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The use of power turbines has the advantage of flexible output load adjustment, and is a major configuration of marine gas turbines and aviation turboshaft/turboprop engines. Marine gas turbines and aviation turboshafts and turboprop engines generally have multiple working states and multiple working conditions change laws, which cause the aerodynamic performance of power turbines to fluctuate greatly with changes in working conditions, and different variable working conditions have a severe impact on the turbine loss characteristics. Therefore, it is necessary to deeply understand the internal flow mechanism of power turbines under off-design working conditions in different power turbine application modes, and carry out researches on the design methods of power turbines under wide working conditions. This paper summarizes and analyzes the recent advances in the field of aerodynamics of power turbines for marine and aviation applications. This review covers the following topics that are important for power turbine designs: (1) turbine flow loss prediction models under multiple operating conditions, (2) aerodynamic design and flow mechanism of power turbines for marine gas turbines, (3) aerodynamics of variable speed power turbines for turboshaft/turboprop engines, and (4) other issues about power turbines for marine and turboshaft/turboprop engines. The emphasis is placed on the aerodynamic design and flow mechanism of marine and aviation power turbines. We also present our own insights regarding the current research trends and the prospects for future developments. [ABSTRACT FROM AUTHOR]

The overexpression of P-glycoprotein (P-gp) in tumors leads to multidrug resistance (MDR), which is a significant obstacle in clinical cancer chemotherapy. The co-administration of anticancer drugs and MDR modulators is a promising strategy for overcoming this problem. Our study aimed to explore the reversal mechanism and safety of the MDR modulator LBM-A5 in vitro, and evaluate its pharmacokinetics and effects on doxorubicin metabolism in vivo. We evaluated an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay of anticancer agents mediated by LBM-A5, the effect of LBM-A5 on rhodamine123 intracellular accumulation, and the efflux in K562/DOX cells to investigate the reversal mechanisms of LBM-A5. The results showed that LBM-A5 inhibits rhodamine123 efflux and increases intracellular accumulation by inhibiting the efflux pump function of P-gp. Furthermore, the therapeutic index and CYP3A4 activity analysis in vitro suggested that LBM-A5 is reasonably safe to use. Also, LBM-A5 (10 mg/kg body mass) achieved the required plasma concentration in sufficient time to reverse MDR in vivo. Importantly, the LBM-A5 treatment group shared similar doxorubicin (DOX) pharmacokinetics with the free DOX group. Our results suggest that LBM-A5 effectively reverses MDR ([EC.sub.50] = 483.6 ± 81.7 nmol x [L.sup.-1]) by inhibiting the function of P-gp, with relatively ideal pharmacokinetics and in a safe manner, and so may be a promising candidate for cancer chemotherapy research. Key words: modulator, P-glycoprotein inhibitor, safety. La surexpression de la P-glycoproteine (P-gp) dans les tumeurs conduit a la resistance multiple aux medicaments (MDR, multidrug resistance), le principal obstacle a la chimiotherapie du cancer. L'administration conjointe de medicaments anticancereux et de modulateurs de la MDR constitue une strategie prometteuse pour surmonter ce probleme. Cette etude visait a explorer le mecanisme de renversement et l'inocuite d'un modulateur de la MDR, le LBM-A5, in vitro, et a evaluer sa pharmacocinetique et son effet sur le metabolisme de la doxorubicine in vivo. Un dosage par MTT de l'effet du LBM-A5 sur les agents anti-cancereux, l'accumulation intracellulaire de rhodamine 123 et son efflux dans les cellules K562/DOX ont ete mesures afin d'examiner les mecanismes de renversement du LBM-A5. Les resultats ont montre que le LBM-A5 pouvait inhiber l'efflux de rhodamine 123 et accroitre son accumulation intracellulaire en inhibant la pompe d'efflux P-gp. De plus, l'indice therapeutique et l'analyse de l'activite du CYP3A4 in vitro suggeraient que le LBM-A5 presentait une inocuite acceptable. En outre, le LBM-A5 a une dose de 10 mg-(kg de masse corporelle)-1 pouvait atteindre la concentration plasmatique requise et avait suffisamment de temps pour renverser la MDR in vivo. Fait important, la pharmacocinetique de la DOX du groupe traite au LBM-A5 etait la meme que celle du groupe DOX libre. Les resultats des auteurs suggerent que le LBM-A5 peut renverser efficacement la MDR (C[E.sub.50] = 483,6 ± 81,7 nmol x [L.sup.-1]) en inhibant la fonction de P-gp avec une pharmacocinetique relativement ideale et de maniere securitaire, et de ce fait, qu'il pourrait devenir un bon candidat dans le domaine de la recherche en chimiotherapie du cancer. [Traduit par la Redaction] Mots-cles: modulateur, inhibiteur de la P-glycoproteine, securite., Introduction Cancer is a life-threatening disease worldwide that cannot be ignored. However, successful chemotherapy in cancer patients has always been hindered by the phenomenon of multidrug resistance (MDR), which is [...]

