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331.
MILKA VRECL LUKA DRINOVEC CHRISTIAN ELLING ANDERS HEDING 《Journal of receptor and signal transduction research》2013,33(5-6):505-526
Using bioluminescence resonance energy transfer (BRET) we studied opsin oligomerization in heterologous expression systems and quantitatively assessed its oligomerization state. BRET2 saturation and competition experiments were performed with live COS-7 cells expressing Rluc-and GFP2-tagged receptor constructs. BRET2 saturation curves obtained were hyperbolic, and the calculated oligomerization state (N = 1 for dimers) suggested that opsin (N = 1.34 ± 0.25) forms higher oligomers. Very high BRET2 values obtained for the opsin homo-dimer pair indicated a large energy transfer efficiency (E) and for cases where E ? 0.1 a modified saturation curve was proposed. The existence of homo-dimer complexes was additionally supported by competition assay results and was also observed in HEK-293 cells. Furthermore, evidence was provided for homo-and hetero-dimerization of family A (β2-adrenergic) and B (gastric inhibitory polypeptide, GIP) receptors. In summary, these experiments demonstrate homo-and hetero-dimerization for opsin, β 2-adrenergic, and GIP receptors. 相似文献
332.
Effects of ski piste preparation on alpine vegetation 总被引:4,自引:0,他引:4
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Abstract. The nominal taxon Acanthosoma chrysalis Mayer, 1844 is revised, and a lectotype is designated. The species, which was described from Germany from a number of alleged parasites encysted in the peritoneal wall of the stomach of edible frogs, is shown to be based on first instar larvae of blow flies (Calliphoridae). Argued from the shape and configuration of mouthhooks and abdominal cuticular spines, Acanthosoma Mayer, 1844 is shown to be a junior synonym of Onesia Robineau-Desvoidy, 1830 , syn.n. , and A. chrysalis is shown to be a junior synonym of O. floralis Robineau-Desvoidy, 1830 , syn.n. This species is an obligate parasitoid of earthworms, and it is hypothesized that first instar larvae enter the frogs through infected earthworms. 相似文献
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336.
WOLFGANG ARTHOFER† MARKUS RIEGLER‡ DANIELA SCHNEIDER§ MARTIN KRAMMER§ WOLFGANG J. MILLER§ CHRISTIAN STAUFFER 《Molecular ecology》2009,18(18):3816-3830
The European cherry fruit fly Rhagoletis cerasi has been a field model for cytoplasmic incompatibility since the mid 1970s. Two Wolbachia strains were detected in this tephritid species and w Cer2 was described as the CI inducing agent dividing European populations into two unidirectional incompatible groups, i.e. southern females produce viable offspring with northern males, whereas the reciprocal cross results in incompatibility. We detected three new Wolbachia strains by sequencing a multitude of plasmids derived from Wolbachia surface protein gene ( wsp ) polymerase chain reaction (PCR) products. Strain-specific primers were developed allowing individual diagnosis without need for cloning. Hybridization of specific PCR products with a wsp oligonucleotide enhanced the detection limit significantly and revealed the presence of low-titre infections in some strains, in different ontogenetic stages and in adults of different age. We then performed a survey of strain prevalence and infection frequency in eight European regions. w Cer1 was fixed in all populations, whereas w Cer2 was detected only in the South. w Cer3 frequency was the lowest without a clear distribution pattern. The abundance of w Cer4 was homogenous across Europe. Like w Cer2, w Cer5 showed significant differences in spatial distribution. Our new findings of previously undetected and recombinant Wolbachia strains in R. cerasi reveal a major caveat to the research community not to overlook hidden Wolbachia diversity in field populations. Low-titres and geographical variability in Wolbachia diversity are expected to influence the outcome of Wolbachia population dynamics and Wolbachia- based insect population control and may create invasion barriers for expanding and artificially introduced Wolbachia strains. 相似文献
337.
