Mechanism of uptake of the catecholic (7)-��-formamido cephalosporin BRL 41897A by klebsiella pneumoniae

The catecholic cephalosporin BRL 41897 A is resistant to ��-lactamases and is taken up by bacteria via the iron transport system. The uptake of this antibiotic in E.coli uses the Fiu and Cir outer membrane proteins, whereas in P. aerugtnosa it enters via the pyochelin transport system. In this thesis mutants of K. pneumoniae resistant to BRL 41897A were isolated using TnphoA mutagenesis and used to study the mechanism of uptake of BRL 41897A by K. pneumoniae. The activity of BRL 41897A towards the parent strain (M10) was increased in iron depleted media, whereas no significant differences in the resistant (KSL) mutants were observed. Three mutants (KSL19, KSL38and KSL59) produced decreased amounts of certain iron-regulated outer membrane proteins. The uptake of 55Fe-BRL 41897A by M10 in iron-deficient medium was higher than in iron-rich medium. This result indicated the involvement of an iron transport system in the uptake of BRL 41897A by K. pneumoniae. Uptake by the KSL mutants in iron-deficient culture was higher than that by M10. This result, supported by analysis of outer membrane and periplasmic proteins of the KSL mutants, indicates that loss of one outer membrane protein can be compensated by over expression of other outer membrane and/or periplasmic proteins. However, the increased uptake of BRL 41897A by the KSL mutants did not reflect increased activity towards these strains, indicating that there are defects in the transport of BRL 41897A resulting in failure to reach the penicillin binding protein target sites in the cytoplasmic membrane. Southern blotting of chromosomal digests and sequencing in one mutant (KSL19) showed that only one copy of TnphoA was inserted into its chromosome. A putative TnphoA inserted gene in KSL19, designated kslA, carrying a signal sequence was identified. Transformation of a fragment containing the kslA gene into KSL19 cells restored the sensitivity to BRL 41897A to that of the parent strain. Data base peptide sequence searches revealed that the kslA gene in the KSL19 has some amino acid homology with the E. coli ExbD protein, which is involved in stabilisation of the TonB protein.��

Gastos do Sistema ��nico de Sa��de com interna����es por causas externas em S��o Jos�� dos Campos, S��o Paulo, Brasil

O objetivo do estudo foi mensurar os gastos diretos do Sistema ��nico de Sa��de (SUS) com interna����es por causas externas em S��o Jos�� dos Campos, S��o Paulo, Brasil. Foram estudadas as interna����es por les��es decorrentes de causas externas, respectivamente cap��tulos XIX e XX da CID-10, no primeiro semestre de 2003, no Hospital Municipal Dr. Jos�� de Carvalho Florence. Foram analisados os valores pagos atrav��s do SUS, ap��s a verifica����o da qualidade dos dados nos prontu��rios de 976 interna����es. Os maiores gastos totais foram por interna����es decorrentes de acidentes de transporte e quedas. O maior gasto m��dio de interna����o foi por acidentes de transporte (R$ 614,63), seguido das agress��es (R$ 594,90). As les��es que representaram maior gasto m��dio foram as fraturas de pesco��o (R$ 1.191,42) e traumatismo intracraniano (R$ 1.000,44). As interna����es com maior custo-dia foram fraturas do cr��nio e dos ossos da face (R$ 166,72) e traumatismo intra-abdominal (R$ 148,26). Os resultados encontrados demonstraram que os acidentes de transporte, as quedas e as agress��es s��o importantes fontes de gastos com interna����es por causas externas no munic��pio.

Validity of (-)-[H-3]-CGP 12177A as a radioligand for the 'putative beta(4)-adrenoceptor' in rat atrium

