Propofol Causes Sustained Ca2+ Elevation in Endothelial Cells by Stimulating Ryanodine Receptor and Suppressing Plasmalemmal Ca2+ Pump.

ABSTRACT: Propofol, a general anesthetic administered intravenously, may cause pain at the injection site. The pain is in part due to irritation of vascular endothelial cells. We here investigated the effects of propofol on Ca2+ transport and pain mediator release in human umbilical vein endothelial cells (EA.hy926). Propofol mobilized Ca2+ from cyclopiazonic acid (CPA)-dischargeable pool but did not cause Ca2+ release from the lysosomal Ca2+ stores. Propofol-elicited Ca2+ release was suppressed by 100 µM ryanodine, suggesting the participation of ryanodine receptor channels. Propofol did not affect ATP-triggered Ca2+ release but abolished the Ca2+ influx triggered by ATP; in addition, propofol also suppressed store-operated Ca2+ entry elicited by CPA. Ca2+ clearance during CPA-induced Ca2+ discharge was unaffected by a low Na+ (50 mM) extracellular solution, but strongly suppressed by 5 mM La3+ (an inhibitor of plasmalemmal Ca2+ pump), suggesting Ca2+ extrusion was predominantly through the plasmalemmal Ca2+ pump. Propofol mimicked the effect of La3+ in suppressing Ca2+ clearance. Propofol also stimulated release of pain mediators, namely, reactive oxygen species and bradykinin. Our data suggest propofol elicited Ca2+ release and repressed Ca2+ clearance, causing a sustained cytosolic [Ca2+]i elevation. The latter may cause reactive oxygen species and bradykinin release, resulting in pain.

Embolization followed by surgery for treatment of perimedullary arteriovenous fistula causing acute myelopathy.

BACKGROUND: Perimedullary arteriovenous fistula (AVF) is rare. There are three subtypes, and the treatment strategies for each are different. Subtype B (multiple fistulas) can be treated by either embolization or surgery. On the basis of a case from our treatment experience, we propose a method for achieving optimal outcome while minimizing nerve injury. CASE DESCRIPTION: A 51-year-old female was admitted to our hospital with acute myelopathy caused by a perimedullary AVF. Initially, we treated her by embolization using the chemical agent Onyx. Her symptoms improved immediately but gradually returned beginning 1 week later. Two months later, the symptoms had returned to pretreatment status, so we removed the fistulas surgically. Severe adhesions between nerve and occult venous varices were noted during the operation. Afterward, the patient's symptoms improved significantly. Histopathological sections showed an inflammatory reaction around the varices. CONCLUSIONS: We initially considered several possible reasons for the return of symptoms: (a) Hypoperfusion of the spinal cord; (b) mass effect of the occult vein varices; (c) residual AVF or vascular remodeling resulting in recurrent cord hypertension; (d) Onyx-induced perivascular inflammation resulting in nerves adhering to each other and to occult venous varices. Clinical, surgical, and pathological findings ruled out the first three, leaving Onyx-induced perivascular inflammation as the probable reason. Given our treatment experience and the pros and cons of the two methods, we propose that initial embolization followed by surgery after 5 days to remove occult venous varices is the ideal strategy for treating perimedullary AVF of subtype B.

Isolated intraventricular aspergillosis in a schizophrenic patient.

Intracranial aspergillosis of the lateral ventricle is a rare condition and has not been reported in a schizophrenic patient. We report a 39-year-old male patient with underlying schizophrenia and a rapid deterioration of consciousness. Initial cranial computed tomographic images revealed focal dilatation of the posterior part of the right lateral ventricle with a severe mass effect and midline shift. The patient received an emergency endoscopic ventriculostomy, and the resected mass was proven to be aspergillus. The patient was postoperatively treated by prolonged external ventricular drainage and antifungal medication, with no recurrence of aspergillosis at the 12-month follow-up.

White Matter tract involvement in brain tumors: a diffusion tensor imaging analysis.

BACKGROUND: Characterization of WM alteration using MR imaging is important in the pre- and intraoperative assessment of brain tumors. This study characterizes the extent and severity of WM tract alterations near brain tumors using DTI in an effort to determine preoperative viability or resectability of the adjacent WM tracts. Fractional anisotropy is an important DTI-derived metric of MR imaging. METHODS: Twenty-one patients underwent MR DTI. Eighty-six WM tracts composed of 43 WM lesions paired with 43 contralateral WM hemispheric controls were categorized using FA. Neuroradiologists categorized the WM tracts as edematous, displaced, disrupted, or infiltrated with tumor using directionally encoded color maps. A mixed model analysis was used to compare FA. RESULTS: Of the lesioned tracts, 5 were scored as edema, 9 as infiltration, 18 as displacement, and 11 as disruption. A significant DeltaFA(%) was found between the lesioned and contralateral hemispheres only in WM disruption (P = .0056). Both edema FA and disruption FA are significantly less than displacement FA (P < .05). The FA change (DeltaFA(%) = [FA(lesion) - FA(normal)]/FA(normal) x 100%) on the lesioned side was calculated. A DeltaFA% less than -30% is likely to be associated with WM disruption. A positive DeltaFA% is likely to be associated with edema or displacement, and a DeltaFA% between 0% and -30% is likely to be associated with WM displacement or infiltration. CONCLUSIONS: Quantitative analysis of DTI data may provide insight as to whether WM tracts are salvageable preoperatively.

