bluuebunny/crossref_metadata_2025_split huggingface dataset:
Parietal cephalocele: clinical importance of its atretic form and associated malformations
Authors: Yokota Akira , Kajiwara Hidehiko , Kohchi Masato , Fuwa Isao , Wada Hidetaka 
Published: May 2009

✓ In this study of atretic cephaloceles, the authors have considered the pedunculated or sessile type of cephalocele and also small nonpedunculated scalp defects developing in the vertex midline. Parietal cephaloceles were found in 15 infants (10 boys and five girls), and accounted for 37.5% of all cephaloceles. They consisted of four encephaloceles, six meningoceles, and five atretic cephaloceles. The clinical and morphological characteristics of parietal cephaloceles were investigated and compared with those arising at other locations. Parietal cephaloceles carried a much less favorable prognosis than those in the occipital region, regardless of the type of cephalocele; they were associated with cerebral malformations more frequently and were more severe than occipital cephaloceles. Grave congenital anomalies were found in 87% of patients with parietal cephalocele, and only two patients (neither of whom had any other malformation) attained normal development. Brain malformations were closely related to the site from which the cephalocele issued, and dorsal cyst malformation was found in eight patients with parietal cephalocele.Two types of atretic cephaloceles were found, each in a different location. The first type was an alopecic lesion occurring in the parietal midline; all five patients with this type had dorsal cyst malformations and none developed normally. The second type was a nodular lesion developing at the occipital midline, not associated with cerebral anomalies; all five patients with this type showed normal development. The pathogenesis of atretic cephaloceles and their associated intracranial malformations are discussed.
Reduction of cellular energy requirements
Authors: Zager Eric L. , Ames Adelbert 
Published: May 2009

✓ Protection of the brain and spinal cord against ischemia is a goal of vast clinical importance. One approach to this objective is to reduce the tissue's functional activity in order to preserve energy for the metabolic processes that are essential to viability. Experiments to explore ways of reducing function-related energy demands were performed on isolated rabbit retina, a well-characterized model of organized adult mammalian central nervous system (CNS) tissue. The retina was maintained in a nearly physiological state in a miniature “heart-lung” apparatus. Energy metabolism (oxygen consumption and glycolysis) and electrophysiological function (determined by electroretinogram) of thein vitroretina were monitored, and their responses to a series of agents that may reduce energy requirements were determined.Large reversible reductions in O2consumption, glycolysis, and electrophysiological function were seen in response to mild hypothermia ( −3° to −6°C), phenytoin (Dilantin, 100 to 200 mg/kg), chlordiazepoxide (Librium, 200µM), lithium (1 to 4 mM), Mg++(6 to 20 mM), strophanthidin (0.15 to 0.25µM), CO2(25% to 30%), 2-amino-5-phosphonovaleric acid (APV, 500µM), amiloride (1 mM), and dantrolene (1 mM). One retina was exposed simultaneously to a combination of six of these agents, which reduced its oxidative and glycolytic metabolism to less than 50% of the control level. The retina recovered metabolic and electrophysiological function after a 2½-hour exposure period. Other agents tested (diphenhydramine, midazolam, nifedipine, nimodipine, and quercetin) had effects on energy metabolism and electrophysiological function that were poorly reversible. Surprisingly little effect was seen in response to general anesthetic agents (thiopental and Althesin) and other CNS depressants (chlorpromazine, ethanol, lidocaine, paraldehyde, valproic acid, and baclofen). The presumed mechanisms through which these agents reduce cellular energy requirements, as well as their potential roles in the treatment of CNS ischemia, are discussed.
A comparative study of brain-stem auditory evoked potentials and blink reflexes in posterior fossa tumor patients
Authors: Zileli Mehmet , İdiman Fethi , Hiçdönmez Tufan , Övül İzzet , Tunçbay Erdem 
Published: May 2009

