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Biomedical subjects

I Nagy

Publications and source records attributed to I Nagy.

At least 91 records · Page 5Linked to original sources
PubMed1995

A single cytochrome P-450 system is involved in degradation of the herbicides EPTC (S-ethyl dipropylthiocarbamate) and atrazine by Rhodococcus sp. strain NI86/21.

During atrazine degradation by Rhodococcus sp. strain N186/21, N-dealkylated metabolites and an hydroxyisopropyl derivative are produced. The cytochrome P-450 system that is involved in degradation of thiocarbamate herbicides by strain N186/21 (I. Nagy, G. Schoofs, F. Compernolle, P. Proost, J. Vanderleyden, and R. De Mot, J. Bacteriol. 177:676-687, 1995) is also required for atrazine degradation. Atrazine-degrading activity was conferred on the atrazine-negative strains, mutant FAJ2027 of Rhodococcus sp. strain N186/21 and Rhodococcus erythropolis SQ1, upon transformation with the genes encoding the cytochrome P-450 system.

Alkylation↗
PubMed1995

Degradation of the thiocarbamate herbicide EPTC (S-ethyl dipropylcarbamothioate) and biosafening by Rhodococcus sp. strain NI86/21 involve an inducible cytochrome P-450 system and aldehyde dehydrogenase.

Determination of the N-terminal sequences of two EPTC (S-ethyl dipropylcarbamothioate)-induced proteins from thiocarbamate-degrading Rhodococcus sp. strain NI86/21 resolved by two-dimensional electrophoresis enabled the localization of the respective structural genes on two distinct DNA fragments. One of these strongly induced proteins is a NAD(+)-dependent dehydrogenase active on aliphatic aldehydes. The second protein was identified as a cytochrome P-450 enzyme. The cytochrome P-450 gene represents the first member of a new family, CYP116. Downstream of the cytochrome P-450 gene, two genes for a [2Fe-2S] ferredoxin (rhodocoxin) and a ferredoxin reductase are located. A putative regulatory gene encoding a new member of the AraC-XylS family of positive transcriptional regulators is divergently transcribed from the cytochrome P-450 gene. By hybridization, it was demonstrated that the aldehyde dehydrogenase gene is widespread in the Rhodococcus genus, but the components of the cytochrome P-450 system are unique to Rhodococcus sp. strain NI86/21. Overexpression in Escherichia coli was achieved for all of these proteins except for the regulatory protein. Evidence for the involvement of this cytochrome P-450 system in EPTC degradation and herbicide biosafening for maize was obtained by complementation experiments using EPTC-negative Rhodococcus erythropolis SQ1 and mutant FAJ2027 as acceptor strains. N dealkylation by cytochrome P-450 and conversion of the released aldehyde into the corresponding carboxylic acid by aldehyde dehydrogenase are proposed as the reactions initiating thiocarbamate catabolism in Rhodococcus sp. strain NI86/21. In addition to the major metabolite N-depropyl EPTC, another degradation product was identified, EPTC-sulfoxide.

Aldehyde Dehydrogenase↗
PubMed1995

Plasma amino acid concentration under human growth hormone treatment in uremic children.

The plasma amino acid concentrations were investigated before and after 3 and 30 months of human recombinant growth hormone treatment in 7 children with chronic renal failure. The concentrations of amino acids in plasma showed characteristic changes (pretreatment vs. after 3 and 30 months of treatment): Lys 113 +/- 33 vs. 162 +/- 27 and 109 +/- 38 mumol/l, Met 21 +/- 8 vs. 31 +/- 4 and 16 +/- 5, Thr 105 +/- 23 vs. 148 +/- 60 and 118 +/- 30, Ala 455 +/- 109 vs. 536 +/- 93 and 314 +/- 60, Gln 298 +/- 66 vs. 277 +/- 52 and 544 +/- 65, Glu 168 +/- 46 vs. 209 +/- 57 and 96 +/- 24, Gly 345 +/- 137 vs. 479 +/- 169 and 342 +/- 95, Pro 378 +/- 148 vs. 422 +/- 28 and 527 +/- 229, OH-Pro 33 +/- 17 vs. 105 +/- 23 and 97 +/- 35, Se 133 +/- 39 vs. 178 +/- 55 and 131 +/- 12 mumol/l. Long-term treatment with human recombinant growth hormone normalized plasma alanine, glutamine, and glutamic acid levels, increased the OH-Pro concentration, and did not alter the amino acid ratios of Gly/Val, Phe/Tyr, Ser/Gly, and Asn/Asp, but the Gln/Glu ratio approached the normal value.