1 We have recently suggested the existence in the heart of a 'putative beta(4)-adrenoceptor' based on the cardiostimulant effects of non-conventional partial agonists, compounds that cause cardiostimulant effects at greater concentrations than those required to block beta(1)- and Bz-adrenoceptors. We sought to obtain further evidence by establishing and validating a radioligand binding assay for this receptor with (-)-[H-3]-CGP 12177A ((-)-4-(3-tertiarybutylamino-2-hydroxypropoxy) benzimidazol-2-one) in rat atrium. We investigated (-)-[H-3]-CGP 12177A for this purpose for two reasons, because it is a nonconventional partial agonist and also because it is a hydrophilic radioligand. 2 Increasing concentrations of(-)-[H-3]-CGP 12177A, in the absence or presence of 20 mu M (-)-CGP 12177A to define non-specific binding, resulted in a biphasic saturation isotherm. Low concentrations bound to beta(1)- and beta(2)-adrenoceptors (pK(D) 9.4+/-0.1, B-max 26.9+/-3.1 fmol mg(-1) protein) and higher concentrations bound to the 'putative beta(4)-adrenoceptor' (pK(D) 7.5+/-0.1, B-max 47.7+/-4.9 fmol mg(-1) protein). In other experiments designed to exclude beta(1)- and beta(2)-adrenoceptors, (-)-[H-3]-CGP 12177A (1-200 nM) binding in the presence of 500 nM (-)-propranolol was also saturable (pK(D) 7.6+/-0.1, B-max 50.8+/-7.4 fmol mg(-1) protein). 3 The non-conventional partial agonists (-)-CGP 12177A (pK(i) 7.3+/-0.2), (+/-)-cyanopindolol (pK(i) 7.6+/-0.2), (-)-pindolol (pK(i) 6.6+/-0.1) and (+)-carazolol (pk(i), 7.2+/-0.2) and the antagonist (-)-bupranolol (pK(i) 6.6+/-0.2), all competed for (-)-[H-3]-CGP 12177A binding in the presence of 500 nM (-)-propranolol at the 'putative beta(4)-adrenoceptor', with affinities closely similar to potencies and affinities determined in organ bath studies. 4 The catecholamines competed with (-)-[H-3]-CGP 12177A at the 'putative beta(4)-adrenoceptor' in a stereoselective manner, (-)-noradrenaline (pK(iH) 6.3 +/- 0.3, pK(i), 3.5 +/- 0.1), (-)-adrenaline (pK(iH) 6.5 +/- 0.2, pK(iL) 2.9 +/- 0.1), (-)-isoprenaline (pK(iH) 6.2 +/- 0.5, pK(iL) 3.3 +/- 0.1), (+)-isoprenaline (pK(i) < 1.7), (-)-R0363 ((-)-(1-(3,4-dimethoxyphenethylamino)-3-(3,4-dihydroxyphenoxy)-2-propranol)oxalate, pK(i) 5.5 +/- 0.1). 5 The inclusion of guanosine 5-triphosphate (GTP 0.1 mM) had no effect on binding of (-)-CGP 12177A or (-)-isoprenaline to the 'putative beta(4)-adrenoceptor'. In competition binding studies, (-)-CGP 12177A competed with (-)-[H-3]-CGP 12177A for one receptor state in the absence (pK(i) 7.3 +/- 0.2) or presence of GTP (pK(i) 7.3 +/- 0.2). (-)-Isoprenaline competed with (-)-[H-3]-CGP 12177A for two states in the absence (pK(iH) 6.6 +/- 0.3, pK(iL) 3.5 +/- 0.1; % H 25 +/- 7) or presence of GTP (pK(iH) 6.2 +/- 0.5, pK(iL) 3.4 +/- 0.1; % H 37 +/- 6). In contrast, at beta(1)-adrenoceptors, GTP stabilized the low affinity state of the receptor for (-)-isoprenaline. 6 The specificity of binding to the 'putative beta(4)-adrenoceptor' was tested with compounds active at other receptors. High concentrations of the beta(4)-adrenoceptor agonists, BRL 37344 ((RR + SS)[4-[2-[[2-(3-chlorophenyl)-2-hydroxy -ethyl]amino]propyl]phenoxy]acetic acid, 6 mu M), SR 58611A (ethyl((7S)-7-[(2R)-2-(3-chlorophenyl)-2-hydroxyethylamino]-5,6,7,8-tetrahydronaphtyl-2-yloxy) acetate hydrochloride, 6 mu M), ZD 2079 ((+/-)-1-phenyl-2-(2-4-carboxymethylphenoxy)-ethylamino)ethan-1-ol, 60 mu M), CL 316243 (disodium (R,R)-5-[2-[2-(3-chlorophenyl)-2-hydroxyethyl-amino]propyl]- 1,3-benzodioxole-2,2-dicarboxylate, 60 mu M) and antagonist SR 59230A (3-(2-ethylphenoxy)-1-[(1S)-1,2,3,4-tetrahydronaphth-1-ylamino]-2S-2-propanol oxalate, 6 mu M) caused less than 22% inhibition of (-)-[H-3]-CGP 12177A binding in the presence of 500 nM (-)-propranolol. Histamine (1 mM), atropine (1 mu M), phentolamine (10 mu M), 5-HT(100 mu M) and the 5-HT4 receptor antagonist SE 207710 ((1-butyl-4-piperidinyl)-methyl 8-amino-7-iodo-1 ,4-benzodioxan-5-carboxylate, 10 nM) caused less than 26% inhibition of binding. 7 Non-conventional partial agonists, the antagonist (-)-bupranolol and catecholamines all competed for (-)-[H-3]-CGP 12177A binding in the absence of (-)-propranolol at beta(1)-adrenoceptors, with affinities (pK(i)) ranging from 1.6-3.6 log orders greater than at the 'putative beta(4)-adrenoceptor'. 8 We have established and validated a radioligand binding assay in rat atrium for the 'putative beta(4)-adrenoceptor' which is distinct from beta(1)-, beta(2)- and beta(3)-adrenoceptors. The stereoselective interaction with the catecholamines provides further support for the classification of the receptor as 'putative beta(4)-adrenoceptor'.

