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1.
Int J Obstet Anesth ; 41: 65-70, 2020 02.
Article in English | MEDLINE | ID: mdl-31353179

ABSTRACT

BACKGROUND: The objective of this study was to evaluate the course of pregnancy and delivery of obstetric patients admitted for intensive care, and determine the health status of their infants. METHODS: This was a retrospective register-based study. Four university hospitals in Finland participated. Obstetric patients admitted to the intensive care unit in any trimester of pregnancy, during delivery or up to 42 days post partum were identified from clinical information systems over a five-year study period. Parturient and infant data were collected from the Medical Birth Register. RESULTS: During the study period (2007-2011), 283 obstetric patients were identified from the clinical information system. The most common reason for admission was hypertensive complications (58%), followed by obstetric haemorrhage (25.1%). Advanced maternal age, nulliparity and multiple pregnancies were associated with obstetric intensive care unit admissions. Of patients admitted to intensive care, 68.9% delivered by unscheduled caesarean section. Nearly 60% of neonates were born preterm, 56.1% needed treatment in a neonatal intensive care unit or an observation unit and 4.6% died within one week. CONCLUSION: Advanced maternal age, nulliparity and multiple pregnancy were more common among intensive care unit-admitted women than in the general obstetric population. The main causes for admission were hypertensive complications and obstetric haemorrhage. Compared with the general obstetric population, neonates of intensive care unit-admitted mothers were eight times more likely to require treatment on a neonatal ward and their risk of neonatal death was also eight times greater.


Subject(s)
Delivery, Obstetric , Intensive Care Units , Adult , Female , Health Status , Humans , Hypertension/complications , Infant, Newborn , Male , Maternal Age , Postpartum Hemorrhage/epidemiology , Pregnancy , Retrospective Studies
2.
Eur J Cancer Care (Engl) ; 10(1): 6-11, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11827269

ABSTRACT

A chronic illness, such as cancer, causes permanent changes in a person's way of life and their way of adapting to changes. The purpose of this study was to describe the coping strategies and resources of adolescents and young adults with cancer. The data were collected by interviewing adolescents and young adults aged 16-22 (n = 14) who had had cancer for more than 2 months and who came to a university hospital for treatment or control check ups. The interview material was analysed by content analysis. Emotion-focused, appraisal-focused and problem-focused coping strategies were used. The major coping strategies were social support, belief in recovery and getting back to normal life as soon as possible. The subjects discussed with health care providers their disease, its treatment and how they could cope with everyday life as well as their energy and will-power to cope. The family was the most important source of emotional support. Also, gaining knowledge about cancer and its treatment was a good coping strategy. Moreover, a positive life attitude, belief in one's own resources, belief in God, earlier life experiences and willingness to fight against the disease were resources for coping with cancer.


Subject(s)
Adaptation, Psychological , Neoplasms/psychology , Adolescent , Adult , Humans , Interviews as Topic , Neoplasms/classification
3.
J Gen Virol ; 78 ( Pt 6): 1241-6, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9191914

ABSTRACT

Two mutant potato virus X (PVX) movement protein (MP) genes (m 12K-Sal and m 12K-Kpn) were obtained by inserting specific linkers at the boundary between the N-terminal hydrophobic and putative transmembrane segment, and the central invariant hydrophilic region of the respective 12 kDa, 12K, triple gene block (TGB) protein. Several transgenic potato lines which expressed m 12K-Sal or m 12K-Kpn to different degrees were resistant to infection by PVX, potato aucuba mosaic potexvirus and the carlaviruses potato virus M and S over a wide range of inoculum concentrations (3-300 micrograms/ml). However, they were not resistant to potato virus Y, which lacks a TGB protein. We suggest that the resistance of m 12K-Sal and m 12K-Kpn transgenic potato lines is MP-derived and not RNA-mediated.


