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991.
Michael Schalli Patrick Weber Christina Tysoe Bettina M. Pabst Martin Thonhofer Eduard Paschke Arnold E. Stütz Marion Tschernutter Werner Windischhofer Stephen G. Withers 《Bioorganic & medicinal chemistry letters》2017,27(15):3431-3435
N-Functionalized amino(hydroxymethyl)cyclopentanetriols are potent inhibitors of β-d-galactosidases and, for the first time, could be shown to act as pharmacological chaperones for GM1-gangliosidosis-associated lysosomal acid β-galactosidase thus representing a new structural type of pharmacological chaperones for this lysosomal storage disease. 相似文献
992.
The bulky and the sweet: How neutralizing antibodies and glycan receptors compete for virus binding 下载免费PDF全文
Christina Harprecht Thilo Stehle 《Protein science : a publication of the Protein Society》2017,26(12):2342-2354
Numerous viruses rely on glycan receptor binding as the initial step in host cell infection. Engagement of specific glycan receptors such as sialylated carbohydrates, glycosaminoglycans, or histo‐blood group antigens can determine host range, tissue tropism, and pathogenicity. Glycan receptor‐binding sites are typically located in exposed regions on viral surfaces—sites that are also generally prone to binding of neutralizing antibodies that directly interfere with virus‐glycan receptor interactions. In this review, we examine the locations and architecture of the glycan‐ and antibody‐binding sites in four different viruses with stalk‐like attachment proteins (reovirus, influenza virus, norovirus, and coronavirus) and investigate the mechanisms by which antibodies block glycan recognition. Those viruses exemplify that direct molecular mimicking of glycan receptors by antibodies is rare and further demonstrate that antibodies often partly overlap or bind sufficiently close to the receptor‐binding region to hinder access to this site, achieving neutralization partially because of the epitope location and partly due to their sheer size. 相似文献
993.
994.
Mate choice screening in captive solitary carnivores: The role of male behavior and cues on mate preference and paternity in females of a model species,American mink (Neovison vison) 下载免费PDF全文
995.
Erica Lana Mahbod Khanbolouki Charline Degavre Eva-Britt Samuelsson Elisabet Åkesson Bengt Winblad Evren Alici Christina Unger Lithner Homira Behbahani 《Molecular neurobiology》2017,54(2):874-887
Studies on the mechanisms of neuronal amyloid-β (Aβ) internalisation are crucial for understanding the neuropathological progression of Alzheimer’s disease (AD). We here investigated how extracellular Aβ peptides are internalised and focused on three different pathways: (i) via endocytic mechanisms, (ii) via the receptor for advanced glycation end products (RAGE) and (iii) via the pore-forming protein perforin. Both Aβ40 and Aβ42 were internalised in retinoic acid differentiated neuroblastoma (RA-SH-SY5Y) cells. A higher concentration was required for Aβ40 (250 nM) compared with Aβ42 (100 nM). The internalised Aβ40 showed a dot-like pattern of distribution whereas Aβ42 accumulated in larger and distinct formations. By confocal microscopy, we showed that Aβ40 and Aβ42 co-localised with mitochondria, endoplasmic reticulum (ER) and lysosomes. Aβ treatment of human primary cortical neurons (hPCN) confirmed our findings in RA-SH-SY5Y cells, but hPCN were less sensitive to Aβ; therefore, a 20 (Aβ40) and 50 (Aβ42) times higher concentration was needed for inducing uptake. The blocking of endocytosis completely inhibited the internalisation of Aβ peptides in RA-SH-SY5Y cells and hPCN, indicating that this is a major pathway by which Aβ enters the cells. In addition, the internalisation of Aβ42, but not Aβ40, was reduced by 55 % by blocking RAGE. Finally, for the first time we showed that pore formation in cell membranes by perforin led to Aβ internalisation in hPCN. Understanding how Aβ is internalised sheds light on the pathological role of Aβ and provides further ideas of inhibitory strategies for preventing Aβ internalisation and the spreading of neurodegeneration in AD. 相似文献
996.
