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141.
Ma?gorzata?Klimko Renata?NowińskaEmail authorView authors OrcID profile Paul?Wilkin Justyna?Wiland-Szymańska 《Plant Systematics and Evolution》2018,304(8):1041-1055
Micromorphological features of the leaf epidermis and the inner structure of leaf tissues of eight arborescent taxa of the genus Dracaena were analysed using light and scanning electron microscopy. The plants are xeromorphic or mesomorphic. Their leaves are isobilateral and amphistomatic, and the stomata are anomocytic and tetracytic. The mesophyll in all the species is divided into an outer chlorenchyma and a central region with colourless water-storage cells, chlorophyll cells and vascular bundles. Water-storage cells have wall bands and reticulate thickenings on the walls. The article describes and illustrates several new quantitative and qualitative leaf characters of the dragon tree group. Our findings can be used to identify the dragon tree group leaves, while the shape of epidermal cells and stomata types may be useful in the identification and classification of fragments of fossil leaves. We conclude that D. ombet and D. schizantha are not two distinct species, but should be treated as subspecies of D. ombet. Leaf characters, especially stomata depth on adaxial epidermis, height of adaxial epidermal cells and the presence and thickness of hypodermal fibre bundles markedly differ between geographical groups: Macaronesian species (D. draco and D. tamaranae), the species found in East Africa and Arabian Peninsula (D. ombet subsp. ombet, D. ombet subsp. schizantha, D. serrulata and D. cinnabari) and Southeast Asian species (D. kaweesakii and D. jayniana). 相似文献
142.
Justyna Góraj-Koniarska Marian Saniewski Junichi Ueda Kensuke Miyamoto 《Acta Physiologiae Plantarum》2018,40(2):30
This study aimed to know the key chemical compound influencing gummosis in petioles of intact growing culinary rhubarb (Rheum rhabarbarum L.) with special emphasis on its sugar composition. The application of methyl jasmonate (JA-Me, 0.5 and 1% in lanolin, w/w) in the middle of intact petiole of growing rhubarb substantially induced gummosis in the entire petioles, below and above the treatment, within several days. JA-Me at 0.5% in lanolin greatly stimulated ethylene production in intact petiole of growing rhubarb, on the 3rd day after JA-Me treatment, ethylene level being increased five times or more. However, an ethylene-releasing compound, ethephon (2-chloroethylphosphonic acid, 1 and 2% in lanolin, w/w) alone had no effect on gummosis. Analysis of gum polysaccharides by a gel permeation chromatography with a Tosho TSK-gel G5000PW gel permeation column revealed that almost all of rhubarb gum polysaccharides were eluted near the void in this gel chromatography system, suggesting that molecular mass of rhubarb gum polysaccharides are more than 500 kDa, while precise mass has not been decided in this study. Analysis of gum sugar composition after hydrolysis revealed that rhubarb gums is rich in galactose (ca. 30%), arabinose (ca. 20%), and galacturonic acid (15–20%), although other sugars also existed in small quantities. These results suggest that the key chemical compound of gummosis in petioles of rhubarb is jasmonates rather than ethylene, and gum polysaccharides consist of not only pectic arabinogalactans but also homogalacturonans. 相似文献
143.
Adam Walker Chun-Wa Chung Margarete Neu Manish Burman Thil Batuwangala Gavin Jones Chi-Man Tang Michael Steward Michael Mullin Nadia Tournier Alan Lewis Justyna Korczynska Vicky Chung Ian Catchpole 《The Journal of biological chemistry》2016,291(11):5500-5511
A potent VEGF inhibitor with novel antibody architecture and antigen binding mode has been developed. The molecule, hereafter referred to as VEGF dual dAb (domain antibody), was evaluated in vitro for binding to VEGF and for potency in VEGF-driven models and compared with other anti-VEGF biologics that have been used in ocular anti-angiogenic therapeutic regimes. VEGF dual dAb is more potent than bevacizumab and ranibizumab for VEGF binding, inhibition of VEGF receptor binding assays (RBAs), and VEGF-driven in vitro models of angiogenesis and displays comparable inhibition to aflibercept (Eylea). VEGF dual dAb is dimeric, and each monomer contains two distinct anti-VEGF domain antibodies attached via linkers to a human IgG1 Fc domain. Mechanistically, the enhanced in vitro potency of VEGF dual dAb, in comparison to other anti-VEGF biologics, can be explained by increased binding stoichiometry. A consistent model of the target engagement has been built based on the x-ray complexes of each of the two isolated domain antibodies with the VEGF antigen. 相似文献
144.
