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Cardiovascular diseases remain a leading cause of mortality globally, with atherosclerosis representing a significant pathological means, often leading to myocardial infarction. Coronary artery bypass surgery, a common procedure used to treat coronary artery disease, presents challenges due to the limited autologous tissue availability or the shortcomings of synthetic grafts. Consequently, there is a growing interest in tissue engineering approaches to develop vascular substitutes. This review offers an updated picture of the state of the art in vascular tissue engineering, emphasising the design of scaffolds and dynamic culture conditions following a biomimetic approach. By emulating native vessel properties and, in particular, by mimicking the three-layer structure of the vascular wall, tissue-engineered grafts can improve long-term patency and clinical outcomes. Furthermore, ongoing research focuses on enhancing biomimicry through innovative scaffold materials, surface functionalisation strategies, and the use of bioreactors mimicking the physiological microenvironment. Through a multidisciplinary lens, this review provides insight into the latest advancements and future directions of vascular tissue engineering, with particular reference to employing biomimicry to create systems capable of reproducing the structure-function relationships present in the arterial wall. Despite the existence of a gap between benchtop innovation and clinical translation, it appears that the biomimetic technologies developed to date demonstrate promising results in preventing vascular occlusion due to blood clotting under laboratory conditions and in preclinical studies. Therefore, a multifaceted biomimetic approach could represent a winning strategy to ensure the translation of vascular tissue engineering into clinical practice.

Background: Abdominal hernia repair surgeries involve the fixation of a surgical mesh to the abdominal wall with different means such as suture, tacks, and glues. Currently, the most effective mesh fixation system is still debated. This review compares outcomes of mesh fixation in different surgical procedures, aiding surgeons in identifying the optimal technique., Methods: A meta-analysis was conducted according to PRISMA guidelines. Articles published between January 2003 and January 2023 were searched in electronic databases. Randomized controlled trials (RCTs) comparing mesh fixation with cyanoacrylate-based or fibrin glues with classical fixation techniques (sutures, tacks) in open and laparoscopic procedures were included., Results: 17 RCTs were identified; the cumulative study population included 3919 patients and a total of 3976 inguinal hernias. Cyanoacrylate-based and fibrin glues were used in 1639 different defects, suture and tacks in 1912 defects, self-gripping mesh in 404 cases, and no mesh fixation in 21 defects. Glue fixation resulted in lower early postoperative pain, and chronic pain occurred less frequently. The incidence of hematoma was lower with glue fixation than with mechanical fixation. Recurrence rate, seroma formation, operative and hospitalization time showed no significant differences; but significantly, a higher number of people in the glue group returned to work by 15- and 30-days after surgery when compared to the tacker and suture groups in the same time frame., Conclusion: Cyanoacrylate and fibrin glue may be effective in reducing early and chronic pain and hematoma incidence without increasing the recurrence rate, the seroma formation, or the operative and hospitalization time., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Since 2015, an unprecedented number of people from Middle Eastern and African countries have crossed borders into and within Europe. Media and political actors describe this time as an "emergency" and a "crisis" that challenges the core of European values and human rights principles. Calling this a crisis implies responding to it, on the one hand, with humanitarian gestures of saving lives, and, on the other, with stricter border control. I reflect on the grammar of crisis and the forms of care that it simultaneously enables and disables. I am inspired by the relationship between two painters-from Tunisia and Nigeria-and their forms of therapeutic and ethical explorations through art. I propose to attend to practices that bear witness to other grammars, or the lack thereof. These practices are the expression of a denial, or, better, of an interruption in the language of the crisis and pathology., (© 2020 by the American Anthropological Association.)