Caroline de Souza Barros Valeria Garrido Vanessa Melchiades Rafaela Gomes Max Willian Lisboa Gomes Valeria Laneuville Teixeira Izabel Christina Nunes de Palmer Paixão 《Journal of applied phycology》2017,29(2):769-773
Studies with diterpenes from marine brown alga Canistrocarpus cervicornis showed the antiviral potential of the products from this alga in controlling the replication of HSV-1 and maintaining low cytotoxicity. Hence, the aim of this work was to evaluate the anti-herpetic efficacy of C. cervicornis extract ointment in BALB/c mice. To test the anti-herpetic efficacy in vivo, four groups of BALB/c mice (n?=?5) were used: 1—untreated, 2—extract ointment (2 % or 0.4 mg cm?2 dose?1), 3—Acyclovir cream (5 % or 1.0 mg cm?2 dose?1), and 4—ointment base. The right midflank of each mouse was clipped and depilated with a chemical depilatory. After 2 days, the skin area was scratched and inoculated with HSV-1. The ointments and cream were applied three times a day over a 16-day period, beginning 1 h after virus inoculation. The development of skin lesions was continuously monitored and scored. To evaluate the effect of C. cervicornis topical treatment on biochemical parameters and on body weight, two uninfected groups were formed: an untreated group and a group treated with ointment C. cervicornis extract (2 %). The signs of infection appeared from the second day after infection, while on the 10th day of the experiment, the ointment base and untreated groups had significantly more severe lesions than did the groups that were treated with extract (p?<?0.05) or acyclovir (p?<?0,01). The topical application of extract ointment did not change body weight, hepatic, or renal function suggesting that the extract has a low toxicity in this route of administration. These results suggest that the extract may be useful in reducing the severity of HSV-1 cutaneous lesions. 相似文献
997.
Carbohydrate uptake in Advenella mimigardefordensis strain DPN7T is mediated by periplasmic sugar oxidation and a TRAP‐transport system 下载免费PDF全文
Christina Meinert Jana Senger Marco Witthohn Jan Hendrik Wübbeler Alexander Steinbüchel 《Molecular microbiology》2017,104(6):916-930
In this study, we investigated an SBP (DctPAm) of a tripartite ATP‐independent periplasmic transport system (TRAP) in Advenella mimigardefordensis strain DPN7T. Deletion of dctPAm as well as of the two transmembrane compounds of the tripartite transporter, dctQ and dctM, impaired growth of A. mimigardefordensis strain DPN7T, if cultivated on mineral salt medium supplemented with d ‐glucose, d ‐galactose, l ‐arabinose, d ‐fucose, d ‐xylose or d ‐gluconic acid, respectively. The wild type phenotype was restored during complementation studies of A. mimigardefordensis ΔdctPAm using the broad host vector pBBR1MCS‐5::dctPAm. Furthermore, an uptake assay with radiolabeled [14C(U)]‐d ‐glucose clearly showed that the deletion of dctPAm, dctQ and dctM, respectively, disabled the uptake of this aldoses in cells of either mutant strain. Determination of KD performing thermal shift assays showed a shift in the melting temperature of DctPAm in the presence of d ‐gluconic acid (KD 11.76 ± 1.3 µM) and the corresponding aldonic acids to the above‐mentioned carbohydrates d ‐galactonate (KD 10.72 ± 1.4 µM), d ‐fuconic acid (KD 13.50 ± 1.6 µM) and d ‐xylonic acid (KD 8.44 ± 1.0 µM). The sugar (glucose) dehydrogenase activity (E.C.1.1.5.2) in the membrane fraction was shown for all relevant sugars, proving oxidation of the molecules in the periplasm, prior to transport. 相似文献
998.
