Promising Complementary Strategy Research Articles

From binary to multicomponent photoactive layer: A promising complementary strategy to efficient hybrid solar cells

A strategy is demonstrated for fabrication of highly efficient hybrid solar cells based on the polymer/nanoarrays with complementary multicomponents in photoactive layer, including a scenario to controllably synthesize ternary ZnO/CdS/Sb2S3–core/shell/shell nanoarrays (ZCS–NAs) for a high open-circuit voltage (Voc) and short-circuit current and an approach to dope amorphous polymer with lithium bis(trifluoromethanesulfonyl) amide at nanoscale for a remarkably improved fill factor. With the integrated benefits from the complementary multicomponents having optimized nanoarray structure and doping concentration, an efficiency up to 5.01% under AM 1.5 illumination (100mW/cm2) is achieved in the polymer/ZCS–NA devices with poly(2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene) as the polymer. To the best of our knowledge, this is the highest efficiency in the polymer/nanoarray devices. It is found that the Voc in the multicomponent solar cells is determined by the band level difference between ZnO core and polymer, and sufficient photo-excitation of the polymer is necessary for efficient photocurrent generation. The component effects on device performance are elucidated and a model concerning the effective polymer phase and illumination attenuation between nanorods is proposed for understanding the charge generation from polymer absorption in the multicomponent solar cells.

Circulating tumor cells as early predictors of metastatic spread in breast cancer patients with limited metastatic dissemination.

IntroductionTraditional factors currently used for prognostic stratification do not always adequately predict treatment response and disease evolution in advanced breast cancer patients. Therefore, the use of blood-based markers, such as circulating tumor cells (CTCs), represents a promising complementary strategy for disease monitoring. In this retrospective study, we explored the role of CTC counts as predictors of disease evolution in breast cancer patients with limited metastatic dissemination.MethodsA total of 492 advanced breast cancer patients who had a CTC count assessed by CellSearch prior to starting a new line of systemic therapy were eligible for this analysis. Using the threshold of 5 CTCs/7.5 ml of blood, pretreatment CTC counts were correlated in the overall population with metastatic site distribution, evaluated at baseline and at the time of treatment failure, using Fisher’s exact test. Time to visceral progression and time to the development of new metastatic lesions and sites were estimated in patients with nonvisceral metastases and with single-site metastatic disease, respectively, by the Kaplan-Meier method. Survival times were compared between groups according to pretreatment CTC count by logrank test.ResultsIn the overall population, a pretreatment level ≥5 CTCs/7.5 ml was associated with an increased baseline number of metastatic sites compared with <5 CTCs/7.5 ml (P = 0.0077). At the time of treatment failure, patients with ≥5 CTCs/7.5 ml more frequently developed new metastatic lesions and sites compared with those with <5 CTCs/7.5 ml (development of new lesions: P = 0.0002; development of new sites: P = 0.0031). Among patients with disease originally confined to nonvisceral sites, ≥5 CTCs/7.5 ml was associated with remarkably shorter time to visceral metastases (P = 0.0021) and overall survival (P = 0.0006) compared with <5 CTCs/7.5 ml. In patients with single-site metastatic disease, ≥5 CTCs/7.5 ml was associated with a significant reduction of the time to development of new metastatic sites (P = 0.0051) and new lesions (P = 0.0002) and with worse overall survival (P = 0.0101).ConclusionOur results suggest that baseline CTC counts can be used as an early predictor of metastatic potential in breast cancer patients with limited metastatic dissemination.Electronic supplementary materialThe online version of this article (doi:10.1186/s13058-014-0440-8) contains supplementary material, which is available to authorized users.

Functional Identification of Neural Stem Cell–Derived Oligodendrocytes by Means of Calcium Transients Elicited by Thrombin

