Assisted reproductive technology, risk of gestational diabetes, and perinatal outcomes in singleton pregnancies.

AIMS: To evaluate the impact of assisted reproductive technology (ART) on the risk of gestational diabetes mellitus (GDM) in single pregnancies. MATERIALS AND METHODS: We retrospectively collected clinical and anthropometric data of 219ART- and 256 age- and body mass index (BMI)-matched women with spontaneous conception screened for GDM. The primary outcome was to evaluate GDM prevalence in ART women. RESULTS: There were no differences in age, BMI, and family history of diabetes in the two groups of women. ART-women were more frequently primiparous, whereas the prevalence of previous GDM was higher in SC-women. The prevalence of GDM in the whole cohort was 36.1% and was higher in ART-women (52.3% vs. 23.4%; p < 0.0001). In the whole cohort, on multivariate analysis, family history of diabetes (OR 1.67; 95% CI: 1.03-2.69), previous GDM (OR 7.05; 95% CI: 2.92-17.04), pre-pregnancy obesity (OR 2.72; 95% CI 1.21-6.13), and ART (OR 4.14; 95% CI 2.65-6.48) were independent risk factors for GDM. Among ART-women, age over 40 years was associated with GDM. Preterm delivery was more common in ART-women; gestational week at delivery, birth weight, ponderal index, and Apgar score were lower in ART-women than in SC-women, both in the whole cohort and in GDM women. CONCLUSIONS: Among women undergoing ART treatment, at least one in two develops GDM. ART appears to be an independent risk factor for GDM in single pregnancies, particularly above the age of 40. ART treatment seems to be associated with an increased rate of preterm delivery and lower neonatal birth weight and Apgar score, especially in GDM women. CLINICAL TRIAL REGISTRATION: The study was not registered as it is an observational retrospective evaluation.

Insecticidal effect of Eucalyptus globulus and Rosmarinus officinalis essential oils on a stored food pest Ephestia kuehniella (Lepidoptera, Pyralidea).

For the purpose of evaluating the local heritage of eastern Numidia, an ethnobotanical survey was conducted on a population located in the province (department) of El-Tarf (North-East of Algeria) on a frequency of use of two plants known in traditional health; Eucalyptus globulus (Myrtaceae) and Rosmarinus officinalis (Lamiaceae). After processing data, our results show a female dominance when using these plants on a fairly advanced age group (40 to 60 years old). These plants are used by the people at their fresh state and deem the leaf as the most used part for therapeutic and cosmetic purposes. Furthermore, steam baths and infusion remain the most widespread preparation methods. Most consumers use these plants to treat influenza, respiratory illnesses as well as diseases of the digestive tract. GC-MS of essential oils extracted from the plants studied disclose a dominance of the alcohols portrayed by the monoterpenes (42.73%), sesquiterpenes (32.6%) and oxides (10.48%) in E. globulus. Data also indicate a high content of oxides (38.11%) monoterpene alcohols (20.43%) and monoterpenes (19.70%) in R.officinalis. Toxicological contact tests were achieved on a store-products pest Ephestia kuehniella. The test results were assessed with E.globulus (LC50=0.013; LC95=0.081 µl/cm2) and R.officinalis (LC50=0.011; LC95=0.059 µl/cm2). The lethal time changes according to the dose used and the tested plant. In E.globulus, we observe (concentration: 0.005 µl/cm2; LT50=56.2 h), (Concentration: 0.01 µl/cm2; LT50=49.53h) and (Concentration: 0.04µl/cm2; LT50=20.93h). Whereas in R.officinalis, we recorded (Concentration: 0.005 µl/cm2; LT50=55.7h), (Concentration: 0.01µl/cm2; LT50=54.99 h) and (Concentration: 0.04µl/cm2; LT50=29.13 h). The bioinsecticide has also been administered by fumigation and underpins toxicity by the reduction of adults longevity in E.kuehniella with R.officinalis (LC50=4.03 µl/l air; LC95=14.73 µl/l air) and E.globulus (LC50=7.76 µl/lair; LC95=21.23 µl/l air). In addition, the tested plants show an outstanding repellent effect as long as E.globulus and  R.officinalis essential oils respectively demonstrate a slightly repellent power at 42.22% (RD50=0.09 µl/cm2 ; RD95=0.24 µl/cm2) and repellent at 60.00% (RD50=0.06 µl/cm2 ; RD95= 0.35 µl/cm2) towards E.kuehniella adults. The plant resources represent a genuine reserve of bioactive molecules, which can create solutions to sustainable development issues. These plants might be the source of new molecules of combat against some pests in order to protect human health and safeguard the environment.

