Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

When F9 embryonal carcinoma (EC) cells are infected with retroviral vectors, the efficiency of expression of selectable genes is considerably lower than that in mouse fibroblasts infected with the same retroviral vectors. In this study, several retroviral vectors with regulatory sequences placed immediately 5' to a selectable gene were constructed, packaged, and used to infect mouse fibroblasts and F9 EC cells. With selection as an assay, there was a hierarchy of relative expression in F9 cells compared with that in mouse fibroblasts. These internally placed regulatory sequences are the source of the mRNAs detected in F9 EC cells, while both retroviral long-terminal-repeat promoters and internal promoters are the source of steady-state mRNAs in mouse fibroblasts. This effect was observable with both the internally placed herpes simplex virus thymidine kinase promoter and the Moloney murine leukemia virus promoter.
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PMID:Retroviral vector gene expression in F9 embryonal carcinoma cells. 304 Oct 45

Granulocytopenia is the single most important risk factor for infection in patients with acute leukaemia. There are limitations to the effective prophylaxis of infection in granulocytopenic patients, but practical measures include the management of the patient in a private hospital room, the requirement of all medical personnel and visitors to wash their hands carefully and to wear masks, restricting the patient to a low-bacteria diet devoid of fresh fruit, vegetables and salads, and the administration of oral antimicrobial agents for gastrointestinal decontamination. When fever develops, empirical therapy with a combination of an aminoglycoside plus an antipseudomonal beta-lactam should be started promptly. A double beta-lactam combination of cefoperazone or ceftazidime plus piperacillin can be substituted if nephrotoxicity is a concern. The addition of empirical intravenous amphotericin may be useful in patients who remain febrile and granulocytopenic on broad-spectrum antibiotics, especially if surveillance cultures indicate fungal colonization. Amphotericin is also the most reliable agent for the treatment of established fungal infections. Acyclovir is not recommended for prophylaxis in acute leukaemia patients but should be reserved for the treatment of well-documented and clinically significant herpes simplex viral infections. During periods of remission, most patients with AML remain free of infection except when they become granulocytopenic again during intensification or consolidation chemotherapy. On the other hand, children with ALL in remission may experience frequent infections unrelated to granulocytopenia as a consequence of their maintenance chemotherapy. Pneumocystis carinii, varicella zoster, and other viruses are common pathogens. Trimethoprim-sulphamethoxazole is effective prophylaxis against Pneumocystis carinii pneumonia in patients with ALL, while intravenous acyclovir is the drug of choice for treatment of varicella zoster infection. Transfusion therapy in the acute leukaemia patient is guided by the patient's peripheral blood counts and degree of sensitization to blood products. Generally, packed red blood cells are given in order to maintain the haematocrit at greater than 30%, while random-donor platelets are administered to keep the platelet count at greater than 20 X 10(9)/l. If refractoriness to platelet transfusions develops, HLA-matched platelets from family members or selected unrelated donors can be used. Similarly, washed or filtered red blood cells may be given to patients with previous and recurrent non-haemolytic febrile reactions to red blood cell transfusions.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Infection and transfusion therapy in acute leukaemia. 309 21

Thirty patients hospitalized for induction chemotherapy of acute leukemia were studied for incidence, severity, and clinical features of oral herpes simplex virus infections. In 50% of the patients with evidence of past herpes infection, recurrent oral herpes developed during the study. Herpes simplex virus was the major cause of oral mucosal lesions seen in patients with leukemia. A majority of the episodes involved multiple oral sites and caused large atypical lesions. All lesions healed after topical or intravenous acyclovir therapy. Herpes simplex infection should be ruled out in all cases of oral ulcers detected in patients being treated for leukemia.
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PMID:Oral herpes simplex infections in patients with leukemia. 347 Mar 73

