Cognition 6 years after surgical or medical therapy for coronary artery disease.

Objective: The choice of coronary artery bypass grafting (CABG) as an intervention for coronary artery disease has been clouded by concerns about postoperative cognitive decline. Long-term cognitive decline after CABG has been reported, but without appropriate control subjects, it is not known whether this decline is specific to CABG or related to other factors such as cerebrovascular disease.

Methods: This prospective, observational study of patients with diagnosed coronary artery disease included 152 CABG and 92 nonsurgical cardiac comparison patients from one institution.

Identification of A2B5+CD133- tumor-initiating cells in adult human gliomas.

Objective: Several studies have shown that human gliomas contain a small population of cells with stem cell-like features. It has been proposed that these "cancer stem cells" may be uniquely responsible for glioma formation and recurrence. However, human gliomas also contain an abundance of cells that closely resemble more differentiated glial progenitors.

Tuberous sclerosis: a primary pathology of astrocytes?

Purpose: Cortical tubers are epileptogenic lesions in patients with tuberous sclerosis complex (TSC). Giant cells and dysplastic neurons are pathological hallmarks of cortical tubers. Severe astrogliosis, which is invariably present in tubers, has attracted much less attention.

Neurocognitive outcomes 3 years after coronary artery bypass graft surgery: a controlled study.

Background: Cardiopulmonary bypass has been implicated in the late cognitive decline that has been reported after coronary artery bypass graft (CABG) surgery. Because most studies did not include a control group, a causal link of such decline with the use of cardiopulmonary bypass has not been established.

Methods: We compared changes in cognitive performance from baseline to 3 years in patients undergoing on-pump CABG (n = 152) with those of three control groups: patients with off-pump surgery (n = 75); with diagnosed coronary artery disease but no surgery (n = 99); and without coronary artery disease risk factors (n = 69).

Postoperative hydrocephalus in patients undergoing decompressive hemicraniectomy for ischemic or hemorrhagic stroke.

Objective: We have frequently observed the development of postoperative communicating hydrocephalus in patients undergoing decompressive hemicraniectomy. This condition may persist in some patients after cranioplasty and require permanent cerebrospinal fluid (CSF) diversion. To confirm an independent correlation between hemicraniectomy and the development of communicating hydrocephalus, and to detail the frequency and potential clinical factors contributing to this complication, we evaluated our series of patients undergoing hemicraniectomy for life-threatening increases in intracranial pressure secondary to ischemic or hemorrhagic stroke.

Evidence for cortical reorganization of language in patients with hippocampal sclerosis.

Naming is mediated by perisylvian cortex in the left (language-dominant) hemisphere, and thus, left anterior temporal lobe resection for pharmacologically intractable temporal lobe epilepsy (TLE) carries risk for post-operative naming decline. Interestingly, this risk is lower in patients with hippocampal sclerosis (HS) relative to those without HS (non-HS). Although the hippocampus has traditionally been considered a critical structure for memory, without contribution to naming, this pattern might implicate direct hippocampal naming involvement.

Early postoperative cognitive dysfunction and blood pressure during coronary artery bypass graft operation.

Objective: To determine the relationship between change in blood pressure during coronary artery bypass graft operations and early cognitive dysfunction.

Design: Cohort study.

Setting: Quaternary care facility.

Lack of B7 expression, not human leukocyte antigen expression, facilitates immune evasion by human malignant gliomas.

Objective: Lack of human leukocyte antigens and costimulatory molecules have been suggested as mechanisms by which human malignant gliomas avoid immune recognition and elimination.

Methods: Using quantitative multiparameter flow cytometric analysis, tumor cells from patients with glioblastoma multiforme (n = 18) were examined ex vivo for the expression of human leukocyte antigen Class I and II molecules and the costimulatory molecules B7-1 and B7-2. They were compared with reactive astrocytes from peritumoral brain metastases (n = 7), and astrocytes removed during nontumor surgery (n = 5).

Staged bilateral thalamic electrode implantation utilizing frameless stereotactic guidance.

Deep brain stimulation (DBS) for medically intractable Parkinson's disease (PD) is well established, but carries the inconveniences of frame-based neurosurgery. Previous reports have demonstrated that ventricular shunt placement and some functional procedures can be accurately performed using frameless stereotaxy. We present a report indicating that staged deep brain electrode placement can be accurate and efficacious using a frameless skull-mounted guide.

An in vivo correlate of exercise-induced neurogenesis in the adult dentate gyrus.

With continued debate over the functional significance of adult neurogenesis, identifying an in vivo correlate of neurogenesis has become an important goal. Here we rely on the coupling between neurogenesis and angiogenesis and test whether MRI measurements of cerebral blood volume (CBV) provide an imaging correlate of neurogenesis. First, we used an MRI approach to generate CBV maps over time in the hippocampal formation of exercising mice.

Distribution of auditory and visual naming sites in nonlesional temporal lobe epilepsy patients and patients with space-occupying temporal lobe lesions.

Purpose: Current knowledge regarding the topography of essential language cortex is based primarily on stimulation mapping studies of nonlesional epilepsy patients. We sought to determine whether space-occupying temporal lobe lesions are associated with a similar topography of language sites, as this information would be useful in surgical planning.

