Cette thèse part de la proposition d\'une rencontre possible entre psychanalyse et génétique médicale par le biais des soins offerts aux enfants porteurs de syndromes génétiques, notamment le syndrome de l\'X fragile. Nous avons trouvé dans les recherches en épigénétique une voie de rapprochement de ces différents champs du savoir. L\'idée selon laquelle l\'environnement est capable de modifier l\'expression des gènes représente la rupture d\'un certain déterminisme génétique autrefois accepté, et ouvre un espace où penser la singularité. Notre travail propose d\'élargir le concept d\'environnement, en y considérant la relation de l\'enfant avec l\'Autre, lieu du langage, comme opérateur de marques sur son corps : marques symboliques, constituées dès le tout début de la rencontre de l\'infans et de ceux qui s\'occupent de lui. C\'est justement dans cet espace d\'échange avec l\'Autre qu\'a lieu l\'émergence d\'un sujet. Nous avons opté pour les concepts de sujet et de transfert pour soutenir l\'articulation de la clinique psychanalytique et de la génétique médicale en ce qui concerne le traitement. Nous avons donc exposé trois cas cliniques issus de notre pratique, d\'enfants traversés par le diagnostic de l\'X fragile afin d\'illustrer de quelle manière les conceptions de sujet et de transfert se reflètent dans la clinique. Tenant compte que la psychothérapie est également prise comme objet d\'étude de l\'épigénétique, et qu\'elle est donc considérée comme un environnement capable de provoquer, voire de renverser des marques épigénétiques, l\'enjeu de notre travail repose sur la proposition suivante : et pourquoi pas la psychanalyse également ? La psychothérapie psychanalytique, ancrée sur le transfert, ne peut-elle pas, elle aussi, laisser des marques sur le petit patient / The current thesis assumes a possible encounter between psychoanalysis and medical genetics based on the treatment applied to children carrying genetic syndromes such as the Fragile X Syndrome. Epigenetic studies are a way to approximate different knowledge fields. The assumption that the environment is able to change gene expression strays from the genetic determinism we once believed and opens the way for us to reason about singularity. The proposition in the present study lies on expanding the concept of environment, by taking into consideration the relation between the child and the Other in the environment in question, as well as the place of language as the operator marking the childs body. These symbolic marks start emerging in the first encounter between the infans and caregivers. The subject emerges precisely 3 within an environment of exchanges that is set with the Other. The concepts of subject and transference were chosen to support the treatment articulation between psychoanalytic clinic and medical genetics. Thus, the present study reports three clinical cases followed by the authors, which involved children diagnosed with fragile X syndrome. These cases illustrate how the aforementioned concepts affect the clinical practice. Since psychotherapy has also been taken as the object of epigenetic studies, and as it is considered an environment able to cause, and even reverse, epigenetic marks, the current study relies on the following proposition: why not psychoanalysis as well? Can the psychoanalytic psychotherapy, anchored in the concept of transference, leave marks on the little patient too?

Errata slip inserted at back / Bibliography: leaves 159-192 / vi, 142, [75] leaves : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Summary: Primary object ... was to construct a pulsed field gel electrophoresis (PFGE) derived long range restriction map of this region by physically linking adjacent DNA probes to common high molecular weight genomic DNA fragments / Thesis (Ph.D.)--University of Adelaide, Dept. of Paediatrics, 1994

The lipid kinase PI3K plays key roles in cellular responses to activation of receptor tyrosine kinases or G protein coupled receptors such as the metabotropic glutamate receptor (mGluR). Activation of the PI3K catalytic subunit p110 occurs when the PI3K regulatory subunit p85 binds to phosphotyrosine residues present in upstream activating proteins. In addition, Ras is uniquely capable of activating PI3K in a p85-independent manner by binding to p110 at amino acids distinct from those recognized by p85. Because Ras, like p85, is activated by phosphotyrosines in upstream activators, it can be difficult to determine if particular PI3K-dependent processes require p85 or Ras. Here we ask if PI3K requires Ras activity for either of two different PI3K-regulated processes within Drosophila larval motor neurons. To address this question, we determined the effects on each process of transgenes and chromosomal mutations that decrease Ras activity, or mutations that eliminate the ability of PI3K to respond to activated Ras. We found that PI3K requires Ras activity to decrease motor neuron excitability, an effect mediated by ligand activation of the single Drosophila mGluR DmGIuRA. In contrast, the ability of PI3K to increase synaptic bouton number is Ras independent. These results suggest that distinct regulatory mechanisms underlie the effects of PI3K on distinct phenotypic outputs. We additionally found that the glutamate-activation of DmGIuRA initiates ERK signaling; however the signaling intermediates linking DmGIuRA to this kinase cascade are unknown.