Subject(s)
Plant Viruses/genetics , Viral Proteins/physiology , Amino Acid Sequence , Molecular Sequence Data , Plant Viral Movement Proteins , Plants, Genetically Modified , RNA, Viral/physiology
4.
Mol Gen Genet ; 248(6): 649-56, 1995 Oct 25.
Article in English | MEDLINE | ID: mdl-7476867

ABSTRACT

Petunia mutant RL01 was transformed with maize A1 and gerbera gdfr cDNAs, which both encode dihydroflavonol-4-reductase (DFR) activity. The same Agrobacterium vector and the same version of the CaMV 35S promoter were used in both experiments. Transformation with the cDNAs resulted in production of pelargonidin pigments in the transformants. However, the A1 and gdfr transformants showed clearly different phenotypes. The flowers of the primary A1 transformants were pale and showed variability in pigmentation during their growth, while the flowers of the gdfr transformants showed intense and highly stable coloration. The color difference in the primary transformants was reflected in the expression levels of the transgenes as well as in the levels of anthocyanin pigment. As previously reported by others, the instability in pigmentation in the A1 transformants was more often detected in clones with multiple copies of the transgene and was associated with methylation of the 35S promoter and of the transgene cDNA itself. In the gdfr transformants, the most intense pigmentation was observed in plants with multiple transgenes in their genome. Only rarely was partial methylation of the 35S promoter detected, while the gdfr cDNA always remained in an unmethylated state. We conclude that the properties of the transgene itself strongly influence the inactivation process. The dicotyledonous gdfr cDNA with a lower GC content and fewer possible methylation sites is more 'compatible' the genomic organization of petunia and this prevents it being recognized as a foreign gene and hence silenced by methylation.


Subject(s)
Gene Expression Regulation, Plant , Pigmentation/genetics , Plants, Genetically Modified/genetics , Transformation, Genetic/genetics , Transgenes , Alcohol Oxidoreductases/genetics , Anthocyanins/analysis , Anthocyanins/chemistry , Blotting, Northern , Blotting, Southern , DNA, Complementary/genetics , Flavonoids/biosynthesis , Flavonoids/genetics , Gene Dosage , Genetic Vectors , Methylation , Mutation/genetics , Phenotype , Pigments, Biological/biosynthesis , Pigments, Biological/genetics , Promoter Regions, Genetic/genetics , Zea mays/genetics
5.
Arch Virol Suppl ; 9: 41-50, 1994.
Article in English | MEDLINE | ID: mdl-8032271

ABSTRACT

We investigated the possibility of reconstructing the 2'-5' oligoadenylate (2-5A) pathway into the plant kingdom to achieve multiple virus resistance. Differently phosphorylated 2-5A trimers and tetramers inhibited TMV RNA translation in cell-free systems. In wheat germ extracts the most potent inhibitors were nonphosphorylated forms of 2-5A. Triphosphorylated forms of 2-5A were deposphorylated and hydrolysed in plant extracts. Since we could not detect homologous DNA to mammalian 2-5A synthetase cDNA in tobacco or potato, we cloned rat 2-5A synthetase cDNA and transformed it by the Agrobacterium-mediated mechanism into tobacco and potato. Transformed tobacco plants were resistant to PVS infection and propagation of PVX was reduced. In transgenic potatoes tolerance to PVX and, in one transgenic clone, also to PVY was observed.


Subject(s)
2',5'-Oligoadenylate Synthetase/genetics , Oligonucleotides/pharmacology , Plant Diseases , Plant Viruses/drug effects , Plants, Genetically Modified/enzymology , Animals , Endoribonucleases/analysis , Immunity, Innate , Models, Biological , Oligonucleotides/metabolism , Plant Viruses/pathogenicity , Plants, Toxic , RNA, Viral/drug effects , Rats , Solanum tuberosum , Nicotiana , Tobacco Mosaic Virus/drug effects
6.
Biotechnology (N Y) ; 11(9): 1048-52, 1993 Sep.
Article in English | MEDLINE | ID: mdl-7764002

ABSTRACT

We cloned and sequenced a rat cDNA encoding the 2'-5' oligoadenylate synthetase, a component of the mammalian interferon-induced antiviral response, and used Agrobacterium-mediated transformation to generate transgenic potato clones expressing this mammalian enzyme. In transgenic plants infected with potato virus X and followed under field conditions, virus concentrations in leaves and in tubers were significantly lower than in nontransgenic controls. Additionally, virus concentration in the leaves of five transgenic clones and in tubers of one clone was also lower than in transgenic potatoes expressing potato virus X coat protein.


