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991.
The β(1,2)-xylose- and/or α(1,3)-fucose-containing cross-reactive carbohydrate determinants (CCDs) are present in various plant and insect N-glycans, and have been attracted as potential antigens in IgE-mediated allergies and immunologically undesired post-translational products on some recombinant therapeutic proteins. By using ELISA and immunoblotting, CCDs-specific IgG and IgE antibodies from some, but not all, of mice and humans were found to fully retain their binding activity after a typical periodate-treatment to CCDs, which did cause the CCDs’ antigenic activity to those from the other mice and rabbits to disappear almost completely. Furthermore, the mouse IgE recognizing the periodate-resistant CCDs induced the CCDs/IgE-dependent degranulation of rat basophilic RBL-2H3 cells. These findings indicate that in some cases CCDs include those dependent of the core trisaccharide more strongly than the terminal xylose and fucose, which might have been screened out in the CCDs analyses based on the loss of antibody-binding by the periodate-treatment.  相似文献   
992.
In the epithelia and endothelia, tight junctions regulate the movement of several substances through the paracellular pathway, maintaining several gradients between apical and basal compartments including osmolality and hydrostatic pressure. In this study, we show that the change of hydrostatic pressure gradient affected tight junctions as well as actin cytoskeleton, cell height and transcellular ion transport. Hydrostatic pressure gradient from basolateral to apical side increased transepithelial conductance and altered claudin-1 localization within several tens of minutes. These changes were promptly restored by the elimination of hydrostatic pressure gradient. Hydrostatic pressure gradient also induced dynamic changes in the actin structure and cell height. We further found that hydrostatic pressure gradient from basolateral to apical side stimulates transcellular Cl transport. Our present findings indicate that the epithelial cell structures and functions are regulated by the hydrostatic pressure gradient which is generated and maintained by the epithelia themselves.  相似文献   
993.
994.

Background  

Identification and characterization of intervening sequences (IVSs) within 23S rRNA genes from Campylobacter organisms including atypical campylobacters were carried out using two PCR primer pairs, designed to generate helix 25 and 45 regions.  相似文献   
995.
Oryzias luzonensis is closely related to the medaka, O. latipes. The sex of both species is determined by an XX‐XY system. However, the testis determining gene (DMY/Dmrt1bY) found in O. latipes does not exist in O. luzonensis. Instead, a different gene is thought to act as a testis determining gene. In this study, we focused the gonadal sex differentiation process in O. luzonensis under different testis determining gene. First, we observed the gonadal development of O. luzonensis histologically. We then analyzed the expression of Sox9a2/Sox9b, Dmrt1, and Foxl2 during early development. Our results suggest that the sexual differentiation of germ cells in O. luzonensis is initiated later than in O. latipes. However, the timing of the sexual differentiation of the supporting cell linage is similar between the species. genesis 47:289–299, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
996.
Protein glycosylation is a critical subject attracting increasing attention in the field of proteomics as it is expected to play a key role in the investigation of histological and diagnostic biomarkers. In this context, an enormous number of glycoproteins have now been nominated as disease-related biomarkers. However, there is no appropriate strategy in the current proteome platform to qualify such marker candidate molecules, which relates their specific expression to particular diseases. Here, we present a new practical system for focused differential glycan analysis in terms of antibody-assisted lectin profiling (ALP). In the developed procedure, (i) a target protein is enriched from clinic samples (e.g. tissue extracts, cell supernatants, or sera) by immunoprecipitation with a specific antibody recognizing a core protein moiety; (ii) the target glycoprotein is quantified by immunoblotting using the same antibody used in (i); and (iii) glycosylation difference is analyzed by means of antibody-overlay lectin microarray, an application technique of an emerging glycan profiling microarray. As model glycoproteins having either N-linked or O-linked glycans, prostate-specific antigen or podoplanin, respectively, were subjected to systematic ALP analysis. As a result, specific signals corresponding to the target glycoprotein glycans were obtained at a sub-picomole level with the aid of specific antibodies, whereby disease-specific or tissue-specific glycosylation changes could be observed in a rapid, reproducible, and high-throughput manner. Thus, the established system should provide a powerful pipeline in support of on-going efforts in glyco-biomarker discovery.  相似文献   
997.