Genetic diversity among Toxoplasma gondii isolates of small ruminants from Brazil: Novel genotypes revealed

Recent studies indicated that Toxoplasma gondii isolates of many domestic animal hosts from Brazil are genetically and biologically different from those in USA and Europe. Despite of high pathogenicity of this parasite to small ruminants, the epidemiology and genetic diversity of T. gondii in these animals are not well understood in Brazil. In this study, a total of 28 T. gondii samples (16 isolates from sheep in Sao Paulo state, and 12 isolates from goats in the states of Sao Paulo and Rio Grande do Norte) were genotyped using genetic markers SAG1, SAG2, SAG3, BTUB, CRAG, c22-8, c29-2, L358, PK1, Apico and CS3. Eleven genotypes were identified from these T. gondii isolates. Eight isolates (4 from sheep and 4 from goats) were grouped into the common clonal type Brl lineage. One sheep isolate was grouped to the type BrIII lineage. Five isolates grouped to three previously identified genotypes in Brazil, and 13 isolates grouped to six novel genotypes. Mixed genotype was found in one isolate from goat in Sao Paulo. No classical clonal Type I. II or III isolates were found, confirming previous reports that these clonal lineages are rare in Brazil. The allele types at the CS3 locus are strongly linked to mouse virulence of the parasite. The results of this study indicate that even though a large number of T. gondii genotypes have been identified from a variety of animal hosts in Brazil, high percentage of new genotypes are continuously identified from different animal species, suggesting extremely high diversity of T. gondii in the population. (C) 2010 Elsevier B.V. All rights reserved.

Budget impact from the incorporation of positron emission tomography &#8211; computed tomography for staging lung cancers

OBJECTIVE To estimate the budget impact from the incorporation of positron emission tomography (PET) in mediastinal and distant staging of non-small cell lung cancer.METHODS The estimates were calculated by the epidemiological method for years 2014 to 2018. Nation-wide data were used about the incidence; data on distribution of the disease��s prevalence and on the technologies&#8217; accuracy were from the literature; data regarding involved costs were taken from a micro-costing study and from Brazilian Unified Health System (SUS) database. Two strategies for using PET were analyzed: the offer to all newly-diagnosed patients, and the restricted offer to the ones who had negative results in previous computed tomography (CT) exams. Univariate and extreme scenarios sensitivity analyses were conducted to evaluate the influence from sources of uncertainties in the parameters used.RESULTS The incorporation of PET-CT in SUS would imply the need for additional resources of 158.1 BRL (98.2 USD) million for the restricted offer and 202.7 BRL (125.9 USD) million for the inclusive offer in five years, with a difference of 44.6 BRL (27.7 USD) million between the two offer strategies within that period. In absolute terms, the total budget impact from its incorporation in SUS, in five years, would be 555 BRL (345 USD) and 600 BRL (372.8 USD) million, respectively. The costs from the PET-CT procedure were the most influential parameter in the results. In the most optimistic scenario, the additional budget impact would be reduced to 86.9 BRL (54 USD) and 103.8 BRL (64.5 USD) million, considering PET-CT for negative CT and PET-CT for all, respectively.CONCLUSIONS The incorporation of PET in the clinical staging of non-small cell lung cancer seems to be financially feasible considering the high budget of the Brazilian Ministry of Health. The potential reduction in the number of unnecessary surgeries may cause the available resources to be more efficiently allocated.

