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Biomedical subjects

M Foote

Publications and source records attributed to M Foote.

18 recordsLinked to original sources

Evolutionary and preservational constraints on origins of biologic groups: divergence times of eutherian mammals.

Some molecular clock estimates of divergence times of taxonomic groups undergoing evolutionary radiation are much older than the groups' first observed fossil record. Mathematical models of branching evolution are used to estimate the maximal rate of fossil preservation consistent with a postulated missing history, given the sum of species durations implied by early origins under a range of species origination and extinction rates. The plausibility of postulated divergence times depends on origination, extinction, and preservation rates estimated from the fossil record. For eutherian mammals, this approach suggests that it is unlikely that many modern orders arose much earlier than their oldest fossil records.

Animals

Filgrastim restores interleukin-2 production in blood from patients with advanced human immunodeficiency virus infection.

Filgrastim induces lymphocytosis, including all T cell subsets, and increased ex vivo interleukin (IL)-2 release as well as lymphocyte proliferation. Since Filgrastim is increasingly used in patients with human immunodeficiency virus (HIV) infection, the effect of Filgrastim on ex vivo cytokine production was determined. Whole blood from 8 healthy volunteers, 5 high-risk volunteers, and 31 HIV-infected outpatients was assayed for cytokine production in response to endotoxin (LPS) or staphylococcal enterotoxin B (SEB) in the presence or absence of 100 ng/mL Filgrastim. LPS-inducible blood cytokine release of HIV-infected patients was not different from that of normal or high-risk volunteers. The suppressive effect of Filgrastim on LPS-inducible blood tumor necrosis factor-alpha and interferon-gamma formation in normal volunteers was not found in HIV-infected patients. Patients with advanced HIV infection showed reduced IL-2 and IL-4 release in the presence of SEB. In the presence of Filgrastim, IL-2 production was partially restored.

Adult

Clinical benefits of improving host defences with rHuG-CSF.

Recombinant human granulocyte colony-stimulating factor (rHuG-CSF) has been shown to stimulate the production and function of neutrophils in vitro and in vivo. Clinical studies in patients receiving myelosuppressive chemotherapy showed earlier neutrophil recovery, a reduction in infectious complications of neutropenia, and the use of fewer antibiotics. Its use has also been established for mitigating the infectious complications associated with severe chronic neutropenia (SCN). Data are emerging that neutropenia also contributes to the risk of infections in patients with acquired immunodeficiency syndrome (AIDS) and in neonates with presumed sepsis, and that rHuG-CSF may be a useful adjunct therapy in these patients. More recent studies have focused on enhancing neutrophil number and function in patients with infections not associated with neutropenia. These studies were approached cautiously because of the suggestion that neutrophils might non-selectively amplify the body's inflammatory response in the immunocompetent host and lead to inadvertent tissue injury. Preclinical models have provided a strong rationale for clinical studies to determine whether rHuG-CSF lessens the severity or duration of serious infections or their complications in patients with suboptimal outcome from antibiotics. These studies suggest that elevation of neutrophil levels in these settings is not only safe but has clinical benefit.

Animals

Managing diabetes through home care.

Diabetes management will hold an increasingly larger place in home care services as the population ages. Advocate Home Health Services in Oakbrook, Illinois, has developed a diabetes management program to help people with diabetes live more easily with this chronic disease.

Activities of Daily Living

Ecological Controls on the Evolutionary Recovery of Post-Paleozoic Crinoids

Analysis of morphological characters of a global sample of post-Paleozoic crinoid echinoderms shows that this group underwent a rapid diversification after the extinction at the end of the Permian to reach maximal morphological disparity by the Late Triassic, which is essentially the same evolutionary pattern seen during the group's early Paleozoic radiation. The accelerated morphological diversification of a single class implies that, even if clades surviving from the Paleozoic represented ecological incumbents that hindered the origin of new higher taxa, species within individual higher taxa rapidly exploited available ecological opportunities in the Mesozoic.

Journal Article

Biology and clinical potential of stem-cell factor.

Stem-cell factor (SCF) is a hematopoietic growth factor that acts on both primitive and mature progenitor cells. Preclinical studies have shown that recombinant SCF can protect against lethal irradiation, elicit multilineage hematopoietic responses and increases in bone marrow cellularity, and increase the number of circulating peripheral blood progenitor cells (PBPCs) in a dose-dependent manner. Both preclinical and early clinical studies using recombinant methionyl human SCF plus recombinant methionyl human granulocyte colony-stimulating factor (Filgrastim) have demonstrated increased PBPC mobilization as compared with the use of either factor alone. These data suggest a clinical role for the combination.

Animals

The new generation of recombinant human hematopoietic cytokines.

In the past year, the most exciting development in the field of hematopoietic growth factors has been the identification of the platelet-inducing factor Mpl ligand. Administration of recombinant Mpl ligand may alleviate the potential for hemorrhagic complications following cancer therapies. Stem cell factor continues to be studied clinically in the mobilization of peripheral blood cells for transplantation.

Biotechnology

The clinical utility of granulocyte colony-stimulating factor: early achievements and future promise.

Recombinant granulocyte colony-stimulating factor (rHuG-CSF) is a hematopoietic growth factor that acts selectively on the neutrophil lineage, and has had a major impact on clinical practice. Two forms are in clinical use: filgrastim has been approved for use in more than 45 countries for the amelioration of chemotherapy-induced neutropenia and restoration of granulopoiesis following bone-marrow transplantation and lenograstim has been approved in Europe and Japan. In some countries, rHuG-CSF is also approved for various other indications, such as severe chronic neutropenia. Infection and neutropenia are a major cause of morbidity and mortality following cytotoxic chemotherapy, and there is a known correlation between neutropenia and the risk of infection. Hematopoietic growth factors have been used successfully in the prevention and treatment of neutropenia. There is evidence to suggest that use of rHuG-CSF before the onset of neutropenia allows patients to receive the maximum benefit; however, patients who do not receive rHuG-CSF prophylactically still benefit from the use of rHuG-CSF for the treatment of febrile neutropenia. These patients have an accelerated neutrophil recovery and a shorter duration of febrile neutropenia. These effects seem to translate into a significant reduction in the number of patients requiring prolonged hospitalization. This paper reviews the use of rHuG-CSF in the treatment of febrile neutropenia and describes how it is routinely used by hematologists and oncologists in non-clinical trial settings.

Clinical Trials as Topic

Stem cell factor is a potent synergistic factor in hematopoiesis.

Stem cell factor (SCF), a ligand for c-kit, has a broad range of activities including effects on cells at or near the level of the multipotential stem cell as well as on committed cells. Preclinical studies show that SCF can protect against lethal irradiation, elicit multilineage responses in peripheral blood and bone marrow cellularity, and increase circulating peripheral blood progenitor cells (PBPC) in a dose-dependent manner. Recombinant human SCF has major clinical potential through its synergy with other factors, especially recombinant human granulocyte colony-stimulating factor, to enhance mobilization of PBPC.

Animals