Throughout life, neural stem cells (NSCs) generate neurons in the mammalian brain. Using photobleaching experiments, we found that during cell division in vitro and within the developing mouse ...forebrain, NSCs generate a lateral diffusion barrier in the membrane of the endoplasmic reticulum, thereby promoting asymmetric segregation of cellular components. The diffusion barrier weakens with age and in response to impairment of lamin-associated nuclear envelope constituents. Weakening of the diffusion barrier disrupts asymmetric segregation of damaged proteins, a product of aging. Damaged proteins are asymmetrically inherited by the nonstem daughter cell in embryonic and young adult NSC divisions, whereas in the older adult brain, damaged proteins are more symmetrically distributed between progeny. Thus, these data identify a mechanism of how damage that accumulates with age is asymmetrically distributed during somatic stem cell division.
The prevalence of hepatopulmonary syndrome (HPS) and its influence on survival before and after liver transplantation (LT) remain controversial. Additionally, the chronology of post‐LT reversibility ...is unclear. This study prospectively analyzed 316 patients with cirrhosis who were evaluated for LT in 2002–2007; 177 underwent LT at a single reference hospital. HPS was defined by a partial pressure of arterial oxygen (PaO2) <70 mmHg and/or an alveolar‐arterial oxygen gradient (A‐a PO2) ≥20 mmHg in the supine position and positive contrast echocardiography. The prevalence of HPS was 25.6% (81/316 patients), and most patients (92.6%) had mild or moderate HPS. High Child‐Pugh scores and the presence of ascites were independently associated with HPS. Patients with and without HPS did not significantly differ in LT waiting list survival (mean 34.6 months vs. 41.6 months, respectively; log‐rank, p = 0.13) or post‐LT survival (mean 45 months vs. 47.6 months, respectively; log‐rank, p = 0.62). HPS was reversed in all cases within 1 year after LT. One‐fourth of the patients with cirrhosis who were evaluated for LT had HPS (mostly mild to moderate); the presence of HPS did not affect LT waiting list survival. HPS was always reversed after LT, and patient prognosis did not worsen.
This prospective study investigates hepatopulmonary syndrome in cirrhotic patients evaluated for liver transplantation, finding a 25% prevalence, mostly mild or moderate, without any influence on the waiting list and posttransplantation survival and with reversibility in all cases after transplant.
Textual agency Gomez-Bravo, Ann M
Textual agency,
2013, 20131211, 2013, 2014, 2013-01-01, 2013-12-11
eBook
Gómez-Bravo also explores how authorial and textual agency were competing forces in the midst of an era marked by the institution of the Inquisition, the advent of the absolutist state, the growth of ...cities, and the constitution of the Spanish nation.
Loss of oxygen in the global ocean is accelerating due to climate change and eutrophication, but how acute deoxygenation events affect tropical marine ecosystems remains poorly understood. Here we ...integrate analyses of coral reef benthic communities with microbial community sequencing to show how a deoxygenation event rapidly altered benthic community composition and microbial assemblages in a shallow tropical reef ecosystem. Conditions associated with the event precipitated coral bleaching and mass mortality, causing a 50% loss of live coral and a shift in the benthic community that persisted a year later. Conversely, the unique taxonomic and functional profile of hypoxia-associated microbes rapidly reverted to a normoxic assemblage one month after the event. The decoupling of ecological trajectories among these major functional groups following an acute event emphasizes the need to incorporate deoxygenation as an emerging stressor into coral reef research and management plans to combat escalating threats to reef persistence.
Transitional metals have a large variety of coordination numbers and geometries, accessible redox states in physiological conditions and a wide range of thermodynamic and reactivity properties which ...can be successfully tuned by selection of suitable ligands. These characteristics can be used to develop new drugs with numerous advantages over the organic based drugs. Historically, research in this field has focus on platinum and DNA targeting; however, anticancer drug research may be expanded to include alternative metal compounds with different mode of action resulting in markedly different cytotoxic response profiles. Cooper complexes with selected ligands are being extensively studied as agents for the treatment of cancer. Current research on copper compounds as antitumoral compounds is being reviewed in this chapter particularly focused on the family of copper Casiopeinas.
Cancer is the second cause of death worldwide, surpassed only by cardiovascular diseases, due to the lack of early diagnosis, and high relapse rate after conventional therapies. Chemotherapy inhibits ...the rapid growth of cancer cells, but it also affects normal cells with fast proliferation rate. Therefore, it is imperative to develop other safe and more effective treatment strategies, such as gene therapy, in order to significantly improve the survival rate and life expectancy of patients with cancer. The aim of gene therapy is to transfect a therapeutic gene into the host cells to express itself and cause a beneficial biological effect. However, the efficacy of the proposed strategies has been insufficient for delivering the full potential of gene therapy in the clinic. The type of delivery vehicle (viral or non viral) chosen depends on the desired specificity of the gene therapy. The first gene therapy trials were performed with therapeutic genes driven by viral promoters such as the CMV promoter, which induces non-specific toxicity in normal cells and tissues, in addition to cancer cells. The use of tumor-specific promoters over-expressed in the tumor, induces specific expression of therapeutic genes in a given tumor, increasing their localized activity. Several cancer- and/or tumor-specific promoters systems have been developed to target cancer cells. This review aims to provide up-to-date information concerning targeting gene therapy with cancer- and/or tumor-specific promoters including cancer suppressor genes, suicide genes, anti-tumor angiogenesis, gene silencing, and gene-editing technology, as well as the type of delivery vehicle employed. Gene therapy can be used to complement traditional therapies to provide more effective treatments.
