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We report a case of a 67-year-old man with left thalamic hemorrhage. He had right hemiplegia, aphasia, and higher brain dysfunction. The hemiplegia and aphasia improved with rehabilitation treatment；however, he was unable to perform activities of daily living. Visual and tactile agnosia was suspected using the visual perception test for agnosia 1 month after the hemorrhage. The patient was able to recognize common objects, such as chopsticks and a shaver, by labeling them with their names because he could read words. He was able to use these objects as a result. Multimodal agnosia with combined visual-tactile agnosia usually occurs as lesions in and around the left lateral occipital complex where the ventral stream of somatosensory information processing merges with that of visual information processing. Concurrently, the present case seems very unusual because multimodal agnosia was likely to have occurred as a lesion of the left thalamus. The compensatory strategy to put objects into words was effective in this case. We repeatedly assessed and analyzed his higher brain dysfunction in detail, which led to effective rehabilitation treatment. The present case highlights the importance of planning an appropriate treatment based on detailed evaluation and accurate diagnosis of the higher brain dysfunction in patients with neurological deficits.
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We report a case of a 67-year-old man with left thalamic hemorrhage. He had right hemiplegia, aphasia, and higher brain dysfunction. The hemiplegia and aphasia improved with rehabilitation treatment；however, he was unable to perform activities of daily living. Visual and tactile agnosia was suspected using the visual perception test for agnosia 1 month after the hemorrhage. The patient was able to recognize common objects, such as chopsticks and a shaver, by labeling them with their names because he could read words. He was able to use these objects as a result. Multimodal agnosia with combined visual-tactile agnosia usually occurs as lesions in and around the left lateral occipital complex where the ventral stream of somatosensory information processing merges with that of visual information processing. Concurrently, the present case seems very unusual because multimodal agnosia was likely to have occurred as a lesion of the left thalamus. The compensatory strategy to put objects into words was effective in this case. We repeatedly assessed and analyzed his higher brain dysfunction in detail, which led to effective rehabilitation treatment. The present case highlights the importance of planning an appropriate treatment based on detailed evaluation and accurate diagnosis of the higher brain dysfunction in patients with neurological deficits.
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This study explored the effects of propofol on the activity of glutamatergic neurons in the paraventricular thalamus (PVT) and the underlying mechanisms at the molecular level using whole-cell patch-clamp techniques. Acute brain slices containing the PVT were obtained from 8 weeks old C57BL/6J mice. The electrophysiological characteristics of PVT neurons were recorded in current-clamp mode, then single-cell sequencing was used to identify neuronal types. The firing frequencies before, during, and after propofol or intralipid application were recorded as FB, FD and FW; and the membrane potentials were recorded as MPB and MPD. Picrotoxin (PTX) was used to block inhibitory gamma-aminobutyric acid type A (GABAA) receptors during the application of propofol at 10 μmol·L-1. Then, GABAA receptor-mediated spontaneous and miniature inhibitory postsynaptic currents (sIPSCs and mIPSCs) were recorded, and the effects of 10 μmol·L-1 propofol were investigated. The animal experiments were approved by the Medical Animal Administrative Committee of Shanghai Medical College Fudan University. The results showed that there were no significant differences in FB, FD and FW during intralipid and 2 μmol·L-1 propofol application. With propofol at 5, 10 and 20 μmol·L-1, FD decreased significantly when compared with FB, and FW increased significantly as compared with FD (P < 0.01). The inhibition degree of the three concentration groups was significantly different (P < 0.01). In addition, with propofol at 20 μmol·L-1, MPD hyperpolarized significantly (P < 0.01). In the presence of PTX, 10 μmol·L-1 propofol could not suppress the firing frequency of PVT glutamatergic neurons. Propofol at 10 μmol·L-1 prolonged the decay time of sIPSCs (P < 0.01) and mIPSCs (P < 0.05), and increased the amplitude (P < 0.01) of mIPSCs of PVT glutamatergic neurons. Together, these results indicate that propofol can inhibit the activity of PVT glutamatergic neurons in a concentration-dependent and reversible manner, and the effect is likely to be mediated by postsynaptic GABAA receptors.
