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J D Broome

Publications and source records attributed to J D Broome.

At least 37 records · Page 2Linked to original sources
PubMed1992

Novel restriction fragment length polymorphisms in the cellular oncogene SEA.

The human homologue of the SEA oncogene has been mapped recently to chromosome band 11q13. While studying the possible involvement of this gene in the variant translocation t(9;22;11) (q34;q11;q13) in a case of chronic myelogenous leukemia, we identified novel polymorphisms for XbaI and SacI restriction enzyme sites in the SEA gene. Frequency of the polymorphic alleles was studied in 100 samples from healthy controls, 94 samples from patients with non-Hodgkin's lymphoma, 25 samples from patients with benign lymphadenopathy, and 38 samples from patients with chronic myelogenous leukemia. XbaI digestion showed a three-allele polymorphism with two frequent alleles A (8.0 kb) and B (9.2 kb) and a rare allele (5.8 kb). After SacI digestion the probe identified two primary genotypes. Genotype I showed two hybridizable DNA fragments, one each of 6.6 and 3.5 kb. In genotype II the 3.5 kb fragment was absent, instead two smaller fragments, one each of 1.9 kb and 1.6 kb were present. The 6.6 kb fragment (allele AA) had three polymorphic sites generating 6.2 kb fragment (allele BB), 7.4 kb fragment (allele CC), and 7.8 kb fragment (allele DD). Frequencies of the two genotypes and the four alleles followed Mendelian proportions in all the samples studied. Furthermore, this study shows the importance of restriction map analysis of DNA in the vicinity of the probe of an oncogene to distinguish natural polymorphisms from the disease-related rearrangements in the gene.

DNA↗
PubMed1987

Mercaptoethanol protects glutathione depleted cells.

Buthionine sulfoximine depleted the glutathione (GSH) level of mouse lymphoma L1210A cells in culture to 6% of control and killed the cells within 48 hours in medium supplemented with fetal calf serum or bovine serum albumin. Mercaptoethanol or alpha-thioglycerol but not GSH or cysteine added to the medium protected the cells from the effect of GSH depletion. Horse serum was also protective, and this effect was removed by dialysis over 65 hours and could not be restored by adding GSH. Mercaptoethanol alone had a protective action in the dialyzed sera. The results suggest that mercaptoethanol may act independently and perform the functions of GSH.

Animals↗
PubMed1984

L1210(A) mouse lymphoma cells depleted of glutathione with L-buthionine-S-R-sulfoximine proliferate in tissue culture.

L1210(A) mouse lymphoma cells have been adapted to long-term tissue culture in the presence of L-buthionine-S-R-sulfoximine in concentrations of 1-10 mM. As a result of the inhibitory action of this compound on the synthesis of gamma-glutamylcysteine, the dipeptide precursor of glutathione, the cells are depleted of more than 90% of their normal cellular glutathione content. The residual 10% seems to resist depletion at high concentrations of buthionine sulfoximine. Glutathione depleted cells proliferate at a rate similar to that of non-depleted cells, and show full viability. Upon transfer of cells into inhibitor-free medium, they fully regain their original glutathione content. It is concluded that these cells contain at least two pools of glutathione: a large cytoplasmic pool and a smaller, possibly mitochondrial, pool. It is further concluded that the large pool of cytoplasmic glutathione is not obligatory for cell growth and mitosis.

Animals↗
PubMed1978

Production of autoinhibitory factors by mouse lymphoma cells in vitro and its relationship to thiol dependence.

Five different kinds of mouse lymphoma cells conditioned culture medium so that it became inhibitory to thiol-dependent cells but not to thiol-independent cells. Conditioning was rapid and appeared to be complete in 1-3 hr. The inhibitory effects could be reversed by concentrations of 2-mercaptoethanol higher than those usually required for growth promotion. Inhibitory factors were concentrated by ultrafiltration and chromatography on Sephadex G-10 which showed their apparent molecular weights to be 300-600. The factors were stable at 100 degrees and to proteases but were inactivated (after reduction) by iodoacetamide, indicating that they may be thiols or disulfides.

Animals↗
PubMed1977

Recovery of Paramyxovirus from the jejunum of patients with multiple sclerosis.

Paramyxovirus, presumably measles, has been recovered by cocultivation or cell-fusion techniques from jejunal biopsy specimens of 6 consecutive patients with multiple sclerosis. Virus has been identified by immunofluorescence of antigen in infected HEp-2 and BSC-1 cells, by electron microscopy, and by haemagglutination of rhesus-monkey erythrocytes.

Animals↗
PubMed1977

Jejunal immunopathology in amyotrophic lateral sclerosis and multiple sclerosis. Identification of viral antigens by immunofluorescence.

