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This study investigated the antioxidant activity of gum Arabic (GA) during androgenesis in barley anthers. After stress pretreatment the anthers were cultured in the presence of 10 mg L−1 GA (Gm) or on control medium (Cm) and compared with respect to activity of selected antioxidant and respiratory enzymes and endogenous hydrogen peroxide (H2O2) content. The anthers from Cm and Gm differed in the strategy against H2O2 overproduction, in that the total peroxidase (POX) activity and the number of POX isoforms were significantly higher in Gm- than in Cm-cultured material. High POX activity on Gm paralleled with H2O2 decrease, suggesting the utilization of this chemical for the POX-mediated cell wall formation and reconstruction during growth of multicellular structures. The total superoxide dismutase (SOD) activity on Cm and Gm were at similar level for most of the culture period but the activity of MnSOD was dozen times higher on Gm and this coincided with high activity of fumarase and cytochrome c oxidase. It indicates close interplay between efficient antioxidative protection and high metabolic rate accompanying efficient androgenesis. Mass spectrometry analysis confirmed the presence of POX and other antioxidative and defense enzymes in protein fraction of GA used in the experiments, however as revealed by 2,2-diphenyl-1-picrylhydrazyl assay, the Gm and Cm displayed similar total antioxidant capacity. Thus, the effect of GA on androgenic cultures of barley can be linked to its influence on the activity of anther antioxidant system, rather than its native antioxidative properties.Key messageThis study shows a high activity of antioxidant enzymes in barley anthers exposed to gum Arabic. Effective ROS scavenging coincides with high respiratory activity of anthers and effective androgenesis.

Changes in malate concentration and activity of NADP-dependent malic enzyme were observed as the effect of Botrytis cinerea infection of C 3 or CAM-performing Mesembryanthemum crystallinum p lants. Biotic stress applied on C 3 plants led to increase in malate concentration during the night and in consequence it led to increase in Δ-malate (day/night fluctuations) in infected leaves on the 2nd day post infection (dpi). It corresponded with induction of additional isoform of NADP-malic enzyme (NADP-ME3). On the contrary, CAM-performing M. crystallinum plants exhibited decrease in malate concentration and decay in its diurnal fluctuations as a reaction to B. cinerea infection. This correlated with significant decrease in activities of NADP-malic enzyme isoforms on the 2nd dpi as well as no fluctuations in their activities on the 9th dpi. Presented results point out to differences between C 3 and CAM plants in the direction of changes in primary metabolism providing energy, reducing equivalents and carbon skeletons for defense responses to halt the pathogen growth.

The effects of Bipolaris sorokiniana inoculation on accumulation of hydrogen peroxide and changes in the activities of superoxide dismutase (SOD), catalase (CAT), non-specific peroxidase (PX) and β-1,3-glucanase enzymes in leaves of differentially resistant spring barley and meadow fescue were investigated in this study. Hydrogen peroxide accumulated slightly in inoculated barley leaves 24 hours after inoculation, and its accumulation after 48 hours of pathogenesis remained week around sites of infection. In leaves of fescue, which is more resistant to B. sorokiniana, accumulation of H 2 O 2 was faster and stronger in comparison to barley. A slight increase in SOD activity was observed only in infected fescue. Catalase activity in infected barely leaves decreased significantly 48 hours after inoculation, while in fescue-infected plants CAT activity, following a slight decrease, remained similar to the control values. PX activity was considerable lower in inoculated barley leaves after 6 hours, but at 24 and 48 hours after inoculation its activity increased significantly compared to the control. In inoculated fescue leaves activity of PX was higher at 6 and 24 hours compared to the control, while at 48 hours PX activity was strongly inhibited. β-1,3-Glucanase activity in inoculated barley plants did not differ from that of the control, while in infected fescue leaves it increased significantly 48 hours after inoculation. Based on the results, we suggest that the strong accumulation of H 2 O 2 , changes in antioxidant levels, together with the significant increase of β-1,3-Glucanase activity in infected fescue leaves, plays an important role in fescue's greater resistance to B. sorokiniana.

