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171.
Qiaoqiao Xu Shanshan Huang Mingke Song Chuan-En Wang Sen Yan Xudong Liu Marta A. Gaertig Shan Ping Yu He Li Shihua Li Xiao-Jiang Li 《The Journal of cell biology》2013,202(7):1123-1138
Many genetic mouse models of Huntington’s disease (HD) have established that mutant huntingtin (htt) accumulates in various subcellular regions to affect a variety of cellular functions, but whether and how synaptic mutant htt directly mediates HD neuropathology remains to be determined. We generated transgenic mice that selectively express mutant htt in the presynaptic terminals. Although it was not overexpressed, synaptic mutant htt caused age-dependent neurological symptoms and early death in mice as well as defects in synaptic neurotransmitter release. Mass spectrometry analysis of synaptic fractions and immunoprecipitation of synapsin-1 from HD CAG150 knockin mouse brains revealed that mutant htt binds to synapsin-1, a protein whose phosphorylation is critical for neurotransmitter release. We found that polyglutamine-expanded exon1 htt binds to the C-terminal region of synapsin-1 to reduce synapsin-1 phosphorylation. Our findings point to a critical role for synaptic htt in the neurological symptoms of HD, providing a new therapeutic target. 相似文献
172.
Marta R. Hentschke Carlos E. Poli-de-Figueiredo Bartira E. Pinheiro da Costa Lesia O. Kurlak Paula J. Williams Hiten D. Mistry 《Journal of lipid research》2013,54(10):2658-2664
Atherosis of spiral arteries in uteroplacental beds from preeclamptic women resemble those of atherosclerosis, characterized by increased plasma lipids and lipoproteins. We hypothesized that: 1) lipoprotein receptors/transporters in the placenta would be upregulated in preeclampsia, associated with increased maternal and fetal lipoprotein concentrations; and 2) expression of these would be reduced in preeclamptic placentae from women delivering small-for-gestational-age (SGA) infants. Placental biopsies and maternal and umbilical serum samples were taken from 27 normotensive and 24 preeclamptic women. Maternal/umbilical cord serum LDL, HDL, total cholesterol, and triglycerides were measured. Placental mRNA expression of lipoprotein receptors/transporters were quantified using quantitative RT-PCR. Protein localization/expression of LDL receptor-related protein 1 (LRP-1) in the preeclamptic placentae with/without SGA was measured by immunohistochemistry. Placental mRNA expression of all genes except paraoxonase-1 (PON-1), microsomal triglyceride transfer protein (MTTP), and protein disulfide isomerase family A member 2 (PDIA2) were observed. No differences for any lipoprotein receptors/transporters were found between groups; however, in the preeclamptic group placental LRP-1 expression was lower in SGA delivering mothers (n = 7; P = 0.036). LRP-1 protein was localized around fetal vessels and Hofbauer cells. This is the first detailed study of maternal/fetal lipoprotein concentrations and placental lipoprotein receptor mRNA expression in normotensive and preeclamptic pregnancies. These findings do not support a role of altered lipid metabolism in preeclampsia, but may be involved in fetal growth. 相似文献
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Disulfated and trisulfated steroids have been synthesized from cholesterol and their acetylcholinesterase inhibitory activity has been evaluated. In our studies we have found that the activity was not only dependent on the location of the sulfate groups but on their configurations. 2β,3α,6α-trihydroxy-5α-cholestan-6-one trisulfate (18) was the most active steroid with an IC50 value of 15.48 μM comparable to that of 2β,3α-dihydroxy-5α-cholestan-6-one disulfate (1). Both compounds were found to be less active than the reference compound eserine. The butyrylcholinesterase activity of 1 and 18 was one magnitude lower than that against acetylcholinesterase revealing a selective inhibitor profile. 相似文献
176.