Avalia����o do desempenho de fundos de investimento de obriga����es: evid��ncia para o mercado Brasileiro

Disserta����o de mestrado em Finan��as

Intracortical connectivity of layer VI pyramidal cells in the barrel cortex of mice

ABSTRACT : The whisker-to-barrel pathway of rodents is formed by a series of somatotopic projections from the mystacial whisker follicles to the layer IV of the primary somatosensory cortex such that each follicle corresponds to a cluster of cortical neurons called barrel. Barrels are present in layer IV but form part of functional columns that comprise the entire depth of the somatosensory cortex. Interestingly, the cortex of the barrelless mouse strain (BRL) is organized such a manner that thalamocortical afferents do not remodel their projections in layer IV and barrels fail to appear. Nevertheless, functionally, a columnar organization persists, indicating that functional columns are not only provided by thalamocortical projections and layer IV cells. Since in the visual cortex of cats, layer VI cells contribute to the response properties of layer IV neurons, we wonder whether layer VI pyramidal cells could contribute to the columnar organization of the primary somatosensory cortex of mice. To address -this question, we morphologically analyzed the distribution of intracortical axon collaterals of layer VI neurons after in-vivo juxtacellular injections of biocytin in the C2 barrel column. Injected hemispheres were tangentially serial cut and intracortical collaterals of individual layer VI neurons were reconstructed at the light microscopic level. The position of axonal boutons was recorded to evaluate the distribution of presumed synaptic contacts. In normal (NOR) mice, cluster analysis shows that layer VI pyramidal cells can be classified in four statistically different clusters of neurons. Moreover, we assume that two classes are formed by cortico-cortical neurons and two classes are formed by cortico-thalamic neurons. Looking at the direction of the main axon in the white matter, we noticed that its orientation correlates perfectly with the type of neuron: cortico-cortical neurons send main axon medially whereas cortico-thalamic neurons send main axon laterally. Performing the same study in the BRL strain, we showed that the BRL mutation affects layer VI pyramidal cells tangentially and radially: the effects of the mutation are illustrated by a significant decrease of the index of colurnnarization and a significant decrease of percentage of boutons in granular and supragranular layers comparing to NOR neurons. In spite of these differences, the same four classes of layer VI neurons have been found in BRL mice. Using a tangential analysis of the boutons distribution, we showed that putative synapses are distributed mainly in the C2 barrel column. This was observed for each layer, type of neuron, cluster or strain, indicating that layer VI pyramidal cells could participate to the functional columnar organization of the barrel cortex. To determine post-synaptic partners of layer VI neurons in layer IV, we conducted an ultrastructural analysis of layer VI-to-IV contacts. We showed that synapses principally occur on spines and spiny dendritic shafts, supposed to belong to excitatory neurons. We furthermore showed that pre-synaptic elements are significantly different between en passant and terminaux contacts, which support hypothesis that terminaux boutons should show longer duration of facilitation than en passant boutons. R��SUM�� : Le ��whisker-to-barrel pathway�� des rongeurs est caract��ris�� par une s��rie de projections somatotopiques depuis les follicules des moustaches ('whiskers') jusqu'�� la