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1.
Acta Physiol Hung ; 102(2): 197-205, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26100309

ABSTRACT

UNLABELLED: Left atrial (LA) distension has been demonstrated to be linked with aortic stiffness in different patient populations. Three-dimensional (3D) speckle-tracking echocardiography (STE) seems to be a promising tool for volumetric and functional evaluation of the LA. The aim of the present study was to determine whether correlations exist between 3DSTE-derived LA volume-based and strain parameters characterizing all phasic functions of the LA and echocardiographic aortic elastic properties in healthy subjects. The study included 19 healthy volunteers (mean age: 37.9 ± 11.4 years, 11 men) who had undergone complete two-dimensional (2D) Doppler transthoracic echocardiography extended with the assessment of aortic elastic properties and 3DSTE. RESULTS: None of LA volumes correlated with echocardiographic aortic elastic properties. Active atrial stroke volume correlated with aortic stiffness index (ASI, r = 0.45, p = 0.05). None of other volume-based functional properties significantly correlated with aortic stiffness parameters. Global peak 3D strain correlated with aortic strain (r = ‒0.46, p = 0.05). global radial pre-atrial contraction strain correlated with ASI (r = ‒0.49, p = 0.04) and AS (r = ‒0.50, p = 0.04). CONCLUSIONS: Correlations exist between 3DSTE-derived LA functional parameters and eschocardiographic aortic elastic properties in healthy subjects.


Subject(s)
Aorta/diagnostic imaging , Atrial Function, Left , Echocardiography, Three-Dimensional , Heart Atria/diagnostic imaging , Vascular Stiffness , Adult , Biomechanical Phenomena , Echocardiography, Doppler , Elasticity , Female , Healthy Volunteers , Humans , Male , Middle Aged , Predictive Value of Tests , Ventricular Function, Left
2.
Neuroscience ; 152(4): 1040-53, 2008 Apr 09.
Article in English | MEDLINE | ID: mdl-18355967

ABSTRACT

We have expressed A-FOS, an inhibitor of activator protein-1 (AP-1) DNA binding, in adult mouse striatal neurons. We observed normal behavior including locomotion and exploratory activities. Following a single injection of cocaine, locomotion increased similarly in both the A-FOS expressing and littermate controls. However, following repeated injections of cocaine, the A-FOS expressing mice showed increased locomotion relative to littermate controls, an increase that persisted following a week of withdrawal and subsequent cocaine administration. These results indicate that AP-1 suppresses this behavioral response to cocaine. We analyzed mRNA from the striatum before and 4 and 24 h after a single cocaine injection in both A-FOS and control striata using Affymetrix microarrays (430 2.0 Array) to identify genes mis-regulated by A-FOS that may mediate the increased locomotor sensitization to cocaine. A-FOS expression did not change gene expression in the basal state or 4 h following cocaine treatment relative to controls. However, 24 h after an acute cocaine treatment, 84 genes were identified that were differentially expressed between the A-FOS and control mice. Fifty-six genes are down-regulated while 28 genes are up-regulated including previously identified candidates for addiction including brain-derived neurotrophic factor and period homolog 1. Using a random sample of identified genes, quantitative PCR was used to verify the microarray studies. The chromosomal location of these 84 genes was compared with human genome scans of addiction to identify potential genes in humans that are involved in addiction.


Subject(s)
Cocaine-Related Disorders/genetics , Cocaine/pharmacology , Dopamine Uptake Inhibitors/pharmacology , Gene Expression Regulation/drug effects , Replication Protein C/metabolism , Age Factors , Animals , Animals, Newborn , Behavior, Animal/drug effects , Chromosome Mapping/methods , Cocaine-Related Disorders/physiopathology , Corpus Striatum/drug effects , Dose-Response Relationship, Drug , Exploratory Behavior/drug effects , Gene Expression Regulation/genetics , Locomotion/drug effects , Mice , Mice, Transgenic , Microarray Analysis/methods , Phosphopyruvate Hydratase/genetics , Phosphopyruvate Hydratase/metabolism , RNA, Messenger/metabolism , Replication Protein C/genetics , Time Factors
3.
Article in English | MEDLINE | ID: mdl-12696421