The effects of paternal reproductive tactic and rearing environment on juvenile variation in growth as mediated through aggression and foraging behaviours of Chinook salmon (Oncorhynchus tshawytscha) 下载免费PDF全文
Adriana R. Forest Mitchel G. E. Dender Trevor E. Pitcher Christina A. D. Semeniuk 《Ethology : formerly Zeitschrift fur Tierpsychologie》2017,123(5):329-341
In species with indeterminate growth, differential growth rates can lead to animals adopting alternative reproductive tactics such as sneak–guard phenotypes, which is partially predicted by variation in growth during the juvenile life‐history stage. To investigate sources of growth variation, we examined the independent and joint effects of paternal reproductive tactic (G) and rearing environment (E) on juvenile growth in Chinook salmon (Oncorhynchus tshawytscha), hypothesizing G and E effects are partially mediated through differences in behaviour such as aggressive interactions and resulting foraging behaviours. We created maternal half‐sibling families with one‐half of the female's eggs fertilized by the milt of a sneaker “jack” and the other half by a guarder “hooknose”. At the exogenous feeding stage, each split‐clutch family was then divided again and reared in a rationed diet or growth‐promotion diet environment for approximately 6 months, during which growth parameters were measured. Before saltwater transfer at 9 months of age, social interactions were observed in groups of six fish of various competitor origins. We found ration restricts growth rate and juvenile mass, and evidence of genetic effects on growth depensation, where jack‐sired individuals grew less uniformly over time. These growth‐related differences influenced an individual's level of aggression, with individuals raised on a restricted diet and those whose families experienced greatest growth being most aggressive. These individuals were more likely to feed than not and feed most often. Jack‐sired individuals were additionally aggressive in the absence of food, and when raised on a rationed diet outcompeted others to feed most. These results show how individuals may achieve higher growth rates via intrinsic (G) or induced (E) aggressive behavioural phenotypes, and eventually attain the threshold body size necessary during the saltwater phase to precociously sexually mature and adopt alternative reproductive phenotypes. 相似文献
999.
Fengyong Liu Zhiqiang Meng Guoliang Shao Jianhua Wang Zhijun Wang Jijin Yang Christina S M Yip Dongfeng He 《Molecular biology reports》2017,44(1):149-158
To analyze safety and efficacy of patterns of sorafenib and TACE therapy under real-life clinical practice conditions. A total of 338 Chinese patients with unresectable hepatocellular carcinoma (HCC) from the international database of the GIDEON non-interventional trial were included in this analysis. Endpoints were overall survival (OS), progression-free survival (PFS), time to progression (TTP) and safety. Two major patterns in the use of sorafenib observed in current Chinese clinical practice were: sorafenib administration subsequent to transarterial chemoembolization (TACE) treatment (n?=?226, 66.9%) and sorafenib administration concomitant to TACE (n?=?80, 35.4%). Patients receiving TACE prior to sorafenib had worse liver function (43.8% BCLC stage Cat diagnosis and 62.1% BCLC stage C at study entry) than those receiving TACE concomitant to sorefenib (35.0% BCLC stage C at diagnosis and 51.3% BCLC stage three at study entry). For patients undergoing prior TACE and concomitant TACE treatment, median OS time was 354 days vs. 608 days, PFS time was 168 days vs. 201 days, and TTP was 214 days vs. 205 days; and the percentage of patients who experienced drug-related adverse effects after sorafenib therapy in these two groups were 33.3 and 50.0%, respectively. Sorafenib treatment is usually administered in cases of tumor progression or poor liver function status after TACE treatment in China. Under such conditions, patients still gained a relatively satisfactory survival outcome. In addition, the present study suggests that concomitant sorafenib and TACE treatments may lead to a better prognosis, although differences in baseline characteristics may have contributed in part to the better outcomes. 相似文献
1000.
Christina Campbell Daniel L. Kelly Noeleen Smyth Neil Lockhart David T. Holyoak 《Journal of bryology》2017,39(2):141-151
Ditrichum cornubicum is a rare and threatened acrocarpous moss found on copper-rich mine waste, characteristic of the EU protected habitat ‘Calaminarian grassland of the Violetalia calaminariae’. The species was once thought to be a British endemic, being known from two former copper/tin mine sites in Cornwall, until the discovery of a population in 2006 at Allihies Mountain Mine, Co. Cork, Ireland, a former copper mine. In light of this discovery, two theories of possible introduction from Britain to Ireland were put forward: (1) an introduction from the 1800s and (2) a more recent introduction (2000s). Only male plants of the species are known, and reproduction and dispersal are therefore solely through asexual propagules and fragmentation. In order to address the conservation questions of the origin of the Irish population and to determine whether diversity exists within this rare species, genetic fingerprinting (amplified fragment length polymorphism) was carried out on the three known global populations. Percent polymorphism was found to be 7.29% and Nei's total gene diversity (HT) was 0.0356. AMOVA revealed that, of the small amount of variation found, the majority was among the three populations (98%). The presence of five private alleles in the Allihies population suggests a longer period of isolation than would fit either theory of introduction. Cluster analyses reveal that the Allihies population is more genetically distinct than the two British populations are to each other, thus heightening the conservation priority for this population. 相似文献