bluuebunny/crossref_metadata_2025_split huggingface dataset:
Brain kininogen following experimental brain injury: evidence for a secondary event
Authors: Ellis Earl F. , Chao Julie , Heizer Marcia L. 
Published: May 2009

✓ Previous studies have shown that following experimental brain injury cerebral arterioles dilate and display endothelial lesions and reduced responsiveness to hypocapnia. These abnormalities are caused by cyclooxygenase-dependent free radical generation. There is evidence that the kallikrein-kinin system may in part stimulate the cyclooxygenase-dependent damage since bradykinin is a powerful stimulator of prostaglandin formation and it has recently been shown that a specific kinin receptor blocker decreases the arteriolar abnormalities caused by injury. In order to further examine the hypothesis that the kallikrein-kinin system is important in inducing damage, rat brain tissue was examined for kininogen, the precursor of kinins, at 10 minutes and 1, 3, 6, 15, 24, 48, and 72 hours after injury. A fluid-percussion brain injury device was attached over the right cerebral cortex of rats and a 1.6-atmosphere pressure injury was administered. The kininogen content was determined by a radioimmunoassay procedure in tissues which were free of intravascular blood.
After injury, bleeding was confined mainly to the right hemisphere. The kininogen content in the right hemisphere was significantly elevated by one hour after injury, continued to rise until 15 hours after injury, then was significantly decreased by 2 days after injury. In the left hemisphere, kininogen was significantly elevated at 1 hour postinjury, returned toward control levels over the 3- to 6-hour period after injury, then was again elevated at 15 hours after injury. These studies also show that brain water and cerebrovascular permeability were greater at 15 hours postinjury than at earlier time points. The data further support a role for the kallikrein-kinin system in brain injury and, when considered with the results of other studies, suggest that a secondary event is occurring in the 12- to 24-hour period after neural injury. The authors hypothesize that this secondary event is related to endothelial and vascular repair and may be important for the return of normal cerebrovascular function.
Intracranial pressure monitoring in the posterior fossa: a preliminary report
Authors: Rosenwasser Robert H. , Kleiner Laurence I. , Krzeminski Joseph P. , Buchheit William A. 
Published: May 2009

✓ Direct therapeutic drainage and intracranial pressure monitoring from the posterior fossa has never been accepted in neurosurgical practice. Potential complications including cerebrospinal fluid leak, cranial nerve palsies, and brain-stem irritation have been a major deterrent. The authors placed a catheter for pressure monitoring in the posterior fossa of 20 patients in the course of posterior fossa surgery: 14 patients with acoustic schwannomas, four with posterior fossa meningiomas, one with cerebellar hemangioblastoma, and one with a solitary cerebellar metastatic lesion. A Richmond bolt was also placed in the frontal area.
Continuous monitoring of the supratentorial and infratentorial compartments was performed for 48 hours. During the first 12 hours the posterior fossa pressure was 50% greater than that of the supratentorial space in all patients (p < 0.01). Over the next 12 hours the supratentorial pressure was 10% to 15% higher than the posterior fossa pressures in all patients, and by 48 hours of monitoring the pressures had equilibrated. There was no mortality or morbidity referable to insertion of the posterior fossa catheter.
The conclusions drawn from this study are that: 1) direct monitoring and drainage of the posterior fossa is safe and effective; and 2) within the early postoperative period, the supratentorial pressures failed to reflect what is taking place within the posterior fossa. The implications and advantages of direct posterior fossa monitoring in the postoperative patient are discussed.
Detachable balloon embolization therapy of posterior circulation intracranial aneurysms
Authors: Higashida Randall T. , Halbach Van V. , Cahan Leslie D. , Hieshima Grant B. , Konishi Yoshifumi 
Published: May 2009

