bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of subarachnoid hemorrhage on contractile responses and noradrenaline release evoked in cat cerebral arteries by histamine
Authors: Lobato Ramiro D. , Marín Jesús , Salaices Mercedes , Rico Mercedes L. , Sanchez Carlos F. 
Published: May 2009

✓ This study analyzes the changes induced by subarachnoid hemorrhage (SAH) on the contractile responses and the noradrenaline release evoked in cat cerebral arteries by histamine. The dose-dependent vasoconstriction induced by histamine on the cerebral arteries of normal cats was significantly reduced by diphenhydramine and phentolamine. When SAH was produced 3 and 7 days before the experiment, the histamine-induced vasoconstriction also decreased. Thereafter, a tendency to normalization in the contractile vascular responses was observed such that 15 days after the hemorrhage it was not significantly different from that found in control animals. The decrease in the contractile responses to histamine provoked by SAH was similar to that seen after pretreatment with intracisternal injections of 6-hydroxy-dopamine.
The amount of radioactivity released by histamine following preincubation with 3H-noradrenaline from the cerebral arteries of cats exposed to SAH 3, 7, and 15 days before the experiment was significantly reduced when compared with controls. Moreover, the basal level of tritium release and the radioactivity retained at the end of the experiment were also decreased after SAH. These decreases were less marked 15 days after SAH. Intracisternal injections of 6-hydroxydopamine 3, 7, and 15 days prior to the assay, and the removal of both superior cervical ganglia 15 days before the experiment, also markedly reduced these three parameters. These results indicate that histamine releases noradrenaline from cat cerebral arteries, and SAH produces a transient denervation of the perivascular adrenergic nerve endings. The inhibition of the histamine-induced vasoconstriction observed after SAH might be explained by the impairment of the indirect adrenergic mechanism involved in the overall contractile response elicited by this amine in cerebral arteries. According to the present findings, histamine does not seem to play a significant role in the production of the cerebral vasospasm occurring after SAH.
Evaluation of prostaglandin biosynthetic activity in canine basilar artery following subarachnoid injection of blood
Authors: Sasaki Tomio , Murota Sei-itsu , Wakai Susumu , Asano Takao , Sano Keiji 
Published: May 2009

✓ Transformation of arachidonic acid into prostaglandins was investigated in the basilar artery by incubating sections of artery with carbon-14-labeled arachidonic acid. Thin-layer radiochromatography revealed that, in normal canine basilar arteries, 14C-arachidonic acid was transformed mainly to 6-ketoprostaglandin (PG)F1α, a spontaneous metabolite of prostacyclin (PGI2). Among other prostaglandins, only a small amount of PGF2α was detected, whereas PGD2, PGE2, and thromboxane B2 were not. Arteries removed on Days 3 and 8 after subarachnoid blood injection showed a prostaglandin synthesis profile similar to that in the normal cerebral artery.
In borate-buffered saline (0.1M borate buffer, pH 9.0/0.15M NaCl = 1:9, vol/vol), canine basilar artery produced a PGI2-like substance that inhibited adenosine diphosphate (ADP)-induced platelet aggregation. Its anti-aggregatory activity was completely abolished by acidification. Aspirin likewise inhibited production of the anti-aggregatory substance. From these results, it was concluded that the anti-aggregatory activity was due solely to the production of PGI2 by the arterial specimen. Based on the above results, PGI2 biosynthetic activity in the cerebral artery exposed to subarachnoid blood injection was bioassayed by measuring the inhibitory activity of the incubation product upon ADP-induced platelet aggregation following incubation of the arteries in borate-buffered saline for 5 to 30 minutes at 20°C, using synthetic PGI2-Na as a standard.
The synthetic activity of PGI2 in the artery exposed to subarachnoid blood injection had diminished remarkably by Days 3 and 8. This diminution of PGI2 synthesis in the cerebral artery may be involved in the pathogenesis of cerebral vasospasm.
Subarachnoid hemorrhage and cerebrovascular spasm
Authors: Petter Eldevik O. , Kristiansen Kristian , Torvik Ansgar 
Published: May 2009