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【Objective】 To investigate changes in thalamus structure and function and their associations with cognitive impairment in patients with amyotrophic lateral sclerosis (ALS). 【Methods】 3D high-resolution structural imaging and resting-state fMRI were applied in 78 ALS patients and 49 healthy volunteers. The shape of the thalamus was assessed using a vortex analysis and functional connectivity between the thalamus subregion and cortex was evaluated by a seed-based correlation analysis. Partial correlation analysis was used to evaluate the correlation between focal thalamus alterations and clinical assessments. 【Results】 Compared with the control group, vertex analysis showed significant atrophy in the prefrontal and temporal subregions of bilateral thalamus in the ALS group. Patients exhibited increased functional connectivity of motor-sensory ROI with the right motor cortex, of temporal ROI with the bilateral lateral occipital cortex, precuneus and right temporal subregion. In contrast, decreased function connectivity was found mainly between temporal ROI and paracingulate gyrus, left dorsomedial prefrontal lobe and left caudate. Partial correlation analysis showed that the functional connectivity of the precuneus, paracingulate cortex, left caudate nucleus and left prefrontal lobe was correlated with multiple cognitive performances. 【Conclusion】 Selective damage of thalamic structure and function in ALS plays an important role in cognitive and behavioral disorders.
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Objective:To investigate the neurobiochemical metabolites of caudate nucleus and thalamus in patients with obsessive-compulsive disorder and their relationship with obsessive-compulsive symptoms.Methods:From April 2019 to January 2022 in Beijing Anding Hospital, totally 25 untreated patients with obsessive-compulsive disorder were recruited, and 20 healthy controls matched with gender, age and educational background were recruited for the study.The maps of neurobiochemical metabolites of patients and normal controls were collected by hydrogen proton magnetic resonance spectroscopy.With bilateral caudate nucleus and thalamus as brain regions of interest.The relative concentrations of N-acetylaspartic acid (NAA), glutamic acid (Glu) and γ-aminobutyric acid (GABA) were fitted by LCModel software.At the same time, the clinical symptoms of patients were evaluated with Yale-Brown obsessive-compulsive scale (Y-BOCS) and Hamilton anxiety scale (HAMA). SPSS 20.0 software was used for statistical analysis.Independent double sample t-test was used to compare the differences of different nerve biochemical metabolite concentrations between patients with obsessive-compulsive disorders and healthy controls.Pearson correlation analysis was used to explore the correlation between biochemical metabolite concentrations and clinical symptoms. Results:The Glu concentration in the left thalamus of patients with obsessive-compulsive disorder (3.97±0.41) was higher than that of the control group (3.66±0.55)( t=-2.11, P<0.05), while the NAA concentration was (4.87±0.47)lower than that of the control group (5.15±0.44)( t=2.05, P<0.05). The GABA concentrations in the right caudate nucleus (0.50±0.18) and thalamus (0.80±0.19) were lower than those in the control group ((0.63±0.23), (0.96±0.24))( t=2.08, 2.36, both P<0.05). Pearson correlation analysis showed that the Glu concentration in the left caudate nucleus of patients with obsessive-compulsive disorder was positively correlated with the total score of Y-BOCS( r=0.46, P<0.05). Spearman correlation analysis showed that Glu concentration in the right caudate nucleus was positively correlated with the total score of HAMA in patients with obsessive-compulsive disorder ( r=0.46, P<0.05). Conclusion:NAA, Glu and GABA metabolism in caudate nucleus and thalamus are abnormal in patients with obsessive-compulsive disorder, and Glu concentration is positively correlated with the severity of obsessive-compulsive and anxiety symptoms.
