1.3 log CFU/g reductions, respectively).Under simulated cold-chain break conditions, an increase in temperature (30°C for 12h) produced an evident increase in the development of A. hydrophila, L. monocytogenes, but also of Lb. pentosus 39, with a consequent increase in BLS production. This condition resulted in a greater reduction of both pathogens compared with samples stored at 4°C throughout the experiment (2.8 log CFU/g reduction for A. hydrophila, 5.8 log CFU/g reduction for L. monocytogenes). In samples treated with the putative bacteriocin alone, a less marked decrease was observed.Our study demonstrates the capability of Lb. pentosus 39 to control the growth of psychrotrophic bacteria in an experimental seafood model system. A similar biopreservation technology could provide more prolonged shelf-life during storage of ready-to-eat seafood, ensuring safety, even under extreme conditions.  相似文献   
16.
This paper presents the performances of an original longitudinal magnetization system, designed to assure the magnetic flux concentration on the tube wall. This magnetization system is made of several small peripheral solenoids disposed around each tube, parallel to the tube axis, and was used to investigate the interaction between the arc and the magnetic field in case of MIAB (Magnetically Impelled Arc Butt) welding of low carbon steel thin-walled tubes. The main research objective was the development of process parametrical windows for assuring qualitative joint achievement. Macro- and micro-structural analysis accompanies the hardness tests made on corresponding welded samples, demonstrating the operational process maps in producing sound MIAB joints. The paper also discusses the process main stages based on corresponding images resulting from process monitoring, from arc initiation to the emergence of molten metal when upsetting starts and the weld is formed.  相似文献   
17.
In traumatically brain-injured (TBI) patients (n?=?83), memory performance was examined on the Warrington Recognition Memory Test, Rey-Osterrieth Complex Figure, and the Logical Memory and Visual Reproduction subtests of the Wechsler Memory Scale-Revised in relationship to time postinjury and structural changes based on MRI volumetry, including hippocampus volume. Significant trauma-induced changes were observed, including hippocampal atrophy. Structure-function relationships generally became significant only after 90 days postinjury. Memory tended to relate more to the degree of hippocampal atrophy, particularly left hippocampus, than to nonspecific indicators such as the temporal horns or the ventricle-to-brain ratio. A stronger relationship with left versus right hippocampus was evident for measures of verbal and supposedly nonverbal memory. These results are discussed with regard to the role the hippocampus may play in a neural system of memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Almost all tumors are composed of a heterogeneous cell population, making them difficult to treat. A small cancer stem cell population with a low proliferation rate and a high tumorigenic potential is thought to be responsible for cancer development, metastasis and resistance to therapy. Stem cells were reported to be involved in both normal development and carcinogenesis, some molecular mechanisms being common in both processes. No less controversial, stem cells are considered to be important in treatment of malignant diseases both as targets and drug carriers. The efforts to understand the role of different signalling in cancer stem cells requires in depth knowledge about the mechanisms that control their self-renewal, differentiation and malignant potential. The aim of this paper is to discuss insights into cancer stem cells historical background and to provide a brief review of the new therapeutic strategies for targeting cancer stem cells.  相似文献   
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