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1.
Commun Agric Appl Biol Sci ; 80(2): 149-52, 2015.
Article de Anglais | MEDLINE | ID: mdl-27145579

RÉSUMÉ

The increasing pressure of oilseed rape pests emphasized the need to improve the insecticide portfolio, i.e. register new active ingredients with new insecticide mode of action. The tested seed treatment formulation applied at 32; 40 and 50 UAT rate of containing cyantraniliprole as active substance. 40 UAT rate gives acceptable control of the Cabbage root fly in each trial. Despite the long lasting flight and egg laying period of cabbage root fly, the standard control products and also this product give 50-65% efficacy. It is enough to reduce damage of the Cabbage root fly and prevent economical damage in oilseed rape.


Sujet(s)
Brassica napus , Diptera , Lutte contre les insectes , Insecticides , Pyrazoles , ortho-Aminobenzoates , Animaux , Brassica napus/croissance et développement , Coléoptères/croissance et développement , Diptera/croissance et développement , Larve , Pupe , Saisons , Graines
2.
Acta Physiol Hung ; 98(4): 480-90, 2011 Dec.
Article de Anglais | MEDLINE | ID: mdl-22173030

RÉSUMÉ

The goal was to develop a rat model for determination of the effects of intrathecally administered drugs on the peripherally induced pruritic behaviors. After chronic intrathecal catheterization, a serotonin derivative (5-methoxytryptamine: MeOT, 200 µg on both sides) was injected into the lower leg skin. After the first period (phase 0: 0-30 min) MeOT injection was repeated and opioid antagonist naltrexone (10 µg), NMDA receptor antagonists ketamine (10-100 µg), kynurenic acid (1-10 µg) or their combinations were injected intrathecally. The second observational period lasted for 60 min (phases I and II, 30-60 and 60-90 min, respectively). MeOT produced pruritic behavior with high degree of interindividual differences. The second MeOT injection caused an enhanced pruritic behavior in Phase I. Naltrexone decreased the pruritic activity, while neither doses of ketamine influenced the effects of MeOT. The higher doses of kynurenic acid resulted in notable decreases in the pruritic behavior. The combinations of naltrexone with ketamine or kynurenic acid produced a prolonged antipruritic effect. Our data suggest an important direction for the development of a new itch model in rats that focuses on the spinal mechanism of itching. Besides, the results revealed the role of the spinal opioid and NMDA receptors in this process.


Sujet(s)
5-Méthoxy-tryptamine/toxicité , Modèles animaux de maladie humaine , Prurit/induit chimiquement , Prurit/physiopathologie , Rat Wistar , Analgésiques/pharmacologie , Animaux , Comportement animal/effets des médicaments et des substances chimiques , Interactions médicamenteuses , Antagonistes des acides aminés excitateurs/pharmacologie , Injections rachidiennes , Kétamine/pharmacologie , Acide kynurénique/pharmacologie , Mâle , Naltrexone/pharmacologie , Antagonistes narcotiques/pharmacologie , Rats , Moelle spinale/effets des médicaments et des substances chimiques , Moelle spinale/physiopathologie
3.
Commun Agric Appl Biol Sci ; 75(1): 209-31, 2010.
Article de Anglais | MEDLINE | ID: mdl-20491414

RÉSUMÉ

The main objectives of European Thematic Network entitled 'Education and Research in Agricultural for Biosystems Engineering in Europe (ERABEE-TN)' is to initiate and contribute to the structural development and the assurance of the quality assessment of the emerging discipline of Biosystems Engineering in Europe. ERABEE is co-financed by the European Community in the framework of the LLP Programme. The partnership consists of 35 participants from 27 Erasmus countries, out of which 33 are Higher Education Area Institutions (EDU) and 2 are Student Associations (ASS). 13 Erasmus participants (e.g. Thematic Networks, Professional Associations, and Institutions from Brazil, Croatia, Russia and Serbia) are also involved in the Thematic Network through synergies. To date, very few Biosystems Engineering programs exist in Europe and those that are initiated are at a very primitive stage of development. The innovative and novel goal of the Thematic Network is to promote this critical transition, which requires major restructuring in Europe, exploiting along this direction the outcomes accomplished by its predecessor; the USAEE-TN (University Studies in Agricultural Engineering in Europe). It also aims at enhancing the compatibility among the new programmes of Biosystems Engineering, aiding their recognition and accreditation at European and International level and facilitating greater mobility of skilled personnel, researchers and students. One of the technical objectives of ERABEE is dealing with mapping and promoting the third cycle studies (including European PhDs) and supporting the integration of research at the 1st and 2nd cycle regarding European Biosystems Engineering university studies. During the winter 2008 - spring 2009 period, members of ERABEE conducted a survey on the contemporary status of doctoral studies in Europe, and on a possible scheme for promotion of cooperation and synergies in the framework of the third cycle of studies and the European Doctorate in Biosystems Engineering in Europe. This paper presents the results of the survey. The legal regulations and their extent on the different countries concerning the third cycle are presented, along with the current structure of third cycle studies. The evolution and adaptation to the new EHEA in each country is also considered. Information was also gathered on the emerging topics of the Biosystems Engineering field and how these topics could be addressed by the new doctoral programmes at the European level.