✓ Artificial subarachnoid hemorrhage (SAH) produced by injection of autologous blood into the cisterna magna in dogs gave rise to considerable narrowing or spasm of the basilar artery and its branches, including the posterior cerebral arteries, as demonstrated by cerebral angiography. Repeated cisternal injections of blood at various intervals produced more severe spasm than a single injection. After perfusion-fixation of the brain, the cerebral arteries were examined by light and electron microscopy. None of the animals showed abnormalities in the intima or media of the vessel walls. Previously reported findings of morphological changes due to spasm could not be confirmed.
Postmortem examination of brain vessels from nine patients with SAH and arterial spasm showed no specific changes that could be ascribed to spasm.
Pineal tumors in children and adolescents
Authors: Abay Eustaquio O. , Laws Edward R. , Grado Gordon L. , Bruckman James E. , Forbes Glenn S. , Gomez Manuel R. , Scott Mark 
Published: May 2009

✓ Tumors of the pineal region account for 3% to 8% of pediatric intracranial tumors. The treatment of such tumors has been in a state of flux between conservative therapy (cerebrospinal fluid shunting and radiotherapy) and direct surgical removal. A brief history and review of the literature with analysis of both approaches is given, and the Mayo Clinic's experience with conservative treatment of tumors in the pineal region in patients 20 years old and younger (27 cases) is studied and analyzed. The series comprises 21 boys and six girls, with an age range of 1 to 20 years (mean 13.7 years). Follow-up examinations are complete and range from 1 to 24 years, with a mean follow-up period of 7.8 years. The median survival time for these patients treated with shunt and radiotherapy is 17.7 years. There was no mortality from treatment and complications were rare. The details of the clinical presentation, diagnostic findings, pathology, therapy, recurrence, and survival are presented.
All patients under 6 years of age (six cases) had recurrences, 50% in other areas in the brain and 50% in the spinal cord, perhaps pointing to the need for whole-brain and spinal-axis irradiation in patients in this age group. The results of this study of the conservative approach form a standard against which results of any other type of therapy may be compared.
Internal irradiation for cystic craniopharyngioma
Authors: Kobayashi Tatsuya , Kageyama Naoki , Ohara Ken 
Published: May 2009

✓ The authors report the results of internal irradiation with labeled chromic phosphate (32P) and gold-198 (198Au) colloid in eight cases of cystic craniopharyngiomas. They used a newly developed dosimetric formula, by which the radiation dose at the cyst wall and at any point far from the radioactive source can be calculated. Ten courses of irradiation in eight patients were carried out by injection of either 32P or 198Au colloid into the cyst through an Ommaya drainage system that had been placed at craniotomy. Follow-up studies ranging from 13 to 156 months revealed that all cysts were effectively treated, with elimination of fluid or collapse of the cyst. This was confirmed by Conray cystography and/or computerized tomography.
Not only the dose delivered to the wall but also the thickness of the cyst wall and the location of the cyst are important factors in planning internal irradiation. A safe and adequate dose to the cyst wall could range between 9000 to 30,000 rads for craniopharyngioma. This treatment is suitable for large cysts that are thought to be difficult to remove radically, recurrent cysts resistant to previous treatment, or multiple cysts. Internal irradiation may also be applicable in other cystic intracranial tumors if dosimetry is calculated accurately.
Reoperation for glioblastoma
Authors: Young Byron , Oldfield Edward H. , Markesbery William R. , Haack Dennis , Tibbs Phillip A. , McCombs Paul , Chin Hong W. , Maruyama Yosh , Meacham William F. 
Published: May 2009

