摘要:

OBJECTIVETo determine the expression of matrix metalloproteinases (MMP)-1, -2, and -3 and the tissue inhibitors of metalloproteinases (TIMP)-1, -2, and -3 in 12 tissue samples from normal pituitary glands and in 28 human pituitary tumors ranging from Grade 0 to Grade IV, and to establish a correlation between the level of expression of MMPs and TIMPs and the tumor grade.METHODSThe expression of MMPs and TIMPs was determined by Western blotting. MMP activity was detected by gelatin zymography.RESULTSMMPs were expressed in the majority of tumors, and their levels of expression were unrelated to tumor grade or to their invasive phenotype. Some correlation was observed between MMP activity detected by zymography and tumor grade. TIMP-2 and TIMP-3 were poorly expressed in high-grade tumors and strongly expressed in normal pituitary glands and in the majority of low-grade tumors.CONCLUSIONNo correlation could be established between the invasive potential of tumors and MMP-1, -2, and -3 expression levels. Some correlation was observed between MMP activity detected by zymography and tumor grade. A good inverse correlation was observed between TIMP-2 and TIMP-3 expression levels and tumor grade. These data suggest that monitoring the expression of TIMP-2 and TIMP-3 or gelatinolytic activity could be of prognostic value.

ISSN:0148-396X    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

OBJECTIVEAmplification of the epidermal growth factor receptor (EGFR) is a common event in the molecular pathogenesis of high-grade astrocytic tumors, occurring in 50% of glioblastoma multiforme (GBM) cases. A subset of GBMs also express a constitutively phosphorylated truncated receptor (EGFRvIII). Expression of transfected EGFRvIII in cells has been reported to activate the Ras-mitogen-activated protein kinase pathway and to provide a growth advantage. Novel therapeutic agents targeting signal transduction pathways are entering early clinical trials; determination of which GBMs express EGFRvIII might help identify patients who might benefit from these biological agents.METHODSA cohort of 15 flash-frozen surgical specimens (12 GBMs, 2 gliosarcomas, and 1 adult low-grade glioma) were evaluated for EGFR and EGFRvIII expression and for EGFR activation status using immunohistochemical (IHC) analysis, Western blotting, and reverse transcription-polymerase chain reaction assays. Levels of activated Ras-guanosine triphosphate were measured using a nonradioactive luciferase-based technique. Mitogen-activated protein kinase activation was determined using a myelin basic protein assay. IHC analysis was performed on paraffin-embedded, formalin-fixed, pathological specimens. Normal control samples included white matter specimens distal to tumors (n = 5), a sample obtained during a lobectomy for treatment of epilepsy (n = 1), and cultured fetal human astrocytes (n = 1).RESULTSWe demonstrated higher levels of activated Ras and mitogen-activated protein kinase in GBM specimens, compared with normal brain tissue or the low-grade glioma. There was a very good correlation between results obtained using specialized molecular techniques and those obtained using routine IHC techniques. Screening for EGFRvIII expression may be of prognostic importance, because patients with EGFRvIII-positive tumors exhibited shorter life expectancies (mean survival time for patients with EGFRvIII-positive tumors, 4.5 ± 0.6 mo; mean survival time for patients with EGFRvIII-negative tumors, 11.2 ± 0.9 mo).CONCLUSIONWe demonstrated that routine IHC techniques using commercially available antibodies are capable of identifying which GBM specimens express EGFRvIII and whether the EGFRs are activated. Such a molecular classification of GBMs might allow us to determine which patients might benefit from biologically targeted therapies. In addition, characterization of specimens with respect to their EGFRvIII status seems to be of prognostic value.

ISSN:0148-396X    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

DURING WORLD WAR II, many doctors joined the military after completing their medical training. Civilian careers were put on hold until after the war was over. In 1942, Eben Alexander, Jr., joined the Air Force, then the United States Army, and served 4 years, much of it overseas, as a “3131C” neurosurgeon.

ISSN:0148-396X    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:0148-396X    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

OBJECTIVERhinocerebral mucormycosis is a clinical syndrome resulting from an opportunistic infection caused by a fungus of the orderMucorales. The prognosis of rhinocerebral mucormycosis, once considered uniformly fatal, remains poor. Even with early diagnosis and aggressive surgical and medical therapy, the mortality rate is high. We present a patient with rhinocerebral mucormycosis involving the paranasal sinuses and cranial base who experienced long-term survival after multimodality treatment. Clinical characteristics of the disease are discussed, and the literature is reviewed.CLINICAL PRESENTATIONA 24-year-old diabetic man presented with invasive rhinocerebral mucormycosis involving the paranasal sinuses, right middle fossa, and right cavernous sinus.INTERVENTIONThe patient underwent endovascular sacrifice of the involved carotid artery and radical resection of the cranial base, including exenteration of the cavernous sinus. Reconstruction with a local muscle flap was performed. He continued to receive intravenous and intrathecal administration of antibiotics.CONCLUSIONLong-term survival with invasive rhinocerebral mucormycosis is rare, but possible, with aggressive multimodality treatment, including carotid sacrifice for en bloc resection of the pathology, when indicated.