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Resumen: La definición de consciencia en sí encierra una gran dificultad por su esencia y la inmensa complejidad de los numerosos componentes y procesos que la conforman. La consciencia como característica inherente al ser humano ha sido objeto de numerosos estudios y tratados, no sólo científicos, sino además filosóficos, religiosos, éticos, etcétera. Esto también incluye la diferencia entre consciencia y conciencia. La dificultad para poder establecer el principio que da origen a la consciencia, representa, por lo tanto, un gran reto para poder dilucidar con certeza lo que sucede con ésta durante el evento anestésico. Gracias al entendimiento que se va logrando a través de las investigaciones concernientes a las funciones de diferentes y complejas estructuras, tales como la substancia activadora reticular ascendente, el tálamo, partes del cuerpo estriado y la corteza cerebral, entre otras, que se relacionan gracias a la existencia de redes neuronales, integradas a su vez por nodos con funciones específicas y a la vez variadas, capaces de intercomunicar estas estructuras encefálicas, aun estando distantes, se tiene ahora nociones sólidas de dónde, cómo y cuánto se puede ver afectada la integración de la consciencia como consecuencia del efecto de los diferentes anestésicos.
Abstract: To define consciousness per se, involves a great difficulty because of its essence and the huge complexity regarding the great number of its components and the processes within. Consciousness, as a human characteristic, has been matter of large researching not only through a scientific approach, but also from the perspective of philosophic, religious, ethics investigations among others, including the distinction between consciousness and awareness. The trouble to define the foundation of consciousness implies a great challenge to get to know, what is happening during the anesthesia period. Through the understanding that has been accomplished by way of investigations concerning the different and complex functions of diverse neural structures such as the brain stem reticular formation, the thalamus, some parts of the striatum and the cerebral cortex among others, how they become connected by the neuronal nets who are compounded by nodes that have not only specific but a wide array of functions, capable of interconnect all these encephalic structures, even though they are far away, we know now with a good amount of certainty, where, how and how much the integrity of consciousness can be affected as a consequence of the different anesthetics effect.
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Objective:To explore the changes of brain activity in drug-resistant or drug-controlled medial temporal lobe epilepsy patients by the method of functional connectivity density (FCD), and to analyze their correlation with the course of the disease.Methods:According to the definition of drug-resistant epilepsy by the International League Against Epilepsy in 2010, 146 patients with medial temporal lobe epilepsy who were clearly diagnosed as unilateral hippocampal sclerosis in Jinling Hospital, Nanjing University School of Medicine from July 2009 to February 2019 were divided into drug control group ( n=73) and drug-resistant group ( n=73). The 3.0 T resting state functional magnetic resonance scan was performed on all subjects to compare the difference in FCD between the two groups, and calculate the correlation between the FCD value of the brain area and the course of the disease between the two groups of patients. Results:There was significant difference between the two groups in FCD. Compared with the drug control group, the drug-resistant group had significantly lower FCD values in the insula, lenticular nucleus, thalamus, hippocampus and precentral gyrus on the side of the epileptogenic focus. The FCD value of the precuneus on the side of the epileptogenic focus in the drug-resistant group was negatively correlated with the duration ( r=-0.30, P=0.01). Conclusions:The FCD of patients with drug-resistant medial temporal lobe epilepsy was lower than that of the drug control group. In addition, there may be progressive damage to the brain. The difference is helpful for exploring the pathophysiological mechanisms related to drug resistance in patients with medial temporal lobe epilepsy, and finding reliable neuroimaging markers related to drug resistance.