Subject(s)
2',5'-Oligoadenylate Synthetase/genetics , Plant Viruses/growth & development , Solanum tuberosum/genetics , 2',5'-Oligoadenylate Synthetase/chemistry , Amino Acid Sequence , Animals , Blotting, Northern , Blotting, Southern , DNA/chemistry , DNA/genetics , Gene Expression , Mice , Molecular Sequence Data , Plants, Genetically Modified , Plasmids , Rats , Sequence Homology , Solanum tuberosum/enzymology , Solanum tuberosum/microbiology , Transfection
7.
Plant Mol Biol ; 22(2): 183-93, 1993 May.
Article in English | MEDLINE | ID: mdl-8507822

ABSTRACT

We are approaching corolla differentiation in Compositae by studying the regulation of flavonoid pathway genes during inflorescence development in gerbera. We have cloned a dfr cDNA from a ray floret corolla cDNA library of Gerbera hybrida var. Regina by a PCR technique based on homologies found in genes isolated from other plant species. The functionality of the clone was tested in vivo by complementing the dihydrokaempferol accumulating petunia mutant line RL01. By Southern blot analysis, G. hybrida var. Regina was shown to harbour a small family of dfr genes, one member of which was deduced to be mainly responsible for the DFR activity in corolla. Dfr expression in corolla correlates with the anthocyanin accumulation pattern: it is basipetally induced, epidermally specific and restricted to the ligular part of corolla. By comparing the dfr expression in different floret types during inflorescence development, we could see that dfr expression reflects developmental schemes of the outermost ray and trans florets, contrasted with that of the disc florets.


Subject(s)
Alcohol Oxidoreductases/genetics , Gene Expression Regulation , Genes, Plant/genetics , Plants/genetics , Amino Acid Sequence , Base Sequence , Cloning, Molecular , Flavonoids/metabolism , In Situ Hybridization , Molecular Sequence Data , Plant Development , Plants, Genetically Modified/genetics , RNA, Messenger/genetics , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Time Factors , Tissue Distribution
8.
DNA ; 6(3): 179-87, 1987 Jun.
Article in English | MEDLINE | ID: mdl-3595418

ABSTRACT

A complementary DNA (cDNA) encoding ornithine decarboxylase was isolated from a human liver cDNA library, and the nucleotide sequence coding for the entire enzyme was determined. The 1825-nucleotide-long cDNA contained an open reading frame of 1383 nucleotides, 87 nucleotides 5' from the first methionine codon, 346 nucleotides in the 3'-noncoding region, and a poly(A) tail of nine bases. Primer extension studies indicated that the 5'-noncoding region of the human ornithine decarboxylase mRNA was 335 nucleotides long. The amino acid sequence deduced from the open reading frame for a 461-residue polypeptide predicts a molecular weight of 51.156 for the human enzyme and has about 90% homology with the amino acid sequence of the murine ornithine decarboxylase (44 differences among the 461 amino acids). The nucleotide sequences of the human and murine ornithine decarboxylase mRNAs share an 85% homology, even in their 3'-noncoding regions. In contrast to rodent tissues with two ornithine decarboxylase mRNAs, normal human tissues appear to express only a single mRNA species with a molecular size of 2.25 kb. Southern blotting of human leukocyte DNA from 20 individuals indicated that the ornithine decarboxylase gene belongs to a multigene family in man and showed restriction fragment length polymorphism when cleaved with Pst I, but not when cleaved with Pvu II, Msp I, Hinc II, or Bam HI.


