Effect of Hyperbaric Oxygen on the Growth of Intracranial Glioma in Rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Numerous studies have confirmed that hyperbaric oxygen (HBO) in combination with radiotherapy or chemotherapy may increase the efficacy of radiotherapy or chemotherapy in patients with glioma. However, whether HBO therapy alone may inhibit or promote the growth of malignant tumors remains controversial. This study aimed to investigate the effect of HBO on the growth of glioma in rats, and the impact of HBO on the expression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1-alpha (HIF-1α), angiogenesis, and apoptosis of glioma cells.</p><p><b>METHODS</b>Male Sprague-Dawley rats were treated with or without HBO after glioma cell inoculation and followed for up to 16 days postinoculation. Rats were randomized to receive bilateral forelimb function tests (n = 20 per group) and head magnetic resonance imaging (n = 5 per group). Differences between HBO and control groups were tested using 2-sample independent t-tests and changes over time within treatment groups were analyzed using a repeated measurement analysis of variance with Bonferroni correction. The effect of HBO on the expression of VEGF, HIF-1α, von Willebrand factor, angiogenesis, and tumor cell apoptosis were also examined (n = 5 per group).</p><p><b>RESULTS</b>Forelimb function scores were reduced in both HBO-treated and control groups. HBO-treated rats had significantly larger tumor volume and more water in the cerebellum compared with control rats. The intratumoral expression of VEGF was significantly higher in HBO-treated rats compared with control rats (23.2% vs. 13.3%, P = 0.002). HIF-1α was significantly increased in HBO-treated rats compared with controls in the expression of both intratumoral (72.7% vs. 54.9%, P = 0.001) and peritumoral (2.6% vs. 1.9%, P = 0.003) cells. The intratumoral microvessel density (MVD) was significantly higher in the HBO group (15.6 vessels/field vs. 4.4 vessels/field, P < 0.001), and the peritumoral MVD was not significantly different between the two groups (P > 0.05). Apoptosis was significantly lower in HBO-treated rats compared with controls (44.4% vs. 82.8% for intratumoral; 10.1% vs. 77.5% for peritumoral, both P < 0.001).</p><p><b>CONCLUSIONS</b>The current results demonstrate that HBO alone may promote tumor growth, and is therefore not suitable to treat patients with gliomas with neurological deficits or disorders with HBO alone. If HBO must be used as a mean of rehabilitation, it is recommended that HBO should be combined with radiotherapy or chemotherapy.</p>

Increased expression of osteopontin in brain arteriovenous malformations / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The precise mechanisms responsible for the development and growth of intracranial arteriovenous malformations (AVMs) remain unclear. Osteopontin (OPN) is a phosphorylated glycoprotein with diverse functions. This study aimed to analyze the expression of OPN in human brain AVMs.</p><p><b>METHODS</b>The AVM nidus was surgically obtained from patients with AVM, whereas control brain artery specimens were surgically obtained from patients with epilepsy. Reverse transcription-polymerase chain reaction (RT-PCR) was used to examine the expression of OPN mRNA in biopsy specimens. OPN protein expression was localized by immunohistochemistry. The statistical differences between different groups were assessed by two-way analysis of variance (ANOVA).</p><p><b>RESULTS</b>We analyzed 36 brain AVM specimens and 8 control brain artery specimens. Eleven patients with brain AVM received embolization treatment, and five underwent gamma knife radiotherapy before resection. Nineteen patients with brain AVM had a history of hemorrhage from AVMs. The expression of OPN mRNA was significantly higher in AVMs than that in the control specimens (25.76 ± 2.71 vs. 21.46 ± 2.01, P < 0.01). There was no statistically significant difference in the extent of OPN mRNA expression between the AVM group with and that without history of hemorrhage (26.13 ± 2.45 vs. 25.34 ± 2.99) or gamma knife radiotherapy (24.39 ± 2.10 vs. 24.53 ± 1.85). However, the difference between the AVM group with and that without embolization treatment history was statistically significant (24.39 ± 2.10 vs. 28.80 ± 1.13, P < 0.01). In the group with gamma knife radiotherapy history, OPN expression was found in arteries with early-stage radio-effect.</p><p><b>CONCLUSIONS</b>OPN may contribute to the vascular instability of brain AVMs. It may play an important role in the pathophysiological process related to embolization treatment.</p>

Diagnostic value of contrast-enhanced intraoperative Doppler sonography for cerebral arteriovenous malformations compared with angiography / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Intraoperative Doppler sonography has been used in the neurosurgical operating room for the localization and description of cerebral arteriovenous malformations (AVMs). This study aimed to investigate the clinical value of contrast-enhanced intraoperative Doppler sonography, including its ability to assess the location and identify of feeding arteries in patients with AVMs and to compare this method with angiography.</p><p><b>METHODS</b>Twenty-three patients with cerebral AVMs who were diagnosed using angiography, were examined with contrast-enhanced intraoperative Doppler sonography. As an echo-enhancing agent, Sulphur Hexafluoride Microbubbles for Injection ("SonoVue") was administered intravenously in all patients. Sonogram results were reviewed and correlated with angiographic findings. For statistical analysis, the Wilcoxon signed-rank test was applied.</p><p><b>RESULTS</b>Angiography identified 20 AVM lesions in the anterior or middle fossa and 3 in the posterior fossa. Contrast-enhanced intraoperative Doppler was somewhat less sensitive for only detecting 21/23 (91.3%) of the AVM lesions. Additionally, contrast-enhanced intraoperative Doppler slightly underestimated AVM size compared with angiographic findings but showed feeding arteries with sufficient acoustic properties. In 15 patients, angiography revealed a coincidental blood supply from another intracranial vessel, which was missed by contrast-enhanced intraoperative Doppler sonography.</p><p><b>CONCLUSIONS</b>In a limited group of patients with AVMs, contrast-enhanced intraoperative Doppler sonography was a less sensitive but useful and simple method for the detection of AVMs in contrast to angiography. No specific untoward effects were attributed to the use of "SonoVue" as a contrast-enhancing substance.</p>