Background: Preconditioning the brain with relatively safe drugs seems to be a viable option to reduce ischemic brain injury. The authors and others have shown that the volatile anesthetic isoflurane can precondition the brain against ischemia. Here, the authors determine whether isoflurane preconditioning improves long-term neurologic outcome after brain ischemia.
Methods: Six-day-old rats were exposed to 1.5% isoflurane for 30 min at 24 h before the brain hypoxia-ischemia that was induced by left common carotid arterial ligation and then exposure to 8% oxygen for 2 h. The neuropathology, motor coordination, and learning and memory functions were assayed 1 month after the brain ischemia. Western analysis was performed to quantify the expression of the heat shock protein 70, Bcl-2, and survivin 24 h after isoflurane exposure.
Results: The mortality was 45% after brain hypoxia-ischemia. Isoflurane preconditioning did not affect this mortality. However, isoflurane preconditioning attenuated ischemia-induced loss of neurons and brain tissues, such as cerebral cortex and hippocampus in the survivors. Isoflurane also improved the motor coordination of rats at 1 month after ischemia. The learning and memory functions as measured by performance of Y-maze and social recognition tasks in the survivors were not affected by the brain hypoxia-ischemia or isoflurane preconditioning. The expression of Bcl-2, a well-known antiapoptotic protein, in the hippocampus is increased after isoflurane exposure. This increase was reduced by the inhibitors of inducible nitric oxide synthase. Inducible nitric oxide synthase inhibition also abolished isoflurane preconditioning-induced neuroprotection. 相似文献
BACKGROUND: The renal dynamic imaging method (modified Gate's method) with (99m)Tc-diethylene triamine pentaacetic acid ((99m)Tc-DTPA) is simple and less time consuming for glomerular filtration rate (GFR) estimation than other methods. However, its diagnostic performance as a surrogate marker of GFR is questioned increasingly. Recently, the modified Modification of Diet in Renal Disease (MDRD) study equation based on data from Chinese patients of chronic kidney disease (CKD) showed significant performance improvement. In the present study, the renal dynamic imaging methods and the modified abbreviated MDRD equation were compared with the plasma clearance method. METHODS: Four hundred and eighty two patients with CKD were selected. GFR were estimated simultaneously using three methods: (i) modified Gate's method (gGFR); (ii) the modified abbreviated MDRD equation (c-aGFR) and (iii) dual plasma sampling method (rGFR). Using rGFR as the reference method, gGFR and c-aGFR were compared with rGFR in each stage of CKD. RESULTS: Both gGFR and c-aGFR were correlated well with rGFR (r(gGFR) = 0.81 and r(c-aGFR) = 0.90, P < 0.001). In the overall performance, c-aGFR had less bias (849.5 vs 933.1 arbitrary units), higher precision (57 vs 78.4 ml/min/1.73 m(2)) and higher accuracy than gGFR. For gGFR, the 15, 30 and 50% accuracies were 32.4, 56.0 and 79.1%, respectively; for c-aGFR, the corresponding accuracy rose to 43.2%, 75.5% and 90.9%, respectively. In each stage of CKD, the modified abbreviated MDRD equation also outperformed the modified Gate's method in the GFR estimation. CONCLUSION: Our results indicated that the performance of the renal dynamic imaging in total GFR estimation was not better than the modified abbreviated MDRD equation in our patient group, and should not be used as a surrogate marker of GFR, especially in clinical trials. We presume that the dynamic renal imaging methods for estimation of GFR can be improved by using proper reference GFR, more adequate background subtraction and soft-tissue attenuation correction, in a relatively larger sample size. 相似文献
Tumor-related hemifacial spasm (HFS) has been found to be rare. During the period from October 1984 to October 2008, we treated
6,910 HFS patients using a microsurgical procedure. Of these HFS patients, 55 cases were associated with cerebellopontine
angle tumors. A small craniectomy was performed in order to excise the tumor. All tumors were found to compress the root exit
zone (REZ) of the facial nerve to different extents, but concomitant vascular compression of the facial nerve was observed
in a majority of cases, and microvascular decompression of the facial nerve at REZ was conducted in 43 of 55 patients (78.2%)
by displacing the co-compressing vasculature away from the REZ and retaining it using a Teflon pad. Intraoperative findings
and postoperative pathological examinations suggested that the tumors were epidermoid cysts, meningiomas, and Schwannomas.
Follow-up in 48 of 55 patients for 4–230 months after surgery showed that the clinical symptoms of HFS disappeared in 43 cases,
improved in two cases, and recurred in three cases. Ten patients had sequelae associated with the operation. We concluded
from this study that the majority of cases of tumor-related HFS are caused by combined tumor and vascular co-compression at
the REZ, and tumor removal and microvascular decompression are required in order to relieve the symptoms. 相似文献
Abstract: Dermatofibrosarcoma protuberans (DFSP) is a rare superficial soft tissue malignancy. We report a 45‐year‐old woman diagnosed with DFSP involving the breast. Ultrasound of DFSP revealed a heteroechogenetic breast mass, which showed normal adjacent dermis. Mammography disclosed a high‐density mass without microcalcification. MRI showed an enhancing lobulated lesion with small area of cystic change and hemorrhage. The patient underwent excision biopsy and pathology revealed DFSP of the breast. DFSP involving the breast is rare and preoperative diagnosis by imaging could be a challenge for clinicians. A solitary mixed echogenicity and ill‐defined soft tissue with no microcalcification located in the subdermal region could indicate the presence of DFSP. 相似文献