✓ The results of a second operation for tumor removal in 24 adult patients with supratentorial glioblastoma multiforme or anaplastic astrocytoma were analyzed. The median survival time after reoperation was 14 weeks. Five of the 24 patients lived 6 months or longer after reoperation. Only three of these patients maintained a Karnofsky rating (KR) of at least 60 for 6 months or longer after reoperation.
Preoperative neurological status (KR) is the most significant determinant of survival after reoperation (p = 0.02). When the KR is at least 60, median survival after reoperation is 22 weeks. When the KR prior to reoperation is less than 60, median survival is 9 weeks. Only one of 13 patients with a KR of less than 60 prior to reoperation survived longer than 6 months after the second operation. The interval between first and second operation is significantly related to survival (p = 0.03), but when adjustment is made for the KR the interoperative interval is no longer significantly related to survival after the second operation (p = 0.39). Age, sex, and location of tumor were not significantly related to duration of survival.
This study suggests that reoperation is most likely to produce the best result when the KR is at least 60 and the interval between operations is longer than 6 months. Using these criteria, one-third of the patients could be expected to survive with a KR of at least 60 for 6 months. The study indicates that reoperation should not be carried out when the KR is less than 60.
Immunological, biochemical, ultrastructural, and electrophysiological characteristics of a human glioblastoma-derived cell culture line
Authors: Black Peter McL. , Kornblith Paul L. , Davison Peter F. , Liszczak Theodore M. , Merk Linda P. , Smith Barry H. , McKeever Paul E. , Quindlen Eugene A. 
Published: May 2009

✓ This report presents the results of a study using multiple techniques of the established human cell line, LM, which has been developed in culture medium from a patient with a right temporoparietal glioblastoma. This cell line has human subtetraploid karyotype and has several features of a transformed line in culture. These include continuous propagation for 10 years, ability to form tumor nodules when transplanted into immunologically suppressed hamsters, and pleomorphic appearance. Ultrastructurally, it is characterized by multiple nuclei, few actin cables, and numerous surface-membrane microvilli, as well as abundant 9- to 10-nm cystoplasmic filaments. By its immunological reactivity, the line can be shown to contain glial fibrillary acidic protein at low levels, consistent with its glial origin and continued nature. Dibutyryl cyclic adenosine monophosphate (db-cAMP) induces formation of long astrocytic-like processes as well. Its membrane electrical characteristics include a low resting membrane potential and short time constant. Used in a microtiter antiglioma antibody cytotoxicity assay, LM yields a positive reaction to antibodies in the sera of 80% of patients with astrocytomas and only 9% of normal blood-bank donors, suggesting that it shares common antigens with other astrocytic tumor lines.
The varied characteristics of this glioblastoma-derived line emphasize the “multiforme” nature of the neoplasm and suggest that for characterization of any such line, multiple parameters are necessary to allow comparison with other long-term glioblastoma lines in the literature. The usefulness of the LM line in in vitro cell biological, immunological, chemotherapeutic, and radiobiological studies of gliomas makes such efforts very worthwhile.
Intracranial pressure changes following aneurysm rupture
Authors: Voldby Bo , Enevoldsen Erna M. 
Published: May 2009

✓ Intraventricular pressure (IVP) was measured continuously by the method of Lundberg for an average period of 8 days in 52 patients with recent rupture of an intracranial saccular aneurysm. The patients were graded as follows according to the system of Hunt and Hess: 13 patients were Grades I–II, 19 patients Grades II–III, and 20 patients Grades III–V. The degree of cerebral arterial spasm was measured on angiograms taken on admission and approximately 7 days later. Drainage of ventricular cerebrospinal fluid was performed intermittently when IVP exceeded 25 mm Hg.
The results showed a close correlation between changes in clinical grade and in mean IVP. Drainage improved the condition in uncomplicated cases, but was less effective or ineffective when severe vasospasm or rebleeding occurred. Lowering the IVP by drainage did not appear to increase the risk of rebleeding. In contrast to patients with no or slight spasm, patients with severe spasm had a permanently elevated IVP, even before spasm was demonstrable angiographically. A mean IVP exceeding 25 mm Hg for the whole period of monitoring was associated with a poor prognosis. Finally, indications for continuous monitoring of IVP and ventricular drainage in aneurysm patients are suggested.
Cerebral dissecting aneurysm and intimal fibroelastic thickening of cerebral arteries
Authors: Mizutani Tomohiko , Goldberg Herbert I. , Parr Justin , Harper Clive , Thompson Carson J. 
Published: May 2009

