Hematopoesis

This study investigated the effects of cadmium (Cd) and monensin on spleen function in mice, subjected to subacute Cd-intoxication. Adult male ICR mice were divided into three groups (n = 6 per group) as follows: control group (received distilled water and food ad libitum); Cd-treated (20 mg/kg/b.w./day Cd(II) acetate for the first 2 weeks of the experimental protocol); monensin-treated mice (20 mg/kg/day Cd(II) acetate for the first 2 weeks followed by treatment with 16 mg/kg b.w./day monensin from days 15 to 28...

The cytokine erythropoietin (EPO) is an important regulator of hematopoesis and has well-known tissue protective properties. Neurotrophic action is implicated as mechanistically important in the treatment of depression, and neurotrophic actions of EPO suggest potential therapeutic utility of an EPO-like mechanism in depressive disorder. Rodent behavioral models that are responsive to clinically used antidepressants as well as to neurotrophic compounds can be used to assess potential antidepressant properties of EPO and EPO-like compounds...

CASE DESCRIPTION: An 11-year-old spayed female Siberian Husky was evaluated because of a 2-week history of progressive paraparesis. CLINICAL FINDINGS: Results of neurologic examination were consistent with a T3-L3 myelopathy. There were no abnormalities on CBC, and hypercalcemia was noted on serum biochemical analysis. Several hypoechoic splenic nodules were evident on abdominal ultrasonography, and results of fine-needle aspiration cytology were consistent with splenic extramedullary hematopoiesis (EMH)...

Sickle cell disease is a common hematologic disorder with some uncommon clinical manifestations. While there are an abundance of described disease manifestations of the head and neck, extramedullary hematopoesis within the paranasal sinuses is exceedingly rare. Here, we present a case of a young boy with known sickle cell disease who presented to hospital with headaches of new onset. Imaging demonstrated an expansile mass lesion occupying the sphenoid sinus and on biopsy was found to be active hematopoetic bone marrow...

Myelodysplastic syndromes (MDS) comprise a heterogeneous group of diseases characterized by bone marrow failure, marrow dysplasia, and a tendency to evolve to acute leukemia. Pathophysiologically, low risk MDS are separated from the high risk category by an increased rate of apoptosis of the bone marrow cells which causes the morphological paradoxon of a peripheral cytopenia and hypercellular bone marrow known as ineffective hematopoesis. Laboratory findings and clinical evidence suggest that some patients with myelodysplastic syndrome have immunologically mediated disease...

RATIONALE: c-myb null (knockout) embryonic stem cells (ESC) can differentiate into cardiomyocytes but not contractile smooth muscle cells (SMC) in embryoid bodies (EB). OBJECTIVE: To define the role of c-Myb in SMC differentiation from ESC. METHODS AND RESULTS: In wild-type (WT) EB, high c-Myb levels on days 0-2 of differentiation undergo ubiquitin-mediated proteosomal degradation on days 2.5-3, resurging on days 4-6, without changing c-myb mRNA levels...

We report the case of a highly trained endurance athlete (22-year-old) who developed anemia (Hb 9.5 mg/dl) over a period of 6 months. Iron deficient or haemolytic anemia, as well as chronic loss of blood, were excluded. Further, laboratory analyses revealed that this athlete exhibited very low levels of testosterone due to a partial hypogonadotropic hypogonadism. Following testosterone supplementation, red blood cell indices improved. Although hypogonadotropic hypogonadism is well known to be associated with reduced hematopoesis, it rarely causes anemia in athletes...

Cytokines are essential regulators of hematopoesis and the immune system. Genetic engineering of recombinant cytokines has facilitated their implementation in many clinical areas. In the field of oncology the granulopoetic human growth factors G-CSF and GM-CSF are of particular importance. They can be applied to prevent chemotherapy induced neutropenia. Furthermore, they allow for mobilization of hematopoetic stem cells in order to obtain peripheral blood stem cell transplants. Another class of cytokines, the interferons, possess immunomodulating, antiproliferative, and antiviral properties...

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Bone morphogenetic proteins (BMPs) play a crucial role during embryonic development and regulate processes as diverse as neurogenesis, skeletal formation, and hematopoesis. They signal through a hetero-oligomer complex of BMP receptors. Binding of the ligand to the receptors activates several pathways, including Smad and p38. BMP signaling is controlled in the extracellular space, the plasma membrane, and the intracellular space; however, the mechanism of receptor signaling at the plasma membrane and proteins that regulate this process still need to be identified...

MYB is a leucine zipper transcription factor that is essential for hematopoesis and for renewal of colonic crypts. There is also ample evidence showing that MYB is leukemogenic in several animal species. However, it was not until recently that clear evidence was presented showing that MYB actually is an oncogene rearranged in human cancer. In a recent study, a novel mechanism of activation of MYB involving gene fusion was identified in carcinomas of the breast and head and neck. A t(6;9) translocation was shown to generate fusions between MYB and the transcription factor gene NFIB...