Sujet(s)
Agriculture/enseignement et éducation , Bioingénierie/enseignement et éducation , Programme d'études , Universités/organisation et administration , Europe
4.
Cent Eur J Public Health ; 11(1): 44-9, 2003 Mar.
Article de Anglais | MEDLINE | ID: mdl-12690803

RÉSUMÉ

In the framework of the Central European Study on Air pollution and Respiratory Health (CESAR), a risk perception and risk communication study was carried out in a total of 25 areas in Bulgaria, the Czech Republic, Hungary, Poland, Romania and the Slovak Republic. This paper is focused on the differences of perception between the Czech (CR) and the Slovak Republic (SR), and the other involved countries. The analysis is based on the data of a structured risk perception questionnaire survey of a random population sample. 6,043 completed questionnaires were collected from the total number of 14,400 distributed ones in 25 areas of the 6 countries. The risk perception was different in the CR and the SR, mainly concerning local environment and health of children in the CR and drug abuse including alcohol consumption and AIDS in the SR. In both countries environmental and health problems were seen as important, but the perceived responsibility for finding a solution was placed with different kinds of institutions.


Sujet(s)
Attitude envers la santé/ethnologie , Pollution de l'environnement/statistiques et données numériques , Opinion publique , Appréciation des risques , Adulte , Pollution de l'air/statistiques et données numériques , Communication , Europe de l'Est/épidémiologie , Priorités en santé , Humains , Enquêtes et questionnaires
5.
Nature ; 419(6903): 131-2, 2002 Sep 12.
Article de Anglais | MEDLINE | ID: mdl-12226653

RÉSUMÉ

The Mexican wave, or La Ola, which rose to fame during the 1986 World Cup in Mexico, surges through the rows of spectators in a stadium as those in one section leap to their feet with their arms up, and then sit down again as the next section rises to repeat the motion. To interpret and quantify this collective human behaviour, we have used a variant of models that were originally developed to describe excitable media such as cardiac tissue. Modelling the reaction of the crowd to attempts to trigger the wave reveals how this phenomenon is stimulated, and may prove useful in controlling events that involve groups of excited people.


Sujet(s)
Modèles biologiques , Activité motrice/physiologie , Loisir , Comportement social , Simulation numérique , Humains , Mexique , Probabilité , Contrôle social informel , Sports , Enregistrement sur magnétoscope
6.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(2 Pt 2): 026704, 2001 Aug.
Article de Anglais | MEDLINE | ID: mdl-11497741

RÉSUMÉ

Many natural and social systems develop complex networks that are usually modeled as random graphs. The eigenvalue spectrum of these graphs provides information about their structural properties. While the semicircle law is known to describe the spectral densities of uncorrelated random graphs, much less is known about the spectra of real-world graphs, describing such complex systems as the Internet, metabolic pathways, networks of power stations, scientific collaborations, or movie actors, which are inherently correlated and usually very sparse. An important limitation in addressing the spectra of these systems is that the numerical determination of the spectra for systems with more than a few thousand nodes is prohibitively time and memory consuming. Making use of recent advances in algorithms for spectral characterization, here we develop methods to determine the eigenvalues of networks comparable in size to real systems, obtaining several surprising results on the spectra of adjacency matrices corresponding to models of real-world graphs. We find that when the number of links grows as the number of nodes, the spectral density of uncorrelated random matrices does not converge to the semicircle law. Furthermore, the spectra of real-world graphs have specific features, depending on the details of the corresponding models. In particular, scale-free graphs develop a trianglelike spectral density with a power-law tail, while small-world graphs have a complex spectral density consisting of several sharp peaks. These and further results indicate that the spectra of correlated graphs represent a practical tool for graph classification and can provide useful insight into the relevant structural properties of real networks.

7.
Nature ; 407(6803): 487-90, 2000 Sep 28.
Article de Anglais | MEDLINE | ID: mdl-11028994

RÉSUMÉ

One of the most disastrous forms of collective human behaviour is the kind of crowd stampede induced by panic, often leading to fatalities as people are crushed or trampled. Sometimes this behaviour is triggered in life-threatening situations such as fires in crowded buildings; at other times, stampedes can arise during the rush for seats or seemingly without cause. Although engineers are finding ways to alleviate the scale of such disasters, their frequency seems to be increasing with the number and size of mass events. But systematic studies of panic behaviour and quantitative theories capable of predicting such crowd dynamics are rare. Here we use a model of pedestrian behaviour to investigate the mechanisms of (and preconditions for) panic and jamming by uncoordinated motion in crowds. Our simulations suggest practical ways to prevent dangerous crowd pressures. Moreover, we find an optimal strategy for escape from a smoke-filled room, involving a mixture of individualistic behaviour and collective 'herding' instinct.


