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181.
Chrysiis Michaloglou Waltraut Lehmann Typhaine Martin Clara Delaunay Andreas Hueber Louise Barys Honglin Niu Eric Billy Markus Wartmann Moriko Ito Christopher J. Wilson Mary Ellen Digan Andreas Bauer Hans Voshol Gerhard Christofori William R. Sellers Francesco Hofmann Tobias Schmelzle 《PloS one》2013,8(4)
182.
Bonnet Xavier Billy Gopal Lakušić Margareta 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2020,190(3):341-347
Journal of Comparative Physiology B - The prerogative of animal welfare science includes wild species and ecological studies. Yet, guidance enshrined in legislation is narrowly derived from studies... 相似文献
183.
McKinnon LR Nyanga B Chege D Izulla P Kimani M Huibner S Gelmon L Block KE Cicala C Anzala AO Arthos J Kimani J Kaul R 《Journal of immunology (Baltimore, Md. : 1950)》2011,187(11):6032-6042
The HIV pandemic disproportionately affects women, with most infections acquired through receptive vaginal sex. Although the target cells by which HIV establishes infection in the female genital tract remain poorly defined, it is known that immune activation results in CD4(+) T cells with enhanced susceptibility, as does expression of the mucosal integrin α4β7 and the HIV coreceptor CCR5. Blood and cervical cytobrush specimens were collected from female sex workers (FSWs) in Nairobi, Kenya. Genital infection diagnostics were performed, T cell populations were defined by multiparameter flow cytometry based on their expression of surface receptors relevant to mucosal homing and/or HIV acquisition, and cytokine production was assayed by intracellular cytokine staining. The integrin α4β7 was expressed on 26.0% of cervical CD4(+) T cells, and these cells were more likely to express both the HIV coreceptor CCR5 (p < 0.0001) and the early activation marker CD69 (p < 0.0001) but not CXCR4 (p = 0.34). Cervical Th17 frequencies were enhanced compared with blood (7.02 versus 1.24%; p < 0.0001), and cervical IL-17A(+) CD4(+) T cells preferentially coexpressed α4β7 and CCR5. Expression of IFN-γ and IL-22 was greater in cervical Th17 cells than in blood Th17 cells. In keeping with the hypothesis that these cells are preferential HIV targets, gp120 preferentially bound CCR5(+) cervical T cells, and cervical Th17 cells were almost completely depleted in HIV(+) FSWs compared with HIV(-) FSWs. In summary, a subset of Th17 CD4(+) T cells in the cervical mucosa coexpresses multiple HIV susceptibility markers; their dramatic depletion after HIV infection suggests that these may serve as key target cells during HIV transmission. 相似文献
184.
The genus Elminia has had a jumbled taxonomic history, being placed among ‘old world flycatchers’ or ‘monarch flycatchers’, where it was for a long time lumped with Trochocercus. It was recently suggested that it might represent a deep clade in the large sylvioid radiation. Using one mitochondrial protein‐coding gene (ND2, 1041 bp) and one nuclear intron (myoglobin intron 2, 700 bp) DNA sequences, we obtained robust evidence for the phylogenetic placement of Elminia in the new family Stenostiridae, which is strongly supported by a synapomorphic insertion of one base in the nuclear myoglobin intron 2 sequence. Our analyses confirm the monophyly of Elminia and resolve relationships within this genus, but cannot confidently identify its sister‐taxon within the stenostirid clade. Two clades were strongly supported within the genus Elminia: one with the two fairy blue flycatchers and another with the three white‐tailed crested‐flycatchers. Within the first clade, Elminia longicauda appears non‐monophyletic but remains strongly related to E. albicauda. In the second clade, E. albiventris is sister to E. albonotata while the Dusky Crested Flycatcher (E. nigromitrata) appears in a basal position within this clade. According to our molecular dating, several geological events in western Africa and the Albertine Rift area seem to be related to the historical distribution of Elminia. Thus, the differentiation between E. albonotata and E. albiventris could be directly related to the tectonic history of these two regions. According to our molecular dating, at least one intercontinental dispersal event involving Culicicapa took place within the Stenostiridae clade at a time when the Middle East was forested. 相似文献
185.
186.
Bourne C Roy S Wiley JL Martin BR Thomas BF Mahadevan A Razdan RK 《Bioorganic & medicinal chemistry》2007,15(24):7850-7864
The structure–activity relationship (SAR) of the end pentyl chain in anandamide (AEA) has been established to be very similar to that of Δ9-tetrahydrocannabinol (Δ9-THC). In order to broaden our understanding of the structural similarities between AEA and THC, hybrid structures 1–3 were designed. In these hybrids the aromatic ring of THC–DMH was linked to the AEA moiety through an ether linkage with the oxygen of the phenol of THC. Hybrid 1 (O-2220) was found to have very high binding affinity to CB1 receptors (Ki = 8.5 nM), and it is interesting to note that the orientation of the side chain with respect to the oxygen in the phenol is the same as in THCs. To further explore the SAR in this series the terminal carbon of the side chain was modified by adding different substituents. Several such analogs were synthesized and tested for their CB1 and CB2 binding affinities and in vivo activity (tetrad tests). The details of the synthesis and the biological activity of these compounds are described. 相似文献
187.
