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81.
Barbara A Malynn Albert C Shaw Faith Young Valerie Stewart Frederick W Alt 《Molecular immunology》2002,38(7):547-556
Early stages of B cell development are dependent on the expression of a pre-B cell receptor (BCR), composed of a mu heavy chain (HC) in association with surrogate light chain (SLC) proteins and the signaling molecules, Igalpha and Igbeta. During the formation of the variable region of the mu chain by somatic gene rearrangement, a truncated form of the mu protein (called Dmu) is sometimes produced by the rearrangement of a D(H) segment to a J(H) segment using one of three reading frames (designated rf2). When a Dmu protein is formed, subsequent B cell development is blocked by down-regulation of further HC rearrangements, so that a full-length muHC cannot be formed. In this study, we demonstrate that in recombinase activating gene (RAG)-2-deficient B220(+) CD43(+) pro-B cells in which B lymphopoiesis has been arrested at fraction C, transgenic expression of Dmu promoted partial developmental progression to fraction C', but was unable to mediate the pro-B to pre-B cell transition to fraction D effected by full-length muHC protein. These data suggest that the intracellular signaling pathways engaged by the Dmu pre-BCR are insufficient to facilitate the expansion and/or survival of pre-B cells, and are distinct from those engaged by the pre-BCR-containing full-length muHC. 相似文献
82.
83.
Peroxidase conjugates for demonstration of tissue antibodies: evaluation of the technique 总被引:3,自引:3,他引:3
Conjugates of antibody with the enzyme marker, peroxidase, are relatively easy to prepare and can be shown to have a sensitivity in the indirect test for antinuclear antibodies which is entirely comparable to that obtained with fluorescein labelled material. Clear cut results were obtained in tests for autoantibodies on tissue sections and for bound IgG in biopsies using an antihuman immunoglobulin conjugate. Antibodies to Treponema pallidum were also readily demonstrable. Only a simple light microscope is required, slides can be read without fatigue and the morphology of the tissue section can be easily assessed. It is concluded that the peroxidase technique offers a useful alternative to immunofluorescence. 相似文献
84.
P Waring M Egan A Braithwaite A Mullbacher A Sjaarda 《International journal of immunopharmacology》1990,12(4):445-457
Incubation of 48 h concanavalin A stimulated spleen cells (T blasts) and murine peritoneal macrophages with the mycotoxin sporidesmin results in DNA fragmentation characteristic of apoptosis. Morphological changes, particularly condensed chromatin, observed following incubation of these cells with sporidesmin and the immunotoxin gliotoxin and related epipolythiodioxopiperazines (ETP) also show changes characteristic of apoptosis. The presence of Zn2+ salts in the culture medium at concentrations non toxic to the cells over the time period studied protects against DNA damage and morphological change. Interaction between Zn2+ and the reduced form of a simple ETP compound assessed by spectral changes demonstrated the formation of a weak complex between the two molecules. Complex formation between zinc and thiol however was insufficient to prevent oxidative damage to plasmid DNA in vitro by inhibiting auto-oxidation of the reduced ETP compound because of the looseness of the interaction. Cd2+, which appears to form a tighter complex with the dithiol does inhibit cleavage of plasmid DNA. These results establish that the toxicity of sporidesmin may be due in part to its ability to induce apoptosis or programmed cell death in sensitive cells. In addition the immunotoxin gliotoxin and related compounds have now been shown to induce the same characteristic morphological changes in cells of haemopoietic origin. The inhibition of apoptosis induced by ETP compounds by Zn2+ appears to be due to direct inhibition of apoptosis rather than Zn2+ acting as an antioxidant. These results demonstrate the inhibition of apoptosis induced by ETP compounds by Zn2+ and suggest an alternate explanation for the known prophylactic effect of Zn2+ on sporidesmin induced tissue damage. 相似文献
85.
Endoplasmic reticulum stress and unfolded protein response in inclusion body myositis muscle 总被引:11,自引:0,他引:11 下载免费PDF全文
Proteins in the endoplasmic reticulum (ER) require an efficient system of molecular chaperones whose role is to assure their proper folding and to prevent accumulation of unfolded proteins. The response of cells to accumulation of unfolded proteins in the ER is termed "unfolded protein response" (UPR). UPR is a functional mechanism by which cells attempt to protect themselves against ER stress, resulting from the accumulation of the unfolded/misfolded proteins. Because intracellular inclusions, containing either amyloid-beta (Abeta) or phosphorylated tau, are the characteristic feature of sporadic inclusion body myositis (s-IBM) muscle biopsies, we studied expression and immunolocalization of five ER chaperones, calnexin, calreticulin, GRP94, BiP/GRP78, and ERp72, in s-IBM and control muscle biopsies. Physical interaction of the ER chaperones with amyloid-beta precursor protein (AbetaPP) was studied by a combined immunoprecipitation/immunoblotting technique in s-IBM and control muscle biopsies, and in AbetaPP-overexpressing cultured human muscle fibers. In all s-IBM muscle biopsies, all five of the ER chaperones were immunodetected in the form of inclusions that co-localized with amyloid-beta. By immunoblotting, expression of ER chaperones was greatly increased as compared to the controls. By immunoprecipitation/immunoblotting experiments, ER chaperones co-immunoprecipitated with AbetaPP. Our studies provide evidence of the UPR in s-IBM muscle and demonstrate for the first time that the ER chaperones calnexin, calreticulin, GRP94, BiP/GRP78, and ERp72 physically associate with AbetaPP in s-IBM muscle, suggesting their playing a role in AbetaPP folding and processing. 相似文献
86.