couche IV de l'aire somatosensorielle primaire, de telle fa��on que chaque follicule corresponde �� un groupe de neurones corticaux appel��s tonneaux (`barrels'). Les tonneaux sont seulement pr��sents en couche IV mais font partie de colonnes fonctionnelles qui s'��tendent sur toute la profondeur du cortex somatosensoriel. Chez les souris mutantes barrelless (BRL), le cortex somatosensoriel est organis�� de fa��on telle que l��s aff��rences thalamocorticales ne remodellent pas leurs projections en couche IV et que les tonneaux n'apparaissent pas. Fonctionnellement, pourtant, une organisation en colonnes persiste, ce qui indique que les colonnes fonctionnelles ne sont pas uniquement produites par les projections thalamocorticales et par les cellules de la couche IV. Puisque les cellules de la couche VI contribuent �� influencer les r��ponses des cellules de la couche IV dans le cortex visuel du chat, nous nous sommes demand�� si ces cellules ne pourraient pas aussi contribuer �� l'organisation en colonnes du cortex somatosensoriel primaire de la souris. Pour r��pondre �� cette question, nous avons analys�� de fa��on morphologique la distribution intracorticale des collat��raux axonaux de neurones de la couche VI. Suite �� des injections juxtacellulaires de biocytine in-vivo dans la colonne C2, les h��misph��res c��r��braux ont ��t�� tangentiellement coup��s en s��rie et les collat��raux intracorticaux des neurones de la couche VI ont ��t�� reconstruits en microscopie optique. La position des boutons axonaux a aussi ��t�� enregistr��e pour ��valuer la distribution des contacts synpptiques potentiels. Chez les souris NOR, une analyse multivari��e montre que les cellules pyramidales de la couche VI sont distribu��es en quatre classes. Deux de ces classes sont probablement form��es de neurons cortico-corticaux, alors que les deux autres sont probablement form��es de neurones corticothalamiques. En observant la direction de l'axone principal dans la mati��re blanche, nous avons not�� que son orientation est parfaitement corr��l��e avec le type suppos�� de neurone : les neurones corticocorticaux envoient leurs axones principaux m��diallement, alors que les neurons cortico-thalamiques envoient leurs axones principaux lat��ralement. En menant la m��me ��tude chez les souris BRL, nous avons montr�� que la mutation affecte les cellules pyramidales de la couche VI de fa��on tangentielle, mais aussi radiaire : les effets de 1a mutation se traduisent par une diminution significative de l'index de �� columnarization �� et de la connectivit�� en couches granulaire et supragranulaire. Malgr�� ces diff��rences, les quatre m��mes classes de neurones ont ��t�� retrouv��es. En utilisant une analyse tangentielle de la distribution des boutons, nous avons montr�� que les synapses potentielles sont distribu��es principalement dans la colonne C2. Cette observation a ��t�� faite dans chaque couche, chaque type de neurones, chaque classe de neurones et chaque souche de souris, indicant que les cellules de la couche VI participent certainement �� l'organisation en colonne du cortex somatosensoriel. Pour d��terminer les partenaires post-synaptiques des cellules de la couche VI en couche IV, nous avons conduit une analyse ultrastructurelle de ces contacts. Nous avons montr�� que les synapses interviennent principalement sur les ��pines et sur les dendrites suppos��s appartenir �� des cellules excitatrices. Nous avons aussi montr�� que les ��l��ments pr��-synaptiques de ces synapses sont significativement differents selon le type de bouton, en passant ou terminal, ce qui supporte l'hypoth��se que les boutons terminaux seraient capables d'une plus longue facilitation.