Subject(s)
DNA/genetics , Ornithine Decarboxylase/genetics , Amino Acid Sequence , Animals , Base Sequence , Cell Line , DNA, Recombinant , Humans , Mice/genetics , Neoplasm Proteins/genetics , Neuroblastoma/enzymology , Neuroblastoma/genetics , RNA, Messenger/genetics , Sequence Homology, Nucleic Acid
9.
Proc Natl Acad Sci U S A ; 83(3): 594-8, 1986 Feb.
Article in English | MEDLINE | ID: mdl-3456155

ABSTRACT

Ornithine decarboxylase (OrnDCase; L-ornithine carboxy-lyase, EC 4.1.1.17) mRNA present in mouse kidney comprises two species with molecular sizes of approximately 2.2 and approximately 2.7 kilobases (kb). cDNA clones prepared from murine kidney OrnDCase mRNA were used to determine the reason for the size heterogeneity of these mRNAs. Two of the cDNA clones (pODC16 and pODC74) that differed at the 3' termini were isolated and sequenced. DNA sequencing indicated that each cDNA had a poly(A) tail; however, pODC74 was 429 nucleotides longer than pODC16 at the 3' end and contained two AATAAA signals for poly(A) addition. That the longer cDNA corresponded to the larger mRNA was confirmed by hybridization of a unique Pst I/Pst I fragment from the 3' terminus of pODC74 only to the 2.7-kb OrnDCase mRNA. The two cDNAs did not represent full-length copies of OrnDCase mRNAs and were 1199 (pODC16) and 1204 base pairs (bp) (pODC74) long. There were five mismatches in their 759-bp-long overlapping nucleotide sequence, suggesting that the 2.2- and 2.7-kb OrnDCase mRNAs may be products of two separate, yet very similar, OrnDCase genes. Androgen regulation of the accumulation of these two OrnDCase mRNAs appeared to occur coordinately, as testosterone administration brought about comparable increases in their concentrations in mouse kidney.


Subject(s)
Kidney/enzymology , Ornithine Decarboxylase/genetics , RNA, Messenger/genetics , Amino Acid Sequence , Androgens/physiology , Animals , Base Sequence , Cloning, Molecular , DNA/genetics , Female , Male , Mice , Ornithine Decarboxylase/biosynthesis
11.
Cytogenet Cell Genet ; 42(3): 133-40, 1986.
Article in English | MEDLINE | ID: mdl-3755388

ABSTRACT

Using a mouse cDNA probe for ornithine decarboxylase (ODC), we have identified and isolated an ODC cDNA clone from a lambda gt11 recombinant library prepared from human liver cell mRNA. The 2.0-kb insert of this clone hybridizes with several mouse genomic ODC DNA restriction fragments under conditions of low stringency, but reacts with only few human DNA fragments and a polyA+ RNA species of 2.2 kb under both nonstringent and stringent hybridization conditions. This suggests that, unlike the mouse genome, there are only few ODC genes in the human genome. The human ODC DNA fragments segregate with chromosome regions 2pter----p23 and 7cen----qter in mouse X human somatic cell hybrid clones containing normal, translocated, and deleted human chromosomes. Sequences of the short arm of chromosome 2 containing the NMYC oncogene at 2p23----p24 are often involved in DNA amplification in neuroblastomas and small-cell lung cancers. However, in at least three cases--one neuroblastoma cell line, one neuroblastoma tumor, and one lung carcinoma--the ODC sequences are not coamplified with the NMYC oncogene.