Callus was obtained from hypocotyls of Mesembryanthemum crystallinum seedlings cultured on two types of medium--germination medium (GM) and callus induction medium (CIM). Following subculture on shoot induction medium SIM1, the callus formed on CIM medium regenerated roots or somatic embryos, while that obtained on GM medium was non-regenerative. The activities of CuZn-superoxidase dismutase (SOD) were comparable in all calli, but the activities of FeSOD and MnSOD varied according to the activity of photosystem II and the regenerative potential of the tissues. Catalase (CAT) activity was related to H2O2 concentration and affected by both the culture conditions and the morphogenic potential of the calli. The possible role of CAT, SODs and H2O2 in the regeneration of M. crystallinum from callus is discussed.

The incidence of polyspermy in lamb oocytes matured and fertilized in vitro is very high and this results in a reduced developmental potential of embryos arising from them. We have attempted to produce oocytes more resistant to this fertilization anomaly. The oocytes from prepubertal lambs 7–12 weeks old were matured in a medium supplemented with various blood sera and oviductal fluid and fertilized in vitro . Significantly higher monospermic penetration was found in a medium supplemented with BSA – 3 mg/ml (63.9%) and OF – 20% concentration (55.8%). Lower monospermy was recorded in the presence of 10% LS (44.6%) or 10% SS (40.8%), and particularly in a medium with 10% FCS (26.9%). In contrast, high monospermy (78.7%) was observed in oocytes from adult donors matured and fertilized in an identical system. In another set of experiments we estimated whether polyspermy can be reduced by improvement of the cytoplasmic maturation of prepubertal oocytes using a two-step maturation protocol. After artificial arrest of the maturation for 24 h with a specific cdk inhibitor – BL-I, 50 µ µM – more than 80% oocytes from prepubertal and adult donors did not resume meiosis. When incubated thereafter in a drug-free medium for another 24 h, the oocytes of both categories progressed to MII in the rate comparable with control (80% to 90% MII). However, after fertilization no significant differences in the level of monospermic penetration was recorded between the arrested group (59.8%) and control (58.8%), both matured in the presence BSA, and 46.6% and 52.3% after treatment with OF. Also, no significant difference was observed between the arrested and control oocytes from adult donors (72.6% and 84.8%, respectively). These results suggest that high polyspermy in prepubertal oocytes is caused by developmental imperfection and can’t be fully eliminated either by modifying the composition of culture media or by prolongation of the culture interval.

The effects of Bipolaris sorokiniana inoculation on accumulation of hydrogen peroxide and changes in the activities of superoxide dismutase (SOD), catalase (CAT), non-specific peroxidase (PX) and β -1,3-glucanase enzymes in leaves of differentially resistant spring barley and meadow fescue were investigated in this study. Hydrogen peroxide accumulated slightly in inoculated barley leaves 24 hours after inoculation, and its accumulation after 48 hours of pathogenesis remained week around sites of infection. In leaves of fescue, which is more resistant to B. sorokiniana , accumulation of H 2 O 2 was faster and stronger in comparison to barley. A slight increase in SOD activity was observed only in infected fescue. Catalase activity in infected barely leaves decreased significantly 48 hours after inoculation, while in fescue-infected plants CAT activity, following a slight decrease, remained similar to the control values. PX activity was considerable lower in inoculated barley leaves after 6 hours, but at 24 and 48 hours after inoculation its activity increased significantly compared to the control. In inoculated fescue leaves activity of PX was higher at 6 and 24 hours compared to the control, while at 48 hours PX activity was strongly inhibited. β -1,3-Glucanase activity in inoculated barley plants did not differ from that of the control, while in infected fescue leaves it increased significantly 48 hours after inoculation. Based on the results, we suggest that the strong accumulation of H 2 O 2 , changes in antioxidant levels, together with the significant increase of β -1,3-Glucanase activity in infected fescue leaves, plays an important role in fescue’s greater resistance to B. sorokiniana .

