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991.
Resting seeds of several plant species, including barley grains, have been reported to contain aspartic proteinase (EC 3.4.23) activity. Here, the expression of the Hordeum vulgare L. aspartic proteinase (HvAP) was studied in developing and germinating grains by activity measurements as well as by immunocytochemical and in-situ hybridization techniques. Southern blotting suggests the presence of one to two HvAP-encoding genes in the barley genome, while Northern analysis reveals a single 2.1-kb mRNA in grains and vegetative tissues. Western blotting with antibodies to HvAP shows the same subunit structure in different grain parts. In developing grains, HvAP is produced in the embryo, aleurone layer, testa and pericarp, but in the starchy endosperm HvAP is present only in the crushed and depleted area adjacent to the scutellum. During seed maturation, HvAP-encoding mRNA remains in the aleurone layer and in the embryo, but the enzyme disappears from the aleurone cells. The enzyme, however, remains in the degenerating tissues of the testa and pericarp as well as in resting embryo and scutellum. During the first three days of germination, the enzyme reappears in the aleurone layer cells but is not secreted into the starchy endosperm. The HvAP is also expressed in the flowers, stem, leaves, and roots of barley. The wide localization of HvAP in diverse tissues suggests that it may have several functions appropriate to the needs of different tissues.Abbreviations DAA days after anthesis - DTT dithiothreitol - HvAP Hordeum vulgare aspartic proteinase Both authors have contributed equally to this workWe thank Mart Saarma, Pia Runeberg-Roos, Alan Schulman and Yrjö Helariutta for helpful discussions during the study, Tiina Arna and Sari Makkonen for their help in proteinase activity experiments as well as Jaana Korhonen (Department of Pathology, University of Helsinki), Salla Marttila and Ilkka Porali (Department of Biology, University of Jyväskylä, Jyväskylä, Finland) for their advice on microscopical techniques. We also thank Liisa Pyhälä and Leena Liesirova for the production of the antibodies to HvAP at the National Public Health Institute, Helsinki. This study was supported by grants from the Ministry of Agriculture and Forestry and the Academy of Finland.  相似文献   
992.
1. We aimed to demonstrate reproducible nutrition and growth of macrophytes in non‐axenic laboratory cultures preventing growth of phytoplankton and epiphytes. 2. Macrophyte shoot segments were planted in a mixture of commercial acid‐washed silica sand with crystalline tricalcium phosphate, and this artificial sediment was covered with a layer of pure silica sand. The liquid mineral media used did not contain phosphorus but were rich in all other nutrient elements. A CO2 reservoir provided sustainable CO2 supply to macrophyte cultures by gas diffusion through a polyethylene membrane. 3. Chara hispida, Chara tomentosa, Chara baltica, Elodea canadensis, Potamogeton pectinatus and Zanichellia palustris could be cultivated for long term without medium exchange and aeration. Microalgae growth was prevented by the absence of phosphate in the water column. Mobilisation of tricalcium phosphate and phosphate uptake by the rhizoids of C. hispida enabled sustainable rapid shoot growth and increased the concentration of inorganic phosphate in the shoot dry weight by five to six times in comparison with plants cultivated on pure silica sand. A significant growth support from tricalcium phosphate was also observed for E. canadensis, but the rate of phosphate uptake by the roots was not sufficient to maintain a storage pool of inorganic phosphate (Pi) in the growing shoots of this plant. 4. Membrane‐controlled CO2 supply from a reservoir and artificial sediments like the one described provide attractive options for the laboratory culture of macrophytes.  相似文献   
993.
The historical use of Scots Pine (Pinus sylvestris L.) inner bark by the Saami near Lake Sädvajaure, N. Sweden was studied with dendro-ecological methods. Damming of the lake for hydroelectric power enabled destructive sampling of all pines with scars from bark peeling in an area of 870 ha. A total of 111 dead and live pines with 136 bark peelings were found. Stem-sections were taken for cross-dating to determine the precise peeling year and season. The oldest peeling was dated to 1618, which is the oldest reported evidence of Saami use of inner bark. No bark peelings were made after 1870 in the studied area which coincides with a shift to more extensive reindeer herding, and with colonization by Swedish farmers in the area. The regular use of inner bark over time and the absence of peeling peaks in known agrarian famine years support the hypothesis that inner bark was used regularly, and not only as an emergency food. Changes in spatial peeling activity around the lake is interpreted as temporal changes in nomadic fishing activity. We conclude that tree ring studies can provide valuable information about former mobile use of natural resources by Saami in boreal forest landscapes.  相似文献   
994.
