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The impact of prior platinum therapy on survival in patients with metastatic urothelial cancer receiving vinflunine
Background: A phase III trial demonstrated an overall survival advantage with the addition of vinflunine to best supportive care (BSC) in platinum-refractory advanced urothelial cancer. We subsequently examined the impact of an additional 2 years of survival follow-up and evaluated the influence of first-line platinum therapy on survival. Methods: The 357 eligible patients from the phase III study were categorised into two cohorts depending on prior cisplatin treatment: cisplatin or non-cisplatin. Survival was calculated using the Kaplan–Meier method. Results: The majority had received prior cisplatin (70.3%). Survival was higher in the cisplatin group (HR: 0.76; CI 95% 0.58–0.99; P=0.04) irrespective of treatment arm. Multivariate analysis including known prognostic factors (liver involvement, haemoglobin, performance status) and prior platinum administration did not show an independent effect of cisplatin. Vinflunine reduced the risk of death by 24% in the cisplatin-group (HR: 0.76; CI 95% 0.58–0.99; P=0.04) and by 35% in non-cisplatin patients (HR: 0.65; CI 95% 0.41–1.04; P=0.07). Interpretation: Differences in prognostic factors between patients who can receive prior cisplatin and those who cannot may explain the survival differences in patients who undergo second line therapy. Prior cisplatin administration did not diminish the subsequent benefit of vinflunine over BSC
<i>mito</i>-QC illuminates mitophagy and mitochondrial architecture <i>in vivo</i>
Autophagic turnover of mitochondria, termed mitophagy, is proposed to be an essential quality-control (QC) mechanism of pathophysiological relevance in mammals. However, if and how mitophagy proceeds within specific cellular subtypes in vivo remains unclear, largely because of a lack of tractable tools and models. To address this, we have developed “mito-QC,” a transgenic mouse with a pH-sensitive fluorescent mitochondrial signal. This allows the assessment of mitophagy and mitochondrial architecture in vivo. Using confocal microscopy, we demonstrate that mito-QC is compatible with classical and contemporary techniques in histochemistry and allows unambiguous in vivo detection of mitophagy and mitochondrial morphology at single-cell resolution within multiple organ systems. Strikingly, our model uncovers highly enriched and differential zones of mitophagy in the developing heart and within specific cells of the adult kidney. mito-QC is an experimentally advantageous tool of broad relevance to cell biology researchers within both discovery-based and translational research communities
Four Interstellar Dust Candidates from the Stardust Interstellar Dust Collector
In January 2006, the Stardust sample return capsule returned to Earth bearing the first solid samples from a primitive solar system body, Comet 81P/Wild2, and a collector dedicated to the capture and return of contemporary interstellar dust. Both collectors were approx. 0.1 sq m in area and were composed of aerogel tiles (85% of the collecting area) and aluminum foils. The Stardust Interstellar Dust Collector (SIDC) was exposed to the interstellar dust stream for a total exposure factor of 20 sq m/day. The Stardust Interstellar Preliminary Examination (ISPE) is a consortium-based project to characterize the collection using nondestructive techniques. The goals and restrictions of the ISPE are described . A summary of analytical techniques is described
Constraining the Origin of Impact Craters on Al Foils from the Stardust Interstellar Dust Collector
Preliminary examination (PE) of the aerogel tiles and Al foils from the Stardust Interstellar Dust Collector has revealed multiple impact features. Some are most likely due to primary impacts of interstellar dust (ISD) grains, and others are associated with secondary impacts of spacecraft debris, and possibly primary impacts of interplanetary dust particles (IDPs) [1, 2]. The current focus of the PE effort is on constraining the origin of the individual impact features so that definitive results from the first direct laboratory analysis of contemporary ISD can be reported. Because crater morphology depends on impacting particle shape and composition, in addition to the angle and direction of impact, unique particle trajectories are not easily determined. However, elemental analysis of the crater residues can distinguish real cosmic dust from the spacecraft debris, due to the low cosmic abundance of many of the elements in the spacecraft materials. We present here results from the elemental analysis of 24 craters and discuss the possible origins of 4 that are identified as candidate ISD impact
Rôle du stress du réticulum endoplasmique et de l'autophagie dans la régulation des réponses immune et angiogénique activées par des stress ischémiques et inflammatoires dans l'épithélium rénal humain
Dans le cadre de situations pathologiques, le rein peut être soumis à de multiples agressions toxiques, ischémiques et immunologiques pouvant favoriser la survenue d une maladie rénale chronique et le développement d une insuffisance rénale. En réponse à ces stress, les cellules du parenchyme rénal vont activer des processus biologiques adaptatifs permettant le maintien de la viabilité cellulaire et l homéostasie de l organe. Ces réponses adaptatives peuvent également activer l immunité innée et induire le remodelage tissulaire (fibrogenèse et angiogenèse). Cependant, les mécanismes précis de cette régulation sont mal connus. L objectif de ce travail a été de caractériser les mécanismes de régulation et les conséquences microenvironnementales (inflammation et angiogenèse) de l activation de la réponse UPR (Unfolded Protein Response) et de l autophagie, en réponse à des stress ischémiques et immunologiques. Dans un premier travail, nous avons montré que la réponse UPR est impliquée dans la génération d une réponse inflammatoire induite par un stress métabolique dans des cellules tubulaires rénales. Le stress métabolique, caractérisé par une carence en glucose, induit un stress du RE et active la réponse UPR. Ce stress active le facteur NF-.B et favorise la transcription de cytokines et chimiokines pro-inflammatoires. La voie PERK/eIF2 : - n est pas nécessaire à l activation de l inflammation mais