Intracortical connectivity of layer VI pyramidal neurons in the somatosensory cortex of normal and barrelless mice.

In mice, barrels in layer IV of the somatosensory cortex correspond to the columnar representations of whisker follicles. In barrelless (BRL) mice, barrels are absent, but functionally, a columnar organization persists. Previously we characterized the aberrant geometry of thalamic projection of BRL mice using axonal reconstructions of individual neurons. Here we proceeded with the analysis of the intracortical projections from layer VI pyramidal neurons, to assess their contribution to the columnar organization. From series of tangential sections we reconstructed the axon collaterals of individual layer VI pyramidal neurons in the C2 barrel column that were labelled with biocytin [controls from normal (NOR) strain, 19 cells; BRL strain, nine cells]. Using six morphological parameters in a cluster analysis, we showed that layer VI neurons in NOR mice are distributed into four clusters distinguished by the radial and tangential extent of their intracortical projections. These clusters correlated with the cortical or subcortical projection of the main axon. In BRL mice, neurons were distributed within the same four clusters, but their projections to the granular and supragranular layers were significantly smaller and their tangential projection was less columnar than in NOR mice. However, in both strains the intracortical projections had a preference for the appropriate barrel column (C2), indicating that layer VI pyramidal cells could participate in the functional columnar organization of the barrel cortex. Correlative light and electron microscopy analyses provided morphometric data on the intracortical synaptic boutons and synapses of layer VI pyramidal neurons and revealed that projections to layer IV preferentially target excitatory dendritic spines and shafts.

