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1.
Anna Tylutka Barbara Morawin Edyta Wawrzyniak-Gramacka Eryk Wacka Wiktoria Nowicka Jaroslaw Hiczkiewicz Agnieszka Zembron-Lacny 《International journal of molecular sciences》2022,23(21)
The immunosenescence-related disproportion in T lymphocytes may have important consequences for endothelial dysfunction, which is a key event in vascular aging. The study was designed to assess the prognostic values of the inflammatory-immune profile to better predict and prevent vascular diseases associated with old age. Eighty individuals aged 70.9 ± 5.3 years were allocated to a low- (LGI) or high-grade inflammation (HGI) group based on CRP (<3 or ≥3 mg/L) as a conventional risk marker of cardiovascular diseases. Significant changes in inflammatory and endothelium-specific variables IL-1β, IL-6, TNFα, oxLDL, H2O2, NO, 3-nitrotyrosine, and endothelial progenitor cells (OR 7.61, 95% CI 2.56–29.05, p < 0.0001), confirmed their interplay in vascular inflammation. The flow-cytometry analysis demonstrated a high disproportion in T lymphocytes CD4+ and CD8+ between LGI and HGI groups. CRP was <3 mg/mL for the CD4/CD8 ratio within the reference values ≥ 1 or ≤2.5, unlike for the CD4/CD8 ratio < 1 and >2.5. The odds ratios for the distribution of CD4+ (OR 5.98, 95% CI 0.001–0.008, p < 0.001), CD8+ (OR 0.23, 95% CI 0.08–0.59, p < 0.01), and CD8CD45RO+ T naïve cells (OR 0.27, 95% CI 0.097–0.695, p < 0.01) and CD4/CD8 (OR 5.69, 95% CI 2.07–17.32, p < 0.001) indicated a potential diagnostic value of T lymphocytes for clinical prognosis in aging-related vascular dysfunction. 相似文献
2.
Yi Sun Yucheng Zhang Yilin Song Eryk Dutkiewicz 《Wireless Personal Communications》2011,60(4):769-807
In recent years, with the development of mobile communication technologies and the increase of available wireless transmission
bandwidth, deploying multimedia services in next generation mobile IPv6 networks has become an inevitable trend. RSVP (resource
reservation protocol) proposed by the IETF is designed for hardwired and fixed networks and can not be used in mobile environments.
This paper proposes a protocol, called Fast RSVP, to reserve resources for mobile IPv6. The protocol adopts a cross-layer
design approach where two modules (RSVP module and Mobile IPv6 module) at different layers cooperate with each other. Fast
RSVP divides a handover process with QoS guarantees into two stages: (1) setup of the resource reservation neighbor tunnel
and (2) resource reservation on the optimized route. It can help a mobile node realize fast handover with QoS guarantees as
well as avoid resource wasting by triangular routes, advanced reservations and duplicate reservations. In addition, fast RSVP
reserves “guard channels” for handover sessions, thus greatly reducing the handover session forced termination rate while
maintaining high performance of the network. Based on extensive performance analysis and simulations, Fast RSVP, compared
with existing methods of resource reservation in mobile environments, performs better in terms of packet delay and throughput
during handover, QoS recovery time after handover, resource reservation cost, handover session forced termination rate and
overall session completion rate. 相似文献
3.
Yuming Ge Min Chen Yi Sun Zhongcheng Li Ying Wang Eryk Dutkiewicz 《Multimedia Tools and Applications》2013,67(1):213-229
The rapid growing of wireless multimedia applications increases the needs of spectrum resources, but today’s spectrum resources have become more and more scarce and large part of the assigned spectrum is in an inefficiency usage. Cognitive Radio (CR) technologies are proposed to solve current spectrum inefficiency problems and offer users a ubiquitous wireless accessing environment, relying on dynamic spectrum allocation. However, there are two unsolved problems in previous work: 1) based on the simplified Quality of Service (QoS) uniform assumption, specific requirements of different wireless multimedia applications cannot be satisfied; 2) aiming at single-objective optimization of spectrum utilization or handoff rate, the co-optimization of these two necessary objectives in CR networks has not been achieved. In this paper, we propose a Two-tier Cooperative Spectrum Allocation method (TCSA) to solve these two problems. TCSA consists of two functional parts: one is a Spectrum Adjacency Ranking algorithm implemented at the secondary users’ terminals to satisfy the QoS requirements for different wireless multimedia applications; and the other is a Max Hyper-weight Matching algorithm implemented at the cognitive engines of CR networks to co-optimize spectrum utilization and secondary users’ spectrum handoff rate. Simulation results show that, compared with the other Random matching algorithm and Cost minimized algorithm, TCSA can significantly improve the performance of CR networks in terms of secondary users’ throughput and spectrum handoff rate. 相似文献
4.