✓ A 19-year-old white man developed aphasia and right hemiplegia after several falls while waterskiing. Cerebral angiography displayed a ripple appearance and a “string of beads” sign along the left middle cerebral artery, with occlusion or stenosis of most of its branches. The patient died after 6 days, of transtentorial herniation due to massive left cerebral infarction. At necropsy, the infarct was found to be due to a subintimal dissecting aneurysm of the left middle cerebral artery. Multifocal areas of intimal fibroelastic thickening (IFT) were found not only at the site of dissection, but also in the other cerebral arteries, most prominent at the bifurcations of the vessels.
A systematic study of cerebral arteries performed in six control cases revealed that IFT was present in a similar distribution to that seen in the patient described. However, the degree of IFT in this patient was greater than in the controls. Some individuals with excessive IFT may be more susceptible to cerebral dissecting aneurysm under a variety of stresses, especially trauma.
Transsphenoidal microsurgical removal of growth hormone-secreting pituitary adenomas
Authors: Baskin David S. , Boggan James E. , Wilson Charles B. 
Published: May 2009

✓ A series of 137 patients with growth hormone (GH)-secreting pituitary adenomas were treated by transsphenoidal surgery during a 10-year period. Group A comprised patients for whom this surgery was the first therapeutic intervention, and Group B included those who underwent the surgery after previous therapeutic intervention. The results were analyzed considering preoperative and postoperative endocrinological, neurological, ophthalmological, and neuroradiological data. Remission was defined as clinical response and a normal postoperative GH level, and partial remission as clinical response and postoperative reduction of the GH level by more than 50%. Any other result was considered failure. The mean follow-up period was 37.1 months; follow-up review was achieved in all the patients.
Among the 102 patients in Group A, remission was achieved in 80 (78%) patients with transsphenoidal surgery alone, and in an additional 16 (16%) after postoperative irradiation (combined response rate, 94%). All failures and patients with partial remission had preoperative GH levels of more than 50 ng/ml and suprasellar extension of the tumor. There were no deaths; 8% of patients had minor surgical morbidity; 5% had new hypopituitarism postoperatively. Of patients subsequently irradiated, 71% developed hypopituitarism.
Among the 35 patients in Group B, remission was achieved in 26 (74%), partial remission was obtained in two (6%), and seven (20%) were considered treatment failures. There were no deaths, and the morbidity rate was 14%; 66% of patients had hypopituitarism postoperatively. Of the eight patients who had received prior irradiation only, seven (88%) went into remission. All failures and partial responders had preoperative GH levels greater than 40 ng/ml; 56% had suprasellar extension. These results confirm the efficacy of the transsphenoidal approach for the treatment of GH-secreting pituitary adenomas.
Intracranial pressure: to monitor or not to monitor?
Authors: Narayan Raj K. , Kishore Pulla R. S. , Becker Donald P. , Ward John D. , Enas Gregory G. , Greenberg Richard P. , Da Silva A. Domingues , Lipper Maurice H. , Choi Sung C. , Mayhall C. Glen , Lutz Harry A. , Young Harold F. 
Published: May 2009

