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101.
102.
Behnaz Valipour Kobra Velaei Ali Abedelahi Mohammad Karimipour Masoud Darabi Hojjatollah Nozad Charoudeh 《Journal of cellular physiology》2019,234(11):19352-19365
Natural killer (NK) cells have significant capability in tumor immune-surveillance. The ability of lyse transformed cells immediately in an antigen-independent manner make them an attractive candidate for cancer cell therapy. Despite employment of NK cells in cancer immunotherapy, clinical trials are faced with serious limitations such as trouble with the penetration of NK cells in tumor sites, limited in vivo persistence, and tumor microenvironment interference. Taken together, the NK-cell cancer therapy is still infant scenario that has a long way to be translated in clinic. Current article first reviews characteristic features of NK lymphocytes. Then, it discusses about important disruptive barriers and motivator in the developmental stages of NK cells like as tumor microenvironment. Finally, some revolutionary approaches are highlighted utilizing of NK cells in cancer therapy. 相似文献
103.
H V?rsmann F Groeber H Walles S Busch S Beissert H Walczak D Kulms 《Cell death & disease》2013,4(7):e719
Despite remarkable efforts, metastatic melanoma (MM) still presents with significant mortality. Recently, mono-chemotherapies are increasingly replenished by more cancer-specific combination therapies involving death ligands and drugs interfering with cell signaling. Still, MM remains a fatal disease because tumors rapidly develop resistance to novel therapies thereby regaining tumorigenic capacity. Although genetically engineered mouse models for MM have been developed, at present no model is available that reliably mimics the human disease and is suitable for studying mechanisms of therapeutic obstacles including cell death resistance. To improve the increasing requests on new therapeutic alternatives, reliable human screening models are demanded that translate the findings from basic cellular research into clinical applications. By developing an organotypic full skin equivalent, harboring melanoma tumor spheroids of defined sizes we have invented a cell-based model that recapitulates both the 3D organization and multicellular complexity of an organ/tumor in vivo but at the same time accommodates systematic experimental intervention. By extending our previous findings on melanoma cell sensitization toward TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) by co-application of sublethal doses of ultraviolet-B radiation (UVB) or cisplatin, we show significant differences in the therapeutical outcome to exist between regular two-dimensional (2D) and complex in vivo-like 3D models. Of note, while both treatment combinations killed the same cancer cell lines in 2D culture, skin equivalent-embedded melanoma spheroids are potently killed by TRAIL+cisplatin treatment but remain almost unaffected by the TRAIL+UVB combination. Consequently, we have established an organotypic human skin-melanoma model that will facilitate efforts to improve therapeutic outcomes for malignant melanoma by providing a platform for the investigation of cytotoxic treatments and tailored therapies in a more physiological setting. 相似文献
104.
The interrelation of Alpine topography with the micro − and mesobiota is still poorly understood. We investigated the effects of ground cover type and slope exposure on the soil microbial biomass (double-stranded DNA, dsDNA) and abundances (real time PCR, qPCR); hydrolytic enzyme activities; and enchytraeid community structure in top soils (2.5-cm increments depth) in subalpine forests in the Italian Alps. Dominant ground covers were grass, moss, litter and woody debris at the north- and the south-facing slopes. The autochthonous soil microbiota (bacteria, fungi and archaea) was quantified by qPCR in the extracellular (eDNA) and intracellular fraction (iDNA) of the total soil DNA pool. A higher eDNA/iDNA ratio indicative of lower microbial activity was recorded in the deepest layer of the grass plots at the north-facing slope. This can be related to a lower degradation of eDNA and/or to an accumulation of eDNA with increasing depth as a result of leaching. The exposure effect was enzyme-specific and higher activities occurred under woody debris primarily at the south-facing slope. These plots also showed a higher nutrient content and a greater microbial biomass assessed as dsDNA yields. Total microannelid abundance was elevated on north-facing slopes on account of strong acidity indicator species. This was related to soil pH being one unit lower compared to the south-facing slope. The thickness of the organic layer (OL + OF + OH) was elevated at the north-facing slope due to a considerably thicker OH-horizon. The vast majority of microannelids at this slope occurred in the organic layer, while at south exposure they were almost evenly distributed between the organic layer and the mineral soil (A-horizon). Exposure was found to be more determinative for the composition of microannelid assemblages than the ground cover type. 相似文献
105.