Current immunosuppressive treatments for central nervous system demyelinating diseases fail to prevent long-term motor and cognitive decline in patients. Excitingly, glial cell transplantation arises as a promising complementary strategy to challenge oligodendrocytes loss occurring in myelination disorders. A potential source of new oligodendrocytes is the subventricular zone (SVZ) pool of multipotent neural stem cells. However, this approach has been handicapped by the lack of functional methods for identification and pharmacological analysis of differentiating oligodendrocytes, prior to transplantation. In this study, we questioned whether SVZ-derived oligodendrocytes could be functionally discriminated due to intracellular calcium level ([Ca(2+)](i)) variations following KCl, histamine, and thrombin stimulations. Previously, we have shown that SVZ-derived neurons and immature cells can be discriminated on the basis of their selective [Ca(2+)](i) rise upon KCl and histamine stimulation, respectively. Herein, we demonstrate that O4+ and proteolipid protein-positive (PLP+) oligodendrocytes do not respond to these stimuli, but display a robust [Ca(2+)](i) rise following thrombin stimulation, whereas other cell types are thrombin-insensitive. Thrombin-induced Ca(2+) increase in oligodendrocytes is mediated by protease-activated receptor-1 (PAR-1) activation and downstream signaling through G(q/11) and phospholipase C (PLC), resulting in Ca(2+) recruitment from intracellular compartments. This method allows the analysis of functional properties of oligodendrocytes in living SVZ cultures, which is of major interest for the development of effective grafting strategies in the demyelinated brain. Additionally, it opens new perspectives for the search of new pro-oligodendrogenic factors to be used prior grafting.

Thrombin-induced intracellular calcium rise identifies oligodendrocytes derived from SVZ cultures

Event Abstract Back to Event Thrombin-induced intracellular calcium rise identifies oligodendrocytes derived from SVZ cultures S. Grade1*, F Agasse1, L-Bernardino C. Gomes1 and Joao O. Malva1 1 University of Coimbra, Center for Neuroscience and Cell Biology, Portugal Glial cell transplantation arises as a promising complementary strategy to challenge oligodendrocytes loss occurring in the demyelinated brain. Recent advances in stem cell biology, namely concerning subventricular zone (SVZ) stem cells have been giving new hopes offering a source of new oligodendrocytes for cell replenishment in MS brains. However, there are yet no good methods for the functional identification of differentiating oligodendrocytes, and pharmacological analysis in these cells prior transplantation.In the present study, we questioned whether SVZ-derived oligodendrocytes could be functionally discriminated on the basis of variations of intracellular calcium levels ([Ca2+]i) following 50 mM KCl, 100 μM histamine or 0,1 U/ml thrombin stimulations. For this purpose, P1-3 C57/BL6 mice SVZ cultures were treated with triiodo-L-thyronine (T3) to promote oligodendrocytic differentiation before functional analysis of the heterogeneous population. Our group has previously shown that SVZ-derived neurons and immature cells can be discriminated due to their selective [Ca2+]i rise upon KCl and histamine stimulations, respectively. Herein, we demonstrate that O4-oligodendrocytes, as observed previously in astrocytes, do not respond to these stimuli. Nonetheless, O4-oligodendrocytes display an increase in [Ca2+]i following thrombin stimulation whereas all the other cell types in the culture were insensitive to thrombin. Thus, oligodendrocytes can be distinguished according to the uniqueness of their response to thrombin.We further show that thrombin-induced calcium increase in SVZ-derived oligodendrocytes is mediated by protease-activated receptor-1 activation with the downstream involvement of Gq/11 and PLC, resulting in the mobilization of calcium from the cellular internal stores.This method allows the analysis of functional properties of the oligodendrocytic cell population in living SVZ cultures which is of major interest for the development of efficient grafting strategies in the demyelinated brain. Furthermore, this technique opens new perspectives for the search of new pro-oligodendrogenic factors to be used prior grafting. Ackowledgments:PTDC/SAU-NEU/68465/2006, FEDER Conference: 11th Meeting of the Portuguese Society for Neuroscience, Braga, Portugal, 4 Jun - 6 Jun, 2009. Presentation Type: Oral Presentation Topic: Symposium 4 – Neuroregeneration Strategies Citation: Grade S, Agasse F, Gomes LC and Malva JO (2009). Thrombin-induced intracellular calcium rise identifies oligodendrocytes derived from SVZ cultures. Front. Neurosci. Conference Abstract: 11th Meeting of the Portuguese Society for Neuroscience. doi: 10.3389/conf.neuro.01.2009.11.014 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 05 Aug 2009; Published Online: 05 Aug 2009. * Correspondence: S. Grade, University of Coimbra, Center for Neuroscience and Cell Biology, Alicante, Portugal, jomalva@fmed.uc.pt Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers S. Grade F Agasse L-Bernardino C Gomes Joao O Malva Google S. Grade F Agasse L-Bernardino C Gomes Joao O Malva Google Scholar S. Grade F Agasse L-Bernardino C Gomes Joao O Malva PubMed S. Grade F Agasse L-Bernardino C Gomes Joao O Malva Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.