ABSTRACT

We investigated the individual number change of Empoasca spp. cicadas species that are living in potatoes for 3 years. We applied the "100 plants" method for the determination for the individual number once per week. Based on the data determined that the settling of adult begins on the last days of May, and valid presence will be followed till the end of the breeding-season. The individual number was gradually increased during the settling, and reached the peak in 1990 on 23 July, in 2000 on 6 August and in 2001 on 22 July. We determined the individuals gathered during the collection. In the population of Empoasca spp. The E. solani Curtis and the E. decipiens Paoli played the dominant role. The E. vitis Göthe was also present with insignificant individual number. Beside the adults many larvae and nymphs were living on the potato which means that the Empoasca spp. Can reproduce also on the potato. At the time of peak individual number in 1999 1876 larvae, 344 nymphs and 400 adults were present on 100 plants, in 2000 (according to the previous order) 3340, 580, 1280, and in 2001 there were 954, 786 and 285. The rainfall in Hungary was disadvantageous in the investigated period, especially the year 2000. During the rain-free period the temperature was high and the relative humidity of the air was low. However, we could state that the increase of the cicada individual number was not restrained by the heat (30-35 degrees C) days. The decrease was in connection with the ageing of the plant stock.


Subject(s)
Entomology/methods , Hemiptera/growth & development , Solanum tuberosum/parasitology , Animals , Hemiptera/classification , Humidity , Hungary , Larva/growth & development , Nymph/growth & development , Rain , Temperature
4.
Orv Hetil ; 142(39): 2149-51, 2001 Sep 30.
Article in Hungarian | MEDLINE | ID: mdl-11723835

ABSTRACT

The authors aim is to draw the readers attention to the possible occurrence of endometrial carcinoma in the young, by presenting the case of a 23 year-old woman. They highlight the risk factors (obesity, anovulatory bleeding abnormality, hypertension, positive familial history), that may have lead to the development of the endometrial carcinoma of their patient. It is assumed, that bleeding abnormality of a young woman could be the first sign of the carcinoma of the uterine corpus. They consider it obligatory in similar cases to: 1. Perform a throughout investigation of the endocrinological status 2. Measure the thickness of the endometrium with ultrasound 3. Histological examination 4. Careful follow up.


Subject(s)
Carcinoma/diagnosis , Endometrial Neoplasms/diagnosis , Adult , Carcinoma/etiology , Endometrial Neoplasms/etiology , Female , Humans , Obesity/complications , Risk Factors
5.
Prostate ; 41(3): 203-7, 1999 Nov 01.
Article in English | MEDLINE | ID: mdl-10517879

ABSTRACT

BACKGROUND: Hox genes encode transcriptional regulatory proteins that are largely responsible for establishing the body plan of all metazoan organisms. A subset of Hox genes is expressed during the period of organogenesis and into adulthood. hoxb-13 is a recently-described member of the Hox gene family that is expressed in the spinal cord, hindgut, and urogenital sinus during embryogenesis. METHODS: Northern blot and in situ hybridization analyses of hoxb-13 expression in adult mouse tissues were performed. RESULTS: hoxb-13 mRNA is restricted to the prostate gland and distal colon in adult animals. In situ hybridization of mouse prostate tissue demonstrated that hoxb-13 is expressed in the epithelial cells of the ventral, dorsal, lateral, and anterior prostate lobes. Accumulation of hoxb-13 mRNA is not diminished following castration. CONCLUSIONS: These data demonstrate that hoxb-13 expression is androgen-independent in mouse prostate glands. The identification of hoxb-13 as an androgen-independent gene expressed in adult mouse prostate epithelial cells provides a new potential target for developing therapeutics to treat advanced prostate cancer.


