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Purpose: Cerebral metastases represent the most common type of brain tumors. This study investigated the effects of endogenous endostatin on hematogenous cerebral melanoma metastases. Experimental Design: Murine K1735 melanoma cells were... more
Purpose: Cerebral metastases represent the most common type of brain tumors. This study investigated the effects of endogenous endostatin on hematogenous cerebral melanoma metastases. Experimental Design: Murine K1735 melanoma cells were transfected with the mouse endostatin cDNA. Experimental tumors were induced either by s.c. injection, intracerebral implantation, or via injection into the internal carotid artery to simulate hematogenous metastatic spread. The effects of endostatin expression on tumor incidence, growth pattern, and vascularity were analyzed. Results: In vitro secretion of endostatin by 2.5 × 105 cells within 24 hours was 0.12 ± 0.03 ng, 4.35 ± 0.4, and 1.18 ± 0.7 ng/mL for wild type and two endostatin-transfected K1735 clones termed K1735-endo/2 and K1735-endo/8, respectively. Tumor inhibition in vivo correlated with endogenous endostatin production. Within 25 days, growth of s.c. K1735-endo/2 tumors was <20% compared with wild-type controls. Following intracer...
Research Interests: Immunohistochemistry, Apoptosis, Medicine, Mice, Female, and 6 moreMelanoma, Animals, In Vivo, Transfection, Brain Neoplasms, and Endostatin
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Research Interests: Fluorescence Microscopy, Biology, Gene Therapy, Cancer Research, Medicine, and 15 moreBrain Tumor, Neural stem cell, Cell therapy, Humans, Animals, Polymerase Chain Reaction, Long Range, Neoplasia, Cell Transplantation, Neurons, Clinical Sciences, Delivery System, Growth Factor, Enzyme Linked Immunosorbent Assay, and Brain Neoplasms
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✓ Cerebral blood vessels are devoid of vasa vasorum. Therefore, the authors have studied the microarchitecture of the adventitia of large feline cerebral vessels and systemic vessels of the same size, in an effort to determine how the... more
✓ Cerebral blood vessels are devoid of vasa vasorum. Therefore, the authors have studied the microarchitecture of the adventitia of large feline cerebral vessels and systemic vessels of the same size, in an effort to determine how the vessels are nourished. The cerebral vessels contain a rete vasorum in the adventitia that is permeable to large proteins and is in continuity with the subarachnoid space. This substructure may be analogous to the systemic vasa vasorum and may contribute to the nutrition of the cerebral arteries.
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ABSTRACT
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The experiments described herein use an in vitro preparation of choroid plexus to demonstrate that it is a vasopressin-responsive organ by morphologic criteria. Choroid plexus from rats was incubated for one hour in graded concentrations... more
The experiments described herein use an in vitro preparation of choroid plexus to demonstrate that it is a vasopressin-responsive organ by morphologic criteria. Choroid plexus from rats was incubated for one hour in graded concentrations of arginine vasopressin (AVP). Within physiologic range of molar concentration, incubation in vasopressin induced a decrease in basal and lateral spaces in choroid plexus epithelial cells as well as an increase in number of dark cells. The number of cells with basal spaces decreased significantly from 82.7 +/- 9.2 in control tissue to 19 +/- 18 in tissue incubated in 10(-12) M AVP; similarly, the number with lateral cellular spaces decreased from 20 +/- 8.8 to 7.6 +/- 2.2 cells in 10(-10) M AVP. Dark cells increased in number from 3.8 +/- 2.6 in control conditions to 49 +/- 4 with 10(-9) M vasopressin. These data suggest important effects of arginine vasopressin in cerebrospinal fluid (CSF) on choroid plexus, compatible with enhanced fluid transport across choroid epithelial cells.
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A unique characteristic of neural stem cells is their capacity to track glioma cells that have migrated away from the main tumor mass into the normal brain parenchyma. PEX, a naturally occurring fragment of human metalloproteinase-2, acts... more
A unique characteristic of neural stem cells is their capacity to track glioma cells that have migrated away from the main tumor mass into the normal brain parenchyma. PEX, a naturally occurring fragment of human metalloproteinase-2, acts as an inhibitor of glioma and endothelial cell proliferation, migration, and angiogenesis. In the present study, we evaluated the antitumor activity of PEX-producing human neural stem cells against malignant glioma. The HB1.F3 cell line (immortalized human neural stem cell) was transfected by a pTracer vector with PEX. The retention of the antiproliferative activity and migratory ability of PEX-producing HB1.F3 cells (HB1.F3-PEX) was confirmed in vitro. For the in vivo studies, DiI-labeled HB1.F3-PEX cells were stereotactically injected into established glioma tumor in nude mice. Tumor size was subsequently measured by magnetic resonance imaging and at the termination of the studies by histologic analysis including tumor volume, microvessel density...