Short sleep duration and risk of gestational diabetes.

ObjectiveSleep disturbances and short sleep duration are common in pregnancy and might contribute to the development of hyperglycemia. Therefore, we evaluated the association of sleep disturbances and gestational diabetes (GDM) in a cohort of women.MethodsWe collected data of 386 women consecutively screened for GDM in 2019 by 75 gr OGTT, according with IDPSG criteria. Pittsburgh Sleep Quality Index (PSQI) questionnaire was used to assess self-reported poor sleep quality (PSQI score >5) and short nocturnal sleep duration (<6 h).ResultsOf 386 women, 148 (38.3%) had poor sleep quality and 87 (22.5%) short sleep duration. GDM prevalence was 26.9%. There was no difference in GDM prevalence between women with poor or good sleep quality (26% vs. 28%; n.s.), while GDM was more frequent in women with short sleep duration (35.6% vs. 24.4%; p = 0.038). On univariate logistic regression analysis, short sleep duration (OR 1.71; 95%CI: 1.03-2.86; p = 0.039), previous GDM (OR 3.52; 95%CI: 1.83-6.76; p < 0.0001), family history of diabetes (OR 1.96; 95%CI: 1.21-3.91; p = 0.007), pre-pregnancy overweight (OR 1.85; 95%CI: 1.06-3.23; p = 0.031) or obesity (OR 2.56; 95%CI: 1.40-4.70; p = 0.002) were associated to GDM. However, after adjustment for confounders, short sleep duration did not persist as an independent risk factor for GDM (OR: 1.55; 95%CI: 0.91-2.65; ns).ConclusionsSleep disturbances are relative common among pregnant women. Although GDM seems more common among women with short sleep duration, this sleep disturbance does not seem to be an independent risk factor for GDM in women at high risk.

Beneficial effect of low-dose radioiodine ablation for Graves' orbitopathy: results of a retrospective study.

OBJECTIVE: Graves' orbitopathy (GO) reflects an autoimmune response against antigens expressed by the thyroid and orbital tissues. Elimination of thyroid antigens may be beneficial for GO. Total thyroid ablation (TTA) [thyroidectomy (Tx), followed by 30 mCi of radioiodine] was shown to exert a beneficial effect on GO following intravenous glucocorticoids (ivGC) compared with Tx alone. Here, we investigated retrospectively whether TTA performed with a 15 mCi of radioiodine still maintains advantages over Tx. METHODS: Thirty-two subjects, 13 treated with TTA (performed with 15 mCi of radioiodine) and 19 with Tx alone, all with moderately severe, active GO, treated with ivGC, were studied. The primary objective was the outcome of GO at 24 weeks based on a composite evaluation. RESULTS: The two groups did not differ at baseline in terms of sex, age, smoking habits, TSH, anti-TSH receptor autoantibodies, GO duration and eye features. The proportion of GO responders at 24 weeks was greater in the TTA (61.5%) than in the Tx group (26.3%, P = 0.046). In contrast, GO outcome at 48 weeks did not differ between the two groups (69.2% vs 52.6% of responder in TTA and Tx group, respectively). The outcome of the individual GO features did not differ between the two groups both a 24 and 48 months. CONCLUSIONS: The advantage of total thyroid ablation seems to be a more rapid response for GO to ivGC treatment. Prospective, randomized studies in a larger number of subjects are needed to confirm our findings.

