The control of crop diseases caused by fungi remains a major problem and there is a need to find effective fungicides that are environmentally friendly. Plants are an excellent source for this ...purpose because they have developed defense mechanisms to cope with fungal infections. Among the plant proteins that play a role in defense are ribosome-inactivating proteins (RIPs), enzymes obtained mainly from angiosperms that, in addition to inactivating ribosomes, have been studied as antiviral, fungicidal, and insecticidal proteins. In this review, we summarize and discuss the potential use of RIPs (and other proteins with similar activity) as antifungal agents, with special emphasis on RIP/fungus specificity, possible mechanisms of antifungal action, and the use of RIP genes to obtain fungus-resistant transgenic plants. It also highlights the fact that these proteins also have antiviral and insecticidal activity, which makes them very versatile tools for crop protection.
We experimentally investigate the extensional flow of a sheet – or curtain – of viscoelastic liquid falling freely from a slot at constant flow rate under gravity. Extruded liquids are aqueous ...solutions of flexible polyethylene oxide (PEO) and of semi-rigid partially hydrolysed polyacrylamide (HPAM) with low shear viscosities. Velocimetry measurements reveal that the mean velocity field
$U(z)$
(where
$z$
is the distance from the slot exit) does not reduce to a free fall. More precisely, we show that the liquid falls initially with sub-gravitational accelerations up to a distance from the slot which scales as
$g\unicodeSTIX{x1D70F}_{fil}^{2}$
(where
$g$
is gravity and
$\unicodeSTIX{x1D70F}_{fil}$
is the extensional relaxation time of the liquid) due to the stretching of polymer molecules. Beyond this elastic length, inertia dominates and the local acceleration reaches the asymptotic free-fall value
$g$
. The length of the sub-gravitational part of the curtain is shown to be much larger than the equivalent viscous length
$((4\unicodeSTIX{x1D702}/\unicodeSTIX{x1D70C})^{2}/g)^{1/3}$
for Newtonian liquids of density
$\unicodeSTIX{x1D70C}$
and dynamic viscosity
$\unicodeSTIX{x1D702}$
which is usually small compared to the curtain length. By analogy with Newtonian curtains, we show that the velocity field
$U(z)$
rescales on a master curve. Besides, the flow is shown to be only weakly affected by the history of polymer deformations in the die upstream of the curtain. Furthermore, investigations on the curtain stability reveal that polymer addition reduces the minimum flow rate required to maintain a continuous sheet of liquid.
Persistent organic pollutants in human milk (HM) at high levels are considered to be detrimental to the breastfed infant. To determine the pesticide concentration in HM, a pilot cross-sectional study ...of 40 Western Australian (WA) women was carried out. Gas chromatography-tandem mass spectrometry (GC-MS/MS) with a validated QuEChERS was used for the analysis of 88 pesticides in HM. p,p′-dichlorodiphenyldichloroethylene (p,p′-DDE) with a mean concentration of 62.8 ± 54.5 ng/g fat was found, whereas other organochlorines, organophosphates, carbamates and pyrethroids were not detected in HM. Overall, no association was observed between HM p,p′-DDE concentrations and maternal age, parity, body mass index and percentage fat mass. Furthermore, for the first time no significant association was found between p,p′-DDE concentrations in HM and infant growth outcomes such as weight, length, head circumference and percentage fat mass. The calculated daily intake was significantly different to the estimated daily intake of total DDTs and was well below the guideline proposed by WHO. The DDTs levels in WA have also significantly decreased by 42 - fold since the 1970s and are currently the lowest in Australia.
•Cross-sectional study of 88 POPs in human milk over first year of lactation.•p,p′-DDE was detected in 87.5% of the human milk samples.•No significant associations between p,p′-DDE and infant growth outcomes.•Estimated daily intake overestimates human milk POP concentration.•Human milk infant intake of DDTs is below the recommended daily intake guidelines.
Human milk (HM) lipid content is highly variable, and infants consume different volumes of milk. This makes precise sampling and calculation of the infant lipid intake problematic.
In order to ...describe inaccuracies of estimates of lipid content introduced by various sampling protocols, we compared the true infant lipid intake with estimated intakes using different milk sampling protocols.