Subject(s)
Chromosome Mapping , Chromosomes, Human, 1-3 , Chromosomes, Human, 6-12 and X , Gene Amplification , Oncogenes , Ornithine Decarboxylase/genetics , Animals , Base Sequence , DNA/genetics , DNA, Neoplasm/genetics , Humans , Hybrid Cells , Mice , Neuroblastoma/genetics , Nucleic Acid Hybridization
12.
Biochem Biophys Res Commun ; 126(2): 734-40, 1985 Jan 31.
Article in English | MEDLINE | ID: mdl-2983688

ABSTRACT

Stepwise increments of the concentration of 2-difluoromethylornithine, a mechanism-based irreversible inhibitor of mammalian ornithine decarboxylase (EC 4.1.1.17), resulted in a selection of cultured Ehrlich ascites carcinoma cells capable of growing in the presence of up to 50 mM difluoromethylornithine. Dialyzed extracts of drug-resistant tumor cells exhibited a very high ornithine decarboxylase activity and contained large excess of immunoreactive ornithine decarboxylase protein. Hybridization analyses with cloned complementary DNA revealed that the difluoromethylornithine-resistant tumor cells also expressed mRNA of the enzyme at greatly enhanced rate. The overproduction of ornithine decarboxylase by the tumor cells grown under the pressure of difluoromethylornithine was at least partly attributable to a 10 to 20-fold increase in the total gene dosage of ornithine decarboxylase involving an amplification of several genes of the gene family. The gene amplification developed appeared to be stable, as the gene dosage only slowly (during a period of several months) returned towards the normal level upon the removal of difluoromethylornithine. The overproduction of ornithine decarboxylase was accompanied by an enhanced resistance of the enzyme towards difluoromethylornithine in vitro.


Subject(s)
Carcinoma, Ehrlich Tumor/enzymology , Gene Amplification/drug effects , Ornithine Decarboxylase/genetics , Ornithine/analogs & derivatives , Animals , Base Sequence , Cells, Cultured , DNA , DNA Restriction Enzymes , Deoxyribonuclease EcoRI , Drug Resistance , Eflornithine , Mice , Nucleic Acid Hybridization , Ornithine/pharmacology , Ornithine Decarboxylase/biosynthesis
13.
Endocrinology ; 116(1): 226-33, 1985 Jan.
Article in English | MEDLINE | ID: mdl-3964747

ABSTRACT

The mechanisms by which nonsteroidal antiandrogens such as flutamide (alpha, alpha, alpha-trifluoro-2-methyl-4'-nitro-m-propionotoluidide) influence androgen receptor distribution and androgen-regulated gene expression are poorly understood. Therefore, we studied acute and long-term effects of flutamide, administered alone or in combination with testosterone, on androgen receptor dynamics in mouse kidney. Nuclear androgen receptors were measured using 5 mM pyridoxal 5'-phosphate extracts of renal nuclei isolated with the hexylene glycol method. Androgen-regulated ornithine decarboxylase (ODC) and ODC-messenger RNA were used as biological markers for hormone action. A single dose of flutamide increased the measurable concentration of renal nuclear androgen receptors in a dose-dependent manner by 1 h after treatment, although to a lesser extent than a comparable dose of testosterone. When 5 mg flutamide was given concomitantly with a submaximal dose of testosterone (0.1 mg), nuclear androgen receptor concentration was similar to that achieved with flutamide alone; this inhibitory effect of the antiandrogen was reversed by a 10-fold higher dose of testosterone. The influence of flutamide on the steady-state receptor levels in renal nuclei achieved by continuous androgen administration was investigated by giving a single dose of this compound to mice with testosterone-releasing implants. In these animals, flutamide administration decreased nuclear androgen receptor concentration with an initial half-life of about 3.3 h. This half-life was similar to that after cycloheximide administration, but significantly longer than that measured (1.3 h) upon removal of the implant. During treatment of female mice for 8 days with testosterone-releasing implants (40 micrograms/day), both the immunoreactive and catalytically active ODC concentration increased about 300-fold. In contrast, there was no stimulation of ODC during the prolonged administration of flutamide, although this treatment resulted in a dose-dependent increase in the nuclear androgen receptor concentration. However, flutamide (up to 650 micrograms/day) given concomitantly with testosterone (40 micrograms/day) almost completely abolished the testosterone-induced increase in ODC. The changes in ODC-messenger RNA concentration, as measured by hybridization to a complementary DNA probe, paralleled those of the enzyme protein suggesting that flutamide action involves inhibition of transcription of androgen-regulated gene(s). We conclude that 1) nuclear androgen receptor turnover in mouse kidney is a relatively rapid process and 2) nonsteroidal antiandrogens such as flutamide have an intrinsic ability to form