Fragile X Syndrome (FXS) is the leading cause of inherited intellectual disability. The disorder is caused by a trinucleotide expansion that silences the Fragile X Mental Retardation 1 (Fmr1) gene resulting in the loss of its protein product, the Fragile X Mental Retardation Protein (FMRP). FXS patients show broad clinical phenotypes including intellectual disability, as well as a number of cognitive and behavioral problems. The lack of FMRP is believed to be the direct cause of the deficits seen in FXS patients. FMRP is an RNA-binding protein that is expressed in the brain and testes. This protein is believed to form a messenger ribonucleoprotein complex with mRNAs in the nucleus and subsequently export them to polyribosomes in the cytoplasm, therefore influencing translation of its bound mRNAs. Importantly, FMRP has long been suspected to be involved in synaptic plasticity due to its ability to bind several mRNAs that encode for proteins important in synaptic plasticity. Such proteins include the GluN1, GluN2A and GluN2B subunits of the N-methyl-D- aspartate receptor (NMDAR). FMRP is expressed in the hippocampus, a region of the brain involved in learning and memory processes. Recently, impaired NMDAR functioning in the dentate gyrus (DG) subregion of the hippocampus has been observed in Fmr1 knockout (-/y) mice. This impairment also resulted in reduction in long-term potentiation (LTP) and long-term depression (LTD) of synaptic efficacy, two biological models of learning and memory. In the present study, I focused on the levels of the NMDAR GluN1, GluN2B and Glu2B subunits in order to determine the synaptic plasticity alterations seen in the DG of Fmr1-/y mice. Using Western blotting, I found that there is a decrease in the GluN1, GluN2A and GluN2B subunits in the DG of young adult Fmr1-/y mice, indicating that these mice have significantly lower amounts of total NMDARs. These results could explain the altered LTP and LTD seen in Fmr1-/y mice at the molecular level and might contribute to the intellectual impairments seen in these KO mice. NMDARs appear to be important in the development and maturation of synapses. The GluN2A and GluN2B subunits are developmentally regulated, where GluN2B is predominantly expressed early in development and GluN2A in the adult brain. A dysregulation of GluN2A and GluN2B subunits has been proposed to affect the maturation and formation of synapses. Intriguingly, FMRP is also believed to play a functional role in early brain development. Thus, this study also focused on the developmental expression of the GluN1, GluN2A and GluN2B subunits in the DG, Cornu Ammonis, prefrontal cortex and cerebellum of Fmr1-/y mice, all of which are brain regions implicated in FXS. We found that the developmental expression of these subunits is altered in Fmr1-/y mice in specific brain regions. Together, these results demonstrate that the loss of FMRP differentially affects GluN1, GluN2A and GluN2B subunit expression both developmentally and spatially, further implicating NMDARs in the pathophysiology of FXS. / Graduate

Thesis (Ph.D.)--University of Alabama at Birmingham, 2009. / Title from PDF title page (viewed on Sept. 10, 2009). Includes bibliographical references.

Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2012-07-25T21:04:26Z No. of bitstreams: 1 Marcela Kelly Astete Gómez Estudo dos alelos da região....pdf: 1187772 bytes, checksum: d35081c0e79dae64122fa5e5a15c60c3 (MD5) / Made available in DSpace on 2012-07-25T21:04:26Z (GMT). No. of bitstreams: 1 Marcela Kelly Astete Gómez Estudo dos alelos da região....pdf: 1187772 bytes, checksum: d35081c0e79dae64122fa5e5a15c60c3 (MD5) Previous issue date: 2011 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, Bahia, Brasil / A Síndrome do X-Frágil (SXF) é a principal causa hereditária de deficiência mental de herança dominante ligada ao cromossomo X. Em 1991, o gene FMR1 (Fragile X Mental Retardation 1) foi descoberto como responsável pela SXF. De acordo com o número de repetições, os alelos se dividem em: (a) alelo normal compreendendo 6 a 55 repetições (b) pré-mutado: 61 a 200 repetições e (c) mutado: com >200 repetições. Os alelos que apresentam 45 a 60 repetições são considerados como zona intermediária ou gray-zone. A base molecular dessa doença é bastante peculiar quando comparada com os padrões típicos observados em outras desordens de etiologia genética. As pré-mutações podem agregar-se de forma silenciosa por muitas gerações de uma família antes de se expandir para a mutação completa, levando aos sinais clínicos da doença. Na Bahia existem poucas pesquisas envolvendo esta doença, consequentemente, é desconhecida sua frequência nessa região. Portanto, este trabalho tem como objetivo detectar a frequência das classes alélicas do gene FMR1 em uma amostra de indivíduos do sexo masculino da população geral de Salvador-BA. Este estudo foi realizado em 511 homens provenientes de outro amplo estudo desenvolvido pelo Instituto de Saúde Coletiva (ISC) da Universidade Federal da Bahia (UFBA) sendo utilizada a técnica da PCR e posterior classificação dos alelos baseando-se na relação entre o número de repetições CGG e o tamanho do fragmento obtido na PCR. Dos 511 homens analisados no presente estudo observou-se predominância de alelos normais pertencentes à classe 2 (11 a 26 repetições CGG) em 73,70% dos indivíduos analisados, seguido da classe 3 (27 a 40 repetições CGG) em 25,10% dos indivíduos. Apenas 1,20% foram incluídos na classe 1 (<10 repetições CGG) e nenhum alelo foi encontrado nas classes 4 (41 a 60 repetições CGG), classe 5 ( >60 repetições CGG) e classe 6 (>200 repetições CGG). Este é o primeiro estudo utilizando a técnica da PCR para detecção dos alelos do gene FMR1 em uma população geral de Salvador-BA, podendo direcionar futuros trabalhos envolvendo o gene FMR1 tanto para o estado da Bahia, quanto para a região Nordeste e também minimizar deficiências existentes em termos de diagnóstico da SXF na cidade de Salvador-BA. / The Fragile X syndrome (FXS) is the leading cause of inherited mental deficiency (MD) of dominant inheritance linked to X chromosome. In 1991, the FMR1 gene (Fragile X Mental Retardation 1) was discovered as responsible for FXS. According to the number of repetitions, the alleles are divided in: (a) normal stable allele comprising 6 to 55 repetitions; (b) premutation: 61 to 200 repetitions and (c) mutant with> 200 repeats. The molecular basis of this disease is quite unusual when compared with the typical patterns seen in other disorders of genetic etiology. The pre-change can add up so silent for many generations of a family before they expand to full mutation, leading to clinical signs of disease. In Bahia there are few studies involving this disease, therefore, its frequency is unknown in this region. So, this study aims to detect the frequency of allelic classes of FMR1 gene in a sample of males from the general population of Salvador-BA city. This study was conducted on 511 samples using the PCR technique and subsequent classification of alleles based on the number of CGG repeats and the size of the fragments in PCR. Of the 511 individuals examined was found to predominate among the normal alleles the class 2 (11 to 26 repetitions) with 73,70% followed alleles analyzed in Class 3 (27 to 40 repetitions) with 25,10%, and Class 1 (<10 repetitions) with only one 1,20% . No allele was found in class 4 (41 to 60 repetitions), which corresponds to gray zone and class 5 (> 60 repetitions) for the premutation and class 6 (>200 repetitions) the corresponds full mutation.This is the first study using the PCR technique for detection of alleles of the FMR1 gene in a general population of Salvador, Bahia, and may direct future studies involving the FMR1 gene for both the state of Bahia, the Northeast and to also minimize deficiencies existing in the diagnosis of FXS in Salvador, Bahia.