Subject(s)
Androgens/pharmacology , Gene Expression Regulation , Genes, Homeobox/genetics , Homeodomain Proteins/genetics , Prostate/physiology , Animals , Blotting, Northern , Epithelial Cells/physiology , In Situ Hybridization , Male , Mice
6.
Peptides ; 19(9): 1519-23, 1998.
Article in English | MEDLINE | ID: mdl-9864058

ABSTRACT

Small cell lung cancer (SCLC) cells express a variety of neuropeptides which act as autocrine growth factors. Although several neuropeptide analogs have been reported to antagonize SCLC proliferation, the development of these compounds has been limited by their low potency and the cytostatic nature of their effects. In the present study we evaluated the cytotoxic activity of four short-chain substance P analogs (NY3460, NY3238[-pHOPA], NY3238[Phe1], NY3238[Lys5]) against a panel of five SCLC cell lines. NY3460 was the most potent compound in all five SCLC cell lines (IC50 = 2.8-3.7 microM) as assessed by a MTT growth inhibitory assay. NY3238[Phe1] was also relatively active in all cell lines (IC50 = 3.5-11.2 microM), while NY3238[Lys5] and NY3238[-pHOPA] were substantially less active. NY3460 was the only agent to induce an increase in the percentage of cells with subdiploid DNA content suggestive of apoptosis by flow cytometric DNA content analysis. The induction of apoptosis was confirmed by fluorescent microscopy in NCI-H69, NCI-H82, NCI-H446, and NCI-H510 cells after exposure to 5.0 microM NY3460 for 48 h. These findings suggest that NY3460 is a relatively potent cytotoxic inhibitor of SCLC growth, and that short-chain neuropeptide analogs deserve further evaluation as anti-SCLC agents.


Subject(s)
Antineoplastic Agents, Hormonal/pharmacology , Apoptosis , Carcinoma, Small Cell , Lung Neoplasms , Substance P/analogs & derivatives , Flow Cytometry , Microscopy, Fluorescence , Substance P/pharmacology
7.
Mol Cell ; 2(1): 101-8, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9702196

ABSTRACT

The heat shock transcription factor HSF activates expression of its target genes in response to elevated temperatures and chemical or physiological stress. A key step in the activation process involves the formation of HSF homotrimers, leading to high-affinity DNA binding. The mechanism by which HSF trimerization and DNA binding is regulated by stress signals has remained elusive. Here, we report that trimerization and DNA binding of purified Drosophila HSF can be directly and reversibly induced in vitro by heat shock temperatures in the physiological range and by an oxidant, hydrogen peroxide. Other inducers of the heat shock response, including salicylate, dinitrophenol, ethanol, and arsenite, have no effect on HSF trimerization in vitro, indicating that these inducers act by indirect mechanisms.


Subject(s)
DNA-Binding Proteins/physiology , Drosophila melanogaster/physiology , Hot Temperature , Insect Proteins/physiology , Oxidative Stress , Adaptation, Physiological , Animals , Cells, Cultured , DNA/metabolism , DNA-Binding Proteins/chemistry , Drosophila Proteins , Gene Expression Regulation , Heat Shock Transcription Factors , Hydrogen Peroxide/pharmacology , Insect Proteins/chemistry , Oxidation-Reduction , Protein Binding , Protein Conformation/drug effects , Transcription Factors
8.
J Pept Sci ; 4(8): 486-95, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9927255

ABSTRACT

Small cell lung cancer (SCLC) cell lines produce and secrete various peptide hormones, e.g. bombesin (BN)/gastrin releasing peptide (GRP) like peptides that are proposed to function as their autocrine growth factors. To inhibit the proliferative effect of these hormones we have synthesized short chain BN[7-14]-analogues replacing the C-terminal peptide bond by a methylene-amino (-CH2NH-) unit and introducing D-Phe or D-Ser into position 12. As several substance P (SP) analogues were found to inhibit the growth of SCLC cells, some short chain SP-analogues have been synthesized. (Pseudo)octapeptides were synthesized in solution, by fragment condensation using the DCC/HOPfp method. Fragments and SP-analogues were synthesized stepwise using pentafluorophenyl esters. The resistance to hydrolysis of the reduced peptide bond made permitted exact quantification of the Leupsi(CH2NH)Leu pseudopeptide in hydrolysates. The binding ability of both types of peptides to BN-receptors on Swiss 3T3 mouse fibroblast cells and their antiproliferative effect on NCI-H69 human SCLC cell line have been tested and compared with a short chain SP-antagonist pHOPA-D-Trp-Phe-D-Trp-Leu-Leu-NH2 (R) previously described as a potent inhibitor of SCLC proliferation. While BN-analogues showed weak activity in inhibition of proliferation of SCLC cells, SP-analogues 6: D-MePhe-D-Trp-Phe-D-Trp-Leu(psi)(CH2NH)-Leu-NH2 and 7: D-MePhe-DTrp-Phe-D-Trp-Leu-MPA, in spite of greatly diminished affinity towards the BN-receptor, inhibited SCLC proliferation more effectively than R (6: IC50 = 2 microM, 7: IC50 = 5 microM and R: IC50 = 10 microM). Moreover, 6 inhibited the respiratory activity of SK-MES 1 epithelial type of lung carcinoma cells in proliferating but not in the quiescent state, suggesting that the antiproliferative effect of these compounds is not due to simple cytotoxicity. These short chain analogues of SP might be promising candidates as therapeutic agents in the treatment of SCLC.