DNA-Mediated Self-Assembly of Plasmonic Antennas with a Single Quantum Dot in the Hot Spot.

DNA self-assembly is a powerful tool to arrange optically active components with high accuracy in a large parallel manner. A facile approach to assemble plasmonic antennas consisting of two metallic nanoparticles (40 nm) with a single colloidal quantum dot positioned at the hot spot is presented here. The design approach is based on DNA complementarity, stoichiometry, and steric hindrance principles. Since no intermediate molecules other than short DNA strands are required, the structures possess a very small gap (≈ 5 nm) which is desired to achieve high Purcell factors and plasmonic enhancement. As a proof-of-concept, the fluorescence emission from antennas assembled with both conventional and ultrasmooth spherical gold particles is measured. An increase in fluorescence is obtained, up to ≈30-fold, compared to quantum dots without antenna.

Accumulation of Azelaic Acid in Xylella fastidiosa-Infected Olive Trees: A Mobile Metabolite for Health Screening.

Monitoring Xylella fastidiosa is critical for eradicating or at least containing this harmful pathogen. New low-cost and rapid methods for early detection capability are very much needed. Metabolomics may play a key role in diagnosis; in fact, mobile metabolites could avoid errors in sampling due to erratically distributed pathogens. Of the various different mobile signals, we studied dicarboxylic azelaic acid (AzA) which is a key molecule for biotic stress plant response but has not yet been associated with pathogens in olive trees. We found that infected Olea europaea L. plants of cultivars Cellina di Nardò (susceptible to X. fastidiosa) and Leccino (resistant to the pathogen) showed an increase in AzA accumulation in leaf petioles and in sprigs by approximately seven- and sixfold, respectively, compared with plants negative to X. fastidiosa or affected by other pathogens. No statistically significant variation was found between the X. fastidiosa population level and the amount of AzA in either of the plant tissues, suggesting that AzA accumulation was almost independent of the amount of pathogen in the sample. Furthermore, the association of AzA with X. fastidiosa seemed to be reliable for samples judged as potentially false-negative by quantitative polymerase chain reaction (cycle threshold [Ct] > 33), considering both the absolute value of AzA concentration and the values normalized on negative samples, which diverged significantly from control plants. The accumulation of AzA in infected plants was partially supported by the differential expression of two genes (named OeLTP1 and OeLTP2) encoding lipid transport proteins (LTPs), which shared a specific domain with the LTPs involved in AzA activity in systemic acquired resistance in other plant species. The expression level of OeLTP1 and OeLTP2 in petiole samples showed significant upregulation in samples positive to X. fastidiosa of both cultivars, with higher expression levels in positive samples of Cellina di Nardò compared with Leccino, whereas the two transcripts had a low expression level (Ct > 40) in negative samples of the susceptible cultivar. Although the results derived from the quantification of AzA cannot confirm the presence of the erratically distributed X. fastidiosa, which can be definitively assessed by traditional methods, we believe they represent a fast and cheap screening method for large-scale monitoring.

Evaluation of Phytochemical and Antioxidant Properties of 15 Italian Olea europaea L. Cultivar Leaves.

Olive leaf extracts are of special interest due to their proven therapeutic effects. However, they are still considered a by-product of the table olive and the oil industries. In order to learn possible ways of exploiting this waste for health purposes, we investigated the phytochemical profiles and antioxidant activities in the leaves of 15 Italian Olea europaea L. cultivars grown in the same pedoclimatic conditions. The phenolic profiles and amounts of their seven representative compounds were analyzed using HPLC ESI/MS-TOF. The antioxidant activities were determined using three different antioxidant assays (DPPH, ORAC, and superoxide anion scavenging assay). Wide ranges of total phenolic content (11.39-48.62 g GAE kg-1 dry weight) and antioxidant activities (DPPH values: 8.67-29.89 µmol TE mg-1 dry weight, ORAC values: 0.81-4.25 µmol TE mg-1 dry weight, superoxide anion scavenging activity values: 27.66-48.92 µmol TE mg-1 dry weight) were found in the cultivars. In particular, the cultivars Itrana, Apollo, and Maurino, showed a high amount of total phenols and antioxidant activity, and therefore represent a suitable natural source of biological compounds for use in terms of health benefits.

