New perspective for the upscaling of plant functional response to flooding stress in salt marshes using remote sensing

Understanding the response of salt marshes to flooding is crucial to foresee the fate of these fragile ecosystems, requiring an upscaling approach. In this study we related plant species and community response to multispectral indices aiming at parsing the power of remote sensing to detect the environmental stress due to flooding in lagoon salt marshes. We studied the response of Salicornia fruticosa (L.) L. and associated plant community along a flooding and soil texture gradient in nine lagoon salt marshes in northern Italy. We considered community (i.e., species richness, dry biomass, plant height, dry matter content) and individual traits (i.e., annual growth, pigments, and secondary metabolites) to analyze the effect of flooding depth and its interplay with soil properties. We also carried out a drone multispectral survey, to obtain remote sensing-derived vegetation indices for the upscaling of plant responses to flooding. Plant diversity, biomass and growth all declined as inundation depth increased. The increase of soil clay content exacerbated flooding stress shaping S. fruticosa growth and physiological responses. Multispectral indices were negatively related with flooding depth. We found key species traits rather than other community traits to better explain the variance of multispectral indices. In particular stem length and pigment content (i.e., betacyanin, carotenoids) were more effective than other community traits to predict the spectral indices in an upscaling perspective of salt marsh response to flooding. We proved multispectral indices to potentially capture plant growth and plant eco-physiological responses to flooding at the large scale. These results represent a first fundamental step to establish long term spatial monitoring of marsh acclimation to sea level rise with remote sensing. We further stressed the importance to focus on key species traits as mediators of the entire ecosystem changes, in an ecological upscaling perspective.

Intraspecific variability of leaf form and function across habitat types

Trait-based ecology has already revealed main independent axes of trait variation defining trait spaces that summarize plant adaptive strategies, but often ignoring intraspecific trait variability (ITV). By using empirical ITV-level data for two independent dimensions of leaf form and function and 167 species across five habitat types (coastal dunes, forests, grasslands, heathlands, wetlands) in the Italian peninsula, we found that ITV: (i) rotated the axes of trait variation that define the trait space; (ii) increased the variance explained by these axes and (iii) affected the functional structure of the target trait space. However, the magnitude of these effects was rather small and depended on the trait and habitat type. Our results reinforce the idea that ITV is context-dependent, calling for careful extrapolations of ITV patterns across traits and spatial scales. Importantly, our study provides a framework that can be used to start integrating ITV into trait space analyses.

Characterisation and functionalisation of chitosan nanoparticles as carriers for double-stranded RNA (dsRNA) molecules towards sustainable crop protection

The need to minimise the impact of phytosanitary treatments for disease control boosted researchers to implement techniques with less environmental impact. The development of technologies using molecular mechanisms based on the modulation of metabolism by short dsRNA sequences appears promising. The intrinsic fragility of polynucleotides and the high cost of these techniques can be circumvented by nanocarriers that protect the bioactive molecule enabling high efficiency delivery to the leaf surface and extending its half-life. In this work, a specific protocol was developed aiming to assess the best methodological conditions for the synthesis of low-size chitosan nanoparticles (NPs) to be loaded with nucleotides. In particular, NPs have been functionalised with partially purified Green Fluorescent Protein dsRNAs (GFP dsRNA) and their size, surface charge and nucleotide retention capacity were analysed. Final NPs were also stained with FITC and sprayed on Nicotiana benthamiana leaves to assess, by confocal microscopy, both a distribution protocol and the fate of NPs up to 6 days after application. Finally, to confirm the ability of NPs to increase the efficacy of dsRNA interference, specific tests were performed: by means of GFP dsRNA-functionalised NPs, the nucleotide permanence during time was assessed both in vitro on detached wild-type N. benthamiana leaves and in planta; lastly, the inhibition of Botrytis cinerea on single leaves was also evaluated, using a specific fungal sequence (Bc dsRNA) as the NPs' functionalising agent. The encouraging results obtained are promising in the perspective of long-lasting application of innovative treatments based on gene silencing.