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Objective:To explore the correlation and mechanism between thalamic network abnormality and cognitive decline in patients with temporal lobe epilepsy (TLE).Methods:A total of 53 patients with unilateral TLE were consecutively enrolled through the epilepsy clinic of the First Affiliated Hospital of Guangxi Medical University from December 2018 to February 2020. During the same recruitment interval, 37 health controls(HC) with matching demographic characteristic were recruited. All subjects were received the Montreal cognitive assessment(MoCA) test and multimodal MRI scanning. Voxel-based morphometry method was used to study the changes of thalamic gray matter volume in patients with unilateral TLE. The structural covariance network and functional connectivity network based on seed points were used to analyze the changes of thalamic network in TLE patients. In addition, the correlations among abnormal thalamic structure, thalamic network and cognitive function score were analyzed. SPSS 22.0 software was used for statistical analysis. Independent sample t-test and Mann Whitney U test were used for inter group comparison. In order to explore the relationship between thalamus and thalamic network and cognitive performance in TLE patients, thalamic volume and gray matter volume and functional connection value of brain areas with abnormal synergistic changes were extracted and correlated with MoCA score. Results:The total score of MoCA in TLE patients (27.0(25.0, 29.0)) was significantly decreased compared with HC (29.0(28.0, 30.0))( Z=-4.601, P<0.001). Whole brain gray matter volume analysis showed that compared with HCTLE patients showed significant volume reduction in left cerebellum, right temporal pole, right fusiform gyrus, straight gyrus, bilateral middle temporal gyrus, thalamus, medial and paracingulate gyrus (GRF adjusted, voxel-level P<0.001 and cluster-level P<0.05). The thalamus-associated structural covariance network analysis revealed that compared with healthy controls, TLE patients exhibited decreased connectivity in right fusiform gyrus (MNI: x=28.5, y=-15.0, z=-34.5), left insula (MNI: x=-33.0, y=-18.0, z=-1.5), right middle temporal gyrus (MNI: x=55.5, y=-51.0, z=9.0), left complementary motor area (MNI: x=-10.5, y=1.5, z=57.0) and right posterior central gyrus (MNI: x=31.5, y=-33.0, z=51.0) ( P<0.001, cluster > 100). The thalamus-associated functional connectivity network analysis revealed that TLE patients exhibited decreased connectivity in left insula (MNI: x=-38, y=-7, z=-7), left lingual gyrus (MNI: x=-6, y=-81, z=-12), right lingual gyrus (MNI: x=15, y=-105, z=0) and left triangular inferior frontal gyrus (MNI: x=-39, y=36, z=-6) (GRF correction, voxel-level P<0.001 and cluster-level P<0.05). Volume of left insula which had decreased structural connectivity with thalamus were positively correlated with the MoCA score in TLE patients( r=0.279, P=0.043). Volume of left complementary motor area which had decreased structural connectivity with thalamus was positively correalated with the MoCA score and language score in TLE patients( r=0.323, P=0.018; r=0.334, P=0.015). Volume of left lingual gyrus which had decreased functional connectivity with thalamus was negatively correalated with the memory score in TLE patients ( r=-0.331, P=0.016). Conclusion:Thalamic volume, thalamic structural covariant network and functional connection network are changed in TLE patients. The abnormality of thalamic network is associated with cognitive performance in TLE patients, which may be the neural mechanism of thalamus participating in the cognitive impairment of TLE patients.
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Objective:To evaluate the relationship between thalamocortical glutamate and neuronal activity in mice with neuropathic pain-induced sleep disorders.Methods:SPF healthy male C57BL/6 mice, aged 6-8 weeks, weighing 15-25 g, were divided into 2 groups ( n=14 each) using a random number table method: sham operation group (Sham group) and neuropathic pain group (CCI group). Neuropathic pain was induced by chronic constrictive injury (CCI). The animals were anesthetized with intraperitoneal 10% chloral hydrate 3 ml/kg.The right sciatic nerve was exposed and 4 ligatures were placed on the sciatic nerve at 1 mm intervals.The mechanical paw withdrawal threshold and thermal paw withdrawal latency on the operated side were measured at 1 day before CCI (T 0) and 3, 5, 7, 14 and 21 days after CCI (T 1-5). Electroencephalogram recording electrodes were stereotaxically implanted in visual cortex at T 3, and electroencephalogram were monitored for 6 h, the percentages of non-rapid eye movement, rapid eye movement and wakefulness in the total time were calculated.Microwire electrodes were implanted epidurally over the ventral posterior (VP) nucleus of the thalamus and primary somatosensory cortex (S1) using a brain stereotaxic apparatus at T 3, and the data acquisition system was used to record field potentials at T 4, the percentage of power of each wave was calculated, and the coherence of the field potentials of VP and S1 was simultaneously evaluated.The mice were sacrificed at T 4, brain tissues were collected, and proton nuclear magnetic resonance spectroscopy was used to determine the level of neurotransmitter in the thalamus and cortex. Results:Compared with group Sham, the mechanical paw withdrawal threshold was significantly decreased and thermal paw withdrawal latency was shortened at T 1-5, the percentage of non-rapid eye movement time was decreased, the percentage of wakefulness time was increased, the percentage of δ wave power in the VP area was decreased, the percentage of δ wave power in the VP and S1 areas was increased, and the coherence of the field potentials of VP-S1 was increased in the frequency range of δ wave (1-4 Hz) and α wave (8-14 Hz), and the levels of glutamate, glutamine and glutamate-glutamine in the thalamus and cortex were increased in group CCI ( P<0.05). Conclusions:Neuropathic pain-induced sleep disturbance is related to increased thalamocortical glutamate levels, resulting in changes in the electrical activity of thalamocortical neurons of mice.