Anna Żółciak Katarzyna Sikora Justyna Anna Nowakowska Monika Małecka Małgorzata Borys Anna Tereba 《Biocontrol Science and Technology》2016,26(12):1706-1718
Polymerase chain reaction-amplified and sequenced isolates of Antrodia gossypium, Phlebiopsis gigantea and Heterobasidion parviporum from decaying Norway spruce wood blocks after three and six months, which exhibited linear growth, were investigated. P. gigantea strains showed the fastest growth, whereas A. gossypium growth was five times slower. The differences between the mean daily increment of A. gossypium and the other examined isolates (except Hp2) were statistically significant. There were also significant differences in wood decay between densities over time. These results were confirmed by the decay acceleration index (DAI) and decay activity index, which were positively correlated with wood density regardless of the fungus species. The registered P. gigantea strains (Rotstop and PG Suspension) exhibited a strong decomposition ability (28% after six months); the weight loss caused by A. gossypium after six months of decay (15.2%) was similar to the results of P. gigantea (GB) after just three months (13.2%). All tested H. parviporum isolates showed rather rapid growth and equally strong wood decay (20–25%) compared to those of P. gigantea. DAI showed that A. gossypium may significantly contribute to wood decomposition over time, particularly in less dense wood samples. The use of both saprotrophs as biological agents against root pathogens is discussed. 相似文献
145.
Małgorzata Pleszczyńska Adrian Wiater Marek Siwulski Marta K. Lemieszek Justyna Kunaszewska Józef Kaczor Wojciech Rzeski Grzegorz Janusz Janusz Szczodrak 《World journal of microbiology & biotechnology》2016,32(9):151
Piptoporus betulinus is a wood-rotting basidiomycete used in medicine and biotechnology. However, to date, no indoor method for cultivation of this mushroom fruiting bodies has been developed. Here we present the first report of successful production of P. betulinus mature fruiting bodies in artificial conditions. Four P. betulinus strains were isolated from natural habitats and their mycelia were inoculated into birch sawdust substrate supplemented with organic additives. All the strains effectively colonized the medium but only one of them produced fruiting bodies. Moisture and organic supplementation of the substrate significantly determined the fruiting process. The biological efficiency of the P. betulinus PB01 strain cultivated on optimal substrate (moisture and organic substance content of 55 and 65 and 25 or 35 %, respectively) ranged from 12 to 16 %. The mature fruiting bodies reached weight in the range from 50 to 120 g. Anticancer properties of water and ethanol extracts isolated from both cultured and nature-derived fruiting bodies of P. betulinus were examined in human colon adenocarcinoma, human lung carcinoma and human breast cancer cell lines. The studies revealed antiproliferative and antimigrative properties of all the investigated extracts. Nevertheless the most pronounced effects demonstrated the ethanol extracts, obtained from fruiting bodies of cultured P. betulinus. Summarizing, our studies proved that P. betulinus can be induced to fruit in indoor artificial culture and the cultured fruiting bodies can be used as a source of potential anticancer agents. In this respect, they are at least as valuable as those sourced from nature. 相似文献
146.
147.