The potential of Arundo donax to grow in degraded soils, characterized by excess of salinity (Na+), and phosphorus deficiency (-P) or excess (+P) also coupled with salinity (+NaP), was investigated by combining in vivo plant phenotyping, quantification of metabolites and ultrastructural imaging of leaves with a transcriptome-wide screening. Photosynthesis and growth were impaired by + Na, -P and + NaP. While + Na caused stomatal closure, enhanced biosynthesis of carotenoids, sucrose and isoprene and impaired anatomy of cell walls, +P negatively affected starch production and isoprene emission, and damaged chloroplasts. Finally, +NaP largely inhibited photosynthesis due to stomatal limitations, increased sugar content, induced/repressed a number of genes 10 time higher with respect to + P and + Na, and caused appearance of numerous and large plastoglobules and starch granules in chloroplasts. Our results show that A. donax is sensitive to unbalances of soil ion content, despite activation of defensive mechanisms that enhance plant resilience, growth and biomass production of A. donax under these conditions., (Copyright © 2019. Published by Elsevier B.V.)

Anthocyanic morphs are generally less efficient in terms of carbon gain, but, in turn, are more photoprotected than anthocyanin-less ones. To date, mature leaves of different morphs or leaves at different developmental stages within the same species have generally been compared, whereas there is a lack of knowledge regarding different stages of development of red vs . green leaves. Leaves (1-, 7-, and 13-week-old) of red- (RLP) and green-leafed (GLP) Prunus in terms of photosynthetic rate, carbon metabolism and photoprotective mechanisms were compared to test whether anthocyanin-equipped leaves perform better than anthocyanin-less leaves and whether photoprotection is the primary role of epidermally-located anthocyanins, using for the first time a recently-developed parameter of chlorophyll fluorescence (qPd). GLP leaves had a higher photosynthetic rate in 1- and 7-week-old leaves, but RLP leaves performed better at an early stage of senescence and had a longer leaf lifespan. Anthocyanins contributed to leaf photoprotection throughout the leaf development, but were tightly coordinated with carotenoids. Besides photoprotecting, we propose that epidermal anthocyanins may be principally synthetized to maintain an efficient carbon-sink strength in young and senescent leaves, thus extending the RLP leaf lifespan.

In 1978, Italy passed a law establishing the abolition of the mental hospital. Up to that time, the traditional asylums were still governed by the 1904 law that positioned psychiatry within the criminal justice system by assigning it the function of custodia (control, custody) rather than of cura (care). In the 1960s and 1970s, Italian psychiatrist Franco Basaglia initiated a movement of de-institutionalization of the mentally ill that revolutionized psychiatric care in Italy. It also had a deep impact on restructuring the psychiatric system in other European and Latin American countries. In this article, I discuss the different psychiatric practices and imaginaries that resulted from the movement of democratic psychiatry and Basaglia's visions for a community-based and diagnosis-free care of the mentally ill. I ethnographically trace what I call the "Basaglia effect" in today's psychiatric practices, and focus on ethnopsychiatry as a counter clinic that emerged from Basaglia's legacy. I reflect on the frictions between care and cure that ethnopsychiatry re-articulates and works with in the context of contemporary migrations to Europe.