✓ Brain-stem auditory evoked potentials (BAEP's) and blink reflexes (BR's) were recorded from 40 patients with clinical and radiological evidence of posterior fossa tumors. They were examined in three groups according to the anatomical location of the lesion: Group A included 15 patients with midline tumors; Group B included 14 patients with cerebellar hemispheric tumors; and Group C included 11 patients with cerebellopontine angle (CPA) tumors. More of the 40 patients had BAEP abnormalities (32) than BR abnormalities (24). All of the 11 patients with CPA tumors had some kind of BAEP and BR abnormalities. The 14 patients with cerebellar tumors showed the next most frequent abnormalities: 12 related to the BAEP's and seven to the BR's. The 15 patients with midline tumors showed the least number of abnormalities: nine related to BAEP's and six to the BR's.
In the analysis of BAEP wave latencies and interpeak latencies, a wave III latency delay occurred in all groups; latencies of waves IV and V were more significantly delayed in patients with CPA and cerebellar hemispheric tumors, and the interpeak latencies of waves III–V and I–V were markedly prolonged only in patients with CPA tumors (p < 0.01).
In all tumor groups, early response (R1) of BR's was significantly delayed in comparison to a healthy volunteer control group (p < 0.01), but R1 was more pronounced in cases of CPA tumors when compared with the other tumor groups. Although significant delays in direct and consensual late reflex components (R2) of BR's were noted in comparison to the control group, this delay could not differentiate one tumor group from another.
It can be concluded that, while these tests reflect the functions of different cranial nerves and brain-stem tracts, BAEP monitoring is more sensitive than BR testing for the detection of brain-stem involvement in posterior fossa tumors. Cerebellopontine angle tumors almost always cause severe abnormalities in both tests. Cerebellar hemispheric tumors and midline tumors cause fewer changes in both BAEP's and BR's.
Effect of subarachnoid hemorrhage on intracranial pulse waves in cats
Authors: Cardoso Erico R. , Reddy Kesava , Bose Deepak 
Published: May 2009

✓ The influence of vasoconstrictors of intracranial arteries on the amplitude and configuration of the intracranial pulse wave (ICPW) was investigated. Continuous pressure recordings from the descending aorta (systemic arterial pressure) and the third cerebral ventricle (intracranial pressure) were obtained from anesthetized cats. Computerized analysis of the configuration, amplitude, and frequency spectrum of ventricular wave (ICPW) and aortic pulse wave (SAPW) was performed. Artificial cerebrospinal fluid (CSF), blood, or 5-hydroxytryptamine (5-HT) was injected intracisternally. In 24 control cats, 2 ml artificial CSF was injected into the cisterna magna. This produced a significant increase in amplitude of the ICPW but no change in the SAPW. Ten animals received 14 intracisternal injections of 2 ml autologous blood which caused narrowing of the amplitude of the ICPW as well as of all its components (P1, P2, and P3), with no significant change in the SAPW's. Eight animals were also subjected to cisternal injection of 2 ml of a 10−4-M solution of 5-HT, resulting in findings similar to those produced by autologous blood. Frequency spectrum of the intracranial and aortic pulse waves showed a high degree of correlation between wave amplitudes and height of the fundamental wave in the FFT record.
These results suggest that the cerebral vasospasm that follows cisternal injections of blood and 5-HT in cats can be diagnosed by analysis of the ICPW. This method may allow early diagnosis and continuous monitoring of cerebral vasospasm in humans.
Choroid plexus papillomas: long-term follow-up results in a surgically treated series
Authors: McGirr Stephen J. , Ebersold Michael J. , Scheithauer Bernd W. , Quast Lynn M. , Shaw Edward G. 
Published: May 2009

✓ The medical records and histological specimens from 26 patients with choroid plexus papillomas operated on at one institution were reviewed retrospectively. Four patients died perioperatively, and 21 of the remaining 22 patients were followed through March, 1986; the patient lost to follow-up review was last seen 14 years postoperatively. Of the 14 patients who underwent gross total removal of their tumor, one had a recurrence at 11 years postoperatively and two died in the perioperative period. Of the 12 patients who underwent subtotal removal of their tumor, two died in the perioperative period. The two patients who did not have radiation therapy postoperatively are free of apparent disease at 6 and 8 years after their operation. Eight patients underwent radiation therapy after subtotal removal of their tumor; four of these remain alive and well, and four have died of progressive disease.
The role of irradiation in the treatment of subtotally resected lesion remains controversial, but this therapy is thought to be indicated for recurrent disease after a surgical excision that is as complete as possible. Histopathologically, the presence of occasional mitotic figures, microscopic infiltration, ependymal differentiation, or mild to moderate atypia was not correlated with likelihood of complete resectability or tendency to recurrence.
Brain abscesses in neonates
Authors: Renier Dominique , Flandin Cécile , Hirsch Elizabeth , Hirsch Jean-François 
Published: May 2009

