Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of 10 days of total energy deprivation on lymphocyte functions and cell-mediated immunity was evaluated in fourteen healthy, normal-weighted males. Lymphocytes from seven of the subjects were tested in vitro. A significant depression was noted of the DNA synthesis after stimulation with pokeweed mitogen and PPD while there was no effect on the response to concanavalin A. No change was noted in the percentages and total numbers of circulating B and T lymphocytes and monocytes. The delayed skin reactivity following intracutaneous PPD and mumps antigen was not different from non-starving control subjects.
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PMID:Acute energy deprivation in man: effect on cell-mediated immunological reactions. 108 37

Studies of blood lymphocytes from 4 patients with pure red cell aplasia were performed with lymphocyte surface markers, and with various in vitro tests for lymphocyte functions. Pathologically low B-lymphocyte values were found. In contrast, no marked deviation from normals were seen for T-lymphocytes and Fc-receptor-bearing lymphocytes thought largely to represent non-B, non-T-lymphocytes. In 3 patients normal lymphocyte transformation was found with unspecific and specific mitogens, while the DNA-synthesis induced by unspecific mitogens was subnormal in the fourth patients. The lymphocyte-mediated PHA-induced cytotoxicity against target cells in vitro was subnormal in 2 patients, while no depression was seen in antibody-dependent cytotoxicity mediated in vitro by lymphocytes (K-cells). It is concluded that considerable immunological abnormalities are associated with pure red cell aplasia, and the possible significance of this is discussed.
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PMID:Abnormal lymphocyte populations in pure red cell aplasia. 108 44

Suspensions of human bone marrow cells were incubated with various concentrations of phenobarbitone or phenytoin sodium for 2 h, and the effects of this incubation on the subsequent incorporation of 3H-thymidine and3H-leucine into DNA and protein, respectively, were studied. Both drugs caused a depression of 3H-thymidine incorporation and this phenomenon was not prevented by the addition of 100 mug of pteroyl-glutamic acid, folinic acid or 5-methyltetrahydrofolate per ml of marrow culture. The lowest concentration of drug which caused a statistically significant depression of 3H-thymidine incorporation was 200 mug per ml for phenobarbitone and 50 mug per ml for phenytoin sodium. Both phenobarbitone and phenytoin sodium also caused an increase in the incorporation of 3H-leucine at concentrations of 50 and 20 mug per ml, respectively, suggesting the possibility that a stimulation of protein synthesis within erythropoietic cells may play an important role in the development of anticonvulsant-induced macrocytosis.
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PMID:Effects of anticonvulsant drugs on the synthesis of DNA and protein by human bone marrow cells in vitro. 108 45

There is a difference in the extent of inhibition of thymine dimers (TT) excision in ultravioley (UV) irradiated cells of E. coli after preirradiation depression of protein and DNA syntheses induced by a simultaneous deprivation of essential amino acids (AA-) and thymine(T-) or by deprivation of essential amino acids and addition of nalidixie acid (NAL+). This difference has been noted in both E. coli B/r Her+ and E. coli K12 SR20 uvr+ cells. Depression of DNA synthesis with the aid of malidixic acid as exogenous agent will inhibit TT excision to a lesser degree than depression of DNA synthesis by thymine starvation. The extent of TT excision has no appreciable influence on restoration of the sedimentation profile of newly synthesized DNA nor again on UV resistance of cells in conditions of dark repair. At the time when there are TT still present in DNA, the DNA molecule, having the size of the molecule of unirradiated cells, will become synthesized.
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PMID:Comparison of the effect of nalidixic acid and thymine deprivation on excision repair in Escherichia coli. 109 65

Clinical observations have long suggested immunologic compromise in burned patients. Resolution of the immune system into cooperative dual components of T-cells mediating delayed hypersensitivity and B-cells mediating antibody responses prompted the present survey of T-cell and B-cell changes after acute thermal burn injury. Adults and children sustaining extensive burn injuries were studied for up to 60 days after injury. T-cell function was assessed by lymphocyte counts, in vitro lymphocyte synthesis of RNA and DNA with and without mitogenic stimulation, and lymphocyte response and stimulatory capacities in the mixed lymphocyte culture (MLC) reaction. B-cell function was studied by quantitation of the major classes of circulating immunoglobulins. Transient lymphocytopenia, increased RNA and DNA synthesis rates by both mitogenstimulated and unstimulated lymphocytes, and impairment of lymphocyte response and stimulation in the MLC were observed early in the postburn period. These parameters tended to normalize by the third week after injury. Immunoglobulin levels, particularly IgG, were depressed significantly the first week postburn, but were normal or elevated by 60 days. These studies document both T-cell and B-cell changes postburn,which appear to be reversible with the recovery phase. A transient shift of circulating lymphocytes toward the B-cell type is suggested and early depression of immunoglobulin levels is notable. Both types of changes likely contribute to the immunologic compromise of the acutely burned patient.
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PMID:Lymphoid response of the burn patient. 109 52