amplifie l expression des cytokines alors que la voie IRE1 - est impliquée dans la génération de cette réponse inflammatoire. De plus, l ischémie aigue active le stress du RE et l inflammation dans les reins de rat. Enfin, à partir de biopsies de déclampage de greffons rénaux, l expression de GRP78, marqueur du stress du RE, et de NF-.B p65/RelA dans les tubules rénaux, est significativement plus élevée en comparaison avec des biopsies de greffons rénaux stables, à distance de la greffe. Dans un second travail, nous avons montré que la réponse UPR régule l angiogenèse dans les cellules tubulaires rénales lors d une carence en glucose. La voie PERK est un régulateur majeur de l expression des facteurs angiogéniques (VEGFA, bFGF et angiogénine). De plus, l expression de l angiogénine est modulée par les voies PERK et IRE1.. Enfin, l ischémie aigue induite chez le rat, active la réponse UPR parallèlement à l augmentation de l expression de VEGFA, bFGF et de l angiogénine. Dans un troisième travail, nous avons mis en évidence un nouveau mécanisme par lequel l interféron. (IFN.) active l autophagie dans les cellules tubulaires rénales. Nous avons montré que l IFN. entraine une déplétion en tryptophane, active la voie GCN2, une kinase eIF2., ce qui conduit à l augmentation du flux autophagique. De plus, la supplémentation entryptophane et l utilisation d ARN interférence dirigés contre GCN2 inhibent l autophagie induite par l IFN. Enfin, l autophagie intervient dans la régulation de la sécrétion de cytokines inflammatoires et de facteurs de croissance en réponse à l IFN.. En conclusion, nous avons caractérisé dans ce travail des mécanismes originaux de régulation d une réponse inflammatoire et angiogénique par la réponse UPR et l autophagie en réponse à des stress ischémiques et immunologiques au sein de l épithélium tubulaire rénal humain.Under pathological conditions, kidney is subjected to multiple toxic, ischemic and immunological failures that promote the occurrence of chronic kidney disease and the development of acute kidney injury. In response to stress, renal parenchymal cells activate biological adaptive processes permitting the maintenance of cell viability and renal homeostasis. These adaptive responses can also activate innate immunity and induce tissue remodeling (fibrogenesis and angiogenesis). However, accurate mechanisms of this regulation are still unclear. The aim of this work was to characterize regulation mechanisms and micro environmental consequences(inflammation and angiogenesis) of the activation of the UPR (Unfolded Protein Response) and autophagy, in response to ischemic and immunological stress. In a first study, we demonstrated that the UPR is involved in the generation of inflammatory response induces by metabolic stress in tubular renal cells. Metabolic stress, characterized by glucose deprivation, induces an ER stress and activates the UPR. This stress activates NF-.B and promotes the transcription of pro inflammatory cytokines and chemokines. The PERK signaling is not required for the induction of inflammation but amplifies cytokine expression whereas IRE1 is involved in the generation of inflammatory response. Moreover, acute ischemia activates ER stress and inflammation in rat kidneys. Finally, from kidney transplant biopsies performed before implantation, the expression of GRP78, an ER stress marker, and NF-.B p65/RelA in renal tubules is significantly increased in comparison with stable human kidney transplant biopsies. In a second study, we showed that the UPR regulates angiogenesis in tubular renal cells during glucose deprivation. The PERK pathway is a major regulator of angiogenic factors expression (VEGFA, bFGF and angiogenin). Furthermore, angiogenin expression is modulated by PERK and IRE1. pathways. Finally, acute ischemia activates the UPR and, in parallel, increases VEGFA, bFGF and angiogenin expression in rat kidneys. In a third work, we identified a novel mechanism by which IFN. activates autophagy in human kidney epithelial cells. We showed that IFN. promotes tryptophan depletion, activates the eIF2. kinase GCN2, and leads to an increase of the autophagic flux. Moreover, tryptophan supplementation and RNA interference directed against GCN2 inhibit IFN.-induced autophagy. Finally,autophagy regulates the secretion of inflammatory cytokines and growth factors in response to IFN..In conclusion, we characterized in this work original mechanisms that regulate inflammatory and angiogenic responses by the UPR and autophagy in response to ischemic and immunological stress in tubular renal human epithelium.PARIS5-Bibliotheque electronique (751069902) / SudocPARIS-BIUM-Bib. électronique (751069903) / SudocSudocFranceF
Status of the Stardust ISPE and the Origin of Four Interstellar Dust Candidates
Some bulk properties of interstellar dust are known through infrared and X-ray observations of the interstellar medium. However, the properties of individual interstellar dust particles are largely unconstrained, so it is not known whether individual interstellar dust particles can be definitively distinguished from interplanetary dust particles in the Stardust Interstellar Dust Collector (SIDC) based only on chemical, mineralogical or isotopic analyses. It was therefore understood from the beginning of the Stardust Interstellar Preliminary Examination (ISPE) that identification of interstellar dust candidates would rest on three criteria - broad consistency with known extraterrestrial materials, inconsistency with an origin as secondary ejecta from impacts on the spacecraft, and consistency, in a statistical sense, of observed dynamical properties - that is, trajectory and capture speed - with an origin in the interstellar dust stream. Here we quantitatively test four interstellar dust candidates, reported previously [1], against these criteria
Cost-effectiveness of trifluridine/tipiracil for previously treated metastatic colorectal cancer in England and Wales
Background
Treatment options at third-line and beyond for patients with late-line metastatic colorectal cancer (mCRC) are limited, and outcomes are poor with best supportive care (BSC). This study investigated the cost-effectiveness of trifluridine/tipiracil and regorafenib relative to BSC alone in patients with mCRC who have been previously treated with, or are not considered candidates for, standard chemotherapies.