Subject(s)
Amides , Carcinoma, Small Cell/pathology , Lung Neoplasms/pathology , Peptides/chemical synthesis , 3T3 Cells , Amino Acid Sequence , Animals , Bombesin/analogs & derivatives , Bombesin/antagonists & inhibitors , Bombesin/chemistry , Bombesin/pharmacology , Cell Division/drug effects , Humans , Hydrolysis , Mice , Molecular Sequence Data , Substance P/analogs & derivatives , Substance P/chemistry , Substance P/pharmacology , Tumor Cells, Cultured
9.
Mol Cell Biol ; 16(12): 7018-30, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8943357

ABSTRACT

Heat shock transcription factor (HSF) is a multidomain protein that exists as a monomer under normal conditions and is reversibly induced upon heat shock to a trimeric state that binds to DNA with high affinity. The maintenance of the monomeric state is dependent on hydrophobic heptad repeats located at the amino- and carboxy-terminal regions which have been proposed to form an intramolecular coiled-coil structure. In a systematic deletion analysis to identify other regions of HSF that may be required to regulate its oligomeric state, we have found that local sequences encompassing the carboxy-terminal end of the DNA binding domain and a broad region of HSF between the heptad repeats also contribute to this regulation. Immunocytochemical analysis of mutant HSF proteins revealed a canonical motif required for nuclear localization. HSF proteins lacking the nuclear localization signal remain in the cytoplasm, but these HSFs nonetheless exhibit reversible heat stress-inducible trimerization. The results indicate that the signals that regulate HSF trimerization operate in both the nuclear and cytoplasmic compartments of the cell.


Subject(s)
Drosophila/genetics , Heat-Shock Proteins/genetics , Signal Transduction/genetics , Animals , Biological Transport , Cell Nucleus/genetics , Mutation
10.
Nucleic Acids Res ; 24(2): 367-74, 1996 Jan 15.
Article in English | MEDLINE | ID: mdl-8628664

ABSTRACT

The heat shock transcription factor (HSF) is constitutively expressed in Drosophila cells as an inactive monomer. Upon heat shock HSF undergoes trimerization and acquires high affinity DNA binding ability leading to specific interaction with its cognate elements in heat shock promoters. Here we show that the transactivation function of HSF is conferred by the extreme C-terminal region of the protein. Deletion analysis of HSF fragments fused to the GAL4 DNA-binding domain demonstrates that transactivation is dependent on HSF residues 610-691. This domain is located beyond the C-terminal heptad repeat (leucine zipper 4) whose presence or integrity is dispensable for transactivation. The transactivation domain is functional in the absence of heat shock and can be replaced by the extreme C-terminal region of human HSF1. The Drosophila and human HSF transactivation domains are both rich in hydrophobic and acidic residues and may be structurally conserved, despite limited sequence identity.


Subject(s)
DNA-Binding Proteins/genetics , Drosophila/genetics , Saccharomyces cerevisiae Proteins , Transcription Factors/genetics , Transcriptional Activation/genetics , Amino Acid Sequence , Animals , Base Sequence , Cell Line , Cell Nucleus/chemistry , DNA/metabolism , DNA-Binding Proteins/analysis , DNA-Binding Proteins/metabolism , Drosophila Proteins , Fungal Proteins/genetics , Heat Shock Transcription Factors , Heat-Shock Response , Humans , Molecular Sequence Data , Recombinant Fusion Proteins/metabolism , Transcription Factors/analysis , Transcription Factors/metabolism
12.
Int J Cancer ; 60(1): 82-7, 1995 Jan 03.
Article in English | MEDLINE | ID: mdl-7529212