Sujet(s)
Simulation numérique , Surpeuplement , Panique , Urgences , Réaction de fuite , Humains , Modèles biologiques
8.
Orv Hetil ; 141(52): 2815-20, 2000 Dec 24.
Article de Hongrois | MEDLINE | ID: mdl-11202117

RÉSUMÉ

The authors surveyed the prevalence of bronchial asthma in childhood in Budapest in 1995 and in February 1999, via questionnaires directed to paediatricians. In 1995, replies were received from 118 paediatricians in 11 districts, who were responsible for the supervision of 104,087 children, of these, 1.88 +/- 0.87% had been diagnosed as having asthma. In 1999, replies were sent by 153 physicians in 22 of the 23 districts, who had a total of 142,684 children under their care. These included 3228 asthmatics, i.e. a prevalence of 2.26 +/- 0.95%. The difference between the two data was highly significant (p = 0.0001). The prevalence increased by 20% in 4 years. The dust, CO, NO2 and SO2 concentrations in the air were measured constantly at 8 points in Budapest, while ozone level measurements were also made at 2 stations. The counts of pollens and of fungal elements in the air were calculated separately for Buda and for Pest. These data overall revealed that the level of air pollution in Budapest did not deteriorate in the period in question, and the pollen counts from allergizing plants did not rise relative to earlier years. An interesting question (though it is far from certain that this is a causal correlation) can be upposed whether the 13% drop in the number of live births in Hungary during this 4-year period can be connected with the 20% rise in prevalence of childhood asthma.


Sujet(s)
Pollution de l'air/effets indésirables , Allergènes/effets indésirables , Asthme/épidémiologie , Asthme/étiologie , Pollen/effets indésirables , Adolescent , Enfant , Enfant d'âge préscolaire , Femelle , Santé mondiale , Humains , Hongrie/épidémiologie , Mâle , Prévalence
9.
Inorg Chem ; 39(4): 799-805, 2000 Feb 21.
Article de Anglais | MEDLINE | ID: mdl-11272579

RÉSUMÉ

This study consists of two parts: The first part comprised an experimental determination of the kinetic parameters for the exchange of water between UO2(H2O)5(2+) and bulk water, including an ab initio study at the SCF and MP2 levels of the geometry of UO2(H2O)5(2+), UO2(H2O)4(2+), and UO2(H2O)6(2+) and the thermodynamics of their reactions with water. In the second part we made an experimental study of the rate of water exchange in uranyl complexes and investigated how this might depend on inter- and intramolecular hydrogen bond interactions. The experimental studies, made by using 17O NMR, with Tb3+ as a chemical shift reagent, gave the following kinetic parameters at 25 degrees C: kex = (1.30 +/- 0.05) x 10(6) s(-1); deltaH(not equal to) = 26.1 +/- 1.4 kJ/mol; deltaS(not equal to) = -40 +/- 5J J/(K mol). Additional mechanistic indicators were obtained from the known coordination geometry of U(VI) complexes with unidentate ligands and from the theoretical calculations. A survey of the literature shows that there are no known isolated complexes of UO2(2+) with unidentate ligands which have a coordination number larger than 5. This was corroborated by quantum chemical calculations which showed that the energy gains by binding an additional water to UO2(H2O)4(2+) and UO2(H2O)5(2+) are 29.8 and -2.4 kcal/mol, respectively. A comparison of the change in deltaU for the reactions UO2(H2O)5(2+)--> UO2(H2O)4(2+) + H2O and UO2(H2O)5(2+) + H2O --> UO2(H2O)6(2+) indicates that the thermodynamics favors the second (associative) reaction in gas phase at 0 K, while the thermodynamics of water transfer between the first and second coordination spheres, UO2(H2O)5(2+) --> UO2(H2O)4(H2O)2+ and UO2(H2O)5(H2O)2+ --> UO2(H2O)6(2+), favors the first (dissociative) reaction. The energy difference between the associative and dissociative reactions is small, and solvation has to be included in ab initio models in order to allow quantitative comparisons between experimental data and theory. Theoretical calculations of the activation energy were not possible because of the excessive computing time required. On the basis of theoretical and experimental studies, we suggest that the water exchange in UO2(H2O)5(2+) follows a dissociative interchange mechanism. The rates of exchange of water in UO2(oxalate)F(H2O)2- (and UO2(oxalate)F2(H2O)2- studied previously) are much slower than in the aqua ion, kex = 1.6 x 10(4) s(-1), an effect which we assign to hydrogen bonding involving coordinated water and fluoride. The kinetic parameters for the exchange of water in UO2(H2O)52+ and quenching of photo excited *UO2(H2O)5(2+) are very near the same, indicating similar mechanisms.