In this study, eighteen new isoxazolo[4,5-d]pyridazin-4(5H)-one derivatives possessing either a 1,3,4-thiadiazole or a 1,2,4-triazole-5-thione moiety were synthesized and tested for anti-inflammatory activity in vitro (COX-1/COX-2, 5-LOX) and in vivo (rat paw edema assay). Compounds 15, 16, 25, 26 and 28-30 showed dual COX-2 (IC(50)'s in the 2.1-10.9 μM range), and 5-LOX (IC(50)'s in the 6.3-63.5 μM range) inhibitory activity. When administered orally to rats, dual COX-2/5-LOX inhibitors showed higher anti-inflammatory activity in vivo (30-45% reduction of the inflammatory response) than the reference drug ibuprofen (18%). Among dual COX-2/5-LOX inhibitors, the most potent compound (28) exhibited the best anti-inflammatory profile by inhibiting both COX-2 (IC(50)=2.1 μM) and 5-LOX (IC(50)=6.3 μM) enzymes. We investigated the binding interactions of compound 28 by an enzyme-ligand molecular modeling (docking) studies, which showed favorable binding interactions in both COX-2 and 5-LOX active sites. Furthermore, the dual acting COX-2/5-LOX compound 28 exhibited a superior gastrointestinal safety profile (ulcer index=0.25) compared to the reference drug ibuprofen (UI=7.0) when administered orally at the same molar dose. These observations suggest that isoxazolo[4,5-d]pyridazin-4(5H)-one analogs represent a new scaffold to design potent, effective, and safe anti-inflammatory agents possessing dual COX-2/5-LOX inhibitory activity.  相似文献   
995.
The isolated cathepsin D-like enzyme from Atlantic cod (Gadus morhua L.) liver was shown to be a monomer with a molecular mass of approximately 40 kDa. It was inhibited by Pepstatin A and had an optimum for degradation of haemoglobin at pH 3.0. The purified enzyme had lower temperature stability than bovine cathepsin D. Antibodies raised against the purified enzyme and against two C-terminal peptides of cod cathepsin D recognized a 40 kDa protein in immunoblotting of the samples from the purification process. Both antisera showed cross reactivity with a similar sized protein in liver from cod, saithe (Pollachius virens L.), Atlantic herring (Clupea harengus L.) and Atlantic salmon (Salmo salar L.). A protein of same size was detected in wolffish (Anarhichas lupus L.) liver with the antibody directed against the purified enzyme. This antibody also recognized the native enzyme and detected the presence of cathepsin D in muscle of cod, saithe, herring and salmon. These antibodies may be useful in understanding the mechanisms of post mortem muscle degradation in fish by comparing immunohistochemical localization and enzyme activity, in particular in cod with different rate of muscle degradation. They may also be used for comparing muscle degradation in different fish species.  相似文献   
996.
Owing to their role as vectors of malaria parasites, species of the Anopheles maculipennis complex (Diptera: Culicidae) Meigen were intensively studied in the past, but with the disappearance of malaria in Germany in the middle of the last century, the interest in this field of research declined. A comprehensive ecological analysis of the current species distribution for Germany is lacking. Between 2010 and 2013, a total of 1445 mosquitoes of the An. maculipennis complex were collected at 72 different sites in Germany. The samples comprise 722 single individuals as well as 723 individuals in 90 pools of up to 25 mosquitoes. All samples were analysed with newly developed species‐specific qPCR assays for the identification of the four German species using nucleotide differences within the internal transcribed spacer 2 (ITS2) ribosomal DNA. All gathered data were used for species distribution modelling. The overall prevalence of An. messeae s.l. was highest with 98.89% of all pools; An. daciae with 6.93% of all individuals and An. messeae s.s. with 69.53%. The prevalence of the other two species was relatively low: An. maculipennis s.s. with 13.30% of all individuals (6.67% of all pools) and An. atroparvus with 1.80% of all individuals (1.11% of all pools).  相似文献   
997.