Background

Mutations in the integral membrane protein 2B [1], also known as BRI2 [2], a type II trans-membrane domain protein cause two autosomal dominant neurodegenerative diseases, Familial British and Danish Dementia [3]. In these conditions, accumulation of a C-terminal peptide (ABri and ADan) cleaved off from the mutated precursor protein by the pro-protein convertase furin [4], leads to amyloid deposition in the walls of blood vessels and parenchyma of the brain. Recent advances in the understanding of the generation of amyloid in Alzheimer''s disease has lead to the finding that BRI2 interacts with the Amyloid Precursor Protein (APP), decreasing the efficiency of APP processing to generate Aβ [5], [6], [7]. The interaction between the two precursors, APP and BRI2, and possibly between Aβ and ABri or ADan, could be important in influencing the rate of amyloid production or the tendency of these peptides to aggregate.

Methodology/Principal Findings

We have generated the first BRI2 Danish Knock-In (FDDKI) murine model of FDD, expressing the pathogenic decamer duplication in exon 6 of the BRI2 gene. FDDKI mice do not show any evident abnormal phenotype, with normal brain histology and no detectable amyloid deposition in blood vessel walls or parenchyma.

Conclusions/Significance

This new murine mouse model will be important to further understand the interaction between APP and BRI2, and to provide insights into the molecular basis of FDD.  相似文献   
998.
Anthranilate synthase (AS) is a key regulatory enzyme in tryptophan (Trp) biosynthesis and is subject to feedback inhibition by Trp. The gene encoding a mutated feedback-resistant α subunit of rice AS (OASA1D) under the control of either a soybean glycinin gene promoter or the 35S promoter of cauliflower mosaic virus for seed-specific or constitutive expression, respectively, was introduced into soybean [Glycine max (L.) Merrill] by particle bombardment. A total of seven different transgenic lines that showed markedly increased accumulation of free Trp in their seeds were developed. The overproduction of free Trp was stably inherited in subsequent generations without any apparent detrimental effect on plant growth or reproduction. The total Trp content of transgenic seeds was also about twice that of nontransgenic seeds, whereas the amount of protein-bound Trp was not substantially affected by OASA1D expression. In spite of the marked increase in free Trp content, metabolic profiling by high-performance liquid chromatography coupled with mass spectrometry revealed little change in the amounts of other aromatic compounds in the transgenic seeds. We developed a rapid and feasible system based on farmed rainbow trout to evaluate the nutritional quality of a limited quantity of transgenic soybean seeds. Supplementation of fish food with OASA1D transgenic soybean seeds or with nontransgenic seeds plus crystalline Trp increased the growth rate of the farmed fish. These results indicate transformation with OASA1D is a reliable approach to improve the nutritional quality of soybean (or of other grain legumes) for human and animal food.  相似文献   
999.
Non-obese diabetic (NOD) mice develop Sjögren's-like syndrome (Ss) and a gradual loss of saliva secretory function. Our previous study showed that injections of matched normal spleen cells with Complete Freund's Adjuvant (CFA) reversed salivary gland dysfunction in 14-week-old NOD mice, which had established Ss. The spleen and bone marrow are closely related organs, and both are among the first sites of hematopoiesis during gestation. Noticing a rapidly increasing number of clinical trials using bone marrow (BM) cells treatments for autoimmune diseases, we tested if BM cells can prevent Ss and restore salivary glands’ function. We injected CFA and MHC class I-matched normal BM cells in 7-week-old NOD mice, which had not yet developed Ss. We found at week 52 post-treatment that all NOD mice receiving BM cells and CFA had a recovery of salivary flow and were protected from Ss and diabetes. BM cells-treated mice had their salivary function restored quantitatively and qualitatively. Saliva flow was higher (p < 0.05) in BM cells-transplanted mice when compared to control mice, which continued to deteriorate over time. Total proteins, epidermal growth factor, amylase, and electrolytes concentrations in saliva of BM cells-treated mice were not significantly changed at week 44 and 52 post-therapy when compared to pre-therapy (when the mice did not have Ss). Restoration of salivary flow could have resulted from a combination of rescue and paracrine effects from BM cells. This study suggests that a combined immuno- and cell-based therapy can permanently prevent Ss and restored salivary function in NOD mice.  相似文献   
1000.
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