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Norway maple and sycamore, two Acer genus species, have an important ecological value and different sensitivity to stressing factors being currently aggravated by climate change. Seedling growth is postulated to be the main barrier for successful plant establishment under the climate change scenarios. Therefore, the differences in redox regulation during the seedling performance of Norway maple and sycamore were investigated. Seeds of the two Acer species exhibited an identical high germination capacity, whereas seedling emergence was higher in sycamores. PCA analyses revealed that there is more diversification in the leaf characteristics than roots. Norway maple displayed a higher chlorophyll content index (CCI) with a similar leaf mass whereas sycamore seedlings exhibited a higher normalized difference vegetation index (NDVI), higher water content, higher root biomass and higher shoot height. Based on NDVI, sycamore seedlings appeared as very healthy plants, whereas Norway maple seedlings displayed a moderate healthy phenotype. Therefore, redox basis of seedling performance was investigated. The total pool of glutathione was four times higher in sycamore leaves than in Norway maple leaves and was reflected in highly reduced half-cell reduction potential of glutathione. Sycamore leaves contained more ascorbate because the content of its reduced form (AsA) was twice as high as in Norway maple. Therefore, the AsA/DHA ratio was balanced in sycamore leaves, reaching 1, and was halved in Norway maple leaves. Nicotinamide adenine dinucleotide phosphate content was twice as high in sycamore leaves than in Norway maples; however, its reduced form (NADPH) was predominant in Norway maple seedlings. Norway maple leaves exhibited the highest anabolic and catabolic redox charge. The higher reduction capacity and the activity of NADPH-dependent reductases in Norway maple leaves possibly resulted in higher CCI, whereas the larger root system contributed to higher NDVI in sycamore. The different methods of controlling redox parameters in Acer seedlings grown at controlled conditions provided here can be useful in understanding how tree species can cope with a changing environment in the future.

Changes in environmental factors, human impact, and interactions between them accelerate the extinction of woody species. Therefore, conservation programs are needed to protect endangered taxa. However, the relationship between climate, habitat fragmentation, and anthropogenic activities and their consequences are still not well understood. In this work, we aimed to evaluate the impact of climate change and human population density on the Buxus hyrcana Pojark distribution range, as well as the phenomenon of habitat fragmentation. Based on species occurrence data throughout the Hyrcanian Forests (north of Iran), the MAXENT model was employed to estimate the potential distribution and suitability changes. Morphological-spatial analysis (MSPA) and CIRCUITSCAPE were used to assess habitat fragmentation and its connectivity. According to the main results obtained from future scenarios, the potential range will significantly decrease due to the lack of suitable climatic conditions. Meanwhile, B. hyrcana may not be able to shift in potentially suitable areas because of human influence and geographic barriers. Under RCP scenarios the extent of the core area would be reduced and the edge/core ratio significantly increased. Altogether, we found negative effects of the environmental change and the human population density on the continuity of habitats of B. hyrcana. The results of the presented work may improve our knowledge connected with in situ and ex situ protection strategies.

Caspian poplar (Populus caspica Bornm.) is an endemic species from Hyrcanian forests and classified as endangered in Iran. However, there is little information about population genetic structure of remnant populations that could support the development of the suitable conservation strategy for this species. This study was designed to understand how anthropogenic and environmental factors have influenced the pattern of genetic diversity of P. caspica. We sampled 359 individuals from 20 populations. However, after removing the clonal ramets, the genetic parameters were calculated for 314 trees using 14 microsatellite markers. Nine populations showed a significant reduction in effective population size and a genetic bottleneck. The inbreeding coefficient (FIS) ranged from 0.02 to 0.11, and the pairwise FST from 0.018 to 0.224, indicating a low to high level of differentiation among populations. The average proportion of migrants was low (0.008), and it was revealed that the Alborz mountains are a major barrier to gene flow between P. caspica populations in the Hyrcanian forests. Resistance analysis showed that elevation is a significant barrier for gene flow across the eastern and western range of the species. STRUCTURE analysis showed the existence of at least two genetic clusters, whereas GENELAND estimated the number of clusters as three. We propose the maintenance of three natural management units to reduce the risk of extinction of this species in the near future.