Despite being popular among amateur and professional lepidopterologists and posing great opportunities for evolutionary research, the phylogenetic relationships of tiger moths (Erebidae: Arctiinae) are not well resolved. Here we provide the first phylogenetic hypothesis for the subtribe Arctiina with the basic aim of clarifying the phylogenetic position of the Wood Tiger Moth Parasemia plantaginis Hübner, a model species in evolutionary ecology. We sampled 89 species in 52 genera within Arctiina s.l., 11 species of Callimorphina and two outgroup species. We sequenced up to seven nuclear genes (CAD, GAPDH, IDH, MDH, Ef1α, RpS5, Wingless) and one mitochondrial gene (COI) including the barcode region (a total of 5915 bp). Both maximum likelihood and Bayesian inference resulted in a well‐resolved phylogenetic hypothesis, consisting of four clades within Arctiina s.s. and a clade comprising spilosomine species in addition to Callimorphina and outgroups. Based on our results, we present a new classification, where we consider the Diacrisia clade, Chelis clade, Apantesis clade, Micrarctia Seitz and Arctia clade as valid genera within Arctiina s.s., whereas Rhyparia Hübner syn.n. and Rhyparioides Butler syn.n. are synonymized with Diacrisia Hübner; Neoarctia Neumoegen & Dyar syn.n. , Tancrea Püngeler syn.n. , Hyperborea Grum‐Grshimailo syn.n. , Palearctia Ferguson syn.n. , Holoarctia Ferguson syn.n. , Sibirarctia Dubatolov syn.n. and Centrarctia Dubatolov syn.n. are synonymized with Chelis Rambur; Grammia Rambur syn.n. , Orodemnias Wallengren syn.n. , Mimarctia Neumoegen & Dyar syn.n. , Notarctia Smith syn.n. and Holarctia Smith syn.n. are synonymized with Apantesis Walker; and Epicallia Hübner syn.n. , Eucharia Hübner syn.n. , Hyphoraia Hübner syn.n. , Parasemia Hübner syn.n. , Pericallia Hübner syn.n. , Nemeophila Stephens syn.n. , Ammobiota Wallengren syn.n. , Platarctia Packard syn.n. , Chionophila Guenée syn.n. , Eupsychoma Grote syn.n. , Gonerda Moore syn.n. , Platyprepia Dyar syn.n. , Preparctia Hampson syn.n. , Oroncus Seitz syn.n. , Acerbia Sotavalta syn.n. , Pararctia Sotavalta syn.n. , Borearctia Dubatolov syn.n. , Sinoarctia Dubatolov syn.n. and Atlantarctia Dubatolov syn.n. are synonymized with Arctia Schrank, leading to 33 new genus‐level synonymies. Our focal species Arctia plantaginis comb.n. is placed as sister to Arctia festiva comb.n. , another widespread aposematic species showing wing pattern variation. Our molecular hypothesis can be used as a basis when adding more species to the tree and tackling interesting evolutionary questions, such as the evolution of warning signalling and mimicry in tiger moths.  相似文献   
998.
Abstract

A replacement name, Clarkeophlebia is proposed for the genus name Acanthophlebia Clarke, 1986 in the family Cosmopterigidae (Lepidoptera).  相似文献   
999.
We present a first account of the species of the subfamily Mesochorinae (Hymenoptera: Ichneumonidae) found in Turkey and give distributional records for 5 genera and 23 species. Among them, 3 genera (Cidaphus Förster, 1869; Mesochorella Szepligeti, 1911; Stictopisthus Thomson, 1886) and 20 species are new for the fauna of Turkey.  相似文献   
1000.

This paper provides an account of the potential roles that artifacts can occupy and distinguishes their occurrence as instruments of representation from other types of relationship of artifact use. When artifacts are employed as instruments of representation there is a deliberately constructed causal connection between the artifact and what it represents. This is in contrast to relationships of association in which the artifact takes on features of the context of its occurrence. Anthropological studies of artifact use in the native societies of Africa, America, the Indian Subcontinent and the Pacific are reviewed by comparing “dominant functions” that artifacts can serve.  相似文献   
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