Genome editing for healthy crops: traits, tools and impacts.

Crop cultivars in commercial use have often been selected because they show high levels of resistance to pathogens. However, widespread cultivation of these crops for many years in the environments favorable to a pathogen requires durable forms of resistance to maintain "healthy crops". Breeding of new varieties tolerant/resistant to biotic stresses by incorporating genetic components related to durable resistance, developing new breeding methods and new active molecules, and improving the Integrated Pest Management strategies have been of great value, but their effectiveness is being challenged by the newly emerging diseases and the rapid change of pathogens due to climatic changes. Genome editing has provided new tools and methods to characterize defense-related genes in crops and improve crop resilience to disease pathogens providing improved food security and future sustainable agricultural systems. In this review, we discuss the principal traits, tools and impacts of utilizing genome editing techniques for achieving of durable resilience and a "healthy plants" concept.

CRISPR/Cas-mediated plant genome editing: outstanding challenges a decade after implementation.

The discovery of the CRISPR/Cas genome-editing system has revolutionized our understanding of the plant genome. CRISPR/Cas has been used for over a decade to modify plant genomes for the study of specific genes and biosynthetic pathways as well as to speed up breeding in many plant species, including both model and non-model crops. Although the CRISPR/Cas system is very efficient for genome editing, many bottlenecks and challenges slow down further improvement and applications. In this review we discuss the challenges that can occur during tissue culture, transformation, regeneration, and mutant detection. We also review the opportunities provided by new CRISPR platforms and specific applications related to gene regulation, abiotic and biotic stress response improvement, and de novo domestication of plants.

Ectomycorrhizal Fungi Modulate Pedunculate Oak's Heat Stress Responses through the Alternation of Polyamines, Phenolics, and Osmotica Content.

The physiological and biochemical responses of pedunculate oaks (Quercus robur L.) to heat stress (HS) and mycorrhization (individually as well in combination) were estimated. One-year-old Q. robur seedlings were grown under controlled conditions in a pot experiment, inoculated with a commercial inoculum of ectomycorrhizal (ECM) fungi, and subjected to 72 h of heat stress (40 °C/30 °C day/night temperature, relative humidity 80%, photoperiod 16/8 h) in a climate chamber, and they were compared with seedlings that were grown at room temperature (RT). An in-depth analysis of certain well-known stress-related metrics such as proline, total phenolics, FRAP, ABTS, non-protein thiols, and lipid peroxidation revealed that mycorrhized oak seedlings were more resistant to heat stress (HS) than non-mycorrhized oaks. Additionally, levels of specific polyamines, total phenolics, flavonoids, and condensed tannins as well as osmotica (proline and glycine betaine) content were measured and compared between four treatments: plants inoculated with ectomycorrhizal fungi exposed to heat stress (ECM-HS) and those grown only at RT (ECM-RT) versus non-mycorrhized controls exposed to heat stress (NM-HS) and those grown only at room temperature (NM-RT). In ectomycorrhiza inoculated oak seedlings, heat stress led to not only a rise in proline, total phenols, FRAP, ABTS, non-protein thiols, and lipid peroxidation but a notable decrease in glycine betaine and flavonoids. Amounts of three main polyamines (putrescine, spermine, and spermidine) were quantified by using high-performance liquid chromatography coupled with fluorescent detection (HPLC/FLD) after derivatization with dansyl-chloride. Heat stress significantly increased putrescine levels in non-mycorrhized oak seedlings but had no effect on spermidine or spermine levels, whereas heat stress significantly increased all inspected polyamine levels in oak seedlings inoculated with ectomycorrhizal inoculum. Spermidine (SPD) and spermine (SPM) contents were significantly higher in ECM-inoculated plants during heat stress (approximately 940 and 630 nmol g-1 DW, respectively), whereas these compounds were present in smaller amounts in non-mycorrhized oak seedlings (between 510 and 550 nmol g-1 DW for Spd and between 350 and 450 nmol g-1 DW for Spm). These findings supported the priming and biofertilizer roles of ectomycorrhizal fungi in the mitigation of heat stress in pedunculate oaks by modification of polyamines, phenolics, and osmotica content.

Biotic threats for 23 major non-native tree species in Europe.

