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201.
Habitat monitoring in Europe: a description of current practices 总被引:1,自引:0,他引:1
Szabolcs Lengyel Eszter Déri Zoltán Varga Roland Horváth Béla Tóthmérész Pierre-Yves Henry Andrej Kobler Lado Kutnar Valerija Babij Andrej Seliškar Chysoula Christia Eva Papastergiadou Bernd Gruber Klaus Henle 《Biodiversity and Conservation》2008,17(14):3327-3339
Monitoring of biodiversity at the level of habitats is becoming increasingly common. Here we describe current practices in
habitat monitoring based on 150 schemes in Europe. Most schemes were initiated after 1990 in response to EU nature directives
or habitat management/restoration actions, with funding mostly from European or national sources. Schemes usually monitor
both the spatial distribution and the quality of the habitats, and they frequently collect data on environmental parameters
and potential causes of changes. Many schemes are local or regional rather than national or international in scope, and sampling
effort varies greatly across spatial and temporal scales. Experimental design is used in half of the schemes, however, data
are rarely analysed by advanced statistics. Most schemes require two months or less per year in manpower and are typically
run by professionals rather than by volunteers. Estimated salaries plus equipment costs average 650,000 Euro per year per
scheme, and add up to 80 million Euros annually. Costs are particularly high for schemes based on European or international
law and for schemes funded by European or national sources. Costs are also high in schemes in which sampling sites are selected
subjectively rather than based on sampling theory, and in schemes that do not use field mapping or remote sensing to document
spatial variation in habitats. Our survey demonstrates promising developments in European habitat monitoring but also underlines
the need for better spatial coverage, documentation of spatial variaton, improved sampling design and advanced data analysis.
Such improvements are essential if we are to judge progress towards the 2010 biodiversity targets. 相似文献
202.
Horváth Z Farkas P Ganofszky E Hitre E Juhos E Nagy T Rubovszky G Szabó E Láng I 《Magyar onkologia》2008,52(1):49-55
Renal function aberrations during bisphosphonate treatment is a well-known phenomenon. In our retrospective study we examined renal functions of 97 breast cancer patients with bone metastasis during their first year of bisphosphonate treatment i.e. (1) frequency of initial renal function alterations; (2) frequency of decreasing renal function during bisphosphonate treatment; (3) the connection between the laboratory findings and the renal function parameters measured at the beginning of bisphosphonate treatment. At the beginning of bisphosphonate treatment we found a surprisingly high rate (26.80%) of decreased creatinine clearance calculated by the Cockcroft-Gault formula. Decreased creatinine clearance at least once during bisphosphonate treatment has been found in 32.99% of the patients, and in 13.4% of the patients with decreased renal function parameters before bisphosphonates it remained decreased during the one-year period. Expected normal renal function is prognosticated by the renal function parameters and serum calcium level measured before starting bisphosphonate treatment. However, we could not demonstrate any connection between decreasing renal function and either the route of administration or the generation or type of bisphosphonates or the previous use of platinum compounds. Our analysis confirms the necessity of monitoring renal function before and during bisphosphonate treatment, and it is advisable to calculate the creatinine clearance in the upper quarter of the normal range of creatinine levels. In case of decreased renal function, change to a less nephrotoxic bisphosphonate or discontinuing the treatment is suggested. While our results are at variance with the published literature, the above-mentioned questions should be examined in a prospective trial. 相似文献
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204.
The conformational properties of a diastereomeric nucleoside-phosphorothioate pair is reported as reflected by different NMR parameters. Configurational assessment is based partly on the different NOE (nuclear overhauser enhancement) effects of the individual isomers and on the trends observed in other NMR parameters. Vicinal carbon-phosphorus couplings reflect the predominance of the epsilon(-) conformation for the Sp isomer and the epsilon(t) conformation for the Rp isomer. The effects of solvent and temperature on these vicinal couplings are described and the results are interpreted in terms of conformational shift towards the preferred epsilon(t) conformation. 相似文献
205.
206.
207.