Amino Acids↗
PubMed1995

Circulating ICAM-1 in alcoholic liver cirrhosis.

The intercellular adhesion molecule 1 (ICAM-1) level in the serum of patients with alcoholic liver cirrhosis was measured using a sandwich enzyme-linked immunosorbent assay. Circulating ICAM-1 was significantly elevated in the sera of all 19 patients as compared with normal healthy subjects. There was no correlation with the Child grade of the disease, but the highest levels of serum ICAM-1 (2,416 +/- 560 ng/ml) were measured in those patients who suffered from superimposed acute alcoholic hepatitis. No elevated serum ICAM-1 level was found in the ascitic fluid of cirrhotic patients. The elevated serum levels of ICAM-1 in patients with alcoholic liver diseases may provide useful diagnostic or prognostic information.

Adult↗
PubMed1995

A complex cerebrovascular screening system (CERBERUS).

Stroke is unique among neurological diseases since it has a high incidence rate, severe burden of illness, high economic cost, and it may be preventable [1]. Described here is a system for screening the cerebral and vascular status of individuals to detect the initial stages of vascular disorders. The computer based polygraphic system (CERBERUS) questions subjects about risk factors, stresses, neurologic symptoms and monitors impedance pulse waves of the head and extremities, EEG, and ECG. The system has been tested in 691 cases. Doppler control studies were carried out on approximately 300 of these cases. Additional somatic measures and psychological tests related to stroke risk factors were carried out for wide biological basis of possible correlation of CERBERUS data base. The high incidence of cerebrovascular disturbance was established by CERBERUS data, further confirmed by additional data gathered, and moreover was compared by traditional medical records. The polygraphic system is more sensitive at detecting physiological asymmetries of blood flow than even a Doppler measurements. This suggests that it may be a significantly improved means for the differential diagnosis of neurological disease and the screening of subjects for arteriosclerosis, transient ischemic attack and stroke prevention to be offered at the lowest level of medical service.

Adolescent↗
PubMed1995

Alcohol use, abuse, and alcohol-related disorders among ethnic groups in Hungary. Part I: Csángós from Egyházaskozár Region.

This paper reports the results of a study on alcohol drinking habits, alcohol-related acute symptoms, and alcohol abuse among Csángós, an ethnic minority in Hungary. The demographic data revealed their social characteristics: growing old, low education, endogamous marriages, early maternal age at birth of the first baby, and a high child number per family. Alcohol use survey revealed that alcohol consumption of the Csángós is considerably high; more than half of Csángó males and more than one-quarter of Csángó females are heavy drinkers. While all kinds of alcohol are consumed by males, wine drinking is more common among females. Acute reactions to a moderate dose of alcohol evoked a series of physical and physiological symptoms including facial flushing, higher pulse rate, tachycardia and euphoria among at least one third of the probands. There was a distinct gender difference in response to alcohol drinking. While a higher percentage of females reported intense skin flush (34%), a greater percentage of males reported symptoms such as sleepiness, euphoria and aggressiveness. The distribution of clinical chemical markers of alcohol abuse in the sera of the individuals under study confirmed heavier alcohol consumption among males than among females. Alcohol-related mortality data indicate liver cirrhosis and liver cancer as the leading cause of deaths among Csángó males. A high alcohol consumption among Csángó ethnic group reflects the acceptance of alcohol use in the community as an integral part of their lifestyle.

Adult↗
PubMed1994

NK1 and NK2 receptors contribute to C-fibre evoked slow potentials in the spinal cord.