10.
Acta Chir Hung ; 38(2): 147-9, 1999.
Article de Anglais | MEDLINE | ID: mdl-10596317

RÉSUMÉ

The orthodox method of the treatment of gallstone disease is laparoscopic cholecystectomy (LC) days or weeks after endoscopic retrograde cholangiopancreatography + endoscopic spincterotomy (ERCP+ES). It can be advantageous from the point of financing, that is double reimbursement (2 x DRG). On the other hand there are some disadvantages of this procedure: longer hospital stay, further suffering of the patient, difficulties at operation because of inflammation provoked by ERCP (11% 14/120 in 3 month). We report on our experience with the treatment of common bile duct stones within 24 h by sequential endoscopic-laparoscopic management. The gallstone disease of a 32 year old woman was diagnosed by ultrasonography and laboratory tests. She had ERCP+ES in the morning and LC 7 hours later. There was no complication and the patient was discharged already on the 3rd day.


Sujet(s)
Cholangiopancréatographie rétrograde endoscopique , Cholécystectomie laparoscopique , Calculs biliaires/chirurgie , Sphinctérotomie endoscopique , Adulte , Femelle , Calculs biliaires/diagnostic , Calculs biliaires/imagerie diagnostique , Humains , Durée du séjour , Facteurs temps , Échographie
11.
Neuroreport ; 10(14): 3021-5, 1999 Sep 29.
Article de Anglais | MEDLINE | ID: mdl-10549816

RÉSUMÉ

We recently reported that not only lymphoid cells, but cells of neuronal origin may harbor C5a receptors (C5aR) as suggested by results of RT-PCR testing and that an apoptotic pathway is associated with the C5aR. To determine whether C5aR is expressed as an integral membrane protein, we generated mono- and polyclonal anti-C5aR antibodies. Flow cytometry showed a low-level expression of C5aR in TGW neuroblastoma cells. Epitope mapping suggested that a conformation change in C5aR occurs when exposed to C5a. Although an aphysiologically high concentration of C5a is necessary for inducing a transient increase in the intracellular Ca2+ level, TGW cells do employ the signal transduction pathway associated with C5aR, suggesting that these cells may serve as putative model for C5aR-expressing neurons.


Sujet(s)
Antigènes CD/biosynthèse , Tumeurs du cerveau/métabolisme , Complément C5a/métabolisme , Neuroblastome/métabolisme , Récepteurs au complément/biosynthèse , Calcium/métabolisme , Cytométrie en flux , Humains , Immunoglobuline M/biosynthèse , Immunoglobuline M/génétique , Hybridation in situ , ARN messager/biosynthèse , Récepteur à l'anaphylatoxine C5a , Cellules cancéreuses en culture , Facteur de nécrose tumorale alpha/pharmacologie
12.
Neuroscience ; 86(3): 903-11, 1998 Oct.
Article de Anglais | MEDLINE | ID: mdl-9692726

RÉSUMÉ

Human neuroblastoma TGW cells express a C5a anaphylatoxin receptor-like molecule termed neuronal C5a receptor. A C5a-receptor fragment peptide (termed PR226-multiple antigenic peptide) can induce rapid apoptosis in TGW cells via neuronal C5a receptor-associated signal transduction pathways. In order to analyse role of activated complement system in neurodegeneration, TGW cells were exposed to an oligomer form of a C5a fragment (amino acids: 37-53) peptide termed PL37-multiple antigenic peptide. Upon treatment with PL37-multiple antigenic peptide, an increased nuclear c-fos expression was shown within 30 min. DNA fragmentation, a hallmark of apoptosis, was noted within 4 h. Extracellular administration of 100 nM PL37-multiple antigenic peptide evoked inward calcium current pulses. At higher doses (0.5 microM-1 microM), PL37-multiple antigenic peptide evoked higher current pulses, followed by an irreversible, high inward current. To exert its apoptotic effect, PL37-multiple antigenic peptide utilizes a pertussis toxin-sensitive signal transduction pathway associated with the neuronal C5a receptor. Activation of the complement system and therefore release of C5a has already been reported in Alzheimer's disease. In addition, the presence of the Kunitz-type proteinase inhibitors indicates an impaired protease function and a possible abnormal fragmentation of C5a anaphylatoxin. Our data suggest that neurons expressing neuronal C5a receptor are more vulnerable to the apoptosis associated with the neuronal C5a receptor and the possibility that abnormal activation of C5a receptor and C5a anaphylatoxin fragments might be involved in the pathogenesis of Alzheimer's disease.