Saline soils are highly heterogeneous in time and space, and this is a critical factor influencing plant physiology and productivity. Temporal changes in soil salinity can alter plant responses to salinity, and pre-treating plants with low NaCl concentrations has been found to substantially increase salt tolerance in different species in a process called acclimation. However, it still remains unclear whether this process is common to all plants or is only expressed in certain genotypes. We addressed this question by assessing the physiological changes to 100 mM NaCl in two contrasting olive cultivars (the salt-sensitive Leccino and the salt-tolerant Frantoio), following a 1-month acclimation period with 5 or 25 mM NaCl. The acclimation improved salt tolerance in both cultivars, but activated substantially different physiological adjustments in the tolerant and the sensitive cultivars. In the tolerant Frantoio the acclimation with 5 mM NaCl was more effective in increasing plant salt tolerance, with a 47% increase in total plant dry mass compared with non-acclimated saline plants. This enhanced biomass accumulation was associated with a 50% increase in K+ retention ability in roots. On the other hand, in the sensitive Leccino, although the acclimation process did not improve performance in terms of plant growth, pre-treatment with 5 and 25 mM NaCl substantially decreased salt-induced leaf cell ultrastructural changes, with leaf cell relatively similar to those of control plants. Taken together these results suggest that in the tolerant cultivar the acclimation took place primarily in the root tissues, while in the sensitive they occurred mainly at the shoot level., (© The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Superparamagnetic iron oxide nanoparticles (SPIONs) have received increasing interest as contrast media in biomedical imaging and innovative therapeutic tools, in particular for loco-regional ablative treatments and drug delivery. The future of therapeutic applications would strongly benefit from improving the capability of the nanostructured constructs to reach the selected target, in particular beyond the intravascular space. Besides the decoration of SPIONs surface with ad hoc bioactive molecules, external magnetic fields are in principle able to remotely influence SPIONs' physiological biodistribution and concentrate them to a specific anatomical region or portion of a tissue. The reduction of SPIONs administered to the body and the need for defining the effective SPIONs local concentration suggest that PET/CT may be a method to quantitatively detect the nanoparticles accumulation in vivo at low concentration and assess their tridimensional distribution in response to an external magnetic field and in relation to the local anatomy highlighted by CT imaging. Here, we report on the possibility to assess the spatial distribution of magnetically-driven radiolabelled SPIONs in a peripheral tissue (mouse thigh) with microPET/CT imaging. To this aim we labelled SPIONs using 18 F-2-fluoro-2-deoxyglucose as a synthon, by chemoselective oxime formation between its open-chain tautomer and nanoparticle amino-groups, and employed microPET/CT imaging to measure the radiolabelled construct biodistribution in a small animal model, following intravenous administration, with and without the application of a permanent magnet onto the skin. The in vivo and ex vivo results showed that micro-PET/CT was able to demonstrate the localizing action of the magnet on SPIONs and provide information, in a multimodal 3D data set, about SPIONs biodistribution taking into account the local anatomy. Copyright © 2017 John Wiley & Sons, Ltd., (Copyright © 2017 John Wiley & Sons, Ltd.)

In this article, I analyze the practices of a group of Catholic nuns who run shelters for 'victims of human trafficking' in Italy, and are thus involved in state-funded rehabilitation programs for former foreign prostitutes. This case shows how the state and the Church are deeply implicated in each other's projects of redemption and the creation of new forms of life. In Italy, the legal model for rehabilitating foreign prostitutes is avowedly secular yet also deeply shaped by a Catholic impetus to purify sinners. At the same time, however, the nuns themselves develop an understanding of redemption as a secular life-saving project in line with the state's project of recognition, and thus inscribe their practices within the biopolitical effort to transform lives. Ultimately, I argue, leading by example becomes a specific Catholic instantiation of biopolitics that characterizes both the state's and the Church's approach to foreigners.

The ability to modify mesophyll conductance (gm ) in response to changes in irradiance may be a component of the acclimation of plants to shade-sun transitions, thus influencing species-specific distributions along light-gradients, and the ecological niches for the different species. To test this hypothesis we grew three woody species of the Oleaceae family, the evergreen Phillyrea latifolia (sun-requiring), the deciduous Fraxinus ornus (facultative sun-requiring) and the hemi-deciduous Ligustrum vulgare (shade tolerant) at 30 or 100% sunlight irradiance. We show that neither mesophyll conductance calculated with combined gas exchange and chlorophyll fluorescence techniques (gm) nor CO2 assimilation significantly varied in F. ornus because of sunlight irradiance. This corroborates previous suggestions that species with high plasticity for light requirements, do not need to undertake extensive reorganization of leaf conductances to CO2 diffusion to adapt to different light environments. On the other hand, gm steeply declined in L. vulgare and increased in P. latifolia exposed to full-sun conditions. In these two species, leaf anatomical traits are in part responsible for light-driven changes in gm , as revealed by the correlation between gm and mesophyll conductance estimated by anatomical parameters (gmA). Nonetheless, gm was greatly overestimated by gmA when leaf metabolism was impaired because of severe light stress. We show that gm is maximum at the light intensity at which plant species have evolved and we conclude that gm actually plays a key role in the sun and shade adaptation of Mediterranean species. The limits of gmA in predicting mesophyll conductance are also highlighted., (© 2015 Scandinavian Plant Physiology Society.)