State-dependent inhibition of cystic fibrosis transmembrane conductance regulator chloride channels by a novel peptide toxin 总被引:1,自引:0,他引:1
Fuller MD Thompson CH Zhang ZR Freeman CS Schay E Szakács G Bakos E Sarkadi B McMaster D French RJ Pohl J Kubanek J McCarty NA 《The Journal of biological chemistry》2007,282(52):37545-37555
Peptide toxins from animal venom have been used for many years for the identification and study of cation-permeable ion channels. However, no peptide toxins have been identified that interact with known anion-selective channels, including cystic fibrosis transmembrane conductance regulator (CFTR), the protein defective in cystic fibrosis and a member of the ABC transporter superfamily. Here, we describe the identification and initial characterization of a novel 3.7-kDa peptide toxin, GaTx1, which is a potent and reversible inhibitor of CFTR, acting from the cytoplasmic side of the membrane. Thus, GaTx1 is the first peptide toxin identified that inhibits a chloride channel of known molecular identity. GaTx1 exhibited high specificity, showing no effect on a panel of nine transport proteins, including Cl(-) and K(+) channels, and ABC transporters. GaTx1-mediated inhibition of CFTR channel activity is strongly state-dependent; both potency and efficacy are reduced under conditions of elevated [ATP], suggesting that GaTx1 may function as a non-competitive inhibitor of ATP-dependent channel gating. This tool will allow the application of new quantitative approaches to study CFTR structure and function, particularly with respect to the conformational changes that underlie transitions between open and closed states. 相似文献
208.
Jaworski K Sarkadi-Nagy E Duncan RE Ahmadian M Sul HS 《American journal of physiology. Gastrointestinal and liver physiology》2007,293(1):G1-G4
Triacylglycerol (TAG) stored in adipose tissue can be rapidly mobilized by the hydrolytic action of lipases, with the release of fatty acids (FA) that are used by other tissues during times of energy deprivation. Unlike synthesis of TAG, which occurs not only in adipose tissue but also in other tissues such as liver for very-low-density lipoprotein formation, hydrolysis of TAG, lipolysis, predominantly occurs in adipose tissue. Until recently, hormone-sensitive lipase was considered to be the key rate-limiting enzyme responsible for regulating TAG mobilization. However, recent studies on hormone-sensitive lipase-null mice have challenged such a concept. A novel lipase named desnutrin/ATGL has been recently discovered to play a key role in lipolysis in adipocytes. Lipolysis is under tight hormonal regulation. Although opposing regulation of lipolysis in adipose tissue by insulin and catecholamines is well understood, autocrine/paracrine factors may also participate in its regulation. Intricate cooperation of these endocrine and autocrine/paracrine factors leads to a fine regulation of lipolysis in adipocytes, needed for energy homeostasis. In this review, we summarize and discuss the recent progress made in the regulation of adipocyte lipolysis. 相似文献
209.
Csordás A Pankotai E Snipes JA Cselenyák A Sárszegi Z Cziráki A Gaszner B Papp L Benko R Kiss L Kovács E Kollai M Szabó C Busija DW Lacza Z 《Life sciences》2007,80(7):633-637
Previous studies raised the possibility that nitric oxide synthase is present in heart mitochondria (mtNOS) and the existence of such an enzyme became generally accepted. However, original experimental evidence is rather scarce and positive identification of the enzyme is lacking. We aimed to detect an NOS protein in human and mouse heart mitochondria and to measure the level of NO released from the organelles. Western blotting with 7 different anti-NOS antibodies failed to detect a NOS-like protein in mitochondria. Immunoprecipitation or substrate-affinity purification of the samples concentrated NOS in control preparations but not in mitochondria. Release of NO from live respiring human mitochondria was below 2 ppb after 45 min of incubation. In a bioassay system, mitochondrial suspension failed to cause vasodilation of human mammary artery segments. These results indicate that mitochondria do not produce physiologically relevant quantities of NO in the heart and are unlikely to have any physiological importance as NO donors, nor do they contain a recognizable mtNOS enzyme. 相似文献
210.
Perle Latr De Lat Malak Haidar Hifzur Ansari Shahin Tajeri Eszter Szarka Anita Alexa Kerry Woods Attila Remnyi Arnab Pain Gordon Langsley 《Cellular microbiology》2019,21(3)
Constitutive c‐Jun N‐terminal kinase (JNK) activity characterizes bovine T and B cells infected with Theileria parva, and B cells and macrophages infected with Theileria annulata. Here, we show that T. annulata infection of macrophages manipulates JNK activation by recruiting JNK2 and not JNK1 to the parasite surface, whereas JNK1 is found predominantly in the host cell nucleus. At the parasite's surface, JNK2 forms a complex with p104, a GPI‐(GlycosylPhosphatidylInositol)‐anchor T. annulata plasma membrane protein. Sequestration of JNK2 depended on Protein Kinase‐A (PKA)‐mediated phosphorylation of a JNK‐binding motif common to T. parva and a cell penetrating peptide harbouring the conserved p104 JNK‐binding motif competitively ablated binding, whereupon liberated JNK2 became ubiquitinated and degraded. Cytosolic sequestration of JNK2 suppressed small mitochondrial ARF‐mediated autophagy, whereas it sustained nuclear JNK1 levels, c‐Jun phosphorylation, and matrigel traversal. Therefore, T. annulata sequestration of JNK2 contributes to both survival and dissemination of Theileria‐transformed macrophages. 相似文献