Contrasting Responses of Two Grapevine Cultivars to Drought: The Role of Non-structural Carbohydrates in Xylem Hydraulic Recovery

Xylem embolism is one of the possible outcomes of decreasing xylem pressure when plants face drought. Recent studies have proposed a role for non-structural carbohydrates (NSCs) in osmotic pressure generation, required for refilling embolized conduits. Potted cuttings of grapevine Grenache and Barbera, selected for their adaptation to different climatic conditions, were subjected to a drought stress followed by re-irrigation. Stem embolism rate and its recovery were monitored in vivo by X-ray micro-computed tomography (micro-CT). The same plants were further analyzed for xylem conduit dimension and NSC content. Both cultivars significantly decreased Ψpd in response to drought and recovered from xylem embolism after re-irrigation. However, although the mean vessel diameter was similar between the cultivars, Barbera was more prone to embolism. Surprisingly, vessel diameter was apparently reduced during recovery in this cultivar. Hydraulic recovery was linked to sugar content in both cultivars, showing a positive relationship between soluble NSCs and the degree of xylem embolism. However, when starch and sucrose concentrations were considered separately, the relationships showed cultivar-specific and contrasting trends. We showed that the two cultivars adopted different NSC-use strategies in response to drought, suggesting two possible scenarios driving conduit refilling. In Grenache, sucrose accumulation seems to be directly linked to embolism formation and possibly sustains refilling. In Barbera, maltose/maltodextrins could be involved in a conduit recovery strategy via the formation of cell-wall hydrogels, likely responsible for the reduction of conduit lumen detected by micro-CT.

Antifungal activity of chili pepper extract with potential for the control of some major pathogens in grapevine

BACKGROUND

In recent years, biofungicides have drawn increasing interest in vineyards for a more sustainable integrated and copper-limited pest management. Among alternatives, botanicals could represent valuable tools, being rich sources of biologically active compounds. Conversely to the well-known antioxidant and biological properties in relation to health benefits, investigation on bioactivity of hot pungent Capsicum sp. products against fungal phytopathogens in vineyards is still scarce. Therefore, the present study aimed at exploring the biologically active compounds profile of a chili pepper (Capsicum chinense Jacq.) pod extract and its antimicrobial properties against some of the major fungal and Oomycetes pathogens of grapevine, including Botrytis cinerea Pers., Guignardia bidwellii (Ellis) Viala & Ravaz and Plasmopara viticola (Berk. & M.A. Curtis) Berl. & De Toni.

RESULTS

The ethyl acetate-extracted oleoresin from the most pungent varieties was rich in capsaicinoids and polyphenols (371.09 and 268.5 μg mg-1 dry weight, respectively). Capsaicin and dihydrocapsaicin, hydroxycinnamic and hydroxybenzoic acids and quercetin derivatives were the most abundant, while carotenoids represented only a minor fraction. The oleoresin was efficient to inhibit all three pathogenic fungi and ED50 values were determined, evidencing that G. bidwellii was the more sensitive (0.233 ± 0.034 mg mL-1 ).

CONCLUSION

The results suggested a potentiality of chili pepper extract for the control of some important grapevine pathogens, their possible application being helpful for the recommended limitation in extensive use of copper in vineyard. The complex mixture of high amounts of capsaicinoids, associated to specific phenolic acids and other minor bioactive components might contribute to the observed antimicrobial action of chili pepper extract. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Calcium Phosphate Particles Coated with Humic Substances: A Potential Plant Biostimulant from Circular Economy