Sensing Picomolar Concentrations of RNA Using Switchable Plasmonic Chirality.

Detecting small sequences of RNA in biological samples such as microRNA or viral RNA demands highly sensitive and specific methods. Here, a reconfigurable DNA origami template has been used where a chiral arrangement of gold nanorods on the structure can lead to the generation of strong circular dichroism (CD). Switching of the cross-like DNA structure is achieved by the addition of nucleic acid sequences, which arrests the structure in one of the possible chiral states by specific molecular recognition. A specific sequence can thus be detected through the resulting changes in the plasmonic CD spectrum. We show the sensitive and selective detection of a target RNA sequence from the hepatitis C virus genome. The RNA binds to a complementary sequence that is part of the lock mechanism, which leads to the formation of a defined state of the plasmonic system with a distinct optical response. With this approach, we were able to detect this specific RNA sequence at concentrations as low as 100 pm.

Proximity-Induced H-Aggregation of Cyanine Dyes on DNA-Duplexes.

A wide variety of organic dyes form, under certain conditions, clusters know as J- and H-aggregates. Cyanine dyes are such a class of molecules where the spatial proximity of several dyes leads to overlapping electron orbitals and thus to the creation of a new energy landscape compared to that of the individual units. In this work, we create artificial H-aggregates of exactly two Cyanine 3 (Cy3) dyes by covalently linking them to a DNA molecule with controlled subnanometer distances. The absorption spectra of these coupled systems exhibit a blue-shifted peak, whose intensity varies depending on the distance between the dyes and the rigidity of the DNA template. Simulated vibrational resolved spectra, based on molecular orbital theory, excellently reproduce the experimentally observed features. Circular dichroism spectroscopy additionally reveals distinct signals, which indicates a chiral arrangement of the dye molecules. Molecular dynamic simulations of a Cy3-Cy3 construct including a 14-base pair DNA sequence verified chiral stacking of the dye molecules.

Photoresistance switching of plasmonic nanopores.

Fast and reversible modulation of ion flow through nanosized apertures is important for many nanofluidic applications, including sensing and separation systems. Here, we present the first demonstration of a reversible plasmon-controlled nanofluidic valve. We show that plasmonic nanopores (solid-state nanopores integrated with metal nanocavities) can be used as a fluidic switch upon optical excitation. We systematically investigate the effects of laser illumination of single plasmonic nanopores and experimentally demonstrate photoresistance switching where fluidic transport and ion flow are switched on or off. This is manifested as a large (∼ 1-2 orders of magnitude) increase in the ionic nanopore resistance and an accompanying current rectification upon illumination at high laser powers (tens of milliwatts). At lower laser powers, the resistance decreases monotonically with increasing power, followed by an abrupt transition to high resistances at a certain threshold power. A similar rapid transition, although at a lower threshold power, is observed when the power is instead swept from high to low power. This hysteretic behavior is found to be dependent on the rate of the power sweep. The photoresistance switching effect is attributed to plasmon-induced formation and growth of nanobubbles that reversibly block the ionic current through the nanopore from one side of the membrane. This explanation is corroborated by finite-element simulations of a nanobubble in the nanopore that show the switching and the rectification.

DNA translocations through solid-state plasmonic nanopores.

