bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chronic intrathecal baclofen administration for control of severe spasticity
Authors: Lazorthes Yves , Sallerin-Caute Brigitte , Verdie Jean-Claude , Bastide Raymond , Carillo Jean-Pierre 
Published: May 2009

✓ Baclofen, the most effective drug for treating spasticity, is a specific agonist of gamma-aminobutyric acid-B receptors, and is very abundant in the superficial layers of the spinal cord. Given orally, baclofen does not easily penetrate the blood-brain barrier, and is distributed equally to the brain and spinal cord. Direct intrathecal administration was given in order to change the distribution of the drug by preferentially perfusing the spinal cord. Eighteen patients presenting a severe spastic syndrome were treated with chronic intrathecal infusion of baclofen in the lumbar cerebrospinal fluid. After clinical preselection, 38 patients were implanted with a lumbar access port allowing long-term trials in order to determine the efficacy of baclofen therapy and the effective 12-hour dose. The 18 patients selected for chronic administration were implanted with a programmable pump. The pathology in these cases was: multiple sclerosis (6 cases), posttrauma spastic syndrome (eight cases), and (one case each) cerebral palsy, ischemic cerebral lesion, spinal ischemia, and transverse myelitis. The mean follow-up period was 18 months (range 4 to 43 months).
The clinical results were evaluated according to muscular hypertony on Ashworth's scale (changed for occurrence of painful spasms) and functional improvement. Results were better for spastic syndrome secondary to traumatic medullary lesion than for demyelinating disease. Hypertonia was improved in all cases as confirmed by the registration of the Hoffman (H) reflex. Painful muscular spasms disappeared in 14 of the 16 affected patients. Significant functional improvement was noted in nine patients and was considerable in three. The risk of side effects secondary to overdose (such as excessive hypotonia or central depression) and the absence of a specific baclofen antagonist stresses the necessity for accurate determination of the efficient dose. After an initial titration period and adjustment of the therapeutic dose, the individual doses were from 21 to 500 µg/24 hrs (mean 160 µg/24 hrs). This new conservative method is very effective, perfectly reversible, and safe when administered in conditions favorable to its use.
Alterations in Na+-K+-ATPase activity and β-endorphin content in acute ischemic brain with and without naloxone treatment
Authors: Furui Tomoo , Tanaka Issei , Iwata Kinjiro 
Published: May 2009

✓ The Na+-K+-adenosine triphosphatase (Na+-K+-ATPase) activity and β-endorphin immunoreactivity were determined in rat brain at the acute stage of ischemia produced by unilateral occlusion of the middle cerebral artery (MCA). The effect of pretreatment with naloxone on these activities was also evaluated in the same model. After MCA occlusion, Na+-K+-ATPase activity was promptly reduced in the ischemic hemisphere and remained at a lower level than in the contralateral hemisphere during 90 minutes of ischemia. A single intraperitoneal 0.5-mg injection of naloxone prior to MCA occlusion attenuated the inactivation. On the other hand, β-endorphin immunoreactivity was significantly increased following ischemia. The increase was marked in the ischemic hemisphere and was also observed in the contralateral hemisphere; this increase was not affected by the administration of naloxone.
These results indicate the possibility that naloxone contributes to protecting the brain from ischemia through stabilizing the cellular membrane. The possible mechanism by which naloxone attenuates the inactivation of Na+-K+-ATPase in the ischemic brain is discussed in view of alterations of the central β-endorphin system during ischemia.
Multicellular tumor spheroids from human gliomas maintained in organ culture
Authors: Bjerkvig Rolf , Tønnesen Audun , Laerum Ole Didrik , Backlund Erik-Olof 
Published: May 2009