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Relatively few studies have examined glioma risk in relation to history of cancer in first-degree relatives. We sought to describe such risks in a large hospital-based case-control study. Histologically confirmed incident adult glioma... more
Relatively few studies have examined glioma risk in relation to history of cancer in first-degree relatives. We sought to describe such risks in a large hospital-based case-control study. Histologically confirmed incident adult glioma cases (n = 489) were identified at three regional referral hospitals between June 1994 and August 1998. Controls (n = 799) admitted to the same hospitals for nonmalignant conditions were frequency-matched on age, sex, race/ethnicity, hospital, and proximity of residence to hospital. Participants received a personal interview, including questions regarding cancer in family members. Odds ratios (ORs) were calculated to estimate the risk of glioma associated with a history of cancer in a first-degree relative using conditional logistic regression and compared with standardized incidence ratios among relatives of cases versus relatives of controls. Among participants reporting a family history of a brain cancer or a brain tumor, risk of glioma was 1.6 [95%...
Research Interests: Incidence Geometry, Cancer, Adolescent, Medicine, Family history, and 15 moreHumans, Internal Medicine, Glioma, Female, Male, First Degree Relatives, Confidence intervals, Incidence, Aged, Adult, Logistic Models, Brain Neoplasms, Confidence Interval, Case Control Studies, and Medical and Health Sciences
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OBJECTIVE This work evaluated the clinical feasibility of transcranial magnetic resonance imaging–guided focused ultrasound surgery. METHODS Transcranial magnetic resonance imaging–guided focused ultrasound surgery offers a potential... more
OBJECTIVE This work evaluated the clinical feasibility of transcranial magnetic resonance imaging–guided focused ultrasound surgery. METHODS Transcranial magnetic resonance imaging–guided focused ultrasound surgery offers a potential noninvasive alternative to surgical resection. The method combines a hemispherical phased-array transducer and patient-specific treatment planning based on acoustic models with feedback control based on magnetic resonance temperature imaging to overcome the effects of the cranium and allow for controlled and precise thermal ablation in the brain. In initial trials in 3 glioblastoma patients, multiple focused ultrasound exposures were applied up to the maximum acoustic power available. Offline analysis of the magnetic resonance temperature images evaluated the temperature changes at the focus and brain surface. RESULTS We found that it was possible to focus an ultrasound beam transcranially into the brain and to visualize the heating with magnetic resona...
Research Interests: Surgery, Neurosurgery, Magnetic Resonance Imaging, Treatment, Treatment Outcome, and 15 moreUltrasound, Medicine, Brain Tumor, Humans, Male, Young Adult, Ultrasonic therapy, Focused Ultrasound, Clinical Sciences, Middle Aged, Adult, Nuclear Magnetic Resonance Imaging, Neurosciences, Brain Neoplasms, and Magnetic resonance image
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This experimental study assessed the usefulness of a rat model of corneal angiogenesis for assessing the angiogenic activity of cerebrovascular malformations (CVMs) over time. It is the first investigation to have focused on dynamic... more
This experimental study assessed the usefulness of a rat model of corneal angiogenesis for assessing the angiogenic activity of cerebrovascular malformations (CVMs) over time. It is the first investigation to have focused on dynamic quantification of angiogenesis related to CVMs (i.e., assessing changes over time as opposed to one point in time) and the first to have compared different CVMs and other tissues in this way. The CVM specimens were from 15 randomly selected arteriovenous malformation (AVM) cases, 15 randomly selected cavernous malformation cases, and 2 venous angioma cases. All the samples came from surgical resections performed in the Marmara University Department of Neurosurgery and the Marmara University Institute of Neurological Sciences between January 1998 and January 2003. Glioblastoma multiforme tissues, normal adult brain tissues, and normal brain artery tissues were used as controls. Tissue from