ABSTRACT

Human small-cell lung-cancer cells (SCLC) produce and secrete gastrin-releasing peptide (GRP), the mammalian equivalent of bombesin (BN). There is some evidence to suggest that GRP is an autocrine regulator of SCLC cell growth. In the search for potent BN antagonists, several substance-P (SP) analogs were found to inhibit the growth of SCLC cells. We found that a known short-chain SP antagonist, pHOPA-DTrp-Phe-DTrp-Leu-Leu-NH2(NY3238), inhibits the binding of 125I-Tyr4-BN on Swiss 3T3 cell line expressing BN receptors, as well as the proliferation of NCI-H69 SCLC cells. In this study we tested several analogs of NY3238 and we found that NY3521 and NY3460 are more effective in inhibition of proliferation of SCLC cells but less potent in inhibition of binding of 125I-Tyr4-BN on Swiss 3T3 cells than NY3238. Furthermore, we detected specific binding of radiolabelled NY3238 even below 1 nM on NCI-H69 cells that could have been inhibited by SP and NY3460 rather than by BN. In addition to these in vitro studies, NY3460 proved to be effective in inhibiting the growth of NCI-H69 SCLC xenografts in nude mice in vivo. These analogs of NY3238 could be promising therapeutic agents in the treatment of SCLC.


Subject(s)
Carcinoma, Small Cell/drug therapy , Lung Neoplasms/drug therapy , Oligopeptides/pharmacology , Substance P/analogs & derivatives , Substance P/antagonists & inhibitors , 3T3 Cells , Amino Acid Sequence , Animals , Bombesin/antagonists & inhibitors , Carcinoma, Small Cell/metabolism , Carcinoma, Small Cell/pathology , Cell Division/drug effects , Female , Humans , Kinetics , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Mice , Mice, Inbred BALB C , Mice, Nude , Molecular Sequence Data , Neoplasm Transplantation , Oligopeptides/metabolism , Substance P/metabolism , Substance P/pharmacology , Transplantation, Heterologous , Tumor Cells, Cultured/drug effects
13.
Nat Struct Biol ; 1(9): 605-14, 1994 Sep.
Article in English | MEDLINE | ID: mdl-7634100

ABSTRACT

The solution structure of the DNA-binding domain of the Drosophila heat shock transcription factor, as determined by multidimensional multinuclear NMR, resembles that of the helix-turn-helix class of DNA-binding proteins. The domain comprises a four-stranded antiparallel beta-sheet, packed against a three-helix bundle. The second helix is significantly distorted and is separated from the third helix by an extended turn which is subject to conformational averaging on an intermediate time scale. Helix 3 forms a classical amphipathic helix with polar and charged residues exposed to the solvent. Upon titration with DNA, resonance shifts in the backbone and Asn and Gln side-chain amides indicate that helix 3 acts as the recognition helix of the heat shock transcription factor.


Subject(s)
DNA-Binding Proteins/chemistry , DNA/metabolism , Heat-Shock Proteins , Saccharomyces cerevisiae Proteins , Transcription Factors/chemistry , Amino Acid Sequence , Base Sequence , Binding Sites , Conserved Sequence , DNA-Binding Proteins/metabolism , Drosophila Proteins , Heat Shock Transcription Factors , Kluyveromyces/metabolism , Molecular Sequence Data , Oligodeoxyribonucleotides , Protein Structure, Tertiary , Sequence Homology, Amino Acid , Transcription Factors/metabolism
14.
Drug Alcohol Depend ; 32(2): 107-11, 1993 Apr.
Article in English | MEDLINE | ID: mdl-8508721

ABSTRACT

Cytosolic free Ca2+ functions as a main regulator of numerous cellular processes, including those implicated in synthesis, release and responsiveness of hormones and neurotransmitters are discussed. To examine whether a change in the intracellular free calcium ion concentration [Ca2+]i occurs associated with delirium tremens and related states we compared [Ca2+]i in peripheral blood mononuclear cells (PBMC) of alcoholic patients under withdrawal with that of non-alcoholic patients and of healthy controls. [Ca2+]i in PBMC of alcoholic patients was significantly higher (P < 0.001) compared to both control groups, suggesting that changes in [Ca2+]i may be relevant to increased excitability of the central nervous system. Increased [Ca2+]i in PBMC might be diagnostically valuable as a biological marker of alcohol dependency.