Nanopores enable label-free detection and analysis of single biomolecules. Here, we investigate DNA translocations through a novel type of plasmonic nanopore based on a gold bowtie nanoantenna with a solid-state nanopore at the plasmonic hot spot. Plasmonic excitation of the nanopore is found to influence both the sensor signal (nanopore ionic conductance blockade during DNA translocation) and the process that captures DNA into the nanopore, without affecting the duration time of the translocations. Most striking is a strong plasmon-induced enhancement of the rate of DNA translocation events in lithium chloride (LiCl, already 10-fold enhancement at a few mW of laser power). This provides a means to utilize the excellent spatiotemporal resolution of DNA interrogations with nanopores in LiCl buffers, which is known to suffer from low event rates. We propose a mechanism based on plasmon-induced local heating and thermophoresis as explanation of our observations.

De-intensification of basal-bolus insulin regimen after initiation of a GLP-1 RA improves glycaemic control and promotes weight loss in subjects with type 2 diabetes.

AIMS: To evaluate the impact of adding a glucagon-like peptide-1 receptor agonist (GLP-1 RA) in people with type 2 diabetes (T2D) in basal-bolus (BB) insulin regimen, on insulin requirement, HbA1c, weight loss up to 24 months. METHODS: Data on subjects with T2D on BB who initiated a GLP-1 RA have been retrospectively collected. HbA1c, body weight, and insulin dose were recorded at baseline, 6, 12, and 24 months after initiation of GLP-1 RA therapy. A linear mixed model for repeated measures was used to evaluate the changes in HbA1c, body weight, and insulin requirement over time. RESULTS: We included 156 subjects (63.5% males; age 62 ± 11 years, HbA1c 70 ± 22.0 mmol/mol; 8.6 ± 4.2%). Compared to baseline, HbA1c and body weight were significantly lower at 6 months after introducing a GLP-1RA and remained stable up to 24 months (all p < 0.0001 vs. baseline). At 24 months, 81% of subjects discontinued prandial insulin, while 38.6% discontinued basal insulin as well. Insulin requirement at baseline (aOR 0.144; 95% CI, 0.046-0.456; P = 0.001) was the only significant predictor of prandial insulin discontinuation. CONCLUSIONS: Replacing prandial insulin with GLP-1 RA is a valuable strategy to simplify the BB insulin regimen while improving glycaemic control and promoting weight loss in subjects with T2D.

Advances in diabetes management: have pregnancy outcomes in women with type 1 diabetes changed in the last decades?

AIMS: Over the recent years multiple therapeutic and management opportunities have been made available to treat pregnant women with Type 1 diabetes (T1DM). However, analyses assessing whether these different approaches may have any specific advantage/disadvantage in metabolic control and neonatal outcomes is still limited. The aim of this study was to compare metabolic control and neonatal outcomes in pregnant women with T1DM among different basal insulins (NPH vs. analogue), insulin administration ways [Multiple Daily Injections (MDI) vs. Continuous Subcutaneous Insulin Infusion (CSII)] and glucose monitoring systems [Self-Monitoring of Blood Glucose (SMBG) vs. real-time/intermittently scanned Continuous Glucose Monitoring (rtCGM/isCGM)]. METHODS: A retrospective analysis on metabolic data and neonatal outcomes of 136 T1DM pregnant women (76% on MDI, based on NPH (51%) or analogue (49%); 24% on CSII; 24% using rtCGM/isCGM), managed between 2008 and 2020, was performed, comparing different therapeutic approaches. RESULTS: Metabolic data and neonatal outcomes were comparable among women treated with different basal insulins. Women on CSII planned their pregnancy more frequently (82 vs. 60%; p = 0.043) and had better pregestational HbA1c (52 ± 5 vs. 60 ± 13 mmol/mol; p = 0.044) and first trimester HbA1c (48 ± 4 vs. 51 ± 8 mmol/mol; p = 0.047). Pregestational and first trimester HbA1c were also lower in women using rtCGM/isCGM (53 ± 8 vs. 58 ± 13 mmol/mol; p = 0.027 and 46 ± 5 vs. 51 ± 7 mmol/mol; p = 0.034, respectively). In the whole cohort, LGA risk was directly correlated to HbA1c at third trimester (correlation coefficient: 0.335, p = 0.001) and inversely correlated to the achievement of HbA1c target (≤6% [<42 mmol/mol]) at third trimester (correlation coefficient: - 0.367, p < 0.001). CONCLUSION: Treatment with insulin analogs didn't significantly change metabolic control and neonatal outcomes in T1DM women, while CSII and rtCGM/isCGM can optimize preconception and first trimester pregnancy glycemic control. Irrespective of the therapeutic management, third trimester HbA1c remains the strongest risk factor for LGA.

