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Biomedical subjects

J H Goodman

Publications and source records attributed to J H Goodman.

At least 19 recordsLinked to original sources
PubMed1992

Evidence for commissurally projecting parvalbumin-immunoreactive basket cells in the dentate gyrus of the rat.

The fluorescent retrograde tracer, fluorogold, was used to identify commissurally projecting neurons in the hippocampus and dentate gyrus. After injection of fluorogold into the hippocampus, the contralateral hippocampus was evaluated for fluorogold-immunoreactive or fluorescent neurons. In addition to observing labeled hilar neurons and CA3 pyramidal cells that previously have been reported to send commissurally projecting axons to the contralateral hippocampus, the authors unexpectedly found a population of fluorogold-labeled cells in the granule cell layer with the morphology and location of GABA-immunoreactive basket cells. Immunocytochemical staining revealed that all fluorogold-labeled cells of the granule cell layer were immunoreactive for parvalbumin. However, not all parvalbumin cells, shown previously to be a subset of GABA neurons, were fluorogold-labeled. The association between fluorogold transport and parvalbumin immunoreactivity was unique for these cells of the granule cell layer. In the adjacent hilus, relatively few of the many fluorogold-labeled cells were parvalbumin- or GABA-immunoreactive. These results (1) identify a population of presumed inhibitory neurons that apparently form commissural projections; (2) document that all of these cells contain the calcium-binding protein parvalbumin; and (3) indicate that the vast majority of commissurally projecting hilar neurons are neither parvalbumin- nor GABA-immunoreactive.

Animals↗
PubMed1992

Maxillary removal and reinsertion for improved access to anterior cranial base tumors.

Portions or all of the maxillae are oftentimes removed solely to provide access to certain cranial base tumors rather than because they are involved directly with disease. The purpose of this report is to describe an approach that involves removal of one or both maxillae to improve tumor exposure with subsequent reinsertion as free bone grafts which are stabilized with titanium craniofacial fixation plates. The titanium permits postoperative imaging studies and radiotherapy. Eleven patients ranging from 10 to 69 years of age have undergone 12 operations using this technique for resection of 4 benign and 8 malignant tumors at The Ohio State University. Seven of the 8 patients with malignancies underwent postoperative radiation therapy. There have been no permanent complications and no evidence of bone resorption in this group after follow-up of up to 15 months.

Adolescent↗
PubMed1990

Boron neutron capture therapy of a rat glioma.

The purpose of the present study was to utilize a well-established rat glioma to evaluate boron neutron capture therapy for the treatment of malignant brain tumors. Boron-10 (10B) is a stable isotope which, when irradiated with thermal neutrons, produces a capture reaction yielding high linear energy transfer particles (10B + 1nth----[11B]----4He(alpha) + 7Li + 2.79 MeV). The F98 tumor is an anaplastic glioma of CD Fischer rat origin with an aggressive biological behavior similar to that of human glioblastoma multiforme. F98 cells were implanted intracerebrally into the caudate nuclei of Fischer rats. Seven to 12 days later the boron-10-enriched polyhedral borane, Na2B12H11SH, was administered intravenously at a dose of 50 mg/kg body weight at varying time intervals ranging from 3 to 23.5 hours before neutron irradiation. Pharmacokinetic studies revealed blood 10B values ranging from 0.33 to 10.5 micrograms/ml depending upon the time after administration, a T1/2 of 6.2 hours, normal brain 10B concentrations of 0.5 microgram/g, and tumor values ranging from 1.1 to 12.8 micrograms/g. No therapeutic gain was seen if the capture agent was given at 3 or 6 hours before irradiation with 4 x 10(12) n/cm2 (10 MW-min; 429 cGy). A 13.5-hour preirradiation interval resulted in a mean survival of 37.8 days (P less than 0.01), compared to 30.5 days (P less than 0.03) for irradiated controls and 22.1 days for untreated animals.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Inhibition of tumor growth in a glioma model treated with boron neutron capture therapy.