Materials and Methods
A partitioned survival model was constructed to assess the lifetime costs and benefits accrued by patients. Clinical data were derived from the pivotal phase III (Randomized, Double-Blind, Phase 3 Study of TAS-102 plus Best Supportive Care [BSC] versus Placebo plus BSC in Patients with Metastatic Colorectal Cancer Refractory to Standard Chemotherapies [RECOURSE]) and supporting phase II (J003-10040030) randomized controlled trial of trifluridine/tipiracil + BSC versus placebo + BSC, as well as the phase III Colorectal Cancer Treated With Regorafenib or Placebo After Failure of Standard Therapy (CORRECT) randomized controlled trial of regorafenib, and were extrapolated to estimate lifetime outcomes. Costs were taken from published sources, and health effects sourced from previous mCRC studies.
Results
Trifluridine/tipiracil was associated with a 0.27 incremental life year versus BSC alone, which corresponds to a 0.17 quality-adjusted life year gain. The incremental cost of treatment with trifluridine/tipiracil was £8,479, resulting in an incremental cost-effectiveness ratio of £51,194 per quality-adjusted life year gained. Trifluridine/tipiracil was shown to dominate regorafenib (improve outcomes with reduced costs). Sensitivity analyses showed principal areas of uncertainty were survival estimates and patient utility.
Conclusions
The results show that trifluridine/tipiracil is more clinically and cost-effective than regorafenib, with clinical outcomes greatly exceeding those for patients treated with BSC alone. Based on the results of the analysis, trifluridine/tipiracil offers an important new treatment option for patients with mCRC maintaining good performance status at the end of life
A UK cost–effectiveness analysis of trifluridine/tipiracil for heavily pretreated metastatic gastroesophageal cancers
Background: The current work was designed to estimate the cost-effectiveness of trifluridine/tipiracil (T/T) versus best supportive care (BSC) for patients with advanced stage or metastatic gastroesophageal cancer (mGC) from a UK perspective.
Materials & methods: A partitioned survival analysis was undertaken using data from the phase III TAGS trial. A jointly fitted lognormal model was selected for overall survival and individual generalized gamma models were chosen for progression-free survival and time-to-treatment-discontinuation. The primary outcome was the cost per quality-adjusted life year (QALY) gained. Sensitivity analyses were undertaken to investigate uncertainty.
Results: Compared with BSC, T/T was associated with a cost per QALY gained of £37,907.
Conclusion: T/T provides a cost-effective treatment option for mGC in the UK setting
Microanalysis of Hypervelocity Impact Residues of Possible Interstellar Origin
The NASA Stardust spacecraft deployed two collector trays, one dedicated to the collection of dust from Comet Wild 2, and the other for the capture of interstellar dust (ISD). The samples were returned successfully to Earth in 2006, and now provide an unprecedented opportunity for laboratory-based microanalysis of materials from the outer solar system and beyond. Results from the cometary sample studies have demonstrated that Wild 2 contains much more refractory condensate material and much less pristine extra-solar material than expected, which further indicates that there was significant transport of inner solar system materials to the Kuiper Belt in the early solar system [1]. The analysis of the interstellar samples is still in the preliminary examination (PE) phase, due to the level of difficulty in the definitive identification of the ISD features, the overall low abundance, and its irreplaceable nature, which necessitates minimally invasive measurements [2]. We present here coordinated microanalysis of the impact features on the Al foils, which have led to the identification of four impacts that are possibly attributable to interstellar dust. Results from the study of four ISD candidates captured in aerogel are presented elsewhere [2]
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