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11.
Epilepsy is an important problem in neurological disorders. The common features of all types of epilepsy are the synchronized and uncontrolled discharges of nerve cell assemblies. Recent studies claimed that gap junctions have a critical role in epileptic neuronal events. The aim of present study is to investigate the effects of connexin36 (Cx36) channel blocker quinine on penicillin-induced experimental epilepsy. For this purpose, 4 months old male Wistar rats were used in the present study. Permanent screw electrodes allowing EEG monitoring from conscious animals and permanent cannula providing the administration of the substances to the brain ventricle were placed into the cranium of rats under general anesthesia. At the end of the postoperative recovery period, epileptiform activity was generated by injecting 300 IU crystallized penicillin through the ventricular cannula. When the epileptiform activity, monitored from a digital recording system, reached maximal frequency and amplitude, quinine (200, 400 or 1000 nmol) was administered similar to penicillin. Effects of quinine on epileptiform activity were assessed by both electrophysiological and behavioral analysis. Quinine suppressed epileptiform activity by decreasing the amplitude and frequency of epileptiform spikes and by attenuating the epileptiform behavior. The outcomes of this study suggest that the blockade of Cx36 channels may contribute to the amelioration of epileptic activity.  相似文献   
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13.
Fifteen parameters that play a role in the optimal transmission of therapeutic signals by inductively coupled implantable neurostimulator have been investigated. For this purpose, at first, a model of the system was constructed from which the system transfer function was obtained. Then, the relationship between the transfer gain and each parameter was evaluated using mathematical equations and a specifically built computer program. This study showed that the gain could be increased selecting small values for some parameters (the number of active coil windings, first radii of inner and outer paths of the core, heights of the core base and windings, position under the skin, internal resistances of the active and passive coils, tissue impedance between the contacts of electrode), and high values for the others (the number of passive coil windings, second radii of inner and outer paths of the core, frequency of the signal, relative magnetic permeability of the core). Critical saturation values were another considerable point. The nearest commercially available standard values should be preferred in practical applications.  相似文献   
14.
The influence of diet on the development of osteoporosis is significant and not fully understood. This study investigated the effect of diets of varying lipid profiles and ω-3, ω-6 and ω-9 composition on the structural and mechanical properties of bone. The hypothesis studied was that a diet high in saturated fat would induce osteoporosis and produce an overall increased detrimental bony response when compared with a diet high in unsaturated ω-6, or ω-9. Male C57BL/6J mice were fed either a control diet, 50:50 mix (saturated:unsaturated) high in ω-9 (HFD50:50), a diet high in saturated fat (HSF) or a polyunsaturated fat diet high in ω-6 (PUFA) over an 8-week duration. Tibiae were retrieved and evaluated using DMA, 3-point-bending, histomorphometry, and microCT. Mice fed a HSF diet displayed key features characteristic of osteoporosis. The loss tangent was significantly increased in the HFD50:50 diet group compared with control (p = 0.016) and PUFA-fed animals (p = 0.049). HFD50:50-fed mice presented with an increased viscous component, longer tibiae, increased loss modulus (p = 0.009), and ultimate stress, smaller microcracks (p < 0.001), and increased trabecular width (p = 0.002) compared with control animals. A diet high in ω-9 resulted in an overall superior bone response and further analysis of its role in bone health is warranted.  相似文献   
15.
Photoacoustic imaging is a promising new technology that combines tissue optical characteristics with ultrasound transmission and can potentially visualize tumor depth in bladder cancer. We imaged simulated tumors in 5 fresh porcine bladders with conventional pulse‐echo sonography and photoacoustic imaging. Isoechoic biomaterials of different optical qualities were used. In all 5 of the bladder specimens, photoacoustic imaging showed injected biomaterials, containing varying degrees of pigment, better than control pulse‐echo sonography. Photoacoustic imaging may be complementary to diagnostic information obtained by cystoscopy and urine cytologic analysis and could potentially obviate the need for biopsy in some tumors before definitive treatment.  相似文献   
16.