This investigation attempts to determine whether increased survival time seen when the F98 glioma model is treated with boron neutron capture therapy (BNCT) is a result of inhibition of tumor growth caused by radiation-induced alterations in endothelial cells and normal tissue components. This indirect effect of radiation has been called the tumor bed effect. A series of tumor-bearing rats was studied, using a standardized investigational BNCT protocol consisting of 50 mg/kg of Na2B12H11SH injected intravenously 14 to 17 hours before neutron irradiation at 4 x 10(12) n/cm2. Ten rats, serving as controls, received no treatment either before or after tumor implantation. A second group of 10 rats was treated with BNCT 4 days before tumor implantation; these animals received no further treatment. The remaining group of 10 rats received no pretreatment but was treated with BNCT 10 days after implantation. Histological and ultrastructural analyses were performed in 2 animals from each group 17 days after implantation. Survival times of the untreated control animals (mean, 25.8 days) did not differ statistically from the survival times of the rats in the pretreated group (mean, 25.5 days). The rats treated with BNCT after implantation survived significantly longer (P less than 0.02; mean, 33.2 days) than the controls and the preirradiated animals. Tumor size indices calculated from measurements taken at the time of death were similar in all groups. These results indicate that, with this tumor model, BNCT does not cause a tumor bed effect in cerebral tissue. The therapeutic gains observed with BNCT result from direct effects on tumor cells or on the peritumoral neovascularity.

Animals↗
PubMed1990

Theoretical basis and clinical methodology for stereotactic interstitial brain tumor irradiation using iododeoxyuridine as a radiation sensitizer and 145Sm as a brachytherapy source.

A technique to produce radiation enhancement during interstitial brain tumor irradiation by using a radiation sensitizer (iododeoxyuridine-IdUrd) and by stimulation of Auger electron cascades through absorption of low-energy photons in iodine is described. Clinical studies using iododeoxyuridine, 192Ir as a brachytherapy source, and external radiation have produced promising results. Substituting 145Sm for 192Ir in this protocol is planned to evaluate the enhanced dose resulting from photon activation therapy.

Brachytherapy↗
PubMed1989

Pre-clinical studies on boron neutron capture therapy.

The present report provides an overview of the multidisciplinary research effort on BNCT that currently is in progress at The Ohio State University. Areas under investigation include the preparation of boron containing monoclonal antibodies, the synthesis of boron containing derivatives of promazines and phathalocyanines, the development of a rat model for the treatment of glioblastoma by means of BNCT, the design of an accelerator-based neutron irradiation facility, and 10B concentration measurements using alpha track autoradiographic methods. Progress in each of these areas is described and the direction of future research is indicated.

Animals↗
PubMed1989

Ultrastructural microvascular response to boron neutron capture therapy in an experimental model.

A CD 344 rat glioma model currently used to investigate boron neutron capture therapy (BNCT) was used to demonstrate an increased survival rate after thermal neutron irradiation enhanced by administration of 10B-enriched polyhedral borane, Na2B12H11SH. To investigate the possible effects of BNCT on normal and tumor microvasculature, we subjected animals to sublethal neutron irradiation with and without intravenous injection of 50 mg/kg of enriched 10B and performed histological and ultrastructural analyses. In the rats that did not undergo tumor transplantation, minimal detectable morphological changes in the microvasculature of the central nervous system were observed after treatment, both in the immediate posttreatment phase and at 10 months. Light microscopy of cerebral cortex and caudate nucleus showed normal cytoarchitecture with no evidence of vessel occlusion, hyalinization, thickening, or reactive gliosis. Electron microscopy demonstrated that the junctional complexes of the endothelial cells, the basal lamina, and the perivascular glia were comparable in both treated and control animals. In those animals examined at 18 months, pathological membrane-bound clusters of electron-dense vesicles were seen in pericytes. In the rats implanted with gliomas, vascular proliferation with evidence of breakdown of the blood-brain barrier and vasogenic edema occurred. In the irradiated animals, we noted increased peritumoral edema 3 days after treatment. At seven days, both increased peritumoral edema and necrosis were noted in the rats treated with BNCT. These observations show that the normal microvasculature of the central nervous system tolerates BNCT at the treatment parameters used in our experimental model; the progressive edema and necrosis found in the peritumoral region after BNCT indicate a pathological endothelial response.

Animals↗
PubMed1988

Endurance of the kindling effect is independent of the degree of generalization.

The endurance of the effect of amygdaloid kindling was studied in rats kindled to stages 1-4, then left unstimulated for 45 days prior to resumption of kindling. Afterdischarge duration and behavioral stages upon resumption of kindling revealed retention of the full kindling effect. Endurance of the localized effect of kindling appears to be independent of the degree of generalization prior to interruption of kindling.

Amygdala↗
PubMed1987

Interactive computer graphic image analysis for functional neurosurgery.

This study deals with the use of microcomputer graphic analysis of preoperative magnetic resonance imaging (MRI) scans in functional neurosurgical procedures. Three patients (2 treated for thalamotomy and 1 for thalamic stimulation) had preadmission MRI scans which delineated the classic internal landmarks used in functional neurosurgery. These data were then manipulated and stored using a microcomputer-based graphic analysis system. Intraoperative pattern matching of preadmission graphics with the intraoperative skull X-rays allowed determination of the planned target in the x, y and z coordinates. The accuracy of the graphics FM-PC and AC-PC points was confirmed with the use of ventriculography, stimulation, and postoperative MRI scans. This simple, inexpensive method obviates the need for ventriculography, sedation, intraoperative MRI with a scan-compatible frame, and has the accuracy necessary for functional procedures.