For non-native tree species with an origin outside of Europe a detailed compilation of enemy species including the severity of their attack is lacking up to now. We collected information on native and non-native species attacking non-native trees, i.e. type, extent and time of first observation of damage for 23 important non-native trees in 27 European countries. Our database includes about 2300 synthesised attack records (synthesised per biotic threat, tree and country) from over 800 species. Insects (49%) and fungi (45%) are the main observed biotic threats, but also arachnids, bacteria including phytoplasmas, mammals, nematodes, plants and viruses have been recorded. This information will be valuable to identify patterns and drivers of attacks, and trees with a lower current health risk to be considered for planting. In addition, our database will provide a baseline to which future impacts on non-native tree species could be compared with and thus will allow to analyse temporal trends of impacts.

Botryosphaeriaceae associated with the die-back of ornamental trees in the Western Balkans.

Extensive die-back and mortality of various ornamental trees and shrubs has been observed in parts of the Western Balkans region during the past decade. The disease symptoms have been typical of those caused by pathogens residing in the Botryosphaeriaceae. The aims of this study were to isolate and characterize Botryosphaeriaceae species associated with diseased ornamental trees in Serbia, Montenegro, Bosnia and Herzegovina. Isolates were initially characterized based on the DNA sequence data for the internal transcribed spacer rDNA and six major clades were identified. Representative isolates from each clade were further characterized using DNA sequence data for the translation elongation factor 1-alpha, ß-tubulin-2 and large subunit rRNA gene regions, as well as the morphology of the asexual morphs. Ten species of the Botryosphaeriaceae were identified of which eight, i.e., Dothiorella sarmentorum, Neofusicoccum parvum, Botryosphaeria dothidea, Phaeobotryon cupressi, Sphaeropsis visci, Diplodia seriata, D. sapinea and D. mutila were known taxa. The remaining two species could be identified only as Dothiorella spp. Dichomera syn-asexual morphs of D. sapinea, Dothiorella sp. 2 and B. dothidea, as well as unique morphological characters for a number of the known species are described. Based on host plants and geographic distribution, the majority of Botryosphaeriaceae species found represent new records. The results of this study contribute to our knowledge of the distribution, host associations and impacts of these fungi on trees in urban environments.

Fresh frozen plasma as a successful antidotal supplement in acute organophosphate poisoning.

Despite improvements to intensive care management and specific pharmacological treatments (atropine, oxime, diazepam), the mortality associated with organophosphate (OP) poisoning has not substantially decreased. The objective of this examination was to describe the role of fresh frozen plasma (FFP) in acute OP poisoning. After a deliberate ingestion of malathion, a 55-year-old male suffering from miosis, somnolence, bradycardia, muscular fasciculations, rales on auscultation, respiratory insufficiency, as well as from an inhibition of red blood cell acetylcholinesterase (AChE) and plasma butyrylcholinesterase (BuChE), was admitted to hospital. Malathion was confirmed in a concentration of 18.01 mg L(-1). Apart from supportive measures (including mechanical ventilation for four days), antidotal treatment with atropine, oxime-pralidoxime methylsulphate (Contrathion(R)), and diazepam was administered, along with FFP. The potentially beneficial effects of FFP therapy included a prompt increase of BuChE activity (from 926 IU L(-1) to 3277 IU L(-1); reference range from 7000 IU L(-1) to 19000 IU L(-1)) and a reduction in the malathion concentration, followed by clinical recovery. Due to BuChE replacement, albumin content, and volume restitution, FFP treatment may be used as an alternative approach in patients with acute OP poisoning, especially when oximes are not available.

Genetic polymorphisms of ADH1C and CYP2E1 and risk of oral squamous cell carcinoma.

