bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hypermetabolism in the acute stage of hemorrhagic cerebrovascular disease
Authors: Touho Hajime , Karasawa Jun , Shishido Hisashi , Morisako Toshitaka , Yamada Keisuke , Shibamoto Keiji 
Published: May 2009

✓ Oxygen consumption carbon dioxide production , urinary nitrogen excretion, respiratory quotient, resting energy expenditure (REE), %REE, and the consumption rates of carbohydrate, fat, and protein (%CHO, %Fat, %Prot, respectively) were determined pre- and postoperatively by indirect calorimetry in 13 patients with ruptured intracranial aneurysms and 11 patients with hypertensive intracerebral hemorrhage in the acute stage. The preoperative urinary nitrogen excretion, respiratory quotient, REE, and %REE were, respectively (mean ± standard deviation): 171 ± 46 ml/min, 203 ± 56 ml/min, 10.3 ± 1.7 gm/day, 0.84 ± 0.01, 1397 ± 389 Cal/day, and 129% ± 8%. The values for REE, and %REE were all increased above normal levels. The %Prot was increased to 26.1% ± 9.1%. In the postoperative period, the urinary nitrogen excretion, REE, and %REE significantly increased to: 186 ± 44 ml/min, 229 ± 56 ml/min, 14.8 ± 2.9 gm/day, 1557 ± 384 Cal/day, and 141% ± 21%, respectively. The %Fat and %Prot also increased significantly, but the %CHO significantly decreased. Preoperatively, in the patients with ruptured intracranial aneurysms, there was a greater increase in %Prot in eight patients classified (according to Fischer) as having a Group 3 or 4 subarachnoid hemorrhage (SAH) on computerized tomography than in five patients classified as having a Group 1 or 2 SAH.
In summary, increased metabolic expenditure, especially increased catabolism of protein and fat, is characteristic of accompanying hemorrhagic cerebrovascular disease, and there is an increase in consumption of fat and protein in the postoperative period. Lack of precise knowledge about the cause and consequences of these metabolic responses makes it impossible at present to judge the optimal extent of nutritional replacement. The hypermetabolic state should be taken into consideration when caring for these patients as it may cause weight loss, poor wound healing, and susceptibility to infection.
Reduction in radiation-induced brain injury by use of pentobarbital or lidocaine protection
Authors: Oldfield Edward H. , Friedman Robert , Kinsella Timothy , Moquin Ross , Olson Jeffrey J. , Orr Kathryn , DeLuca Anne Marie 
Published: May 2009

✓ To determine if barbiturates would protect brain at high doses of radiation, survival rates in rats that received whole-brain x-irradiation during pentobarbital- or lidocaine-induced anesthesia were compared with those of control animals that received no medication and of animals anesthetized with ketamine. The animals were shielded so that respiratory and digestive tissues would not be damaged by the radiation. Survival rates in rats that received whole-brain irradiation as a single 7500-rad dose under pentobarbital- or lidocaine-induced anesthesia was increased from between from 0% and 20% to between 45% and 69% over the 40 days of observation compared with the other two groups (p < 0.007). Ketamine anesthesia provided no protection. There were no notable differential effects upon non-neural tissues, suggesting that pentobarbital afforded protection through modulation of ambient neural activity during radiation exposure.
Neural suppression during high-dose cranial irradiation protects brain from acute and early delayed radiation injury. Further development and application of this knowledge may reduce the incidence of radiation toxicity of the central nervous system (CNS) and may permit the safe use of otherwise “unsafe” doses of radiation in patients with CNS neoplasms.
Delayed traumatic intracerebral hematomas: “Spät-Apoplexie”
Authors: Elsner Henry , Rigamonti Daniele , Corradino Gregory , Schlegel Robert , Joslyn John 
Published: May 2009

