Results 1 - 10 of 1951
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[en] Intrathoracic extramedullary hematopoiesis (EMH) is a rare condition of the hereditary spherocytosis. EMH usually regresses or disappears after treatment; such as splenectomy in the case of spherocytosis. We report a case of hereditary spherocytosis. It is presented with an unilateral paravertebral posterior mediastinal mass. After splenectomy, it revealed shrinkage and fatty replacement on serial CT scans.
[en] A case of β-thalassemia intermedia with spinal cord compression due to extramedullary hematopoiesis, which was successfully treated by blood transfusion, is presented. Emphasis was made on the MRI appearance of extramedullary hematopoiesis on different pulse sequences. The theories that aimed to explain the involvement of the epidural space by extramedullary hematopoiesis are discussed
[en] RUNX1 is a member of RUNX transcription factors and plays important roles in hematopoiesis. RUNX1 function is under the tight control through posttranslational modifications, including phosphorylation and ubiquitination. We previously developed a luminescence-based binding assay (AlphaScreen) to systematically detect RUNX1-interacting E3 ubiquitin ligases. In this study, we showed that a nuclear ubiquitin ligase RNF38 induced ubiquitination of RUNX1. RNF38-induced RUNX1 ubiquitination did not promote RUNX1 degradation, but rather stabilized RUNX1 protein. We also found that RNF38 enhanced RUNX1-mediated transcriptional repression of the erythroid master regulator KLF1 in K562 cells. Consequently, RNF38 cooperated with RUNX1 to inhibit erythroid differentiation of K562 cells. Thus, our study identified RNF38 as a novel E3 ligase that modifies RUNX1 function without inducing its degradation.
[en] The production of CSF (Colony Stimulating Factor) by leukocytes of normal subjects and subjects with CML (Chronic Myeloid Leukemia) were compared, using the following technics: leukocytes separation, measurement of CSF activity. The results have shown that blood leukocyte stimulating activity of subjects with CLM is lower than in normal subjects
[fr]On a compare la production de CSF (Colony Stimulating Factor) par les leucocytes du sang peripherique de sujets normaux et de sujets atteints de LMC, a l'aide des techniques suivantes: separation des leucocytes; dosage de l'activite CSF des fractions obtenues. Les resultats ont montre que l'activite stimulante des leucocytes du sang peripherique de sujets atteints de LMC est tres inferieure a celle que l'on observe chez les sujets normaux
[en] Highlights: • IAHCs of E10.5 AGM co-express SOX17 and NOTCH1. • SOX17 directly binds to the Notch1 promoter and induces Notch1 expression. • Notch1- and Hes1-transduced HSCs and HPCs maintain their undifferentiated states. The aorta-gonad-mesonephros region, from which definitive hematopoiesis first arises in midgestation mouse embryos, has intra-aortic hematopoietic clusters (IAHCs) containing hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs). We previously reported expression of the transcription factor Sox17 in IAHCs, and overexpression of Sox17 in CD45lowc-KIThigh cells comprising IAHCs maintains the formation of cell clusters and their multipotency in vitro over multiple passages. Here, we demonstrate the importance of NOTCH1 in IAHC formation and maintenance of the HSC/HPC phenotype. We further show that Notch1 expression is positively regulated by SOX17 via direct binding to its gene promoter. SOX17 and NOTCH1 were both found to be expressed in vivo in cells of IAHCs by whole mount immunostaining. We found that cells transduced with the active form of NOTCH1 or its downstream target, Hes1, maintained their multipotent colony-forming capacity in semisolid medium. Moreover, cells stimulated by NOTCH1 ligand, Jagged1, or Delta-like protein 1, had the capacity to form multilineage colonies. Conversely, knockdown of Notch1 and Hes1 led to a reduction of their multipotent colony-forming capacity. These results suggest that the Sox17-Notch1-Hes1 pathway is critical for maintaining the undifferentiated state of IAHCs.