The levels of methionine sulfoxide (MetO) and the abundances of methionine sulfoxide reductases (Msrs) were reported as important for the desiccation tolerance of Acer seeds. To determine whether the MetO/Msrs system is related to reactive oxygen species (ROS) and involved in the regulation of germination in orthodox and recalcitrant seeds, Norway maple and sycamore were investigated. Changes in water content, MetO content, the abundance of MsrB1 and MsrB2 in relation to ROS content and the activity of reductases depending on nicotinamide adenine dinucleotides were monitored. Acer seeds differed in germination speed&mdash, substantially higher in sycamore&mdash, hydration dynamics, levels of hydrogen peroxide, superoxide anion radicals (O2&bull, &minus, ) and hydroxyl radicals (&bull, OH), which exhibited peaks at different stages of germination. The MetO level dynamically changed, particularly in sycamore embryonic axes, where it was positively correlated with the levels of O2&bull, and the abundance of MsrB1 and negatively with the levels of &bull, OH and the abundance of MsrB2. The MsrB2 abundance increased upon sycamore germination, in contrast, it markedly decreased in Norway maple. We propose that the ROS&ndash, MetO&ndash, Msr redox system, allowing balanced Met redox homeostasis, participates in the germination process in sycamore, which is characterized by a much higher speed compared to Norway maple.

Seed germination is a complex process enabling plant reproduction. Germination was found to be regulated at the proteome, metabolome and hormonal levels as well as via discrete post-translational modification of proteins including phosphorylation and carbonylation. Redox balance is also involved but less studied.Acerseeds displaying orthodox and recalcitrant characteristics were investigated to determine the levels of redox couples of nicotinamide adenine dinucleotide (NAD) phosphate (NADP) and integrated with the levels of ascorbate and glutathione. NAD and NADP concentrations were higher in Norway maple seeds and exceptionally high at the germinated stage, being the most contrasting parameter between germinatingAcerseeds. In contrast, NAD(P)H/NAD(P)+ratios were higher in sycamore seeds, thus exhibiting higher reducing power. Despite distinct concentrations of ascorbate and glutathione, both seed types attained in embryonic axes and cotyledons had similar ratios of reduced/oxidized forms of ascorbate and half-cell reduction potential of glutathione at the germinated stage. Both species accomplished germination displaying different strategies to modulate redox status. Sycamore produced higher amounts of ascorbate and maintained pyridine nucleotides in reduced forms. Interestingly, lower NAD(P) concentrations limited the regeneration of ascorbate and glutathione but dynamically drove metabolic reactions, particularly in this species, and contributed to faster germination. We suggest that NAD(P) is an important player in regulating redox status during germination in a distinct manner in Norway maple and sycamore seeds.

Norway maple and sycamore produce desiccation-tolerant (orthodox) and desiccation-sensitive (recalcitrant) seeds, respectively. Drying affects reduction and oxidation (redox) status in seeds. Oxidation of methionine to methionine sulfoxide (MetO) and reduction via methionine sulfoxide reductases (Msrs) have never been investigated in relation to seed desiccation tolerance. MetO levels and the abundance of Msrs were investigated in relation to levels of reactive oxygen species (ROS) such as hydrogen peroxide, superoxide anion radical and hydroxyl radical (&bull, OH), and the levels of ascorbate and glutathione redox couples in gradually dried seeds. Peptide-bound MetO levels were positively correlated with ROS concentrations in the orthodox seeds. In particular, &bull, OH affected MetO levels as well as the abundance of MsrB2 solely in the embryonic axes of Norway maple seeds. In this species, MsrB2 was present in oxidized and reduced forms, and the latter was favored by reduced glutathione and ascorbic acid. In contrast, sycamore seeds accumulated higher ROS levels. Additionally, MsrB2 was oxidized in sycamore throughout dehydration. In this context, the three elements &bull, OH level, MetO content and MsrB2 abundance, linked together uniquely to Norway maple seeds, might be considered important players of the redox network associated with desiccation tolerance.

Desiccation tolerance is a developmental program enabling seed survival in a dry state and is common in seeds categorized as orthodox. We focused on NAD and its phosphorylated form (NADP) because their continual switching between reduced (NAD(P)H) and oxidized (NAD(P)+) forms is involved in the modulation of redox signaling and the determination of the reducing power and further antioxidant responses. Norway maple and sycamore seeds representing the orthodox and recalcitrant categories, respectively, were used as models in a comparison of responses to water loss. The process of desiccation up to 10% water content (WC) was monitored in Norway maple seeds, while dehydration up to 30% WC was monitored in desiccation-sensitive sycamore seeds. Norway maple and sycamore seeds, particularly their embryonic axes, exhibited a distinct redox status during dehydration and desiccation. High NADPH levels, NAD+ accumulation, low and stable NAD(P)H/NAD(P)+ ratios expressed as reducing power and high NADPH-dependent enzyme activity were reported in Norway maple seeds and were considered attributes of orthodox-type seeds. The contrasting results of sycamore seeds contributed to their low antioxidant capacity and high sensitivity to desiccation. NADPH deficiency, low NADPH-dependent enzyme activity and lack of NAD+ accumulation were primary features of sycamore seeds, with implications for their NAD(P)H/NAD(P)+ ratios and reducing power and with effects on many seed traits. Thus, we propose that the distinct levels of pyridine nucleotides and their redox status contribute to orthodox and recalcitrant phenotype differentiation in seeds by affecting cellular redox signaling, metabolism and the antioxidant system.