each specimen was implanted in one corneal micropocket in each cornea of a single rat, and the level of angiogenic activity in the cornea was graded (low, moderate, or high) at Days 1 through 9 after tissue implantation. Another set of rats was subjected to the same corneal implantation procedure, and two widely accepted indicators of neovascularization, microvessel counts and vascular endothelial growth factor expression, were assessed at Days 3, 5, 7, and 9 after surgery. The tissue-group results for grade of angiogenic activity, microvessel count, and grade of vascular endothelial growth factor expression were compared. Of the three CVM types, the AVMs showed the highest angiogenic activity, cavernous malformations exhibited some degree of angiogenic activity (less than AVMs but more than normal brain artery tissue), and angiogenesis induction by venous angiomas was comparable to that of normal brain artery tissue. Corneas implanted with the AVM samples showed Grade 1 angiogenesis on Day 2, Grade 2 angiogenesis on Day 4, and Grade 2.5 angiogenesis on Day 8. Cavernous malformation samples caused Grade 1 angiogenesis after Day 5, and grading remained less than 1.5. Venous angioma samples resulted in angiogenesis graded less than 1. The results showed that this rat model of corneal angiogenesis is of value for assessing the angiogenic potential of CVMs and for evaluating details of the neovascularization process over time. Further investigation of CVMs with this model might yield information about how angiogenesis can be modulated, and this could lead to development of biological treatments that inhibit this process.
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We have used MR monitoring to guide and evaluate the effects of the Nd:YAG interstitial laser on a well-characterized rat brain tumor model (C6). MRI was used to determine the tumor size, verify the location of the interstitial probe, and... more
We have used MR monitoring to guide and evaluate the effects of the Nd:YAG interstitial laser on a well-characterized rat brain tumor model (C6). MRI was used to determine the tumor size, verify the location of the interstitial probe, and evaluate the size and location of the laser-induced lesion during and after treatment. During laser irradiation, an irreversible loss of signal intensity at the fiber tip and a reversible decrease in signal intensity around it were observed with MRI. None of the treatment protocols affected mean rat survival significantly. Although MRI-guided interstitial laser therapy appears to be safe and easy, it does not provide a curative treatment for spatially disseminated gliomas where a &amp;amp;quot;target volume&amp;amp;quot; cannot be adequately defined. Better results can be expected, especially in well-defined tumors, with improvements of both the imaging techniques and the laser treatment protocol.
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Despite decades of clinical data verifying the success of therapeutic approaches to human pituitary tumors, a significant number of tumors progress and can be life-threatening. The development of better therapeutic strategies for... more
Despite decades of clinical data verifying the success of therapeutic approaches to human pituitary tumors, a significant number of tumors progress and can be life-threatening. The development of better therapeutic strategies for pituitary tumors is complicated by the relative scarcity of human pituitary material for basic experimentation. Human pituitary tissue was used to derive cell cultures, and a cell line, hPIT-1. Molecular and functional analyses were used to further characterize the cells as human pituitary explants in vitro. Functional analyses of the cell cultures indicated that the cells were tumorigenic and of human folliculostellate origin. hPit-1 cells revealed numerous abnormalities of ploidy. Molecular analyses indicated the absence of expression of the following pituitary hormones or hormone subunits by this culture: growth hormone, prolactin, ACTH, FSHbeta, LHbeta, THbeta, and p-glycoprotein. By contrast, the cells expressed uniformly high levels of human follistatin mRNA. Finally, the cells are moderately tumorigenic in immune-deficient mice. Although the precise molecular genetic mechanisms for tumorigenesis in the established cell culture are unknown, the cells serve as a future resource in the study of pituitary tumor initiation, progression, and response to therapy.