Nowadays, the use of biostimulants to reduce agrochemical input is a major trend in agriculture. In this work, we report on calcium phosphate particles (CaP) recovered from the circular economy, combined with natural humic substances (HSs), to produce a plant biostimulant. CaPs were obtained by the thermal treatment of Salmo salar bones and were subsequently functionalized with HSs by soaking in a HS water solution. The obtained materials were characterized, showing that the functionalization with HS did not sort any effect on the bulk physicochemical properties of CaP, with the exception of the surface charge that was found to get more negative. Finally, the effect of the materials on nutrient uptake and translocation in the early stages of development (up to 20 days) of two model species of interest for horticulture, Valerianella locusta and Diplotaxis tenuifolia, was assessed. Both species exhibited a similar tendency to accumulate Ca and P in hypogeal tissues, but showed different reactions to the treatments in terms of translocation to the leaves. CaP and CaP–HS treatments lead to an increase of P accumulation in the leaves of D. tenuifolia, while the treatment with HS was found to increase only the concentration of Ca in V. locusta leaves. A low biostimulating effect on both plants’ growth was observed, and was mainly scribed to the low concentration of HS in the tested materials. In the end, the obtained material showed promising results in virtue of its potential to elicit phosphorous uptake and foliar translocation by plants.

Plant growth shapes the effects of elevation on the content and variability of flavonoids in subalpine bilberry stands

The study of morphological and physiological responses of shrubs to climate is crucial for the understanding of future scenarios regarding climate change. In this light, studying shrub growth and physiological acclimation along an elevation gradient might be insightful. The phenolic metabolic pathway represents a powerful tool to interpret such processes. In the South-Eastern Alps, we investigated the relationships between elevation, plant traits (i.e. age, xylem ring width, annual shoot length), plant-plant interaction (i.e. shrub cover) and flavonoids in Vaccinium myrtillus L. (leaves, berries) in stands above the treeline. The relationships were parsed within causal networks using a confirmatory path analysis. Elevation was the main driver of V. myrtillus growth, having both direct and indirect effects on the leaf flavonoid content, but this was less evident for berries. In particular, the content of foliar flavonoids showed a peak at mid-elevation and where the growth of xylem rings was intermediate, while it decreased in stands with higher shoot length. Flavonoid content variability of both leaves and berries was affected by elevation and shoot length. In berries, flavonoid variability was further related to all growth traits and shrub cover. These findings evidence that flavonoid content is influenced by both elevation and growth traits of V. myrtillus, often showing non-linear relationships. These results suggest a trait-mediated response of this plant to climate conditions as a result of trade-offs between plant growth, plant defence, environmental stress and nutrient/resource availability.

Analysis of Non-Structural Carbohydrates and Xylem Anatomy of Leaf Petioles Offers New Insights in the Drought Response of Two Grapevine Cultivars

In grapevine, the anatomy of xylem conduits and the non-structural carbohydrates (NSCs) content of the associated living parenchyma are expected to influence water transport under water limitation. In fact, both NSC and xylem features play a role in plant recovery from drought stress. We evaluated these traits in petioles of Cabernet Sauvignon (CS) and Syrah (SY) cultivars during water stress (WS) and recovery. In CS, the stress response was associated to NSC consumption, supporting the hypothesis that starch mobilization is related to an increased supply of maltose and sucrose, putatively involved in drought stress responses at the xylem level. In contrast, in SY, the WS-induced increase in the latter soluble NSCs was maintained even 2 days after re-watering, suggesting a different pattern of utilization of NSC resources. Interestingly, the anatomical analysis revealed that conduits are constitutively wider in SY in well-watered (WW) plants, and that water stress led to the production of narrower conduits only in this cultivar.

Area-based study identifies risk factors associated with missed antenatal corticosteroid prophylaxis in women delivering preterm infants

AIM

All women delivering a preterm infant should receive antenatal corticosteroid prophylaxis, but many miss this opportunity. We determined the risk factors associated with missed prophylaxis in a geographically defined area of Italy.

METHODS

We prospectively studied all mothers who delivered babies between 24 and 31 completed weeks of gestation, from 2009 to 2013, in all maternity units in Tuscany.