Endovascular repair of tracheo-innominate artery fistula.

Innominate arterial wall rupture with pseudoaneurysm formation was found during angiography in a 39-year-old woman 2 days after she had undergone percutaneous dilatational tracheostomy. Endovascular stent surgery and balloon angioplasty were performed but these procedures failed to control the massive bleeding resulting from an endoleak. We report the clinical presentations and describe the treatment of a tracheo-innominate artery fistula in our patient. We also reviewed the algorithms of management and the rescue options for treating a tracheo-innominate artery fistula.

Stromal cell-derived factor-1 alpha promotes neuroprotection, angiogenesis, and mobilization/homing of bone marrow-derived cells in stroke rats.

Stromal cell-derived factor (SDF)-1alpha is involved in the trafficking of hematopoietic stem cells from bone marrow to peripheral blood, and its expression is increased in the penumbra of the ischemic brain. In this study, SDF-1alpha was found to exert neuroprotective effects that rescued primary cortical cultures from H(2)O(2) neurotoxicity, and to modulate neurotrophic factor expression. Rats receiving intracerebral administration of SDF-1alpha showed less cerebral infarction due to up-regulation of antiapoptotic proteins, and they had improved motor performance. SDF-1alpha injection enhanced the targeting of bone marrow (BM)-derived cells to the injured brain, as demonstrated in green fluorescent protein-chimeric mice with cerebral ischemia. In addition, increased vascular density in the ischemic cortex of SDF-1alpha-treated rats enhanced functional local cerebral blood flow. In summary, intracerebral administration of SDF-1alpha resulted in neuroprotection against neurotoxic insult, and it induced increased BM-derived cell targeting to the ischemic brain, thereby reducing the volume of cerebral infarction and improving neural plasticity.

Progressive multifocal leukoencephalopathy in an AIDS patient.

Progressive multifocal leukoencephalopathy (PML) is a demyelinating brain disease caused by Jamestown Canyon virus (JCV). This disease is an important cause of morbidity and mortality in acquired immunodeficiency syndrome (AIDS) patients. We report a 34-year-old man infected with HIV-1 who presented with frequent general tonic clonic seizure and left side weakness for 2 months. Clinical features and magnetic resonance imaging (MRI) findings with hyperintensity on T2-weighted imaging and low density on T2 fluid attenuated inversion recovery involving multiple white matter were compatible with PML. He died of sepsis 2 months after diagnosis. Autopsy demonstrated progressive multifocal leukoencephalopathy according to characteristic histopathologic picture with multifocal demyelination, bizarre astrocytes formation and basophilic intranuclear inclusion bodies in the oligodendrocytes. JCV genome was demonstrated in the nucleus of oligodendrocytes using in situ hybridization. In conclusion, in AIDS patients with neurologic signs and typical MRI findings who present with multifocal demyelination lesions, PML should be diagnosed clinically.

Unusual magnetic resonance characteristics of a cerebellopontine angle epidermoid cyst with upper cervical spinal canal extension.

We present a 27-year-old woman with an epidermoid cyst at the cerebellopontine (CP) angle with caudal extension into the upper cervical spinal canal. The lesion showed unusual hyperintensity on T1-weighted images, and hypointensity on T2-weighted images. We used microneurosurgical techniques for tumour dissection and excision. To our knowledge, this is the fifth example in Index Medicus/MEDLINE of histopathologically proven CP angle epidermoid with cervical spine extension.

Microelectrode recording can be a good adjunct in magnetic resonance image-directed subthalamic nucleus deep brain stimulation for parkinsonism.

BACKGROUND: The contribution of MER to improving bilateral STN-DBS is debatable. To resolve the controversy and elucidate the role of MER in DBS, we compared the outcome of bilateral STN-DBS surgery with and without MER in parkinsonian patients. METHODS: From February 2002 to November 2002, the first 7 of 13 consecutive parkinsonian patients received STN-DBS without MER (group A), and the last 6 received STN-DBS with MER (group B). Pre- and postoperative assessments included scoring of UPDRS with video taping, and MR images. RESULTS: The mean Hoehn and Yahr stage was 3.6 in group A and 4.0 in group B. The mean follow-up was 7.4 months for group A and 5.3 months for group B. The mean coordinates of the tip of the permanent electrode relative to the mid-commissural point were x = 8.1 mm, y = 4.3 mm, and z = 5.9 mm for group A and x = 10.6 mm, y = 4.1 mm, and z = 6.9 mm for group B. When levodopa was withdrawn from group A for 12 hours at follow-up, the postoperative UPDRS total score improved by 27.6% (P = .01) and the motor score by 25.4% (P = .02); their LEDD decreased by 17.5% (P = .03). In group B, the postoperative UPDRS total score improved by 49.3% (P = .00002) and the motor score by 45.2% (P = .0004); LEDD decreased by 48.5% (P = .01). CONCLUSIONS: Although STN-DBS is a promising surgical modality for advanced parkinsonian patients, there is an inevitable learning curve associated with adopting this new procedure. Intraoperative MER is an effective way to ensure correct electrode placement in the STN. With the assistance of intraoperative MER, the outcome of STN-DBS can be improved significantly.

