1,055 research outputs found
Aging-dependent functional alterations of mitochondrial DNA (mtDNA) from human fibroblasts transferred into mtDNA-less cells
To investigate the role that aging-dependent accumulation of mitochondrial DNA (mtDNA) mutations plays in the senescence processes, mitochondria from fibroblasts of 21 normal human individuals between 20 weeks (fetal) and 103 years of age were introduced into human mtDNA-less (ρ0) 206 cells by cytoplast × ρ0 cell fusion, and 7-31 transformant clones were isolated from each fusion. A slight cell donor age-dependent decrease in growth rate was detected in the transformants. Using an O2 consumption rate of 1 fmol/min/cell, which was not observed in any transformant among 158 derived from individuals 20 weeks (fetal) to 37 years of age, as a cut-off to identify respiratory-deficient clones, 11 such clones were found among 198 transformants derived from individuals 39-103 years of age. Furthermore, conventional and nonparametric analysis of the respiratory rates of 356 clones revealed a very significant decrease with donor age. In other analyses, a very significant age-dependent decline in the mtDNA content of the clones was observed, without, however, any significant correlation with the decrease in O2 consumption rate in the defective transformants. These observations clearly indicate the occurrence in the fibroblast-derived transformants of two independent, age-related functional alterations of mtDNA, presumably resulting from structural damage to this genome
Introduction. Traces of Terror, Signs of Trauma
The article introduces a collection of articles about the spatialization processes of memory of war in contemporary Europe. It is divided in three parts. The first part proposes a transdisciplinary perspective, which includes semiotics, to tackle the relations between space, heritage and cultural memory and to analyse memory narratives conveyed by places. An approach based on the investigation of "terrorscapes" (places with a high density of traces) is proposed. The second part delves on the notion of terrorscapes, focusing on the meaning of "terror" and on the shift of paradigm in European politics of memory after 1989. The third part deals with the European space of memory, questioning the possibility of construction of a shared European memory narrative on XX centuries wars. Last paragraph summarizes the contributions of the volume
Stepping Stones Triple P: The theoretical basis and development of an evidence-based positive parenting program for families with a child who has a disability.
Stepping Stones Triple P is the first in a series of programs based on the Triple P – Positive Parenting Program that has been specifically designed for families who have a child with a disability. This paper presents the rationale, theoretical foundations, historical development and distinguishing features of the program. The multi-level intervention adopts a self-regulation framework in consulting with parents that involves the promotion of parental self-sufficiency, selfefficacy, self-management skills, personal agency and problem-solving skills. This paper describes the key program design features, intervention techniques, model of clinical consultation, its clinical applicability, and empirical base. The 10-session individually administered version of the program, known as Standard Stepping Stones Triple P is described and the important role of training, supervision and agency support in disseminating the program is discussed
Are the glasses in mantle xenoliths witness of the metasomatic agent composition?
Glass veins and pockets in mantle xenoliths are often considered as indicators of the composition of metasomatic agents affecting the mantle. Here we demonstrate that infiltration of, and reaction with, the host basalt may produce glassy veins and pockets whose composition encompasses that of different potential metasomatic agents. The xenoliths studied are 4-19 cm large, equigranular, spinel-facies harzburgites and lherzolites from the Patagonia lithospheric mantle. A reaction rim occurs at the contact with the basalt. Peridotite orthopyroxene is in reaction with the basalt and a glassy pocket (up to 600 μm in diameter) is thereby formed. New crystals of euhedral olivine (Fo = 84) and Ti-oxides crystallise in the glass pocket close to the basalt, while euhedral crystals of clinopyroxene (mg# = 85-89) and olivine crystallise close to orthopyroxene. The reaction-crystallisation processes induce dramatic compositional variations in theglass pocket from phonotephryte to trachyte. Trace element concentration and patterns and the element anomalies are controlled by the reaction-crystallisation process. Orthopyroxene dissolution has mainly a dilution effect, whereas clinopyroxene crystallisation and the crystallization of Ti oxides (and apatite) largely controls the trace element fractionation and element anomalies. The largest trace element variations are documented in the veins. The studied glasses obviously do not represent metasomatic agents that affected the lithospheric mantle, but the large compositional variations they document encompass those of glasses quoted in literature (Wulff-Pedersen et al., 1996; Coltorti et al., 2000) and believed to represent metasomatic agents, thus suggesting caution in drawing inferences on mantle processes and components from glass pockets and veins in xenoliths
Life cycle assessment of hydrogen-powered city buses in the High V.LO-City project: integrating vehicle operation and refuelling infrastructure
During the project High V.LO-City, which ended in December 2019, 14 hydrogen fuel cell buses were operated in four European cities. This paper aims at presenting total emissions through the lifetime of fuel cell buses with different hydrogen production options, including the refuelling stations. The environmental assessment of such bus system is carried out using the life cycle assessment methodology. Three hydrogen production pathways are investigated: water electrolysis, chlor-alkali electrolysis and steam methane reforming. Fuel economy during bus operation is around 10.25 KgH2/100 km, and the refuelling station energy demand ranges between 7 and 9 KWh/KgH2. To support the inventory stage, dedicated software tools were developed for collecting and processing a huge amount of bus data and refuelling station performance, for automating data entry and for impacts calculation. The results show that hydrogen-powered buses, compared to a diesel bus, have the potential to reduce emissions during the use phase, if renewables resources are used. On the other hand, impacts from the vehicle production, including battery pack and fuel cell stack, still dominate environmental load. Consequently, improving the emission profile of fuel cell bus system requires to promote clean electricity sources to supply a low-carbon hydrogen and to sharpen policy focus regarding life cycle management and to counter potential setbacks, in particular those related to problem shifting and to grid improvement. For hazardous emissions and resource use, the high energy intensity of mining and refining activities still poses challenges on how to further enhance the environmental advantages of fuel cells and battery packs
