Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0002871 (anemia)
 52,094 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cats infected with molecularly cloned FeLV-FAIDS develop an immunodeficiency syndrome characterized by persistent antigenemia, decline in circulating CD4+ T lymphocytes, and impaired T-cell-dependent immune responses and opportunistic infection. We evaluated the capacity of PMEA to inhibit the replication of FeLV-FAIDS in vitro and to inhibit the progression of FeLV-FAIDS infection in vivo. We found that PMEA inhibited replication of FeLV-FAIDS by greater than or equal to 50% at concentrations of greater than or equal to 0.5 microgram/ml (1.63 microM) in feline fibroblasts and prevented T lymphocyte killing at concentrations of 3 micrograms/ml. PMEA administered to cats at dosages of greater than or equal to 6.25 mg/kg/day from 0 to 49 days after FeLV-FAIDS infection prevented the development of persistent antigenemia and the induction of immunodeficiency disease. In contrast to placebo treated controls, cats successfully treated with PMEA contained viral infection, developed neutralizing antibody, and resisted a second virulent virus challenge without further therapy. Manifestations of PMEA toxicity produced by higher dosages (25 or 12.5 mg/kg/day) were anemia, leukopenia, and diarrhea. These results indicate PMEA to be a potent antiretroviral agent effective in aborting fatal progression of FeLV-FAIDS infection when therapy is initiated at the time of virus exposure.
 ...
PMID:Early therapy of feline leukemia virus infection (FeLV-FAIDS) with 9-(2-phosphonylmethoxyethyl)adenine (PMEA). 166 30

The uses and limitations of the western blot (WB) and radioimmunoprecipitation assay (RIPA) techniques for study of feline immunodeficiency virus (FIV) and FeLV were evaluated. Western blot analysis was used to detect antigenic relatedness between the 2 lentiviruses. Using a rabbit serum directed against p26 of the equine infectious anemia virus (EIAV) and anti-EIAV horse serum obtained from an infected horse, cross-reactivity with p24 of FIV was revealed. Cat sera obtained late after experimentally induced FIV infection recognized p26 of EIAV, which indicates reciprocal cross-reactivity. For RIPA, FIV was metabolically labeled, and virus-coded proteins were identified, using immunoprecipitation. Polypeptides with apparent molecular mass of about 15, 24, 43, 50, 120, and 160 kilodaltons were detected. An additional polypeptide of 10 kilodaltons was found only by use of WB analysis.
 ...
PMID:Use of western blot and radioimmunoprecipitation for diagnosis of feline leukemia and feline immunodeficiency virus infections. 166 78

Early studies with the Gross passage A leukemia virus demonstrated that retroviral infection suppresses cellular and humoral immune responses. In extensive studies of the feline leukemia (FeLV) virus, which can induce profound immunodeficiency disease, are generative anemia and lymphoid, myeloid and erythroid neoplasia, the immunosuppressive effects of this retrovirus could be attributed to the actions of the retroviral envelope protein p15E. We found that a highly conserved, synthetic 17 amino acid peptide synthesized by Cianciolo and co-workers that is homologous to the hydrophilic portion of the otherwise hydrophobic transmembrane envelope protein can suppress polyclonal activation of B-cells, impair production of gamma- and alpha-interferon, inhibit production of interleukin-2, inhibit expression of IL-2 receptors, and suppress responses of cytotoxic lymphocytes. In analyses with inactivated preparations of the human immunodeficiency virus, with Pahwa et al. we demonstrated that purified non-infectious retrovirus and also retroviral proteins, in particular gp120, appeared to produce some of the immunosuppressive properties of HIV, particularly suppression of B-cell activation in response to known B-cell stimulants irrespective of T-cell influence, suppression of T-helper cell functions essential to B-lymphocyte responsiveness, and impaired function of immunoglobulin-secreting cells. Other investigators have also reported strong immunosuppressive or immunostimulatory influences for components of the HIV retrovirus and also gp120 through yet poorly elucidated but certainly complex actions on both T- and B-lymphocyte-mediated immune functions.
 ...
PMID:In vitro immunomodulation and in vivo immunotherapy of retrovirus-induced immunosuppression. 166 53