Engineered nanoscale materials (ENMs) are considered emerging contaminants since they are perceived as a potential threat to the environment and the human health. The reactions of living organisms when exposed to metal nanoparticles (NPs) or NPs of different size are not well known. Very few studies on NPs-plant interactions have been published, so far. For this reason there is also great concern regarding the potential NPs impact to food safety. Early genotoxic and phytotoxic effects of cerium oxide NPs (nCeO2) and titanium dioxide NPs (nTiO2) were investigated in seedlings of Hordeum vulgare L. Caryopses were exposed to an aqueous dispersion of nCeO2 and nTiO2 at, respectively 0, 500, 1000, and 2000 mg l(-1) for 7 days. Genotoxicity was studied by Randomly Amplified Polymorphism DNA (RAPDs) and mitotic index on root tip cells. Differences between treated and control plants were observed in RAPD banding patterns as well as at the chromosomal level with a reduction of cell divisions. At cellular level we monitored the oxidative stress of treated plants in terms of reactive oxygen species (ROS) generation and ATP content. Again nCeO2 influenced clearly these two physiological parameters, while nTiO2 were ineffective. In particular, the dose 500 mg l(-1) showed the highest increase regarding both ROS generation and ATP content; the phenomenon were detectable, at different extent, both at root and shoot level. Total Ce and Ti concentration in seedlings was detected by ICP-OES. TEM EDSX microanalysis demonstrated the presence of aggregates of nCeO2 and nTiO2 within root cells of barley. nCeO2 induced modifications in the chromatin aggregation mode in the nuclei of both root and shoot cells.

The presence of Psidium guajava in polluted environments has been reported in recent studies, suggesting that this species has a high tolerance to the metal stress. The present study aims at a physiological characterization of P. guajava response to high nickel (Ni) concentrations in the root-zone. Three hydroponic experiments were carried out to characterize the effects of toxic Ni concentrations on morphological and physiological parameters of P. guajava, focusing on Ni-induced damages at the root-level and root ion fluxes. With up to 300μM NiSO4 in the root-zone, plant growth was similar to that in control plants, whereas at concentrations higher than 1000μM NiSO4 there was a progressive decline in plant growth and leaf gas exchange parameters; this occurred despite, at all considered concentrations, plants limited Ni(2+) translocation to the shoot, therefore avoiding shoot Ni(2+) toxicity symptoms. Maintenance of plant growth with 300μM Ni(2+) was associated with the ability to retain K(+) in the roots meanwhile 1000 and 3000μM NiSO4 led to substantial K(+) losses. In this study, root responses mirror all plant performances suggesting a direct link between root functionality and Ni(2+) tolerance mechanisms and plant survival. Considering that Ni was mainly accumulated in the root system, the potential use of P. guajava for Ni(2+) phytoextraction in metal-polluted soils is limited; nevertheless, the observed physiological changes indicate a good Ni(2+) tolerance up to 300μM NiSO4 suggesting a potential role for the phytostabilization of polluted soils., (Copyright © 2014 Elsevier GmbH. All rights reserved.)