Small diameter primary afferents produce slow synaptic potentials in spinal neurones. These can be recorded as prolonged ventral root potentials (VRPs) in the isolated neonatal rat spinal cord preparation. The VRP elicited by stimulating C-fibres consists of two phases: an early phase comprising a monosynaptic and a short polysynaptic response identical to that elicited by low threshold A beta fibres and a late phase which has an initial component (0.1-1 s) which is sensitive to N-methyl-D-aspartic acid receptor antagonism and a very long lasting second component (1-20 s) which is resistant to these antagonists. We now demonstrate that the slowest component of the VRP is significantly reduced by both NK1 and NK2 tachykinin receptor antagonists and as a consequence, tachykinins have a particular contribution to the cumulative depolarization produced by low frequency (1 Hz) C-fibre stimulation.

Amino Acid Sequence↗
PubMed1994

Cobalt accumulation in neurons expressing ionotropic excitatory amino acid receptors in young rat spinal cord: morphology and distribution.

Excitatory amino acids (EAA) acting on N-methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) and kainate receptors play an important role in synaptic transmission in the spinal cord. Quantitative autoradiography and physiological experiments suggest that NMDA receptors are localized mainly in lamina II while kainate and AMPA receptors are found on both dorsal and ventral horn neurons. However the cell types expressing EAA receptors and their laminar distribution is not known. We have used a cobalt uptake method to study the morphology and distribution of spinal cord neurons expressing AMPA, kainate, or NMDA excitatory amino acid receptors in the lumbar enlargement of the rat spinal cord. The technique involved superfusion of hemisected spinal cords of 14 day-old rat pups in vitro with excitatory amino acid receptor ligands in the presence of CoCl2. Cobalt has been shown to enter cells through ligand-gated ion channels in place of Ca2+. Cells which accumulated cobalt ions following activation by ionotropic excitatory amino acid receptors were visualized histochemically. The cobalt uptake generated receptor-specific labeling of cells, as the NMDA receptor antagonist D-(-)-2-amino-(5)-phosphonovaleric acid (D-AP-5) (20 microM) blocked the NMDA, but not kainate-induced cobalt uptake. The kainate-induced cobalt labeling was reduced by the non-selective excitatory amino acid receptor antagonist kynurenic acid (4 mM). Passive opening of the voltage-gated Ca(2+)-channels by KCl (50 mM) did not result in cobalt uptake, indicating that cobalt enters the cells through ligand-gated Ca(2+)-channels. AMPA (500 microM), kainate (500 microM), or NMDA (500 microM) each induced cobalt uptake with characteristic patterns and distributions of neuronal staining. Overall, kainate induced cobalt uptake in the greatest number of neuronal staining. Overall, kainate induced cobalt uptake in the greatest number of neuronal perikarya while NMDA-induced uptake was the lowest. AMPA and kainate, but not NMDA superfusion, resulted in cobalt labeling of glial cells. Our results show that the cobalt uptake technique is a useful way to study the morphology and distribution of cells expressing receptors with ligand-gated Ca2+ channels.

Animals↗
PubMed1994

Sequences of the cobalamin biosynthetic genes cobK, cobL and cobM from Rhodococcus sp. NI86/21.

Sequence analysis of a 5753-bp genomic fragment of Rhodococcus sp. NI86/21 revealed the presence of three homologues of known cobalamin biosynthetic genes. One of these genes encodes a protein showing strong homology with the precorrin-6x reductase (CobK) of Pseudomonas denitrificans. In addition, the rhodococcal homologue of the corrin methyltransferases, CobM from P. denitrificans and CbiF from Salmonella typhimurium, was identified. The protein deduced from a third Rhodococcus gene aligns well with CobL of P. denitrificans and with the protein pair CbiE/CbiT of S. typhimurium, which are involved in corrin methylation and decarboxylation.

Amino Acid Sequence↗
PubMed1994

Combination of cobalt labelling with immunocytochemical reactions for electron microscopic investigations on frog spinal cord.