Sujet(s)
Anaphylatoxines/pharmacologie , Antigènes CD/physiologie , Apoptose/physiologie , Récepteurs au complément/physiologie , Anaphylatoxines/composition chimique , Animaux , Apoptose/effets des médicaments et des substances chimiques , Complément C5a/pharmacologie , Complément C5a/physiologie , Humains , Cinétique , Cellules L (lignée cellulaire) , Potentiels de membrane , Souris , Neuroblastome , Techniques de patch-clamp , Fragments peptidiques/pharmacologie , Protéines proto-oncogènes c-fos/biosynthèse , Récepteur à l'anaphylatoxine C5a , Protéines recombinantes/biosynthèse , Transduction du signal , Transfection , Cellules cancéreuses en culture
13.
J Physiol ; 507 ( Pt 3): 679-87, 1998 Mar 15.
Article de Anglais | MEDLINE | ID: mdl-9508829

RÉSUMÉ

1. We report the first experimental evidence of a neuronal C5a receptor (nC5aR) in human cells of neuronal origin. Expression of nC5aR mRNA was demonstrated by the reverse transcriptase-polymerase chain reaction (RT-PCR) in TGW human neuroblastoma cells. 2. Expression of a functional C5aR was supported by the finding that C5a evoked a transient increase in the intracellular calcium level as measured by flow cytometry (FACS). 3. To analyse the function of the nC5aR, an antisense peptide fragment of the C5aR was used. Previous data showed that a C5aR fragment (a peptide termed PR226) has C5aR agonist and antagonist effects in U-937 cells depending on the concentration of the peptide. We found that a multiple antigenic peptide (MAP) form of the same peptide (termed PR226-MAP) induced rapid elevation of nuclear c-fos immunoreactivity and resulted in DNA fragmentation, a characteristic sign of apoptosis, in TGW cells. 4. Early electrophysiological events characteristic of apoptosis were also detected: intermittent calcium current pulses were recorded within 1-2 min of peptide administration. C5a pretreatment delayed the onset of this calcium influx. 5. We also demonstrated that the apoptotic pathway is linked to nC5aR via pertussis toxin-sensitive G-proteins. 6. Although the function of C5a and its receptor on neurons is unknown, these results suggest that an abnormal activation of this signal transduction pathway can result in apoptosis and, subsequently, in neurodegeneration.


Sujet(s)
Antigènes CD/physiologie , Calcium/métabolisme , Complément C5a/pharmacologie , Neurones/physiologie , Récepteurs au complément/physiologie , Animaux , Antigènes CD/biosynthèse , Apoptose/effets des médicaments et des substances chimiques , Noyau de la cellule/métabolisme , Fragmentation de l'ADN , Protéines G/métabolisme , Humains , Cinétique , Cellules L (lignée cellulaire) , Potentiels de membrane/effets des médicaments et des substances chimiques , Potentiels de membrane/physiologie , Souris , Neuroblastome , Neurones/cytologie , Oligonucléotides antisens/pharmacologie , Techniques de patch-clamp , Fragments peptidiques/pharmacologie , Peptides/pharmacologie , Toxine pertussique , Réaction de polymérisation en chaîne , Protéines proto-oncogènes c-fos/biosynthèse , ARN messager/biosynthèse , Récepteur à l'anaphylatoxine C5a , Récepteurs au complément/biosynthèse , Protéines recombinantes/biosynthèse , Transduction du signal/effets des médicaments et des substances chimiques , Transcription génétique , Cellules cancéreuses en culture , Facteurs de virulence des Bordetella/pharmacologie
14.
Clin Endocrinol (Oxf) ; 47(1): 87-92, 1997 Jul.
Article de Anglais | MEDLINE | ID: mdl-9302377