188.
R. Stringwell A. Lock C. J. Stutchbury E. Baggett J. Taylor P. J. Gough C. Garcia de Leaniz 《Journal of fish biology》2014,85(6):1927-1945
Changes in body shape, fluctuating asymmetry (FA) and crypsis were compared among Atlantic salmon Salmo salar fry kept as controls in captivity and those released and subsequently recaptured in the wild according to a before‐after‐control‐impact (BACI) design. Hatchery fish that survived in the wild became more cryptic and displayed a much lower incidence of fin erosion and of asymmetric individuals than control fish kept in captivity. Significant differences in body shape were also apparent, and survivors had longer heads, thicker caudal peduncles and a more streamlined body shape than hatchery controls as early as 20 days following stocking, most likely as a result of phenotypic plasticity and non‐random, selective mortality of maladapted phenotypes. Hatchery‐reared fish typically perform poorly in the wild and the results of this study indicate that this may be due to phenotypic mismatch, i.e. because hatcheries generate fish that are phenotypically mismatched to the natural environment. 相似文献
189.
Huffman JW Mabon R Wu MJ Lu J Hart R Hurst DP Reggio PH Wiley JL Martin BR 《Bioorganic & medicinal chemistry》2003,11(4):539-549
A series of 1-pentyl-1H-indol-3-yl-(1-naphthyl)methanes (9-11) and 2-methyl-1-pentyl-1H-indol-3-yl-(1-naphthyl)methanes (12-14) have been synthesized to investigate the hypothesis that cannabimimetic 3-(1-naphthoyl)indoles interact with the CB(1) receptor by hydrogen bonding to the carbonyl group. Indoles 9-11 have significant (K(i)=17-23nM) receptor affinity, somewhat less than that of the corresponding naphthoylindoles (5, 15, 16). 2-Methyl-1-indoles 12-14 have little affinity for the CB(1) receptor, in contrast to 2-methyl-3-(1-naphthoyl)indoles 17-19, which have affinities comparable to those of 5, 15, 16. A cannabimimetic indene hydrocarbon (26) was synthesized and found to have K(i)=26+/-4nM. Molecular modeling and receptor docking studies of naphthoylindole 16, its 2-methyl congener (19) and indolyl-1-naphthylmethanes 11 and 14, combined with the receptor affinities of these cannabimimetic indoles, strongly suggest that these cannabinoid receptor ligands bind primarily by aromatic stacking interactions in the transmembrane helix 3-4-5-6 region of the CB(1) receptor. 相似文献
190.
Brooke M. Steenhard Roberto Vanacore David Friedman Adrian Zelenchuk Larysa Stroganova Kathryn Isom Patricia L. St. John Billy G. Hudson Dale R. Abrahamson 《PloS one》2012,7(12)
Alport disease in humans, which usually results in proteinuria and kidney failure, is caused by mutations to the COL4A3, COL4A4, or COL4A5 genes, and absence of collagen α3α4α5(IV) networks found in mature kidney glomerular basement membrane (GBM). The Alport mouse harbors a deletion of the Col4a3 gene, which also results in the lack of GBM collagen α3α4α5(IV). This animal model shares many features with human Alport patients, including the retention of collagen α1α2α1(IV) in GBMs, effacement of podocyte foot processes, gradual loss of glomerular barrier properties, and progression to renal failure. To learn more about the pathogenesis of Alport disease, we undertook a discovery proteomics approach to identify proteins that were differentially expressed in glomeruli purified from Alport and wild-type mouse kidneys. Pairs of cy3- and cy5-labeled extracts from 5-week old Alport and wild-type glomeruli, respectively, underwent 2-dimensional difference gel electrophoresis. Differentially expressed proteins were digested with trypsin and prepared for mass spectrometry, peptide ion mapping/fingerprinting, and protein identification through database searching. The intermediate filament protein, vimentin, was upregulated ∼2.5 fold in Alport glomeruli compared to wild-type. Upregulation was confirmed by quantitative real time RT-PCR of isolated Alport glomeruli (5.4 fold over wild-type), and quantitative confocal immunofluorescence microscopy localized over-expressed vimentin specifically to Alport podocytes. We next hypothesized that increases in vimentin abundance might affect the basement membrane protein receptors, integrins, and screened Alport and wild-type glomeruli for expression of integrins likely to be the main receptors for GBM type IV collagen and laminin. Quantitative immunofluorescence showed an increase in integrin α1 expression in Alport mesangial cells and an increase in integrin α3 in Alport podocytes. We conclude that overexpression of mesangial integrin α1 and podocyte vimentin and integrin α3 may be important features of glomerular Alport disease, possibly affecting cell-signaling, cell shape and cellular adhesion to the GBM. 相似文献