✓ Tumor tissue from seven human gliomas was maintained in long-term agar overlay culture as multicellular organotypic spheroids. Light microscopic and ultrastructural observation of the spheroids displayed morphological features similar to those of the original tumor tissue in vivo; in this respect they were different from spheroids obtained from permanent cell lines. The spheroids contained preserved vessels, connective tissue, and macrophages, revealing a close resemblance to the conditions in the original tumor.
Flow cytometric deoxyribonucleic acid measurements of cells from the tumor spheroids and from biopsy material obtained directly from the operation revealed the same ploidy and the same amount of proliferating cells in the spheroids as in the original tumor. Fluorescence microscopy using bromodeoxyuridine (BUdR) incorporation and anti-BUdR monoclonal antibody confirmed the proliferative potential of tumor cells in the spheroids. Diameter measurements showed that the size of the spheroids from two of the tumors increased over time while in three other cases it decreased. Spheroids from the remaining two tumors showed no change in size, even after 80 days in culture. These growth data and the relatively high number of proliferating cells, as measured by flow cytometry, indicate that the degree of cell proliferation and cell loss from the spheroids are closely linked, as is the case for tumors in vivo. The culture system presented provides a valuable alternative to propagation of human tumors in animals.
Intramedullary ependymoma of the spinal cord
Authors: McCormick Paul C. , Torres Roland , Post Kalmon D. , Stein Bennett M. 
Published: May 2009

✓ A consecutive series of 23 patients underwent operative removal of an intramedullary spinal cord ependymoma between January, 1976, and September, 1988. Thirteen women and 10 men between the age of 19 and 70 years experienced symptoms for a mean of 34 months preceding initial diagnosis. Eight patients had undergone treatment prior to tumor recurrence and referral. Mild neurological deficits were present in 22 patients on initial examination. The location of the tumors was predominantly cervical or cervicothoracic. Radiological evaluation revealed a wide spinal cord in all cases. Magnetic resonance (MR) imaging was the single most important radiological procedure. At operation, a complete removal was achieved in all patients. No patient received postoperative radiation therapy. Histological examination revealed a benign ependymoma in all cases.
The follow-up period ranged from 6 to 159 months (mean 62 months) with seven patients followed for a minimum of 10 years after surgery. Fourteen patients underwent postoperative MR imaging at intervals ranging from 8 months to 10 years postoperatively. No patient has been lost to follow-up review and there were no deaths. No patient showed definite clinical or radiological evidence of tumor recurrence during the follow-up period. Recent neurological evaluation revealed functional improvement from initial preoperative clinical status in eight patients, no significant change in 12 patients, and deterioration in three patients. The data support the belief that long-term disease-free control of intramedullary spinal ependymomas with acceptable morbidity may be achieved utilizing microsurgical removal alone.
Percutaneous microcompression of the gasserian ganglion for trigeminal neuralgia
Authors: Lobato Ramiro D. , Rivas Juan J. , Sarabia Rosario , Lamas Eduardo 
Published: May 2009

✓ The authors report 144 cases of trigeminal neuralgia treated by percutaneous microcompression of the trigeminal ganglion (PMTG). The operation was performed under short-lasting barbiturate anesthesia without endotracheal intubation. Meckel's cave was cannulated with a No. 4 Fogarty catheter and the balloon was inflated for 1 minute. The average intraluminal pressure required for adequate compression of the ganglion was about 1200 mm Hg. All patients were initially relieved of their neuralgia. In a follow-up period ranging from 6 months to 4½ years, 14 patients (9.7%) developed recurrence of pain between 10 and 35 months after surgery. Eleven patients underwent a second PMTG. All nine early failures and 10 of the 11 late recurrences occurred in cases with technical deficiencies. Most of the minor surgical complications observed were also related to avoidable technical errors. There were no anesthetic complications and no deaths.
All patients developed mild to moderate postoperative hemifacial numbness with or without objective hypesthesia. Both subjective and objective deficits gradually diminished with time and were well tolerated. One year after the operation nearly 40% of the patients still had patches of slightly decreased sensation in one or more trigeminal divisions and 16% had mild dysesthesia. Anesthesia dolorosa or keratitis was not reported. The PMTG procedure is easy to perform and requires a short operative time and a brief period of hospitalization. It is well tolerated by patients, who describe it as a totally pain-free experience. Morbidity is minimal and recurrence of neuralgia does not seem to be higher than with alternative procedures.
Management morbidity and mortality of poor-grade aneurysm patients
Authors: Bailes Julian E. , Spetzler Robert F. , Hadley Mark N. , Baldwin Hillel Z. 
Published: May 2009

