728 research outputs found

    Autonomous control of terminal erythropoiesis via physical interactions among erythroid cells

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    AbstractIn vitro erythropoiesis has been studied extensively for its application in the manufacture of transfusable erythrocytes. Unfortunately, culture conditions have not been as effective as in vivo growth conditions, where bone marrow macrophages are known to be a key regulator of erythropoiesis. This study focused on the fact that some erythroblasts are detached from macrophages and only contact other erythroblasts. We hypothesized that additional factors regulate erythroblasts, likely through either physical contact or secreted factors. To further elucidate these critical factors, human erythroblasts derived from cord blood were cultured at high density to mimic marrow conditions. This growth condition resulted in a significantly increased erythroid enucleation rate and viability. We found several novel contact-related signals in erythroblasts: intercellular adhesion molecule-4 (ICAM-4) and deleted in liver cancer-1 (DLC-1). DLC-1, a Rho-GTPase-activating protein, has not previously been reported in erythroid cells, but its interaction with ICAM-4 was demonstrated here. We further confirmed the presence of a secreted form of human ICAM-4 for the first time. When soluble ICAM-4 was added to media, cell viability and enucleation increased with decreased nuclear dysplasia, suggesting that ICAM-4 is a key factor in contact between cells. These results highlight potential new mechanisms for autonomous control of erythropoiesis. The application of these procedures to erythrocyte manufacturing could enhance in vitro erythrocyte production for clinical use

    The effect of a culturally tailored web-based physical activity promotion program on Asian American midlife women’s depressive symptoms

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    The benefits of physical activities on depressive symptoms have increasingly been reported in the literature, but the effect through which a Web-based physical activity promotion program alleviates depressive symptoms is not clearly known, especially among ethnic minority midlife women. The purpose of this pilot randomized control study is to examine the preliminary efficacy of the Web-based physical activity promotion program in enhancing the depressive symptoms of Asian American midlife women through increasing physical activity. This study adopted a randomized repeated measures pretest/posttest control group design. This study consisted of two groups of research participants: 18 in an intervention group and 15 in a control group. By using multiple instruments, the participants’ background and health status, depressive symptom experience, and physical activity experience were measured at three time points (pre-, post 1-month, and post 3-months). The data were analyzed using a modified intent-to-treat linear mixed-model growth curve analysis. After controlling for covariates, random intercept, and random slope, only discrimination stress showed statistical significances in the group effect (0.18, p = .08 for control) and time effect (-0.04, p = .04), but not in the group × time effect (p = .51). The active living habits scores showed statistical significances in the group effect (0.82, p \u3c 0.01 for control), time effect (0.29, p \u3c 0.01), and group × time effect (-0.31, p = 0.03 for control). Findings support the significant effect of the Web-based physical activity promotion program on the women’s discrimination stress and active living habits

    Accelerated Ulcer Healing and Resistance to Ulcer Recurrence with Gastroprotectants in Rat Model of Acetic Acid-induced Gastric Ulcer

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    Quality of ulcer healing (QOUH) is defined as ideal ulcer healing featuring with the fine granular ulcer scar, high functional restoration and the resistance to recurrence. This study was designed to compare the rates of QOUH achievement in rat gastric ulcer model between acid suppressant treated group and gastroprotectant treated group accompanied with elucidations of molecular mechanisms. Serosal injection of acetic acids for generating gastric ulcer and intraperitoneal (ip) injection of recombinant interleukin 1-beta (IL-1β) for recurring healed ulcer was done in SD rats. The 72 rats were divided into three groups according to treatment as follows; Group I, no further treatment, Group II, 8 weeks treatment of omeprazole, and Group III, 8 weeks of gastroprotectant treatment. IL-1β was administered for ulcer recurrence after 28 weeks of acetic acid injection. At four weeks after gastric ulcerogenesis, 58.3% (7/12) of active gastric ulcer were converted to healing stage in Group III, but 16.7% (2/12) in Group II and none in Group I, for which significant levels of epidermal growth factor, mucin, and pS2/trefoil peptide1 were contributive to these accelerated healings of Group III. ip injections of rIL-1β (200 µg/kg) at 28 weeks after acetic acid injection led to 100% of ulcer recurrence in Group I and 75.0% in Group II, but only 16.7% of Group III rats showed ulcer recurrence. Significantly attenuated levels of inflammatory cytokines including IL-2, transforming growth factor-alpha (TNF-α), cyclooxygenase-2 (COX-2), nitrotyrosine were responsible for the resistance to ulcer recurrence in Group III. Conclusively, gastroprotectant might be prerequisite in order to achieve ideal QOUH through significant inductions of remodeling

    Self-assembled adipose-derived mesenchymal stem cells as an extracellular matrix component- and growth factor-enriched filler

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    The clinical application of mesenchymal stem cells (MSCs) is attracting attention due to their excellent safety, convenient acquisition, multipotency, and trophic activity. The clinical effectiveness of transplanted MSCs is well-known in regenerative and immunomodulatory medicine, but there is a demand for their improved viability and regenerative function after transplantation. In this study, we isolated MSCs from adipose tissue from three human donors and generated uniformly sized MSC spheroids (∼100 µm in diameter) called microblocks (MiBs) for dermal reconstitution. The viability and MSC marker expression of MSCs in MiBs were similar to those of monolayer MSCs. Compared with monolayer MSCs, MiBs produced more extracellular matrix (ECM) components, including type I collagen, fibronectin, and hyaluronic acid, and growth factors such as vascular endothelial growth factor and hepatocyte growth factor. Subcutaneously injected MiBs showed skin volume retaining capacity in mice. These results indicate that MiBs could be applied as regenerative medicine for skin conditions such as atrophic scar by having high ECM and bioactive factor expression

    Carcinoma Mixed within Milk of Calcium in a Breast: a Case Report

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    Milk of calcium located in the breast is typically a benign entity. However, carcinoma may incidentally arise adjacent to or even within milk of calcium. Consequently, the characteristics of all observed calcific particles should be carefully analyzed. In this study, we report a case of carcinoma presented as malignant microcalcifications mixed within milk of calcium in a breast
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