O retardo mental (RM) representa um problema de saúde pública mundial ainda negligenciado no Brasil e, em especial nas regiões mais pobres como o Nordeste. A síndrome do X frágil (SXF) é uma das formas mais estudadas de RM hereditário em seres humanos. Esta doença monogênica, de herança ligada ao X dominante, é decorrente de uma mutação no exon 1 do gene FMR1, localizado na região Xq27.3. A mutação no FMR1 se caracteriza pelo aumento de repetições de trinucleotídios CGG em tandem na região 5 UTR desse gene, sendo a expansão dessas trincas o principal evento mutacional responsável pela SXF. De maneira geral, os fenótipos cognitivos de indivíduos do sexo masculino com a síndrome incluem deficiência intelectual de moderada à grave. No presente trabalho, realizamos um estudo transversal da SXF em indivíduos portadores de retardo mental de causa desconhecida, engajados em Programas de Educação Especial e em instituições psiquiátricas de São Luís-MA, rastreando amplificações de sequências trinucleotídicas no gene FMR1. A amostra foi composta por 238 indivíduos do sexo masculino, não aparentados, na faixa etária de 4 a 60 anos (média = 21 9 anos). O DNA dos participantes foi obtido a partir de 5 mL de sangue coletados em tubos com anti-coagulante EDTA e a análise molecular da região gênica de interesse foi realizada através da reação em cadeia da polimerase, utilizando-se três primers. Dentre os indivíduos triados quanto à presença de mutações no gene FMR1, apenas um apresentou um resultado inconclusivo e 2 (0,84%) foram positivos para a SXF, sendo que um deles (3503) apresentou mais de 200 repetições CGG no locus FRAXA e o outro indivíduo (3660) apresentou uma deleção de ~197 pb envolvendo parte das repetições CGG e uma região proximal às repetições CGG. Ambos possuíam história familiar de RM ligado ao X. No indivíduo 3503 observamos as seguintes características clínicas: temperamento dócil, orelhas grandes, mandíbula proeminente e flacidez ligamentar. O indivíduo 3660 apresentava hiperatividade, contato pobre com os olhos, orelhas grandes, mandíbula proeminente, pectus excavatum, macroorquidismo e pouca comunicação. O esclarecimento sobre a doença oferecido às famílias de ambos contribuiu sobremaneira para o entendimento da condição, do prognóstico e dos riscos de recorrência. A prevalência da SXF em nossa amostra, 0,84%, embora relativamente baixa, encontra-se na faixa de incidência de casos diagnosticados em outras populações que, em sua maioria, relatam incidências variando de 0 a 3%. Em parte, atribuímos o percentual encontrado aos critérios de inclusão utilizados em nosso estudo. Concluímos que o protocolo de triagem molecular utilizado em nosso estudo se mostrou eficiente e adequado para a realidade do Maranhão, podendo constituir uma ferramenta auxiliar a ser aplicada na avaliação de rotina dos portadores de RM, com grandes benefícios para o Estado. / Mental retardation (MR) is considered a global public health problem in Brazil and it is still ignored mainly in poor regions like Northeast Brazil. The fragile X syndrome (FXS) is one of the most common heritable disease in humans. it is a monogenic disease with X-linked dominant inheritance due to a mutation in exon 1 of the FMR1 gene, located at Xq27.3 region. The mutation in FMR1 is characterized by the increase in number of CGG repeats in the 5 'UTR of the gene. This expansion of CGG triplets in the first exon of the FMR1 gene is the main mutational event responsible for FXS. In general, the cognitive phenotypes of males with this syndrome include intellectual disabilities from moderate to severe. In this work, we conducted a cross-sectional study of FXS in individuals with MR of unknown cause, in Especial Education Programs and Psyquiatric Instituitions in São Luís-MA, by screening for amplifications of trinucleotide sequences within the FMR1 gene. The sample consisted of 238 unrelated males, which ages were from 4 to 60 years (mean = 21 9 years). The DNA of all individuals was obtained from 5 mL of peripheral blood which was colected in EDTA-anticoagulated tubes. The molecular analysis of the genetic region of interest was performed by polimerase chain reaction using three primers. Of the individuals screened for the presence of the mutation in the FMR1 gene, only one was inconclusive and two (0.84%) were positive for FXS. One (3503) presented more than 200 CGG repeats in FRAXA locus, and the other (3660) presented with a ~ 197 bp deletion involving part of CGG repeats and a proximal region to the CGG repeats. Both of these individuals have family history of X-linked Mental Retardation. The individual 3503 has the following clinical features: docile temperament, large ears, prominent jaw and ligamentous laxity. The individual 3660 presents hyperactivity, poor contact with eyes, large ears, prominent jaw, pectus excavatum, macroorchidism and little communication. Information about the disease helped the families of both individuals with FXS to understand the condition, the prognosis and about the recurrence risk. We found a FXS prevalence of 0.84% in our sample, although relatively low, it is in the range of incidence of diagnosed cases in other populations that report mostly incidences ranging from 0 to 3%. We partially attribute the percentage found due to the inclusion criteria used in our study. We conclude that the protocol for molecular screening used in our study proved to be efficient and appropriate to the reality of Maranhão, constituting an auxiliary tool to be applied in the routine assessment of patients with MR, with great benefits for the state.