Subject(s)
Anilides/pharmacology , Flutamide/pharmacology , Gene Expression Regulation/drug effects , Kidney/metabolism , Ornithine Decarboxylase/genetics , Receptors, Androgen/metabolism , Receptors, Steroid/metabolism , Animals , Cell Nucleus/metabolism , Cycloheximide/pharmacology , Female , Kidney/drug effects , Male , Mice , Nucleic Acid Hybridization , RNA, Messenger/metabolism , Rats , Rats, Inbred Strains , Receptors, Androgen/drug effects , Testosterone/pharmacology
15.
Biochem J ; 221(2): 483-8, 1984 Jul 15.
Article in English | MEDLINE | ID: mdl-6433883

ABSTRACT

Glyoxal bis(guanylhydrazone), the parent compound of methylglyoxal bis(guanylhydrazone), was synthesized and tested for its ability to inhibit the biosynthesis of polyamines. It was found to be a powerful competitive inhibitor of adenosylmethionine decarboxylase (EC 4.1.1.50), yet the lack of the methyl group at the glyoxal portion increased the apparent Ki value for the enzyme by about 30-fold in comparison with methylglyoxal bis(guanylhydrazone). Glyoxal bis(guanylhydrazone) inhibited diamine oxidase (EC 1.4.3.6) activity as effectively as did methylglyoxal bis(guanylhydrazone). The cellular accumulation curves of glyoxal bis(guanylhydrazone) in L1210 cells were practically superimposable with those of methylglyoxal bis(guanylhydrazone), and the uptake of both compounds was distinctly stimulated by a prior treatment with 2-difluoromethylornithine. The drug decreased the concentration of spermidine in a dose-dependent manner and, in contrast with methylglyoxal bis(guanylhydrazone), without a concomitant accumulation of putrescine. The fact that putrescine concentrations were decreased in cells exposed to glyoxal bis(guanylhydrazone) was, at least in part, attributable to an inhibition of ornithine decarboxylase (EC 4.1.1.17) activity in cells treated with the compound. Under these experimental conditions equivalent concentrations of methylglyoxal bis(guanylhydrazone) [1,1'-[(methylethanediylidine)dinitrilo]diguanidine] elicited large increases in the enzyme activity. When combined with difluoromethylornithine, glyoxal bis(guanylhydrazone) potentiated the growth-inhibitory effect of that drug. Taking into consideration the proven anti-leukaemic activity of glyoxal bis(guanylhydrazone), its effectiveness to inhibit spermidine biosynthesis (without raising the concentration of putrescine) as well as its suitability for combined use with inhibitors of ornithine decarboxylase, this drug is apparently worthy of further testing in tumour-bearing animals, especially in combination with difluoromethylornithine or related inhibitors of ornithine decarboxylase.


Subject(s)
Guanidines/pharmacology , Mitoguazone/pharmacology , Polyamines/metabolism , Adenosylmethionine Decarboxylase/antagonists & inhibitors , Amine Oxidase (Copper-Containing)/antagonists & inhibitors , Animals , Carcinoma, Ehrlich Tumor/enzymology , Cells, Cultured , DNA, Neoplasm/metabolism , Eflornithine , Female , Leukemia L1210/metabolism , Mice , Mitoguazone/analogs & derivatives , Neoplasm Proteins/biosynthesis , Ornithine/analogs & derivatives , Ornithine/pharmacology
16.
Biochem Biophys Res Commun ; 120(1): 9-14, 1984 Apr 16.
Article in English | MEDLINE | ID: mdl-6712703