European beech is an important component of European lowland forests in terms of ecology, and produces irregular seeds categorized as intermediate due to their limited longevity. Removal of the excess of reactive oxygen species is crucial for redox homeostasis in growing plant tissues. Hydrogen peroxide (H2O2) is detoxified via the plant-specific ascorbate-glutathione cycle, and enzymatically, mainly by catalase (CAT). The reduced and oxidized (redox) forms of ascorbate (AsA, DHA) and glutathione (GSH, GSSG) decreased during maturation as the content of redox forms of nicotinamide adenine dinucleotide (NADH, NAD+) phosphate (NADPH, NADP+), cofactors of ascorbate–glutathione enzymes, declined and limited this cycle. The degree of oxidation of glutathione peaked at approximately 80%, at the exact time when the NADP content was the lowest and the NADPH/NADP+ ratio reached the highest values. The glutathione pool was reflected in changes in the NADP pool, both in embryonic axes (R2 = 0.61) and in cotyledons (R2 = 0.98). A large excess of NADPH was reported in embryonic axes, whereas cotyledons displayed more unified levels of NADP redox forms. As a result, anabolic redox charge and reducing power were higher in embryonic axes. CAT was recognized as two proteins, and the abundance of the 55 kDa protein was correlated with all redox forms of ascorbate, glutathione, NAD, and NADP, whereas the 37 kDa protein was oppositely regulated in embryonic axes and cotyledons. Here, we discuss the role of NAD(P) in the regulation of the ascorbate–glutathione cycle, catalase, and seed longevity concerning a putative role of NAD(P)H as a redox biomarker involved in predefining seed quality, because NAD(P)H-derived redox homeostasis was found to be better controlled in embryonic axes than cotyledons.

We examined the role of Helicobacter pylori infection as a cause of recurrent abdominal pain (RAP) among Iranian children in a population-based case-control study to determine the association between H. pylori infection and RAP among schoolchildren. A total of 1558 children aged 6-13 years were examined. Children with RAP confirmed by the Apley and Naish criteria were selected; 145 cases were selected for inclusion and were compared with 145 healthy children recruited from the same area. Both groups underwent stool antigen testing. The prevalence of RAP in the children tested was 9.3%. Children with RAP had a higher H. pylori infection rate than the control group (58.6% vs 44.8%) (OR = 1.744; 95% CI: 1.095-2.776). There was no significant difference between the RAP symptoms in children with positive stool test, i.e. infected with H. pylori, and those whose tests were negative. We identified H. pylori infection in more than 55% of the case group. Therefore, H. pylori infection can be considered an important factor for RAP in children.الألم البطني المتكرر في مرحلة الطفولة والعدوى بالملويَّة البوابية في جمهورية إيران الإسلامية.حسين علي محمدي، نسرين فولادي، فرهاد صالح زاده، شيرين علي بور، مهري جوادي.لقد درسنا دور العدوى بالملوية البوابية كسبب لألم البطني المتكرر عند الأطفال الإيرانين في دراسة حالات وشواهد سكانية المرتكز لتحديد العلاقة بن العدوى بالملوية البوابية وبن الألم البطني المتكرر عند تلاميذ المدارس. حيث جرى فحص ما مجموعه 1558 طفلاً تراوح أعمارهم بن 6 و 13 سنة. وجرى اختيار الأطفال الذين يعانون من ألم بطني متكرر مؤكَّد بحسب معيارَي آبلي ونيش؛ فاخترت 145 حالة لإدراجها في الدراسة، وقورنت مع 145 من الأطفال الأصحاء الذين تم اختيارهم من نفس المنطقة. وخضعت كلا الفئتن لاختبار التحري عن المستضد في الراز. فكان معدل وقوع الألم البطني المتكرر عند الأطفال الذين فُحصوا % 9.3. وكانت نسبة العدوى بالملوية البوابية عند الأطفال الذين يعانون من ألم بطني متكرر أعى مما هي عليه عند الفئة الشاهدة (% 58.6 مقابل %44.8) OR=1.744; 95% CI: (1.095–2.776. ولم يكن هناك فرق كبر بن أعراض الألم البطني المتكرر عند الأطفال الذين كان الراز لديهم إيجابياً – أي: المصابن بعدوى الملوية البوابية – وبن أولئك الذين كانت الاختبارات لديهم سلبية. ولقد تعرفنا عى وجود عدوى بالملوية البوابية عند أكثر من % 55 من فئة الحالات. وبالتالي يمكن اعتبار العدوى بالملوية البوابية عاماً مهاً من عوامل الإصابة بألم بطني متكرر عند في الأطفال.Douleur abdominale récurrente chez l’enfant et infection par Helicobacter pylori, République islamique d’Iran.Nous avons examiné le rôle de l’infection par Helicobacter pylori en tant que cause de douleur abdominale récurrente parmi des enfants iraniens au cours d’une étude cas-témoin populationnelle afin de déterminer l’association entre cette infection et la douleur abdominale récurrente chez les enfants scolarisés. Au total, 1558 enfants âgés de 6 à 13 ans ont été examinés. Des enfants souffrant d’une douleur abdominale récurrente confirmée selon les critères définis par Apley et Naish ont été sélectionnés : 145 cas répondant au critère d’inclusion ont été comparés avec 145 enfants en bonne santé de la même région. Les deux groupes ont été soumis à un test de recherche d’antigènes dans les selles. L’incidence de la douleur abdominale récurrente testée était de 9,3 %. Les enfants ayant une douleur abdominale récurrente présentaient un taux d’infection par H. pylori plus élevé que le groupe témoin (58,6 % contre 44,8 % ; OR = 1,744 et IC à 95 % : 1,095-2,776). Il n’y avait pas de différence significative entre les symptômes de douleur abdominale récurrente chez les enfants ayant des coprocultures positives, donc une infection par H. pylori, et ceux dont les tests étaient négatifs. Nous avons identifié une infection par H. pylori chez plus de 55 % d’enfants du groupe témoin. Par conséquent, l’infection par H. pylori peut être considérée comme un facteur important de douleur abdominale chez l’enfant.