✓ Preliminary experience with the occasional good survival of patients in Hunt and Hess Grade IV or V with aneurysmal subarachnoid hemorrhage (SAH) led to a prospective management protocol employed during a 2½-year period. The protocol utilized computerized tomography (CT) scanning to diagnose SAH and to obtain evidence for irreversible brain destruction, consisting of massive cerebral infarction with midline shift or dominant basal ganglia or brain-stem hematoma. These patients, along with those who exhibited poor or absent intracranial filling on CT or angiography, were excluded from active treatment and given supportive care only. All other patients had immediate ventriculostomy placement and, if intracranial pressure (ICP) was controllable (≤ 30 cm H2O without an intracranial clot or ≤ 50 cm H2O in the presence of a clot), went on to have craniotomy for aneurysm clipping. Aggressive postoperative hypertensive, hypervolemic, hemodilutional therapy was subsequently employed. Of 54 patients with poor-grade aneurysms, ventriculostomy was placed in 47 (87.0%) and yielded high ICP's in the overwhelming majority, with the mean ICP being 40.2 cm H2O. Nineteen poor-grade aneurysm patients received no surgical treatment and survived a mean of 31.8 hours with 100% mortality. Thirty-five patients underwent placement of a ventriculostomy, craniotomy for aneurysm clipping and intracranial clot evacuation, and postoperative hypertensive, hypervolemic, hemodilutional therapy. The outcome at 3 months of the 35 patients who were selected for active treatment was good in 19 (54.3%), fair in four (11.4%), poor in four (11.4%), and death in eight (22.9%).
It is concluded that poor-grade aneurysm patients usually present with intracranial hypertension, even those without an intracranial clot. Based on radiographic rather than neurological criteria, a portion of these patients can be selected for active and successful treatment. Increased ICP can be present without ventriculomegaly, and immediate ventriculostomy should be performed. As long as ICP is controllable, craniotomy and postoperative intensive care can effect a favorable outcome in a significant percentage of these patients.
Somatosensory evoked potentials and neurological grades as predictors of outcome in acute spinal cord injury
Authors: Li Chen , Houlden David A. , Rowed David W. 
Published: May 2009

✓ An analysis of Motor Index score, pinprick sensory score, joint position sense score, somatosensory evoked potential (SSEP) grade in the ulnar (SSEPu) and posterior tibial (SSEPt) regions, and overall SSEP grade (mean SSEPu+t) was conducted in 36 patients with cervical spinal cord injuries to determine the relationship of these scores, both individually and in combination, to functional outcome (as determined using the Barthel Index) at 6 months after injury. The clinical and electrophysiological data were obtained on the same day within 2 weeks after injury. Nineteen patients underwent two SSEP tests 1 week apart within the first 3 weeks following injury in an attempt to identify mean SSEPu+t improvement. Somatosensory evoked potential grading was based on the presence or absence of the cortical evoked potential, the amplitude of the early cortically generated waveform (P22 or P37), and the interpeak latency across the lesion site.
Mean SSEPu+t had the strongest individual relationship with outcome (R-square 0.75, p < 0.0001) and mean SSEPu+t improvement over a 1-week interval during the first 3 weeks after injury was associated with Motor Index score improvement over a 6 month period. Joint position sense score was the best clinical predictor of outcome (R-square 0.64, p < 0.0001). Mean SSEPu+t correlated with outcome more closely than the combination of Motor Index score and pinprick sensory score. Mean SSEPu+t in combination with all three clinical indicators produced the strongest correlation with outcome (R-square 0.87, p < 0.0001).
This study confirms the prognostic value of quantitative SSEP analysis for patients with acute spinal cord injuries.
Influence of PGE2- and cAMP-modulating agents on human glioblastoma cell killing by interleukin-2-activated lymphocytes
Authors: Kuppner Maria C. , Sawamura Yutaka , Hamou Marie-France , de Tribolet Nicolas 
Published: May 2009