RÉSUMÉ

OBJECTIVE: To investigate the effect of varying amounts of iodine intake on the prevalence of thyroid dysfunction, autoimmunity and goitre in old age. DESIGN: The first screening study where elderly subjects with varying amounts of iodine supply but from the same geographical and ethnographical region (Carpathian basin) were compared, and all hormone measurements and ultrasonography were performed by the same laboratory or person. PATIENTS: Nursing home residents were screened for thyroid disorders from: (A) an iodine-deficient area, Northern Hungary (n = 119; median age 81 years; median iodine excretion (MIE) 0.065 mumol/mmol creatinine (equivalent to 72 micrograms/g creatinine); (B) an area of obligatory iodinated salt prophylaxis since the 1950s, Slovakia (n = 135; median age 81 years, MIE 0.090 mumol/mmol creatinine (equivalent to 100 micrograms/g creatinine)) and (C) an abundant iodine intake area, Eastern Hungary (n = 92; median age 78 years; MIE 0.462 mumol/mmol creatinine (equivalent to 513 micrograms/g creatinine)). MEASUREMENTS: TSH, T4, free T4, T3, thyroglobulin (Tg), antibodies to Tg (AbTg) and to thyroid peroxidase (AbTPO), iodine excretion, ultrasonography of the thyroid gland. RESULTS: In regions A, B, and C, the prevalence of unsuspected clinical hypothyroidism was 0.8%, 1.5% and 7.6% (P = 0.006), with all cases except one being antibody positive (Ab+). The occurrence of subclinical hypothyroidism was 4.2% in region A, 10.4% in region B and 23.9% in region C (P < 0.001), but only 3 of 22 cases with subclinical hypothyroidism from region C were Ab+. The overall prevalence of Ab positivity (either antiTg+ or antiTPO+) was similar in the three regions (A, 19.3%; B, 24.4%; C, 22.8%). The occurrence of hyperthyroidism (clinical plus subclinical) was 3.4% in region A, 3.0% in region B and 0% in region C (not significant). The rate of elevated Tg levels was similar in the three regions. The prevalence of goitre was 39.4%, 16.4% and 12.2% (P < 0.001), respectively in regions A, B and C. In euthyroid subjects the mean ultrasonographically determined thyroid volume was 21.9 ml in region A, 13.6 ml in region B and 15.1 ml in region C (ANOVA F = 5.76; P = 0.0038). There was no significant difference in the occurrence of cases with hypoechogenic echotexture of the thyroid gland. CONCLUSIONS: The screening for hypothyroidism in nursing home residents living in iodine-rich regions is justified by the high prevalence of unsuspected clinical hypothyroidism. The high prevalence of antibody positivity in old age is independent of the iodine supply, but iodine supply has a determining role in the development of autoimmune hypothyroidism in the aged. Most cases of subclinical hypothyroidism in iodine-rich regions are not of autoimmune origin. In old age, hypoechogenic texture of the thyroid gland is not predictive of thyroid dysfunction.


Sujet(s)
Maladies auto-immunes/épidémiologie , Goitre/épidémiologie , Iode/déficit , Maladies de la thyroïde/épidémiologie , Sujet âgé , Sujet âgé de 80 ans ou plus , Maladies auto-immunes/imagerie diagnostique , Maladies auto-immunes/métabolisme , Études transversales , Femelle , Goitre/métabolisme , Humains , Hongrie/épidémiologie , Hypothyroïdie/imagerie diagnostique , Hypothyroïdie/étiologie , Hypothyroïdie/métabolisme , Iode/administration et posologie , Mâle , Adulte d'âge moyen , Prévalence , Slovaquie/épidémiologie , Maladies de la thyroïde/imagerie diagnostique , Maladies de la thyroïde/métabolisme , Glande thyroide/imagerie diagnostique , Échographie
15.
Arzneimittelforschung ; 47(4A): 551-5, 1997 Apr.
Article de Anglais | MEDLINE | ID: mdl-9205763

RÉSUMÉ

Two hundred and fifty patients were included in a double-blind, parallel, randomized, controlled clinical trial. Duodenal ulcer treatment lasted up to 8 weeks. Forty-nine patients were followed up for prevention of ulcer relapse for up to one year. All patients received either ranitidine (300 mg/day in the healing phase and 150 mg/day in the follow-up phase) or ebrotidine (N-[(E)-[[2-[[[2-[(diaminomethylene)amino]-4 -thiazolyl]methyl]thio]ethyl]amino]methylene]-4-bromo-benzenesulfonamide , CAS 100981-43-9, FI-3542) (400 mg/day in both phases) as a single dose at bedtime. Both groups were matched in all demographic parameters, except for a significantly higher percentage of smokers in the ranitidine group. The percentage of total healing was almost the same with both products. Healing occurred in a higher percentage with ebrotidine at weeks 4 (75% versus 66.7%) and 6 (87% versus 79.7%). A higher effect of ebrotidine on the incidence of duodenitis was identified during the whole study, but only reached statistical significance at week 6. The relapse rate during the follow-up phase showed no differences between the two study treatments, relapse percentage figures being 25% for ebrotidine and 24% for ranitidine. There were no differences in the number of unscheduled visits between the two groups, although 57% of patients in the ranitidine group had to make a second follow-up visit, as compared with 33% in the ebrotidine group. Both drugs caused hardly any side effects, affecting only one patient from each group: one patient with ebrotidine suffered from diarrhoea and one patient with ranitidine developed a skin rash on the limbs. Administration of ebrotidine in a single dose (400 mg/d) was at least as effective and safe as ranitidine both for healing and relapse prevention in patients with duodenal ulcer.