Aged↗
PubMed1987

Microcomputer stereotactic atlas.

A stereotactic atlas to determine thalamic target sites has been incorporated into a microcomputer. Variability studies of the thalamus with mean and standard deviations of nuclear borders are depicted graphically for overlay onto operative images. Internal landmarks traditionally used to reference target points for functional stereotaxis may be determined by conventional ventriculography or derived from magnetic resonance scans. Modeling of polyline vertices established from gray scale contour mapping and atlas reconstructions further enhance the spatial understanding of relationships to midline structures. Computer integration of anatomic reference points, graphically depicted images and stereotactic atlas data into head frame coordinates can be accomplished. This method is consistent with established stereotactic techniques and allows the visual conceptualization of imaged and graphic data for functional stereotaxis.

Brain↗
PubMed1987

Single-scan stereotactic tumor biopsy and brachytherapy.

Stereotactic tumor biopsy and brachytherapy catheter implantation can be accomplished with targets derived from computed axial tomography and magnetic resonance scans. Computer manipulation of image data allows both diagnostic and therapeutic procedures to be carried out from a single set of scan slices. This eliminates the need for repeat scanning as part of the surgical procedure. Microcomputer technology is sufficiently advanced to handle the images and graphics necessary for stereotactic neurosurgery. A system based on the IBM PC/AT designed for this purpose uses readily available graphics software and custom-designed imaging programs. Direct loading of computed axial or magnetic resonance scan images from magnetic tape can be accomplished. Determination of points, contours and volumes in three-dimensional space allows intraoperative alignment of image data and patient landmarks within the stereotactic head frame using pattern recognition overlays. Three-axis scaling for magnification correction along with rotational and linear data transformations provide the basis for single-scan stereotaxis. Interactive computer graphics integrate image, patient and frame coordinates for target determination. This method eliminates the need to design and fabricate nonmagnetic or radiolucent scanner-compatible devices.

Biopsy↗
PubMed1985

Methylprednisolone and neurological function 1 year after spinal cord injury. Results of the National Acute Spinal Cord Injury Study.

A multi-center double-blind randomized clinical trial was conducted by the National Acute Spinal Cord Injury Study Group to examine the efficacy of high-dose methylprednisolone (1000-mg bolus and 1000 mg daily thereafter for 10 days) compared with that of a standard dose (100-mg bolus and 100 mg daily for 10 days). No significant difference was observed in neurological recovery of motor function, pinprick response, or touch sensation 1 year after injury between the two treatment groups, after adjustment for other potentially confounding factors. Analyses that specifically took into account the patients' total steroid dose and relative weight confirmed the lack of a steroid treatment effect. The case fatality rate was 10.7% during the 1st year after injury, and this was not associated with the steroid treatment protocol or the patient's gender. Deaths did occur significantly more frequently among patients who were completely (15.3%) and partially (8.6%) plegic than among those who were paretic (2.5%, p = 0.0005), and among patients aged 50 years or older (38.6%, p = 0.0001).

Clinical Trials as Topic↗
PubMed1979

Platelet aggregation in experimental spinal cord injury. Ultrastructural observations.

Endothelial alterations occur as early as 1 1/2 minutes following impact injury to the primate spinal cord. Separation of the endothelial junctions and exposure of microvascular basal lamina result in platelet adhesion and aggregations that cover defects in the vessel wall and may progress to complete vascular occlusion. This occurs during the first six hours following injury. Platelets also adhere to the surface of damaged endothelium. Hemostasis resulting from platelet thrombus formation is responsible in part for decreased blood flow in the central gray matter following spinal cord trauma.

Animals↗
PubMed1976

Ultrastructural blood-brain barrier alterations and edema formation in acute spinal cord trauma.

Endothelial changes leading to edema formation are examined in the primate spinal cord (Macaca mulatta) following a lesion created by a 20-gm weight falling 15 cm onto the exposed dura. Intravascular perfusion of a paraformaldehydeglutaraldehyde solution followed by carbon black provides adequate fixation of vascular structures and glial elements. Myelin is poorly preserved. Ultrastructural alterations of the blood-brain barrier consist of loss of integrity of the endothelial tight junctions. Edema caused by vascular disruption and parenchymatous extravasation of intravascular contents is observed along with glial swelling. Interglial gap junctions persist in areas of marked cellular seperation and do not impede the migration of edema fluid.

Animals↗