✓ Two patients who suffered a head trauma experienced sudden clinical deterioration more than 1 week after their injury. The initial computerized tomography (CT) scan demonstrated a small hematoma underlying a depressed skull fracture in one patient and a small interhemispheric subdural hematoma in the other. Both patients had made a complete recovery and follow-up CT scans were normal when clinical deterioration suddenly occurred. Both patients developed a large intracerebral hematoma and underwent emergency evacuation of the mass. The first patient recovered with the exception of a moderate hemiparesis and dysphasia, but the second patient died.
Delayed traumatic intracerebral hematomas have been described in the literature. Since the advent of CT scanning, the incidence of this phenomenon has been estimated as between 1.7% and 7.4% of closed head injuries. In 1891, Otto Bollinger described four patients who suffered head injury, followed days to weeks later by death from an apoplectic event. His criteria for diagnosis of “traumatische Spät-Apoplexie” included the absence of preexisting vascular disease, a definite history of trauma, an asymptomatic interval of at least several days, and an apoplectic episode. These two cases reemphasize the existence of Spät-Apoplexie as a rare clinical condition. In the presence of CT findings of even small traumatic intracerebral or extracerebral hematomas, the possibility of this late complication should be kept in mind.
Diphtheria toxin effects on brain-tumor xenografts
Authors: Wrobel Charles J. , Wright Donald C. , Dedrick Robert L. , Youle Richard J. 
Published: May 2009

✓ A model was developed to determine whether protein-based chemotherapeutic agents can cross the blood-brain barrier and successfully treat brain tumors. The human small-cell lung carcinoma N417D was grown as a solid tumor in the nude rat brain, and diphtheria toxin (DT) was administered intravenously as therapy. Because rat cells lack functional DT receptors and are 1000 to 10,000 times less sensitive to DT than human cells, a therapeutic window exists between the implanted human tumor and the nude rat host. The pharmacokinetic and pharmacodynamic characteristics of DT were defined. Within 6 hours, more than 90% of the initial DT concentration was removed from the blood. The blood-to-tumor transfer constant Ki for DT in small N417D tumors was 0.49 µl/gm-min, one-fourth to one-fifth the reported values for permeability to proteins in other experimental tumor models. Despite the toxin's short plasma half-life and the relatively intact blood-tumor barrier, DT administered intravenously as a single dose significantly extended animal survival. Untreated nude rats developed solid parenchymal tumors and died in 11 to 16 days (median 15 days). When administered at 0.1 µg/animal, DT increased the median survival time to 19 days (p < 0.0016) while 1.0-µg doses extended median survival times to 26.5 days (p < 0.0002). A higher dose of DT (3.0 µg) had no further beneficial effect on survival (26.1 days).
Blood-brain barrier constraints to successful monoclonal antibody-based therapies of brain tumors may have been overestimated since antibody conjugates have plasma half-lives longer than DT, and the permeability of N417D tumors to DT is equal to or less than the permeability of other experimental tumors to large proteins. Recently developed immunotoxins that have the higher potency of DT and a therapeutic window as wide as DT has in this nude rat/human tumor paradigm may be effective in treating brain tumors despite limited blood-tumor permeability.
Risk of late stroke and survival following carotid endarterectomy procedures for symptomatic patients
Authors: Turner Dennis A. , Tracy Jay , Haines Stephen J. 
Published: May 2009

✓ The long-term outcome following carotid endarterectomy for neurological symptoms was analyzed using a retrospective life-table approach in 212 patients who had undergone 243 endarterectomy procedures. The postoperative follow-up period averaged 38.9 ± 2.1 months (mean ± standard error of the mean). The endpoints of stroke and death were evaluated in these patients. Patient groups with the preoperative symptoms of amaurosis fugax, transient ischemic attack, and prior recovered stroke were similar in terms of life-table outcome over the follow-up period. Sixty-two percent of symptomatic patients were alive and free of stroke at 5 years. The late risk of stroke (after 30 days postoperatively) averaged 1.7% per year based on a linear approximation to the hazard at each life-table interval (1.3% per year for ipsilateral stroke). The trend of late stroke risk was clearly downward, however, and could be fitted more accurately by an exponential decay function with a half-life of 33 months. Thus, the risk of stroke following carotid endarterectomy for neurological symptoms was highest in the perioperative period, slowly declined with time, and occurred predominantly ipsilateral to the procedure.
The definition of a prospective medical control group remains crucial for a critical analysis of treatment modalities following the onset of premonitory neurological symptoms. In the absence of an adequate control group for this series, the calculated perioperative and postoperative stroke risk from this study was compared to data obtained from the literature on stroke risk in medically treated symptomatic patients. This uncontrolled comparison of treatment modalities suggests the combined perioperative and postoperative stroke risk associated with carotid endarterectomy to be modestly improved over medical treatment alone.
Chronic subdural hematoma in infancy
Authors: Aoki Nobuhiko 
Published: May 2009

