Spelling suggestions: "subject:"lobe"" "subject:"obe""
191 |
Inhibitory-excitatory imbalance in hippocampal subfield cornu ammonis 2 circuitry in a mouse model of temporal lobe epilepsyWhitebirch, Alexander Craig January 2021 (has links)
Temporal lobe epilepsy (TLE) is among the most common forms of epilepsy in adults. A significant proportion of patients experience drug-resistant seizures associated with hippocampal sclerosis (HS), in which there is extensive cell loss in the hippocampal cornu ammonis 1 (CA1) and cornu ammonis 3 (CA3) subfields. The dentate gyrus (DG) and cornu ammonis 2 (CA2) subfield are more resilient to neurodegeneration, and a prior report found that CA2 neurons in tissue from TLE patients show interictal-like firing and receive aberrant perisomatic excitatory synapses from DG granule cell (GC) mossy fibers (Wittner et al. Brain. 2009;132:3032–3046). Furthermore, findings from a collaborative study in the laboratory of Dr. Helen Scharfman demonstrated that chronic chemogenetic inhibition of CA2 pyramidal neurons (PNs) in vivo significantly reduced the frequency of spontaneous recurring convulsive seizures in epileptic mice. I therefore explored the hypothesis that pathophysiological changes to CA2 PN excitability or synaptic connectivity may be associated with chronic epilepsy by examining CA2 properties in a mouse model of TLE.Pilocarpine-induced status epilepticus in mice leads to a pattern of hippocampal sclerosis-like neurodegeneration and recurring spontaneous seizures, and thus recapitulates key features of TLE. I performed whole-cell electrophysiological recordings from PNs in acute hippocampal slices from pilocarpine (PILO)-treated mice in the chronic phase of epilepsy as well as age-matched controls. In some experiments I used Cre-expressing mouse lines to selectively express a light-activated excitatory channel in CA2 PNs or DG GCs. I also performed immunohistochemistry to examine CA2 interneuron (IN) populations following PILO-induced status epilepticus.
I found that in healthy tissue CA2 PNs, like those in CA3, both directly excited other CA2 PNs via a recurrent CA2-CA2 PN circuit and indirectly inhibited other CA2 PNs by recruiting local INs. The CA2 and CA3 subfields also form reciprocal excitatory and feedforward inhibitory circuits. These recurrent and reciprocal circuits constitute an auto-associative network in which INs crucially control CA2/CA3 population excitability. DG GC mossy fibers made direct but relatively weak excitatory synapses onto CA2 PNs.
Following PILO-induced status epilepticus, feedforward inhibition is diminished in the DG GC mossy fiber circuit to CA2, in the CA2/CA3 recurrent network, and in the forward-projecting circuit from CA2 PNs to CA1. I found a modest decrease in the density of parvalbumin-immunopositive INs and a profound decrease of cholecystokinin-immunopositive IN density, combined with degradation of the pyramidal neuron-associated perisomatic perineuronal net, which together may contribute to this inhibitory disruption. DG GC mossy fiber excitatory input to CA2 PNs is strengthened, along with CA2 PN excitatory input to CA1 PNs. Finally, in hippocampal slices from PILO-treated mice I found an increase in CA2 PN input resistance and thus elevated intrinsic excitability, leading to a higher firing rate upon direct current injection. The combined effect of these changes may drive the emergence of epileptiform synchronization in the CA2 network and facilitate the propagation of seizure activity from the DG and entorhinal cortex directly to CA1 via the CA2-centered disynaptic (EC LII --> CA2 --> CA1) and alternate trisynaptic circuits (EC LII --> DG --> CA2 --> CA1).