Subject(s)
Alcohol Withdrawal Delirium/blood , Alcoholism/rehabilitation , Calcium/blood , Monocytes/metabolism , Adult , Alcoholism/blood , Brain/metabolism , Cytosol/metabolism , Female , Humans , Male , Middle Aged
15.
Eur J Biochem ; 201(3): 653-9, 1991 Nov 01.
Article in English | MEDLINE | ID: mdl-1718749

ABSTRACT

The complex terminator region of the Escherichia coli rrnB gene was analyzed by subcloning the terminators T1 and T2 and the inverted repeats IR1 and IR2 individually, or in various combinations, in a normal or inverted orientation into a terminator probe vector. The in vivo terminating efficiency was assayed by measuring the galactokinase activity encoded by the downstream galK gene. Termination efficiencies of all fragments were compared in two constructs, differing in the presence or absence of readthrough translation over the investigated terminator signal. The following main conclusions were drawn. (a) T1 and T2 are both efficient terminators in isolated forms. (b) IR1 and IR2 have some terminating effect (much lower than the proper terminators), especially in the inverted orientation. Their presence modifies the effect of the proper terminators in a quite unpredictable way, especially if these regions are translated. (c) The terminators are not symmetrical; in the inverted orientation T1 is practically inactive and T2 termination is reduced. (d) Translation radically decreases the efficiency of the terminators. (e) Several sequences in the rrnB gene, upstream of the terminator region (one in the 16S RNA and one in the 5S RNA coding region), are very efficient in vivo terminators in the inverted orientation.


Subject(s)
Escherichia coli/genetics , Genes, Bacterial , RNA, Bacterial/genetics , RNA, Ribosomal/genetics , Terminator Regions, Genetic , Base Sequence , Galactokinase/genetics , Molecular Sequence Data , Plasmids , Promoter Regions, Genetic , Protein Biosynthesis
16.
Acta Microbiol Hung ; 38(1): 55-60, 1991.
Article in English | MEDLINE | ID: mdl-1810112

ABSTRACT

SmuE I, a type II restriction endonuclease, has been isolated from Streptococcus mutans serotype E, which is an isoschizomes of Ava II recognizes the palidromic pentanucleotide sequence 5' GG/W/CC 3'. Similarly to Ava II, SmuE I cleaves the sequence, G--G/W/CC, generating 5' protruding fragment termini.


Subject(s)
DNA, Viral/chemistry , Deoxyribonucleases, Type II Site-Specific/isolation & purification , Streptococcus mutans/enzymology , Base Sequence , Chromatography, Gel , Culture Media , DNA, Viral/metabolism , Deoxyribonucleases, Type II Site-Specific/chemistry , Deoxyribonucleases, Type II Site-Specific/metabolism , Electrophoresis, Agar Gel , Mutation , Plasmids , Restriction Mapping
17.
J Biotechnol ; 16(1-2): 49-55, 1990 Oct.
Article in English | MEDLINE | ID: mdl-1370011

ABSTRACT

We describe here the construction of a family of expression vectors, based on the P2 promoter of the Escherichia coli rrnB gene by removing regulatory sequences downstream of the Pribnow-box and replacing them with the lac operator. These vectors allow cloning of foreign genes in such a way that their products are synthesized either in the form of fusion proteins of different length, or without fusion partners, with or without the original translational initiation signals. One of the vectors contains a synthetic oligothreonine-coding sequence that helps to stabilize the product of the cloned gene. These vectors allow high-level regulated expression of foreign genes, even if their products are relatively short peptides.