Blau syndrome is a rare, multisystem, autosomal-dominant, and granulomatous disorder caused by susceptibility variants in the NOD2 gene. We describe here a 14-year-old girl with Blau syndrome with incidentally diagnosed renal carcinoma. The index case presented with growth retardation and recurrent symmetric arthritis. Her clinical symptoms included bilateral cataract due to recurrent uveitis, camptodactyly, and persistent erythematous rash with ichthyosis. Her two sisters and her mother were affected with combinations of these conditions—symmetric polyarthritis, uveitis, and skin involvement—suggesting an autosomal dominant trait. The index case developed a chronic renal insufficiency, and an abdominal computerized tomography scan revealed a 2.5-cm mass in the left kidney. The histopathological examination showed renal clear cell carcinoma, chronic tubulointerstitial nephritis, and giant cell granulomas in both the tumor and non-neoplastic renal tissue. Granulomatous inflammation was observed in the skin biopsy specimen. The patient was diagnosed with Blau syndrome based on her family history, uveitis, granulomatous inflammation proved by skin biopsy, and polyarthritis. Sequencing of the NOD2 gene showed a heterozygous p.R334Q mutation in all affected family members. To the best of our knowledge, this is the first reported case of a patient with Blau syndrome accompanied by chronic renal failure and renal carcinoma.  相似文献   
17.
This study investigated the effect of rifampin on the thickness of capsules around silicone implants by bactericidal activity against Stapylococcus epidermidis. Silicone blocks (1 × 1 cm) were placed into pockets created for each of the 40 rats included in the study. In group 1, the operation was performed under aseptic conditions. In group 2, standard S. epidermidis was inoculated into the pocket, whereas rifampin and S. epidermidis were applied in group 3. In group 4, only rifampin was applied topically on implants. After 12 weeks, the peri-implant capsules were removed and examined under a photomicroscope and a scanning electron microscope. The mean thickness of the capsules was 63.307 μm in group 1, 111.538 μm in group 2, 43.076 μm in group 3, and 30.384 μm in group 4. The differences between groups 2 and 3 and groups 2 and 4 were found to be statistically significant (p < 0.001). Rifampin appears to be an agent for preventing peri-implant capsule formation.  相似文献   
18.
The morphological features of centrotemporal spike discharges (CTSD) and relationship of them with clinical diagnosis in cases with benign epilepsy of childhood with centrotemporal spikes (BECTS) and the other epileptic syndromes of childhood as well as some nonconvulsive neurological disorders were detected in the routine patient population who referred to the authors' EEG laboratory. Thirty-six cases (21 males, 15 females; 8 months-14 years old), in which awake and/or sleep EEGs revealed CTSD were included in this study. The cases were divided into two groups as epileptic and nonepileptic. The cases with seizure were divided into BECTS and the other epilepsies. Of the epileptic cases, 14 (38.8%) patients had typical rolandic seizures. In five cases, there were partial or secondary generalized seizures. Two cases had myoclonic seizures. In the nonepileptic group, there was mental retardation/behavioral disturbances in five cases; there were periodic syndromes of childhood such as migraine and equivalents of migraine in three cases; febrile convulsion in three cases, breath-holding spells in two cases, and primary enuresis nocturna in two cases. In the nonepileptic group, the discharges were significantly fewer than the other groups (p = .014). More frequent discharges occuring for shorter periods were more significantly observed in BECTS group (64%). Typically isolated spike and slow-waves in T3/T4 and C3/C4 location were significantly more common (86%) in rolandic epilepsy group (p = .01). The EEGs of cases with BECTS had more frequency in the cluster of discharges than the other groups (p = .018). Multifocal discharges were observed in 28.5% of cases with BECTS, in 20% of nonepileptic group, and in 71.4% of other epileptics in the trial. Although these epileptic and nonepileptic conditions have some differences in view of frequency and morphology and location, CTSDs could be manifested in the group without seizure. It was concluded that the similar focal abnormalities which could be seen in rolandic epilepsy may be observed in the other epileptic or nonepileptic disorders of childhood and this condition may be originated from the involvement of similar central structures.  相似文献   
19.
Primary pulmonary artery leiomyosarcoma is a rare tumor that can be misdiagnosed as acute or chronic pulmonary thromboembolic disease. In this report, we present a case of a 58-year-old woman initially diagnosed with chronic thromboembolic pulmonary disease, but who was later found to have pulmonary artery leiomyosarcoma. A complete mass resection was performed surgically. The definitive pathologic examination was consistent with pulmonary artery leiomyosarcoma. Although the patient did not receive adjuvant therapy after the surgery, she had a good outcome and was free of disease 8 months after surgery.  相似文献   
20.
Since the first published report of a fenestrated endovascular aneurysm repair, we have seen an expansion in the range of custom-made devices used to manage complex aortic aneurysms. Fenestrated devices, branched devices, and chimneys are now frequently used in many centers to repair these aneurysms. Similar to standard endovascular aneurysm repair, the advantages of less operative blood loss, decreased hospital stay, and reduced risk of morbidity and mortality hold true for endovascular repair of complex aneurysms as well. This is contrasted by the requirement for long-term surveillance and increased incidence of secondary interventions.  相似文献   
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