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Research Interests: Computer Science, Magnetic Resonance Imaging, Epilepsy, Electroencephalography, Adolescent, and 15 moreMedicine, Brain Mapping, Humans, Child, Computer Systems, Female, Male, Pediatric Neurosurgery, Electrodes, Epilepsy Surgery, Neurosciences, Magnetic resonance image, Postoperative Complications, Child preschool, and Paediatrics and reproductive medicine
Research Interests: Epidemiology, Adolescent, Brain Tumor, Humans, Glioma, and 15 moreMathematical Sciences, Female, Male, Electromagnetic Fields, American, Iron, Electromagnetic Field, Adult, Acoustic Neuroma, Case Control Study, Household Articles, Brain Neoplasms, Confidence Interval, Case Control Studies, and Cumulant
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Epidermoid tumors are benign, slowly growing intracranial masses that still present difficulty in preoperative diagnosis. This article reviews six cases of histologically proven epidermoid tumors. Computed tomography and magnetic... more
Epidermoid tumors are benign, slowly growing intracranial masses that still present difficulty in preoperative diagnosis. This article reviews six cases of histologically proven epidermoid tumors. Computed tomography and magnetic resonance imaging were complementary in their evaluation. Computed tomography demonstrated a hypodense, smoothly contoured extra-axial paramedian mass with lower density than cerebrospinal fluid. Magnetic resonance imaging usually demonstrated an irregularly but sharply marginated mass with inhomogeneous density, variable enhancement with gadolinium, lack of edema in adjacent normal structures, extensive insinuation into cisternal and other cerebrospinal fluid spaces, and a high-signal intensity on proton-weighted images. Multiplanar magnetic resonance imaging was extremely helpful in displaying the full anatomic extent of the lesion and its relationship with other structures.
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The ability to accurately map functional cortex both preoperatively and intraoperatively is an important neurosurgical challenge for the next decade. The central concept of preoperative mapping is to superimpose blood flow and electrical... more
The ability to accurately map functional cortex both preoperatively and intraoperatively is an important neurosurgical challenge for the next decade. The central concept of preoperative mapping is to superimpose blood flow and electrical activation data on a three-dimensional matrix created by MR imaging and image processing. The gold standard, at present, is direct cortical stimulation, which can identify primary motor, sensory, speech, and visual cortices. Cortical mapping can be performed intraoperatively or through implanted subdural electrodes at the bedside. The tasks for the next decade include the validation of these preoperative techniques (fMRI, MEG, TMS, EP): 1. Correlation of direct cortical stimulation with advanced perioperative stimulation/monitoring systems, in a wide variety of cases. In addition, extension of these applications into intraoperative imaging systems like the GE Signa unit should also be envisaged. 2. Evaluation of how various pathologies such as AVMs,...
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Beginning in 1987, selected patients with metastatic brain tumors were treated with permanent implants of low-activity radioactive iodine-125(125I) seeds. These patients underwent craniotomy, gross total resection of the metastatic... more
Beginning in 1987, selected patients with metastatic brain tumors were treated with permanent implants of low-activity radioactive iodine-125(125I) seeds. These patients underwent craniotomy, gross total resection of the metastatic lesion, and placement of the seeds. In general, criteria for treatment included the presence of a recurrent tumor with a volume too large to permit radiosurgery, and a Karnofsky Performance Score of 70 or higher. Thirteen patients underwent 14 implant procedures; all received external whole-brain radiotherapy. Implant dose ranged from 43 Gy to 132 Gy, with a mean of 83 Gy. Survival after implantation ranged from 2 weeks to almost 9 years, with a median of 9 months. Clinical and radiographic local control was obtained in 9 patients. Two patients died of acute, postoperative complications within a month of implantation, so no information regarding tumor control is available for them. Late complications included a bone flap infection in one patient and a CSF...
Research Interests: Brachytherapy, Treatment, Neuro-Oncology, Humans, Iodine, and 10 moreFemale, Male, Neuro, Aged, Middle Aged, Adult, Time Factors, Survival Rate, Neurosciences, and Brain Neoplasms
Gangliogliomas are rare tumors of the central nervous system that account for approximately 1% of all brain tumors. Histologically, gangliogliomas are composed of intimately admixed glial and neuronal components, the pathological origins... more
Gangliogliomas are rare tumors of the central nervous system that account for approximately 1% of all brain tumors. Histologically, gangliogliomas are composed of intimately admixed glial and neuronal components, the pathological origins of which remain to be characterized. Clonal analysis through examination of the pattern of the X chromosome inactivation allows one to distinguish monoclonal differentiation of a genetically abnormal progenitor cell from parallel, but independent, clonal expansion of two different cell types during tumorigenesis in biphasic neoplasms, such as gangliogliomas. In the present study, we investigated the clonality of eight gangliogliomas from female patients using both methylation- and transcription-based clonality assays at the androgen receptor locus (HUMARA) on the X chromosome. Among tumors from seven patients who were heterozygous at the HUMARA locus, five were identified as monoclonal with the methylation-based clonality assay, and the results were...