The location of individual coumarins in leaves of Fraxinus ornus acclimated at full solar irradiance was estimated using their specific UV- and fluorescence spectral features. Using a combination of UV-induced fluorescence and blue light-induced fluorescence of tissues stained with diphenylborinic acid 2-amino-ethylester, in wide field or confocal laser scanning microscopy, we were able to visualize the distribution of esculetin and esculetin 6-O-glucoside (esculin) in palisade cells. Coumarins are not uniformly distributed in the cell vacuole, but accumulate mostly in the adaxial portion of palisade cells. Our study indeed shows, for the first time, that coumarins in palisade cells accumulate as vacuolar inclusions, as previously reported in the pertinent literature only for anthocyanins. Furthermore, esculetin and esculin have a different vacuolar distribution: esculetin largely predominates in the first 15 μm from the adaxial epidermis. This leads to hypothesize for esculetin and esculin different transport mechanisms from the endoplasmic reticulum to the vacuole as well as potentially different roles in photoprotection. Our study open to new experiments aimed at exploring the mechanisms that deliver coumarins to the vacuole using different fluorescence signatures of coumarin aglycones and coumarin glycosides., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The putative photoprotective role of foliar anthocyanins continues to attract heated debate. Strikingly different experimental set-ups coupled with a poor knowledge of anthocyanin identity have likely contributed to such disparate opinions. Here, the photosynthetic responses to 30 or 100% solar irradiance were compared in two cultivars of basil, the green-leafed Tigullio (TG) and the purple-leafed Red Rubin (RR). Coumaroyl anthocyanins in RR leaf epidermis significantly mitigated the effects of high light stress. In full sunlight, RR leaves displayed several shade-plant traits; they transferred less energy than did TG to photosystem II (PSII), and non-photochemical quenching was lower. The higher xanthophyll cycle activity in TG was insufficient to prevent inactivation of PSII in full sunlight. However, TG was the more efficient in the shade; RR was far less able to accommodate a large change in irradiance. Investment of carbon to phenylpropanoid biosynthesis was more in RR than in TG in the shade, and was either greatly enhanced in TG or varied little in RR because of high sunlight. The metabolic cost of photoprotection was lower whereas light-induced increase in biomass production was higher in RR than in TG, thus making purple basil the more light tolerant. Purple basil appears indeed to display the conservative resource-use strategy usually observed in highly stress tolerant species. We conclude that the presence of epidermal coumaroyl anthocyanins confers protective benefits under high light, but it is associated with a reduced plasticity to accommodate changing light fluxes as compared with green leaves., (© 2014 Scandinavian Plant Physiology Society.)

Background and Aims: A major challenge in plant ecophysiology is understanding the effects of multiple sub-optimal environmental conditions on plant performance. In most Mediterranean areas soil salinity builds up during the summer because of low availability of soil water coupled with hot temperatures. Although sunlight and soil salinity may strongly interact in determining a plant's performance, this has received relatively little attention., Methods: Two-year-old seedlings of Fraxinus ornus were grown outdoors in pots during a Mediterranean summer in either 45 % (shaded plants) or 100 % (sun plants) sunlight irradiance and were supplied with either deionized water or deionized water plus 75 mm NaCl. Morpho-anatomical traits, water and ionic relations, gas exchange and photosystem II performance, concentrations of individual carotenoids, activity of antioxidant enzymes, concentrations of ascorbic acid and individual polyphenols were measured in leaves. Leaf oxidative stress and damage were estimated by in vivo analysis of stable free radicals and ultrastructural analyses., Key Results: Leaf concentrations of potentially toxic ions did not markedly differ in shaded or sun plants in response to salinity. Leaves of sun plants displayed superior water use efficiency compared with leaves of shaded plants, irrespective of salinity treatment, and had both better stomatal control and higher CO2 carboxylation efficiency than leaves of shaded plants. In the salt-treated groups, the adverse effects of excess midday irradiance were greater in shade than in sun plants. The activity of enzymes responsible for detoxifying hydrogen peroxide decreased in shaded plants and increased in sun plants as a result of salinity stress. In contrast, the activity of guaiacol peroxidase and the concentration of phenylpropanoids increased steeply in response to salinity in shaded plants but were unaffected in sun plants., Conclusions: It is concluded that salinity may constrain the performance of plants growing under partial shading more severely than that of plants growing under full sun during summer. The results suggest co-ordination within the antioxidant defence network aimed at detoxifying salt-induced generation of reactive oxygen species., (© The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Evidence suggests that heavy-metal tolerance can be induced in plants following pre-treatment with non-toxic metal concentrations, but the results are still controversial. In the present study, tobacco plants were exposed to increasing Zn2+ concentrations (up to 250 and/or 500 μM ZnSO4) with or without a 1-week acclimation period with 30 μM ZnSO4. Elevated Zn2+ was highly toxic for plants, and after 3 weeks of treatments there was a marked (≥50%) decline in plant growth in non-acclimated plants. Plant acclimation, on the other hand, increased plant dry mass and leaf area up to 1.6-fold compared with non-acclimated ones. In non-acclimated plants, the addition of 250 μM ZnSO4 led to transient membrane depolarization and stomatal closure within 24h from the addition of the stress; by contrast, the acclimation process was associated with an improved stomatal regulation and a superior ability to maintain a negative root membrane potential, with values on average 37% more negative compared with non-acclimated plants. The different response at the plasma-membrane level between acclimated and non-acclimated plants was associated with an enhanced vacuolar Zn2+ sequestration and up to 2-fold higher expression of the tobacco orthologue of the Arabidopsis thaliana MTP1 gene. Thus, the acclimation process elicited specific detoxification mechanisms in roots that enhanced Zn2+ compartmentalization in vacuoles, thereby improving root membrane functionality and stomatal regulation in leaves following elevated Zn2+ stress., (© The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.)