RESULTS

Of 1232 mothers, 186 (15.1%) did not receive prophylaxis. The risk was higher in migrant mothers, with an adjusted risk ratio (RR) of 1.28 and 95% confidence interval (95% CI) of 1.04-1.56, and in mothers hospitalised for less than 24 hours (RR 4.09, 95% CI: 2.90-5.78). Preterm prelabour rupture of membranes (RR 0.63, 95% CI: 0.41-0.96) and maternal antepartum transfer (RR 0.24, 95% CI: 0.18-0.32) were protective. Hospital level at birth and gestational age did not influence the prophylaxis rate. The population-attributable fractions were 50.4% for late hospital admissions and 10.2% for migrant status.

CONCLUSION

In a highly organised network of hospitals, neither level of care nor gestational age influenced prophylaxis. Timely arrival of women in hospital, better recognition of the imminence of delivery and tighter steroids administration guidelines are the most relevant targets to further increase prophylaxis.

Neonatal outcome in newborns from mothers with endocrinopathies

INTRODUCTION

Hypothyroidism and gestational diabetes are common endocrine disorders in pregnancy. Our aim is to evaluate the outcome of newborns from mothers with hypothyroidism and from mothers with gestational diabetes.

PATIENTS AND METHODS

The study analysed 216 newborns: 112 from mothers with gestational diabetes and 104 from mothers with hypothyroidism. For each case, we included as a control a newborn of same sex and gestational age from a mother without diabetes or thyreopathy.

RESULTS

In newborns from mothers with gestational diabetes there was an increased frequency of hypoglycaemia and hypocalcaemia, of lower head circumference and of small-for-gestational age (SGA) birth or macrosomy (LGA) than controls. The newborns from mothers with hypothyroidism are more frequently SGA or LGA and they have a slightly increased risk of hypoglycaemia.

CONCLUSIONS

Newborns from mothers with diabetes mellitus or hypothyroidism have an increased risk of being SGA or LGA, and to develop a mild transient hypoglycaemia. Newborns from mothers with diabetes mellitus have also an increased risk to develop hypocalcaemia and to have a lower head circumference than controls. Thus, to prevent SGA or LGA births, it is very important an early diagnosis and treatment, and a strict metabolic control of these conditions.

Increased incidence of esophageal atresia in northwest Tuscany: years 1994-2007

AIM

Esophageal atresia (EA) and imperforate anus are congenital disorders with an incidence that ranges between 1/4000 and 1/5000 births. The aim of this work was to assess the incidence of these malformations in northwest Tuscany and the associated anomalies in comparison with the data published by the Tuscan Congenital Diseases Registry.

METHODS

A retrospective study was made analyzing the cases of these malformations in the years 1994-2007 on a total of 25051 births at the Division of Neonatology of S. Chiara Hospital, Pisa.

RESULTS

The authors found 14 cases of EA and 5 cases of imperforate anus. In these case histories of EA and imperforate anus the incidence was 1/1800 and 1/5000 respectively in comparison with the data issued by the Tuscan Congenital Diseases Registry with an incidence of 1/6644 and 1/1403 in all Tuscany. Five cases of EA (35%) and 2 cases of imperforate anus (40%) were associated with other congenital malformations.

CONCLUSION

Our retrospective study shows a higher incidence of EA in northwest Tuscany than in all the rest of Tuscany unlike the incidence of imperforate anus that it is the same of the rest of Tuscany. In both cases isolated form is most frequent than syndromic one.

Fatal respiratory failure in a full-term newborn with two ABCA3 gene mutations: a case report

Genetic mutations associated with pulmonary surfactant protein deficiency are associated with diverse clinical phenotypes. Mutations of the surfactant protein B and C genes were the first to be described. In 2004, fatal surfactant deficiency in newborns due to mutations of the gene encoding the adenosine triphosphate-binding cassette transporter A3 (ABCA3) was first reported. Few cases of lethal adenosine triphosphate-binding cassette transporter A3 mutations have been described to date. In our report, we describe a full-term newborn that died because of respiratory failure secondary to an uncommon ABCA3 genetic configuration.