Embichin inhibited the matrix activity of chromatin and DNA in the RNA-polymerase system in vitro much more than its monofunctional analogue. Chromatin possessed a greater sensitivity to the action of embichin in comparison with the deproteinised DNA. However, with the action of a monofunctional embichin analogue there was a greater reduction of the matrix activity of DNA in comparison with chromatin. The depression mechanism of the matrix activity of chromatin with the action of embichin was apparently associated with the capacity of the latter to form the DNA-protein bonds in the chromatin composition.
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PMID:[Effect of embichin (HN2) and its monofunctional analog (HN1) on chromatin and DNA matrix activity in an in vitro RNA-polymerase system]. 110 80

Mutation of the gene m3 of phage P22 causes permanent depression of macromolecular synthesis in the infected host and thus inhibits phage development as indicated by burst size and lysozyme production. The permanent depression of macromolecular synthesis is most probably due to blockage of the transport process. The m3 allele is dominant over m+. m3 allows some transcription of phage genes (however, the difference between early and late function is not clear). The inhibitory effect of m3 on DNA synthesis may be indirect.
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PMID:Effect of m3 gene on the development of phage P22. 110 21

It had been found earlier that the excision repair mechanism in E. coli B/R Hcr+ could be depressed by preirradiation, amino acid and thymine starvation; such an interference proved to have no appreciable influence on survival after ultraviolet irradiation. A comparison between Hcr+ and Hcr- cells had revealed that the former were capable of tolerating a greater amount of unexcised dimers than the latter. In this paper it is demonstrated that the above-mentioned pretreatment will depress excision activity also in cultures of E. coli K12 and E. coli 15T- both strains of the uvr+ rec+ genotype. A comparison of two E. coli K12 strains of the uvr+ and uvr- genotype shows that uvr+ cells also have a greater capacity to tolerate unexcised dimers. To throw light on the nature of that increased capacity to tolerate unexicsed dimers we have compared restoration of DNA daughter chains in cells of the uvr+ and uvr- genotype and found that integrity of uvr loci is a conditio sine qua non for an effective restoration of daughter chains, but that depression of excision activity by the mentioned pretreatment does not influence restoration of DNA daughter chains. This suggest that uvr loci are involved not only in excision but also in postreplication mechanism of DNA repair.
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PMID:Function of the UVR marker in dark repair of DNA molecules. 110 8

Most genetic characteristics of T4 recombination (the effects of chromosomal termini on recombination, heterozygosity, high negative interference, base mismatch repair, polarized segregation, and the stimulation or depression of recombination in response to phage mutations or external perturbations) can be expressed adequately in terms of our present understanding of the molecular events of T4 infection cycles. T4 DNA replication begins and ends with linear chromosomes and does not require a circular intermediate. Replication is bi-directional, possibly from multiple origins. Two phases of replication are distinguishable: (a) an early mode during which about 20 progeny copies of infecting chromosomes are made prior to (b) a recombination-dependent mode during which progeny molecules associate to form covalently joined linear concatemers. Further replication is generally arrested if concatemerization is prevented. T4 DNA recombination depends on the production of single-stranded gaps and termini. If replication is inhibited, the single-stranded regions are produced by deoxyribonuclease activities. In contrast, during partial replication of damaged chromosomes, during slow replication when enzymes or subtrates are limited, and during normal replication, they are formed by strand-displacement DNA polymerization. As a rule, any agents or perturbations that cause an accumulation of single-stranded regions stimulate recombination, whereas efficient repair of such regions depresses it. Both the preservation and pairing of single-stranded regions are facilitated by the gene-32 single-stranded DNA binding protein. Covalent repair of strand interruptions between recombined DNA segments requires polymerases or nucleases as well as ligases.
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PMID:Molecular and genetic recombination of bacteriophage T4. 110 66

Antigen-induced depression of spleen DNA synthesis was studied in NZB and CBA/J mice. This phenomenon, a measure of T suppressor cell activity, normally decreases as a consequence of aging. However, NZB mice have an accelerated loss of antigen-induced depression that can be restored by treatment with thymosin or injection of 1-month-old NZB thymocytes. The restoration by thymosin declined between 1 and 2 weeks after treatment, but could be induced again after a second exposure to thymosin. These results suggest a potential for reversible but repeatable restoration of suppressor cell activity in NZB mice.
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PMID:Reversible restoration by thymosin of antigen-induced depression of spleen DNA synthesis in NZB mice. 112 26


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