Monthly milk samples (n = 1026) from months 1 to 6 of lactation were collected from 20 healthy, exclusively breastfeeding women. Infant lipid intake was measured by 24-hour test-weighing at month 3. Total lipid content was measured by creamatocrit. Concentrations and infant lipid intakes were calculated using 11 sampling protocols, using either the true milk intake or an average of 800 mL/d. These estimates were compared with the true infant lipid intake using repeated-measures ANOVA and linear mixed modeling with multiple comparisons.
The mean maternal age was 32.0 years (SD ± 3.10), and infants were born term (40.1 ± 1.1 weeks) with a mean birth weight of 3.87 kg (SD ± 0.39). The mean true infant lipid intake was 28.6 g/d (SD ± 9.8). The mean estimated lipid intake using 1 morning pre-feed sample underestimated intake by >8.0 g/d. Estimates of infant lipid intake using other sampling protocols and an assumed intake volume of 800 mL/d also resulted in a wide range of differences (0.8–18.1 g/d) from the true intake. Use of 6 daily pre- and post-feed milk samples had a mean difference of only 0.1 g/d (95% CI, –2.9 to 2.7) from the true intake.
A sampling protocol with 6 pre- and post-feed samples provides the most accurate estimate of lipid intake if it is not possible to perform 24-hour test weights. The potential inaccuracies of sampling protocols should be taken into consideration in the interpretation and translation of infant lipid intake results.
Human milk contains a complex combination of lipids, proteins, carbohydrates, and minerals, which are essential for infant growth and development. While the lipid portion constitutes only 5% of the ...total human milk composition, it accounts for over 50% of the infant's daily energy intake. Human milk lipids vary throughout a feed, day, and through different stages of lactation, resulting in difficulties in sampling standardization and, like blood, human milk is bioactive containing endogenous lipases, therefore appropriate storage is critical in order to prevent lipolysis. Suitable sample preparation, often not described in studies, must also be chosen to achieve the aims of the study. Gas chromatography methods have classically been carried out to investigate the fatty acid composition of human milk lipids, but with the advancement of other chromatographic techniques, such as liquid and supercritical fluid chromatography, as well as mass spectrometry, intact lipids can also be characterized. Despite the known importance, concise and comprehensive analysis of the human milk lipidome is limited, with gaps existing in all areas of human milk lipidomics, discussed in this review. With appropriate methodology and instrumentation, further understanding of the human milk lipidome and the influence it has on infant outcomes can be achieved.
•We estimate the public’s willingness to pay (WTP) for a theoretical bee protection policy in the UK.•The mean WTP to support the bee protection policy was approximately £43 per household per ...year.•The total value of public support obtained through the CV method is substantial, estimated to be £842 million per year.•This value can provide a means of illustrating the total value of public support for maintaining pollination services.
There is concern that insect pollinators, such as bees, are currently declining in abundance, and are under serious threat from factors such as increased use of certain pesticides, land use changes, competition from invasive alien species, pathogens, parasites and climate change. Using the contingent valuation (CV) method, this paper evaluates how much public support there would be in preventing further decline to maintain the current number of bees by estimating the willingness to pay (WTP) for a theoretical bee protection policy in the UK. We apply the CV method as an estimation of public perception and preferences for pollination services. The mean WTP to support the bee protection policy was approximately £43 per household per year. Based on the 30.6 million taxpayers in the UK, this is equivalent to £842 million per year. This value can provide a means of illustrating the total value of public support for maintaining pollination services to policy makers and stakeholders.
The ATPase Family, AAA domain-containing protein 2 (ATAD2) bromodomain (BRD) has a canonical bromodomain structure consisting of four α-helices. ATAD2 functions as a co-activator of the androgen and ...estrogen receptors as well as the MYC and E2F transcription factors. ATAD2 also functions during DNA replication, recognizing newly synthesized histones. In addition, ATAD2 is shown to be up-regulated in multiple forms of cancer including breast, lung, gastric, endometrial, renal, and prostate. Furthermore, up-regulation of ATAD2 is strongly correlated with poor prognosis in many types of cancer, making the ATAD2 bromodomain an innovative target for cancer therapeutics. In this study, we describe the recognition of histone acetyllysine modifications by the ATAD2 bromodomain. Residue-specific information on the complex formed between the histone tail and the ATAD2 bromodomain, obtained through nuclear magnetic resonance spectroscopy (NMR) and X-ray crystallography, illustrates key residues lining the binding pocket, which are involved in coordination of di-acetylated histone tails. Analytical ultracentrifugation, NMR relaxation data, and isothermal titration calorimetry further confirm the monomeric state of the functionally active ATAD2 bromodomain in complex with di-acetylated histone ligands. Overall, we describe histone tail recognition by ATAD2 BRD and illustrate that one acetyllysine group is primarily engaged by the conserved asparagine (N1064), the "RVF" shelf residues, and the flexible ZA loop. Coordination of a second acetyllysine group also occurs within the same binding pocket but is essentially governed by unique hydrophobic and electrostatic interactions making the di-acetyllysine histone coordination more specific than previously presumed.