ISSN:0148-396X    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:0148-396X    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

OBJECTIVE AND IMPORTANCEPosterior fossa subarachnoid hemorrhage secondary to blunt head trauma is rarely associated with traumatic aneurysms of the posterior circulation.CLINICAL PRESENTATIONWe present three cases of posterior fossa subarachnoid hemorrhage from ruptured posteroinferior cerebellar artery (PICA) aneurysms after blunt head trauma. In each case, there was no associated penetrating injury or cranial fracture. All three patients presented with acute hydrocephalus requiring ventriculostomy. Two of the three patients had a proximal PICA aneurysm visible on emergent angiography. The remaining patient’s aneurysm, although not visible on his initial angiogram, was detected on a subsequent angiogram 72 hours later.INTERVENTIONAll patients underwent successful surgical clipping of their aneurysms. Two cases required sacrificing of the parent vessels because of the friable nature of the false aneurysms. In each case, severe symptomatic vasospasm occurred, requiring angioplasty. All three patients also required a ventriculoperitoneal shunt for persistent hydrocephalus.CONCLUSIONFeatures of these three cases and similar cases reported in the literature support the theory that vascular ruptures and traumatic aneurysms of the proximal PICA may be related to anatomic variability of the PICA as it transverses the brainstem. This variability predisposes individuals to vascular lesions, which occur in a continuum based on the severity of the injury. Posterior fossa subarachnoid hemorrhage after head injury requires a high index of suspicion and warrants aggressive diagnostic and therapeutic interventions.

ISSN:0148-396X    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

OBJECTIVEContinuous monitoring of jugular venous oxygen saturation (SjvO2) is useful in the management of severe head injury. Abnormally high SjvO2values can be caused by increased cerebral blood flow, decreased cerebral metabolism, brain death, contamination from extracerebral venous blood, or traumatic arteriovenous fistula.CLINICAL PRESENTATIONA 20-year-old man with severe head injury was diagnosed to have a traumatic dural carotid-cavernous sinus fistula on the day of trauma. Continuous left SjvO2monitoring from Days 4 to 12 revealed oxygen saturation ranging between 85 and 98%.INTERVENTIONSuperselective intracranial and extracranial venous sampling on Day 5 demonstrated marked regional heterogeneity in venous oxygen saturation as follows: superior sagittal sinus, 95 to 97%; straight sinus, 88%; right transverse sinus, 94%; left transverse sinus, 74%; right SjvO2, 95%; left SjvO2, 89%; the basilar plexus, 99%; right internal jugular vein, 98%; the left internal jugular vein, 94%. Extremely high oxygen saturation in the superior sagittal sinus and basilar plexus was attributed to severe brain damage and carotid-cavernous sinus fistula, respectively.CONCLUSIONAlthough jugular bulb oximetry is useful in the management of severe head injury, high oxygen saturation values should be interpreted with caution because they cannot show the intracranial heterogeneity of venous oxygen saturation.

ISSN:0148-396X    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:0148-396X    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

OBJECTIVE AND IMPORTANCETumors in the suprasellar region such as adenomas of the pituitary gland, craniopharyngiomas, nonneoplastic cystic lesions (especially Rathke’s cleft cysts), and meningiomas are frequently encountered in neurosurgical practice. Meningiomas originate from the arachnoid layer connected to the dura of the anterior or posterior clinoidal process, or the tuberculum, dorsum, or diaphragma sellae. Tumors originating from the pituitary stalk are rare. Such lesions may include germinomas, astrocytomas, histiocytosis X, hamartomas, and sarcoidosis. We report a patient with a suprasellar meningioma originating from the pituitary stalk with no connection to the adjacent dura.CLINICAL PRESENTATIONA 50-year-old man was assessed for impotence and loss of libido. Physical examination revealed no abnormalities. Endocrinological investigations disclosed nearly complete hypopituitarism, and magnetic resonance imaging revealed a suprasellar homogeneously enhancing tumor.INTERVENTIONComplete surgical resection was performed in an endoscope-assisted right-sided supraorbital craniotomy. The tumor originated from the pituitary stalk with no connection to the surrounding dura. The histopathological diagnosis was meningioma.CONCLUSIONAlthough meningiomas frequently occur in the suprasellar region, this patient with a suprasellar meningioma is unique because the tumor originated from the pituitary stalk with no connection to the surrounding dura. The absence of dural attachment has been described in 43 extracerebral meningiomas, but a suprasellar location has been reported only once previously. Recognition of this phenomenon is important, because meningiomas require a different therapeutic strategy than most other tumors of the pituitary stalk.

ISSN:0148-396X    

出版商:OVID    

年代:1999

数据来源: OVID