O retardo mental (RM) representa um problema de saúde pública mundial ainda negligenciado no Brasil e, em especial nas regiões mais pobres como o Nordeste. A síndrome do X frágil (SXF) é uma das formas mais estudadas de RM hereditário em seres humanos. Esta doença monogênica, de herança ligada ao X dominante, é decorrente de uma mutação no exon 1 do gene FMR1, localizado na região Xq27.3. A mutação no FMR1 se caracteriza pelo aumento de repetições de trinucleotídios CGG em tandem na região 5 UTR desse gene, sendo a expansão dessas trincas o principal evento mutacional responsável pela SXF. De maneira geral, os fenótipos cognitivos de indivíduos do sexo masculino com a síndrome incluem deficiência intelectual de moderada à grave. No presente trabalho, realizamos um estudo transversal da SXF em indivíduos portadores de retardo mental de causa desconhecida, engajados em Programas de Educação Especial e em instituições psiquiátricas de São Luís-MA, rastreando amplificações de sequências trinucleotídicas no gene FMR1. A amostra foi composta por 238 indivíduos do sexo masculino, não aparentados, na faixa etária de 4 a 60 anos (média = 21 9 anos). O DNA dos participantes foi obtido a partir de 5 mL de sangue coletados em tubos com anti-coagulante EDTA e a análise molecular da região gênica de interesse foi realizada através da reação em cadeia da polimerase, utilizando-se três primers. Dentre os indivíduos triados quanto à presença de mutações no gene FMR1, apenas um apresentou um resultado inconclusivo e 2 (0,84%) foram positivos para a SXF, sendo que um deles (3503) apresentou mais de 200 repetições CGG no locus FRAXA e o outro indivíduo (3660) apresentou uma deleção de ~197 pb envolvendo parte das repetições CGG e uma região proximal às repetições CGG. Ambos possuíam história familiar de RM ligado ao X. No indivíduo 3503 observamos as seguintes características clínicas: temperamento dócil, orelhas grandes, mandíbula proeminente e flacidez ligamentar. O indivíduo 3660 apresentava hiperatividade, contato pobre com os olhos, orelhas grandes, mandíbula proeminente, pectus excavatum, macroorquidismo e pouca comunicação. O esclarecimento sobre a doença oferecido às famílias de ambos contribuiu sobremaneira para o entendimento da condição, do prognóstico e dos riscos de recorrência. A prevalência da SXF em nossa amostra, 0,84%, embora relativamente baixa, encontra-se na faixa de incidência de casos diagnosticados em outras populações que, em sua maioria, relatam incidências variando de 0 a 3%. Em parte, atribuímos o percentual encontrado aos critérios de inclusão utilizados em nosso estudo. Concluímos que o protocolo de triagem molecular utilizado em nosso estudo se mostrou eficiente e adequado para a realidade do Maranhão, podendo constituir uma ferramenta auxiliar a ser aplicada na avaliação de rotina dos portadores de RM, com grandes benefícios para o Estado. / Mental retardation (MR) is considered a global public health problem in Brazil and it is still ignored mainly in poor regions like Northeast Brazil. The fragile X syndrome (FXS) is one of the most common heritable disease in humans. it is a monogenic disease with X-linked dominant inheritance due to a mutation in exon 1 of the FMR1 gene, located at Xq27.3 region. The mutation in FMR1 is characterized by the increase in number of CGG repeats in the 5 'UTR of the gene. This expansion of CGG triplets in the first exon of the FMR1 gene is the main mutational event responsible for FXS. In general, the cognitive phenotypes of males with this syndrome include intellectual disabilities from moderate to severe. In this work, we conducted a cross-sectional study of FXS in individuals with MR of unknown cause, in Especial Education Programs and Psyquiatric Instituitions in São Luís-MA, by screening for amplifications of trinucleotide sequences within the FMR1 gene. The sample consisted of 238 unrelated males, which ages were from 4 to 60 years (mean = 21 9 years). The DNA of all individuals was obtained from 5 mL of peripheral blood which was colected in EDTA-anticoagulated tubes. The molecular analysis of the genetic region of interest was performed by polimerase chain reaction using three primers. Of the individuals screened for the presence of the mutation in the FMR1 gene, only one was inconclusive and two (0.84%) were positive for FXS. One (3503) presented more than 200 CGG repeats in FRAXA locus, and the other (3660) presented with a ~ 197 bp deletion involving part of CGG repeats and a proximal region