Use of non-nutritive-sweetened soft drink and risk of gestational diabetes.

In this observational study, we assessed the association between use of non-nutritive-sweetened soft drink (NNSSD) and risk of gestational diabetes (GDM) in 376 pregnant women consecutively screened for GDM, observing that NNSSD consumption is common among pregnant women and is associated with an increased risk of GDM, independently from traditional risk factors.

Disappearance of Anti-Thyroid Autoantibodies following Thymectomy in Patients with Myasthenia Gravis.

OBJECTIVES: The thymus plays a central role in immune tolerance, which prevents autoimmunity. Myasthenia gravis (MG) is commonly associated with thymoma or thymus hyperplasia, and it can coexist with autoimmune thyroid diseases. However, the role of the thymus in thyroid autoimmunity remains to be clarified, which we investigated here. STUDY DESIGN: The study design entailed the inclusion of consecutive MG patients and the measurement of anti-thyroid autoantibodies at baseline and, limited to autoantibody-positive patients, also at 24 and 48 weeks. One hundred and seven MG patients were studied. The main outcome measure was the behaviour of anti-thyroglobulin autoantibodies (TgAbs) and anti-thyroperoxidase autoantibodies (TPOAbs) over time in relation to thymectomy. RESULTS: Serum TgAbs and/or TPOAbs were detected in ∼20% of patients in the absence of thyroid dysfunction. The prevalence of positive serum TgAbs and/or TPOAbs decreased significantly (p = 0.002) over the follow-up period in patients who underwent thymectomy, but not in patients who were not thymectomized. When the analysis was restricted to TgAbs or TPOAbs, findings were similar. On the same line, there was a general trend towards a reduction in the serum concentrations of anti-thyroid autoantibodies in patients who underwent thymectomy, which was significant for TPOAbs (p = 0.009). CONCLUSIONS: Our findings suggest a role of the thymus in the maintenance of humoral thyroid autoimmunity.

Screening of Olive Biodiversity Defines Genotypes Potentially Resistant to Xylella fastidiosa.

The recent outbreak of the Olive Quick Decline Syndrome (OQDS), caused by Xylella fastidiosa subsp. pauca (Xf), is dramatically altering ecosystem services in the peninsula of Salento (Apulia Region, southeastern Italy). Here we report the accomplishment of several exploratory missions in the Salento area, resulting in the identification of thirty paucisymptomatic or asymptomatic plants in olive orchards severely affected by the OQDS. The genetic profiles of such putatively resistant plants (PRPs), assessed by a selection of ten simple sequence repeat (SSR) markers, were compared with those of 141 Mediterranean cultivars. Most (23) PRPs formed a genetic cluster (K1) with 22 Italian cultivars, including 'Leccino' and 'FS17', previously reported as resistant to Xf. The remaining PRPs displayed relatedness with genetically differentiated germplasm, including a cluster of Tunisian cultivars. Markedly lower colonization levels were observed in PRPs of the cluster K1 with respect to control plants. Field evaluation of four cultivars related to PRPs allowed the definition of partial resistance in the genotypes 'Frantoio' and 'Nocellara Messinese'. Some of the PRPs identified in this study might be exploited in cultivation, or as parental clones of breeding programs. In addition, our results indicate the possibility to characterize resistance to Xf in cultivars genetically related to PRPs.

Secondary Metabolites in Xylella fastidiosa-Plant Interaction.