Hao Wen 《计算机科学技术学报》2009,24(3):495-504
IEEE 802.15.4 protocol is proposed to meet the low latency and energy consumption needs in low-rate wireless applications,however,few analytical models are tractable enough for comprehensive evaluation of the protocol.To evaluate the IEEE 802.15.4 slotted CSMA/CA channel access mechanism in this paper,we propose a practical and accurate discrete Markov chain model,which can dynamically represent different network loads.By computing the steady-state distribution probability of the Markov chain,we obtain a... 相似文献
5.
针对无线移动通信的特点,提出了一种在移动IPv6网络中保障用户通信服务质量的资源预留新方案Fast RSVP.该方案采用跨层设计的思想,将两个不同层次的模块:移动IPv6模块和RSVP模块结合起来,通过在两个模块之间增加一些原语使得二者配合工作以保证移动用户的通信业务质量.Fast RSVP方案引入了邻居隧道提前资源预留、优化路径资源预留、切换预留、路径融合等一系列新机制.仿真实验结果表明,与其他移动环境中的RSVP扩展方案相比,该Fast RSVP方案在支持无线移动通信方面具有如下优势:(1)能够实现移动节点带有服务质量保证的快速切换;(2)能够避免移动IP切换过程中三角路由和重复预留造成的资源浪费;(3)能够区分不同类型的切换预留请求,在保证网络整体性能的前提下显著降低因为切换而导致的服务中断率. 相似文献
6.
J. DUTKIEWICZ L. LITYSKA-DOBRZYSKA A. KOVACOVA† . ROGAL & W. MAZIARZ 《Journal of microscopy》2009,236(2):132-136
Amorphous powder of composition corresponding to Ni60Ti20Zr20 (in at%) was obtained by ball milling in a high-energy mills starting from pure elements. Formation of the amorphous structure was observed already after 20 h of milling, although complete amorphization occurred after 40 h. The microhardness of powders increased from about 30 HV for pure elements to above 400 HV (1290 MPa) after 40 h of milling. Transmission electron microscopy (TEM) allowed to identify nanocrystalline inclusions of intermetallic phases of size 2–10 nm. Uniaxial hot pressing was performed in vacuum at temperature below the crystallization Tx it is 510°C and pressure of 600 MPa, Mixed amorphous powders and nanocrystalline silver powders were used to form a composite, in which microhardness was near 970 MPa HV and 400 HV for the amorphous phase and nanocrystalline silver, respectively. The compression strength of the composite containing 20 wt% of nanocrystalline Ag powder was equal to 600 MPa and plastic strain was 2%. Microstructure studies showed low porosity of composites of less than 1%, uniform distribution of the silver phase and a transition zone between both components, about 150 nm thick, where diffusion of nickel, niobium and zirconium into silver was observed. High-resolution TEM allowed identifying the structure of nanocrystalline inclusions in the amorphous matrix after hot pressing as either Ni3 Zr or Ni17 Nb3 . The identification was performed basing on measurements of angles and interatomic distances using inverse Fourier transformed images with enhanced contrast using Digital Micrograph computer program. 相似文献
7.
The structure of Al3Zr precipitates in Al‐1.0Mg‐0.6Si‐0.5Zr (in wt.%) alloy was investigated using conventional transmission electron microscopy (TEM) and high‐resolution TEM (HREM). After annealing of the alloy in the temperature range 450–540 °C, spherical precipitates of metastable L12‐Al3Zr phase appeared nearly homogeneously within the matrix, and elongated particles were found at grain boundaries. L12‐structured Al3Zr were about 20–30 nm in diameter and coherent with the matrix. Inside some of them, planar faults parallel to {100} planes were revealed by use of HREM. Most probably, these faults are an indication of the transition stage of transformation to the stable D023‐type Al3Zr phase. The elongated precipitates (about 100 nm) were identified as D022‐type Al3Zr. Energy‐dispersive X‐ray analysis showed that they contain, apart from Al, mainly Zr with small amounts of Si. The substitution of Al by Si increased the stability of the D022‐Al3Zr as compared with D023‐Al3Zr. 相似文献
8.
