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371.
Molecular recognition of senescent cells involves oxidation of a crucial membrane protein leading to generation of a neoantigen, called 'senescent cell antigen' (SCA), and binding of physiologic autoantibodies. These IgG autoantibodies trigger macrophage removal of the cell prior to its lysis at a time when anion transport has decreased but the membrane is still grossly intact. The neoantigen SCA is generated by oxidation of a major anion transport protein called band 3 or anion exchange protein. In this study, we use IgG physiologic autoantibodies from senescent red cells to isolate SCA from brain, and HPLC and fast atom bombardment ionization mass spectrometry (FAB-MS) to compare brain SCA to band 3. HPLC peptide maps of band 3 and SCA showed substantial homology, suggesting that SCA is a subset of band 3, and includes an estimated >/=45% of the band 3 molecule. FAB-MS results indicate that residues matching all three band 3 isoforms (AE1, AE2 and AE3) are detected in SCA fractions. These findings suggest that other isoforms of band 3 may undergo the same aging changes that AE1 on red blood cells undergoes to generate SCA. This provides confirmation that SCA is on non-erythroid cell types. Implications of these studies to the generation of neoantigens by oxidation and their recognition by autoantibodies to them are discussed. 相似文献
372.
A section in the “Calcaires et Lignites de Sigonce” formation is described. Sedimentological study shows a swamp deposit. The collected Rodents and Insectivores teeth indicate a Middle Oligocene age (Antoingt level). Consequently, the Sigonce lignite and the basis of the Viens (Apt basin) and Bois d'Asson (Manosque trench) formations are correlated. 相似文献
373.
A new synthetic route to beta-cyclodextrin-linked hyaluronic acid (HA-CD) was developed. This was based on the preparation of a HA derivative selectively modified with adipic dihydrazide (HA-ADH) and a beta-cyclodextrin derivative possessing an aldehyde function on the primary face, followed by their coupling by a reductive amination-type reaction. The CD-polysaccharide was fully characterized in terms of chemical integrity and purity by high-resolution NMR spectroscopy. The complexation ability of the grafted CD was further demonstrated by isothermal titration calorimetry using sodium adamantane acetate (ADAc) and Ibuprofen as model guest molecules. The thermodynamic parameters for the complexation of these negatively charged guest molecules by the beta-CD grafted on negatively charged HA were shown to be largely influenced by the ionic strength of the aqueous medium. 相似文献
374.
Peter N. Herbert Trudy M. Forte Richard S. Shulman Marguerite J. La Piana Elaine L. Gong Robert I. Levy 《Preparative biochemistry & biotechnology》2013,43(2):93-129
The effects of repetitive ultracentrifugation on the physical and chemical properties of very low density lipoproteins (VLDL) were investigated. VLDL recentrifuged one to seven times were characterized by chemical analyses, analytical ultracentrifugation and electron microscopy. The VLDL content of triglyceride was increased and the proportion of phospholipid decreased by ultracentrifugation. Recentrifugation of VLDL decreased the number of Sf o 20–100 particles and generated particles of Sf o > 400. The bulk of the material removed from VLDL by ultracentrifugation was lipoprotein having pre-g mobility on paper electrophoresis, flotation rates of Sf o 10–100 and a particle size of 300–400 Å. Two ultracentrifugations separated an average of 14% of the starting VLDL protein. Characterization of the apoproteins in this material by polyacrylamide gel electrophoresis, gel chromatography, immuno precipitation and amino acid analysis demonstrated a relatively high proportion of B-apoprotein and relatively little C-apoproteins. 相似文献
375.
Background
Previous research has demonstrated the capacity of animal presence to stimulate social interaction among humans. The purpose of this study was to examine the interactions of children with autism spectrum disorder (ASD) with an adult and their typically-developing peers in the presence of animals (two guinea pigs) compared to toys.Methods
Ninety-nine children from 15 classrooms in 4 schools met the inclusion criteria and participated in groups of three (1 child with ASD and 2 typically-developing peers). Each group was video-recorded during three 10-minute, free-play sessions with toys and three 10-minute, free-play sessions with two guinea pigs. Two blinded observers coded the behavior of children with ASD and their peers. To account for the nested study design, data were analyzed using hierarchical generalized linear modeling.Results
Participants with ASD demonstrated more social approach behaviors (including talking, looking at faces, and making tactile contact) and received more social approaches from their peers in the presence of animals compared to toys. They also displayed more prosocial behaviors and positive affect (i.e., smiling and laughing) as well as less self-focused behaviors and negative affect (i.e., frowning, crying, and whining) in the presence of animals compared to toys.Conclusions
These results suggest that the presence of an animal can significantly increase positive social behaviors among children with ASD. 相似文献376.