Sascha Naomi McKeon Marta Moreno Maria Anise Sallum Marinete Marins Povoa Jan Evelyn Conn 《Memórias do Instituto Oswaldo Cruz》2013,108(5):605-615
To evaluate whether environmental heterogeneity contributes to the
genetic heterogeneity in Anopheles triannulatus, larval habitat
characteristics across the Brazilian states of Roraima and Pará and genetic
sequences were examined. A comparison with Anopheles goeldii
was utilised to determine whether high genetic diversity was unique to
An. triannulatus. Student t test and
analysis of variance found no differences in habitat characteristics between the
species. Analysis of population structure of An. triannulatus
and An. goeldii revealed distinct demographic histories in a
largely overlapping geographic range. Cytochrome oxidase I
sequence parsimony networks found geographic clustering for both species;
however nuclear marker networks depicted An. triannulatus with
a more complex history of fragmentation, secondary contact and recent
divergence. Evidence of Pleistocene expansions suggests both species are more
likely to be genetically structured by geographic and ecological barriers than
demography. We hypothesise that niche partitioning is a driving force for
diversity, particularly in An. triannulatus. 相似文献
177.
Felix Willmund Marta del Alamo Sebastian Pechmann Taotao Chen Véronique Albanèse Eric B. Dammer Junmin Peng Judith Frydman 《Cell》2013,152(1-2):196-209
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178.
Juan Daniel Rivaldi Marta Luís C. Sousa Silva Luis C. Duarte António E. N. Ferreira Carlos Cordeiro Maria das Graças de Almeida Felipe Ana de Ponces Freire Ismael Maciel de Mancilha 《Applied microbiology and biotechnology》2013,97(4):1735-1743
Three probiotic Lactobacillus strains, Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus delbrueckii, were tested for their ability to assimilate and metabolize glycerol. Biodiesel-derived glycerol was used as the main carbon and energy source in batch microaerobic growth. Here, we show that the tested strains were able to assimilate glycerol, consuming between 38 and 48 % in approximately 24 h. L. acidophilus and L. delbrueckii showed a similar growth, higher than L. plantarum. The highest biomass reached was 2.11 g?L?1 for L. acidophilus, with a cell mass yield (Y X/S) of 0.37 g?g?1. L. delbrueckii and L. plantarum reached a biomass of 2.06 and 1.36 g?L?1. All strains catabolize glycerol mainly through glycerol kinase (EC 2.7.1.30). For these lactobacillus species, kinetic parameters for glycerol kinase showed Michaelis–Menten constant (K m) ranging from 1.2 to 3.8 mM. The specific activities for glycerol kinase in these strains were in the range of 0.18 to 0.58 U?mg?protein?1, with L. acidophilus ATCC 4356 showing the maximum specific activity after 24 h of cultivation. Glycerol dehydrogenase activity was also detected in all strains studied but only for the reduction of glyceraldehyde with NADPH (K m for DL-glyceraldehyde ranging from 12.8 to 32.3 mM). This enzyme shows a very low oxidative activity with glycerol and NADP+ and, most likely, under physiological conditions, the oxidative reaction does not occur, supporting the assumption that the main metabolic flux concerning glycerol metabolism is through the glycerol kinase pathway. 相似文献
179.
Simon W. Townsend Marta B. Manser 《Ethology : formerly Zeitschrift fur Tierpsychologie》2013,119(1):1-11
Whether animal vocalizations have the potential to communicate information regarding ongoing external events or objects has received considerable attention over the last four decades. Such ‘functionally referential signals’ (Macedonia & Evans 1993) have been shown to occur in a range of mammals and bird species and as a consequence have helped us understand the complexities that underlie animal communication, particularly how animals process and perceive their socio‐ecological worlds. Here, we review the existing evidence for functionally referential signals in mammals according to the framework put forward in the seminal Macedonia and Evans review paper. Furthermore, we elucidate the ambiguities regarding the functionally referential framework that have become obvious over the last years. Finally, we highlight new potential areas for investigation within referential signalling. We conclude the functionally referential framework is still informative when interpreting the meaning of animal vocalizations but, based on emerging research, requires further integration with other approaches investigating animal vocal complexity to broaden its applicability. 相似文献
180.