to the CGG repeats. Both of these individuals have family history of X-linked Mental Retardation. The individual 3503 has the following clinical features: docile temperament, large ears, prominent jaw and ligamentous laxity. The individual 3660 presents hyperactivity, poor contact with eyes, large ears, prominent jaw, pectus excavatum, macroorchidism and little communication. Information about the disease helped the families of both individuals with FXS to understand the condition, the prognosis and about the recurrence risk. We found a FXS prevalence of 0.84% in our sample, although relatively low, it is in the range of incidence of diagnosed cases in other populations that report mostly incidences ranging from 0 to 3%. We partially attribute the percentage found due to the inclusion criteria used in our study. We conclude that the protocol for molecular screening used in our study proved to be efficient and appropriate to the reality of Maranhão, constituting an auxiliary tool to be applied in the routine assessment of patients with MR, with great benefits for the state.

Cette thèse part de la proposition d\'une rencontre possible entre psychanalyse et génétique médicale par le biais des soins offerts aux enfants porteurs de syndromes génétiques, notamment le syndrome de l\'X fragile. Nous avons trouvé dans les recherches en épigénétique une voie de rapprochement de ces différents champs du savoir. L\'idée selon laquelle l\'environnement est capable de modifier l\'expression des gènes représente la rupture d\'un certain déterminisme génétique autrefois accepté, et ouvre un espace où penser la singularité. Notre travail propose d\'élargir le concept d\'environnement, en y considérant la relation de l\'enfant avec l\'Autre, lieu du langage, comme opérateur de marques sur son corps : marques symboliques, constituées dès le tout début de la rencontre de l\'infans et de ceux qui s\'occupent de lui. C\'est justement dans cet espace d\'échange avec l\'Autre qu\'a lieu l\'émergence d\'un sujet. Nous avons opté pour les concepts de sujet et de transfert pour soutenir l\'articulation de la clinique psychanalytique et de la génétique médicale en ce qui concerne le traitement. Nous avons donc exposé trois cas cliniques issus de notre pratique, d\'enfants traversés par le diagnostic de l\'X fragile afin d\'illustrer de quelle manière les conceptions de sujet et de transfert se reflètent dans la clinique. Tenant compte que la psychothérapie est également prise comme objet d\'étude de l\'épigénétique, et qu\'elle est donc considérée comme un environnement capable de provoquer, voire de renverser des marques épigénétiques, l\'enjeu de notre travail repose sur la proposition suivante : et pourquoi pas la psychanalyse également ? La psychothérapie psychanalytique, ancrée sur le transfert, ne peut-elle pas, elle aussi, laisser des marques sur le petit patient / The current thesis assumes a possible encounter between psychoanalysis and medical genetics based on the treatment applied to children carrying genetic syndromes such as the Fragile X Syndrome. Epigenetic studies are a way to approximate different knowledge fields. The assumption that the environment is able to change gene expression strays from the genetic determinism we once believed and opens the way for us to reason about singularity. The proposition in the present study lies on expanding the concept of environment, by taking into consideration the relation between the child and the Other in the environment in question, as well as the place of language as the operator marking the childs body. These symbolic marks start emerging in the first encounter between the infans and caregivers. The subject emerges precisely 3 within an environment of exchanges that is set with the Other. The concepts of subject and transference were chosen to support the treatment articulation between psychoanalytic clinic and medical genetics. Thus, the present study reports three clinical cases followed by the authors, which involved children diagnosed with fragile X syndrome. These cases illustrate how the aforementioned concepts affect the clinical practice. Since psychotherapy has also been taken as the object of epigenetic studies, and as it is considered an environment able to cause, and even reverse, epigenetic marks, the current study relies on the following proposition: why not psychoanalysis as well? Can the psychoanalytic psychotherapy, anchored in the concept of transference, leave marks on the little patient too?