✓ Treatment of complex and surgically difficult intracranial aneurysms of the posterior circulation is now being performed with intravascular detachable balloon embolization techniques. The procedure is carried out under local anesthesia from a transfemoral arterial approach, which allows continuous neurological monitoring. Under fluoroscopic guidance, the balloon is propelled by blood flow through the intracranial circulation and, in most cases, can be guided directly into the aneurysm, thus preserving the parent vessel. If an aneurysm neck is not present, test occlusion of the parent vessel is performed and, if tolerated, the balloon is detached.
Twenty-six aneurysms in 25 patients have been treated by this technique. The aneurysms have involved the distal vertebral artery (five cases), the mid-basilar artery (six cases), the distal basilar artery (11 cases), and the posterior cerebral artery (four cases). The aneurysms varied in size and included three small (< 12 mm), 15 large (12 to 25 mm), and eight giant (> 25 mm). Fifteen patients (60%) presented with hemorrhage and 10 patients (40%) with mass effect. In 17 cases (65%) direct balloon embolization of the aneurysm was achieved with preservation of the parent artery. In nine cases (35%), because of aneurysm location and size, occlusion of the parent vessel was performed. Complications from therapy included three cases of transient cerebral ischemia which resolved, three cases of stroke, and five deaths due to immediate or delayed aneurysm rupture. The follow-up period has ranged from 2 months to 43 months (mean 22.5 months).
In cases where posterior circulation aneurysms have been difficult to treat by conventional neurosurgical techniques, intravascular detachable balloon embolization may offer an alternative therapeutic option.
Control of extraneural metastasis of a primary intracranial nongerminomatous germ-cell tumor
Authors: Watterson Jan , Priest John R. 
Published: May 2009

✓ Primary intracranial germ-cell tumors are infrequently occurring neoplasms which most often arise in the pineal or sellar regions. Germinomas are seen more frequently than nongerminomatous germ-cell tumors; they are often curable with radiotherapeutic approaches, or with chemotherapy in the rare instance of extraneural metastasis. Nongerminomatous germ-cell tumors are relatively radioresistant and when extraneural metastasis has occurred, they have been fatal in all of the 32 previously reported cases.
The case of a 14-year-old girl with a mixed malignant germ-cell tumor arising in the pineal region is reported. Extraneural metastasis to the lung developed 12 months after whole-brain radiotherapy was completed. She was treated with etoposide (VP-16), high-dose cisplatin, vinblastine, and bleomycin and is currently without evidence of disease 46 months postmetastasis.
Vacuum-stiffened beanbag for cranial remodeling procedures in modified prone position
Authors: Park T. S. , Broaddus William C. , Harris Mark , Persing John A. , Jane John A. 
Published: May 2009

✓ In surgical correction of multiple-suture synostosis, placing the patient in the modified prone position permits access to the calvarium from the supraorbital ridge to the occipital bone below the transverse sinus. The modified prone position thereby enables surgeons to perform cranial remodeling procedures at one stage under direct vision, contributing to improved surgical results. However, no satisfactory head-frame for this position has been available.
The authors report the successful use of a vinyl bag filled with styrofoam beads to achieve the modified prone position in young children. This widely available, economical device provides a safe, reliable means of positioning the child's head for cranial remodeling procedures.
A century of change in neurosurgery at Johns Hopkins: 1889–1989
Authors: Long Donlin M. 
Published: May 2009

✓ Neurosurgical admissions to The Johns Hopkins Hospital during the first year of its existence, the first and last years of Harvey Cushing's practice, the last years of Walter Dandy's practice, the last years of Earl Walker's tenure, and the current neurosurgical case load are reviewed. Sixteen patients with neurosurgical problems were admitted during the first year of the hospital's existence. In the first year of Harvey Cushing's staff appointment, 38 neurosurgical patients were admitted. Infection, trauma, and trigeminal neuralgia were the most common neurosurgical problems at that time. When Harvey Cushing retired in 1912, his practice had grown to 100 operations per year. By the end of Walter Dandy's tenure, the surgical volume was much larger, more than 500 major operations per year.
The development of neurosurgery virtually can be mirrored in the practice of neurosurgery under Harvey Cushing and Walter Dandy. From its humble beginnings in the treatment of trauma and infection, neurosurgery has expanded to cover all forms of intracranial disease, virtually every aspect of spinal disease, vascular disease (both intracranial and extracranial), and peripheral nerve injury. The centennial celebration at Johns Hopkins may be considered a centennial for neurosurgery. As we reflect upon our foundations, it is worthwhile to ask what changes we will contribute to the further development of neurosurgery in the next century.
Surgery of spinal nerve schwannoma
Authors: Kim Phyo , Ebersold Michael J. , Onofrio Burton M. , Quast Lynn M. 
Published: May 2009