ABSTRACT

Methylglyoxal bis(guanylhydrazone) (MGBG), an inhibitor of spermidine and spermine biosynthesis and clinically used anti-cancer drug, powerfully inhibited carnitine-dependent fatty acid oxidation in heart muscle homogenates. Equipotent inhibition was also produced by spermine whereas spermidine and putrescine were less effective. MGBG appeared to act as a competitive inhibitor in respect to carnitine. Even though MGBG and spermine equally effectively depressed palmitate oxidation in muscle homogenates in vitro, a striking difference existed between the compounds as regards their effects on fatty acid oxidation in cultured tumor cells. Micromolar concentrations of MGBG distinctly impaired palmitate utilization also in cultured L 1210 leukemia cells, whereas similar concentrations of spermine markedly enhanced the oxidation of the fatty acid. The inhibitory effect of MGBG in cultured tumor cells was, at least partly, reversed upon addition of exogenous carnitine. The finding indicating that MGBG impairs fatty acid utilization may be an explanation for the known hypoglycemic effect produced by the drug in most animal species as well as for some of the side-effects associated with its clinical use, most notably severe myalgia.


Subject(s)
Fatty Acids/metabolism , Guanidines/pharmacology , Mitoguazone/pharmacology , Animals , Carnitine/pharmacology , In Vitro Techniques , Leukemia L1210/metabolism , Male , Mice , Myocardium/metabolism , Oxidation-Reduction/drug effects , Palmitates/metabolism , Rats , Rats, Inbred Strains
17.
Biochim Biophys Acta ; 803(4): 331-7, 1984 Apr 16.
Article in English | MEDLINE | ID: mdl-6322861

ABSTRACT

Ethylglyoxal bis(guanylhydrazone), a close derivative of the known anti-cancer drug methylglyoxal bis(guanylhydrazone), is also a powerful inhibitor of S-adenosylmethionine decarboxylase (EC 4.1.1.50), the enzyme needed for the synthesis of spermidine and spermine. There were, however, marked differences between the ethyl and methyl derivatives of glyoxal bis(guanylhydrazone) when tested in cultured L1210 cells. The cellular accumulation of ethylglyoxal bis(guanylhydrazone) represented only a fraction (20-25%) of that of the methyl derivative. Moreover, polyamine depletion, which is known to strikingly stimulate the uptake of methylglyoxal bis(guanylhydrazone), decreased, if anything, the uptake of ethylglyoxal bis(guanylhydrazone) by L1210 cells. The compound produced spermidine and spermine depletion fully comparable to that achieved with methylglyoxal bis(guanylhydrazone) at micromolar concentrations. Ethylglyoxal bis(guanylhydrazone) was growth-inhibitory to L1210 cells and produced an additive antiproliferative action when used together with 2-difluoromethylornithine. Ethylglyoxal bis(guanylhydrazone) was distinctly less effective than methylglyoxal bis(guanylhydrazone) in releasing bound polyamines from isolated cell organelles in vitro. Ethylglyoxal bis(guanylhydrazone) was also devoid of the early and profound mitochondrial toxicity typical to methylglyoxal bis(guanylhydrazone). These findings may indicate that this compound is a more specific inhibitor of polyamine biosynthesis with less intracellular polyamine 'receptor-site' activity than methylglyoxal bis(guanylhydrazone).


