172 research outputs found

    Water stress during the post-harvest period affects new root formation but not starch concentration and content in Chardonnay grapevine (Vitis vinifera L.) perennial organs

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    Water stress responses during the post-harvest period were evaluated in a Chardonnay container-grown grapevines grafted onto 1103 Paulsen rootstock. The irrigation treatments were: a control treatment (C) (irrigated to match ETC demands) and a water stress treatment (WS) (irrigated when midday stem water potential reached a -1.1 MPa threshold). Photosynthesis, biomass and carbohydrate content were determined on five vines in each treatment on specific dates, from harvest until leaf fall. Stressed vines reduced leaf area due to defoliation, while well-watered vines had a higher carbon accumulation allowing the formation of new roots during the post-harvest period. No dry biomass accumulation was observed in the shoot and trunk organs after fruit harvest. Starch concentration and content were not affected by water stress. At the end of the experiment, starch concentrations were lower in the shoots and trunk than in the roots. Water stress induced a variation on biomass accumulation between above and below ground perennial organs, with the roots being the main organs in which biomass and starch concentrations were accumulated and kept, respectively.info:eu-repo/semantics/acceptedVersio

    Post-Harvest Regulated Deficit Irrigation in Chardonnay Did Not Reduce Yield but at Long-Term, It Could Affect Berry Composition

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    Future increases in temperatures are expected to advance grapevine phenology and shift ripening to warmer months, leaving a longer post-harvest period with warmer temperatures. Accumulation of carbohydrates occurs during post-harvest, and has an influence on vegetative growth and yield in the following growing season. This study addressed the possibility of adopting regulated deficit irrigation (RDI) during post-harvest in Chardonnay. Four irrigation treatments during post-harvest were applied over three consecutive seasons: (i) control (C), with full irrigation; (ii) low regulated deficit irrigation for sparkling base wine production (RDIL SP), from harvest date of sparkling base wine, irrigation when stem water potential (Ψstem) was less than −0.9 MPa; (iii) mild regulated deficit irrigation for sparkling base wine production (RDIM SP), from harvest date of sparkling base wine, irrigation when Ψstem was less than −1.25 MPa; (iv) mild regulated deficit irrigation for wine production (RDIM W), from harvest data of wine, irrigation when Ψstem was less than −1.25 MPa. Root starch concentration in full irrigation was higher than under RDI. Yield parameters did not differ between treatments, but differences in berry composition were detected. Considering that the desirable berry composition attributes of white varieties are high in titratable acidity, it would seem inappropriate to adopt RDI strategy during post-harvest. However, in a scenario of water restriction, it may be considered because there was less impact on yield and berry composition than if RDI had been adopted during pre-harvest.info:eu-repo/semantics/publishedVersio

    Anatomical Laser Microdissection of the Ileum Reveals mtDNA Depletion Recovery in A Mitochondrial Neuro-Gastrointestinal Encephalomyopathy (MNGIE) Patient Receiving Liver Transplant

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    Microanatomical dissection; Mitochondrial disorders; MtDNA depletionDisección microanatómica; Trastornos mitocondriales; Agotamiento del ADNmtDissecció microanatòmica; Trastorns mitocondrials; Esgotament de l'ADNmtMitochondrial neuro-gastrointestinal encephalomyopathy (MNGIE) is a rare genetic disorder characterized by thymidine phosphorylase (TP) enzyme defect. The absence of TP activity induces the imbalance of mitochondrial nucleotide pool, leading to impaired mitochondrial DNA (mtDNA) replication and depletion. Since mtDNA is required to ensure oxidative phosphorylation, metabolically active tissues may not achieve sufficient energy production. The only effective life-saving approach in MNGIE has been the permanent replacement of TP via allogeneic hematopoietic stem cell or liver transplantation. However, the follow-up of transplanted patients showed that gut tissue changes do not revert and fatal complications, such as massive gastrointestinal bleeding, can occur. The purpose of this study was to clarify whether the reintroduction of TP after transplant can recover mtDNA copy number in a normal range. Using laser capture microdissection and droplet-digital-PCR, we assessed the mtDNA copy number in each layer of full-thickness ileal samples of a naive MNGIE cohort vs. controls and in a patient pre- and post-TP replacement. The treatment led to a significant recovery of gut tissue mtDNA amount, thus showing its efficacy. Our results indicate that a timely TP replacement is needed to maximize therapeutic success before irreversible degenerative tissue changes occur in MNGIE.The work was supported by Ministero dell’Istruzione, dell’Università e della Ricerca-Dipartimenti eccellenti on the Project Personalized medicine. LC and VC are supported by the Italian Ministry of Health (Ricerca Corrente 2021 funding). RDG is supported by funds from the University of Ferrara