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This paper initially reviews ligand and receptor systems for the PDGF family and the signalling systems they use as well as their role in neural developments. It then describes the putative role of this family in astrocytoma, meningioma,... more
This paper initially reviews ligand and receptor systems for the PDGF family and the signalling systems they use as well as their role in neural developments. It then describes the putative role of this family in astrocytoma, meningioma, and pituitary adenoma pathogenesis. Potential therapies with receptor antagonists or dominant negative mutants are discussed in the final sections.
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Neurosurgical diagnosis and intervention has evolved through improved neuroimaging, allowing better visualization of anatomy and pathology. This article discusses the various systems that have been designed over the last decade to meet... more
Neurosurgical diagnosis and intervention has evolved through improved neuroimaging, allowing better visualization of anatomy and pathology. This article discusses the various systems that have been designed over the last decade to meet the requirements of neurosurgical patients and opines on the potential future developments in the technology and application of intraoperative MRI. Because the greatest amount of experience with intraoperative MRI comes from its use in brain tumor resection, this article focuses on the origins of intraoperative MRI in relation to this field.
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We used Northern blot analysis to measure the expression of mRNA for platelet-derived growth factor subunit A (PDGF-A), PDGF-B and the PDGF-alpha receptor (PDGFR-alpha) and PDGF-beta receptor (PDGFR-beta) in ependymomas and... more
We used Northern blot analysis to measure the expression of mRNA for platelet-derived growth factor subunit A (PDGF-A), PDGF-B and the PDGF-alpha receptor (PDGFR-alpha) and PDGF-beta receptor (PDGFR-beta) in ependymomas and medulloblastomas. We analyzed tissue from 5 patients for each tumor type, looking specifically for components of an autocrine or paracrine system in these tumors. PDGF-A was expressed in all tumors, PDGFR-alpha, which binds all 3 PDGF isoforms, was only found in ependymomas. Thus only ependymomas appeared to have a potential for using PDGFR-alpha autocrine loops. PDGF-B was expressed only in ependymomas, although the PDGFR-beta was expressed in both medulloblastomas and ependymomas. Again, therefore, only ependymomas appear to have a potential autocrine loop with PDGFR-beta. These data suggest that ependymomas have the biochemical prerequisites for autocrine and/or paracrine loops using PDGFR-alpha or PDGFR-beta systems. In this they resemble other glial tumors such as anaplastic astrocytomas and glioblastomas. Medulloblastomas do not appear to have the ligand and/or receptor for either the PDGFR-alpha or PDGFR-beta autocrine loop.
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Radical resection of low-grade gliomas can decrease the incidence of recurrence, the time to tumor progression, and the incidence of malignant transformation. The authors present a series of 25 patients who underwent craniotomy and... more
Radical resection of low-grade gliomas can decrease the incidence of recurrence, the time to tumor progression, and the incidence of malignant transformation. The authors present a series of 25 patients who underwent craniotomy and resection of low-grade tumor in an intraoperative magnetic resonance (MR) imager. This is an open configuration 0.5-tesla imager developed by The Brigham and Women's Hospital and General Electric, in which a patient can be placed to undergo surgery. Gross-total removal was accomplished under real-time image guidance. These intraoperative images allow definitive localization and targeting of the lesions and accommodate anatomical changes that may occur during surgery. The authors consistently found that the extent of abnormality seen on the intraoperatively obtained films of resection was larger than that apparent in the surgical field of view alone. Intraoperative imaging made accurate surgical identification of these abnormal areas and subsequent res...
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It has been demonstrated that glial fibrillary acidic protein (GFAP)-positive astrocyte precursors will differentiate in response to application of retinoic acid (RA), whereas GFAP/oligodendrocyte type 2-astrocyte progenitors will be... more
It has been demonstrated that glial fibrillary acidic protein (GFAP)-positive astrocyte precursors will differentiate in response to application of retinoic acid (RA), whereas GFAP/oligodendrocyte type 2-astrocyte progenitors will be inhibited from differentiating and continue to be mitotically active in the presence of RA. The authors sought to determine if cells taken from glial tumors that were GFAP positive retained the ability to differentiate following application of RA in vitro, as their normal astrocytic counterparts do. Primary cultures of seven astrocytic tumors were observed to have significantly fewer cells following 1 month of continuous exposure to 100 μM RA. Comparisons with sister control cultures indicated that in control conditions the tumor cells had undergone proliferation, whereas the number of cells in the RA-exposed cultures remained closer to the number of cells initially plated. This response to RA was demonstrated to be specific to the astrocytic tumors by ...
