Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The marrow of a dog affected with cyclic neutropenia (CN) was transplanted into an unaffected supralethally irradiated litermate. Prompt engraftment occurred, and cyclic rises and falls in numbers of platelets, reticulocytes, and granulocytes were noted in the recipient soon after engraftment. Prior to transplantation and under hypoxic conditions, the donor had serum erythropoietin (ESF) peak levels at 11-12-day intervals. Following transplatation and under hypoxic conditions, cyclic peaks of ESF occurred in the transplanted dog.
 ...
PMID:Canine cyclic neutropenia: Erythropoietin and platelet cycles after bone marrow transplantation. 4 49

Following extensive bowel resection, a young woman experienced severe malnutrition; subsequent administration of parenteral nutrition precipitated the copper deficiency syndrome. This consisted of hypocupremia, subnormal ceruloplasmin levels, anemia, and severe neutropenia. The bone marrow was megaloblastic, vacuolated, and sideroblastic; granulocytic maturation was not observed beyond the myelocyte stage. Copper sulfate therapy was followed by a marked reticulocytosis, increase in hematocrit, and recovery of neutrophils. Additional studies indicated that both serum and urinary erythropoietin values were low; serum activity increased after copper supplementation. Abnormal granulopoiesis was demonstrated using the in vitro granulocyte colony assay. The patient's granulcoytic stem cells were normal on two occasions; however, mixing studies showed that culture of the patient's copper-deficient marrow with her copper-deficient serum yielded significantly reduced numbers of granulocyte colonies. Thus, copper appears to be a necessary element for normal hematopoiesis; lack of this trace element may result in ineffective erythropoiesis and granulopoiesis.
 ...
PMID:Observations on the anemia and neutropenia of human copper deficiency. 30 69

Studies were done of cell production by marrow in diffusion chambers implanted in the peritoneal cavity of rabbits subjected to various stimuli to hematopoiesis. In chambers in neutropenic hosts and in hosts injected with endotoxin, animals presumed to have an increased stimulus to granulopoiesis, there was increased production of granulocytes but there was also increased production of red cells. Although red cell production was decreased in chambers in polycythemic hosts, granulocyte production was not different from that in controls. Stimulation of erythropoiesis by erythropoietin injections or by exposure to hypoxia increased red cell production by marrow in the implanted diffusion chambers without diminishing granulopoiesis. Only in chambers in hosts made anemic by bleeding was there an increase in red cell production accompanied by a decrease in granulocyte production. In these anemic hosts induction of neutropenia led to an increase in granulopoiesis without any depression of erythropoiesis.
 ...
PMID:Marrow culture in diffusion chambers in rabbits. II. Effect of competing demands for red cell and white cell production on cell growth. 64 17

Nine patients with anorexia nervosa were studied, who had varying degrees of bone marrow failure ranging from a slight neutropenia to severe pancytopenia. In addition to routine laboratory work bone marrow biopsies were performed at admission and during the course of disease. In four of those patients erythropoietin excretion per 24 hours was measured by the bioassay in the polycythemic mouse at least twice during the course of treatment. At admission most bone marrow showed a marked although varying hypocellularity with grossly apparant background gelatinous material, which appeared to consist of acid mucopolysaccharides. Leukopenia and the changes of the bone marrow morphology reversed to normal after refeeding. Erythropoietin excretion was only elevated in patients who were anemic and returned to normal when the haematocrit reached normal levels. It seems therefore unlikely that an impaired production of erythropoietin or other postulated humoral factors cause the haemopoietic changes in anorexia nervosa. A direct effect of fat or carbohydrate depletion and/or of the increased mucopolysaccharides upon the proliferation of the haemopoietic cells can be suggested, but is an entirely speculative preposition.
 ...
PMID:[Haematological features of anorexia nervosa (author's transl)]. 90 49