The gut is a pivotal organ in health and disease. The events that take place in the gut during early life contribute to the programming, shaping and tuning of distant organs, having lifelong consequences. In this context, the maternal gut plays a quintessence in programming the mammary gland to face the nutritional, microbiological, immunological, and neuroendocrine requirements of the growing infant. Subsequently, human colostrum and milk provides the infant with an impressive array of nutrients and bioactive components, including microbes, immune cells, and stem cells. Therefore, the axis linking the maternal gut, the breast, and the infant gut seems crucial for a correct infant growth and development. The aim of this article is not to perform a systematic review of the human milk components but to provide an insight of their extremely complex interactions, which render human milk a unique functional food and explain why this biological fluid still truly remains as a scientific enigma. 相似文献
87.
Valerie Hruska Nitin Shivappa James R. Hbert Alison M. Duncan Jess Haines David W. L. Ma 《Nutrients》2021,13(5)
Chronic stress is known to influence dietary choices, and stressed families often report poorer diet quality; however, little is known about how family-based stress is linked with dietary patterns that promote inflammation. This study investigated associations between family-based stress and the inflammatory potential of the diet among preschool-aged children and their parents. Parents (n = 212 mothers, n = 146 fathers) and children (n = 130 girls, n = 123 boys; aged 18 months to 5 years) from 241 families participating in the Guelph Family Health Study were included in the analyses. Parents reported levels of parenting distress, depressive symptoms, household chaos, and family functioning. The inflammatory potential of parents’ and children’s diets was quantified using the Dietary Inflammatory Index (DII®), adjusted for total energy intake (i.e., the E-DIITM). E-DII scores were regressed onto family stress using generalized estimating equations to account for shared variance among family clusters. Compared to those in homes with low chaos, parents in chaotic homes had significantly more proinflammatory dietary profiles (β = 0.973; 95% CI: 0.321, 1.624, p = 0.003). Similarly, compared to those in well-functioning families, parents in dysfunctional families had significantly more proinflammatory dietary profiles (β = 0.967; 95% CI: 0.173, 1.761, p = 0.02). No significant associations were found between parents’ E-DII scores and parenting distress or depressive symptoms, nor were any associations found for children’s E-DII scores. Results were not found to differ between males and females. Parents in chaotic or dysfunctional family environments may be at increased risk of chronic disease due to proinflammatory dietary profiles. Children’s dietary inflammatory profiles were not directly associated with family stress; however, indirect connections through family food-related behaviours may exist. Future research should prioritize elucidating these mechanisms. 相似文献
88.
89.
Robison Valerie Bauman Brenda D’Angelo Denise V. Espinoza Lorena Thornton-Evans Gina Lin Mei 《Maternal and child health journal》2021,25(5):832-840
Maternal and Child Health Journal - To measure the association between dental and medical insurance with the receipt of dental cleaning during pregnancy. We analyzed Pregnancy Risk Assessment... 相似文献
90.
Valerie Kay Charles Livingstone 《Australian and New Zealand journal of public health》2021,45(1):71-79
Objective : To analyse a ‘socioecological’ health promotion discourse and its relationship to orthodox ‘economistic’ discourse in Australia. Method : In research on health promotion addressing equity and environmental sustainability, we identified a socioecological discourse, based on an ethic of care for people and ecosystems. Using Foucault's concept of discourse as a regime that produces and legitimises certain kinds of knowledge, and ecofeminist historical analysis, we analysed this discourse and its relationship to economism. Results : The socioecological discourse takes social and ecological wellbeing as primary values, while economism takes production and trade of goods and services, measured by money, as primary. Following British invasion, property‐owning white men in Australia had the right to control and profit from land, trade, and the work of women and subordinate peoples. A knowledge regime using money as a primary measure reflects this history. In contrast, a First Nations’ primary value expressed in the study was ‘look after the land and the children’. Conclusion and implications for public health : Public health often attempts to express value through economism, using monetary measures. However, socioecological discourse, expressed for example through direct measures of social and ecological wellbeing, appears more fit for purpose in promoting a fair and sustainable society. 相似文献