Sujet(s)
Benzènesulfonates/usage thérapeutique , Antihistaminiques des récepteurs H2/usage thérapeutique , Ranitidine/usage thérapeutique , Thiazoles/usage thérapeutique , Adulte , Méthode en double aveugle , Femelle , Études de suivi , Humains , Mâle , Adulte d'âge moyen , Récidive , Fumer
16.
Mol Cell Biol ; 16(8): 4357-65, 1996 Aug.
Article de Anglais | MEDLINE | ID: mdl-8754836

RÉSUMÉ

In Saccharomyces cerevisiae, nutrient levels control multiple cellular processes. Cells lacking the SNF1 gene cannot express glucose-repressible genes and do not accumulate the storage polysaccharide glycogen. The impaired glycogen synthesis is due to maintenance of glycogen synthase in a hyperphosphorylated, inactive state. In a screen for second site suppressors of the glycogen storage defect of snf1 cells, we identified a mutant gene that restored glycogen accumulation and which was allelic with PHO85, which encodes a member of the cyclin-dependent kinase family. In cells with disrupted PHO85 genes, we observed hyperaccumulation of glycogen, activation of glycogen synthase, and impaired glycogen synthase kinase activity. In snf1 cells, glycogen synthase kinase activity was elevated. Partial purification of glycogen synthase kinase activity from yeast extracts resulted in the separation of two fractions by phenyl-Sepharose chromatography, both of which phosphorylated and inactivated glycogen synthase. The activity of one of these, GPK2, was inhibited by olomoucine, which potently inhibits cyclin-dependent protein kinases, and contained an approximately 36-kDa species that reacted with antibodies to Pho85p. Analysis of Ser-to-Ala mutations at the three potential Gsy2p phosphorylation sites in pho85 cells implicated Ser-654 and/or Thr-667 in PHO85 control of glycogen synthase. We propose that Pho85p is a physiological glycogen synthase kinase, possibly acting downstream of Snf1p.


Sujet(s)
Calcium-Calmodulin-Dependent Protein Kinases/métabolisme , Kinases cyclines-dépendantes/métabolisme , Glycogène/métabolisme , Protein-Serine-Threonine Kinases/métabolisme , Protéines de Saccharomyces cerevisiae , Saccharomyces cerevisiae/métabolisme , Allèles , Séquence d'acides aminés , Séquence nucléotidique , Amorces ADN/composition chimique , Protéines fongiques/métabolisme , Glucose/métabolisme , Glycogen Synthase Kinases , Données de séquences moléculaires , Mutagenèse par insertion , Cartographie peptidique , Phosphates/métabolisme , Phosphoprotein Phosphatases/métabolisme
17.
Mol Cell Biol ; 15(12): 6632-40, 1995 Dec.
Article de Anglais | MEDLINE | ID: mdl-8524228

RÉSUMÉ

Glycogen, a branched polymer of glucose, is a storage molecule whose accumulation is under rigorous nutritional control in many cells. We report the identification of two Saccharomyces cerevisiae genes, GLG1 and GLG2, whose products are implicated in the biogenesis of glycogen. These genes encode self-glucosylating proteins that in vitro can act as primers for the elongation reaction catalyzed by glycogen synthase. Over a region of 258 residues, the Glg proteins have 55% sequence identify to each other and approximately 33% identity to glycogenin, a mammalian protein postulated to have a role in the initiation of glycogen biosynthesis. Yeast cells defective in either GLG1 or GLG2 are similar to the wild type in their ability to accumulate glycogen. Disruption of both genes results in the inability of the cells to synthesize glycogen despite normal levels of glycogen synthase. These results suggest that a self-glucosylating protein is required for glycogen biosynthesis in a eukaryotic cell. The activation state of glycogen synthase in glg1 glg2 cells is suppressed, suggesting that the Glg proteins may additionally influence the phosphorylation state of glycogen synthase.


Sujet(s)
Glucosyltransferases/génétique , Glucosyltransferases/métabolisme , Glycogène/biosynthèse , Protéines de Saccharomyces cerevisiae , Saccharomyces cerevisiae/métabolisme , 1,4-alpha-Glucan branching enzyme/génétique , 1,4-alpha-Glucan branching enzyme/métabolisme , Séquence d'acides aminés , Séquence nucléotidique , Clonage moléculaire , Amorces ADN , Gènes fongiques , Génotype , Glycogen synthase/métabolisme , Cinétique , Données de séquences moléculaires , Protéines recombinantes/métabolisme , Saccharomyces cerevisiae/génétique , Similitude de séquences d'acides aminés , Sites étiquetés par des séquences
18.
Int J Biochem Cell Biol ; 27(8): 767-73, 1995 Aug.
Article de Anglais | MEDLINE | ID: mdl-7584610

RÉSUMÉ

Serine/threonine protein phosphatases are also involved in the control of cell division. The aim of the present study was to compare the activity of protein phosphatase 1 (PP1) and 2A (PP2A) in cell extracts of the budding and fission yeast, made at different phases of growth. The activities of PP1 and PP2A toward phosphorylase were similar in extracts of S. cerevisiae. In S. pombe extracts, PP1 was responsible for more than 80% of the phosphorylase phosphatase activity. Ammonium sulfate-ethanol treatment increased the specific activity of the phosphatases and the percentage of PP2A in S. cerevisiae extracts. No increase in the proportion of PP2A was observed upon the same treatment of S. pombe extracts. The above results were confirmed by fractionation of PP1 and PP2A activities on a heparin-Sepharose column. The proportion of PP1 and PP2A activities did not change significantly during exponential cell growth but cells from stationary phase exhibited lower phosphatase activities. These results may indicate a lower level of expression of the PP2A genes in S. pombe and/or differences in the structure of the holoenzymes or their regulators in the two genera.