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... Meningioma and NF2: A Review. Hoffman, Caitlin E. * ; Ament, Jared ; Black, Peter MD, PhD . Article Outline. Collapse Box Author Information. ... Rohringer M, Sutherland GR, Louw DF, et al. Incidence and clinicopathological... more
... Meningioma and NF2: A Review. Hoffman, Caitlin E. * ; Ament, Jared ; Black, Peter MD, PhD . Article Outline. Collapse Box Author Information. ... Rohringer M, Sutherland GR, Louw DF, et al. Incidence and clinicopathological features of meningioma. J Neurosurg. ...
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Telomerase activity, which is undetectable in most mature normal tissues, has been identified in many types of human cancers, including neuroblastomas and oligodendrogliomas. These findings suggest that a novel mechanism in addition to... more
Telomerase activity, which is undetectable in most mature normal tissues, has been identified in many types of human cancers, including neuroblastomas and oligodendrogliomas. These findings suggest that a novel mechanism in addition to activation of oncogenes and inactivation of tumor suppressor genes may play an important role in tumorigenesis. The goal of the present study was to assess and correlate the telomerase activity in astrocytic gliomas of different grades. Telomere repeat amplification protocol and Southern blot hybridization with telomere-specific probes were used to detect telomerase activity and to measure terminal restriction fragment length, respectively. Telomerase activity was detected in 3 of 9 (33%) low-grade astrocytomas (World Health Organization Grade II), 5 of 11 (45%) anaplastic astrocytomas (World Health Organization Grade III), 36 of 41 (89%) glioblastomas multiforme (World Health Organization Grade IV), 3 of 4 (75%) oligodendrogliomas, and none of 4 normal brain specimens. We demonstrated that telomerase activity is absent in normal brain tissues while present in most glioma samples (72%). The frequency of such activity increases with malignancy. These results suggest that telomerase activity may be used as a tumor marker and that the activation of telomerase may correlate with initiation and malignant progression of astrocytic tumors.
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Over the last decade, much has been learned about the genetic changes that occur in human neoplasia and how they contribute to the neoplastic state. Oncogenes and tumor suppressor genes have been identified, and many powerful molecular... more
Over the last decade, much has been learned about the genetic changes that occur in human neoplasia and how they contribute to the neoplastic state. Oncogenes and tumor suppressor genes have been identified, and many powerful molecular genetic techniques have emerged. Brain tumors have been intensively studied as part of this process. Specific and recurring genetic alterations have been identified and are associated with specific tumor types. In astrocytomas, for example, losses of genetic material on chromosomes 10 and 17 and amplification of the epidermal growth factor receptor gene seem important in pathogenesis, with the loss of chromosome 10 and the amplification of epidermal growth factor receptor being strongly associated with glioblastoma multiforme. Meningiomas, on the other hand, have usually lost part or all of chromosome 22. Brain tumors also express growth factors and growth factor receptors that may be important in promoting tumor growth and angiogenesis. These include epidermal growth factor, transforming growth factor-alpha, platelet-derived growth factor, the fibroblast growth factors, and vascular endothelial growth factor. In this article, we review the genetic aberrations that occur in the major types of brain tumors, including glial tumors, meningiomas, acoustic neuromas, medulloblastomas, primitive neuroectodermal tumors, and pituitary tumors. Wherever possible, clinical correlations have been made concerning the prognostic and therapeutic implications of specific aberrations. We also provide some background about the cytogenetic and molecular genetic techniques that have contributed to the description and understanding of these alterations and speculate as to some clinical and basic science issues that might be explored in the future.
