Delayed Ischemic Stroke after Flow Diversion of Large Posterior Communicating Artery Aneurysm.

For securing large, giant, and wide-neck aneurysms, conventional coil embolization has substantial limitations, such as incomplete occlusion, recanalization, and a high recurrence rate. To overcome these limitations, a novel paradigm was suggested and, as a result, flow-diverting device was developed. The flow-diverting device is an innovative and effective technique to allow securing of large, giant, and wide-neck aneurysms. In numerous studies, the flow-diverting device has shown better outcomes than coil embolization. However, the flow-diverting device has also some risks, including rupture of aneurysm, intracerebral hemorrhage, and ischemic stroke. In addition, with more experience, unexpected complications are also reported.5)7) In the present case, we experienced a delayed ischemic stroke at 27 days after endovascular treatment. The patient had multiple aneurysms and, among them, we treated a large posterior communicating artery aneurysm using Pipeline™ Embolization Device. The patient was tolerable for 25 days, but then suddenly presented intermittent right hemiparesis. In the initial diffusion magnetic resonance imaging (MRI), there was no acute lesion; however, in the follow-up MRI, an acute ischemic stroke was found in the territory of anterior choroidal artery which was covered by Pipeline Embolization Device. We suspect that neo-intimal overgrowth or a tiny thrombus have led to this delayed complication. Through our case, we learned that the neurosurgeon should be aware of the possibility of delayed ischemic stroke after flow diversion, as well as, long-term close observation and follow-up angiography are necessary even in the event of no acute complications.

Anabolic effects of Peniel 2000, a peptide that regulates TGF-ß1 signaling on intervertebral disc degeneration.

STUDY DESIGN: An in vitro study with bovine intervertebral disc (IVD) cells and an in vivo study with a rabbit disc degeneration model on the extracellular matrix metabolism by a biglycan-derived peptide (Peniel 2000; P2K). OBJECTIVE: To investigate the mechanism for P2K-induced increases in extracellular matrix and in vitro and in vivo effects of the peptide on IVD. SUMMARY OF BACKGROUND DATA: Transforming growth factor-ß (TGF-ß) has a functional versatility on the metabolism of IVD cells, suggesting that the regulation of TGF-ß signaling is important in IVD degeneration. P2K was explored by an in silico drug discovery strategy to regulate TGF-ß signaling. METHODS: The putative target of P2K was verified by Biacore 3000 analysis and affinity purification using biotin-P2K. A monolayer culture system of bovine IVD cells was used to demonstrate the mechanism underlying the anabolic effects of P2K. Smad signaling and extracellular matrix metabolism of the IVD cells were investigated by Western blot and reverse transcription-polymerase chain reaction, respectively. The in vivo effect of P2K on degenerated disc was investigated using a rabbit model of disc degeneration. In 14 New Zealand white rabbits, disc degeneration was induced by percutaneous annular punctures. After 4 weeks, 3 consecutive discs in the same animal were treated with 5% lactose or P2K per disc. Twelve weeks after the treatment, the regenerative activity in the disc was examined by radiography, magnetic resonance imaging, and biochemical and histological analyses. RESULTS: Direct binding of P2K to an active form of TGF-ß1 was shown. Type II collagen and aggrecan were increased in TGF-ß1/P2K-treated bovine IVD cells, compared with nontreated and TGF-ß1-treated cells.In in vivo analysis, a single injection of P2K increased the disc height (P < 0.001) on the radiographs and improved the magnetic resonance imaging grade (P < 0.05) compared with controls. Biochemical analysis, showed a significant increase in PG content because of P2K treatment (P < 0.05). Histological analysis using disc degeneration grades demonstrated improvement in P2K-treated discs (P <0.01). CONCLUSION: A novel peptide, P2K, regulating TGF-ß1 signaling had an anabolic effect on bovine IVD cells and rabbit degenerated discs. The results suggest that P2K has considerable potential as a treatment of degenerative disc disease.

Comparison of Serum CRP and Procalcitonin in Patients after Spine Surgery.

OBJECTIVE: Classical markers of infection cannot differentiate reliably between inflammation and infection after neurosurgery. This study investigated the dynamics of serum procalcitonin (PCT) in patients who had elective spine surgeries without complications. METHODS: Participants were 103 patients (47 women, 56 men) who underwent elective spinal surgery. Clinical variables relevant to the study included age, sex, medical history, body mass index (BMI), site and type of surgery, and surgery duration. Clinical and laboratory data were body temperature, white blood cell count (WBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and PCT, all measured preoperatively and postoperatively on days 1, 3, and 5. RESULTS: PCT concentrations remained at <0.25 ng/mL during the postoperative course except in 2 patients. PCT concentrations did not correlate with age, sex, DM, hypertension, BMI, operation time, operation site, or use of instrumentation. In contrast, CRP concentrations were significantly higher with older age, male, DM, hypertension, longer operation time, cervical operation, and use of instrumentation. CONCLUSION: PCT may be useful in the diagnosing neurosurgical patients with postoperative fever of unknown origin.

Coordinated change of a ratio of methylated H3-lysine 4 or acetylated H3 to acetylated H4 and DNA methylation is associated with tissue-specific gene expression in cloned pig.

Various cell types in higher multicellular organisms are genetically homogenous, but are functionally and morphologically heterogeneous due to the differential expression of genes during development, which appears to be controlled by epigenetic mechanisms. However, the exact molecular mechanisms that govern the tissue-specific gene expression are poorly understood. Here, we show that dynamic changes in histone modifications and DNA methylation in the upstream coding region of a gene containing the transcription initiation site determine the tissue-specific gene expression pattern. The tissue-specific expression of the transgene correlated with DNA demethylation at specific CpG sites as well as significant changes in histone modifications from a low ratio of methylated H3- lysine 4 or acetylated H3-lysine 9, 14 to acetylated H4 to higher ratios. Based on the programmed status of transgene silenced in cloned mammalian ear-derived fibroblasts, the transgene could be reprogrammed by change of histone modification and DNA methylation by inhibiting both histone deacetylase and DNA methylation, resulting in high expression of the transgene. These findings indicate that dynamic change of histone modification and DNA methylation is potentially important in the establishment and maintenance of tissue-specific gene expression.