This study provided a new method to in vitro evaluate the biocompatibility of nanoscaled scaffolds for tissue engineering with neutrophils other than ordinary cell culture. The neutrophils were separated from human peripheral blood of healthy subjects. In vitro degradation product of nanohydroxyapatite/collagen (nHAC), nanohydroxyapatite/collagen/poly (L-lactic acid) (nHACP), and nHACP reinforced by chitin fibers (nHACP/CF) in the D-Hank's Balanced Salt Solution (D-HBSS) was used as the testing solution, which was thereafter mixed with the neutrophils. It was shown that the cell survival rate in the testing solutions had no significant difference from that in the D-HBSS (control). However, from both gene and protein expression levels, the lactate dehydrogenase and tumor necrosis factor-alpha of the neutrophils in the nHACP/CF testing solution were found lowest during the whole testing period; the main reasons of which might be that the calcium release rate of the scaffold was slowest and that the pH value of its degradation solution was nearest to that of human body. Moreover, in vivo experiments showed that most inflammation reactions happened for nHAC and poly (L-lactic acid) groups, while the least inflammation reactions happened for nHACP/CF group in the subcutaneous dorsum of mice at 2 weeks after the surgery, which confirmed the in vitro findings. These results indicated that the pH value and the certain metal iron concentration of the nanoscaled scaffold degradation solution should be two important factors that significantly affect its biocompatibility. This study provides a simple and effective biocompatibility test method for biodegradable nanoscaled tissue engineering scaffolds. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2117-2125, 2016. [ABSTRACT FROM AUTHOR]

As their name suggests, conductive nanomaterials (CNMs) are a type of functional materials, which not only have a high surface area to volume ratio, but also possess excellent conductivity. Thus far, CNMs have been widely used in biomedical applications, such as effectively transferring electrical signals, and providing a large surface area to adsorb proteins and induce cellular functions. Recent works propose further applications of CNMs in biosensors, tissue engineering, neural probes, and drug delivery. This review focuses on common types of CNMs and elaborates on their unique properties, which indicate that such CNMs have a potential to develop into a class of indispensable biomaterials for the diagnosis and therapy of human diseases. [ABSTRACT FROM AUTHOR]

The transfer of regulatory information between distal loci on chromatin is thought to involve physical proximity, but key biophysical features of these contacts remain unclear. For instance, it is unknown how close and for how long two loci need to be in order to productively interact. The main challenge is that it is currently impossible to measure chromatin dynamics with high spatiotemporal resolution at scale. Polymer simulations provide an accessible and rigorous way to test biophysical models of chromatin regulation, yet there is a lack of simple and general methods for extracting the values of model parameters. Here we adapt the Nelder-Mead simplex optimization algorithm to select the best polymer model matching a given Hi-C dataset, using the MYC locus as an example. The model's biophysical parameters predict a compartmental rearrangement of the MYC locus in leukemia, which we validate with single-cell measurements. Leveraging trajectories predicted by the model, we find that loci with similar Hi-C contact frequencies can exhibit widely different contact dynamics. Interestingly, the frequency of productive interactions between loci exhibits a non-linear relationship with their Hi-C contact frequency when we enforce a specific capture radius and contact duration. These observations are consistent with recent experimental observations and suggest that the dynamic ensemble of chromatin configurations, rather than average contact matrices, is required to fully predict productive long-range chromatin interactions.

P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) is a major obstacle for successful cancer chemotherapy. Based on our previous study, 17 novel compounds with the 6,7-dimethoxy-2-{2-[4-(1H-1,2,3-triazol-1-yl)phenyl]ethyl}-1,2,3,4-tetrahydroisoquinoline scaffold were designed and synthesized. Among them, 2-[(1-{4-[2-(6,7-dimethoxy-3,4-dihydroisoquinolin-2(1H)-yl)ethyl]phenyl}-1H-1,2,3-triazol-4-yl)methoxy]-N-(p-tolyl)benzamide (compound 7 h) was identified as a potent modulator of P-gp-mediated MDR, with high potency (EC50 =127.5 ± 9.1 nM), low cytotoxicity (TI>784.3), and long duration (>24 h) in reversing doxorubicin (DOX) resistance in K562/A02 cells. Compound 7 h also enhanced the effects of other MDR-related cytotoxic agents (paclitaxel, vinblastine, and daunorubicin), increased the accumulation of DOX and blocked P-gp-mediated rhodamine 123 efflux function in K562/A02 MDR cells. Moreover, 7 h did not have any effect on cytochrome (CYP3A4) activity. These results indicate that 7 h is a relatively safe modulator of P-gp-mediated MDR that has good potential for further development., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)