Urinary and serum colony-stimulating factor (CSF) levels were measured in 11 patients with chronic idiopathic neutropenia without infections and in 10 normal individuals. Urinary CSF output was determined using mouse marrow target cells, and serum CSF activity was assayed with human marrow target cells by the double agar layer technique. Using these methods, there was no significant difference between CSF levels of neutropenic and normal subjects. These data indicate that CSF levels are not inversely related to the blood neutrophil count in chronic idiopathic neutropenia and suggest that CSF is not a hormone regulating the blood neutrophil count in a manner analogous to the erythropoietin regulation of circulating erythrocyte levels.
 ...
PMID:Colony-stimulating factor in patients with chronic neutropenia. 108 65

The results of erythropoietin (ESF) studies in dogs with cyclic haematopoiesis are presented. Even though the dogs were exposed to a constant stimulus of hypoxia, cycles in the plasma ESF levels occurred at 11 to 12 day intervals. In some dogs, minor midcycle peaks were observed and the amount of ESF produced varied with the different animals. The peaks of ESF characteristically appeared approximately five days after onset of neutropenia. A hypothesis is presented to explain the known facts concerning canine cyclic haematopoiesis. It suggests that a poietin controlling factor is produced and that this assumed factor then stimulates the production of specific factors leading to increases of reticulocytes, platelets, and monocytes. The monocytes in turn produce more colony stimulating factor (CSF) leading to the formation of granulocytes. Such a sequence of events would explain the apogee of reticulocyte, platelet, and monocyte counts at a time when the nadir of granulocyte counts is reached.
 ...
PMID:Hormonal control of erythropoiesis in canine cyclic haematopoiesis. 125 Nov 40

A transient hyporegenerative neutropenia has been reported in neonates, but not in older children or adults, undergoing treatment with recombinant erythropoietin (epo). Monocytopenia has not been reported. We postulated that epo might selectively reduce the responsiveness of neonatal progenitors to Granulocyte Colony-Stimulating Factor (G-CSF), while not similarly affecting their responsiveness to Macrophage Colony-Stimulating Factor (M-CSF). To test this hypothesis two types of experiments were performed. First, progenitors of adult or fetal origin were pre-incubated with epo (or control), then washed, and their responsiveness to G-CSF and M-CSF evaluated in clonogenic culture assays. Second, clonogenic maturation was initiated using either G-CSF or M-CSF, after which the effect of a late addition of epo to the developing clones was evaluated. Indeed, pre-incubation with epo resulted in production of fewer neutrophils from fetal progenitors grown in G-CSF (P less than 0.001), but it did not reduce the number of macrophages generated from progenitors grown in M-CSF. Adding epo to the already-developing G-CSF-responsive and M-CSF-responsive adult and fetal clones did not alter colony development. Thus, epo appears to have an action on G-CSF-responsive, but not-M-CSF-responsive fetal progenitors, resulting in reduced production of neutrophils. This effect is no longer apparent, however, when progenitors have matured to the 8-cell clone stage.
 ...
PMID:Erythropoietin affects the maturation pattern of fetal G-CSF-responsive progenitors. 137 65

Anemia and neutropenia are common complications of HIV infection. Antiretroviral therapy with zidovudine exacerbates bone marrow suppression by inhibiting proliferation of blood cell progenitor cells. In addition, treatment for opportunistic infections or malignancies can involve the use of myelosuppressive drugs. As a consequence, severe anemia and neutropenia can result, thereby limiting the utilization of antiretroviral drugs. Since antiretroviral therapy can increase survival, drugs that ameliorate myelosuppression are important adjuncts in the treatment of HIV-infected patients. Three hematopoietic growth factors are effective in the treatment of anemia or neutropenia. In four placebo-controlled trials, erythropoietin (EPO) at doses up to 600 U/kg/wk decreased mean transfusion requirements by 37%, increased mean hematocrit by 4.5% and corrected anemia in the majority of patients receiving zidovudine over a 12-week period. In a separate study, granulocyte colony-stimulating factor (G-CSF) corrected leukopenia and isolated neutrophil defects in 22 patients with AIDS without altering HIV expression. When erythropoietin was added to the regimen, combined G-CSF and EPO corrected both anemia and leukopenia and lessened subsequent zidovudine toxicity. Similarly, granulocyte macrophage-colony-stimulating factor (GM-CSF) corrected leukopenia and pre-existing neutrophil defects in patients with HIV infection. In controlled and uncontrolled trials, GM-CSF also appears to reduce toxicity from zidovudine, ganciclovir, and antineoplastic therapy. New combinations of hematopoietic stimulants are being used to decrease the toxicity from combination antiretroviral therapy with alpha interferon and cytotoxic chemotherapy in the treatment of AIDS-related malignancies.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Hematopoietic growth factors as adjuncts to antiretroviral therapy. 138 Feb 56