Molecular characterization of 6 unrelated Italian patients with 5alpha-reductase type 2 deficiency

Steroid 5alpha-reductase (5alphaR) deficiency (OMIM number #264600) is a rare 46,XY disorder of sex differentiation caused by mutations in the 5alphaR type 2 gene (SRD5A2) resulting in dihydrotestosterone deficiency during fetal development. We report on the analysis of the SRD5A2 gene in 6 unrelated 46,XY Italian patients with external genitalia morphology ranging from predominantly female to nearly completely male. Three subjects were seen and assessed at birth, 1 patient was referred to us before puberty, and 2 at postpubertal age. Six different causative mutations (5 missense and 1 nonsense) and a rare polymorphism were identified. Four patients presented homozygous single-base substitutions. These SRD5A2 mutations were located in exon 2 (variant Cys133Gly), exon 4 (Gly196Ser and Ala207Asp) and exon 5 (Tyr235Phe). A fifth subject was a compound heterozygote who carried a nonsense mutation in exon 1 (Trp53X) and a second SRD5A2 alteration in exon 5 (Tyr235Phe). The final patient presented a mutation in only 1 allele (Gly34Trp) together with the Ala49Thr variant. The molecular characterization of these patients made it possible to identify novel mutations and to confirm, before gender assignment or any surgical approach, the suspected 5alphaR deficiency in 2 newborns, 1 of whom had inconclusive hormonal data. 5alphaR deficiency in subjects without parental consanguinity and the presence of compound heterozygotic patients suggest that SRD5A2 mutations carrier frequency may be higher than previously thought.

Low Birth Weight for Gestational Age Associates with Reduced Glucose Concentrations at Birth, Infancy and Childhood

BACKGROUND/AIMS

Our aim was to investigate glucose homeostasis, insulin sensitivity and insulin-like growth factor (IGF) system status in children born small for gestational age (SGA).

METHODS

A case-control study was carried out at birth, infancy and childhood, comparing SGA with children appropriate for gestational age strictly matched for age, gender, pubertal status and body mass index. Ninety newborns, 52 infants, and 68 children were studied. Fasting insulin (I(F)), fasting glucose (G(F)) to I(F) ratio (G(F)/I(F)), the homeostasis model assessment of insulin sensitivity, the quantitative insulin sensitivity check index, insulinogenic index and the triglyceride/high-density lipoprotein-cholesterol ratio were measured. IGF-I, IGF-binding protein-3 and the IGF-I/IGF-binding protein-3 molar ratio were assessed.

RESULTS

Glucose concentrations were lower in SGA newborns (p < 0.0001), infants (p = 0.01), and children (p = 0.001). Birth weight correlated with glucose levels at birth (r = 0.59, p < 0.0001), 12 months (r = 0.29, p = 0.04) and childhood (r = 0.44, p < 0.0001).

CONCLUSION

Our results provide evidence for a developmental adaptation of glucose metabolism in SGA children leading to reduced glucose concentrations.

Incidence at birth and natural history of cryptorchidism: a study of 10,730 consecutive male infants