For thousands of years, olive trees (Olea europaea L.) have been a significant presence and a symbol in the Garden of Gethsemane, a place located at the foot of the Mount of Olives, Jerusalem, remembered for the agony of Jesus Christ before his arrest. This investigation comprises the first morphological and genetic characterization of eight olive trees in the Garden of Gethsemane. Pomological traits, morphometric, and ultrastructural observations as well as SSR (Simple Sequence Repeat) analysis were performed to identify the olive trees. Statistical analyses were conducted to evaluate their morphological variability. The study revealed a low morphological variability and minimal dissimilarity among the olive trees. According to molecular analysis, these trees showed the same allelic profile at all microsatellite loci analyzed. Combining the results of the different analyses carried out in the frame of the present work, we could conclude that the eight olive trees of the Gethsemane Garden have been propagated from a single genotype., (Copyright © 2014. Published by Elsevier SAS.)

Metallic nanoparticles (MeNPs) can be formed in living plants by reduction of the metal ions absorbed as soluble salts. It is very likely that plant metabolism has an important role in MeNP biosynthesis. The in vivo formation of silver nanoparticles (AgNPs) was observed in Brassica juncea, Festuca rubra and Medicago sativa. Plants were grown in Hoagland's solution for 30 days and then exposed for 24 h to a solution of 1,000 ppm AgNO3. In the leaf extracts of control plants, the concentrations of glucose, fructose, ascorbic acid, citric acid and total polyphenols were determined. Total Ag content in plant fractions was determined by inductively coupled plasma atomic emission spectroscopy. Despite the short exposure time, the Ag uptake and translocation to plant leaves was very high, reaching 6,156 and 2,459 mg kg-1 in B. juncea and F. rubra, respectively. Ultrastructural analysis was performed by transmission electron microscopy (TEM), and AgNPs were detected by TEM X-ray microanalysis. TEM images of plant fractions showed the in vivo formation of AgNPs in the roots, stems and leaves of the plants. In the roots, AgNPs were present in the cortical parenchymal cells, on the cell wall of the xylem vessels and in regions corresponding to the pits. In leaf tissues, AgNPs of different sizes and shapes were located close to the cell wall, as well as in the cytoplasm and within chloroplasts. AgNPs were not observed in the phloem of the three plant species. This is the first report of AgNP synthesis in living plants of F. rubra. The contents of reducing sugars and antioxidant compounds, proposed as being involved in the biosynthesis of AgNPs, were quite different between the species, thus suggesting that it is unlikely that a single substance is responsible for this process. MSC 2010: 92 Biology and other natural sciences; 92Cxx Physiological, cellular and medical topics; 92C80 Plant biology.