The fatty acids (FAs) of human milk (HM) are the building blocks of the HM lipidome, contributing to infant health and development; however, this has not been comprehensively characterised with ...respect to infant intake. Eighteen Western Australian mother–infant dyads provided monthly longitudinal HM samples during six months of exclusive breastfeeding. Monthly anthropometric measurements, health data and basic maternal food frequency data were also collected. At three months, infant 24 h milk intake and total lipid intake were measured. The FA profile was analysed using gas chromatography–mass spectrometry. Linear regression and Pearson’s correlation were used to identify associations between HM FA composition, HM FA intake, maternal characteristics and infant growth and developmental outcomes. Mean infant intake of total lipids was 29.7 ± 9.4 g/day. HM FA composition exhibited wide variation between dyads and throughout lactation. Infant intake of a number of FAs, including C15:0, C18:1, C18:2 and C20:3, was positively related to infant growth (all p < 0.001). There were no relationships detected between C22:5 and C20:5 and infant head circumference. Infant total lipid intake and the infant intake of many FAs play essential roles in infant growth and development. This study highlights the important relationships of many HM FAs not previously described, including C15:0 and C18:2 species. Infant outcomes should be considered in the context of intake in future HM studies.
Le syndrome GACI ou calcifications artérielles généralisées de l’enfance est une maladie autosomique récessive rare caractérisée par des calcifications artérielles et péri-articulaires. La plupart ...des enfants décèdent dans les premiers mois de vie de complications cardiovasculaires. Un rachitisme hypophosphatémique (RH) résistant au traitement médical peut compléter le phénotype, le pronostic vital est alors meilleur. Nous décrivons l’observation d’une fillette qui présentait des calcifications périarticulaires néonatales ectopiques, de régression spontanée, puis à l’âge de 3ans un RH et une surdité par ankylose stapédo-vestibulaire. La supplémentation phospho-vitaminique n’a permis aucune amélioration clinique et la correction des phosphatases alcalines s’est compliquée d’une récidive tissulaire et vasculaire des calcifications : la supplémentation a été diminuée et les déformations osseuses corrigées chirurgicalement. Le diagnostic de GACI a été confirmé par séquençage du gène ENPP1 (ecto-nucléotide pyrophosphatase/phosphodiesterase 1). Des anomalies rétiniennes et une diminution des pouls périphériques sont venues compléter le phénotype vers l’âge de 4ans et demi, ces signes sont habituellement observés dans le pseudo-xanthome élastique (PXE). GACI et PXE sont considérés aujourd’hui comme deux entités d’un même spectre, caractérisées par des calcifications viscérales et artérielles diffuses. Cette observation en est une illustration.
GACI (generalized arterial calcification of infancy) is a rare autosomal recessive disorder characterized by arterial and periarticular calcifications. Most children die in the first months of life of cardiovascular complications. Hypophosphatemic rickets (HR) resistant to medical treatment may complete the phenotype and is associated with a milder phenotype. This report discusses the case of a girl who presented neonatal ectopic periarticular calcifications with spontaneous regression, and then at the age of 3years developed HR. There was no clinical improvement after treatment with calcitriol and phosphate, and correction of alkaline phosphatase induced the recurrence of periarticular and tissular calcifications : the treatment was reduced and the bone distortion treated by surgery. GACI diagnosis was confirmed by genetic analysis. At the age of 4.5years, she developed a retinal abnormality and decreased radial pulse: these clinical signs are usually observed in pseudoxanthoma elasticum (PXE). It is now established that GACI and PXE belong to the same entity characterized by arterial and tissular calcifications of which this original case report is an illustration.
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