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821.
Jelena Cvetkovic Ilka Haferkamp Regina Rode Isabel Keller Benjamin Pommerrenig Oliver Trentmann Jacqueline Altensell Michaela Fischer-Stettler Simona Eicke Samuel C Zeeman H Ekkehard Neuhaus 《Plant physiology》2021,186(1):315
Maltose, the major product of starch breakdown in Arabidopsis (Arabidopsis thaliana) leaves, exits the chloroplast via the maltose exporter1 MEX1. Consequently, mex1 loss-of-function plants exhibit substantial maltose accumulation, a starch-excess phenotype and a specific chlorotic phenotype during leaf development. Here, we investigated whether the introduction of an alternative metabolic route could suppress the marked developmental defects typical for mex1 loss-of-function mutants. To this end, we ectopically expressed in mex1 chloroplasts a functional maltase (MAL) from baker’s yeast (Saccharomyces cerevisiae, chloroplastidial MAL [cpMAL] mutants). Remarkably, the stromal MAL activity substantially alleviates most phenotypic peculiarities typical for mex1 plants. However, the cpMAL lines contained only slightly less maltose than parental mex1 plants and their starch levels were, surprisingly, even higher. These findings point to a threshold level of maltose responsible for the marked developmental defects in mex1. While growth and flowering time were only slightly retarded, cpMAL lines exhibited a substantially improved frost tolerance, when compared to wild-types. In summary, these results demonstrate the possibility to bypass the MEX1 transporter, allow us to differentiate between possible starch-excess and maltose-excess responses, and demonstrate that stromal maltose accumulation prevents frost defects. The latter insight may be instrumental for the development of crop plants with improved frost tolerance.Expressing a yeast maltase in chloroplasts of the Arabidopsis maltose transporter mutant mex1 prevents the marked developmental defects typical for that mutant and enhances plant frost tolerance. 相似文献
822.
Jelena Veki Jasmina Ivanievi Aleksandra Zeljkovi Vesna Spasojevi-Kalimanovska Nataa Bogavac-Stanojevi Marija Mihajlovi Jelena Jana Sanja Vuj
i Milica Miljkovi Dejan Zujovi Jelena Kotur-Stevuljevi 《Journal of Medical Biochemistry》2020,39(4):467
BackgroundPropolis and N-acetylcysteine have positive impact on respiratory tract health. Also, it has been suggested that they have beneficial effects on serum lipid and oxidative stress status, but the available data are limited and mostly gained from animal models. In this study we evaluated the effects of propolis and N-acetylcysteine supplementation (PropoMucil®) on lipid status, lipoprotein subclasses distribution and paraoxonase 1 activity in subjects with acute respiratory infection.MethodsTwenty subjects with acute respiratory infection were included. PropoMucil® granules for oral solution (80 mg of dry propolis extract and 200 mg of N-acetylcysteine) were administered tree times per day for ten days. Serum lipid profile, paraoxonase 1 activity and low-density and high-density lipoprotein size and subclasses distribution were assessed at baseline and after supplementation.ResultsFollowing ten days of supplementation lipid status remained unchanged, but a significant increase of low-density lipoprotein particle size and proportion of high-density lipoprotein 3a particles were found (P<0.05). Moreover, supplementation with PropoMucil® significantly improved high-density lipoprotein particles distribution, particularly in those who smoke. There was a moderate increase of paraoxonase 1 activity, but without statistical significance.ConclusionsThe presented study demonstrated that short-term supplementation with PropoMucil® has beneficial effects on low-density and high-density lipoprotein subclasses distribution and paraoxonase 1 activity in subjects with acute respiratory infection particularly in those who smoke. 相似文献
823.