Combustion processes commonly create fine and ultrafine particles whose effects are often harmful to human health. The present study is aimed at providing more data in this field by testing the capability of environmental electron scanning microscopy of detecting and analyzing such particles. For this purpose, we examined a range of samples taken from everyday food items collected in Tuscany. The results showed that, within the examined samples, inorganic particles can be observed in the nano- and micrometer range. These particles are attributable mostly to natural processes and, in part, to food processing. Little evidence is found for particles whose origin could be attributed to industrial combustion processes, such as waste incineration., (Copyright © 2011 Wiley-Liss, Inc.)

Based on two years of ethnographic fieldwork at the Centro Frantz Fanon, an ethnopsychiatric clinic in Northern Italy, this article traces the theoretical and clinical genealogy of Italian ethnopsychiatry as it is conceived and practiced at this clinic. The clinic draws explicitly from the work of Fanon and French ethnopsychologist Tobie Nathan. This genealogy provides a basis for reflection on the ways in which current ethnopsychiatry re-articulates older questions about difference and healing, culture and suffering, and the political dimensions of psychiatry. Although ethnopsychiatry is currently focused on the care of migrants, key issues related to the impact of colonialism on mental illness and the recognition of cultural difference characterized the Italian debate long before the 1980s when increasing numbers of migrants and political refugees started to arrive in Italy.

Two bean cultivars with different sensitivity to ozone, i.e. the O3-sensitive Cannellino and the O3-tolerant Top Crop, were exposed to acute O3-stress (165 nL L(-1)) with the aim of evaluating physiological and biochemical traits that may confer O3-tolerance. Stomatal conductance was smaller and the ability to dissipate excess energy, via regulated and unregulated nonphotochemical quenching mechanisms was greater in Top Crop than in Cannellino. These morphological and physiological-traits allowed the O3-tolerant cultivar to compensate for the light-induced declines in PhiPSII, to preserve photosystem II from excitation-energy, and likely to prevent the generation of ROS to a superior degree than the O3-sensitive cultivar. Furthermore, the potential capacities to reducing the superoxide anion and H2O2 were significantly greater in Top Crop than in Cannellino. These findings are consistent with the early accumulation of H2O2, the almost complete disruption of cell structure, and irreversible damages to the photosynthetic apparatus observed in the O3-sensitive cultivar., (Copyright (c) 2010 Elsevier Ltd. All rights reserved.)

The role of flavonoids in mechanisms of acclimation to high solar radiation was analysed in Ligustrum vulgare and Phillyrea latifolia, two Mediterranean shrubs that have the same flavonoid composition but differ strikingly in their leaf morpho-anatomical traits. In plants exposed to 12 or 100% solar radiation, measurements were made for surface morphology and leaf anatomy; optical properties, photosynthetic pigments, and photosystem II efficiency; antioxidant enzymes, lipid peroxidation and phenylalanine ammonia lyase; synthesis of hydroxycinnamates and flavonoids; and the tissue-specific distribution of flavonoid aglycones and ortho-dihydroxylated B-ring flavonoid glycosides. A denser indumentum of glandular trichomes, coupled with both a thicker cuticle and a larger amount of cuticular flavonoids, allowed P. latifolia to prevent highly damaging solar wavelengths from reaching sensitive targets to a greater degree than L. vulgare. Antioxidant enzymes in P. latifolia were also more effective in countering light-induced oxidative load than those in L. vulgare. Consistently, light-induced accumulation of flavonoids in L. vulgare, particularly ortho-dihydroxylated flavonoids in the leaf mesophyll, greatly exceeded that in P. latifolia. We conclude that the accumulation of flavonoid glycosides associated with high solar radiation-induced oxidative stress and, hence, biosynthesis of flavonoids appear to be unrelated to 'tolerance' to high solar radiation in the species examined., (Copyright New Phytologist (2005).)