✓ Human glioblastoma cells secrete factors, such as prostaglandin E (PGE) and transforming growth factor beta type 2, which are capable of suppressing several immune functions. The present study investigated the effect of PGE2 and agents known to increase intracellular cyclic adenosine monophosphate (cAMP) levels on 1) the induction of lymphokine-activated killer (LAK) cell activity from the peripheral blood lymphocytes (PBL) of both normal and glioma patients and on 2) the cytolytic activities of tumor-infiltrating lymphocytes (TIL's) isolated from malignant gliomas after expansion in vitro with interleukin-2 (IL-2). Cytolytic activity was measured against autologous and allogeneic tumor cells and the natural killer-resistant Daudi cell line. The results demonstrate that PGE2 and agents known to increase intracellular cAMP levels can significantly suppress the IL-2-dependent generation of cytolytic activity from the PBL of normal and glioma patients and from glioblastoma-derived TIL's. The inhibitory effects of these agents could not be reduced by higher concentrations of IL-2 or by cyclic guanosine monophosphate.
Although the suppressive effect of PGE2 was most significant during the early stages of LAK cell generation, an inhibitory effect was still evident when PGE2 was added directly to the cytotoxicity assay. Secretion of PGE2 by glioblastoma cells in vivo may regulate both the generation of an immune response and the effectiveness of adoptively transferred immune cells.
Clinical experience with radiofrequency and laser DREZ lesions
Authors: Young Ronald F. 
Published: May 2009

✓ Dorsal root entry zone (DREZ) lesions were used to treat intractable pain due to deafferentation in 78 patients managed between 1981 and 1988. Etiology of pain included avulsion of brachial or lumbosacral plexuses (27 cases), spinal cord injury (20 cases), amputation (nine cases), post-herpetic neuralgia (16 cases), and cauda equina injury (six cases). Three different lesioning techniques were employed: a radiofrequency (rf) method using a 0.5 × 2-mm stainless steel electrode with control of electric current and duration (Group 1: 21 cases); the CO2 laser (Group 2: 20 cases); and an rf method, using a 0.25 × 2-mm stainless steel electrode with control of electrode temperature and duration (Group 3: 37 cases).
Overall, 48 (61.5%) of 78 patients received satisfactory pain relief, defined as a 50% or greater reduction in pain intensity, cessation of narcotic analgesic usage, and improvement in functional capacity. Fourteen (67%) of the 21 Group 1 patients obtained effective pain relief, compared to nine (45%) of the 20 Group 2 patients and 25 (68%) of the 37 Group 3 patients. Neurological complications including mainly ipsilateral leg weakness or loss of proprioception occurred in 52.3% of the patients in Group 1, 15% of the Group 2 patients, and 8.1% of the Group 3 patients. These results support the view that DREZ lesions may be made most effectively and safely with the rf lesioning technique associated with control of electrode temperature and duration.
Cerebral radioprotection by pentobarbital: dose-response characteristics and association with GABA agonist activity
Authors: Olson Jeffrey J. , Friedman Robert , Orr Kathryn , Delaney Thomas , Oldfield Edward H. 
Published: May 2009

✓ Pentobarbital reduces cerebral radiation toxicity; however, the mechanism of this phenomenon remains unknown. As an anesthetic and depressant of cerebral metabolism, pentobarbital induces its effects on the central nervous system by stimulating the binding of gamma-aminobutyric acid (GABA) to its receptor and by inhibiting postsynaptic excitatory amino acid activity. The purpose of this study is to investigate the role of these actions as well as other aspects of the radioprotective activity of pentobarbital.
Fischer 344 rats were separated into multiple groups and underwent two dose-response evaluations. In one set of experiments to examine the relationship of radioprotection to pentobarbital dose, a range of pentobarbital doses (0 to 75 mg/kg) were given intraperitoneally prior to a constant-level radiation dose (70 Gy). In a second series of experiments to determine the dose-response relationship of radiation protection to radiation dose, a range of radiation doses (10 to 90 Gy) were given with a single pentobarbital dose (60 mg/kg intraperitoneally). Further groups of animals were used to evaluate the importance of the timing of pentobarbital administration, the function of the (+) and (−) isomers of pentobarbital, and the role of an alternative GABA agonist (diazepam). In addition, the potential protective effects of alternative methods of anesthesia (ketamine) and induction of cerebral hypometabolism (hypothermia) were examined.
Enhancement of survival time from acute radiation injury due to high-dose single-fraction whole-brain irradiation was maximal with 60 mg/kg of pentobarbital, and occurred over the range of all doses examined between 30 to 90 Gy. Protection was seen only in animals that received the pentobarbital before irradiation. Administration of other compounds that enhance GABA binding (Saffan and diazepam) also significantly enhanced survival time. Ketamine and hypothermia were without protective effect.
Protection from acute radiation-induced mortality by pentobarbital in the rat model is a reproducible phenomenon and is associated with the GABA agonistic activity of the compound. This property of GABA agonists offers the potential for a novel approach to enhancement of the efficacy of radiation therapy in the treatment of brain tumors.
Percutaneous retrogasserian glycerol rhizotomy
Authors: North Richard B. , Kidd David H. , Piantadosi Steven , Carson Benjamin S. 
Published: May 2009