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The deep cerebellar nuclei (DCN) integrate various inputs to the cerebellum and form the final cerebellar outputs critical for associative sensorimotor learning. However, the functional relevance of distinct neuronal subpopulations within the DCN remains poorly understood. Here, we examined a subpopulation of mouse DCN neurons whose axons specifically project to the ventromedial (Vm) thalamus (DCNVm neurons), and found that these neurons represent a specific subset of DCN units whose activity varies with trace eyeblink conditioning (tEBC), a classical associative sensorimotor learning task. Upon conditioning, the activity of DCNVm neurons signaled the performance of conditioned eyeblink responses (CRs). Optogenetic activation and inhibition of the DCNVm neurons in well-trained mice amplified and diminished the CRs, respectively. Chemogenetic manipulation of the DCNVm neurons had no effects on non-associative motor coordination. Furthermore, optogenetic activation of the DCNVm neurons caused rapid elevated firing activity in the cingulate cortex, a brain area critical for bridging the time gap between sensory stimuli and motor execution during tEBC. Together, our data highlights DCNVm neurons' function and delineates their kinematic parameters that modulate the strength of associative sensorimotor responses.
Subject(s)
Animals , Mice , Blinking , Cerebellar Nuclei/physiology , Cerebellum , Neurons/physiology , ThalamusABSTRACT
Abstract The diseases that affect the thalamus are heterogeneous in their etiologies, including infectious, inflammatory, vascular, toxic-metabolic, and neoplastic causes. It is often difficult to make the clinical differentiation between different entities. Within this context, computed tomography and magnetic resonance imaging have come to be of fundamental importance for defining the etiology and planning the treatment. In this pictorial essay, we will illustrate the main causes of diseases affecting the thalamus, discussing the possible differential diagnoses, as well as the most relevant imaging aspects.
Resumo As doenças que envolvem os tálamos incluem um grupo heterogêneo, englobando causas infecciosas, inflamatórias, vasculares, tóxico-metabólicas e neoplásicas. Muitas vezes a diferenciação clínica entre as diversas entidades é difícil, e dentro desse contexto, a tomografia computadorizada e a ressonância magnética assumiram fundamental importância na busca da definição etiológica e para guiar a conduta terapêutica. Neste ensaio iconográfico ilustraremos as principais causas de acometimento talâmico, discutindo seus possíveis diagnósticos diferenciais, bem como seus aspectos de imagem mais relevantes.