OBJECTIVE: Several studies have suggested that the metabolism of alcohol is modulated by the polymorphisms in genes encoding ethanol-metabolizing enzymes, including alcohol dehydrogenase 1C, ADH1C, and cytochrome P450-dependent monooxygenase, CYP2E1. Genetic polymorphisms of ethanol-metabolizing enzymes may affect individual susceptibility to oral cancer. The purpose of this study was to investigate the associations between ADH1C and CYP2E1 gene polymorphisms with oral squamous cell carcinoma in an ethnically homogeneous Caucasian population. DESIGN: Case-control study. SETTING: Serbian national general hospital. SUBJECTS AND METHODS: The study was conducted on 123 oral cancer patients and a control group of 177 individuals of the Caucasian race and the same ethnicity, matched in age and gender, without previous cancer history. The control group consisted of 120 population-based and 57 hospital-based controls of heavy-drinking individuals. Genetic polymorphisms of ADH1C SspI, ADH1C HaeIII, CYP2E1 RsaI, and CYP2E1 Ins were determined by the polymerase chain reaction and restriction fragment length polymorphisms. RESULTS: After adjustment by potential confounders, the significant increase of oral cancer risk, independent of alcohol drinking, was observed in individuals with the variant ADH1C SspI*2/*2 genotype (odds ratio, 3.029; P = .014) and in combined ADH1C SspI*1/*2 and ADH1C SspI*2/*2 genotypes (odds ratio, 2.605; P = .002), compared to the ADH1C*1/1* wild type. The association of other polymorphisms under study was not observed. CONCLUSION: This study suggested that the ADH1C SspI polymorphism could play a significant role in the etiology of oral cancer, whereas ADH1C HaeIII, CYP2E1 RsaI, and CYP2E1 Ins could have minor influence.

[Rapid simultaneous determination of organophosphorus pesticides in human serum and urine by liquid chromatography-mass spectrometry].

BACKGROUND/AIM: Analysis of organophosphosphorus compounds and their metabolites in a biological material includes the use of numerous methods, covering both preparation of samples for analysis and their identification that is considered to be very complex. Low concentrations monitoring requires implementation of highly sensitive analytical techniques. The aim of this study was to develop and validate an original and sensitive method for the detection and quantitation of organophosphorus pesticides (dimethoate, diazinon, malathion and malaoxon) in human biological matrices (serum, urine). METHODS: This method was based on a solid-phase extraction procedure, a chromatographic separation using an ACQUITY UPLC HSST3 column and mass spectrometric detection in the positive ion mode. Mobile phase: was consited of Solvent A (5 mM ammonium formate pH 3.0) and Solvent B (0.1% acetic formate in methanol), in a linear gradient (constant flow-rate 0.3 mL/min). RESULTS: The standard curve was linear in the range of 0.05-5.00 mg/L for malathion and malaoxon, 0.10-5.00 mg/L for dimethoate and 0.05-2.50 mg/L for diazinon. The correlation coefficient was r > or = 0.99. Extraction recoveries were satisfactory and ranged between 90-99%. The limits of detection (LOD) was between 0.007-0.07 mg/L and the limits of quantitation (LOQ) ranged between 0.022-0.085 mg/L. Intra- and interassay precision and accuracy were satisfactory for all of the pesticides analyzed. CONCLUSION: The method of liquid chromatography-mass spectrometry is simple, accurate, and useful for the determination of organophosphorus pesticides in both clinical and forensic toxicology.

Bioequivalence assessment of the two brands of glimepiride tablets.

BACKGROUND/AIM: Glimepiride, as an antidiabetic from the group of sulfonylurea, is administered perorally in the treatment of diabetes mellitus. The aim of this study was to compare pharmacokinetic profiles and relative bioavailabilities of the two oral formulations of glimepiride, generic and innovator tablets, after a single dose of the active drug. METHODS: An oral dose of 6 mg glimepiride was given under fasting conditions to 24 healthy volunteers. A one-week washout period was applied between the two consecutive periods. The serum samples obtained before dosing, and at various time points up to 48 hours, were analyzed for glimepiride concentration using the validated high-performance liquid chromatographic method with ultraviolet detection. Pharmacokinetic parameters representing early (maximal concentration, time to reach maximal concentration) and total exposure (area under the curve from the time 0 to the infinite time) to glimepiride were obtained and further analyzed using the multifactorial analysis of variance and the non-parametric Wilcoxon signed ranks test. Comparison of the secondary kinetic variables was only descriptive. RESULTS: The point estimates of the ratios of geometric means (test/reference) of maximal concentrations and areas under the curve were 1.046 (90% confidence interval: 0.906-1.208) and 1.022 (90% confidence interval: 0.856-1.220), respectively, while the median values of times to reach maximal concentration, at 5% level of significance, did not differ significantly. Both formulations were well tolerated. Transient mild hypoglycaemia, which had been noted in 6 participants, resolved spontaneously within 30-60 minutes. CONCLUSION: Since all the parametric 90% confidence intervals for the log-transformed main variables of glimepiride were within the 0.80 and 1.25 interval, accepted as the definition of bioequivalence, and the differences in times to reach maximal concentration also did not reach statistical significance, studied tablets were considered bioequivalent.