✓ Eighty-five medically intractable trigeminal neuralgia patients treated by percutaneous retrogasserian glycerol rhizotomy (PRGR) were followed for 6 to 54 months. The median time to recurrence of symptoms refractory to medical therapy and requiring further intervention was 3 years (by Kaplan-Meier survival analysis). The median time to recurrence of symptoms requiring some form of medical treatment was 2 years. Following repeat PRGR for recurrent symptoms, the median time to recurrence was 1 year. Univariate log rank statistics and multivariate Cox proportional hazards modeling revealed significant associations between favorable outcome and female sex, absence of atypical features or associated cluster headache symptoms, success of prior carbamazepine therapy, duration of symptoms, and cerebrospinal fluid return during the procedure. A scoring system using prognostic factors has been developed based upon these findings.
Assessment of published studies of PRGR and of other treatments for trigeminal neuralgia is made difficult by the variety of outcome measures employed and variable follow-up intervals. The present study attempts to address these issues by definition of endpoints, statistical analysis of the data, and identification of important prognostic factors in a manner useful to the clinician.
Transcranial Doppler pulsatility in vasodilation and stenosis
Authors: Giller Cole A. , Hodges Kurt , Batjer H. Hunt 
Published: May 2009

✓ Although blood velocity in the major intracranial vessels is readily measured with transcranial Doppler ultrasound (TCD), the interpretation of velocity changes is by no means straightforward. For example, a velocity increase can arise from either a local stenosis or a decrease in downstream resistance, and these mechanisms have contradictory implications for blood flow. To determine whether TCD pulsatility might distinguish these two mechanisms, Doppler ultrasonic readings were taken from an artificial vascular model under conditions of either stenosis or distal dilation. In addition, TCD studies of nine patients with unihemispheric arteriovenous malformations (AVM's) and 16 TCD studies of seven patients with unihemispheric aneurysmal vasospasm were reviewed, and pulsatilities of the AVM's (representing decreased resistance) were compared with those of the vasospastic vessels (representing stenosis).
The average percentage drop in pulsatility in the vasodilated configuration of the model/percentage increase in velocity was 0.38 ± 0.08 (± standard error of the mean), while that for stenosis was 0.20 ± 0.01. Similar comparisons of the patient population yielded 0.67 ± 0.16 for the AVM group and 0.26 ± 0.04 for the vasospasm group. These differences were significant (p < 0.05). The fall in pulsatility associated with a given increase in velocity is significantly greater when the velocity increase arises from diminished downstream resistance than from stenosis.
Autonomic and histopathological effects of percutaneous trigeminal ganglion compression in the rabbit
Authors: Preul Mark C. , Long Phillip B. , Brown Jeffrey A. , Velasco Manuel E. , Weaver Michael T. 
Published: May 2009

✓ The histopathological and autonomic effects of percutaneous trigeminal ganglion compression for trigeminal neuralgia were studied in New Zealand White rabbits. Drops in mean arterial blood pressure of 38% and in heart rate of 30% were observed during compression (p < 0.0001). Corneal reflex, pinprick sensation, and mastication strength were intact in 13 of 14 rabbits after compression. These findings resembled the effects of percutaneous compression in humans and suggested that the New Zealand White rabbit is a useful model for the study of percutaneous compression.
Trigeminal sensory roots and ganglia from 14 rabbits killed at intervals from 1 to 84 days after percutaneous compression were sectioned and stained using immunoperoxidase for neurofilaments, hematoxylin and eosin, luxol fast blue, and cresyl echt violet. Focal axonal damage and demyelination were present 7 days after compression. No difference could be detected in the perikaryonal distribution of neurofilaments between compressed and control trigeminal ganglia. Focal demyelination and Schwann cell proliferation preceding remyelination were present in the trigeminal sensory root at 84 days. Differential injury of axons compared to trigeminal ganglion cell bodies suggests that axonal regeneration is possible and may contribute to the recovery of motor and sensory function in patients after percutaneous compression.