<p>Intricate neural circuits underlie all brain functions. However, these neural circuits are highly dynamic. The ability to change, or the plasticity, of the brain has long been demonstrated at the level of isolated single synapses under artificial conditions. Circuit organization and brain function has been extensively studied by correlating neuronal activity with information input. The primary visual cortex has become an important model brain region for the study of sensory processing, in large part due to the ease of manipulating visual stimuli. Much has been learned from studies of visual cortex focused on understanding the signal-processing of visual inputs within neural circuits. Many of these findings are generalizable to other sensory systems and other regions of cortex. However, few studies have directly demonstrated the orchestrated neural-circuit plasticity occurring during behavioral experience. </p> <p>It is vital to measure the precise circuit connectivity and to quantitatively characterize experience-dependent circuit plasticity to understand the processes of learning and memory formation. Moreover, it is important to study how circuit connectivity and plasticity in neurological and psychiatric disease states deviates from that in healthy brains. By understanding the impact of disease on circuit plasticity, it may be possible to develop therapeutic interventions to alleviate significant neurological and psychiatric morbidity. In the case of neural trauma or ischemic injury, where neurons and their connections are lost, functional recovery relies on neural-circuit repair. Evaluating whether neurons are reconnected into the local circuitry to re-establish the lost connectivity is crucial for guiding therapeutic development.</p> <p>There are several major technical hurdles for studies aiming to quantify circuit connectivity. First, the lack of high-specificity circuit stimulation methods and second, the low throughput of the gold-standard patch-clamp technique for measuring synaptic events have limited progress in this area. To address these problems, we first engineered the patch-clamp experimental system to automate the patching process, increasing the throughput and consistency of patch-clamp electrophysiology while retaining compatibility of the system for experiments in <i>ex vivo </i>brain slices. We also took advantage of optogenetics, the technology that enables control of neural activity with light through ectopic expression of genetically encoded photo-sensitive channels in targeted neuronal populations. Combining optogenetic stimulation of pre-synaptic axonal terminals and whole-cell patch-clamp recording of post-synaptic currents, we mapped the distribution and strength of synaptic connections from a specific group of neurons onto a single cell. With the improved patch-clamp efficiency using our automated system, we efficiently mapped a significant number of neurons in different experimental conditions/treatments. This approach yielded large datasets, with sufficient power to make meaningful comparisons between groups.</p> <p>Using this method, we first studied visual experience-dependent circuit plasticity in the primary visual cortex. We measured the connectivity of local feedback and recurrent neural projections in a Fragile X syndrome mouse model and their healthy counterparts, with or without a specific visual experience. We found that repeated visual experience led to increased excitatory drive onto inhibitory interneurons and intrinsically bursting neurons in healthy animals. Potentiation at these synapses was absent or abnormal in Fragile X animals. Furthermore, recurrent excitatory input onto regular spiking neurons within the same layer remained stable in healthy animals but was depressed in Fragile X animals following repeated visual experience. These results support the hypothesis that visual experience leads to selective circuit plasticity which may underlie the mechanism of visual learning. This circuit plasticity process is impaired in a mouse model of Fragile X syndrome. </p> <p>In a separate study, in collaboration with the laboratory of Dr. Gong Chen, we applied the circuit-mapping method to measure the effect of a novel brain-repair therapy on functional circuit recovery following ischemic injury, which locally kills neurons and creates a glial scar. By directly reprogramming astrocytes into neurons within the region of the glial scar, this gene-therapy technology aims to restore the local circuit and thereby dramatically improve behavioral function after devastating neurological injury. We found that direct reprogramming converted astrocytes into neurons, and importantly, we found that these newly reprogrammed neurons integrated appropriately into the local circuit. The reprogramming also improved connections between surviving endogenous neurons at the injury site toward normal healthy levels of connectivity. Connections formed onto the newly reprogrammed neurons spontaneously remodeled, the process of which resembled neural development. By directly demonstrating functional connectivity of newly reprogrammed neurons, our results suggest that this direct reprogramming gene-therapy technology holds significant promise for future clinical application to restore circuit connectivity and neurological function following brain injury.</p>