Recently biotechnologic progress has, through the technique of the recombinant DNA, allowed a low cost production of large amount of several growth factors. Such a large availability has made possible to either carry out deeper investigations on the physiopathology of the hemopoietic regulation and perform new therapeutic approaches under different pathologic conditions. The most interesting acquisition concerning the biology of hemopoiesis to which such investigations have addressed us is the inadequacy of the protocols adopted till now. Such protocols considered only a simple vision of an elective action of a given growth factor during an exact maturation period of a determined cell colony. On the contrary, it was possible to point out a close network of inter-relationship among the different factors, which sometime impedes a clear distinction for each single factor, between actions of competence and progression in the cell maturation phenomena. However, the present uncertainty pertaining to the regulation of hemopoiesis has not impede the performance of clinical trials with positive findings in several pathologic conditions. The administration of recombinant erythropoietin has for example allowed to intervene in a resolutive way on the anemia in uremic subjects, and seems giving satisfactory results also in subjects with non renal origin anemic conditions. Satisfactory results were also obtained through the use of the Granulocyte-Macrophage CSF and of the Granulocyte-CSF, which by preventing neutropenia have allowed the performance of more adequate chemotherapeutic protocols in neoplastic subjects. New interesting perspectives are now coming for the use of Interleukin-3 in the treatment of the aplastic anaemia.
 ...
PMID:[Growth factors and hematopoiesis. Physiopathology and clinical applications]. 138 4

Recent reports of neutropenia associated with the use of recombinant human erythropoietin (r-HuEpo) in preterm infants with the anaemia of prematurity have raised concern over the clinical use of this hormone. The present studies were undertaken to determine whether high-dose r-HuEpo has an effect on granulocyte production in vitro. The studies used a serum deprived, optimized semi-solid cell culture system to investigate the effect of lineage specific and non-specific granulocyte and erythroid colony stimulating factors on circulating peripheral blood granulocyte-macrophage colony forming units (CFU-GM), erythroid burst forming units (BFU-E) and multilineage colonies (CFU-Mix) from nine premature infants and seven healthy adults. CFU-GM were grown in the presence of interleukin 3 (IL3) 8 ng/ml, granulocyte-macrophage colony stimulating factor (GM-CSF) 20 ng/ml and granulocyte colony stimulating factor (G-CSF) 15 ng/ml alone and combinations of G-CSF with GM-CSF or IL3. The number, size and differentiation of CFU-GM colonies were then analysed in the presence and absence of high dose r-HuEpo (4 U/ml). High-dose r-HuEpo did not exert any significant modulatory effects on the number of CFU-GM colonies produced in the presence of IL3, GM-CSF and G-CSF alone or in combination. The number of cells within each CFU-GM colony did not change significantly, nor was there a significant change in the degree of differentiation. The combined number of BFU-E, CFU-GM and CFU-Mix colonies increased with r-HuEpo in both adults (1.8 x) and preterm infants (1.4 x), almost exclusively due to an increase in BFU-E derived colonies. Thus, no evidence was found for an r-HuEpo mediated redirection of multipotential haemopoietic stem cells into committed erythroid precursors at the expense of myeloid precursors.
 ...
PMID:The in vitro effect of high-dose recombinant human erythropoietin on granulocyte-macrophage colony production in premature infants using a defined serum deprived cell culture system. 138 42


1 2 3 4 5 6 7 8 9 10 Next >>