The effects of Bipolaris sorokiniana inoculation on accumulation of hydrogen peroxide and changes in the activities of superoxide dismutase (SOD), catalase (CAT), non-specific peroxidase (PX) and β -1,3-glucanase enzymes in leaves of differentially resistant spring barley and meadow fescue were investigated in this study. Hydrogen peroxide accumulated slightly in inoculated barley leaves 24 hours after inoculation, and its accumulation after 48 hours of pathogenesis remained week around sites of infection. In leaves of fescue, which is more resistant to B. sorokiniana , accumulation of H 2 O 2 was faster and stronger in comparison to barley. A slight increase in SOD activity was observed only in infected fescue. Catalase activity in infected barely leaves decreased significantly 48 hours after inoculation, while in fescue-infected plants CAT activity, following a slight decrease, remained similar to the control values. PX activity was considerable lower in inoculated barley leaves after 6 hours, but at 24 and 48 hours after inoculation its activity increased significantly compared to the control. In inoculated fescue leaves activity of PX was higher at 6 and 24 hours compared to the control, while at 48 hours PX activity was strongly inhibited. β -1,3-Glucanase activity in inoculated barley plants did not differ from that of the control, while in infected fescue leaves it increased significantly 48 hours after inoculation. Based on the results, we suggest that the strong accumulation of H 2 O 2 , changes in antioxidant levels, together with the significant increase of β -1,3-Glucanase activity in infected fescue leaves, plays an important role in fescue’s greater resistance to B. sorokiniana .

Background Specialized clinical care for cystic fibrosis (CF) in Cyprus, a small island country, has been implemented since the 1990s. However, only recently, a national CF patient registry has been established for the systematic recording of patients’ data. In this study, we aim to present data on the epidemiological, genotypic and phenotypic features of CF patients in the country from the most recent data collection in 2019, with particular emphasis on notable rare or unique cases. Results Overall, data from 52 patients are presented, 5 of whom have deceased and 13 have been lost to follow-up in previous years. The mean age at diagnosis was 7.2 ± 12.3 years, and the mean age of 34 alive patients by the end of 2019 was 22.6 ± 13.2 years. Patients most commonly presented at diagnosis with acute or persistent respiratory symptoms (46.2%), failure to thrive or malnutrition (40.4%), and dehydration or electrolyte imbalance (32.7%). Sweat chloride levels were diagnostic (above 60 mmol/L) in 81.8% of examined patients. The most common identified mutation was p.Phe508del (F508del) (45.2%), followed by p.Leu346Pro (L346P) (6.7%), a mutation detected solely in individuals of Cypriot descent. The mean BMI and FEV 1 z-scores were 0.2 ± 1.3 and − 2.1 ± 1.7 across all age groups, respectively, whereas chronic Pseudomonas aeruginosa colonization was noted in 26.9% of patients. The majority of patients (74.5%) were eligible to receive at least one of the available CFTR modulator therapies. In 25% of patients we recovered rare or unique genotypic profiles, including the endemic p.Leu346Pro (L346P), the rare CFTR-dup2, the co-segregated c.4200_4201delTG/c.489 + 3A > G, and the polymorphism p.Ser877Ala. Conclusions CF patient registries are particularly important in small or isolated populations, such as in Cyprus, with rare or unique disease cases. Their operation is necessary for the optimization of clinical care provided to CF patients, enabling their majority to benefit from evolving advances in precision medicine.

This book contains current knowledge and the most recent developments in the field of halophyte biology, ecology, and potential uses. Halophytes are characterised as plants that can survive and complete their life cycle in highly saline environments. This book explores the adaptive mechanisms and special features of halophytes that allow them to grow in environments that are unsuitable for conventional crops and considers their role as a source of food, fuel, fodder, fibre, essential oils, and medicines.Halophytes and Climate Change includes coverage of:- Special morphological, anatomical, and physiological features of halophytes- Ion accumulation patterns and homeostasis in halophytes- Potential use of halophytes in the remediation of saline soil- Growth and physiological response and tolerance to toxicity and drought- Mangrove ecology, physiology, and adaptationWritten by a team of international authors and presented in full colour, this book is an essential resource for researchers in the fields of plant physiology, ecology, soil science, environmental science, botany, and agriculture.