|
192 |
Ovarian Morphology, Oogenesis, and Changes through the Annual Reproductive Cycle of the Female Blue Crab, <em>Callinectes sapidus</em> Rathbun, in Tampa BayBrown, Catalina E 10 April 2009 (has links)
The blue crab, Callinectes sapidus Rathbun, 1896, was studied because of its high dollar value to Florida's commercial and recreational fisheries. The purpose of this study was to describe the structure of the ovary and oogenesis in the blue crab and the morphological changes in the female reproductive developmental stages over time. Histological techniques for high-resolution light microscopy were used to determine sexual maturity of female blue crabs. The ovarian morphology, oogenesis, and changes through the annual reproductive cycle of blue crabs in Tampa Bay were investigated for a period of two years, from January 2005 to January 2007. Ovarian structure was assessed by analyzing histological sections embedded in plastic epoxy resin, which provided a higher resolution than any other embedding material previously used in research on blue crab reproduction. Qualitative analyses of female gonads were made by describing the structure of the oocytes and determining the developmental stage of the oocytes from oogonia to full-grown oocytes. This study developed and introduced a new reproductive staging criteria for the species. Morphological characteristics of ovarian tissues and oocytes were determined to develop a classification for oocyte maturation stages. Morphological changes in the oocytes are well defined, and these were used to develop the staging schema.
In this study, it was found that carapace width is not a good indicator of maturity or developmental stage. Examination of the annual reproductive cycle indicates that late secondary growth occurs from July to March, and gravid crabs were found during November and December. Histological examination of ovarian tissue is essential for determining maturity in female blue crabs. By observing ovarian characteristics and by establishing the length of secondary growth during oogenesis in blue crabs of Tampa Bay, a more thorough understanding of the cyclic reproductive aspects of this species was obtained and specifically that animals at a carapace width between 100 mm and 125 mm may have mature oocytes, yet external features may not indicate that they are mature.
|
193 |
Evaluation of Novel Scoring System in the Detection of Lateralized Deficits in Temporal Lobe EpilepsyPrabhu, Hema 25 May 2022 (has links)
No description available.
|
194 |
Fonctions exécutives et cognition sociale chez des patients traités dans l’enfance pour une tumeur frontale bénigne ou maligne / Frontal lobe tumours in children and adolescents : executive function and theory of mindLongaud-Valès, Audrey 17 June 2013 (has links)
En neuro-oncologie pédiatrique, les études neurocognitives et neuropsychologiques sur les tumeurs hémisphériques (sus-tentorielles) sont plus rares que celles sur les tumeurs de la fosse postérieure (sous-tentorielles), bénignes (notamment l’astrocytome pilocytique du cervelet) ou malignes (en particulier, le médulloblastome qui est la tumeur maligne la plus fréquente chez l’enfant). A l’heure actuelle il n’existe pas, à notre connaissance, de séries publiées de cas d’enfants traités pour tumeur frontale, bénigne ou maligne et même les descriptions isolées d’un seul cas restent rares (Daigneault, S & al, 1997 ; Anderson, S.W, 2000). Il existe des séries de cas de tumeur frontale chez l’adulte (Roca & al, 2010 ; Yong-Gao & al, 2012). Il existe par contre une littérature importante porte sur le devenir et les séquelles des enfants traités pour une tumeur de la fosse postérieure. En effet, les progrès thérapeutiques ont amélioré les taux de survie, et plusieurs équipes ont examinés l’impact de différents facteurs (essentiellement mais pas exclusivement médicaux : topographie lésionnelle, âge d’apparition de la tumeur, nature des traitements et complications, etc., mais aussi niveau d’éducation des parents, etc.) sur les séquelles motrices et cognitives, le devenir et la qualité de vie de ces enfants et adolescents. Entre septembre 2010 et septembre 2011, 21 patients âgés entre 8 ans 3 mois et 27 ans 10 mois au moment de l’évaluation neuropsychologique ont été inclus dans cette étude. L’évaluation neuropsychologique, réalisée en deux temps, incluait des tests (tests papier-crayon et épreuves écologiques) évaluant l’efficience intellectuelle, des fonctions exécutives, d’attention, et de théorie de l’esprit. 