✓ The cases of 30 infants with chronic subdural hematoma treated surgically between 1978 and 1987 (after the introduction of computerized tomography) were reviewed. This series was limited to infants presenting with increased intracranial pressure, neurological deficits, or developmental retardation. Nineteen patients were male and 11 were female, ranging in age from 1 to 14 months (average 6.1 months). The surgical treatment was initiated with percutaneous subdural tapping which was repeated periodically, if indicated, for 2 weeks. If the patients failed to respond to subdural tapping, subdural-peritoneal shunting was installed. The follow-up periods were from 3 months to 9 years 8 months (average 4 years 10 months). Computerized tomography at that time disclosed disappearance or minimal collection of subdural fluid in 28 cases (93%) and a significant collection (> 5 mm) in two (7%). Neurological examination revealed that the patients were “normal” in 17 cases (57%), “mildly or moderately disabled” in nine (30%), and “severely disabled” in four (13%). The majority of disabled patients had lesions secondary to infantile acute subdural hematoma, child abuse, or hemorrhagic diathesis.
These results indicate that the treatment protocol in the present series is acceptable for the elimination of subdural hematoma. Together, early diagnosis and treatment of the etiological conditions causing the lesion are indispensable for obtaining a satisfactory neurological outcome.
Platelet-activating factor and progressive brain damage following focal brain injury
Authors: Frerichs Kai U. , Lindsberg Perttu J. , Hallenbeck John M. , Feuerstein Giora Z. 
Published: May 2009

✓ The effects of a platelet-activating factor (PAF) antagonist on brain edema, cortical microcirculation, blood-brain barrier (BBB) disruption, and neuronal death following focal brain injury are reported. A neodymium:yttrium-aluminum-garnet (Nd:YAG) laser was used to induce highly reproducible focal cortical lesions in anesthetized rats. Secondary brain damage in this model was characterized by progressive cortical hypoperfusion, edema, and BBB disruption in the vicinity of the hemispheroid lesion occurring acutely after injury. The histopathological evolution was followed for up to 4 days. Neuronal damage in the cortex and the hippocampus (CA-1) was assessed quantitatively, revealing secondary and progressive loss of neuronal tissue within the first 24 hours following injury.
Pretreatment with the PAF antagonist BN 50739 ameliorated the severe hypoperfusion in 12 rats (increasing local cerebral blood flow from a mean ± standard error of the mean of 40.5% ± 8.3% to 80.2% ± 7.8%, p < 0.01) and reduced edema by 70% in 10 rats (p < 0.05) acutely after injury. The PAF antagonist also reduced the progression of neuronal damage in the cortex and the CA-1 hippocampal neurons (decrease of neuronal death from 88.0% ± 3.9% to 49.8% ± 4.2% at 24 hours in the cortex and from 40.2 ± 5.0% to 13.2% ± 2.1% in the hippocampus in 30 rats; p < 0.05).
This study provides evidence to support progressive brain damage following focal brain injury, associated with secondary loss of neuronal cells. In this latter process, PAF antagonists may provide significant therapeutic protection in arresting secondary brain damage following cerebral ischemia and neurological trauma.
NGF-like trophic support from peripheral nerve for grafted rhesus adrenal chromaffin cells
Authors: Kordower Jeffrey H. , Fiandaca Massimo S. , Notter Mary F. D. , Hansen John T. , Gash Don M. 
Published: May 2009

✓ Autopsy results on patients and corresponding studies in nonhuman primates have revealed that autografts of adrenal medulla into the striatum, used as a treatment for Parkinson's disease, do not survive well. Because adrenal chromaffin cell viability may be limited by the low levels of available nerve growth factor (NGF) in the striatum, the present study was conducted to determine if transected peripheral nerve segments could provide sufficient levels of NGF to enhance chromaffin cell survival in vitro and in vivo.
Aged female rhesus monkeys, rendered hemiparkinsonian by the drug MPTP (n-methyl-4-phenyl-1,2,3,6 tetrahydropyridine), received autografts into the striatum using a stereotactic approach, of either sural nerve or adrenal medulla, or cografts of adrenal medulla and sural nerve (three animals in each group). Cell cultures were established from tissue not used in the grafts. Adrenal chromaffin cells either cocultured with sural nerve segments or exposed to exogenous NGF differentiated into a neuronal phenotype. Chromaffin cell survival, when cografted with sural nerve into the striatum, was enhanced four- to eightfold from between 8000 and 18,000 surviving cells in grafts of adrenal tissue only up to 67,000 surviving chromaffin cells in cografts. In grafts of adrenal tissue only, the implant site consisted of an inflammatory focus. Surviving chromaffin cells, which could be identified by both chromogranin A and tyrosine hydroxylase staining, retained their endocrine phenotype.
Cografted chromaffin cells exhibited multipolar neuritic processes and numerous chromaffin granules, and were also immunoreactive for tyrosine hydroxylase and chromogranin A. Blood vessels within the graft were fenestrated, indicating that the blood-brain barrier was not intact. Additionally, cografted chromaffin cells were observed in a postsynaptic relationship with axon terminals from an undetermined but presumably a host origin.
Antiproliferative effect of trapidil, a platelet-derived growth factor antagonist, on a glioma cell line in vitro
Authors: Kuratsu Jun-ichi , Ushio Yukitaka 
Published: May 2009