The flower fly genus Eosalpingogaster Hull, predator of the carminic acid producer cochineal (Dactylopiidae), is revised. Two new species are described (knutsoni sp.n. and umbra sp.n. ) and an identification key is provided for all known species. Diagnoses, illustrations, synonymies and distributional and biological data are given. Three new synonyms are proposed [texana Curran as jun.syn. of cochenillivora (Guérin‐Méneville); liposeta Fluke and dactylopianus Blanchard as jun.syn. of nigriventris (Bigot)] and two lectotypes are designated for cochenillivora (Guérin‐Méneville) and nigriventris (Bigot). Eosalpingogaster is elevated to full generic status based on adult morphological characters, biological data and a new phylogenetic analysis of molecular characters with genes 28S, 18S and cytochrome c oxidase subunit I. All data, images and drawings are available online as an example of the utility of international standards for biodiversity informatics. 相似文献
338.
This paper analyses ethical issues in forensic psychiatric research on mentally disordered offenders, especially those detained in the psychiatric treatment system. The idea of a 'dual role' dilemma afflicting forensic psychiatry is more complicated than acknowledged. Our suggestion acknowledges the good of criminal law and crime prevention as a part that should be balanced against familiar research ethical considerations. Research aiming at improvements of criminal justice and treatment is a societal priority, and the total benefit of studies has to be balanced against the risks for research subjects inferred by almost all systematic studies. Direct substantial risks must be balanced by health benefits, and normal informed consent requirements apply. When direct risks are slight, as in register-based epidemiology, lack of consent may be counter-balanced by special measures to protect integrity and the general benefit of better understanding of susceptibility, treatment and prevention. Special requirements on consent procedures in the forensic psychiatric context are suggested, and the issue of the relation between decision competence and legal accountability is found to be in need of further study. The major ethical hazard in forensic psychiatric research connects to the role of researchers as assessors and consultants in a society entertaining strong prejudices against mentally disordered offenders. 相似文献
339.
Chemotherapy through Lysosomes with a DNA-Daunorubicin Complex 总被引:7,自引:0,他引:7
ANDRÉ TROUET DANIELÈ DEPREZ-DE CAMPENEERE CHRISTIAN DE DUVE 《Nature: New biology》1972,239(91):110-112
WHEN a drug can pass freely across cell membranes, it becomes distributed throughout the body fluids whichever its route of administration and invades all cells by diffusion at comparable rates. But if it is firmly associated with a non-permeant, pino-cytizable and digestible carrier, it will tend to remain confined within a smaller fluid space determined by its route of administration, its excretion will be slow and its intracellular penetration will be restricted to the endocytic route (Fig. 1). Free drug will then appear first within lysosomes, following digestion of the carrier. From the lysosomes it will diffuse into the other parts of the cells and eventually into the extracellular fluids. The intracellular concentration of the drug thus becomes dependent on the pinocytic activity of the cells and on the digestive potential of their lysosomes and must exceed the extracellular concentration in the most active cells. Obviously, this model requires the complex to be stable in the body fluids and to dissociate inside lysosomes. The drug itself must be resistant to lysosomal inactivation. 相似文献
340.
BIBIANE STEINECKER CHRISTIAN ROSKER WOLFGANG SCHREIBMAYER 《Journal of receptor and signal transduction research》2013,33(5-6):369-382
Four isoforms of GIRK channels (GIRK1–4) have been described in humans. In addition, several splice variants of more or less unknown function have been identified from several tissues and species. In our study, we investigated the structure and function of a new variant of GIRK1 that has been isolated from rat brain. Because of wide similarities with a previously described variant, we also named it GIRK1d. This variant lacks a region corresponding to exon 2 of full-length GIRK1, leading to a truncated GIRK1 that lacks the main part of the C-terminus. To study GIRK1d we used the Xenopus laevis expression system, the two-electrode voltage clamp method, and confocal laser scan microscopy. We found that our GIRK1d variant preferentially binds GIRK2 or GIRK4 over GIRK1. Furthermore, it largely reduces conductances mediated by GIRK1/2 or GIRK1/4 hetero-multimeric channels when coexpressed and nearly totally abolishes currents when replacing GIRK1 in hetero-multimeric channels. 相似文献