Qualitative and quantitative analysis of thalamo-cortical axons in the somatosensory cortex of normal and barrelless mice

R��sum�� Les rongeurs utilisent leurs moustaches (vibrisses) pour explorer le milieu environnant. Chaque moustache est mue par un syst��me des muscles. Les r��cepteurs situ��s �� sa base transmettent les informations au syst��me nerveux central. La transmission vers l'��corce se fait via trois neurones de relais qui se trouvent au niveau du ganglion trig��min��, du tronc c��r��bral et du thalamus. La repr��sentation corticale d'une vibrisse est une concentration des axones thalamo-corticaux (ATC) autour desquelles s'organisent leurs cibles, les cellules de la couche IV. La structure peut ��tre identifi��e histologiquement en coupes tangentielles et porte le nom de �� barrel �� (�� tonneau ��). Cette correspondance vibrisse - barrel fait de ce syst��me un model id��al pour ��tudier l'influence de l'activit�� p��riph��rique sur l'��tablissement et le maintien des cartes somatotopiques. Notre laboratoire dispose d'une souche de souris qui a subi une mutation spontan��e pour le g��ne codant l'adenylyl cyclase I (ACI). Cette enzyme membranaire catalyse la formation de l'AMPc et joue un r��le important dans le guidage axonal, la lib��ration des neurotransmetteurs et l'int��gration des signaux postsynaptiques. Nous avons d��montr�� dans un premier temps que cette souris adulte ne d��veloppe pas de barrels. Cela est d�� �� un manque d'organisation des ATC et aussi des cellules de la couche IV. De plus, les r��sultats ��lectrophysiologiques montrent que les informations venant des vibrisses adjacentes ne sont pas int��gr��es d'une mani��re normale. Dans ce travail de th��se, j'ai analys�� la morphologie des ATC r��v��l��s individuellement avec de la biocytine. L'analyse quantitative des ATC a mis en ��vidence les points suivants: 1. Les axones de la souris normale (NOR) quittent le thalamus, traversent la capsule interne et la substance blanche sous-corticale et p��n��trent dans le cortex somato-sensoriel primaire. A l'int��rieur de l'��corce ils traversent au maximum 3 colonnes corticales adjacentes dont une contient le barrel cible. En passant �� travers les couches VI et V, ces axones arborisent et convergent progressivement vers le barrel dans lequel ils forment une riche arborisation. Un petit nombre des branches �� errantes ��, pleines de boutons synaptiques, p��n��trent dans les barrels voisins. Deux axones NOR provenant de corps cellulaires tr��s proches dans le thalamus peuvent avoir un cheminement tr��s divergent lors de la travers��e de la capsule interne et de la substance blanche sous-corticale mais, �� leur entr��e dans le cortex, ils sont distants d'au maximum 2 colonnes corticales de la colonne qui contient le barrel cible et ils convergent progressivement vers ce barrel. 2. Les axones de la souris mutante (BRL) ont le m��me trajet sous-cortical que les axones NOR, mais leur entr��e dans le cortex somato-sensoriel primaire est al��atoire. A l'interface entre la substance blanche sous-corticale et le cortex, l'axone principal se divise rapidement en troncs axonaux qui traversent les couches VI et V d'une mani��re divergente pour arriver dans la couche IV. Cela contraste beaucoup avec la trajectoire des NOR qui convergent graduellement vers leur barrel cible. Le nombre de branches radiales que les axones BRL utilisent pour entrer dans le cortex et dans la couche IV est double par rapport aux axones NOR. Parmi ces branches, seules quelques-unes donnent des arborisations, les autres ne sont pas d��velopp��es et leur morphologie est semblable �� celle des branches form��es par les axones de la souris normale lors du d��veloppement. Deux axones BRL issus de corps cellulaires proches dans le thalamus peuvent avoir une trajectoire tr��s divergente jusqu'�� leur entr��e dans la couche IV, mais �� ce niveau ils sont r��orient��s pour se retrouver et faire un nombre maximal de branches et boutons synaptiques dans la m��me r��gion corticale. Dans un cas extr��me, un des axones observ��s est entr�� dans le cortex �� la limite entre l'aire somatosensorielle primaire et secondaire et a parcouru une distance de 2 mm pour retrouver son partenaire thalamique et donner avec celui-ci un nombre maximal de branches dans la m��me r��gion de la couche IV. 3. Les mesures quantitatives ont montr�� que les arborisations corticales des axones NOR ont une longueur moyenne de 18mm et sont form��es par 200 segments qui portent 1200 boutons synaptiques. Par rapport �� la souris NOR, les axones BRL ont en moyenne la m��me longueur, le m��me nombre de segments et boutons synaptiques, mais donnent deux fois plus de branches radiales. La surface tangentielle occup��e par les arborisations BRL dans la couche IV est 2 fois plus grande que celle des NOR. Cela signifie que les 1000 boutons synaptiques qui caract��risent les arborisations NOR et BRL dans la couche IV sont diss��min��s sur une surface tangentielle double chez les derniers, et donc que la densit�� des boutons par unit�� de surface corticale est en moyenne plus faible. En effet, l'augmentation de la surface corticale tangentielle des BRL est due aux surfaces de faible et moyenne densit�� synaptique (0 - 8 boutons / 400pn2) qui augmentent 2 fois tandis que les surfaces de haute densit�� synaptiques (8 - 64 boutons / 4001.tm2) sont les m��mes. Nous ��mettons l'hypoth��se selon laquelle, durant le d��veloppement, les ATC de la souris BRL divergent et forment un nombre exub��rant de branches. Gr��ce �� cette divergence et aux branches supranum��raires, ils trouvent l'endroit de l'��corce o�� se trouvent leurs voisins thalamiques et arborisent abondamment dans cette r��gion. Cependant, le d��ficit en AGI ne leurs permet pas par la suite, sous influence de l'activit�� p��riph��rique, de retirer les branches qui se trouvent dans les endroits inappropri��s de l'��corce, avec de possibles cons��quences sur la discrimination tactile.