Cobalt staining of primary afferents in frog spinal cord was combined with peroxidase-antiperoxidase pre-embedding or immunogold post-embedding immunocytochemical labelling. Our results have shown that cobalt labelling can easily be distinguished from both of the immunoreaction end products. The protocol of cobalt labelling did not affect the immunoreactivity of structures. The morphology and synaptology of cobalt labelled and immunostained profiles in our sections were very similar to those reported in previous studies using different double labelling techniques. These results indicate that this new combined method could be used as an alternative double labelling technique in electron microscopic studies on nervous tissues.

Animals↗
PubMed1994

Tissue-specific expression of an oat 12S seed globulin gene in developing tobacco seeds: differential mRNA and protein accumulation.

We studied the expression of the oat globulin gene asglo5 in developing transgenic tobacco seeds. The asglo5 gene promoter directed transcription in the endosperm as well as in the provascular tissue, the presumptive root tip and the shoot apical meristem of the embryo as revealed by GUS reporter gene constructs and in situ hybridization. However, immunological tissue printing detected the oat protein exclusively in the tobacco endosperm, suggesting that extensive post-transcriptional regulatory processes influence the expression of the monocot transgene in the dicot host.

Allergens↗
PubMed1994

Amanita poisoning during the second trimester of pregnancy. A case report and a review of the literature.

Amanita phalloides-type mushroom poisoning is well recognized as causing acute liver injury and often death. Less is known, however, of whether maternal Amanita poisoning is associated with fetal damage or not. In August 1991 four members of a family were hospitalized with food intoxication caused by Amanita phalloides and Amanita verna. One of them died from hepatic and renal failure. The survivors included a 26-year-old woman in the 23rd week of pregnancy. Her clinical symptoms and blood chemistry data (lowest prothrombin activity 23%) indicated intoxication of medium severity. The management consisted of i.v. hydration, forced diuresis, and administration of silibinin, high-dose penicillin, thioctic acid, hydrocortisone, vitamin K, and fresh frozen plasma. Sonographic and obstetric controls failed to show any fetal abnormalities in the acute phase of poisoning. In the 38th week of pregnancy she gave birth to a healthy baby, who has subsequently undergone an undisturbed development. This observation indicated that severe fetal damage did not occur in maternal Amanita poisoning in the second trimester of pregnancy. Thus, at least from the second trimester on, maternal Amanita poisoning is not necessarily an indication for induced abortion.

Adolescent↗
PubMed1994

Comparative study of antibodies that are associated with disease progression in HIV disease.

Two types of antibodies which previously were found to be inversely associated with CD4+ cell counts and which may contribute to the progression of HIV disease were measured in parallel in 55 serum samples of 7 longitudinally tested HIV-infected patients (4 homosexual men, 3 haemophilic men) and in 15 serum samples from 15 patients with advanced AIDS. HIV-infection enhancing antibodies were determined in the presence of near-physiologic human complement concentration using a complement receptor type 2 (CR2) carrying HIV-target cell line. IgG and IgA class autoantibodies directed against human IgG-Fab fragments were measured in specific ELISA assays. In agreement with our previous studies obtained in HIV-seropositive haemophilic patients, significant negative correlations were found between CD4+ cell counts and IgG anti-Fab and IgA anti-Fab antibodies (Spearman correlation coefficient r = -0.587, P < 0.0001; and r = -0.269, P = 0.024, respectively). A significant positive correlation was observed between complement-dependent enhancing antibodies and IgA anti-Fab antibodies (r = 0.408, P = 0.003), whereas the correlation with IgG anti-Fab antibodies was only weak (r = 0.288, P = 0.034). Serum samples with high titres of complement-dependent enhancing antibodies had almost 3 times higher IgA anti-Fab autoantibody activity than sera with low titres (P = 0.0038). Our findings indicate that the two disease markers in HIV disease, enhancing antibodies and autoantibodies directed against the Fab moiety of IgG, are not identical. However, anti-Fab antibodies may contribute to complement-dependent HIV infection enhancement.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Red cell sodium-lithium countertransport and blood pressure in children with insulin-dependent diabetes mellitus.