Emotional intelligence (EI) and morningness–eveningness (M-E) preference have been shown to influence mood states. The present article investigates the way in which these two constructs may interact, influencing morning and evening mood levels. A sample of 172 participants completed a multidimensional mood scale measuring energetic arousal (EA), tense arousal (TA), and hedonic tone at 7:00 and at 22:00. As expected, morning and evening types experienced higher EA at their preferred time of day; effects of M-E on other mood dimensions were weaker. EI was found to correlate with lower TA, but the association was stronger at 22:00, perhaps reflecting the role of EI in managing the social events characteristic for the evening hours. An interactive effect of EI and M-E was found for both diurnal changes and morning levels of EA. Namely, in individuals higher in EI, there appeared a more marked synchrony effect between chronotype and EA, which was absent in those low in EI; individuals higher in EI showed more pronounced diurnal changes in EA characteristic for their chronotype (i.e., higher EA at morning hours in morning chronotypes; higher EA at evening hours in evening chronotypes), while in participants low in EI, diurnal changes in EA were smaller. Moreover, the characteristic positive association between morningness and EA during morning hours was apparent only in those high in EI. These findings suggest that individual differences in circadian variation in mood reflect several factors, including an endogenous rhythm in energy, the distribution of social activities throughout the day, and the person’s awareness of their own energy level. 相似文献
148.
Joanna Pokorska Dominika Kułaj Magdalena Dusza Justyna Żychlińska-Buczek Joanna Makulska 《Animal biotechnology》2016,27(2):113-117
Isolation of genomic DNA is one of the basic steps in many different molecular analyses. There are a few reports on methods of DNA isolation from milk, but many of them are time consuming and expensive, and require relatively large volumes of raw milk. In this study a rapid, sensitive, and efficient method of DNA extraction from milk somatic cells of various mammals (cattle, sheep, goats, horses) is presented. It was found that milk is a good source of genomic DNA, and to obtain a sufficient amount and quality of DNA, suitable for molecular analysis such as PCR, 10 mL of raw milk is sufficient. Thanks to this method, stress in animals can be reduced during collection of researched material. Therefore, this method could be widely used in molecular analyses. 相似文献
149.
Joanna Pieńkowska Katarzyna Gwo?dziewicz Katarzyna Skrobisz-Balandowska Iwona Marek Justyna Kostro Edyta Szurowska Micha? Studniarek 《PloS one》2016,11(1)
Purpose
Severe acute pancreatitis (AP) is still a significant clinical problem which is associated with a highly mortality. The aim of this study was the evaluation of prognostic value of CT regional perfusion measurement performed on the first day of onset of symptoms of AP, in assessing the risk of developing severe form of acute pancreatitis.Material and Methods
79 patients with clinical symptoms and biochemical criteria indicative of acute pancreatitis (acute upper abdominal pain, elevated levels of serum amylase and lipase) underwent perfusion CT within 24 hours after onset of symptoms. The follow-up examinations were performed after 4–6 days to detect progression of the disease. Perfusion parameters were compared in 41 people who developed severe form of AP (pancreatic and/or peripancreatic tissue necrosis) with parameters in 38 consecutive patients in whom course of AP was mild. Blood flow, blood volume, mean transit time and permeability surface area product were calculated in the three anatomic pancreatic subdivisions (head, body and tail). At the same time the patient''s clinical status was assessed by APACHE II score and laboratory parameters such as CRP, serum lipase and amylase, AST, ALT, GGT, ALP and bilirubin were compared.Results
Statistical differences in the perfusion parameters between the group of patients with mild and severe AP were shown. Blood flow, blood volume and mean transit time were significantly lower and permeability surface area product was significantly higher in patients who develop severe acute pancreatitis and presence of pancreatic and/or peripancreatic necrosis due to pancreatic ischemia. There were no statistically significant differences between the two groups in terms of evaluated on admission severity of pancreatitis assessed using APACHE II score and laboratory tests.Conclusions
CT perfusion is a very useful indicator for prediction and selection patients in early stages of acute pancreatitis who are at risk of developing pancreatic and/or peripancreatic necrosis already on the first day of the onset of symptoms and can be used for treatment planning and monitoring of therapy of acute pancreatitis. Early suspicion of possible pancreatic necrosis both on the basis of scores based on clinical status and laboratory tests have low predictive value. 相似文献150.