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RESUMEN La hemorragia talámica pertenece al grupo de las hemorragias intracerebrales de etiología no traumática o quirúrgica. Es una entidad relativamente infrecuente y tiene una prevalencia de 6-15 % de los casos dentro de dicho grupo. El tálamo es una estructura anatómica donde convergen múltiples vías neuronales, por lo tanto, sus manifestaciones clínicas no están totalmente descritas. A pesar de ello, se conoce que su presentación clínica más frecuente está asociada al síndrome sensitivo de Déjerine-Roussy, caracterizado por intenso dolor neuropático, alodinia contralateral a la lesión, hemiparesia y hemiataxia. La hemorragia talámica también se puede presentar con alteraciones de la memoria, sueño, emociones y procesamiento de información sensitiva. Se presenta un caso de hemorragia talámica izquierda espontánea en un paciente de 71 años que debutó con cambios en su comportamiento, bradipsiquia y amnesia anterógrada, con posterior recuperación completa de su estado cognitivo y psicológico antes de los 8 días y con hallazgos normales en la panangiografía.
ABSTRACT Thalamic hemorrhage belongs to the group of intracerebral hemorrhages of non-traumatic or surgical etiology. It is relatively rare and has a prevalence of 6-15% of cases. The thalamus is an anatomical structure where multiple neural pathways converge; therefore, its clinical manifestations are not fully described. Despite this, it is known that its most frequent clinical presentation is associated with the Dejerine-Roussy sensory syndrome, characterized by intense neuropathic pain, allodynia contralateral to the lesion, hemiparesis and hemiataxia. Thalamic hemorrhage can also present with alterations in memory, sleep, emotions, and the processing of sensitive information. We present a case of spontaneous left thalamic hemorrhage in a 71-year-old patient who presented with changes in his behavior, bradypsy-chia, and anterograde amnesia, with subsequent complete recovery of his cognitive and psychological state before 8 days and with normal findings in the panangiography.
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The paraventricular nucleus of the thalamus (PVT), which serves as a hub, receives dense projections from the medial prefrontal cortex (mPFC) and projects to the lateral division of central amygdala (CeL). The infralimbic (IL) cortex plays a crucial role in encoding and recalling fear extinction memory. Here, we found that neurons in the PVT and IL were strongly activated during fear extinction retrieval. Silencing PVT neurons inhibited extinction retrieval at recent time point (24 h after extinction), while activating them promoted extinction retrieval at remote time point (7 d after extinction), suggesting a critical role of the PVT in extinction retrieval. In the mPFC-PVT circuit, projections from IL rather than prelimbic cortex to the PVT were dominant, and disrupting the IL-PVT projection suppressed extinction retrieval. Moreover, the axons of PVT neurons preferentially projected to the CeL. Silencing the PVT-CeL circuit also suppressed extinction retrieval. Together, our findings reveal a new neural circuit for fear extinction retrieval outside the classical IL-amygdala circuit.
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The cerebellum is conceptualized as a processor of complex movements and is also endowed with roles in cognitive and emotional behaviors. Although the axons of deep cerebellar nuclei are known to project to primary thalamic nuclei, macroscopic investigation of the characteristics of these projections, such as the spatial distribution of recipient zones, is lacking. Here, we studied the output of the cerebellar interposed nucleus (IpN) to the ventrolateral (VL) and centrolateral (CL) thalamic nuclei using electrophysiological recording in vivo and trans-synaptic viral tracing. We found that IpN stimulation induced mono-synaptic evoked potentials (EPs) in the VL but not the CL region. Furthermore, both the EPs induced by the IpN and the innervation of IpN projections displayed substantial heterogeneity across the VL region in three-dimensional space. These findings indicate that the recipient zones of IpN inputs vary between and within thalamic nuclei and may differentially control thalamo-cortical networks.