Bromovinyldeoxyuridine (BVDU) is a highly potent and selective antiherpetic agent which offers great potential for the treatment of severe herpes simplex virus type 1 (HSV-1) and varicella-zoster virus (VZV) infections in cancer patients. BVDU inhibits the replication of HSV-1 and VZV at a concentration as low as 1-10 ng/ml; and the proliferation of tumor cells transformed with the HSV-1 thymidine kinase gene is even inhibited by BVDU concentrations lower than 1 ng/ml. Moreover, BVDU is inhibitory to Epstein-Barr virus replication in vitro at a concentration of 0.02 micrograms/ml. Due to the action of pyrimidine nucleoside phosphorylases, BVDU is rapidly degraded to the free pyrimidine base bromovinyluracil (BVU). In contrast to BVDU, which is cleared from the bloodstream within 2-3 hours, BVU persists in the plasma for at least 24 hours. During this period BVU can be converted again to BVDU upon administration of deoxythymidine, deoxyuridine or any other deoxyribonucleoside capable of transferring its deoxyribosyl moiety onto BVU. BVU owes its long persistence in the bloodstream to the fact that it does not act as substrate for dihydrothymine dehydrogenase, the enzyme that catalyzes the first step in the catabolic pathway of pyrimidines. On the contrary, BVU acts as an efficient inhibitor of this enzyme and thereby prevents the degradation of fluorouracil (FU), a well-known anticancer agent. As a consequence, BVDU via BVU enhances the antitumor activity of FU, as has been demonstrated in the murine P388 leukemia model. Thus, BVDU may be useful in anticancer chemotherapy from several viewpoints, e.g. for treatment of intercurrent herpesvirus infections, and, in combination with FU, for treatment of those malignant diseases that are amenable to FU therapy.
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PMID:Potential of bromovinyldeoxyuridine in anticancer chemotherapy. 375 35

We have used a producer NIH 3T3 cell line that secretes, together with the helper Moloney murine leukemia virus (Mo-MuLV), a transducing recombinant virus containing the neomycin-resistance gene linked to the Mo-MuLV long terminal repeat (LTR). By infecting three embryonal carcinoma cell lines, PCC4.aza1R, F9tk-, and Nulli-SCC1, with this recombinant virus, we have isolated many transductant clones that stably express the integrated neomycin-resistance gene. These clonal transductant lines consist of undifferentiated embryonal carcinoma cells as judged by morphology, tumorigenicity in 129/Sv mice, and cell-surface antigenic markers. Analysis of the integrated recombinant viral genes by Southern blot hybridization revealed that some of the lines have single copies, whereas others have multiple copies, probably in multiple sites. Although these transductant lines contained many copies of helper Mo-MuLV integrated in the cellular genome, expression of these helper viruses was not detected either by reverse transcriptase activity or by X-C plaque assay. Two F9tk--derived, G418-resistant transductant lines were superinfected with a second recombinant transducing virus that contains the herpes simplex virus thymidine kinase gene flanked by the Mo-MuLV LTR. The frequency of transduction to yield clones able to grow in hypoxanthine/aminopterin/thymidine medium was similar to that of the parental F9tk- cells. These results suggest that the expression of the neomycin-resistance gene, linked to MoMuLV LTR in the transductant embryonal carcinoma cell clones, is due to a cisacting mechanism(s).
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PMID:Isolation of embryonal carcinoma cell lines that express integrated recombinant genes flanked by the Moloney murine leukemia virus long terminal repeat. 385 93

The importance of viral infections in 150 children receiving therapy for leukemia was studied prospectively by application of comprehensive viral diagnostic procedures. One hundred five viral infections were identified, with herpes simplex virus and varicella-zoster virus being the most common agents. The spectrum of viruses associated with serious illness was wider than that in previous studies, and adenoviruses, parainfluenza viruses, rhinoviruses, and enteroviruses were important causes of morbidity. Viral isolation was the most sensitive diagnostic procedure used because complement fixation serology was falsely negative in two-thirds of cases. The occurrence of viral infection may be a previously overlooked important cause of respiratory tract infection and acute pyrexia of unknown origin. Viral infection rates were highest in patients with acute myeloblastic leukemia, in induction and relapse, and in patients treated with newer chemotherapeutic schedules. Thus, viruses are important pathogens in children with leukemia.
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PMID:Viral infections in childhood leukemia. 386 16