✓ Since the introduction of ultrasonography and computerized tomography (CT) scanning, brain abscesses are found more frequently in cases of neonatal meningitis and septicemia, particularly when the offending pathogen isProteus. Thirty cases of brain abscess in neonates are reported, 27 of which were caused byProteusspecies infections. Twenty infants had meningitis and 13 had septicemia. Most of the abscesses were enormous, and multiple abscesses were observed in 17 cases. The frontal region was involved in 22 cases (12 unilaterally and 10 bilaterally). The ventricles were enlarged on the first CT scan in 13 cases.The abscesses were treated by aspiration and antibiotics in 25 cases, and by antibiotics alone in five. A shunt for hydrocephalus was necessary in 14 infants. Four infants died, three from the initial illness and one from a shunt complication. Sixteen children have seizures. Subsequent intelligence quotient (IQ) testing was performed in 22 children: eight (36%) have an IQ at or above 80 and eight have an IQ of less than 60. In the 17 children followed for more than 2 years, the proportion with an IQ at or above 80 fell to 24% (four cases). The absence of initial seizures, sterile cerebrospinal fluid, normal ventricles on CT scans, and early aspiration of the abscess seem to be factors portending a better prognosis in terms of epilepsy and mental sequelae.
Pial arteriolar vessel diameter and CO2 reactivity during prolonged hyperventilation in the rabbit
Authors: Muizelaar J. Paul , van der Poel Henk G. , Li Zhongchao , Kontos Hermes A. , Levasseur Joseph E. 
Published: May 2009

✓ Hyperventilation reduces intracranial pressure (ICP) acutely through vasoconstriction, but its long-term effect on vessel diameter is unknown. In seven rabbits with a cranial window implanted 3 weeks earlier, the effect of prolonged hyperventilation on vessel diameter was studied. Anesthesia was maintained for 54 hours with a pentobarbital drip (1 mg/kg/hr). The pH, CO2, and HCO3− levels were measured in arterial blood and cisterna magna cerebrospinal fluid (CSF). The diameter of 31 pial arterioles was measured with an image splitter. After baseline measurements, pCO2 was reduced from 38 to 25 mm Hg and allowed to return to 38 mm Hg for 10 minutes every 4 hours.
There was an initial vasoconstriction of 13%, which progressively diminished by 3% every 4 hours. Thus, by the 20th hour, vessel diameters at a pCO2 of 25 mm Hg had returned to slightly above baseline values obtained at a pCO2 of 38 mm Hg. The temporary return of pCO2 to 38 mm Hg every 4 hours caused vasodilation: 12% at 4 hours, gradually increasing to 16% at 52 hours. Thus, at 52 hours, the vessel diameters were 105% of baseline at a pCO2 of 25 mm Hg and increased to 122% at a pCO2 of 38 mm Hg. Arterial pH had returned to baseline at 20 hours, and CSF pH had returned at 24 hours. Bicarbonate in blood and CSF remained decreased throughout the experiments. In three control experiments during which normocapnia was maintained, vessel diameter and pH and bicarbonate levels remained unaltered over the same period. The CO2 reactivity, tested by brief periods of hyperventilation every 4 hours, also did not change.
These results indicate that hyperventilation is effective in reducing cerebral blood volume for less than 24 hours and that it should be used only during actual ICP elevations. If used preventively, its effect may have worn off by the time ICP starts to rise for other reasons, and further decreases in pCO2 cannot be obtained. Moreover, the reduction in buffer capacity with lower bicarbonate renders the vessels more sensitive to changes in PaCO2. This could lead to more pronounced elevations in ICP during transient rises in PaCO2, such as during endotracheal suctioning in head-injured patients.
Malignant astrocytomas of the spinal cord
Authors: Cohen Alan R. , Wisoff Jeffrey H. , Allen Jeffrey C. , Epstein Fred 
Published: May 2009