Sujet(s)
Isoenzymes/analyse , Phosphoprotein Phosphatases/analyse , Saccharomyces cerevisiae/enzymologie , Schizosaccharomyces/enzymologie , Division cellulaire/physiologie , Protein Phosphatase 1 , Saccharomyces cerevisiae/croissance et développement , Schizosaccharomyces/croissance et développement , Spécificité d'espèce , Spécificité du substrat
19.
Cell Mol Neurobiol ; 14(6): 809-17, 1994 Dec.
Article de Anglais | MEDLINE | ID: mdl-7641238

RÉSUMÉ

1. The effects of aluminium (Al) on calcium (Ca) currents were investigated by using the conventional two-electrode voltage clamp technique in Helix pomatia neurons. The peak amplitude, kinetics, and voltage dependence of activation and inactivation of the Ca currents were studied in the presence of 10(-5)-10(-3) M AlCl3, at pH 6. 2. Al prolonged the rising phase of the Ca currents and therefore increased the time to peak at each command voltage step used. 3. There was no significant influence of Al on the peak amplitude of the Ca currents, but the voltage dependence of the time to peak, activation, and inactivation of the Ca currents shifted to more positive potentials as a consequence of Al treatment. 4. The leak currents were not influenced by Al up to 1 mM, which was the maximal dose applied. 5. The results support the suggestion that Al may modify the Ca homeostasis and that it exerts a neurotoxic effect, at least in part, by modulation of the Ca current of the neuronal membrane.


Sujet(s)
Aluminium/pharmacologie , Canaux calciques/physiologie , Neurones/physiologie , Aluminium/toxicité , Animaux , Calcium/métabolisme , Canaux calciques/effets des médicaments et des substances chimiques , Membrane cellulaire/effets des médicaments et des substances chimiques , Membrane cellulaire/physiologie , Relation dose-effet des médicaments , Ganglions des invertébrés/physiologie , , Homéostasie , Concentration en ions d'hydrogène , Techniques in vitro , Cinétique , Potentiels de membrane/effets des médicaments et des substances chimiques , Potentiels de membrane/physiologie , Neurones/effets des médicaments et des substances chimiques , Facteurs temps
20.
Carbohydr Res ; 254: 91-104, 1994 Feb 17.
Article de Anglais | MEDLINE | ID: mdl-8180999

RÉSUMÉ

Acetylated 1-cyanoglycals (2,6-anhydro-3-deoxyhept/hex-2-enononitriles) were prepared by direct elimination of acetic acid from the appropriate acetylated 2,6-anhydrohept/hexononitriles with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in aprotic solvents. Heterocyclisation of the cyano group of acetylated 1-cyano-D-galactal with 2-aminothiophenol led to 2-(3,4,6-tri-O-acetyl-2-deoxy-D-lyxo-hex-1-enopyranosyl)benz othiazole. Several 2-(per-O-acetylhexo/pentopyranosyl)benzothiazoles also gave 2-(per-O-acetyl-2-deoxyhex/pent-1-enopyranosyl)benzothiazole s with DBU. 3-(Per-O-acetylhexo/pentopyranosyl)-[1,2,4]triazolo[4,3-a] pyrimidines rearranged with DBU to the corresponding acetylated 2-glycosyl-[1,2,4]triazolo[1,5-a]pyrimidines. By the reaction of 1-cyano-D-galactal with ammonium azide, 2-(3,4,6-tri-O-acetyl-2-deoxy-D-lyxo-hex-1-enopyranosyl)tetr azole was prepared and then transformed with carboxylic acid derivatives into 2-(3,4,6-tri-O-acetyl-2-deoxy-D-lyxo-hex-1-enopyranosyl)-5-s ubstituted-1,3,4- oxadiazoles.


Sujet(s)
Hétérosides/synthèse chimique , Nucléosides/synthèse chimique , Oxadiazoles/synthèse chimique , Thiazoles/synthèse chimique , Triazoles/synthèse chimique , Cyanures , Hétérosides/composition chimique , Indicateurs et réactifs , Spectroscopie par résonance magnétique , Structure moléculaire , Nucléosides/composition chimique , Pouvoir rotatoire , Oxadiazoles/composition chimique , Solvants , Stéréoisomérie , Thiazoles/composition chimique , Triazoles/composition chimique
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