Among 78 patients who died after bone marrow transplantation, neurologic complications were present in 55 (70%) and were the cause of death in 5 (6%). Metabolic encephalopathy occurred in 29 patients (37%). CNS infections included aspergillosis (3), herpes simplex encephalitis (2), and Listeria monocytogenes meningitis (1). Six additional patients had neuropathologic changes possibly due to cytomegalovirus infection. Cerebrovascular complications occurred in five patients (two hemorrhages and three infarcts). All infarcts were associated with endocarditis. The rate of nonbacterial thrombotic endocarditis was significantly higher (p less than 0.001) than in the general autopsy population. CNS leukemia and therapy-induced injury were rare. There was no evidence of graft-versus-host disease involving the CNS.
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PMID:Neurologic complications of bone marrow transplantation. 388 33

The use of supralethal chemoradiotherapy followed by marrow transplantation has progressed from being an experimental approach applied only to a limited number of end-stage patients to an important therapeutic option appropriate for many adults with a variety of hematologic malignancies. With the use of transplantation, 10% to 30% of patients with relapsed leukemia and approximately 50% of patients with acute nonlymphoblastic leukemia in first remission can be cured. Cures have also been seen in a variety of other hematologic malignancies, including chronic granulocytic leukemia, preleukemia, hairy cell leukemia, and malignant lymphoma. Transplantation is currently limited by the need for a suitable marrow donor; by the complications of the transplant procedure, including infection, graft-versus-host disease, and the toxicities of intensive chemoradiotherapy; and by the risk of recurrent disease. Some of these limitations will likely be overcome as a result of current research. The use of partially matched family members and matched unrelated donors will make transplantation available to more patients. Some forms of posttransplant infection, including those associated with herpes simplex and cytomegalovirus, can now be prevented or treated. Improved methods of controlling graft-versus-host disease including T-cell depletion of marrow and the use of more effective immunosuppressive agents, as well as a better understanding of the toxicities of the preparative regimens, are making the transplant procedure safer and more tolerable. Finally, the development of better preparative regimens and transplantation earlier in the patient's disease course will likely allow for a larger percentage of patients to be cured.
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PMID:Treatment of acute leukemia in adults with chemoradiotherapy and bone marrow transplantation. 388 38

We describe here an infectious eucaryotic expression vector derived from Moloney Murine Leukemia (Mo-MuLV) provirus and recombined in plasmid pBR 322, for the expression of eucaryotic genes. Upstream of the cloning sites lie the 5' LTR and 700 bp of the gag sequences containing the splicing and encapsidation signals. Downstream of the cloning sites are situated the env gene and the 3' LTR containing the polyadenylation signal. So as to test the potential use of this vector, Herpes Simplex TK gene and E. Coli NeoR genes were cloned in the same transcriptional polarity as the viral LTRs. When DNA from the recombinant plasmid was transfected into mouse, rat, or human cell cultures, high yields of TK+ or NeoR colonies were obtained. Recombinant plasmids constructed with TK or NeoR genes in the opposite polarity failed to produce drug resistant colonies. Cotransfection with DNA of the Mo-MuLV competent helper provirus led to the rescue of chimeric virus capable of transmitting drug resistance.
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PMID:[Construction of an infectious retroviral vector for the expression of eucaryotic genes]. 392 76

Thermal destruction rate curves were determined for adenovirus 12, reovirus 1, and herpes simplex virus in sterile milk, raw milk, raw chocolate milk, and raw ice cream mix. At 40 to 60 C, the curves were asymptotic to the base line. At 65 C, which is near the pasteurization standard, the curves approached a first-order reaction. Thermal resistance studies, by means of in vivo assays, of Moloney and Rauscher leukemia viruses and Moloney and Rous sarcoma viruses indicated that Rous sarcoma was the most resistant. A comparison of the 12D processes of Rous sarcoma virus, reovirus 1, adenovirus 12, and herpes simplex virus in ice cream mix (the most protective of the suspending menstrua studied) with the U.S. Public Health Service pasteurization standard indicated an adequate safety factor in current pasteurization practices.
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PMID:Thermal resistance of certain oncogenic viruses suspended in milk and milk products. 433 Mar 13


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