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41.
Novel acidic oligosaccharides were isolated in large amounts by reductive alkaline treatment of the jelly coat of Pleurodeles waltlii (Michah) eggs. The oligosaccharides were found to contain the newly described KDN as acidic monosaccharide and possess either the Le(x), Le(y) and A Le(y) antigenic determinants. Occurrence of Le(x) and Le(y) determinants previously recognized as tumor-associated antigen (TAA) demonstrates that mucins of lower animals may represent a rich and easily available source for preparing TAA. Moreover, it reinforces the hypothesis according to which TAA are evolution markers.  相似文献   
42.
Four platinum(II) aminobenzamidine complexes have been prepared and characterized by IR and 1H and 13C NMR spectroscopy, and tested for their ability to interact with the nicked and closed circular forms of the pUC8 plasmid DNA. The results show that the complexes of formula [Pt(LH)2Cl2]2X have a cis- geometry with an amino-Pt bonding, where L is either p- or m-aminobenzamidine and where 2X is 2Cl- or PtCl4(2-). It was observed that these complexes significantly alter the electrophoretic mobility of nicked and closed circular forms of DNA and that the alteration in electrophoretic mobility due to Pt(II)-p-aminobenzamidine binding is higher than that due to Pt(II)-m-aminobenzamidine. No difference in mobility was observed whether the DNA interacted with complexes having as counteranion Cl- or PtCl4(2-). The synthesized compounds were, in addition, assayed for antitumor activity in vitro against colon (CX-1), lung (LX-1), and mammary (MX-1) human tumor cells. The results show that these complexes inhibited the multiplication of the tumor cells and that they show higher specificity for lung cells.  相似文献   
43.
Summary It is known that human and animal fibroblasts are able to induce the retraction of a fibrin clot. In the present study the correlation between (i) fibrinclot retractile (FCR) activity, (ii) the number of actin stress-lines in mouse fibroblasts during growth in culture, and (iii) the sensitivity of actin stress-lines to a powerful actin-depolymerizing factor (ADF), present in plasma and serum of humans and laboratory animals was investigated. Fibroblasts at early passages (2–4) were tested for these parameters at various intervals after seeding (24, 96, and 168 h). The number of actin stress-lines was progressively higher, while the sensitivity to ADF action was progressively lower in cells cultured from 24 to 168 h; the FCR capacity was significantly decreased at 168 h. These data suggest that cells containing weakly polymerized and/or stabilized actin are more active than those containing highly polymerized and/or stabilized actin in triggering fibroblast contraction.  相似文献   
44.
Complex and simple sequences in human repeated DNAs   总被引:9,自引:0,他引:9  
Highly repeated human DNA sequences were isolated by isopycnic centrifugation, or were eluted from gels after restriction enzyme cleavage. High molecular weight DNA peaks separable from the bulk of the DNA in a variety of gradients were shown to consist of very simple sequences characteristic of simple satellite DNAs; DNA fingerprint studies indicated each of these peaks could consist of tandem repeats of a specific oligonucleotide sequence as low as 10 base pairs (bp) long. All the gradient peaks could be assigned to one of two sequence groups and several different buoyant density peaks revealed the same sequence. — Restriction fragment multimers did not share common sequences with the satellite DNAs as judged by hybridization data. They could not be separated by isopycnic centrifugation. Furthermore these highly repeated DNAs were more complex in sequence and more variable than the satellites. Even the smallest (50 bp) fragments by depurination and other direct sequencing methods were shown to be more complex than the high molecular weight satellite peaks. — The idea that subsets of repeated DNAs may be defined by sequence complexity, possibly with discrete or separable functions, is proposed.  相似文献   
45.
Summary Hindgut epithelial cells of the aquatic isopod,Asellus communis, and the terrestrial isopod,Armadillidium vulgare, possess annulate lamellae. The organelle is present in non-dividing cells of intermolt adult organisms. The lamellae exhibit dense pore areas traversed by diaphragms, and the lamellae are associated with elements of endoplasmic reticulum.This research was supported in part by a grant to E. R. Witkus from the Irene Heinz and John La Porte Given Foundation.  相似文献   
46.
47.