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Objective:To analyze the clinical presentation, potential pathogenesis, diagnosis, management and prognosis of dural arteriovenous fistula (DAVF) manifesting as bithalamic lesions.Methods:The clinical data of three patients with DAVF manifesting as bithalamic lesions from the First Affiliated Hospital of Xi'an Jiaotong University between August 2019 and August 2020 were analyzed retrospectively, and related literatures were reviewed.Results:Patient 1, a 56-year-old female, presented with a one-month aggressive clinical course of weakness, somnolence, nausea, vomiting, urine incontinence and sitting instability. Patient 2, a 53-year-old male, presented with a one-month aggressive clinical course of disturbance of consciousness, walking with difficulty and decreased higher cortex function. Patient 3, a 68-year-old male, presented with an eight-day aggressive clinical course of memory loss, disturbance of consciousness and mental symptoms. In these three patients, cranial computed tomography (CT) scans showed bilateral hypodensity shadow in thalamus while magnetic resonance imaging (MRI) demonstrated bithalamic edema. Magnetic resonance angiography (MRA) or computed tomography angiography (CTA) presented venous or venous sinus closely related with arteries. Digital substraction angiography (DSA) of the patient 1 demonstrated bilateral occipital artery-straight sinus DAVF treated with surgical excision. Four months later, the patient was consciousness with modified Rankin scale (mRS) score of 5. DSA of the patient 2 demonstrated DAVF supplied by the right external carotid artery and the symptoms were relieved after endovascular embolization. One year after operation, there was no recurrence and mRS score was 2. DSA of the patient 3 demonstrated occipital sinusional area DAVF treated with surgical excision. More than one year after surgery, the patient was conscious with mRS score of 5.Conclusions:DAVF-induced bithalamic lesions is a rare disorder in which clinical presentations are not specific.When cranial CT or MRI demonstrating bithalamic lesions, MRA or CTA showing venous or venous sinus closely related with arteries or presenting with disturbance of consciousness or cognitive decline, DAVF should be considered. DSA is the gold standard for diagnosis of DAVF. Endovascular embolization and surgical excision are the main treatments of DAVF.
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Thalamus plays an important role in the connection of sensory, motor and cognitive functions between multiple subcortical regions and cerebral cortex. In recent years, the important role of thalamus in cognitive function has attracted more and more attention. This article reviews the related research progress of thalamic infarction and cognitive impairment.
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Objective:To evaluate the effect of remimazolam pretreatment on brain injury following thalamic hemorrhage in mice.Methods:Sixty clean-grade healthy adult CD1 male mice, weighing 25-30 g, aged 7-8 weeks, were divided into 3 groups ( n=20 each) by using a random number table method: sham operation group (Sham group), brain injury group (BI group) and remimazolam pretreatment group (Rem group). Remimazolam 25 mg/kg was intravenously injected via the tail vein in group Rem.and the equal volume of normal saline was given instead in Sham group and BI group.Ten min later, type Ⅳ collagenase 0.01 U/10 nl was microinjected into unilateral ventroposterolateral nucleus and ventromedial nucleus to develop a mouse model of brain jury induced by thalamic hemorrhage.The rats were sacrificed at 6 h after developing the model, brain tissues were taken for measurement of the wet/dry weight (W/D) ratio, and hippocampal tissues were taken and stained with haematoxylin and eosin for determination of the count of the viable neurons in the hippocampal dentategyrus area, count of apoptotic neurons in the hippocampal CA1 region (by TUNEL), expression of CCAAT/enhancer-binding protein homologous protein (CHOP), activating transcription factor 4 (ATF4) and X-box binding protein-1 (XBP1) mRNA (by real-time polymerase chain reaction) and expression of CHOP, Bcl-2, Bax and caspase-3 (by Western blot) and for microscopic examination of ultrastructure of hippocampal tissues (with a transmission electron microscope). Results:Compared with group Sham, the W/D ratio of brain tissues and count of apoptotic neurons in the hippocampal CA1 area were significantly increased, the count of viable neurons in the hippocampal dentate gyrus was decreased, the expression of CHOP, ATF4 and XBP1 mRNA in hippocampal tissues was up-regulated, the expression of CHOP, caspase-3 and Bcl-2 was up-regulated, and the expression of Bax was down-regulated in BI and Rem groups ( P<0.05). Compared with group BI, the W/D ratio of brain tissues and count of apoptotic neurons in the hippocampal CA1 area were significantly decreased, the number of viable neurons in the hippocampal dentate gyrus was increased, the expression of CHOP, ATF4 and XBP1 mRNA in hippocampal tissues was down-regulated, the expression of CHOP, caspase-3 and Bcl-2 was down-regulated, and the expression of Bax was up-regulated in group Rem ( P<0.05). Conclusion:Remimazolam pretreatment can reduce the brain injury following thalamic hemorrhage in mice, and the mechanism may be related to inhibition of cell apoptosis induced by endoplasmic reticulum stress in hippocampus.