Haifu Li Agnieszka Wozniak Raf Sciot Jasmien Cornillie Jasmien Wellens Thomas Van Looy Ulla Vanleeuw Marguerite Stas Daphne Hompes Maria Debiec-Rychter Patrick Schöffski 《Translational oncology》2014,7(6):665-671
INTRODUCTION: The rarity of dedifferentiated liposarcoma (DDLPS) and the lack of experimental DDLPS models limit the development of novel therapeutic strategies. Pazopanib (PAZ) is a tyrosine kinase inhibitor that is approved for the treatment of non-adipocytic advanced soft tissue sarcoma. The activity of this agent has not yet been properly explored in preclinical liposarcoma models nor in a randomized phase Ш clinical trial in this entity. The aim of the present study was to investigate whether PAZ had antitumor activity in DDLPS models in vivo. MATERIAL AND METHODS: We established two patient-derived DDLPS xenograft models (UZLX-STS3 and UZLX-STS5) through implantation of tumor material from sarcoma patients in athymic nude NMRI mice. An animal model of the SW872 liposarcoma cell line was also used. To investigate the efficacy of PAZ in vivo, mice bearing tumors were treated for 2 weeks with sterile water, doxorubicin (1.2 mg/kg, intraperitoneally, twice per week), PAZ [40 mg/kg, orally (p.o.), twice per day], or PAZ plus doxorubicin (same schedules as for single treatments). RESULTS: Patient-derived xenografts retained the histologic and molecular features of DDLPS. PAZ significantly delayed tumor growth by decreasing proliferation and inhibited angiogenesis in all models tested. Combining the angiogenesis inhibitor with an anthracycline did not show superior efficacy. CONCLUSION: These results suggest that PAZ has potential antitumor activity in DDLPS primarily through antiangiogenic effects and therefore should be explored in clinical trials. 相似文献
377.
Ashley D. Olson Laurence Meyer Maria Prins Rodolphe Thiebaut Deepti Gurdasani Marguerite Guiguet Marie-Laure Chaix Pauli Amornkul Abdel Babiker Manjinder S. Sandhu Kholoud Porter for C. A. S. C. A. D. E. Collaboration in EuroCoord 《PloS one》2014,9(1)
Background
Understanding the mechanisms underlying viral control is highly relevant to vaccine studies and elite control (EC) of HIV infection. Although numerous definitions of EC exist, it is not clear which, if any, best identify this rare phenotype.Methods
We assessed a number of EC definitions used in the literature using CASCADE data of 25,692 HIV seroconverters. We estimated proportions maintaining EC of total ART-naïve follow-up time, and disease progression, comparing to non-EC. We also examined HIV-RNA and CD4 values and CD4 slope during EC and beyond (while ART naïve).Results
Most definitions classify ∼1% as ECs with median HIV-RNA 43–903 copies/ml and median CD4>500 cells/mm3. Beyond EC status, median HIV-RNA levels remained low, although often detectable, and CD4 values high but with strong evidence of decline for all definitions. Median % ART-naïve time as EC was ≥92% although overlap between definitions was low. EC definitions with consecutive HIV-RNA measurements <75 copies/ml with follow-up≥ six months, or with 90% of measurements <400 copies/ml over ≥10 year follow-up preformed best overall. Individuals thus defined were less likely to progress to endpoint (hazard ratios ranged from 12.5–19.0 for non-ECs compared to ECs).Conclusions
ECs are rare, less likely to progress to clinical disease, but may eventually lose control. We suggest definitions requiring individuals to have consecutive undetectable HIV-RNA measurements for ≥ six months or otherwise with >90% of measurements <400 copies/ml over ≥10 years be used to define this phenotype. 相似文献378.
Fasching Christina Wilson Henry F. D’Amario Sarah C. Xenopoulos Marguerite A. 《Ecosystems》2019,22(7):1530-1545
Ecosystems - A shift in natural hydrologic patterns, such as increases in the frequency, and changes in the magnitude of flood events are expected with climate change. A better understanding of how... 相似文献
379.
A detailed assignment of the 13C chemical shifts of κ- and ι-carrageenans in their Na+ and K+ forms in D2O and dimethylsulfoxide is given. Evidence of the conformational transition induced by temperature variation in the absence of any gel formation on κ-carrageenans is also presented. This evidence is based on 13C-nmr and optical rotation experiments. 相似文献
380.
Hailu Kinde Constantin A. Genigeorgis Marguerite Pappaioanou 《Applied microbiology》1983,45(3):1116-1118
Campylobacter jejuni was found in 82.9% of 94 chicken wing packages analyzed on the day of arrival at supermarkets and in 15.5% of 45 packages obtained from the supermarket shelves a few days later. The number of bacterial cells ranged from 102 to 103.9 per wing. The prevalence of C. jejuni in the wings varied with the brand, the day of sampling, and the age of the product. 相似文献