Sodium-lithium countertransport and blood pressure responses, maximal elevated plasma norepinephrine concentrations induced by acute physical work load and the carbohydrate metabolic state were analyzed in 40 children suffering from insulin-dependent diabetes mellitus (IDDM). Patients were selected according to the duration of the disease to get a horizontal insight into the progression of the diabetes. Sixteen healthy children served as controls. Sodium-lithium countertransport (Na-Li CT) was 281 +/- 64 mumol/l red blood cells (RBC) per hour in the control group. Na-Li CT was elevated in all diabetic groups (newly diagnosed: 455 +/- 48; diabetics for 5-7 years: 495 +/- 48; diabetics for 10-13 years: 470 +/- 36). Plasma norepinephrine concentration increased during physical exercise, the elevation was more pronounced in diabetic children being 13.5 +/- 10.4, 10.1 +/- 5.0 and 12.3 +/- 5.4 nmol/l in the three diabetic groups, respectively, which differed significantly from that of controls (7.94 +/- 2.9; P < 0.01). Systolic blood pressure increased significantly during physical exercise in each group. However, maximal elevated systolic blood pressure was higher in children who had diabetes for more than 10 years than in controls (158 +/- 11 vs. 137 +/- 9.7 mmHg; P < 0.001). Na-Li CT correlated positively with the maximal systolic blood pressure measured during physical exercise in those diabetic children who suffered from diabetes for more than 5 years. High activity of Na-Li CT in combination with elevated blood pressure and high plasma concentration of norepinephrine induced by acute physical exercise may represent a risk of renal/vascular complications in patients suffering from IDDM.

Adolescent↗
PubMed1994

Neutralizing and enhancing antibodies measured in complement-restored serum samples from HIV-1-infected individuals correlate with immunosuppression and disease.

OBJECTIVE: To study the association between the progression of HIV disease and HIV neutralization and enhancement measured in the presence of human complement. DESIGN: Two studies were performed: (1) longitudinal measurement of the complement-dependent enhancing antibodies in parallel with T-cell subset determination in 55 serum samples from seven HIV-infected patients, and (2) determination of the titres of neutralizing and enhancing antibodies in stored samples of 21 HIV-asymptomatic patients obtained between 1986 and 1987 and follow-up of the patients until October 1992. METHODS: HIV-1 [human T-lymphotropic virus (HTLV)IIIB strain, 100 median tissue culture infective dose (TCID50)] was incubated with twofold dilutions of sera in the presence of human complement (final dilution, 1:4) and added to MT-4 cells. HIV growth was monitored daily for 5 days using the reclustering inhibition and p24 immunofluorescence assays. RESULTS: A significant negative correlation between the titres of enhancing antibodies and CD4+ cell count was found in longitudinal measurements. In the prospective studies, marked differences were observed between patients with undetectable, low, or high titres of enhancing antibodies in the clinical course of HIV disease: CD4+ cell counts and percentages decreased more rapidly in the high titre group within 3 years. After 5 years, AIDS developed in five out of six patients in the high titre group but only in five out of 15 of the low titre group (P < 0.05). A similar difference was observed between patients with and without neutralizing antibodies. CONCLUSIONS: Measurement of HIV neutralization and enhancement in complement-containing serum samples using a complement receptor carrying target may provide data of clinical relevance. Neutralization appears to be associated with a favourable prognosis whereas high titre enhancing antibodies predict rapid progression of HIV disease.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Loss of preconditioning in rabbits with vascular tolerance to nitroglycerin.

A preceding right ventricular overdrive pacing (VOP) of 500 b.p.m. for 5 min, markedly reduced the severity of global myocardial ischaemia produced by a subsequent 5-min VOP in conscious rabbits. This VOP-induced preconditioning developed in parallel with an increase in cardiac cyclic guanosine 3':5'-monophosphate (cyclic GMP) content. VOP-induced preconditioning was abolished when the animals had been made tolerant to the vasodilator effect of nitroglycerin (NG). In the heart of the NG-tolerant rabbits, neither VOP nor preconditioning increased cyclic GMP content. This suggests that changes by NG tolerance of cyclic GMP metabolism may account for the loss of VOP-induced preconditioning.

Animals↗