We describe how self-reported health (SRH) varies with gender and John Henryism (a strong behavioral predisposition to engage in high-effort coping to overcome adversity) in a low income sample of Serbian Roma. Data were collected in 2016 in several Roma settlements around Belgrade, Serbia. The sample consisted of 90 men and 112 women. In addition to John Henryism (JH), measured by a Serbian version of the John Henryism Scale, demographic data and data on SRH and family relationships dynamics were collected. SRH was positively correlated with age and JH, and negatively correlated with a history of chronic disease. Roma males and females differed significantly on JH and a number of other variables. For Roma women, multiple regression analyses revealed that a history of chronic disease, unemployment, age and daily stress level were negatively associated with SRH, while JH, SES and harmonious relationships with one’s family/children were positively associated with SRH. For Roma men, there was no association between JH and SRH, but older age, being on welfare, a diagnosis of hypertension and extended family disputes were associated with poorer SRH. Hence, despite economic disadvantage and social exclusion from mainstream society, some Roma report good health and the ability to cope actively with economic disadvantage and social exclusion. This study adds to the literature on the cross-cultural relevance of JH theory for understanding health variations within socially and economically marginalized populations. 相似文献
824.
Sanja Milovi Ivan Stankovi Dejan Nikoli Jelena Radovi Marina Kolundi Vesna Nikoli Tatjana Stanojkovi Slavica Petovi Tatjana Kundakovi‐Vasovi 《化学与生物多样性》2019,16(10)
Three seaweeds (Halimeda tuna, Codium bursa and Cystoseira barbata) and one seagrass (Cymodocea nodosa) were collected from the Coast of Montenegro, Gulf of Boka Kotorska and their chemical analysis was performed. In seagrass C. nodosa, three phenolic compounds were identified (diosmetin 7‐sulfate, caftaric and coutaric acid). The content of β‐glucan, fatty acids, sterols and micro‐ and macro‐elements were investigated among all samples. The highest content of β‐glucan was detected in C. nodosa seagrass (13.04±0.42 g/100 g). The highest polyunsaturated fatty acids (PUFAs) level was reported in C. barbata, the brown alga (7.157 mg/g), which also had the significant sterol content (fucosterol, 21.76±0.1 μg/g). Green algae, C. bursa and H. tuna, showed the highest level of sterols (β‐sitosterol, 95.21±0.16 μg/g and 73.90±0.08 μg/g, respectively). H. tuna had the highest content of calcium (Ca) in amount of 55125 μg/g. In C. bursa, C. barbata and C. nodosa, the Na/K ratio was low (0.43, 0.46 and 0.69, respectively). 相似文献
825.
Jelena Godrijan Daniela Marić Pfannkuchen Tamara Djakovac Sanja Frka Blaženka Gašparović 《Global Change Biology》2023,29(17):5075-5086
The future of life on Earth depends on how the ocean might change, as it plays an important role in mitigating the effects of global warming. The main role is played by phytoplankton. Not only are phytoplankton the base of the oceans' food web, but they also play an important role in the biological carbon pump (BCP), the process of forming organic matter (OM) and transporting it to the deep sea, representing a sink of atmospheric CO2. Lipids are considered important vectors for carbon sequestration. A change in the phytoplankton community composition as a result of ocean warming is expected to affect the BCP. Many predictions indicate a dominance of small at the expense of large phytoplankton. To gain insight into interplay between the phytoplankton community structure, lipid production and degradation, and adverse environmental conditions, we analyzed phytoplankton composition, particulate organic carbon (POC) and its lipid fraction in the northern Adriatic over a period from winter to summer at seven stations with a gradient of trophic conditions. We found that at high salinity and low nutrient content, where nanophytoplankton prevailed over diatoms, the newly fixed carbon is substantially directed toward the synthesis of lipids. Lipids produced by nanophytoplankton, coccolithophores, and phytoflagellates, are more resistant to degradation than those produced by diatoms. The difference in lipid degradability is discussed as a difference in the size of the cell phycosphere. We hypothesize that the lipids of nanophytoplankton are less degradable due to the small phycosphere with a poorer bacterial community and consequently a lower lipid degradation rate compared with diatoms. The lipid chemical composition of the different phytoplankton groups could have a different susceptibility to degradation. Results suggest a successful lipid carbon sink of nanophytoplankton and, thus, a negative feedback on global warming. 相似文献
826.