✓ The authors review their experience with the operative management of 19 consecutive cases of malignant astrocytoma of the spinal cord. There was a male to female ratio of 1.1:1, and the median age of the population was 14 years (range 1 to 32 years). The median duration of symptoms prior to definitive diagnosis was 7 weeks. Radical excision was carried out in all cases, with 18 patients (95%) receiving radiotherapy and 10 patients (53%) receiving chemotherapy as well.
To date, 15 (79%) of the 19 patients in this series have died, with a median survival period of 6 months following surgery. No patient improved after operation. Hydrocephalus was present in 11 patients (58%), seven of whom underwent ventricular shunting procedures. Dissemination of disease was found in 11 patients (58%). Extraneural metastases did not occur in the absence of a ventricular shunt. The authors conclude that malignant astrocytomas of the spinal cord are heralded by a short history followed by rapid neurological deterioration and usually death. The rationale for operation is discussed, and an aggressive approach utilizing adjuvant therapy directed at the entire neuraxis is suggested.
Timing of operation for ruptured supratentorial aneurysms: a prospective randomized study
Authors: Öhman Juha , Heiskanen Olli 
Published: May 2009

✓ A total of 216 patients with a ruptured aneurysm of the anterior part of the circle of Willis were enrolled into this prospective randomized study of timing of the operation after aneurysmal subarachnoid hemorrhage (SAH). Only patients in clinical Grades I to III (according to the classification of Hunt and Hess) who were admitted and randomly assigned to a treatment group within 72 hours after the SAH were included in the trial. The patients were randomly assigned to one of three operation groups: acute surgery (AS: 0 to 3 days after the SAH; day of SAH = Day 0), intermediate surgery (IS: 4 to 7 days after the SAH), or late surgery (LS: 8 days to an indefinite time after the SAH). Three patients (4.3%) in the IS group and six patients (8.6%) in the LS group died before surgery was undertaken. At 3 months post-SAH, 65 patients (91.5%) from the AS group were classified as independent compared to 55 (78.6%) from the IS group and 56 (80.0%) from the LS group. The management mortality rate in the AS group was 5.6% compared to 12.9% in the LS group.
Of the 216 patients enrolled in the timing study, 159 were randomly assigned to an independent double-blind placebo-controlled trial of nimodipine in Grade I to III patients. A total of 79 patients received nimodipine and 80 placebo. When the nimodipine group and the no-nimodipine group (the 80 placebo-treated patients plus the 52 patients who were not entered into the nimodipine trial) were analyzed separately, a significant difference was seen in the outcome of the no-nimodipine group (dependent AS vs. dependent IS, p = 0.01). Nimodipine treatment was associated with a significant reduction of delayed ischemic deterioration (all operation groups combined, nimodipine vs. no nimodipine p = 0.01; LS with nimodipine vs. LS with no nimodipine, p = 0.03).
Plasmin-α2-plasmin inhibitor complex and α2-plasmin inhibitor in chronic subdural hematoma
Authors: Saito Kenichi , Ito Haruhide , Hasegawa Takeshi , Yamamoto Shinjiro 
Published: May 2009

✓ Levels of the plasmin-α2-plasmin inhibitor complex (PLN-A2PI complex) and α2-plasmin inhibitor (A2PI) were determined by enzyme-linked immunosorbent assay (ELISA) with monoclonal antibodies in 59 patients with 66 chronic subdural hematomas (SDH's). Normal concentrations of the PLN-A2PI complex and A2PI in plasma are below 0.8 µg/ml and 60.5 ± 16.1 µg/ml, respectively (mean ± 2 standard deviations). The hematoma fluid contained high concentrations of the PLN-A2PI complex (4.58 ± 2.60 µg/ml) and low concentrations of A2PI (10.32 ± 4.81 µg/ml), while both values in the plasma of 12 patients with chronic SDH's were within the normal range. This represents local hyperfibrinolytic activity in the hematoma.
Stuporous or comatose patients had higher PLN-A2PI complex levels than did the alert and the drowsy or disoriented patients. The layering type of hematoma as seen on computerized tomography scans showed the highest PLN-A2PI complex levels among five types of hematoma. In the fluid drained postoperatively from the subdural cavities of chronic SDH's, both the PLN-A2PI complex and A2PI levels decreased gradually in healing cases. In two patients with hematoma reaccumulation after surgery, both levels increased. The postoperative increase of the PLN-A2PI complex represents the recurrence of intermittent cycles of fibrinolysis, bleeding, coagulation, and hemostasis in the subdural space.
Tumor-infiltrating lymphocytes and histocompatibility antigens in primary intracranial germinomas
Authors: Saito Takafumi , Tanaka Ryuichi , Kouno Mituo , Washiyama Kazuo , Abe Satoshi , Kumanishi Toshiro 
Published: May 2009