✓ The authors have analyzed their experience with intracranial pressure (ICP) monitoring in 207 patients over a 4-year period. Patients with either high-density or low-density lesions on computerized tomography (CT) at admission had a high incidence (53% to 63%) of intracranial hypertension (ICP persistently over 20 mm Hg). In contrast, patients with normal CT scans at admission had a relatively low incidence of ICP elevation (13%). Among these patients, three features were found to be strongly associated with the development of intracranial hypertension: 1) age over 40 years; 2) systolic blood pressure under 90 mm Hg; and 3) motor posturing — unilateral or bilateral. When two or more of these features were noted at admission, the incidence of intracranial hypertension was 60%, as compared to 4% when only one, or none, of these features were present. Thus, the patients at high risk for developing intracranial hypertension after severe head injury are those with abnormal CT scans at admission, and those with normal CT scans who demonstrate two or more of the above-mentioned adverse features. Based on these criteria, only 16% of this series of patients with normal CT scans would have qualified for monitoring.
In addition to the three clinical features noted above, multimodality evoked potential (MEP) studies were also found to be strong predictors of ICP elevation in the normal CT scan group, with a 75% incidence of intracranial hypertension in patients with disseminated deficits. There was no statistically significant correlation between the Glasgow Coma Scale score, eye movements, pupillary reaction, hypoxia, or anemia at admission and subsequent ICP elevation in the group with normal CT scans.
In this series, an intraventricular catheter was used as the sole monitoring device in 91% of the cases. In the remaining 9%, subarachnoid screws were employed, either alone, or upon failure of the ventriculostomy. While no mortality was directly ascribed to the monitoring process, there was a 7.7% complication rate (infection 6.3% + hemorrhage 1.4%). Eighty-five percent of the infections occurred in patients who had been monitored for 5 days or more, while no infections were noted in those monitored for less than 3 days. Used judiciously, this technique can be valuable in the monitoring and treatment of the brain-injured patient.
Posterior circulation revascularization
Authors: Ausman James I. , Diaz Fernando G. , de los Reyes R. A. , Pak Hooshang , Patel Suresh , Mehta Bharat , Boulos Roushdy 
Published: May 2009

✓ Eight patients were evaluated for severe vertebrobasilar insufficiency (VBI). There were five males and three females, with an average age of 60.2 years (range 42 to 67 years). Three were diabetic and five hypertensive, including two patients who had both diseases. Seven of the eight had ongoing episodes of VBI refractory to anticoagulant and/or antiplatelet agents. Symptoms included two or more of the following in all patients: dizziness, diplopia, hemiparesis, hemihypesthesia, perioral numbness, bilateral visual blurring, dysarthria, and ataxia. Angiography revealed severe atherosclerotic stenosis of the proximal or midsection of the basilar artery in all patients.
A 10-cm segment of the anterior or posterior division of the superficial temporal artery (STA) was anastomosed to a proximal segment of the superior cerebellar artery (SCA) through a right subtemporal approach. Seven of eight (87%) postoperative angiograms demonstrated patency as evidenced by filling of the SCA and, in most cases, of the basilar artery. Six of the eight patients were improved or asymptomatic after the operation, one was unchanged, and one died. The average follow-up period was 14 months, with a range of 4 to 23 months. Transient morbidity included temporal lobe swelling in four patients and a subdural hematoma in one. Anastomosis of the STA to the SCA is a feasible therapeutic option in the patient with VBI secondary to stenosis of the proximal or midsection of the basilar artery.
Facial nerve preservation in patients with large acoustic neuromas treated by a combined middle fossa transtentorial translabyrinthine approach
Authors: Tator Charles H. , Nedzelski Julian M. 
Published: May 2009

✓ With large acoustic neuromas, the primary goal of surgery is safe total removal of the tumors, and the secondary goal is preservation of nearby neural structures, including the facial nerve. In a series of 15 consecutive patients with large cerebellopontine angle tumors, all of which were more than 2.5 cm in diameter, tumor excision was performed by a one-stage combined middle fossa-translabyrinthine approach. There were 13 acoustic neuromas, 10 of which were more than 4 cm in diameter, one petrous apex meningioma 4 cm in diameter, and one facial neuroma 3 cm in diameter. The tumors were totally removed in all 15 patients. The facial nerve was preserved in 12 of 13 evaluable patients. In the 14th patient the nerve had been transected in a previous suboccipital procedure with incomplete removal, and in the 15th patient the nerve was sutured following excision of a facial neuroma. Thus, the nerve was lost at surgery in only one patient.
This combined approach provided very clear visualization of the cerebellopontine angle, including the brain stem and the lower cranial nerves. It enabled identification of both the origin of the facial nerve at the brain stem and the lateral segment of the nerve in the internal auditory canal. Anterior extensions of tumor growing through the tentorial hiatus were easily removed. The results in these 15 patients show that this approach is excellent for total removal of large acoustic neuromas with preservation of the facial nerve. It is especially suitable for large tumors with anterior extensions.