We report the fabrication of a 3D-printed water-heated cuvette that fits into a standard UV visible spectrophotometer. Full 3D-printable designs are provided and 3D-printing conditions have been optimised to provide options to print the cuvette in either acrylonitrile butadiene styrene or polylactic acid polymers, extending the range of solvents that are compatible with the design. We demonstrate the efficacy of the cuvette by determining the critical micelle concentration of sodium dodecyl sulphate at 40 °C, the molar extinction coefficients of cobalt nitrate and dsDNA and by reproducing the thermochromic UV visible spectrum of a mixture of cobalt chloride, water and propan-2-ol. 相似文献
827.
Svetlana Marković Jelena Đurđević Svetlana Jeremić Ivan Gutman 《Journal of molecular modeling》2011,17(4):805-810
Three fluoranthenes and one substituted fluoranthene, 2,2-dimethyl-2H-dibenzo[cd,k]fluoranthene, were investigated using the unrestricted symmetry-broken and complete active space methods. It was shown that
four Kekuléan hydrocarbons are diradicals, implying that their ground state is a triplet. In the energetically less favorable
singlet state these hydrocarbons exhibit pronounced diradical character. This occurance is explained with the tendency of
the investigated molecules to delocalize their π-electrons. This leads to aromatic stabilization which is stronger than destabilization
due to unpaired electrons. Our results for 2,2-dimethyl-2H-dibenzo[cd,k]fluoranthene are in excellent accord with experimental findings of McMaster et al. concerning this compound. 相似文献
828.
Biljana Stojković Darka Šešlija Jovanović Jelena Perovanović Nikola Tucić 《Ethology : formerly Zeitschrift fur Tierpsychologie》2011,117(9):812-821
We evaluated the degree of reproductive isolation between laboratory populations of the seed beetle (Acanthoscelides obtectus) selected to reproduce early (E) or late (L) in life, where different levels of sexual activity and sexual discrimination have been detected. We found a significant level of behavioral isolation among populations within the E selection regime in which beetles showed enhanced early‐life fitness traits and low sexual activity. In contrast, substantially higher levels of sexual activity and an indiscriminate mating system inhibited rather than promoted pre‐zygotic isolation between the L populations. Our results indicate that the study of sexual activity levels may be crucial for understanding the first steps in the pre‐zygotic isolation among allopatric populations subjected to uniform selection. 相似文献
829.
Jelena Postic Jasenka Cosic Karolina Vrandecic Drazenka Jurkovic Amgad A. Saleh John F. Leslie 《Journal of Phytopathology》2012,160(2):76-81
Weeds are alternative hosts of plant pathogens and when colonized may not exhibit disease symptoms. In 2008 and 2009, samples of weeds and plant debris were collected from 12 locations in eastern Croatia, and 300 Fusarium isolates colonizing them were identified. Strains were grouped and identified based on morphology and amplified fragment length polymorphism (AFLP) patterns. Portions of the β‐tubulin and translocation elongation factor 1‐α genes were sequenced from representative strains of each group to confirm the identifications. Fourteen Fusarium species were identified with F. graminearum (20%), F. verticillioides (18%), F. oxysporum (16%), F. subglutinans (13%) and F. proliferatum (11%) all present as more than 10% of the population. Fusarium acuminatum, F. avenaceum, F. concolor, F. crookwellense (F. cerealis), F. equiseti, F. semitectum, F. solani, F. sporotrichioides and F. venenatum, were all present at frequencies < 8%. Our results indicate that economically important Fusarium spp. may be isolated from numerous alternative hosts during the off season and that weeds and plant debris can serve as a reservoir of genetically diverse inoculum. 相似文献