During their evolutionary history, plants have evolved the ability to synthesize and accumulate small molecules known as secondary metabolites. These compounds are not essential in the primary cell functions but play a significant role in the plants' adaptation to environmental changes and in overcoming stress. Their high concentrations may contribute to the resistance of the plants to the bacterium Xylella fastidiosa, which has recently re-emerged as a plant pathogen of global importance. Although it is established in several areas globally and is considered one of the most dangerous plant pathogens, no cure has been developed due to the lack of effective bactericides and the difficulties in accessing the xylem vessels where the pathogen grows and produces cell aggregates and biofilm. This review highlights the role of secondary metabolites in the defense of the main economic hosts of X. fastidiosa and identifies how knowledge about biosynthetic pathways could improve our understanding of disease resistance. In addition, current developments in non-invasive techniques and strategies of combining molecular and physiological techniques are examined, in an attempt to identify new metabolic engineering options for plant defense.

Biochemical Changes in Leaves of Vitis vinifera cv. Sangiovese Infected by Bois Noir Phytoplasma.

Bois noir is a disease associated with the presence of phytoplasma 'Candidatus Phytoplasma solani' belonging to the Stolbur group (subgroup 16SrXII-A), which has a heavy economic impact on grapevines. This study focused on the changes induced by phytoplasma in terms of the profile and amount of secondary metabolites synthesized in the phenylpropanoid pathway in leaves of Vitis vinifera L. red-berried cultivar Sangiovese. Metabolic alterations were assessed according to the disease progression through measurements of soluble sugars, chlorophyll, and phenolic compounds produced by plant hosts, in response to disease on symptomatic and asymptomatic Bois noir-positive plants. Significant differences were revealed in the amount of soluble sugars, chlorophyll, and accumulation/reduction of some compounds synthesized in the phenylpropanoid pathway of Bois noir-positive and negative grapevine leaves. Our results showed a marked increase in phenolic and flavonoid production and a parallel decrease in lignin content in Bois noir-positive compared to negative leaves. Interestingly, some parameters (chlorophyll a, soluble sugars, total phenolic or flavonoids content, proanthocyanidins, quercetin) differed between Bois noir-positive and negative leaves regardless of symptoms, indicating measurable biochemical changes in asymptomatic leaves. Our grapevine cultivar Sangiovese results highlighted an extensive modulation of the phenylpropanoid biosynthetic pathway as a defense mechanism activated by the host plant in response to Bois noir disease.

Molecular Effects of Xylella fastidiosa and Drought Combined Stress in Olive Trees.

Due to global climate change, complex combinations of stresses are expected to occur, among which the interaction between pathogens and drought stress may have a significant effect on growth and yield. In this study, the Xylella fastidiosa (Xf)-resistant cultivar Leccino and the susceptible one Cellina di Nardò were subjected to (a) individual drought stress, (b) Xf infection and (c) combination of both stress conditions. Here we report the physiological response to stresses in water content in leaves and the modulation in the expression level of seven genes responsive to plant water status and pathogen infection. In Xf-resistant plants, higher expression levels are reported for genes belonging to ROS-scavenging systems and for genes involved in pathogen stress (pathogenesis-related, PR, and leucine-rich repeat genes, LRR-RLK). However, PR and LRR-RLK were not further induced by water deficit. Interestingly, the genes related to drought response (aquaporin, PIP2.1, dehydration responsive element binding, DREB, and dehydrin, DHN), which induction was higher in Cellina di Nardò compared to Leccino during drought stress, was poorly induced in Xf-susceptible plants when Xf occur. Conversely, DHN was induced by Xf presence in Leccino. These results were consistent with observations on water content. Indeed, response was similar in Leccino regardless kind of stress or combination, whereas a strong reduction was observed in Xf-susceptible plants infected by Xf or in presence of combined stresses. Thus, the reported findings indicate that resistance of Leccino to Xf could be linked to its lower resistance to water stress, probably leading to the activation of alternative defense pathways that support the plant in Xf response.