Expression and significance of sonic hedgehog signaling pathway-related components in brainstem and supratentorial astrocytomas / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Studies have shown that abnormal activation of the sonic hedgehog pathway is closely related to tumorigenesis in central nervous system. This study aimed to investigate the role of the sonic hedgehog signaling pathway in the occurrence of brainstem and supratentorial glioma.</p><p><b>METHODS</b>Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry were used to detect the expression of sonic hedgehog-related components in 5 specimens of normal brain tissue, 10 of grade II brainstem glioma, and 10 of grade II supratentorial glioma. The significance of differences between two groups was determined using the Mann-Whitney U test or the two-sample test according to the results of normality distribution tests.</p><p><b>RESULTS</b>The mRNA expression levels of sonic hedgehog-related genes were higher in brainstem astrocytomas than in supratentorial astrocytomas and normal brain tissue. The level of protein patched homolog 1 (PTCH1) was significantly higher in brainstem astrocytomas than in supratentorial astrocytomas and normal brain tissue (P < 0.01). Immunohistochemistry semi-quantitative analysis was consistent with the qRT-PCR result that PTCH1 expression was increased significantly in brainstem astrocytomas at the protein level (P < 0.05).</p><p><b>CONCLUSIONS</b>Enhanced PTCH1 expression and activation of the sonic hedgehog pathway are involved in brainstem glioma. This may be related to the difference in malignant biological behavior between brainstem and hemispheric glioma, and could be an ideal therapeutic target in brainstem glioma.</p>

Histological changes and ICAM-1 and TMMP-9 expressions in the internal carotid arteries of patients with moyamoya disease / 中华神经医学杂志

Objective To observe the histopathological and ultrastructural changes,alterations in the expressions of type Ⅳ collagenases(MMP-2 and MMP-9),the tissue inhibitors(TIMP-1 and TIMP-2)and intercellular adhesion molecule-1(ICAM-1)in the internal carotid arteries(ICAs)of patients with moyamoya disease(MD),and explore the pathogenesis of MD.Methods The bilateral ICAs were obtained during autopsy from two MD patients.HE staining and Weigert staining was used for histological observation,and transmission electron microscopy Was employed to observe the ultrastructure of the ICAS.The expression of ICAM-1 in the ICAs was detected using immunohistochemical staining,and the mRNA expressions of MMLP-2,MMP-9,TMP-1 and TIMP-2 were assayed using in situ hybridization.The ICA specimens from two patients died from non-vascular diseases were used as the control.Restilts HE staining revealed thinning of the ICAs of the MD patients with luminal stenosis,obstruction and calcification.Weigert staining identified fibrous thickening of the intima,thinning and fragmentation of the elastica interna(EI)and elastica externa(EE),degenerafion of the smooth muscle cells in the media,and thinning and local exfoliation of the adventitia.Immunohistochemistry showed ICAM-1 expression in the ICAs of both MD and control patients,but the MD patients exhibited a stronger ICAM-1 positivity in the ICAs localized primarily in the tunica intima.The ICA wall was positive for MMP-9 mRNA expression,which Was especially intense in the elastica intema,as shown by in situ hybfidization.Conslusions The high expression of MMP-9 and ICAM-1,destruction of the elastic layer and adventitia,and collapse of the vascular wall result in luminal stenosis or everi obstruction of the ICAs,which can be associated with the occuITence of MD.

Intraoperative facial motor evoked potentials monitoring with transcranial electrical stimulation for preservation of facial nerve function in patients with large acoustic neuroma / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Although various monitoring techniques have been used routinely in the treatment of the lesions in the skull base, iatrogenic facial paresis or paralysis remains a significant clinical problem. The aim of this study was to investigate the effect of intraoperative facial motor evoked potentials monitoring with transcranial electrical stimulation on preservation of facial nerve function.</p><p><b>METHOD</b>From January to November 2005, 19 patients with large acoustic neuroma were treated using intraoperative facial motor evoked potentials monitoring with transcranial electrical stimulation (TCEMEP) for preservation of facial nerve function. The relationship between the decrease of MEP amplitude after tumor removal and the postoperative function of the facial nerve was analyzed.</p><p><b>RESULTS</b>MEP amplitude decreased more than 75% in 11 patients, of which 6 presented significant facial paralysis (H-B grade 3), and 5 had mild facial paralysis (H-B grade 2). In the other 8 patients, whose MEP amplitude decreased less than 75%, 1 experienced significant facial paralysis, 5 had mild facial paralysis, and 2 were normal.</p><p><b>CONCLUSIONS</b>Intraoperative TCEMEP can be used to predict postoperative function of the facial nerve. The decreased MEP amplitude above 75 % is an alarm point for possible severe facial paralysis.</p>