Adult ; Adult Stem Cells ; Humans ; Research ; trends

Erythropoietin (EPO) is an acidic glycoprotein that was first detected as a hematopoietic factor and its synthesis is triggered in response to cellular hypoxia-sensing. EPO binds to type I cytokine receptors, which associate with the non-receptor tyrosine kinase Jak2, and thereby activate Stat 5a/5b, Ras/MAPK, and PI3-K/Akt signaling pathways. The recent discovery shows that there is a specific EPO/EPO-receptor system in the central nervous system (CNS), independently of the haematopoietic system. Hypoxia and anemia can up-regulate EPO/EPOR expressions in the CNS. Further studies demonstrate that EPO has substantial neuro-protective effects and acts as a neurotrophic factor on central cholinergic neurons, influencing their differentiation and regeneration. EPO also exerts neuro-protective activities in different models of brain damage in vivo and in vitro, such as hypoxia, cerebral ischaemia and sub-arachnoid haemorrhage. EPO may also be involved in synaptic plasticity via the inhibition or stimulation of various neurotransmitters. Therefore, human recombinant EPO that activate its receptors in the central nervous system might be utilized in the future clinical practice involving neuroprotection and brain repair.
Animals ; Brain ; metabolism ; Cell Differentiation ; drug effects ; Erythropoietin ; metabolism ; pharmacology ; Humans ; Neurons ; cytology ; drug effects ; Neuroprotective Agents ; metabolism ; pharmacology ; Receptors, Erythropoietin ; metabolism

Severe acute respiratory syndrome (SARS) has recently recognized as a new human infectious disease. A novel coronavirus was identified as the causative agent of SARS. This report summarizes the hematological findings in SARS patients and proposes a hypothesis for the pathophysiology of SARS coronavirus related abnormal hematopoiesis. Hematological changes in patients with SARS were common and included lymphopenia (68% - 90% of adults; 100% of children, n = 10), thrombocytopenia (20% - 45% of adults, 50% of children), and leukopenia (20% - 34% of adults, 70% of children). The possible mechanisms of this coronavirus on blood system may include (1) directly infect blood cells and bone marrow stromal cells via CD13 or CD66a; and/or (2) induce auto-antibodies and immune complexes to damage these cells. In addition, lung damage in SARS patients may also play a role on inducing thrombocytopenia by (1) increasing the consumption of platelets/megakaryocytes; and/or (2) reducing the production of platelets in the lungs. Since the most common hematological changes in SARS patients were lymphopenia and immunodeficiency. We postulate that hematopoietic growth factors such as G-CSF, by mobilizing endogenous blood stem cells and endogenous cytokines, could become a hematological treatment for SARS patients, which may enhance the immune system against these virus.
Adult ; Antigens, CD ; immunology ; Antigens, Differentiation ; immunology ; CD13 Antigens ; immunology ; Cell Adhesion Molecules ; Child ; Hematologic Diseases ; immunology ; physiopathology ; Hematopoiesis ; physiology ; Humans ; SARS Virus ; Severe Acute Respiratory Syndrome ; immunology ; physiopathology ; virology

