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71.
Multiple sclerosis (MS) is a chronic auto‐immune disease characterized by a damage to the myelin component of the central nervous system. Self‐antigens created by aberrant glycosylation have been described to be a key component in the formation of auto‐antibodies. CSF114(Glc) is a synthetic glucopeptide detecting in vitro MS‐specific auto‐antibodies, and it is actively used in diagnostics and research to monitor and quantify MS‐associated Ig levels. We reasoned that antibodies raised against this probe could have been relevant for MS. We therefore screened a human Domain Antibody library against CSF114(Glc) using magnetic separation as a panning method. We obtained and described several clones, and the one with the highest signals was produced as a 6×His‐tagged protein to properly study the binding properties as a soluble antibody. By surface plasmon resonance measurements, we evidenced that our clone recognized CSF114(Glc) with high affinity and specific for the glucosylated peptide. Kinetic parameters of peptide–clone interaction were calculated obtaining a value of KD in the nanomolar range. Harboring a human framework, this antibody should be very well tolerated by human immune system and may represent a valuable tool for MS diagnosis and therapy, paving the way to new research strategies. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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NAD plays essential redox and non-redox roles in cell biology. In mammals, its de novo and recycling biosynthetic pathways encompass two independent branches, the “amidated” and “deamidated” routes. Here we focused on the indispensable enzymes gating these two routes, i.e. nicotinamide mononucleotide adenylyltransferase (NMNAT), which in mammals comprises three distinct isozymes, and NAD synthetase (NADS). First, we measured the in vitro activity of the enzymes, and the levels of all their substrates and products in a number of tissues from the C57BL/6 mouse. Second, from these data, we derived in vivo estimates of enzymes''rates and quantitative contributions to NAD homeostasis. The NMNAT activity, mainly represented by nuclear NMNAT1, appears to be high and nonrate-limiting in all examined tissues, except in blood. The NADS activity, however, appears rate-limiting in lung and skeletal muscle, where its undetectable levels parallel a relative accumulation of the enzyme''s substrate NaAD (nicotinic acid adenine dinucleotide). In all tissues, the amidated NAD route was predominant, displaying highest rates in liver and kidney, and lowest in blood. In contrast, the minor deamidated route showed higher relative proportions in blood and small intestine, and higher absolute values in liver and small intestine. Such results provide the first comprehensive picture of the balance of the two alternative NAD biosynthetic routes in different mammalian tissues under physiological conditions. This fills a gap in the current knowledge of NAD biosynthesis, and provides a crucial information for the study of NAD metabolism and its role in disease.  相似文献   
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Maintaining the architecture, size and composition of an intact stem cell (SC) compartment is crucial for tissue homeostasis and regeneration throughout life. In mammalian skin, elevated expression of the anti‐apoptotic Bcl‐2 protein has been reported in hair follicle (HF) bulge SCs (BSCs), but its impact on SC function is unknown. Here, we show that systemic exposure of mice to the Bcl‐2 antagonist ABT‐199/venetoclax leads to the selective loss of suprabasal BSCs (sbBSCs), thereby disrupting cyclic HF regeneration. RNAseq analysis shows that the pro‐apoptotic BH3‐only proteins BIM and Bmf are upregulated in sbBSCs, explaining their addiction to Bcl‐2 and the marked susceptibility to Bcl‐2 antagonism. In line with these observations, conditional knockout of Bcl‐2 in mouse epidermis elevates apoptosis in BSCs. In contrast, ectopic Bcl‐2 expression blocks apoptosis during HF regression, resulting in the accumulation of quiescent SCs and delaying HF growth in mice. Strikingly, Bcl‐2‐induced changes in size and composition of the HF bulge accelerate tumour formation. Our study identifies a niche‐instructive mechanism of Bcl‐2‐regulated apoptosis response that is required for SC homeostasis and tissue regeneration, and may suppress carcinogenesis.  相似文献   
74.
A Norway spruce (Picea abies K.) cDNA library obtained from vegetative bud tissue was screened for the presence of (AG)n and (AC)n microsatellite repeats. Ten (AG)n and six (AC)n microsatellites were found, with an average length of 25.5 repeat units. Most of the microsatellites are simple perfect repeats. The microsatellite distribution within the clones is clearly non-random, with different classes of repeats lying in different positions relative to the coding region and in a highly conserved orientation. An estimate of the frequency of dinucleotide microsatellites in expressed regions was obtained, showing that SSRs (simple sequence repeats) are found in genes about 20 times less frequently than in random genomic clones, with (AG)n repeats more frequent than (AC)n repeats. Potential applications of these sequences as expressed region-based molecular markers are shown by developing six SSR markers for the detection of natural variation in Norway spruce populations and testing two of them for the identification of illegitimate progenies from a mapping population.  相似文献   
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Two-dimensional liquid chromatography separation (2-DL), based on chromatofocusing for first dimension and hydrophobicity for second, can be used as a complementary method to two-dimensional gel electrophoresis (2-DE). A platform now available, ProteomeLab PF 2D provided by Beckman Coulter, (Fullerton, CA, USA), assembles these methods in automation. This system was applied to resolve large numbers of urine proteins. Reproducibility and sensitivity in protein resolution were evaluated in this study using urines collected from male blood donors. About 1000 peaks were detected at a pH range of 4.0-8.5 by applying 1 mg of proteins. Furthermore, the same fractions showing peaks with high absorbance intensities in second dimension were collected and subjected to matrix-assisted laser desorption/ionization-time of flight/mass spectrometry analysis for identification. The results showed that the 2-DL provides high reproducibility of two-dimensional protein map, and lends fractions to subsequent mass spectrometry analysis without the further need for extraction or solubilization of samples as required for spots excised from 2-DE gels. In addition, this system also allows to separate particularly proteins with 40-9 kDa molecular weight.  相似文献   
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In nonhuman animals, the phenomenon of rapid facial mimicry (RFM)—the automatic, involuntary, and rapid (<1 s) replication of others’ facial expressions—has been mainly investigated in the playful domain. In immature lowland gorillas Gorilla gorilla gorilla both play face (PF) and full PF (FPF) are rapidly mimicked between the players. This makes the species suitable to test hypotheses on the factors influencing RFM during play. The observations on 3 captive groups of lowland gorillas (N = 27) revealed that contrary to expectations, the closeness of social bond negatively influenced the occurrence of RFM but it did not affect either RFM latency or its overlapping index (OVERLAP). RFM was affected by the degree of symmetry of play fighting: the more balanced the session, the higher the occurrence of RFM. Players of the same sex class responded faster than players of different sex. These findings suggest that RFM may help synchronizing behaviors of playmates matching in size (same-sex) and promote symmetric playful interactions. “Laughing together” (measured by the RFM OVERLAP) lasted longer when the responder perfectly mirrored the partner expression (PF→PF; FPF→FPF). If PF and FPF convey information on the different play roughness degree, through “laughing together” the players could coordinate their actions and share positive moods and playful intensity. If the perfect congruency in the motor resonance, also known as social sensitivity, can foster a possible emotional dialogue between gorillas remains to be investigated.  相似文献   
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