✓ Subpopulations of tumor-infiltrating lymphocytes (TIL's) and the major histocompatibility complex (MHC) antigens of neoplastic cells were examined in three intracranial germinomas by an immunohistochemical method using monoclonal antibodies. About 70% to 80% of TIL's were T lymphocytes which were either infiltrating diffusely or in clusters, whereas 20% to 30% of TIL's were B lymphocytes which tend to cluster in tumor tissues. Examination of T lymphocyte phenotypes revealed both the cytotoxic/suppressor and helper/inducer T lymphocytes, as in other tumors. However, the existence of a considerable number of B lymphocytes in the TIL population was uncommon and seemed to be a characteristic feature of the intracranial germinoma, which might suggest a difference of host immune response to this neoplasm as compared to other tumors.
On examination of the MHC antigens, no MHC class I or II antigens in the neoplastic cells were stained, while positive staining for both antigens was seen in the TIL and stroma tissues. From these findings, it was suggested that the degree of TIL infiltration might not be correlated with the expression of MHC antigens in neoplastic cells in cases of primary intracranial germinoma.
The effect of interleukin-2 on the blood-brain barrier in the 9L gliosarcoma rat model
Authors: Alexander Joseph T. , Saris Stephen C. , Oldfield Edward H. 
Published: May 2009

✓ Carbon-14-labeled aminoisobutyric acid was used to determine local blood-to-tissue transfer constants in 22 Fischer rats with intracerebral 9L gliosarcomas that received either high-dose parenteral interleukin-2 (IL-2) or a control injection. In tumor and peritumoral tissue, the transfer constants in the IL-2-treated animals (89.6 ± 14.6 and 35.8 ± 6.0, respectively, mean ± standard error of the mean) were larger (p < 0.05) than in control animals (61.4 ± 6.4 and 14.6 ± 2.2, respectively). In contrast, in normal frontal and occipital tissue contralateral to the tumor-bearing hemisphere, there was no significant difference between the transfer constants in IL-2-treated and control animals. Furthermore, treatment of animals with IL-2 excipient caused no change in permeability as compared to animals treated with Hanks' balanced salt solution.
Parenteral injection of IL-2 increases blood-brain barrier disruption in tumor-bearing rat brain but does not increase the vascular permeability of normal brain. Methods to prevent this increased tumor vessel permeability are required before parenteral IL-2 can be used safely for the treatment of primary or metastatic brain tumors.
Civilian gunshot wounds to the brachial plexus
Authors: Kline David G. 
Published: May 2009

✓ Many gunshot wounds (GSW's) to the brachial plexus do not improve spontaneously with time and are therefore candidates for surgery. Over an 18-year period, 141 patients with GSW's were evaluated, 90 of whom were operated on; 75 of the surgical cases were followed for 2 years or more. Thirty operative patients had initial vascular repair, while eight required thoracotomies. Total plexus palsy was present in 19 of those selected for operation. The average interval between injury and operation was 17 weeks. Six patients required early operation for an expanding aneurysm with progressive neural loss. Persistent complete loss of function in the distribution of one or more elements and/or noncausalgic pain not managed by medications provided the major operative indications. Four patients required sympathectomies for causalgia.
Of 166 lesions in continuity believed to be complete, based on clinical examination and electromyography, 48 with preserved intraoperative nerve action potentials (NAP's) were spared resection or were treated with a split repair with excellent eventual results on a weighted grading system. By comparison, only seven of 55 elements believed to have incomplete loss or to be recovering did not have NAP's and required repair. Fifty-three of 98 lesions repaired by grafts and 18 of 26 wounds with suture repair recovered to a Grade 3 level or better. Most elements were in continuity but 14 were found “blown apart” and required repair, usually by grafting.
The best outcome was achieved with upper trunk and lateral and posterior cord lesions, but recovery occurred with some C-7 to middle trunk and medial cord to median repairs. Results with lower trunk and most medial cord lesions were poor unless early regeneration was proved by operative NAP's, in which case either neurolysis or split repair could be performed. Surgery is warranted for selected GSW's to the plexus.