The immunological role of megakaryocytes is not well known. This project studies the involvement of megakaryocytes on immuno-inflammatory processes and the possible mechanism via the adhesion molecule CD36 and the synthesis of relevant cytokines. The expression of adhesion protein CD36 on human platelets, megakaryocytes and megakaryocytic cell lines (Meg-01, Dami, CHRF-288-11 and M-07e) was analyzed by using flow cytometry, ELISA and immunocytochemical methods. The expression of interleukin-1 (IL-1) to interleukin-10 (IL-10), TNF-alpha, TNF-gamma and IFN-gamma on the four megakaryocytic cell lines was also determined by RT-PCR. The effect of IL-1beta, IL-3, IL-6 and TPO on murine megakaryocyte colony formation (CFU-MK) was studied by using a plasma clot culture system. The CFU-MK was confirmed by acetylcholine esterase staining. The results showed that: (1) CD36 was expressed on platelets, megakaryocytes and the four megakaryocytic cell lines, the relative expression level is as follows: platelets > megakaryocytes > Meg-01 > Dami > CHRF-288-11 > M-07e, suggesting that the level of CD36 expression correlates with the degree of maturity of megakaryocytic differentiation; (2) inflammatory cytokines TNF-alpha, IL-1beta, IL-3 and IL-6 were detected in all the four megakaryocytic cell lines, suggesting that different stages of megakaryocytes can be as a source of inflammatory cytokines; and (3) IL-1beta, IL-3 and IL-6, as well as TPO, play a stimulating effect on CFU-MK formation, suggesting that there is an "autocrine" effect on megakaryocytopoiesis. The data obtained suggest that megakaryocytes may involve in immuno-inflammatory processes via the synthesis of platelet adhesion molecules and inflammatory cytokines.

To identify the expression of thrombopoietin (TPO) receptors (c-mpl) on central nervous system (CNS) and to evaluate the role of TPO on neural cell proliferation and protection, immunohistochemical staining, RT-PCR, MTT, and annexin-V methods were used in this study. The results showed the expression of TPO receptor on human CNS and murine neural cells. C-mpl mRNA was identified in human cerebral hemispheres and cerebellum, and mouse neural cell line C17.2 by RT-PCR. C-mpl was also confirmed in human cerebral hemispheres by immunohistostaining with con-focal microscopy. Furthermore, TPO had a stimulating effect on the growth of in vitro neural cell C17.2 by MTT assay. The anti-apoptotic effect of TPO on C17.2 cells was also demonstrated by staining with annexin-V and PI. In conclusion, the first evidence showed the expression of TPO receptor c-mpl in central nervous system. Moreover, the effect of TPO on neural cell proliferation and anti-apoptosis was also demonstrated on in vitro neural cells.
Animals ; Apoptosis ; drug effects ; Brain Chemistry ; Cell Line ; Cell Proliferation ; drug effects ; Erythropoietin ; pharmacology ; Humans ; Mice ; Neoplasm Proteins ; analysis ; Neurons ; drug effects ; Oncogene Proteins ; analysis ; Proto-Oncogene Proteins ; analysis ; Receptors, Cytokine ; analysis ; Receptors, Thrombopoietin ; Thrombopoietin ; pharmacology

Child ; Dystonia Musculorum Deformans ; diagnostic imaging ; drug therapy ; genetics ; Female ; Humans ; Male ; Molecular Chaperones ; genetics ; Mutation ; Pedigree ; Positron-Emission Tomography

INTRODUCTIONTraditional Chinese medicine (TCM) has been used as an alternative in treating children with atopic dermatitis (AD) but its efficacy and potential side effects are debatable. We recently used a TCM capsule (PentaHerbs) on 9 children and observed significant reductions in clinical scores of disease severity. However, there have been concerns that the therapeutic effects of many forms of TCM are due to the presence of corticosteroids. The purpose of this study was to evaluate if common corticosteroids are present in PentaHerbs capsules.

MATERIALS AND METHODSPentaHerbs powder was analysed with thin-layer chromatography, infra-red spectrophotometry and liquid chromatography mass spectrometry.

RESULTSHydrocortisone, prednisolone, fludrocortisone and dexamethasone were not detected in the PentaHerbs capsules.

CONCLUSIONCorticosteroids are not present in the 5 familiar herbs that were earlier shown to have efficacy on AD.

Child ; Chromatography, Thin Layer ; Dermatitis, Atopic ; drug therapy ; Drug Combinations ; Drugs, Chinese Herbal ; chemistry ; therapeutic use ; Glucocorticoids ; analysis ; therapeutic use ; Humans ; Mass Spectrometry ; Pilot Projects ; Spectrophotometry, Infrared