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The cerebellum is conceptualized as a processor of complex movements and is also endowed with roles in cognitive and emotional behaviors. Although the axons of deep cerebellar nuclei are known to project to primary thalamic nuclei, macroscopic investigation of the characteristics of these projections, such as the spatial distribution of recipient zones, is lacking. Here, we studied the output of the cerebellar interposed nucleus (IpN) to the ventrolateral (VL) and centrolateral (CL) thalamic nuclei using electrophysiological recording in vivo and trans-synaptic viral tracing. We found that IpN stimulation induced mono-synaptic evoked potentials (EPs) in the VL but not the CL region. Furthermore, both the EPs induced by the IpN and the innervation of IpN projections displayed substantial heterogeneity across the VL region in three-dimensional space. These findings indicate that the recipient zones of IpN inputs vary between and within thalamic nuclei and may differentially control thalamo-cortical networks.
Subject(s)
Axons , Cerebellar Nuclei , Cerebellum , Thalamic NucleiABSTRACT
OBJECTIVES@#To study the changes in biochemical metabolites in the thalamus and the cerebellum and their association with clinical features in children with autism spectrum disorder (ASD).@*METHODS@#In this prospective study, magnetic resonance spectroscopy (MRS) with point-resolved spatial selection was used to analyze the thalamus and the cerebellum at both sides in 50 children with ASD aged 2-6 years. Creatine (Cr) was as the internal standard to measure the relative values of N-acetylaspartate (NAA)/Cr, choline (Cho)/Cr, myoinositol (MI)/Cr, and glutamine and glutamate complex (Glx)/Cr, and the differences in metabolites and their association with clinical symptoms were compared.@*RESULTS@#In the children with ASD, NAA/Cr in the left thalamus was positively correlated with the scores of hearing-language and hand-eye coordination in the Griffiths Development Scales-Chinese (@*CONCLUSIONS@#There are metabolic disorders in the cerebellum and the thalamus in children with ASD, and there is a correlation between the changes of metabolites in the left cerebellum and the left thalamus. Some metabolic indexes are related to the clinical symptoms of ASD. MRS may reveal the pathological basis of ASD and provide a basis for diagnosis and prognosis assessment of ASD as a noninvasive and quantitative detection method.
Subject(s)
Child , Humans , Autism Spectrum Disorder/diagnostic imaging , Cerebellum/diagnostic imaging , Choline , Magnetic Resonance Spectroscopy , Prospective Studies , Thalamus/diagnostic imagingABSTRACT
O infarto da artéria de Percheron é uma apresentação rara de acidente vascular cerebral, caracterizado principalmente por isquemia talâmica bilateral. A apresentação clinica desse infarto se apresenta de maneira inesperada e variável. Relata-se um caso de um paciente masculino, idoso, acometido por diversas comorbidades, admitido na emergência em coma e hemiplégico a direita, demonstrando acometimento neurológico. A condição clínica do paciente variou durante a hospitalização, apresentando melhora do quadro neurológico focal e midríase fixa à direita, levando a um diagnóstico tardio. Paciente evoluiu ao óbito devido a causas não neurológicas.
The artery of Percheron infarct is a rare presentation of stroke, featured mainly by thalamic bilateral ischemia. The clinical presentation of this infarct is unexpected and variable. It's reported a case of a male patient, elderly, affected with several comorbidities, admitted to the emergency in comatose state and right hemiplegic, proving neurological involvement. The patient's clinical condition has fluctuated throughout the hospitalization presenting improvement of the focal neurologic implication and right mydriasis, culminating in a lagged diagnosis. Patient's death due to non neurologic causes.