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21.

Purpose

Intracranial aneurysms in children are not as common as in adults and there are many differences in the etiology, demographic variables, aneurysm location, aneurysm morphological characteristics, clinical presentation, and outcome in pediatric and adult intracranial aneurysms.

Methods

All children (≤18 years) suffering from intracranial aneurysm managed at our center from July 2001 through June 2013 were included in the study, and the details of these patients were retrieved from the computerized database of our hospital.

Observations

A total of 62 pediatric patients were treated for 74 aneurysms during the study period and constituted 2.3 % of all intracranial aneurysms treated during the same period. The mean age at presentation was 13.5 years. Headache (82 %) was the commonest presenting feature; other symptoms included seizures (21 %), ictal loss of consciousness (27 %), and motor/cranial nerve deficits (22.6 %). Computed tomogram revealed subarachnoid hemorrhage in 58 % of patients. Eighty-two percent of aneurysms were in anterior circulation. Sixty-seven percent of aneurysms were complex aneurysms. Fifty-eight percent of patients underwent surgical intervention while 30 % underwent endovascular procedures. Twenty-one percent of the patients developed vasospasm. There was no postoperative mortality. Favorable outcome was seen in 72 % of the patients.

Conclusions

Pediatric intracranial aneurysms are uncommon as compared to in adult patients. Seizures and cranial nerve involvement are seen more often as the presenting features in children. Posterior circulation aneurysms are more common in children, as are the internal carotid artery bifurcation aneurysms. There is high incidence of giant, posttraumatic, and mycotic aneurysms in children.  相似文献   
22.
We report three cases of spinal angiolipoma, two intramedullary and one epidural, and review their MRI features. Diagnoses were established preoperatively in all cases. Specific MRI features including the importance of postgadolinium fat-saturated T1-weighted images and presence of vascular flow-voids are discussed with histopathological correlation. A characteristic morphological appearance of intramedullary angiolipoma has been suggested.  相似文献   
23.

Background  

We previously identified brain type fatty acid-binding protein (FABP7) as a prognostic marker for patients with glioblastoma (GBM). Increased expression of FABP7 is associated with reduced survival. To investigate possible molecular mechanisms underlying this association, we compared the expression and subcellular localization of FABP7 in non-tumor brain tissues with different types of glioma, and examined the expression of FABP7 and epidermal growth factor receptor (EGFR) in GBM tumors.  相似文献   
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The release of mitochondrial cytochrome c by genotoxic stress induces the formation of a cytosolic complex with Apaf-1 (mammalian CED4 homolog) and thereby the activation of procaspase-3 (cas-3) and procaspase-9 (cas-9). Here we demonstrate that heat-shock protein 27 (Hsp27) inhibits cytochrome c (cyt c)-dependent activation of cas-3. Hsp27 had no effect on cyt c release, Apaf-1 and cas-9 activation. By contrast, our results show that Hsp27 associates with cas-3, but not Apaf-1 or cas-9, and inhibits activation of cas-3 by cas-9-mediated proteolysis. Furthermore, the present results demonstrate that immunodepletion of Hsp27 depletes cas-3. Importantly, treatment of cells with DNA damaging agents dissociates the Hsp27/cas-3 complex and relieves inhibition of cas-3 activation. These findings define a novel function for Hsp27 and provide the first evidence that a heat shock protein represses cas-3 activation.  相似文献   
26.
Culture superantes of Escherichia coli from diarrhoea patients were tested in dog jejunal loops for thermostable (ST) and thermolabile (LT) enterotoxins. Pre-treatment with choleragenoid blocked LT but not ST. Glucose was found to reduce fluid accumulation induced by both types of enterotoxin. The findings confirm and extend previous evidence of similarities between cholera toxin and E. coli LT and differences between it and E. coli ST.  相似文献   
27.
OBJECTIVES: There is no curative therapy for recurrent respiratory papillomatosis. Unmethylated dinucleotides of cytosine and guanine (CpG) are potent immune stimulants that have shown efficacy against tumors as monotherapy, as vaccine adjuvants, and in combination with chemotherapies. We examined the therapeutic effect of CpG oligodeoxynucleotides in the treatment of papillomavirus in a cottontail rabbit model (CRPV). METHODS: Twenty rabbits were infected with CRPV; 10 were treated with 11 weekly CpG inoculations while treatment control rabbits received intralesional saline solution. Eight rabbits (4 treatment, 4 control) were rechallenged with CRPV 17 weeks after the initial viral challenge and monitored for new papilloma development. RESULTS: Papillomas developed in all 20 rabbits (100%) within 4 weeks of infection. The diagnosis was confirmed histologically. There was no difference in the average tumor burden between the treatment and control groups after 11 weeks of CpG treatments or after 9 additional weeks of observation. There was no difference between the groups in papilloma size at the site of the injections, nor was there eradication of papillomas at remote sites in either group. No new papillomas developed in any of the 8 animals that were rechallenged. CONCLUSIONS: We have reproduced an effective mammalian papilloma model for preclinical immunotherapeutic testing. Despite the potency of CpG in triggering host immunity, CpG oligodeoxynucleotide did not show a therapeutic effect against the large papilloma burdens tested in this study. The lack of effect suggests that either enhanced papilloma antigen presentation or targeting of immune-evasive mechanisms used by the papillomas is needed to treat bulky disease with an immunotherapeutic strategy.  相似文献   
28.
OBJECTIVES/HYPOTHESIS: The aim of the study was to investigate the use of an ultrasonic surgical aspirator for creation of the laryngeal cartilage window during medialization thyroplasty. STUDY DESIGN: Basic science. METHODS: Forty thyroplasty windows were constructed in fresh, unpreserved cadaver larynges. A 6 x 13-mm rectangular window and a 4 x 4-mm round window were created on each side of the larynges in a symmetrical fashion. A standard surgical drill with a 3-mm cutting burr was used on one side; the ultrasonic surgical aspirator was used on the contralateral side. The time required for window construction was recorded, as was the status of the inner perichondrium at window completion. RESULTS: For creation of the 6 x 13-mm window, a mean time of 128 seconds was required using a standard surgical drill. The mean time using the ultrasonic aspirator device was 91 seconds for the window of the same size (P < .008). For the 4-mm round window, drilling completed the task in a mean time of 63 seconds, compared with 40 seconds (P < .016) for the ultrasonic aspirator. On creation of the 6 x 13-mm window, there were 4 of 10 perichondrial violations in the drilled specimens, and there were no violations in creation of the window of the same size with the ultrasonic aspirator (P = .12). The 4-mm round window had no perichondrium violations in the standard drill group and only 1 of 10 violations in the ultrasonic aspirator group (P = .99). CONCLUSION: The study suggested that the ultrasonic surgical aspirator device may be an effective, efficient alternative to the standard drill for medialization thyroplasty window creation. Prospective clinical trials are warranted to better characterize its applicability.  相似文献   
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30.
Hirschhorn N  Nalin DR  Cash RA 《Pediatrics》2002,109(4):713-5; author reply 713-5
  相似文献   
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