✓ Platelet-derived growth factor (PDGF) is produced by glioma cells. However, there is heterogeneity among glioma cell lines in the production of PDGF. It has been demonstrated that U251MG cells produce a PDGF-like molecule while U105MG cells do not.
Trapidil, a specific antagonist of PDGF, competes for receptor binding with PDGF. Therefore, the inhibitory effect of trapidil on the proliferation of glioma cells was investigated in vitro using two glioma cell lines. At 100 µg/ml, trapidil significantly inhibited the proliferation of U251MG cells (which produce the PDGF-like molecule). At the same trapidil concentration, the proliferation of U105MG cells (which do not produce the PDGF-like molecule) was not inhibited. The inhibitory effect of trapidil was remarkable on Days 3 and 4 of culture. After 4 days of incubation, the proliferation of U251MG cells was 46% of the control preparation. Trapidil enhanced the antitumor effect of 3-((4-amino-2-methyl-5-pyrimidinyl)ethyl)-1-(2-chloroethyl)-1-nitro-sourea (ACNU) against U251MG cells. The enhancing effect was highest on Days 4 and 6 of culture. After 6 days of incubation in the presence of 100 µg/ml trapidil and 1 µg/ml ACNU, the proliferation of U251MG cells was 18% of the control preparation. These findings suggest that trapidil interrupts the autocrine loop at the PDGF and PDGF-receptor level and that combination therapy with trapidil and ACNU may be useful in the treatment of glioma.
The long-term side effects of radiation therapy for benign brain tumors in adults
Authors: Al-Mefty Ossama , Kersh Jane E. , Routh Anupam , Smith Robert R. 
Published: May 2009

✓ Radiation therapy plays an integral part in managing intracranial tumors. While the risk:benefit ratio is considered acceptable for treating malignant tumors, risks of long-term complications of radiotherapy need thorough assessment in adults treated for benign tumors. Many previously reported delayed complications of radiotherapy can be attributed to inappropriate treatment or to the sensitivity of a developing child's brain to radiation.
Medical records, radiological studies, autopsy findings, and follow-up information were reviewed for 58 adult patients (31 men and 27 women) treated between 1958 and 1987 with radiotherapy for benign intracranial tumors. Patient ages at the time of irradiation ranged from 21 to 87 years (mean 47.7 years). The pathology included 46 pituitary adenomas, five meningiomas, four glomus jugulare tumors, two pineal area tumors, and one craniopharyngioma. Average radiation dosage was 4984 cGy (range 3100 to 7012 cGy), given in an average of 27.2 fractions (range 15 to 45 fractions), over a period averaging 46.6 days. The follow-up period ranged from 3 to 31 years (mean 8.1 years). Findings related to tumor recurrence or surgery were excluded.
Twenty-two patients had complications considered to be delayed side effects of radiotherapy. Two patients had visual deterioration developing 3 and 6 years after treatment; six had pituitary dysfunction; and 17 had varying degrees of parenchymal changes of the brain, occurring mostly in the temporal lobes and relating to the frequent presentation of pituitary tumors (two of these also had pituitary dysfunction). One clival tumor, with the radiographic appearance of a meningioma, developed 30 years post-irradiation for acromegaly. This study unveils considerable delayed sequelae of radiotherapy in a series of adult patients receiving what is considered “safe” treatment for benign brain tumors.
Comparison of crystalloids and colloids for hemodilution in a model of focal cerebral ischemia
Authors: Korosue Kazuyoshi , Heros Roberto C. , Ogilvy Christopher S. , Hyodo Akio , Tu Yong-Kwang , Graichen Robert 
Published: May 2009

