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Objective Methods Results Significance Loss‐of‐function mutations in the GIRDIN/CCDC88A gene cause developmental epileptic encephalopathy (DEE) in humans. However, its pathogenesis is largely unknown. Global knockout mice of the corresponding orthologous gene (gKOs) have a preweaning lethal phenotype with growth failure, preventing longitudinal analysis. We aimed to overcome this lethality and elucidate DEE pathogenesis.We developed a novel lifelong feeding regimen (NLFR), which consists of providing mash food from postnatal day 14 (P14) until weaning (P28), followed by agar‐bound food exclusively after weaning. Videography, electroencephalography (EEG), and histological analyses were performed. Conditional Girdin/Ccdc88a knockout mice (cKOs) of variable lineages (Nestin, Emx1, or Nkx2‐1) were generated to identify the region responsible for epilepsy.Under the NLFR, gKOs survived beyond 1 year and displayed fully penetrant, robust epileptic phenotypes, including early‐onset (P22.3 in average) generalized tonic–clonic seizures (GTCSs) (averaging eight per day), which were completely synchronized with fast rhythms on EEG, frequent interictal electroencephalographic spikes (averaging 430 per hour), and progressive deformation of visceral organs. In addition, gKOs had absence seizures, which were not always time‐locked to frequent spike waves on EEG. The frequent GTCSs and interictal spikes in gKOs were suppressed by known antiepileptic drugs. Histologically, bilateral hippocampi in gKOs exhibited congenital cornu‐ammonis splitting, granule cell dispersion, and astrogliosis. Furthermore, analysis of conditional knockouts using multiple Cre‐deleters identified a defect in the delivery of interneuron precursors from the medial ganglionic eminence into the hippocampal primordium during embryogenesis as a major cause of epileptogenesis.These findings give rise to a new approach of lifelong caregiving to overcome the problem of preweaning lethality in animal models. We propose a useful model for studying DEE with hippocampal sclerosis and interneuronopathy. gKOs with NLFR combine the contradictory properties of robust epileptic phenotypes and long‐term survivability, which can be used to investigate spontaneous epileptic wave propagation and therapeutic intervention in hippocampal sclerosis. [ABSTRACT FROM AUTHOR]

Solitary fibrous tumors (SFTs) are rare mesenchymal cell‐derived tumors that can cause substantial bleeding during surgery due to hyper‐vascularization. We report a case of a large retroperitoneal SFT resected completely using an intra‐aortic balloon. A 71‐year‐old female with a history of type 2 diabetes mellitus presented with a tumor that was diagnosed as an insulin‐like growth factor‐II‐producing benign SFT using computed tomography‐guided biopsy. The tumor had grown from 6 to 20 cm in diameter within 4 years, with concurrent and severe hypoglycemia. Preoperative computed tomography findings showed substantial blood flow toward the tumor. The retroperitoneal tumor was observed to be widely attached. Substantial hemorrhaging during tumor resection was observed despite vascular embolism. We inflated the intra‐aortic balloon for 45 min and resected the tumor completely. In conclusion, large SFT resection requires preoperative tumor blood flow evaluation and preparation of both a vascular embolism and an intra‐aortic balloon. [ABSTRACT FROM AUTHOR]

Abstract: Neuronal intrinsic homeostatic scaling‐down of excitatory synapse has been implicated in epilepsy pathogenesis to prevent the neuronal circuits from hyperexcitability. Recent findings suggest a role for neuronal PAS domain protein 4 (Npas4), an activity‐dependent neuron‐specific transcription factor in epileptogenesis, however, the underlying mechanism by which Npas4 regulates epilepsy remains unclear. We herein propose that limbic seizure activity up‐regulates Npas4‐homer1a signaling in the hippocampus, thereby contributing to epileptogenesis in mice. The expression level of Npas4mRNA was significantly increased after the pentylenetetrazol (PTZ) treatment. Npas4KO mice developed kindling more rapidly than their wild‐type littermates. The expression of Homer1a in the hippocampus increased after seizure activity. Npas4 increased Homer1a promoter activity in COS7 cells. The PTZ‐stimulated induction of Homer1a was attenuated in the hippocampus of Npas4KO mice. The combination of fluorescence in situ hybridization and immunohistochemical analyses revealed that Homer1amRNA co‐localized with the Npas4 protein after the convulsive seizure response. PTZ reduced excitatory synaptic transmission at the associational/commissural fibers‐CA3 synapses through the Npas4‐mediated down‐regulation of postsynaptic α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid receptors in hippocampal CA3 neurons. The adeno‐associated virus (AAV)‐mediated expression of Homer1a resulted in lower α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid‐type glutamate receptor GluA1 subunit levels in the hippocampal plasma membrane fraction than in that from AAV‐EGFP‐transfected Npas4KO mice. The development of kindling was more strongly suppressed in AAV‐Homer1a‐microinjected Npas4KO mice than in AAV‐EGFP‐microinjected Npas4KO mice. These results indicate that Npas4 functions as a molecular switch to initiate homeostatic scaling and the targeting of Npas4‐Homer1a signaling may provide new approaches for the treatment of epilepsy. [ABSTRACT FROM AUTHOR]

Here, we report a case of traumatic pulmonary pseudocysts (TPPs) coinciding with vertebral fracture. Traumatic pulmonary pseudocysts (TPPs) are rare complications of blunt chest trauma. These clinical images of CT, presenting here, seemed to be valuable because they show the process of pseudocyst formation. [ABSTRACT FROM AUTHOR]

The neurosteroid dehydroepiandrosterone-sulfate (DHEAS) is a positive modulator of synaptic transmission in mammalian brains; however, the underlying molecular mechanisms are not fully understood. This report describes the acute effects of DHEAS on the synaptic transmission in the hippocampal dentate gyrus of rat brain slices. The application of DHEAS for 10 min augmented the optically recorded EPSP (op-EPSP) in a dose dependent manner. The effect became visible at 1 nM and saturated at 100 nM. We focused on the effect of DHEAS at 100 nM, where the op-EPSP amplitude was increased by 30%, and gradually decreased to the basal level in 30 min after wash out of the drug (short-term potentiation by DHEAS; STPDHEAS). DHEAS did not alter the presynaptic properties including the presynaptic fiber volley (PSFV) and paired pulse facilitation (PPF), thus indicating that the acute DHEAS effect is of postsynaptic origin. The involvement of putative DHEAS targets, GABAA, NMDA, and σ1 receptors in STPDHEAS was also investigated; however, antagonists to these receptors only partially inhibited the acute effect of DHEAS. By contrast, STPDHEAS was totally inhibited by either the metabotropic glutamate receptor 5 (mGluR5) antagonist MPEP (10 μM) or the ryanodine receptor (RyR) inhibitors (ryanodine and ruthenium red), but not by the mGluR1 antagonist LY367385 and the IP3R antagonist 2-APB, suggesting that STPDHEAS is mediated by an mGluR5-RyR cascade in postsynaptic neurons. Consistent with this finding, the selective agonist for mGluR5 CHPG nearly perfectly mimicked the DHEAS effect. This is the first demonstration of mGluR involvement in the DHEAS action in regard to hippocampal synaptic transmission. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]