L'exp��rience des grands brûlés de la face : ��preuves sociales et travail de reconnaissance

L'��preuve �� factuelle �� et physique de la br��lure grave des grands brûlés de la face fait l'objet d'une analyse sociologique syst��matique : alors qu'un accident peut, en quelques secondes, provoquer une v��ritable rupture biographique, l'acceptation du nouveau statut et la �� reconstruction �� d'un rapport �� soi et aux autres prend beaucoup de temps. Les modalit��s de cette reconstruction et les tentatives pour retrouver une impossible �� apparence normale �� dans la vie publique sont ici analys��es. Tout en ��tant attentive aux modalit��s de l'interaction, la pr��sente ��tude rel��ve d'une d��marche sociologique compr��hensive men��e �� partir d'observations et d'entretiens conduits avec ces personnes, amenant dans le giron de la sociologie une exp��rience ��prouvanteencore peu connue, celle des grands brûlés de la face. Le registre discursif adoss�� �� cette derni��re vient compl��ter certaines repr��sentations v��hicul��es par les m��dias, les fictions et qui influent sur la perception et la visibilit�� de ceux-ci. A l'aune du concept d'��preuve issu de la �� sociologie pragmatique ��, le parcours du grand brûlé peut ��tre examin�� en pr��tant une attention particuli��re au moment initial du parcours post��br��lure : l'accident. La mise en r��cit de cette premi��re ��preuve est r��v��latrice des tentatives pour le grand brûlé de maintenir un lien entre un avant et un apr��s l'accident. S'ensuit un continuum d'��preuves intervenant d��s le moment o�� les grands brûlés se pr��sentent physiquement face �� autrui dans l'espace public suscitant des r��actions de g��ne et de malaise. Dans le prolongement des travaux d'Erving Goffman, on peut les concevoir comme des motifs d'�� inconfort interactionnel ��. Cette mise en ��vidence de l'inconfort interactionnel montre la n��cessit�� de ne pas se limiter �� une sociologie de la br��lure grave qui s'attarderait seulement sur les ajustements des interactions. A partir des travaux d'Axel Honneth sur la reconnaissance, il est possible de lire cette gestion des situations d'interaction dans une autre optique, celle qui, pour le grand brûlé, consiste �� se pr��server du m��pris. Ce travail met l'accent sur des habilet��s interactionnelles, des comp��tences qui fonctionnent comme des ressorts et permettent au grand brûlé de g��rer des situations susceptibles de conduire au m��pris. En s'appuyant sur des situations d'interaction racont��es, deux formes de lutte individuelle, de qu��te de reconnaissance, peuvent ��tre d��gag��es : d'une part, la �� lutte contre �� la trop grande visibilit�� et contre la pr��gnance de certains pr��jug��s et, d'autre part, la �� lutte pour �� faire conna��tre des aspects invisibles ou moins visibles de la br��lure grave. - This thesis analyzes the "factual" and physical ordeal of a severe burn as experienced by victims of severe facial burns. In a few seconds, an accident provokes a biographical rupture and persons involved need time to integrate their new status. This thesis concentrates on the "reconstruction" modes of the relationship with oneself and with others, and on attempts to find an impossible "normal appearance" in public life. While being attentive to the modalities of interaction, the study uses comprehensive sociology based on observations and interviews. This thesis brings into sociology litde known views of those suffering severe facial burns. These views supplement certain media representations that influence perceptions and visibility of the people involved. Applying the concept of test, a key concept of pragmatic sociology, the progression of a severely burned person can be described by focusing on the initial moment: the accident. The recounting of this first challenge reveals the severely burned person's efforts to link the "before" and "after" the accident. A continuum of challenges follows. These tests occur when the severely burned person physically faces others in a public space and when visible discomfort and embarrassment show, reactions which we consider, following Erving Goffman's works, as situations of "interactional discomfort." Emphasis on interactional discomfort shows the necessity of expanding the sociology of severe burns to more than just adjustments to interactions. Based on Axel Honneth's works, we can read the management of interactions from another point of view, in which the severely burned person tries to avoid contempt. This work emphasizes interactional aptitudes, skills that act like rebounding springs, and allow the severely burned person to manage situations that might lead to contempt. Starting with descriptions of interactions, we have determined two forms of individual struggle that appear to be a search for recognition: on one hand, the "struggle against" too much visibility and against the strength of certain prejudices, and, on the other hand, a "struggle for" making known rtain invisible or less visible aspects of a severe burn.

MARCADORES RAPD PARA MAPEAMENTO GEN��TICO E SELE����O DE H��BRIDOS DE CITROS

Os marcadores moleculares apresentam v��rias aplica����es no melhoramento de plantas, permitindo uma s��rie de an��lises gen��ticas. Este trabalho foi realizado com o objetivo de estabelecer marcadores RAPD para serem utilizados em estudos de mapeamento gen��tico e na sele����o de h��bridos entre tangerina-'Cravo' (Citrus reticulata Blanco) e laranja-'P��ra' (C. sinensis (L.) Osbeck). Extraiu-se DNA de folhas dos parentais e de seis h��bridos F1. As rea����es de amplifica����o foram preparadas em 13 uL de solu����o, constitu��da por tamp��o 1x GIBCO BRL; solu����es 1,54 mM de MgCl2 e 0,2 mM de cada dNTP; 15 ng de cada 'primer'; 1,5 unidade de 'Taq DNA Polymerase' e 15 ng de DNA gen��mico. As rea����es foram realizadas em termocicladores programados para 36 ciclos de 1 min a 92��C, 1 min a 36��C, 2 min a 72��C e 10 min de extens��o a 72��C. Foram testados 'primers' dec��meros arbitr��rios dos 'kits' A, AB, AT, AV, B, C, D, E, G, H, M, N, P, Q, R e U da Operon, sendo selecionados 113 por apresentarem polimorfismo, com n��mero de marcadores variando de 1 a 6 por 'primer'. Esses 'primers' amplificaram 201 (23,13%) bandas polim��rficas, aplic��veis no mapeamento gen��tico e sele����o de h��bridos. A freq����ncia de 'primers' com 1; 2; 3; 4; 5 e 6 bandas polim��rficas foi de 49,5%, 33,6%, 9,7%, 4,4%, 1,8% e 1,0%, respectivamente.