Methods: We retrospectively compared the topography of auditory and visual naming sites in 25 nonlesional temporal lobe epilepsy patients ("nonlesional") and 18 patients with space-occupying lesions ("lesional") who underwent cortical language mapping before left temporal resection.

Defective receptor expression and dendritic cell differentiation of monocytes in glioblastomas.

Objective: Better characterization of the changes that occur in the circulating monocytes of patients with glioblastoma has become more important recently as monocyte-derived dendritic cells are used as adjuvants in the development of glioma vaccines. This study seeks to develop understanding of the phenotypic changes that occur in circulating monocytes of patients with intracranial cancer and to assess the ability of these cells to differentiate into mature dendritic cells.

Methods: Monocyte expression levels of HLA-ABC, HLA-DR, CD86, ICAM-1, TNFRII, and GMCSFR were compared between three cohorts: patients with intracranial glioblastoma (n = 15), patients with intracranial metastases (n = 9), and a group of healthy controls (n = 10).

Ventriculoperitoneal shunting of idiopathic normal pressure hydrocephalus increases midbrain size: a potential mechanism for gait improvement.

Objective: Idiopathic normal pressure hydrocephalus (INPH) is characterized by a classic clinical triad of symptoms, including dementia, urinary incontinence, and gait disturbance. Recent work has demonstrated that the maximal midbrain anteroposterior (AP) diameter is significantly smaller in patients with INPH than in healthy, age-matched controls. The current study was undertaken to determine the effect of ventriculoperitoneal shunt placement on midbrain dimensions in INPH patients.

Randomized study of paclitaxel and tamoxifen deposition into human brain tumors: implications for the treatment of metastatic brain tumors.

Purpose: Drug resistance in brain tumors is partially mediated by the blood-brain barrier of which a key component is P-glycoprotein, which is highly expressed in cerebral capillaries. Tamoxifen is a nontoxic inhibitor of P-glycoprotein. This trial assessed, in primary and metastatic brain tumors, the differential deposition of paclitaxel and whether tamoxifen could increase paclitaxel deposition.

Critical postcraniotomy cerebrospinal fluid hypovolemia: risk factors and outcome analysis.

Objective: Critical cerebrospinal fluid (CSF) hypovolemia may cause acute postoperative clinical deterioration in aneurysmal subarachnoid hemorrhage patients after craniotomy for microsurgical aneurysm clipping. We sought to identify risk factors for critical CSF hypovolemia and determine this syndrome's effect on clinical outcome.

Methods: Between April 2001 and June 2004 at Columbia University Medical Center, 16 aneurysmal subarachnoid hemorrhage patients were diagnosed with postoperative critical CSF hypovolemia, whereas 151 patients who underwent craniotomy for clipping were not.

Watershed strokes after cardiac surgery: diagnosis, etiology, and outcome.

Background And Purpose: Watershed strokes are more prevalent after cardiac surgery than in other stroke populations, but their mechanism in this setting is not understood. We investigated the role of intraoperative blood pressure in the development of watershed strokes and used MRI to evaluate diagnosis and outcomes associated with this stroke subtype.

Methods: From 1998 to 2003 we studied 98 patients with clinical stroke after cardiac surgery who underwent MRI with diffusion-weighted imaging.

A technique for minimally altering anatomically based subthalamic electrode targeting by microelectrode recording.

Object: Implantation of a subthalamic nucleus (STN) deep brain stimulation (DBS) electrode is increasingly recognized as an effective treatment for advanced Parkinson disease (PD). Despite widespread use of microelectrode recording (MER) to delineate the boundaries of the STN prior to stimulator implantation, it remains unclear to what extent MER improves the clinical efficacy of this procedure. In this report, the authors analyze a series of patients who were treated at one surgical center to determine to what degree final electrode placement was altered, based on readings obtained with MER, from the calculated anatomical target.

Spinal cord endoplasmic reticulum stress associated with a microsomal accumulation of mutant superoxide dismutase-1 in an ALS model.

Mutation in superoxide dismutase-1 (SOD1), which is a cause of ALS, alters the folding patterns of this protein. Accumulation of misfolded mutant SOD1 might activate endoplasmic reticulum (ER) stress pathways. Here we show that transgenic mice expressing ALS-linked SOD1 mutants exhibit molecular alterations indicative of a recruitment of ER's signaling machinery.

Cognitive and neurobehavioral dysfunction after cardiac bypass procedures.

From a cognitive standpoint, CABG as currently practiced appears to be safe for the great majority of patients, but transient changes involving memory, executive functions, and motor speed may still occur in a subset of patients during the first few days to weeks after CABG. The etiology most likely is multifactorial and includes a synergistic effect of microemboli, hypo-perfusion, and other variables associated with major surgery. Older age and degree of pre-existing cerebrovascular disease have been identified as important risk factors.

Tamoxifen paradoxically decreases paclitaxel deposition into cerebrospinal fluid of brain tumor patients.

Background: P-glycoprotein (Pgp) mediates, in part, resistance to natural product chemotherapy drugs which constitute over half of the available drugs for cancer treatment. Tamoxifen (TAM) enhances intracellular deposition of natural product chemotherapy in human cell lines by inhibition of Pgp. Pgp is highly expressed in the choroid plexus and is thought to be a key component of the blood-cerebrospinal fluid barrier (BCSFB).