✓ Forty dogs were subjected to 6 hours of occlusion of the left internal carotid and middle cerebral arteries. They were divided into two “hemodilution groups” of 13 dogs each and a control “nonhemodiluted group” of 14 dogs. Thirty minutes after arterial occlusion, isovolemic hemodilution was performed by phlebotomy and infusions of low-molecular weight (MW) dextran in one group and of lactated Ringer's solution in the other group. The animals were sacrificed 1 week after temporary arterial occlusion.
Hemodilution reduced the hematocrit to a level of 33% to 34%, which lasted throughout the week in both groups. After hemodilution there was a very significant reduction in blood viscosity, plasma total protein content, and fibrinogen levels in both groups in the acute stage; these levels gradually returned to baseline by the end of the week. In the group with lactated Ringer's solution hemodilution, both osmotic and oncotic pressures were decreased by hemodilution in the acute stage. In the control and low-MW dextran groups, osmotic and oncotic pressure remained unaltered throughout the week. Hemodilution resulted in a slight decrease in mean arterial blood pressure in all groups in the acute stage, but there were no significant changes in central venous, pulmonary arterial, or pulmonary wedge pressures. During the week of study, there were no differences in the cardiac index and total blood volume between the groups, and no significant changes in hematological parameters with the exception of a slight increase in bleeding time immediately after hemodilution with low-MW dextran.
Daily neurological assessment showed consistently poorer condition during the first 5 days in the group with lactated Ringer's solution compared to either the control group or the group receiving low-MW dextran. Based on Mann-Whitney U-testing, the infarct volume of the lactated Ringer's solution recipients, expressed as a percentage of the total volume of that hemisphere (median 15.7%, range 6.6% to 25.2%) was significantly larger than that of the group receiving low-MW dextran (median 2.2%, range 0% to 15.8%) and that of the control group (median 11.9%, range 0% to 39.9%). The results indicate that, in this model, hemodilution with colloids was beneficial, whereas hemodilution with crystalloids was deleterious. It is likely that the decrease in oncotic pressure observed after hemodilution with lactated Ringer's solution is one of the most important reasons for its detrimental effect.
A new 1.9-µ wavelength laser for neurosurgery
Authors: Steichen John D. , Stewart Robert B. , Louis David N. , Choi Benjamin B. , Kung Robert , Martuza Robert L. 
Published: May 2009

✓ The 1.9-µ wavelength component of a 1.9/1.06-µ two-wavelength laser with near-continuous wave properties was tested for its potential use in neurosurgery. The 1.9-µ wavelength has tissue-ablative capabilities, while the 1.06-µ wavelength (Nd:YAG) is suitable for achieving hemostasis. The advantages of the 1.9-µ wavelength over the CO2 laser include its ability to transmit through silica fiberoptic delivery systems and its deeper penetration in water (approximately 100 µ, a depth 10 times greater than for the CO2 laser), which is compatible with irrigation during ablation.
To test the effectiveness of the laser, bilateral craniotomies were performed in anesthetized rats immobilized in a stereotactic frame. Under an operating microscope, lesions were made on the cortex by delivering the 1.9-µ laser beam through a 400-µ fiber at an average power of 1 W over a range of fluences. Subjective intraoperative observations were notable for minimal bleeding, absence of charring when the tissue was irrigated with a thin stream of saline, and uniform lesion formation. For comparison, lesions were generated with a commercially available continuous-wave CO2 laser at equivalent power and fluences. Histological specimens were divided into three groups based on the study after laser application: acute (30 minutes), subacute (48 hours), and chronic (14 days). The extent of thermal injury for the 1.9-µ laser in the acute lesions was quantitatively and histologically similar to that generated by the CO2 laser. Regions of injury extended approximately from the apex of the lesion, and crater depths generated by both lasers were similar (250 to 750 µ) in the range of fluences investigated (1.25 to 10 kJ/sq cm). Subacute and chronic histological specimens demonstrated inflammatory and repair responses that correlated with the acute injury regions in both the 1.9-µ and CO2 laser-treated specimens.
This study demonstrates a neurosurgical potential for a new two-wavelength laser that ablates tissue effectively with limited thermal injury. The 1.9-µ laser is comparable to the widely used CO2 laser but offers several unique advantages, including the ability for delivery through a fiberoptic system and to irrigate tissue during use.