[en] Perturbation of hematopoiesis is a life-threatening consequence of an exposure to ionizing radiation in situations of nuclear accidents, contingent terrorist attacks, or possible war using nuclear weapons. Search for drugs which would alleviate radiation-induced myelosuppression is a long term task for laboratories focusing their activities on pharmacological modulation of radiation damage. The hypothesis about contingent stimulatory effects of pharmacological activation of adenosine membrane receptors on radiation-suppressed hematopoiesis has been originally postulated in the laboratory of the authors. Beneficial effects of drugs elevating extracellular adenosine, i.e. of a combination of adenosine monophosphate, an adenosine prodrug, and dipyridamole, which prevents the cellular uptake of adenosine, have been found when the drugs were administered either before or after irradiation with a single dose, as well as when given repeatedly in the course of repeated irradiation. Elevated extracellular adenosine has been also observed to potentiate hematopoiesis-stimulating effects of granulocyte colony-stimulating factor. Recently attention of the authors has been focused on testing the hematopoiesis-modulating effects of synthetic agonists of adenosine receptors, more or less selective for individual adenosine receptor subtypes. Whereas the agonist of adenosine A1 receptors, CPA, has been found to suppress the proliferation of hematopoietic progenitor and precursor cells, the adenosine A3 receptor agonist, IB-MECA, has been observed to possess significant pro-stimulatory activity. These results strongly suggest that pharmacological activation of adenosine membrane receptors might find its use in the treatment of radiation-induced myelosuppression. (author)
[en] In this study, we aimed to elucidate the detailed structure and active moiety of polysaccharide, one of the active constituents of immune and hematopoietic modulating activities of HemoHIM. We first isolated the polysaccharide fractions from the hot water extracts of the each ingredient herbs (A. gigas, P. janonica, C. officinale) of HemoHIM and their mixture. These polysaccharides were composed of neutral (85.32-92.73%) and acidic (4.25-7.88%) saccharides, proteins (0.16-4.02%), and polyphenols (2.09-5.37%). The hydrolytic analysis of polysaccharide fractions showed that they commonly showed higher arabinose, galactose, and galacturonic acid contents. These result suggested that these polysaccharides may have higher contents of rhamnogalacturonan among pectic substances and the main active moiety is composed of polysaccharides. The anion exchange chromatography of HemoHIM and each ingredient herb extract using DEAE-Sepharose FF (Cl- form) column resulted in 1 non-adsorption and 8 adsorption fractions. The analysis of immune activity (lymphocyte proliferation) on these fractions showed that the fractions obtained by higher salt concentration carried the higher activity, but all fractions showed considerable immune activity
[en] Highlights: • Rheb deficiency causes abnormalities in myeloid lineage cells. • Rheb deficiency impairs HSC-derived hematopoiesis post-transplantation. • Unlike Raptor, Rheb is dispensable for HSC self-renewal at steady-state. The mammalian target of rapamycin (mTOR) complex 1 (mTORC1) senses a cell's energy status and environmental levels of nutrients and growth factors. In response, mTORC1 mediates signaling that controls protein translation and cellular metabolism. Although mTORC1 plays a critical role in hematopoiesis, it remains unclear which upstream stimuli regulate mTORC1 activity in the context of hematopoietic stem cells (HSC) maintenance in vivo. In this study, we investigated the function of Rheb, a critical regulator of mTORC1 activity controlled by the PI3K-AKT-TSC axis, both in HSC maintenance in mice at steady-state and in HSC-derived hematopoiesis post-transplantation. In contrast to the severe hematopoietic dysfunction caused by Raptor deletion, which completely inactivates mTORC1, Rheb deficiency in adult mice did not show remarkable hematopoietic failure. Lack of Rheb caused abnormalities in myeloid cells but did not have impact on hematopoietic regeneration in mice subjected to injury by irradiation. As previously reported, Rheb deficiency resulted in defective HSC-derived hematopoiesis post-transplantation. However, while Raptor is essential for HSC competitiveness in vivo, Rheb is dispensable for HSC maintenance under physiological conditions, indicating that the PI3K-AKT-TSC pathway does not contribute to mTORC1 activity for sustaining HSC self-renewal activity at steady-state. Thus, the various regulatory elements that impinge upstream of mTORC1 activation pathways are differentially required for HSC homeostasis in vivo.
[en] We performed a clinical study to evaluate the immune promotion and antioxidant effects of the developed product (HemoHIM) in healthy or subhealthy people. Volunteers with white blood cell numbers between 5000 and 10000/ul were recruited and the subjects were selected by appropriate inclusion and exclusion rules. The subjects were randomly assigned to 3 groups (HemoHIM 6g/day, HemoHIM 12g/day, Placebo). HemoHIM or placebo were adminstered for 2 months and the blood were collected and analyzed at 1 month and 2 month after the intake. The collected blood was analyzed for blood cell number, serum biochemical values (liver and kidney function), immunological activity of blood cells, antioxidant activity of blood plasma, and stress hormone level in the saliva. Finally the data of 88 subjects were analyzed for the immune promoting and antioxidant effects of HemoHIM. In results, no significant changes in blood cell numbers (white blood cell, lymphocyte, red blood cell) were observed in HemoHIM intake groups. However, NK cell activity were increased in HemoHIM intake groups and also IFN-γ and IL-12, the biomarkers of immune cell functions, were increased in proportion to the dose and intake periode of HemoHIM. The antioxidant biomarker (TAS) was not significantly changed by HemoHIM intake. Besides, the serum biochemical analysis for liver and kidney functions, and the general medical examination showed the HemoHIM showed no side-effects, thus reconfirming its safety in humans. In conclusion, this study showed HemoHIM has a significant effects on the promotion of immune functions, while it has neither side-effects nor toxicity in humans. The results of this study may be utilized for the scientific data to acquire the Health Functional Food Certification of HemoHIM from Korea FDA
[en] Fatal massive haemoptysis occured as a late complication of erosion of the pulmonary artery by a non-malignant ulcer of the left main bronchus. Symptoms attributed to radiation pulmonary fibrosis are uncommon. We report a case of fatal massive haemoptysis in a patient known to have postirradiation pulmonary fibrosis. (author)