Of the 10,730 neonates born in the period 1978-1997 and examined for cryptorchidism (C) at birth, 1387 were pre-term (gestational age <37 wk), and 9343 were full-term. At birth, a total of 737 neonates (6.9%) were cryptorchid, 487 had bilateral C and 250 unilateral C. The C rate of pre-terms was 10 times higher than that of the full-terms (30.1 and 3.4%, respectively). Comparing the two studied decades, a significant decrease of C rate was found in the second decade in full-term neonates. The rates of C at birth were significantly elevated for low birth weight, babies born from mothers with an age <20 or >35 yr, newborns from mothers with A Rh positive and B Rh positive blood group. Of the 737 cryptorchid newborns at birth, 613 (83%) were re-examined after 12 months from the expected date of delivery, and those born in the period 1988-1997 were also re-evaluated at 6 months of life. Late spontaneous descent occurred in 464 cases (75.7%), while 149 (24.3%) were still cryptorchid. The incidence of C at 12 months from the expected date of delivery, after survival curve calculation, in term and pre-term infants, was 1.53 and 7.31%, respectively, in the period 1978-1987, and 1.22 and 3.13% respectively, in the 2nd decade (1988-1997). In the groups also examined at 6 months of life, spontaneous descent occurred almost completely within the first 6 months of life in term infants, but not in pre-terms. No evidence of seasonal cyclicity was found. Medical and/or surgical treatment was generally started within 2-4 yr of age earlier in the second decade of the study. In conclusion, the main risk factor for C at birth and at 12 months of life seems to be pre-term birth and low birth weight. If this is associated itself to a higher risk of infertility too, it remains to be defined.

Adrenarche, pubertal development, age at menarche and final height of full-term, born small for gestational age (SGA) girls

Children born small for gestational age (SGA) may present advanced bone maturation in childhood and reduced final height. The objectives of the study were to evaluate adrenarche, pubertal development, age at menarche and final height in full-term born-SGA girls. Twenty-four girls (12 born-SGA and 12 matched controls) were evaluated at 6-7.5 years of age for clinical signs of puberty and dehydroepiandrosterone sulfate (DHEAS) levels, as a marker of adrenarche. Thirty-eight girls (19 born-SGA and 19 matched controls) were evaluated at 17.5-18.5 years of age to assess final height, sexual maturation and age at menarche. SGA girls had a mean final height (160.1 cm vs 165.8 cm, p < 0.01) and mean weight (52.1 kg vs 56.5 kg, p < 0.05) significantly lower than controls. Controls had a mean final height significantly higher than their mean target height. Sexual maturation was at stage 5 of Tanner's staging in SGA girls and control subjects. SGA girls had a slightly anticipated puberty (9.9 vs 10.4 years for initial breast development) and a lower age at menarche (11.9 vs 12.3 years). At 6-7.5 years of age, SGA females and controls did not show any difference for clinical signs of puberty; however, DHEAS levels (0.75 + 0.18 microgram/ml vs 0.57 + 0.22 microgram/ml, p < 0.05) were significantly higher in SGA girls than in control subjects. We concluded that full-term born-SGA females have impaired final height and weight in adolescence but substantially normal sexual maturation and age at menarche. Increased DHEAS levels before puberty in born-SGA girls may predispose to increased bone maturation in childhood with a reduced final height. In our population a progressive increment in final stature is evident.

Symptomatic hypercalcemia in the first months of life: calcium-regulating hormones and treatment

Neonatal hypercalcemia is a rare condition often of unclear pathogenesis. If unrecognized and untreated it may result in central nervous system and renal damage. We studied three infants with symptomatic neonatal hypercalcemia pointing out pathogenetic and therapeutic aspects. One infant was found to have transient hyperparathyroidism with high intact parathyroid hormone (iPTH) levels. One infant had an incomplete form of Williams syndrome with hypercalcemia and an elfin facies. The pathogenesis is unclear in this case. A reduced secretion of calcitonin or an hypersensitivity to vitamin D might be the underlying defect. The third case was found to have subcutaneous fat necrosis and hypercalcemia associated with high 1,25(OH)2D levels and suppressed iPTH levels. These findings suggest an unregulated extrarenal 1,25(OH)2D production. These infants were treated with hydratation, furosemide, corticosteroids and low calcium diet. Symptomatic neonatal hypercalcemia should be treated promptly. However blood has to be taken before starting treatment to study calcium-regulating hormones and clarify pathogenesis.