IL-17 inhibitors (IL-17i) are medicines used to treat dermatological and rheumatic diseases They belong to a class of medicines called biological disease-modifying anti-rheumatic drugs (bDMARDs). This class of drugs has had a major impact on the therapy of autoimmune diseases, being much safer and more effective than treatment with small molecules. At the same time, they have highly beneficial effects on skin and joint changes, and their efficacy has been extensively monitored and demonstrated in numerous clinical trials. More and more such drugs are still being discovered today to ensure the best possible treatment of these patients, but more frequently and relatively constantly three agents are used. Two of them (Secukinumab and Ixekizumab) inhibit IL-17A directly, and the third, Brodamulab, inhibits the IL-17A receptor. Although they are extremely effective in the treatment of these diseases, sometimes their administration has been associated with paradoxical effects, i.e., there is an exacerbation of the inflammatory process. Tough, clinical trials of IL-17i have described cases of exacerbation or even onset of inflammatory bowel disease (IBD), such as Crohn’s disease and ulcerative colitis, after administration of these drugs in patients previously diagnosed with psoriasis (PS), psoriatic arthritis (PsA), or ankylosing spondylitis (AS). The pathophysiological mechanism of action is not well understood at present. One explanation would be that this hyperreactive inflammatory process would be triggered by Interferon 1 derived from dendritic plasma cells. Even though there are many reports in the recent literature about the role of IL17i in the onset of IBD, conclusions of studies do not converge. Some of them show an increased incidence of IBD in patients treated with IL17i, while some others affirm their safety of them. In the near future we will surely have more data emerging from ongoing meta-analyses regarding safety of use IL17i in patients who are at risk of developing IBD. Clinical and paraclinical evaluation (inflammatory intestinal markers) are carefully advised before recommending treatment with IL-17i and after initiation of treatment, and prospective surveillance by clinical and biomarkers of patients treated with IL-17i is absolutely essential to capture the onset of IBD.  相似文献   
48.
49.
Healthy blood plasma is required for several therapeutic procedures. To maximize successful therapeutic outcomes it is critical to control the quality of blood plasma. Clearly initiatives to improve the safety of blood transfusions will have a high economical and social impact. A detailed knowledge of the composition of healthy blood plasma is essential to facilitate such improvements. Apart from free proteins, lipids and metabolites, blood plasma also contains cell-derived microvesicles, including exosomes and microparticles from several different cellular origins. In this study, we have purified microvesicles smaller than 220nm from plasma of healthy donors and performed proteomic, ultra-structural, biochemical and functional analyses. We have detected 161 microvesicle-associated proteins, including many associated with the complement and coagulation signal-transduction cascades. Several proteases and protease inhibitors associated with acute phase responses were present, indicating that these microvesicles may be involved in these processes. There was a remarkably high variability in the protein content of plasma from different donors. In addition, we report that this variability could be relevant for their interaction with cellular systems. This work provides valuable information on plasma microvesicles and a foundation to understand microvesicle biology and clinical implications.  相似文献   
50.
It has been well documented that genetic factors can influence predisposition to develop alcoholism. While the underlying genomic changes may be of several types, two of the most common and disease associated are copy number variations (CNVs) and sequence alterations of protein coding regions. The goal of this study was to identify CNVs and single-nucleotide polymorphisms that occur in gene coding regions that may play a role in influencing the risk of an individual developing alcoholism. Toward this end, two mouse strains were used that have been selectively bred based on their differential sensitivity to alcohol: the Inbred long sleep (ILS) and Inbred short sleep (ISS) mouse strains. Differences in initial response to alcohol have been linked to risk for alcoholism, and the ILS/ISS strains are used to investigate the genetics of initial sensitivity to alcohol. Array comparative genomic hybridization (arrayCGH) and exome sequencing were conducted to identify CNVs and gene coding sequence differences, respectively, between ILS and ISS mice. Mouse arrayCGH was performed using catalog Agilent 1 × 244 k mouse arrays. Subsequently, exome sequencing was carried out using an Illumina HiSeq 2000 instrument. ArrayCGH detected 74 CNVs that were strain-specific (38 ILS/36 ISS), including several ISS-specific deletions that contained genes implicated in brain function and neurotransmitter release. Among several interesting coding variations detected by exome sequencing was the gain of a premature stop codon in the alpha-amylase 2B (AMY2B) gene specifically in the ILS strain. In total, exome sequencing detected 2,597 and 1,768 strain-specific exonic gene variants in the ILS and ISS mice, respectively. This study represents the most comprehensive and detailed genomic comparison of ILS and ISS mouse strains to date. The two complementary genome-wide approaches identified strain-specific CNVs and gene coding sequence variations that should provide strong candidates to contribute to the alcohol-related phenotypic differences associated with these strains.  相似文献   
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