✓ When surgically removing a spinal nerve schwannoma, preservation of the involved root is attempted and may be feasible. However, in large tumors, sacrifice of the nerve root is often required to achieve total removal of the tumor, and the resection does not always result in postoperative neurological deficit. The present study was designed to determine the incidence and extent of neurological deficit as correlated with resection of the root, performed between 1976 and 1987 in 86 cases at the time of total removal of spinal schwannoma. Thirty-one patients underwent sacrifice of a root critical for the function of the upper (C5–T1, 14 cases) or the lower extremities (L3–S1, 17 cases). This report is limited to these 31 cases. Only seven patients (23%) developed detachable motor or sensory deficits postoperatively. All deficits were no more than partial loss of strength or sensation. Fifteen of the 31 patients had large tumors with extradural components, which necessitated sacrifice of the entire motor and sensory radix; however, 11 (76%) of these 15 did not develop any deficits referrable to the involved myotome or dermatome. Six cases showed histological characteristics of “neurofibroma,” with axons intermingled in the tumor, and none developed a postoperative deficit. Preoperative electromyography was performed in 23 cases. Of 13 patients with findings of denervation, five developed deficits after surgery; the other 10 patients showed no evidence of denervation, and none had deficits after surgery.
These results indicate that the spinal roots giving origin to schwannoma are frequently nonfunctional at the time of surgery, and risks of causing disabling neurological deficit after sacrificing these roots are small.
Surgical alternatives in the treatment of cavernous sinus aneurysms
Authors: Diaz Fernando G. , Ohaegbulam Sam , Dujovny Manuel , Ausman James I. 
Published: May 2009

✓ Direct surgery on aneurysms in the cavernous sinus is a formidable technical procedure. The intimate relationship of the intracavernous carotid artery to the venous structures and to the cranial nerves make surgical access difficult at best. Thirty-two of 356 aneurysm patients presented with symptomatic aneurysms originating from the intracavernous internal carotid artery. Twenty-one patients had aneurysms contained entirely within the cavernous sinus, and in 11 others the aneurysms arose within the cavernous sinus and extended into the subarachnoid space. Of the purely intracavernous aneurysms there were five small aneurysms (< 25 mm) and 16 giant (≥ 25 mm) aneurysms. Fifteen patients with purely intracavernous lesions had a superior orbital fissure syndrome, and six had a variety of other symptoms. Of 11 patients with subarachnoid extension, five had a subarachnoid hemorrhage (Grade I or II), five had ipsilateral visual loss, and one had periorbital pain. The aneurysms were treated as follows: Group 1 received progressive ligation of the internal carotid artery in the neck with a Selverstone clamp and a surface superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis (purely intracavernous in nine, and with subarachnoid extension in one); Group 2 underwent trapping of the internal carotid artery and a deep STA-MCA anastomosis (purely intracavernous in seven); and Group 3 had direct clipping of the aneurysm (purely intracavernous in five, and with subarachnoid extension in 10).
The cavernous sinus was entered directly through its roof by a pterional craniotomy with radical removal of the optic canal, lesser sphenoid wing, and lateral and superior orbital walls. Proximal control of the internal carotid artery was obtained through a cervical incision. Two patients in Group 1 developed transient neurological deficits, which resolved. Two patients in Group 2 developed a cerebral infarction, one of whom died; in both of these patients, the anastomosis was completed after the internal carotid artery occlusion. Two patients in Group 3 progressed from marked visual loss to blindness of the same side, and one developed an intraventricular hemorrhage during induction of anesthesia and died without surgery. It is proposed that a direct approach to symptomatic aneurysms in the cavernous sinus is the best initial alternative. When this approach is not feasible, a trapping procedure preceded by a high-flow extracranial-intracranial anastomosis may be considered. Although the authors have been able to clip aneurysms of various sizes, this has not been possible in all patients. Further work is needed in this area.
Clinical analysis and prognostic study of ossified ligamentum flavum of the thoracic spine
Authors: Shiokawa Kazuhiko , Hanakita Junya , Suwa Hideyuki , Saiki Masaaki , Oda Masashi , Kajiwara Motohiro 
Published: May 2009

