The dynamics of embolism refilling in abscisic acid (ABA)-deficient tomato plants.

Plants are in danger of embolism formation in xylem vessels when the balance between water transport capacity and transpirational demand is compromised. To maintain this delicate balance, plants must regulate the rate of transpiration and, if necessary, restore water transport in embolized vessels. Abscisic acid (ABA) is the dominant long-distance signal responsible for plant response to stress, and it is possible that it plays a role in the embolism/refilling cycle. To test this idea, a temporal analysis of embolism and refilling dynamics, transpiration rate and starch content was performed on ABA-deficient mutant tomato plants. ABA-deficient mutants were more vulnerable to embolism formation than wild-type plants, and application of exogenous ABA had no effect on vulnerability. However, mutant plants treated with exogenous ABA had lower stomatal conductance and reduced starch content in the xylem parenchyma cells. The lower starch content could have an indirect effect on the plant's refilling activity. The results confirm that plants with high starch content (moderately stressed mutant plants) were more likely to recover from loss of water transport capacity than plants with low starch content (mutant plants with application of exogenous ABA) or plants experiencing severe water stress. This study demonstrates that ABA most likely does not play any direct role in embolism refilling, but through the modulation of carbohydrate content, it could influence the plant's capacity for refilling

Genetic structure of gilthead seabream, Sparus aurata, in the Central Mediterranean Sea

Abstract The gilthead seabream, Sparus aurata, represents an important economic resource for Mediterranean aquaculture. In spite of its wide geographic distribution and economic importance, only recently studies have been carried out on the genetic composition of natural populations, which have revealed a picture of a heterogeneous degree of genetic differentiation among S. aurata populations. In this study an allozyme analysis of samples from six different collecting sites along the Italian and Croatian coasts was carried out, covering an area in the Central Mediterranean sea that has yet to be investigated through gene-enzyme systems. Data on 26 gene loci, 10 of which are polymorphic, indicate a slight but significant genetic structure (FST = 0.0167) of the species. A hierarchical analysis of population subdivision made it possible to identify three different assemblages found in the Adriatic Sea, Tyrrhenian Sea and Sardinian Channel, though an isolation by distance model can be rejected. The results are discussed in the light of previous literature and taking conservation into consideration

Bioactive Phenolic Compounds in the Modulation of Central and Peripheral Nervous System Cancers: Facts and Misdeeds.

Efficacious therapies are not available for the cure of both gliomas and glioneuronal tumors, which represent the most numerous and heterogeneous primary cancers of the central nervous system (CNS), and for neoplasms of the peripheral nervous system (PNS), which can be divided into benign tumors, mainly represented by schwannomas and neurofibromas, and malignant tumors of the peripheral nerve sheath (MPNST). Increased cellular oxidative stress and other metabolic aspects have been reported as potential etiologies in the nervous system tumors. Thus polyphenols have been tested as effective natural compounds likely useful for the prevention and therapy of this group of neoplasms, because of their antioxidant and anti-inflammatory activity. However, polyphenols show poor intestinal absorption due to individual intestinal microbiota content, poor bioavailability, and difficulty in passing the blood–brain barrier (BBB). Recently, polymeric nanoparticle-based polyphenol delivery improved their gastrointestinal absorption, their bioavailability, and entry into defined target organs. Herein, we summarize recent findings about the primary polyphenols employed for nervous system tumor prevention and treatment. We describe the limitations of their application in clinical practice and the new strategies aimed at enhancing their bioavailability and targeted delivery. © 2020 by the authors

Chromosome 16p11.2 deletions: another piece in the genetic puzzle of childhood obesity

Ipercaloric diet and reduced physical activity have driven the rise in the prevalence of childhood obesity over a relatively short time interval. Family and twin studies have led to the conclusion that the strong predicitve value of parental body mass index (BMI) mainly stems from genetic rather than environmental factors. Whereas the common polygenic obesity arises when an individual genetic make-up is susceptible to an environment that promotes energy consumption over energy expenditure, monogenic obesity, on the contrary, is the obesity associated with a single gene mutation, which is sufficient by itself to cause weight gain in a food abundant context. Genes involved in the leptin-melanocortin pathway are often mutated in these cases. The cumulative prevalence of monogenic obesity among children with severe obesity is about 5%

REFLEXÕES E APONTAMENTOS DA EDUCAÇÃO MATEMÁTICA NUMA PERSPECTIVA HISTÓRICO-CULTURAL

Esta pesquisa baseia-se em experiências já realizadas no ensino de conteúdos de Matemática numa perspectiva Histórico-Cultural que evidenciem que a construção de conhecimento matemático acontece num processo de apropriação de significados e nas relações sociais onde são requeridos.A partir da realização do levantamento e dos resultados obtidos, observamos que existe uma significativa ampliação da aproximação em experiências de ensino de conteúdos matemáticos que seguem esta perspectiva, em diferentes contextos e momentos da Educação Básica que discutimos e apresentamos neste trabalho

Severe ocular involvement in a newborn with Langerhans Cell Histiocytosis

Abstract Langerhans Cell Histiocytosis (LCH) is a rare proliferative disease of the mononuclear phagocyte system, characterised by tissue infiltration of CD1a + CD207+ histiocytes. The clinical presentation is variable, ranging from unifocal asymptomatic bone involvement to life-threatening multisystem disease, requiring aggressive therapeutic approaches. Intraocular involvement is uncommon and associated to poor visual and general prognosis. We report a case of LCH in a newborn with severe ocular and multisystem risk-organ involvement, unresponsive to several lines of chemotherapy. Off-label administration of vemurafenib led to dramatic improvement at systemic level; however, chronic sequelae of ocular involvement resulted in poor visual prognosis. Intraocular LCH involvement may be asymptomatic and clinical signs delayed, leading to severe complications, especially in newborns and young children. Screening for ocular involvement is essential for early treatment initiation, which can possibly improve the visual outcome. Vemurafenib is effective on systemic involvement, and its role in ocular LCH needs to be evaluated

Current practice of iron prophylaxis in preterm and low birth weight neonates: A survey among Italian Neonatal Units.

Background: Preterm babies are at high risk of iron deficiency. Methods: We investigated current practices regarding iron prophylaxis in preterm and low birth weight newborns among Local Neonatal Units (LNUs, n = 74) and Neonatal Intensive Care Units (NICUs, n = 20) of three Italian Regions (Piemonte, Marche and Lazio). Results: Birth weight is considered an indicative parameter in only 64% of LNUs and 71% of NICUs, with a significant difference between LNUs in the three regions (86%, 20% and 62%, respectively; p < 0.001). Iron is recommended to infants with a birth weight between 2000 and 2500 g in only 25% of LNUs and 21% of NICUs, and to late-preterm (gestational age between 34 and 37 weeks) in a minority of Units (26% of LNUs, 7% of NICUs). Conclusions: Our pilot survey documents a great variability and the urgent need to standardize practices according to literature recommendations. Key Words: iron, iron deficiency anemia, newborn, preterm, prophylaxi