Subject(s)
Escherichia coli/genetics , Gene Expression Regulation, Bacterial , Genetic Vectors , Plasmids , Promoter Regions, Genetic , Amino Acid Sequence , Base Sequence , Cloning, Molecular , DNA, Bacterial/chemistry , Molecular Sequence Data , Protein Biosynthesis , RNA, Bacterial/genetics , RNA, Ribosomal/genetics , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/genetics , Regulatory Sequences, Nucleic Acid , Restriction Mapping , Transcription, Genetic
18.
J Biotechnol ; 13(4): 243-50, 1990 Mar.
Article in English | MEDLINE | ID: mdl-1366558

ABSTRACT

A family of expression plasmid vectors were constructed by fusing the strong P2 promoter of the rrnB gene of Escherichia coli (coding for ribosomal RNA) to the lac operator, thereby eliminating regulatory sequences from the rrnB gene and placing the expression under lac repressor control. This promoter proved to be stronger in vivo than the well-known consensus tac promoter, and its strength could be further increased by converting the sequence to consensus. The stability of the recombinant proteins could be increased by fusion to various lengths of the N-terminal end of beta-galactosidase, or by inserting a synthetic oligonucleotide, coding for heptathreonine. A new method was developed for the stabilization of recombinant plasmids without antibiotic selection, based on the presence of an essential gene on the plasmid and its absence from the chromosome. The application of this method is illustrated by the example of a plasmid expressing human proinsulin.


Subject(s)
Cloning, Molecular/methods , Escherichia coli/genetics , Biotechnology , Escherichia coli/metabolism , Gene Expression Regulation, Bacterial , Genetic Vectors , Humans , Plasmids , Proinsulin/genetics , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Transcription, Genetic
19.
Comp Biochem Physiol B ; 94(3): 505-10, 1989.
Article in English | MEDLINE | ID: mdl-2695284

ABSTRACT

1. The volume fraction of autophagic vacuoles in liver parenchymal and exocrine pancreatic cells was smallest and the serum insulin level highest in the 24 hr prestarved mouse immediately after 3 hr feeding period. 2. The size of the autophagic vacuole and lysosome (dense body) compartments increased in both types of cells during 2-72 hr fasting parallel with decreasing serum insulin levels. 3. The protein content of the cells decreased and the DNA-based activity of acid phosphatase showed little change throughout fasting. The activity of cathepsin D increased during days 2 and 3 of food deprivation. 4. Vinblastine (50 mg/kg body wt) applied for the last 2 hr of different periods (2, 12, 24, 48 and 72 hr) of fasting decreased serum insulin level and increased the fractional cytoplasmic volume of autophagic vacuoles and dense bodies. This increase was smaller when the drug was applied shortly after feeding and much larger after prolonged fasting. The increase was more pronounced in the pancreatic than in the liver cells. 5. Our data show that the effect of vinblastine on the size of the autophagic-lysosomal compartment depends on the feeding status of the animals.


Subject(s)
Fasting/metabolism , Insulin/blood , Lysosomes/enzymology , Vinblastine/pharmacology , Acid Phosphatase/metabolism , Animals , Cathepsin D/metabolism , Cytoplasmic Granules/metabolism , Lipoproteins/metabolism , Liver/cytology , Liver/enzymology , Lysosomes/drug effects , Male , Mice , Microscopy, Electron/methods , Pancreas/cytology , Pancreas/enzymology , Proteins/metabolism
20.
Exp Clin Endocrinol ; 91(2): 183-90, 1988 May.
Article in English | MEDLINE | ID: mdl-3409969

ABSTRACT

The behaviour of insulin binding receptors is rather unelucidated in non-insulin-dependent diabetes mellitus of the young. Authors in continuing their previous work studied the behaviour of insulin binding receptors of erythrocytes and monocytes in 9 MODY patients. They observed that specific insulin binding of circulating blood cells was significantly decreased in all cases as compared to the controls despite of a good state of metabolism (in the case of erythrocytes 4.63 +/- 1.1% vs. 6.03 +/- 1.7%, p less than 0.05, in the case of monocytes 2.3 +/- 1.2% vs. 3.6 +/- 1.4%, p less than 0.05). The lower value of insulin binding resulted from the decrease of receptor concentrations (in the case of erythrocytes 2.36 +/- 0.78 pmol/l vs. 3.81 +/- 1.14 pmol/l, p less than 0.05).


Subject(s)
Diabetes Mellitus, Type 2/physiopathology , Receptor, Insulin/physiology , Adult , Diabetes Mellitus, Type 2/pathology , Erythrocytes/analysis , Erythrocytes/metabolism , Erythrocytes/ultrastructure , Female , Humans , Male , Monocytes/analysis , Monocytes/metabolism , Monocytes/ultrastructure
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