Object. A variety of factors may affect surgery-related outcome in patients with ossification of the ligamentum flavum (OLF) of the thoracic spine. The aim of this study was to determine these factors on the basis of preoperative clinical and radiological findings.
Methods. The authors treated 31 cases of symptomatic thoracic OLF between 1988 and 1999. The following factors were retrospectively studied: patient age, sex, morbidity level, initial symptoms, chief complaint, duration of symptoms, patellar reflex, Achilles reflex, computerized tomography (CT) finding, presence of intramedullary change determined by magnetic resonance imaging, coexistent spinal lesions, preoperative grade, and postoperative grade.
A decompressive laminectomy was performed in all cases. In 29 patients (94%) improved symptoms were demonstrated postoperatively. In terms of functional prognosis, the preoperative duration of symptoms was significantly shorter in the group of patients with excellent outcomes than in those with fair outcomes (p < 0.05).
No significant difference was observed in the correlation between other factors. To evaluate the degree of preoperative thoracic stenosis and the severity/extent of OLF-induced spinal compression, we used an original OLF CT scoring system. A score of excellent on the CT scale tended to indicate an excellent prognosis (p < 0.01).
Conclusions. Thoracic OLF frequently develops in the lower-thoracic spine in middle-aged men, and it is complicated by various spinal lesions in many cases. Early diagnosis and treatment are important for understanding the clinical symptoms and imaging diagnosis because the present findings suggest that a delay in diagnosis and treatment correlates with the functional prognosis postoperatively.
Autotransfusion by cell saver technique in surgery of lumbar and thoracic spinal fusion with instrumentation
Authors: Chanda Amitabha , Smith Donald R. , Nanda Anil 
Published: May 2009

Object. The authors used a modern cell saver technique to perform autotransfusion in patients undergoing instrument-assisted lumbar and/or thoracic spinal fusion, in whom significant blood loss was anticipated. The safety and benefits of this procedure as well as its cost effectiveness were analyzed.
Methods. The authors studied 50 patients who underwent lumbar and/or thoracic spinal fusion in which instrumentation was placed between January 1998 and June 2000 and in whom an estimated blood loss of 500 ml or more was expected. All surgeries were conducted by a single neurosurgeon (D.R.S.). During surgery, the Brat 2 cell saver system was used to salvage the autologous blood. The anesthesiologist and surgeon jointly decided, on the basis of hematocrit and clinical stability, whether transfusion was necessary in each patient. Various parameters (hematocrit, plasma and urine hemoglobin, platelet counts, coagulation profile, and serum bilirubin) were measured pre-, intra-, and postoperatively.
Thirty-three patients (66%) required transfusion. The mean blood loss in these patients was 1046 ml. The most important factor affecting blood loss was the number of levels fused (p < 0.0001). Only two patients required postoperative homologous transfusion. The mean decrease in hematocrit was 7.82%. The maximum reduction of platelet count was limited to 80,000/mm3. Major complications such as hemoglobinuria, coagulopathy, cardiopulmonary problems, air embolism, and major sepsis were not observed in this study.
Conclusions. Autotransfusion performed using a modern cell saver technique is safe and has many advantages over homologous transfusion. It conserves the homologous blood resources. The costs of the two modes are statistically comparable when greater than 500 ml of red blood cell transfusion is necessary.
Improved accuracy of computer-assisted cervical pedicle screw insertion
Authors: Kotani Yoshihisa , Abumi Kuniyoshi , Ito Manabu , Minami Akio 
Published: May 2009