To determine the safety, maximum tolerated dose, and preliminary efficacy of concomitant interferon-alpha and zidovudine therapy in AIDS-related Kaposi's sarcoma (KS), 56 patients with biopsy-proven KS and documented human immunodeficiency virus type 1 (HIV) infection were enrolled into a phase I study. Interferon-alpha was given intramuscularly at a dose of 9, 18, or 27 mu once a day and zidovudine was administered as 100 or 200 mg every 4 h for 8 weeks followed by a 48-week maintenance period. The major toxicities were anemia, neutropenia, and hepatotoxicity. Neutropenia was dose limiting with 1,200 mg of zidovudine/day and the lowest dose of interferon-alpha (9 mu/day). Hepatotoxicity was dose limiting with 27 mu of interferon and 600 mg of zidovudine/day. Cumulative dose-related anemia or neutropenia was not seen during long-term follow-up. The maximum tolerated doses for the combination were defined as 18 mu daily for interferon-alpha and 600 mg daily for zidovudine. Variable changes in CD4 lymphocytes occurred during the first 8 weeks of therapy. At higher doses of the combination, sustained increases in median CD4 lymphocyte numbers were noted (p less than 0.001). In HIV antigenemic patients, progressive antigen suppression was seen with increasing doses of the combination (p less than 0.005). The overall antitumor response rate was 47%. Tumor regression was associated with better survival benefits (p less than 0.001) and a pretreatment CD4 cell count greater than or equal to 200 cells/mm3 (p = 0.01). In conclusion, intermediate doses of interferon-alpha and lower doses of zidovudine appear to be relatively well tolerated and associated with disease improvement, including survival benefits.
 ...
PMID:A phase I study of recombinant human interferon-alpha 2a or human lymphoblastoid interferon-alpha n1 and concomitant zidovudine in patients with AIDS-related Kaposi's sarcoma. 167 May 85

The pathophysiology of anemia in patients with human immunodeficiency virus (HIV) infection is multifactorial. In order to determine the role of erythropoietin (EPO) response as a cause of the anemia, serum levels were determined by direct radioimmunoassay in 110 symptomatic patients with various stages of HIV infection. Symptomatic patients (ARC and AIDS) not receiving zidovudine (ZDV) therapy demonstrated a strong inverse relationship between serum EPO and hemoglobin levels (p = 0.01 and p less than 0.001, respectively). Patients with AIDS who were anemic while receiving ZDV demonstrated serum EPO levels that ranged from normal to markedly elevated (9-3,390 mU/ml). The diversity of serum EPO levels in patients with HIV infection and anemia suggests that the etiology of anemia in these patients and their potential response to recombinant human EPO may not be uniform.
 ...
PMID:Serum erythropoietin titers in patients with human immunodeficiency virus (HIV) infection and anemia. 154 78

An epidemiologic study was initiated in 1987 to evaluate the long-term safety and efficacy of zidovudine in patients with advanced human immunodeficiency virus disease. Data from 886 patients with the acquired immunodeficiency syndrome (AIDS) or AIDS-related complex and CD4+ lymphocyte count less than 0.25 x 10(9)/L are reported. Eighteen-month survival was 67% for the cohort. Pretreatment factors associated with increased survival time included index diagnosis of AIDS-related complex, hematocrit of 0.35 or greater, CD4+ lymphocyte count of 0.15 x 10(9)/L or greater, high functional status, and time from diagnosis of AIDS to treatment of less than 60 days. By proportional hazards analysis, development of serious anemia was the most significant factor associated with early death. Receiving zidovudine for a high proportion of time significantly improved chances of survival even if anemia developed. Serious leukopenia occurring in 37% and serious anemia occurring in 32% of patients. Nonhematologic adverse events were uncommon and no previously unreported adverse events were seen.
 ...
PMID:Long-term safety and efficacy of zidovudine in patients with advanced human immunodeficiency virus disease. Zidovudine Epidemiology Study Group. 167 37