    Long proleptic and sylleptic shoots in peach (Prunus persica L. Batsch) trees have similar, predetermined, maximum numbers of nodes and bud fate patterns

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    Background and Aims In peach (Prunus persica) trees, three types of shoots can be distinguished depending on the time of their appearance: sylleptic, proleptic and epicormic. On proleptic shoots, an average of ten phytomers are preformed in dormant buds prior to shoot growth after bud-break, whereas all phytomers are considered neoformed in sylleptic and epicormic shoots. However, casual observations indicated that proleptic and sylleptic shoots appear quite similar in number of phytomers and structure in spite of their different origins. The goal of this research was to test the hypothesis that both proleptic and sylleptic shoots exhibit similar growth characteristics by analysing their node numbers and bud fate patterns. If their growth characteristics are similar, it would indicate that the structure of both types of shoots is primarily under genetic rather than environmental control. Methods The number of phytomers and bud fate patterns of proleptic and sylleptic shoots of four peach cultivars grown in the same location (Winters, California) were analysed and characterized using hidden semi-Markov models. Field data were collected during winter 2016, just prior to floral bud-break. Key Results Sylleptic shoots tended to have slightly fewer phytomers than proleptic shoots of the same cultivars. The bud fate patterns along proleptic and sylleptic shoots were remarkably similar for all the cultivars, although proleptic shoots started growing earlier (at least 1 month) in the spring than sylleptic shoots. Conclusions This study provides strong evidence for the semi-deterministic nature of both proleptic and sylleptic shoots across four peach cultivars in terms of number of phytomers and bud fate patterns along shoots. It is apparent that the overall structure of shoots with similar numbers of phytomers was under similar genetic control for the two shoot types. Understanding shoot structural characteristics can aid in phenotypic characterization of vegetative growth of trees and in providing a foundation for vegetative management of fruit trees in horticultural settings.info:eu-repo/semantics/acceptedVersio

    Neural encoding of voice pitch and formant structure at birth as revealed by frequency-following responses

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    Detailed neural encoding of voice pitch and formant structure plays a crucial role in speech perception, and is of key importance for an appropriate acquisition of the phonetic repertoire in infants since birth. However, the extent to what newborns are capable of extracting pitch and formant structure information from the temporal envelope and the temporal fine structure of speech sounds, respectively, remains unclear. Here, we recorded the frequency-following response (FFR) elicited by a novel two-vowel, rising-pitch-ending stimulus to simultaneously characterize voice pitch and formant structure encoding accuracy in a sample of neonates and adults. Data revealed that newborns tracked changes in voice pitch reliably and no differently than adults, but exhibited weaker signatures of formant structure encoding, particularly at higher formant frequency ranges. Thus, our results indicate a well-developed encoding of voice pitch at birth, while formant structure representation is maturing in a frequency-dependent manner. Furthermore, we demonstrate the feasibility to assess voice pitch and formant structure encoding within clinical evaluation times in a hospital setting, and suggest the possibility to use this novel stimulus as a tool for longitudinal developmental studies of the auditory system

    Structural and functional analysis of tomato sterol C22 desaturase

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    Background: Sterols are structural and functional components of eukaryotic cell membranes. Plants produce a complex mixture of sterols, among which β-sitosterol, stigmasterol, campesterol, and cholesterol in some Solanaceae, are the most abundant species. Many reports have shown that the stigmasterol to β-sitosterol ratio changes during plant development and in response to stresses, suggesting that it may play a role in the regulation of these processes. In tomato (Solanum lycopersicum), changes in the stigmasterol to β-sitosterol ratio correlate with the induction of the only gene encoding sterol C22-desaturase (C22DES), the enzyme specifically involved in the conversion of β-sitosterol to stigmasterol. However, despite the biological interest of this enzyme, there is still a lack of knowledge about several relevant aspects related to its structure and function. Results: In this study we report the subcellular localization of tomato C22DES in the endoplasmic reticulum (ER) based on confocal fluorescence microscopy and cell fractionation analyses. Modeling studies have also revealed that C22DES consists of two well-differentiated domains: a single N-terminal transmembrane-helix domain (TMH) anchored in the ER-membrane and a globular (or catalytic) domain that is oriented towards the cytosol. Although TMH is sufficient for the targeting and retention of the enzyme in the ER, the globular domain may also interact and be retained in the ER in the absence of the N-terminal transmembrane domain. The observation that a truncated version of C22DES lacking the TMH is enzymatically inactive revealed that the N-terminal membrane domain is essential for enzyme activity. The in silico analysis of the TMH region of plant C22DES revealed several structural features that could be involved in substrate recognition and binding. Conclusions: Overall, this study contributes to expand the current knowledge on the structure and function of plant C22DES and to unveil novel aspects related to plant sterol metabolism