Reactive oxygen species (ROS) are constantly produced by metabolically active plant cells. The concentration of ROS may determine their role, e.g., they may participate in signal transduction or cause oxidative damage to various cellular components. To ensure cellular homeostasis and minimize the negative effects of excess ROS, plant cells have evolved a complex antioxidant system, which includes ascorbic acid (AsA). AsA is a multifunctional metabolite with strong reducing properties that allows the neutralization of ROS and the reduction of molecules oxidized by ROS in cooperation with glutathione in the Foyer-Halliwell-Asada cycle. Antioxidant enzymes involved in AsA oxidation and reduction switches evolved uniquely in plants. Most experiments concerning the role of AsA have been performed on herbaceous plants. In addition to extending our understanding of this role in additional taxa, fundamental knowledge of the complex life cycle stages of woody plants, including their development and response to environmental factors, will enhance their breeding and amend their protection. Thus, the role of AsA in woody plants compared to that in nonwoody plants is the focus of this paper. The role of AsA in woody plants has been studied for nearly 20 years. Studies have demonstrated that AsA is important for the growth and development of woody plants. Substantial changes in AsA levels, as well as reduction and oxidation switches, have been reported in various physiological processes and transitions described mainly in leaves, fruits, buds, and seeds. Evidently, AsA exhibits a dual role in the photoprotection of the photosynthetic apparatus in woody plants, which are the most important scavengers of ozone. AsA is associated with proper seed production and, thus, woody plant reproduction. Similarly, an important function of AsA is described under drought, salinity, temperature, light stress, and biotic stress. This report emphasizes the involvement of AsA in the ecological advantages, such as nutrition recycling due to leaf senescence, of trees and shrubs compared to nonwoody plants.

Trauma has been considered an important factor of temporomandibular dysfunction (TMD) etiology. The aim of the present study was to compare the frequency of TMDs in various mandibular fractures.This was a retrospective cohort study. Mandibular fractures were subcategorized into 3 groups: group 1 had a unilateral condylar fracture, group 2 had a unilateral condylar fracture with a fracture of the contralateral body or angle of the mandible, and group 3 had a unilateral fracture of the body or angle of the mandible. TMD signs (click, pain) and maximum mouth opening (MMO) were the outcomes of the study, and fracture pattern was considered a predictor factor. Age, gender, and fixation methods were study variables. A χ(2) test was applied to compare TMD signs among groups. One-way analysis of variance was applied to compare MMO and age among groups.Ninety-nine patients in the 3 groups were examined for TMD signs. Results showed that 54.54% of patients in group 1, 69.69% of patients in group 2, and 24.24% of patients in group 3 had click in the temporomandibular joint (TMJ; unilaterally or bilaterally). Analysis of the data showed a significant difference among groups (P.05). According to the results, 24.24% of patients in group 1, 73.91% of patients in group 2, and 12.12% of patients in group 3 had pain at the TMJ (unilaterally or bilaterally). There was a significant difference among groups for pain (P.05). Analysis of the data did not show any difference for MMO among groups (P.05).Patients who had a condylar fracture and a contralateral angle or body fracture seemed to have more TMD signs than those with a unilateral fracture.