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The presence of specific steroid hormone-binding receptors has been correlated with the clinical response to hormonal therapy in a number of different neoplasias, including breast and prostate cancer. In this article, we investigated the... more
The presence of specific steroid hormone-binding receptors has been correlated with the clinical response to hormonal therapy in a number of different neoplasias, including breast and prostate cancer. In this article, we investigated the expression of the androgen, estrogen, glucocorticoid, and progesterone receptor messenger ribonucleic acid (mRNA) and protein in a number of astrocytic neoplasms of various histological grades. Androgen and glucocorticoid receptor mRNA were detected in all astrocytic neoplasms examined, regardless of histological subtype. In contrast, progesterone receptor mRNA was observed more frequently in high-grade tumors than in low-grade tumors. Estrogen receptor mRNA was undetectable in all astrocytic tumors examined. These studies suggest a possible adjunct clinical use of hormonal therapy for the treatment of astrocytomas. Specific antagonists and agonists may allow the modulation of the growth of these tumors. Development of this body of knowledge may lead to the development of better treatment for these aggressive tumors.
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Craniotomy and brain mapping performed with the patient under local anesthesia and monitored sedation is an important technique to allow optimal resection of brain tumors or other lesions in close apposition to eloquent cortex. The... more
Craniotomy and brain mapping performed with the patient under local anesthesia and monitored sedation is an important technique to allow optimal resection of brain tumors or other lesions in close apposition to eloquent cortex. The subjective experience of patients undergoing this procedure has not been addressed in the literature. This study formally, intensively, and prospectively assessed the subjective experience of 21 consecutive patients undergoing this procedure. Assessment involved structured interviews at 2 to 3 days postoperatively by a member of the surgical team and at 1 month postoperatively by a psychiatrist, supplemented by pre- and postoperative assessments of the patients&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; moods using the brief Profile of Mood States questionnaire. At the 1-month interview, all patients were entirely comfortable with the experience and there were no indications of adverse psychological sequelae of the event. In the early postoperative interview, approximately one-half of the patients reported that the experience was entirely satisfactory, without any intraoperative discomfort or pain. One-third of the patients recalled minor difficulties at some stage of the experience, and one-fifth recalled moderate difficulties. An operating room score was devised to quantify the data. Minor technical changes are suggested to improve the patients&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; subjective experience. This series confirmed that this technique is a very useful and safe technique for resection of lesions involving eloquent cortex that might otherwise be considered inoperable. This procedure involves a level of stress that remains within the tolerance level of the average adult.
Research Interests: Psychology, Neurosurgery, Affect, Prospective studies, Humans, and 14 moreMale, Patient Satisfaction, Dental Local Anesthesia, Clinical Sciences, Aged, Middle Aged, Questionnaires, Adult, Neurosciences, Conscious Sedation, Postoperative Complications, Craniotomy, Interviews as topic, and Intraoperative complications
✓ Irrigation of the subarachnoid space after aneurysmal subarachnoid hemorrhage (SAH) has been reported to alleviate subsequent arterial vasospasm. The authors have investigated the effect of lavage of the cerebrospinal fluid (CSF) space... more
✓ Irrigation of the subarachnoid space after aneurysmal subarachnoid hemorrhage (SAH) has been reported to alleviate subsequent arterial vasospasm. The authors have investigated the effect of lavage of the cerebrospinal fluid (CSF) space in the two-hemorrhage canine model of vasospasm. Twelve dogs had basilar cistern lavage with 120 cc of artificial CSF 24 hours after each of two SAH's, and 12 control dogs had two sequential SAH's without intervening lavage of clot. The amount of clot on the ventral brain stem was evaluated at sacrifice and was graded from 0 (no clot) to 4 (maximum clot) to assess the adequacy of clot removal. Dogs that had undergone lavage had a median grade of 1 (range Grade 0 to 2); control dogs had a median grade of 2 (range Grade 1 to 3.5, p < 0.001, Wilcoxon rank sum test), indicating significant reduction of gross clot by lavage. The neurological findings were graded from 0 to 5, based on meningismus, ataxia, paresis, and cranial nerve deficits. No...
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✓ The Peter Bent Brigham Hospital was established in Boston in 1913. The purchase of the site defined what would become one of the largest medical complexes in the world. This hospital was intended to be a university hospital based on the... more
✓ The Peter Bent Brigham Hospital was established in Boston in 1913. The purchase of the site defined what would become one of the largest medical complexes in the world. This hospital was intended to be a university hospital based on the model created by Johns Hopkins University. The pioneering work of Harvey Cushing while at the Peter Bent Brigham Hospital is briefly touched on.