    Effects of impaired steryl ester biosynthesis on tomato growth and developmental processes

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    Steryl esters (SE) are stored in cytoplasmic lipid droplets and serve as a reservoir of sterols that helps to maintain free sterols (FS) homeostasis in cell membranes throughout plant growth and development, and provides the FS needed to meet the high demand of these key plasma membrane components during rapid plant organ growth and expansion. SE are also involved in the recycling of sterols and fatty acids released from membranes during plant tissues senescence. SE are synthesized by sterol acyltransferases, which catalyze the transfer of long-chain fatty acid groups to the hydroxyl group at C3 position of FS. Depending on the donor substrate, these enzymes are called acyl-CoA:sterol acyltransferases (ASAT), when the substrate is a long-chain acyl-CoA, and phospholipid:sterol acyltransferases (PSAT), which use a phospholipid as a donor substrate. We have recently identified and preliminary characterized the tomato (Solanum lycopersicum cv. Micro-Tom) SlASAT1 and SlPSAT1 enzymes. To gain further insight into the biological role of these enzymes and SE biosynthesis in tomato, we generated and characterized CRISPR/Cas9 single knock-out mutants lacking SlPSAT1 (slpsat1) and SlASAT1 (slasat1), as well as the double mutant slpsat1 x slasat1. Analysis of FS and SE profiles in seeds and leaves of the single and double mutants revealed a strong depletion of SE in slpsat1, that was even more pronounced in the slpsat1 x slasat1 mutant, while an increase of SE levels was observed in slasat1. Moreover, SlPSAT1 and SlASAT1 inactivation affected in different ways several important cellular and physiological processes, like leaf lipid bo1dies formation, seed germination speed, leaf senescence, and the plant size. Altogether, our results indicate that SlPSAT1 has a predominant role in tomato SE biosynthesis while SlASAT1 would mainly regulate the flux of the sterol pathway. It is also worth to mention that some of the metabolic and physiological responses in the tomato mutants lacking functional SlPSAT1 or SlASAT1 are different from those previously reported in Arabidopsis, being remarkable the synergistic effect of SlASAT1 inactivation in the absence of a functional SlPSAT1 on the early germination and premature senescence phenotypes

    The frequency-following response in late preterm neonates: a pilot study

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    IntroductionInfants born very early preterm are at high risk of language delays. However, less is known about the consequences of late prematurity. Hence, the aim of the present study is to characterize the neural encoding of speech sounds in late preterm neonates in comparison with those born at term.MethodsThe speech-evoked frequency-following response (FFR) was recorded to a consonant-vowel stimulus /da/ in 36 neonates in three different groups: 12 preterm neonates [mean gestational age (GA) 36.05 weeks], 12 “early term neonates” (mean GA 38.3 weeks), and “late term neonates” (mean GA 41.01 weeks).ResultsFrom the FFR recordings, a delayed neural response and a weaker stimulus F0 encoding in premature neonates compared to neonates born at term was observed. No differences in the response time onset nor in stimulus F0 encoding were observed between the two groups of neonates born at term. No differences between the three groups were observed in the neural encoding of the stimulus temporal fine structure.DiscussionThese results highlight alterations in the neural encoding of speech sounds related to prematurity, which were present for the stimulus F0 but not for its temporal fine structure

    Programa de Formació CONECTEM. Comunicació Bàsica i Assistida amb el malalt crític

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    El programa que es presenta, va dirigit principalment a les infermeres que tracten amb pacients crítics (urgències, emergències i unitats de cures intensives). Aquest programa consisteix en donar eines i recursos a les infermeres per poder-se comunicar de manera efectiva amb aquest tipus de malalts, que sovint per les seves condicions de salut presenten dificultats alhora de comunicar-se. La comunicació efectiva entre la infermera i el pacient promou la qualitat de l’atenció de les cures infermeres al pacient crític, millorant el pronòstic i l’evolució dels malalts i disminuïnt les possibles conseqüències psico-emocionals derivades de la seva situació
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