Regenerative medicine is a burgeoning field that is important to combat challenging diseases and functional impairments. Compared with traditional cell therapies with evident shortcomings (e.g., cell suspension injection or tissue engineering with scaffolds), scaffold-free cell sheet technology enables transplanted cells to be grafted and fully maintain their viability on target sites. Clinical and experimental studies have advanced the application of cell sheet technology to numerous tissues and organs (e.g., liver, cornea and bone). However, previous reviews have failed to discuss vital aspects of this rapidly developing technology, and many new challenges are gradually emerging. This review aims to provide a comprehensive introduction to cell sheet technology from cell selection to the ultimate applications of cell sheets, and challenges and future visions are also described. 相似文献
106.
107.
《Process Biochemistry》2014,49(6):973-980
The pseudo-capacitive behaviour of a high surface area carbon veil electrode in a tubular microbial fuel cell (MFC) was investigated as a mechanism to enhance power quality and energy efficiency. Accumulated charge and energy from the anodic biofilm after prolonged open circuit times (1–120 min) were compared against equivalent periods of steady state loading (R = 100–3000 Ω). A significant difference in the amount of accumulated charge with different loads was observed, resulting in 1.051 C (R = 100 Ω) compared to 0.006 C (R = 3 kΩ). The automated application of short open and closed circuit (0.5–10 s) cycles resulted in an increase of power/current production (closed circuit alone), but presented lower efficiency considering entire open and closed period. The cumulative charge on the carbon veil electrode with biofilm was 39,807 C m−2 at 100 Ω. Electrochemical Impedance Spectroscopy (EIS) showed that the Helmholtz layer presented a double layer capacitance of more than ten times the biofilm on electrode. The results indicate that the capacitive behaviour could be utilized to increase the power quality, i.e. its availability/applicability with respect to the operation of low power consuming devices. 相似文献
108.
Genetically modified cells of Pseudomonas fluorescens, chromosomally marked with genes for bioluminescence, were inoculated into sterile soil microcosms. During incubation for 90 days, viable cell concentration did not change significantly but light output, measured by luminometry, decreased, indicating reduced metabolic activity due to lack of substrates. Amendment with nutrients resulted in parallel increases in both luminescence and dehydrogenase activity. Luminometry therefore enables rapid monitoring of the activity of populations of luminescence-marked microbial inocula in the soil, with greater sensitivity and selectivity than traditional techniques. 相似文献
109.
Arash Salmaninejad Saeed Farajzadeh Valilou Arezoo Gowhari Shabgah Saeed Aslani Malihe Alimardani Alireza Pasdar Amirhossein Sahebkar 《Journal of cellular physiology》2019,234(10):16824-16837
Over the course of past few years, cancer immunotherapy has been accompanied with promising results. However, preliminary investigations with respect to immunotherapy concentrated mostly on targeting the immune checkpoints, nowadays, emerge as the most efficient strategy to raise beneficial antitumor immune responses. Programmed cell death protein 1 (PD-1) plays an important role in subsiding immune responses and promoting self-tolerance through suppressing the activity of T cells and promoting differentiation of regulatory T cells. PD-1 is considered as an immune checkpoint and protects against autoimmune responses through both induction of apoptosis in antigen-specific T cells and inhibiting apoptosis in regulatory T cells. Several clinical trials exerting PD-1 monoclonal antibodies as well as other immune-checkpoint blockades have had prosperous outcomes and opened new horizons in tumor immunotherapy. Nonetheless, a bulk of patients have failed to respond to these newly emerging immune-based approach and the survival rate was not satisfying. Additional strategies, especially combination therapies, has been initiated and been further promising. Attempts to identify novel and well-suited predictive biomarkers are also sensed. In this review, the promotion of cancer immunotherapy targeting PD-1 immunoinhibitory pathway is discussed. 相似文献
110.
In this study CdS-Ag2S nanocomposites for antibacterial activity were synthesized via facile co-precipitation method using PVP as capping agent. The prepared nanocomposites have particle sizes in the range of 50–100 nm (SEM) and PVP addition has good influence on the morphology of nanocomposites. The antimicrobial activity of pure Ag2S, CdS and CdS-Ag2S composites was evaluated against Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli. The results demonstrate that antibacterial activity was significantly improved due to increasing ratio of CdS into CdS-Ag2S nanocomposites in comparison to pure Ag2S and CdS. 相似文献