44 patients contrôles ont été appariés en âge, sexe et NSC (niveau socio-économique) au groupe de patients. Au niveau statistique d’importantes différences sont relevées, notamment, dans les épreuves de reconnaissance d’expressions faciales émotionnelles. Il s’agit de la 1ère étude qui évalue les fonctions cognitives et affectives dans un groupe de patients ayant été traités dans l’enfance pour une tumeur frontale bénigne ou maligne. / Frontal lesions in children and adolescents have been mainly explored in traumatic brain injury (TBI). Other frontal lobe pathologies such as frontal lobe epilepsy (FLE), frontal focal lobe lesion, such as brain tumours or frontal focal lobe pathologies, can explain sequelae after frontal lobe pathologies. In the literature only two cases studies exist on benign frontal lobe tumour in children. To our knowledge there is no study group of frontal lobe tumours in children. Between September 2010 and September 2011, we observed 21 patients treated for benign/malign tumours. We examined 22 young patients aged between 8.3 years and 27.10 years old, all treated for benign or malign frontal tumour in Gustave Roussy’s Institute (in case of malign tumour) or Necker Enfants-Malades (in case of malign tumour). Treatment of this patients depended on benign or malign tumour. A total of 44 controls subjects were enrolled in study. All children and adolescents had neuropsychological tests, such as executive function tests (planning, mental flexibility, attention, working memory tasks) and measure or theory of mind tests such as face recognition test (TOM). All children were seen twice. Main differences are observed in facial recognition test between patients with malign and benign tumours and control subjects. IQ in not affected when tumours are benign, and most children obtain normal performances in executive tests. This is a first study with comprehensive neuropsychological assessment of children and adolescents with frontal lobe tumours. Findings have to be compared with classical studies of frontal lobe lesions in adults. Results suggest that many children treated for frontal lobe tumours do not present the classical dysexecutive syndrome and major behavioural changes as described in adults. However most of them present deficits in facial recognition of emotions and gesture imitations deficits.
|
195 |
Evaluation of Focus Laterality in Temporal Lobe Epilepsy: A Quantitative Study Comparing Double Inversion-Recovery MR Imaging at 3T with FDG-PET / 側頭葉てんかんにおける焦点側の画像診断: 3T MRIを用いたDouble Inversion-Recovery法とFDG-PETとの定量的比較Morimoto, Emiko 23 May 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18451号 / 医博第3906号 / 新制||医||1004(附属図書館) / 31329 / 京都大学大学院医学研究科医学専攻 / (主査)教授 福山 秀直, 教授 村井 俊哉, 教授 平岡 眞寛 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DGAM
|
196 |
Direct Exploration of the Role of the Ventral Anterior Temporal Lobe in Semantic Memory: Cortical Stimulation and Local Field Potential Evidence From Subdural Grid Electrodes / 意味記憶に関する側頭葉底部前方領域の直接的検索:皮質電気刺激と硬膜下電極記録の局所電場電位からの証左Shimotake, Akihiro 24 September 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第19272号 / 医博第4036号 / 新制||医||1011(附属図書館) / 32274 / 京都大学大学院医学研究科医学専攻 / (主査)教授 高橋 淳, 教授 村井 俊哉, 教授 渡邉 大 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
|
197 |
Sleep modulates cortical connectivity and excitability in humans: direct evidence from neural activity induced by single-pulse electrical stimulation / 睡眠はヒトの大脳皮質の結合性と興奮性を変容させる:単発の皮質電気刺激で誘発される神経活動の解析からの証左Usami, Kiyohide 24 November 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第19366号 / 医博第4043号 / 新制||医||1011(附属図書館) / 32380 / 新制||医||1011 / 京都大学大学院医学研究科医学専攻 / (主査)教授 渡邉 大, 教授 福田 和彦, 教授 村井 俊哉 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
|
198 |
Network specific change in white matter integrity in mesial temporal lobe epilepsy / 内側側頭葉てんかんにおけるネットワーク特異的な白質統合性の変化Imamura, Hisaji 24 July 2017 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第13120号 / 論医博第2133号 / 新制||医||1023(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 高橋 淳, 教授 村井 俊哉, 教授 林 康紀 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
|
199 |
Magnetoencephalography with temporal spread imaging to visualize propagation of epileptic activity / Temporal spread imaging法を用いた脳磁図解析による、てんかん性活動伝播の描出Shibata, Sumiya 24 July 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20610号 / 医博第4259号 / 新制||医||1023(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 村井 俊哉, 教授 渡邉 大, 教授 林 康紀 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
|
200 |
The Contribution of Visuospatial Functioning to Verbal Paired Associate Learning in Temporal Lobe EpilepsyFiumedora, Marianne 30 October 2018 (has links)
No description available.
|
Page generated in 0.0343 seconds