Intravascular lymphomatosis mimicking acute disseminated encephalomyelitis: a case report.

We describe the clinical, radiologic, and postmortem findings in a 49-year-old woman with intravascular lymphomatosis. The patient presented with progressive limb weakness followed by progressive disseminated cerebral neurologic symptoms. Disseminated encephalomyelitis was suspected due to the clinical and radiologic findings. Steroid pulse therapy and intravenous immunoglobulin were given but did not help. The patient died of multiple organ failure 3 months after the onset of symptoms. A diagnosis of disseminated intravascular large B-cell lymphomatosis was established based on findings from histopathology and immunohistochemistry studies on autopsy specimens of the brain and other visceral organs collected postmortem.

Functional recovery of stroke rats induced by granulocyte colony-stimulating factor-stimulated stem cells.

BACKGROUND: Stroke is a leading cause of death and disability worldwide; however, no effective treatment currently exists. METHODS AND RESULTS: Rats receiving subcutaneous granulocyte colony-stimulating factor (G-CSF) showed less cerebral infarction, as evaluated by MRI, and improved motor performance after right middle cerebral artery ligation than vehicle-treated control rats. Subcutaneous administration of G-CSF enhanced the availability of circulating hematopoietic stem cells to the brain and their capacity for neurogenesis and angiogenesis in rats with cerebral ischemia. CONCLUSIONS: G-CSF induced increases in bone marrow cell mobilization and targeting to the brain, reducing the volume of cerebral infarction and improving neural plasticity and vascularization.

Primary angiosarcoma of the cranial vault: a case report and review of the literature.

BACKGROUND: Angiosarcoma is a rare neoplasm. It is most likely to affect the scalp in elderly people and involvement of the cranium is uncommon. We report a case of primary malignant angiosarcoma of the cranial vault. CASE DESCRIPTION: An 82-year-old man presented with right hemiparesis, deformity of the cranium and mildly swollen scalp. Further studies disclosed bilateral parietal lesions, with destruction of the dura matter and infiltration of the brain parenchyma. Thrombocytopenia was found. Faint enhancement of the lesions was seen on magnetic resonance imaging (MRI) after i.v. administration of contrast medium with gadolinium. The tumor was excised including the affected portion of the skull and dura matter. Histologic examination revealed typical pictures of angiosarcoma with immunohistochemical evidence of factor VIII-related antigen. Postoperative radiotherapy was employed. The patient remained well at 10 months postoperative follow up. CONCLUSION: Primary angiosarcoma of the cranium is sometimes difficult to differentiate from trauma on clinical examination. We review the literature pertaining to the pathogenesis, clinical course and treatment of this condition. Determination of platelet count may be helpful in monitoring the progression of the disease. The tumor may show faint enhancement on MRI.

Imaging of renal tuberculosis in eastern Taiwan: correlation with clinical course and different communities.

Hualien, located in eastern Taiwan, is a relatively isolated district. The population is composed of different ethnic communities. Our hospital is the only medical center in eastern Taiwan, so is the most important referral hospital for epidemic diseases. After reviewing our collected cases of renal tuberculosis (TB), we observed a great diversity in staging and outcomes. The aim of this study was to classify different imaging presentations and clinical outcomes in the ethnic communities represented by these cases (non-aboriginal and aboriginal). We retrospectively reviewed 22 cases from 1991 to 2001. We reviewed laboratory data, radiologic reports, and clinical outcomes. Before TB was proved by biopsy or culture, patients were not treated with an anti-TB regimen. Roentgenography showed that 68% of patients had renal calcification, 59% had dilated calyces, 55% had lung involvement, and 41% had auto-nephrectomy. The proportion of mild and severe forms was significantly different between aboriginal and non-aboriginal groups (0.05 > p > or = 0.00409). From this series, we recommend routine plain film roentgenography, including chest roentgenography and kidney, ureter, and bladder or abdominal roentgenography, followed by intravenous urography or computerized tomography as investigative tools for renal TB. Based on the significantly different outcomes of the disease between aboriginal and non-aboriginal groups, a stronger health education program for the isolated district in eastern Taiwan is necessary.

Primary medulla oblongata germinoma: a case report and review of the literature.

We describe a case of primary intracranial medulla oblongata germinoma in a 16-year-old girl who presented with progressive headache and blurred vision. Magnetic resonance imaging demonstrated a heterogeneous exophytic mass arising from dorsal aspect of medulla oblongata with extension into fourth ventricle. The differential diagnosis for this patient had included ependymoma, exophytic glioma, medulloblastoma and choroid plexus papilloma. After surgical resection and radiation therapy, she remains alive and recurrence-free for 7 years.