Predicting future cancer burden in the United States by artificial neural networks
Aims: To capture the complex relationships between risk factors and cancer incidences in the US and predict future cancer burden. Materials & methods: Two artificial neural network (ANN) algorithms were adopted: a multilayer feed-forward network (MLFFNN) and a nonlinear autoregressive network with eXogenous inputs (NARX). Data on the incidence of the four most common tumors (breast, colorectal, lung and prostate) from 1992 to 2016 (available from National Cancer Institute online datasets) were used for training and validation, and data until 2050 were predicted. Results: The rapid decreasing trend of prostate cancer incidence started in 2010 will continue until 2018–2019; it will then slow down and reach a plateau after 2050, with several differences among ethnicities. The incidence of breast cancer will reach a plateau in 2030, whereas colorectal cancer incidence will reach a minimum value of 35 per 100,000 in 2030. As for lung cancer, the incidence will decrease from 50 per 100,000 (2017) to 31 per 100,000 in 2030 and 26 per 100,000 in 2050. Conclusion: This up-to-date prediction of cancer burden in the US could be a crucial resource for planning and evaluation of cancer-control programs
Androgen Receptor Signaling Pathway in Prostate Cancer: From Genetics to Clinical Applications
Around 80-90% of prostate cancer (PCa) cases are dependent on androgens at initial diagnosis; hence, androgen ablation therapy directed toward a reduction in serum androgens and the inhibition of androgen receptor (AR) is generally the first therapy adopted. However, the patient's response to androgen ablation therapy is variable, and 20-30% of PCa cases become castration resistant (CRPCa). Several mechanisms can guide treatment resistance to anti-AR molecules. In this regard, AR-dependent and -independent resistance mechanisms can be distinguished within the AR pathway. In this article, we investigate the multitude of AR signaling aspects, encompassing the biological structure of AR, current AR-targeted therapies, mechanisms driving resistance to AR, and AR crosstalk with other pathways, in an attempt to provide a comprehensive review for the PCa research community. We also summarize the new anti-AR drugs approved in non-metastatic castration-resistant PCa, in the castration-sensitive setting, and combination therapies with other drugs
Involved margins after lumpectomy for breast cancer: Always to be re-excised?
Background: The oncologic benefit of upfront re-excision of involved margins after breast-conserving surgery in the context of current multimodal clinical management of breast cancer is unclear. The aim of the present study was to assess the 5-years locoregional recurrence (LRR)-free and distant metastases (DM)-free survival probabilities in patients not undergoing re-excision of positive margins after lumpectomy for breast cancer. Methods: A cohort of 104 patients with positive margins not undergoing re-excision was matched by propensity score with a cohort of 2006 control patients with clear margins after breast-conserving surgery, treated between 2008 and 2018. A multivariate survival analysis was performed accounting for all variables related to LRR and DM, including adjuvant treatments. Results: After adjusting for potential confounders, avoiding to re-excise a positive margin after lumpectomy had no effect on 5-years LRR-free survival probability (HR 0.98, 95%CI 0.36-2.67, p = 0.96) or 5-years DM-free survival probability (HR 0.37, 95%CI 0.08-1.61, p = 0.18). No correlation was found between occurrence of LRR and number of involved margins (HR 1.28, 95%CI 0.10-12.4, Log-rank p = 0.83), or extension of infiltrating disease (HR 1.21, 95%CI 0.20-7.40, Log-rank p = 0.83), but a trend toward higher LRR probability was found for invasive ductal (HR 6.92, 95%CI 0.7-68.8, Log-rank p = 0.10) and invasive lobular cancer (HR 12.95, 95%CI 0.79-213.6, Log-rank p = 0.07) on positive margins. Conclusions: In the era of multimodal treatment of breast cancer and accurate strategies to reduce the probability of residual disease in the post-lumpectomy cavity, re-excision of positive margins might be omitted in selected patients with low-risk breast cancers
Physical Prehabilitation in Patients who Underwent Major Abdominal Surgery: A Comprehensive Systematic Review and Component Network Meta-Analysis Using GRADE and CINeMA Approach
Background: Physical prehabilitation is recommended before major abdominal surgery to ameliorate short-term outcomes. Methods: A frequentist, random-effects network meta-analysis (NMA) was performed to clarify which type of preoperative physical activity among aerobic exercise (AE), inspiratory muscle training (IMT), and resistance training produces benefits in patients who underwent major abdominal surgery. The surface under the P-score, odds ratio (OR), or mean difference (MD) with a 95% confidence interval (CI) were reported. The results were adjusted by using the component network approach. The critical endpoints were overall and major morbidity rate and mortality rate. The important but not critical endpoints were the length of stay (LOS) and pneumonia. Results: The meta-analysis included 25 studies. The best approaches for overall morbidity rate were AE and AE + IMT (OR = 0.61, p-score = 0.76, and OR = 0.66, p-score = 0.68). The best approaches for pneumonia were AE + IMT and AE (OR = 0.21, p-score = 0.91, and OR = 0.52, p-score = 0.68). The component analysis confirmed that the best incremental OR (0.30; 95% CI 0.12–0.74) could be obtained using AE + IMT. The best approach for LOS was AE alone (MD − 1.63 days; 95% CI − 3.43 to 0.18). The best combination of components was AE + IMT (MD − 1.70; 95% CI − 2.06 to − 1.27). Conclusions: Physical prehabilitation reduces the overall morbidity rate, pneumonia, and length of stay. The most relevant effect of prehabilitation requires the simultaneous use of AE and IMT
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