Subject(s)
Guanidines/pharmacology , Leukemia L1210/metabolism , Mitoguazone/pharmacology , Polyamines/metabolism , Adenosylmethionine Decarboxylase/antagonists & inhibitors , Animals , Cell Division/drug effects , Microscopy, Electron , Mitochondria/drug effects , Mitoguazone/analogs & derivatives , Mitoguazone/metabolism , Receptors, Cell Surface/drug effects , Spermidine/biosynthesis , Spermine/biosynthesis
18.
Cancer Lett ; 18(1): 1-10, 1983 Feb.
Article in English | MEDLINE | ID: mdl-6402294

ABSTRACT

Mice were treated with daily injections of methylglyoxal bis(guanyl-hydrazone) (MGBG) without or with concurrent administration of 2-difluoromethylornithine (DFMO) in drinking water for 15 days. Analysis of 10 different tissues for their MGBG content during the treatment revealed little evidence for a tissue specific cumulative accumulation of the drug given either alone or in combination with DFMO. On the contrary, tissue MGBG levels tended to increase until the 4th to 7th day of the treatment, whereafter a gradual decline or a plateau was obvious in most tissues. The concomitant DFMO treatment produced a consistent elevation of tissue MGBG concentrations in bone marrow cells and possibly also in intestinal tissue. In L1210 leukemia-bearing DBA mice, MGBG was most actively taken up by the ascitic leukemia cells. A priming of the tumor-bearing mice with DFMO for a few days before the start of MGBG injections resulted in a strikingly enhanced accumulation of the latter drug in the leukemia cells and also in the spleen, which was apparently heavily infiltrated by tumor cells. In liver, small intestine and in bone marrow cells of tumor-bearing animals the concentration of MGBG was not influenced by the DFMO treatment. In DBA mice without the L1210 tumor, DFMO only insignificantly increased the level of MGBG in bone marrow cells whereas no increase was seen in the spleen, in contrast to the same organ obtained from tumor-bearing mice. This combined treatment, in comparison with DFMO or MGBG alone, also produced the best therapeutic response as revealed by marked reduction of the tumor mass.


Subject(s)
Antineoplastic Agents/administration & dosage , Guanidines/metabolism , Leukemia L1210/metabolism , Mitoguazone/metabolism , Ornithine/analogs & derivatives , Animals , Bone Marrow/metabolism , Drug Therapy, Combination , Eflornithine , Female , Leukemia L1210/drug therapy , Mice , Mice, Inbred DBA , Mitoguazone/administration & dosage , Ornithine/administration & dosage , Ornithine/pharmacology , Spleen/metabolism , Time Factors , Tissue Distribution
20.
Cancer Res ; 43(1): 324-7, 1983 Jan.
Article in English | MEDLINE | ID: mdl-6401167

ABSTRACT

Treatment of mice with DL-alpha-difluoromethylornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase (EC 4.1.1.17), produced a significant spermidine depletion in liver, small intestine, and bone marrow among eight tissues studied. The accumulation of methylglyoxal bis(guanylhydrazone) (MGBG) was selectively enhanced in small intestine and in bone marrow cells in response to a prior DFMO treatment. In other tissues studied, i.e., brain, skeletal and cardiac muscle, liver, kidney, and spleen, a preceding treatment with DFMO had no effect on the accumulation of subsequently injected MGBG. When mice, primed with DFMO and then treated with a single injection of MGBG, were given nontoxic doses of spermidine or putrescine through a gastric tube, high concentrations of MGBG in the small intestine and in bone marrow cells were effectively reduced. In spite of the route of administration, bone marrow cells appeared to be more sensitive than intestinal tissue as regards the prevention of the tissue accumulation of MGBG by the polyamines. The different sensitivity of various tissues to the natural polyamines in this respect may offer a means to develop a tissue-specific "polyamine rescue concept" to be used in connection with MGBG treatment.


Subject(s)
Carboxy-Lyases/antagonists & inhibitors , Guanidines/metabolism , Mitoguazone/metabolism , Ornithine Decarboxylase Inhibitors , Ornithine/analogs & derivatives , Polyamines/metabolism , Animals , Bone Marrow/metabolism , Eflornithine , Intestine, Small/metabolism , Liver/metabolism , Mice , Ornithine/pharmacology , Polyamines/pharmacology , Tissue Distribution
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