Mitochondria-associated membranes (MAMs) are structures that regulate physiological functions between endoplasmic reticulum (ER) and mitochondria in order to maintain calcium signaling and ...mitochondrial biogenesis. Several proteins located in MAMs, including those encoded by
PARK
genes and some of neurodegeneration-related proteins (huntingtin, presenilin, etc.), ensure this regulation. In this regard, MAM alteration is associated with neurodegenerative diseases such as Parkinson’s (PD), Alzheimer’s (AD), and Huntington’s diseases (HD) and contributes to the appearance of the pathogenesis features, i.e., autophagy dysregulation, mitochondrial dysfunction, oxidative stress, and lately, neuronal death. Moreover,, ER stress and/or damaged mitochondria can be the cause of these disruptions. Therefore, ER-mitochondria contact structure and function are crucial to multiple cellular processes. This review is focused on the molecular interaction between ER and mitochondria indispensable to MAM formation and on MAM alteration-induced etiology of neurodegenerative diseases.
Background
Psoriasis is a very prevalent systemic chronic inflammatory disease. Major cardiovascular events are the main cause of mortality in these patients which suggests an association between ...psoriasis and traditional cardiovascular risk factors.
Objective
To identify classic cardiovascular risk factors and metabolic syndrome (MS) in patients with psoriasis, their possible association with its severity and compare it with the non‐psoriatic population.
Methods
This is an observational and cross‐sectional population study in Lleida (Spain) from a joint hospital/primary care database.
Results
The database comprised 398 701 individuals. There were 6868 cases registered as psoriasis (1.7%), and 499 of them (7.3%) were classified as moderate–severe psoriasis. Patients with psoriasis had a higher prevalence of traditional cardiovascular risk factors than non‐psoriatic population: diabetes mellitus 2 (13.9% vs 7.4%, OR 2.01), dyslipidaemia (28.8% vs 17.4%, OR 1.92), arterial hypertension (31.2% vs 19.0%, OR 1.93), obesity (33.7% vs 28.1%, OR 1.30), altered fasting basal glycaemia (21.4% vs 15.1%, OR 1.54), low cholesterol HDL (38.1% vs 32.3%, OR 1.29), hypertriglyceridaemia (45.7% vs 35.2%, OR 1.55) and high waist circumference (75.7% vs 72.3%, OR 1.19). MS was more prevalent in psoriatic patients (28.3% vs 15.1%, OR 2.21), and cardiovascular risk factors were similar between psoriasis severity groups. Psoriatic patients had a higher prevalence of ischaemic heart disease (3.3% vs 1.8%, OR 1.87) and vascular cerebral accidents (1.8% vs 1.2%, OR 1.55). A model for MS showed a significant nonlinear relationship with age and sex and significant differences between patients with and without psoriasis.
Conclusion
We found statistically significant differences in relation to the prevalence of cardiovascular risk factors, MS and major cardiovascular events in psoriatic patients. However, differences were not seen between psoriasis severity groups. Our work reinforces the need for a multidisciplinary approach and close monitoring of cardiovascular risk factors in these patients to prevent a cardiovascular event.
•Four different untreated CDW sources.•Influence of CDW composition on the performance of polycarboxylic superplasticizers.•Superplasticizer effect on workability, compressive and tensile strengths, ...and Young’s modulus.•Recycled aggregate characteristics limit the efficiency of superplasticizers.•Superplasticizers lose efficiency when used with CDW aggregates instead of concrete waste.
Most research on recycled aggregates concrete concern aggregates produced from concrete waste, rather than actual construction and demolition waste. Different investigations have assessed that sulfonated-based superplastizers are not as efficient in recycled aggregates concrete than on natural aggregates concrete, but no significant loss of polycarboxylic-based superplasticizer efficiency has been reported. This may not be valid when the aggregates are sourced from actual construction and demolition waste, due to the higher porosity, roughness, and weaker mechanical properties of aggregates produced from this source. This paper analyses the mechanical properties of superplasticized concrete with the incorporation of construction and demolition waste. Recycled aggregates produced from construction and demolition waste were taken directly from plants and used as aggregates without screening or treatment, emulating what would happen in a practical application by the concrete industry. The results of the tests and the superplasticizer’s efficiency are compared with results on natural aggregate concrete compositions and on analogue recycled concrete aggregate concrete compositions with and without superplasticizers. The composition of the different construction and demolition waste aggregates is considered during the analysis of results. Evidence was found that when recycled aggregates are sourced from construction and demolition waste, polycarboxylic-based superplasticizers perform satisfactorily but may not be as efficient as in natural aggregate concrete compositions.
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