Human pluripotent stem cells (PSCs) derived from a number of different sources, including reprogrammed adult somatic cells, provide a powerful cellular system to study signaling pathways implicated in cell fate decisions, and generate new sources of cells for regenerative medicine. To realize this potential, it is essential to control the direction and efficiency of human PSC differentiation. Although Notch, Wnt and Hedgehog (HH) signaling pathways have been implicated in the self-renewal/proliferation of hematopoietic stem/progenitor cells, both in vitro and in vivo, their roles in differentiation processes remain poorly explored...

UNLABELLED: We report on the fatal clinical course of a 3 year old male Turkish patient suffering from osteopetrosis caused by a homozygous mutation in the chloride channel gene ClCN7 with developing pancytopenia and severe neurological impairment. Hepatosplenomegaly due to extramedullary hematopoesis, severe transfusion-dependent anemia and growth failure initially suggested metabolic or oncologic disorder. Particular haematological parameters like tear drop cells basophilic punctation of the polymorphonuclear cells in the absence of haemolysis caused the diagnostic X-ray investigations of the skull and vertebral column...

Chronic idiopathic myelofibrosis (CIM) with myeloid metaplasia is a myeloproliferative disorder characterized by leukoerythroblastosis, tear drop erythrocytes, extra-medullary hematopoesis (EMH), and varying degree of myelofibrosis. CIM, presenting as refractory ascites secondary to peritoneal hematopoesis, is extremely rare with only six adult cases reported in literature. This is a report of a child with CIM presenting as refractory ascites as a consequence of EMH in the peritoneum. The patient was treated with intermittent hydroxyurea with favorable response over 3 weeks...

Hypoxia-inducible transcription factor (HIF) is the master regulator of hypoxia-inducible genes involved in the mediation of survival and adaptive responses to insufficient oxygen availability, such as genes involved in hematopoesis, angiogenesis, iron transport, glucose utilization, resistance to oxidative stress, cell proliferation, survival and apoptosis, extracellular matrix homeostasis, and tumor progression. The stability of the HIFalpha subunit is regulated by oxygen-dependent prolyl 4-hydroxylation catalyzed by the HIF prolyl 4-hydroxylases (P4Hs)...

Adipose tissue has been viewed as the primary source of stored energy, but with the discovery of novel adipose tissue gene products, i.e., adipokines, another equally important role has emerged. Adipose tissue is a key endocrine organ involved in multiple processes, including glucose homeostasis, steroid production, immunoregulation, hematopoesis, and reproduction. The distribution of adipose tissue may also have a significant impact on reproductive function.

Leptin, also called the satiation hormone plays a key role in regulating body weight, energy intake, and expenditure. Leptin interacts with its receptors, mainly located in the hypothalamus. Moreover, there has been an increasing evidence that leptin exerts pleiotropic effects. Multiple peripheral effects of leptin have been recently described including synthesis of the various hormones, e.g., sexual hormones, thyroid hormones, and growth hormone, as well as regulation of blood pressure, reproduction, osteogenesis, hematopoesis, angiogenesis...

Natural Killer (NK) cells are powerful effectors of cytotoxicity against "stressed" cells. They also produce cytokines and chemokines to activate the adaptive immune response. Understanding NK cell development and maturation may have implications for cancer therapy and for immunity against infections. We hypothesized that Notch signaling, critical for hematopoesis, would be involved in NK cell development. The role of constitutively activated Notch1 (ICN) on NK cell maturation was studied using human umbilical cord blood (UCB) progenitors cultured on a murine embryonic liver stroma cell line (EL08-1D2) and human cytokines...

Lead (Pb) induces arterial hypertension in consequence of low exposures, which is not manifested by Pb toxic effects on the marrow, kidneys or other organs. Pb hypertensive effect, in the range of blood concentration from 10 to 40 microg/dl, has been evidenced by numerous experimental and population studies. However, the presence of significant correlation between blood lead level and systolic and/or diastolic blood pressure is not confirmed by some epidemiological studies. These discrepancies can be explained by the observation, that Pb-induced hypertension results rather from past than from current exposure, hence the arterial pressure values should be rather related to bone than to blood lead level...

The interaction of the chemokine receptor CXCR4 with its ligand CXCL12 is involved in many biological processes such as hematopoesis, migration of immune cells, as well as in cancer metastasis. CXCR4 also mediates the infection of T-cells with X4-tropic HIV functioning as a coreceptor for the viral envelope protein gp120. Here, we describe highly potent, selective CXCR4 inhibitors that block CXCR4/CXCL12 interactions in vitro and in vivo as well as the infection of target cells by X4-tropic HIV.