Object. The authors introduce a unique computer-assisted cervical pedicle screw (CPS) insertion technique used in conjunction with specially modified original pedicle screw insertion instruments. The accuracy of screw placement as well as surgery-related outcome and complication rates were compared between two groups of patients: those in whom a computer-assisted and those in whom a conventional manual insertion technique was used.
Methods. The screw insertion guiding system consisted of a modified awl, probe, tap and a screwdriver specially designed for a computer-assisted CPS insertion. Using this system, real-time instrument/screw tip information was three dimensionally identified in each step of screw insertion. Seventeen patients underwent CPS fixation in which a computer-assisted surgical navigation system was used. The cervical disorders consisted of spondylotic myelopathy with segmental instability or kyphosis, metastatic spinal tumor, rheumatoid spine, and postlaminectomy kyphosis. The rate of pedicle wall perforation was significantly lower in the computer-assisted group than that in the other group (1.2 and 6.7%, respectively; p < 0.05). The screw trajectory in the horizontal plane was significantly closer to the anatomical pedicle axis in the computer-assisted group compared with the manual insertion group (p < 0.05). This factor significantly reduced the incidence of screw perforation laterally. Complications such as neural damage or vascular injury were not demonstrated in the computer-assisted group (compared with 2% in the manual insertion treatment group). The overall surgery-related outcome was satisfactory.
Conclusions. In contrast to the previously reported computer-assisted technique, our CPS insertion technique provides real-time three-dimensional instrument/screw tip information. This serves as a powerful tool for safe and accurate pedicle screw placement in the cervical spine.
Case study of a one‐sided attack by multiple troop members on a nontroop adolescent male and the death of Japanese macaques (Macaca fuscata)
Authors: Shimada Masaki , Uno Takeharu , Nakagawa Naofumi , Fujita Shiho , Izawa Kosei 
Published: May 2009

AbstractAn adolescent wild male Japanese macaque (Macaca fuscata), following Kinkazan A troop, was attacked one‐sidedly by multiple members of the troop. The victim was identified as PI, and was estimated to be seven±one year old. The aggressive interaction was recorded by video camera until the end. Although at least 16 troop members approached PI more than once, only three males (one adult, two adolescents) of A troop attacked him. PI kept crouching throughout the attack, then escaped to the shore and dived into the sea. The interaction continued for more than one hour. PI was found dead a few hours after the end of interaction. The damage caused by the assailants was not the direct cause of PI's death; it was due to hypothermia caused by drifting in the sea. PI's life history was reconstructed from past records. PI was a normal adolescent male who migrated from an all‐male group around B1 troop and started ranging around A troop. The aggressive interaction is believed to be a typical example of conflict between troop males and a nontroop male. The interaction period was very long compared with previous reports on such conflicts among Japanese macaques. PI kept crouching in open areas, exposing himself as a potential competitor for the resources of the troop, and did not show any submissive or reconciliatory behavior toward the troop males. This may be why the troop males did not stop the attack. Aggr. Behav. 35:334–341, 2009. © 2009 Wiley‐Liss, Inc.
Kinetic modeling of catalytic conversion of methylcyclohexane over USY zeolites: Adsorption and reaction phenomena
Authors: Al‐Sabawi Mustafa , de Lasa Hugo 
Published: May 2009

AbstractCatalytic conversion of cycloparaffins is a complex process involving competing reaction steps. To understand this process, FCC experiments using methylcyclohexane (MCH) on USY zeolite catalysts were carried out in the mini‐fluidized CREC riser simulator. Runs were developed under relevant FCC process conditions in terms of partial pressures of MCH, temperatures (450–550°C), contact times (3–7 s), catalyst‐oil mass ratios (5), and using fluidized catalysts. MCH overall conversions ranged between 4 to 16 wt %, with slightly higher conversions obtained using the larger zeolite crystallites. Moreover, it was found that MCH undergoes ring opening, protolytic cracking, isomerization, hydrogen transfer and transalkylation. A heterogeneous kinetic model for MCH conversion including thermal effects, adsorption and intrinsic catalytic reaction phenomena was established. Adsorption and kinetic parameters were determined, including the heat of adsorption (−40 kJ/mol), as well as thermal and primary catalytic intrinsic activation energies, which were in the range of 43–69 kJ/mol, and 50–74 kJ/mol, respectively. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Erste Röntgenstrukturanalysen von Rhodium(III)‐η1‐Allyl‐Komplexen und ein plausibler Mechanismus für allylische Isomerisierungsreaktionen
Authors: Wucher Barbara , Moser Michael , Schumacher Stephanie A. , Rominger Frank , Kunz Doris 
Published: May 2009

AbstractAllyltransfer von Metall zu Metall: Anhand der ersten strukturell charakterisierten Rh(η1‐allyl)‐Komplexe wird gezeigt, dass der σ‐gebundene Allylsubstituent von einem RhIII‐ auf einen RhI‐Komplex im schnellen Gleichgewicht übertragen werden kann. Dies könnte die Abnahme der Regioselektivität in Rh‐katalysierten allylischen Alkylierungen erklären, für die Komplex 1 ein aktiver Katalysator ist.magnified image