Jejunal mucosa from 7 patients with amyotrophic lateral sclerosis (A.L.S.), 20 newly reported patients with multiple sclerosis (M.S.), and 35 control patients without either disease was studied by immunofluorescence. An immune reaction was present in all A.L.S. specimens and consisted of altered ratios of immunoglobulin-labelled cells in the lamina propria, complement-labelled cells in the same location, and, in some, immunoglobulin and complement deposits in the epithelial basement membrane. Poliovirus antigen was detected in 4 cases, and in 1 of the these cases measles antigen was also present. A fifth specimen showed large amounts of herpesvirus antigen. In 2 cases studied at necropsy, both viral infection and immunological change was confined to the proximal jejunum. Measles antigen was identified in every case of M.S., and in biopsy specimens from 16 of the 20 M.S. patients immunological reactions similar to those seen in A.L.S. were present. With 2 exceptions, the controls did not show these changes in the jejunal mucosa. The exceptions were a patient with Friedreich's ataxia, who had an increase of IgG-labelled cells and some complement-bearing cells in the lamina propria, and a patient diagnosed as having non-tropical sprue, in whom large quantities of herpes antigen were seen.

Amyotrophic Lateral Sclerosis↗
PubMed1977

Light and electron microscopic studies of "nude" mice CNS after subcutaneous administration of the E variant of the encephalomyocarditis (EMC) virus.

Sixteen 3 month old "nude" mice, 24 of their litter mates and 30 Swiss mice were injected subcutaneously with 0.1 ml suspension of the E variant of the encephalomyocarditis (EMC) virus. While the mortality rate of the litter mates and Swiss mice during 5-7 days after inoculation was more than 40%, none of the "nude" mice died during the experiment. The surviving animals were sacrificed at 24 h intervals from day one to seven days after injection. Brain suspensions assayed for the presence of the virus yielded significant titers at 24 h in all groups, which increased during 7 days. The litter mates and Swiss mice showed proliferation of lymphocytes and microglial cells in the perivascular areas of the brain during the fifth to the seventh day. The "nude" mice, on the other hand, displayed no perivascular lymphocytic infilteration during the same periods. Ultrastructurally, all groups showed aggregates of ribosomes in the cytoplasmic matrix on the third day, which became enlarged in size on the 5th day. At 7 days, both litter mates and Swiss mice showed an increased number of necrotic cells, while these changes were not observed in the "nude" mice. These findings suggest that the high mortality rate in immunologically normal mice was related to the efforts of T cells to eliminate virus-infected cells and to produce extensive necrosis, while T cell-depleted animals showed good survival rates.

Animals↗
PubMed1977

Macromolecular inhibitory factor for lymphoid cells produced by mouse macrophages.

Supernatants of high density cultures of mouse peritoneal macrophages were inhibitory to homologous lymphoid cells in vitro by a number of parameters: proliferation and survival of lymphoma cells was impaired, the immune response of spleen cells to sheep red cells and to Concanavalin A (Con A) was decreased. Inhibition was due to factor(s) with mol. wt of approximately 110,000 as estimated by gel filtration. Activity was stable to heating at 56 degrees, and was resistant to trypsin but not to pronase.

Animals↗
PubMed1975

Studies of the mechanism of growth promotion of lymphoma cells by 2-mercaptoethanol in vitro.

Rates of incorporation of thymidine and uridine, but not leucine, decrease markedly in L1210 (V) cells within 1 hour of incubation in DULBECCO'S medium containing 10% serum. 2-Mercaptoethanol (2-ME) after a latent period of more than 5 hours causes an increase in nucleotide incorporation. Bovine serum albumin can substitute for serum in the medium, but a higher concentration of 2-ME is required for growth. After charcoal treatment of the albumin less 2-ME is required. These experiments suggest that inhibition of the tumor cells is caused by a serum factor whose effect is antagonized by the thiol.

Animals↗
PubMed1973

Promotion of replication in lymphoid cells by specific thiols and disulfides in vitro. Effects on mouse lymphoma cells in comparison with splenic lymphocytes.

Numerous lines of mouse lymphoid tumors (13 of 22 tested) showed, with increased sensitivity, a property of normal mouse splenic lymphocytes, the potential for growth promotion in vitro by specific thiols added to standard culture media. For lymphoma L1210 (V), structure activity relationships were examined; 9 of 30 thiols promoted growth; the most active was alpha-thioglycerol, effective at 0.2 microM. Thiols became oxidized under conditions of tissue culture and had half-lives of less than 8 h. Disulfides of active thiols promoted growth of lymphoma cells. The mitogenic response of splenic lymphocytes to lectins was increased by thiols-disulfides which promoted the growth of lymphoma cells, but the response varied with the mitogen preparation used and under some conditions thiols-disulfides were inhibitory.

Animals↗