Twenty-four patients infected with human immunodeficiency virus type 1 (HIV-1) who had CD4+ counts of 0.2-0.5 x 10(9) cells/l received granulocyte-macrophage colony-stimulating factor (GM-CSF) in combination with zidovudine plus escalating doses of daily subcutaneous interferon-alpha. Mean neutropenia-inducing doses of interferon-alpha were 9.4 x 10(6) and 10.6 x 10(6) IU/day for groups receiving 100 or 200 mg zidovudine every 4 h, respectively. Mean GM-CSF doses used to reverse neutropenia were 0.64 and 0.63 microgram/kg/day for these two groups, respectively, although the mean minimum effective GM-CSF dose for both was only 0.30 microgram/kg/day. Serum p24 antigen declined greater than 70% in all 5 antigenemic patients. Toxicities included a dose-dependent increase in lymphokine-like side effects (100%), anorexia and weight loss (42%), fatigue (42%), and anemia (50%). While toxicities of the combination can be significant, low-dose GM-CSF readily ameliorated neutropenia associated with zidovudine and interferon-alpha therapy without adversely affecting the antiviral properties of the combination.
 ...
PMID:A phase I/II trial of zidovudine, interferon-alpha, and granulocyte-macrophage colony-stimulating factor in the treatment of human immunodeficiency virus type 1 infection. 167 45

Feline immunodeficiency virus (FIV) grown in cat lymphocyte and thymocyte cultures was labelled with L-[35S]methionine or [3H]glucosamine and virus-coded proteins were identified using immunoprecipitation. Polypeptides with apparent Mr values of 15K, 24K, 43K, 50K, 120K and 160K were detected. An additional polypeptide of 10K was detected by Western blot analysis. The two highest Mr species sometimes appeared as one band, of which only the 120K polypeptide was glycosylated. In the presence of tunicamycin gp120 was no longer detectable and a non-glycosylated precursor of 75K was found instead. Pulse-chase experiments suggested that the smaller polypeptides p24 and p15 are cleavage products of both p160 and p50. Western blot analysis using a rabbit serum directed against p26 of equine infectious anaemia virus (EIAV) and an anti-EIAV horse serum from a field case of infection revealed a cross-reactivity with p24 of FIV. Cat sera collected late after experimental FIV infection recognized p26 of EIAV, indicating a reciprocal cross-reactivity.
 ...
PMID:Intracellular proteins of feline immunodeficiency virus and their antigenic relationship with equine infectious anaemia virus proteins. 169 Feb 64

Zidovudine is now used extensively in an effort to control infection with the human immunodeficiency virus (HIV). The drug is associated with major hematologic toxicity, especially anemia and granulocytopenia. Conservative management of hematologic toxicity includes dosage reduction or cessation of therapy, diagnosis and treatment of chronic debilitating diseases, and supportive care, such as blood transfusions. New investigational agents, including hematopoietic growth factors, are being studied to combat the toxicities associated with zidovudine. The efficacy of these agents has yet to be established. Recent advances in drug efficacy at reduced dosage and in combination therapy promise to permit use of zidovudine with markedly reduced toxicity.
 ...
PMID:Hematologic toxicity of zidovudine in HIV-infected patients. 169 80

Hypericin and pseudohypericin are naturally occurring polycyclic quinones which have recently been shown to inhibit the infectivity of several retroviruses, including human immunodeficiency virus. To better understand the antiviral mechanisms of these compounds, hypericin and a series of analogous quinones were synthesized and tested for anti-retroviral activity against equine infectious anemia virus (EIAV). Treatment of EIAV-infected cells with hypericin reduced the production of infectious virus by 99.99%. None of the analogs were found to inhibit virus replication. These results suggest that the complete ring structure of hypericin is required, but not sufficient, for antiviral activity.
 ...
PMID:Antiretroviral activity of synthetic hypericin and related analogs. 169 34


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