485 research outputs found
Identification of a set of widely expressed genes in grape (Vitis vinifera L.) and its functional characterisation: a multi-evidence based study
Quantitative gene expression data analysis requires efficient normalization to be really informative: as a consequence reference genes that are stably expressed in tested vs. control samples are used for results standardization. The identification of tissue-wide-expressed genes makes it easier to highlight the best set of candidate internal controls. While tissue-specific genes are often regulated by microRNA, housekeeping genes, being involved in cell maintenance and thus required in all miRNA expressing cells are not expected to be microRNA targets. In this work we have identified a set of tissue-wide expressed genes in grape which has then been functionally characterised and scanned for the presence vs. absence of putative miRNA target sites. The gene list obtained by this multi-evidence based procedure can be helpful to identify appropriate references in grape.
Energy relaxation in disordered charge and spin density waves
We investigate collective effects in the strong pinning model of disordered
charge and spin density waves (CDWs and SDWs) in connection with heat
relaxation experiments. We discuss the classical and quantum limits that
contribute to two distinct contribution to the specific heat (a contribution and a contribution respectively),
with two different types of disorder (strong pinning versus substitutional
impurities). From the calculation of the two level system energy splitting
distribution in the classical limit we find no slow relaxation in the
commensurate case and a broad spectrum of relaxation times in the
incommensurate case. In the commensurate case quantum effects restore a non
vanishing energy relaxation, and generate stronger disorder effects in
incommensurate systems. For substitutional disorder we obtain Friedel
oscillations of bound states close to the Fermi energy. With negligible
interchain couplings this explains the power-law specific heat observed in experiments on CDWs and SDWs combined to the power-law
susceptibility observed in the CDW o-TaS.Comment: 13 pages, 10 figures, improvements in the presentatio
Wood chemotaxonomy via ESI-MS profiles of phytochemical markers: the challenging case of african versus brazilian mahogany woods
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The harvesting of Brazilian mahogany (Swietenia macrophylla) is a main cause of the Brazilian Amazon deforestation and has been therefore prohibited. African mahogany (Khaya ivorensis) was then introduced for Amazon reforestation and the commercialization of such wood is legal, thus creating a challenging problem for wood certification. Herein we report that a wood chemotaxonomic method based on distinct profiles of phytochemical markers is able to promptly characterize both the native and foreign mahogany species. This challenging task has been performed via a simple, fast and unambiguous methodology using direct electrospray ionization mass spectrometry (ESI-MS) analysis of a simple methanolic extract of a tiny wood chip. Typical limonoids such as khivorin, khayanolide A and mexicanolide for African mahogany and phragmalin-type limonoids for the native Brazilian species, as well as distinct polyphenols such as catechin derivatives and cinchonain, form the characteristic phytochemical marker pools for both species. This rapid methodology could therefore be used to monitor legal and illegal mahogany tree harvesting, and hence to control Amazon deforestation. It could also be applied to create a wood certification program for African and Brazilian mahogany trees, as well as for wood certification in general.The harvesting of Brazilian mahogany (Swietenia macrophylla) is a main cause of the Brazilian Amazon deforestation and has been therefore prohibited. African mahogany (Khaya ivorensis) was then introduced for Amazon reforestation and the commercialization72085768583FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFINEP - FINANCIADORA DE ESTUDOS E PROJETOSFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)sem informaçãosem informaçãosem informaçã
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
Memory Effects in Granular Material
We present a combined experimental and theoretical study of memory effects in
vibration-induced compaction of granular materials. In particular, the response
of the system to an abrupt change in shaking intensity is measured. At short
times after the perturbation a granular analog of aging in glasses is observed.
Using a simple two-state model, we are able to explain this short-time
response.
We also discuss the possibility for the system to obey an approximate
pseudo-fluctuation-dissipation theorem relationship and relate our work to
earlier experimental and theoretical studies of the problem.Comment: 5 pages, 4 figures, reference list change
Cognitive reserve in granulin-related frontotemporal dementia: from preclinical to clinical stages
OBJECTIVE
Consistent with the cognitive reserve hypothesis, higher education and occupation attainments may help persons with neurodegenerative dementias to better withstand neuropathology before developing cognitive impairment. We tested here the cognitive reserve hypothesis in patients with frontotemporal dementia (FTD), with or without pathogenetic granulin mutations (GRN+ and GRN-), and in presymptomatic GRN mutation carriers (aGRN+).
METHODS
Education and occupation attainments were assessed and combined to define Reserve Index (RI) in 32 FTD patients, i.e. 12 GRN+ and 20 GRN-, and in 17 aGRN+. Changes in functional connectivity were estimated by resting state fMRI, focusing on the salience network (SN), executive network (EN) and bilateral frontoparietal networks (FPNs). Cognitive status was measured by FTD-modified Clinical Dementia Rating Scale.
RESULTS
In FTD patients higher level of premorbid cognitive reserve was associated with reduced connectivity within the SN and the EN. EN was more involved in FTD patients without GRN mutations, while SN was more affected in GRN pathology. In aGRN+, cognitive reserve was associated with reduced SN.
CONCLUSIONS
This study suggests that cognitive reserve modulates functional connectivity in patients with FTD, even in monogenic disease. In GRN inherited FTD, cognitive reserve mechanisms operate even in presymptomatic to clinical stages
Mean-field theory of temperature cycling experiments in spin-glasses
We study analytically the effect of temperature cyclings in mean-field
spin-glasses. In accordance with real experiments, we obtain a strong
reinitialization of the dynamics on decreasing the temperature combined with
memory effects when the original high temperature is restored. The same
calculation applied to mean-field models of structural glasses shows no such
reinitialization, again in accordance with experiments. In this context, we
derive some relations between experimentally accessible quantities and propose
new experimental protocols. Finally, we briefly discuss the effect of field
cyclings during isothermal aging.Comment: Some misprints corrected, references updated, final version to apper
in PR
Toward a Glutamate Hypothesis of Frontotemporal Dementia
Frontotemporal dementia (FTD) is a heterogenous neurodegenerative disorder, characterized by diverse clinical presentations, neuropathological characteristics and underlying genetic causes. Emerging evidence has shown that FTD is characterized by a series of changes in several neurotransmitter systems, including serotonin, dopamine, GABA and, above all, glutamate. Indeed, several studies have now provided preclinical and clinical evidence that glutamate is key in the pathogenesis of FTD. Animal models of FTD have shown a selective hypofunction in N-methyl D-aspartate (NMDA) and \u3b1-amino-3-hydroxyl-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, while in patients, glutamatergic pyramidal neurons are depleted in several areas, including the frontal and temporal cortices. Recently, a selective involvement of the AMPA GluA3 subunit has been observed in patients with autoimmune anti-GluA3 antibodies, which accounted for nearly 25% of FTD patients, leading to a decrease of the GluA3 subunit synaptic localization of the AMPA receptor and loss of dendritic spines. Other in vivo evidence of the involvement of the glutamatergic system in FTD derives from non-invasive brain stimulation studies using transcranial magnetic stimulation, in which specific stimulation protocols have indirectly identified a selective and prominent impairment in glutamatergic circuits in patients with both sporadic and genetic FTD. In view of limited disease modifying therapies to slow or revert disease progression in FTD, an important approach could consist in targeting the neurotransmitter deficits, similarly to what has been achieved in Parkinson's disease with dopaminergic therapy or Alzheimer's disease with cholinergic therapy. In this review, we summarize the current evidence concerning the involvement of the glutamatergic system in FTD, suggesting the development of new therapeutic strategies
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