Klaudia Sztolsztener Hubert ywno Katarzyna Hodun Katarzyna Konoczuk Katarzyna Muszyska-Rosan Eryk Latoch 《International journal of molecular sciences》2022,23(18)
Patients suffering from childhood acute lymphoblastic leukemia (ALL) are at risk of late adverse treatment-related effects. The examination of targeted biomarkers could be used to improve the diagnosis and prediction of life-threatening ALL sequelae. The purpose of this cross-sectional study was to search for treatment-related alterations in apolipoprotein (Apo) levels as potential markers of the occurrence of obesity in subjects treated for ALL, and to assess the relationships between weight, gender, anticancer treatment, and Apo concentrations. Fifty-eight ALL survivors were included in the study. The mean time of follow-up after treatment cessation was 5.41 ± 4.29 years. Serum levels of apolipoproteins were measured using a multiplex assay kit. Among ALL survivors, we observed a significant correlation of Apo-C1, Apo-C3, Apo-H, and Apo-J levels, depending on body mass index (BMI). Marked differences were observed in the area under the curve of Apo-A1, Apo-A2, Apo-C1, Apo-D. In our study, patients with a history of childhood ALL developed alterations in their Apo profile. Furthermore, this is the first study revealing that some apolipoproteins may act as valuable biomarkers useful in the prognosis of metabolic imbalance. We believe that this paper, at least partially, will highlight the importance of long-term prognosis of metabolic complications associated with the anticancer chemotherapy used to treat hematological malignancies in children. 相似文献
9.
Malignant Ascites Promote Adhesion of Ovarian Cancer Cells to Peritoneal Mesothelium and Fibroblasts
Pawe Uruski Justyna Mikua-Pietrasik Martyna Pakua Sylwia Budkiewicz Marcin Drzewiecki Andrey N. Gaiday Magorzata Wierzowiecka Eryk Naumowicz Rafa Moszyski Andrzej Tykarski Krzysztof Ksiek 《International journal of molecular sciences》2021,22(8)
Although malignant ascites (MAs) are known to contribute to various aspects of ovarian cancer progression, knowledge regarding their role in the adhesion of cancer cells to normal peritoneal cells is incomplete. Here, we compared the effect of MAs and benign ascites (BAs) on the adhesion of A2780 and OVCAR-3 cancer cells to omentum-derived peritoneal mesothelial cells (PMCs) and peritoneal fibroblasts (PFBs). The results showed that MAs stimulated the adhesion of A2780 and OVCAR-3 cells to PMCs and PFBs more efficiently than did BAs, and the strongest binding occurred when both cancer and normal cells were exposed to the fluid. Intervention studies showed that MAs-driven adhesion of A2780 cells to PMCs/PFBs depends on the presence of TGF-β1 and HGF, whereas binding of OVCAR-3 cells was mediated by TGF-β1, GRO-1, and IGF-1. Moreover, MAs upregulated α5β1 integrin expression on PFBs but not on PMCs or cancer cells, vimentin expression in all cells tested, and ICAM-1 only in cancer cells. When integrin-linked kinase was neutralized in PMCs or PFBs, cancer cell adhesion to PMCs and PFBs decreased. Collectively, our report shows that MAs may contribute to the early stages of ovarian cancer metastasis by modulating the proadhesive interplay between normal and cancer cells. 相似文献
10.
Two powder alloys from the β phase region of compositions Co28.5 Ni36.5 Al35 and Co35 Ni30 Al35 were ball milled for 80 h in a high energy ball mill. The formation of amorphous structure was observed after 40 h of milling and further milling did not change their structure. The analytical and high-resolution transmission electron microscopy (TEM, HREM) examination of powder structure showed that nanoparticles of L10 phase of size of about 5 nm were present within the amorphous matrix. The vacuum hot pressing of the milled powders under pressure of 400 MPa at 700°C for 12 min resulted in the formation of compacts with density of about 70% of the theoretical one. The additional heat treatment at 1300°C for 6 h followed by water quenching, led to significant improvement of density and induced the martensitic transformation manifested by a broad heat effect. The characteristic temperatures of the transformation were determined using DSC measurements, which revealed only small differences within the examined alloys compositions. TEM structure studies of heat-treated alloys allowed to identify the structure of an ordered β (B2) phase and L10 martrensite. 相似文献