bluuebunny/crossref_metadata_2025 huggingface dataset:
Silent intracerebral microhemorrhages in patients with ischemic stroke
Authors: Kwa Vincent I. H. , Franke Cees L. , Verbeeten Ben , Stam Jan ,   For the Amsterdam Vascular Medicine Group
Published: January 2005

We compared the frequencies of signs of old intracerebral hemorrhages on brain magnetic resonance imaging scans in 66 patients with ischemic stroke, 69 with myocardial infarction, and 86 with peripheral arterial disease (a total of 221 patients). Magnetic resonance imaging scans were independently assessed by two investigators without knowledge of clinical or laboratory data. In 31 patients (14%) we found local cerebral hemosiderin deposits. In 24 patients they were clinically silent. Hemosiderin deposits were significantly more frequent in patients with ischemic stroke (26%) than in patients with myocardial infarction (4%) or peripheral arterial disease (13%). Hemosiderin deposits were associated with cerebral white matter lesions (odds ratio, 5.3; 95% confidence interval, 2.5–12.4). The odds ratios were higher in patients with severe cerebral white matter lesions. Our findings support the hypothesis that cerebral vessels of patients with ischemic stroke are more prone to rupture than those of patients with other manifestations of atherosclerotic disease, which may explain the higher incidence of intracerebral hemorrhages when these patients are treated with oral anticoagulants. The microhemorrhages were associated with cerebral white matter lesions, which suggests that they are another manifestation of cerebral small‐vessel disease.
Evoked potential abnormality scores are a useful measure of disease burden in relapsing–remitting multiple sclerosis
Authors: O'Connor Paul , Marchetti Paul , Lee Liesly , Perera Maureen
Published: January 2005

Fifty patients with relapsing‐remitting multiple sclerosis were examined and studied with serial evoked potential and magnetic resonance imaging (MRI) measurements as part of a clinical trial. An evoked potential abnormality score (EPAS) for each testing session was calculated consisting of the total number of abnormal tests. The EPAS correlated well with Expanded Disability Status Scale (EDSS) at years 0, 1, and 2, with Spearman correlation coefficient scores of 0.68, 0.66, and 0.72, respectively. MRI lesion volume correlations ranged from 0.27 to 0.34 for the EDSS. EPAS are a potentially useful surrogate measure of clinical disability in relapsing‐remitting multiple sclerosis.
Search for varicella zoster virus in giant cell arteritis
Authors: Nordborg Claes , Nordborg Elisabeth , Petursdottir Vigdis , LaGuardia James , Mahalingam Ravi , Wellish Mary , Gilden Donald H.
Published: January 2005

Polymerase chain reaction and immunohistochemical analyses of formalin‐fixed temporal arteries from 10 pathologically verified cases of giant cell arteritis did not reveal varicella zoster virus antigen or DNA.
Expression of integrins in experimental autoimmune neuritis and guillain‐barré syndrome
Authors: Previtali S. C. , Archelos J. J. , Hartung H.‐P.
Published: January 2005

Integrins are a subclass of adhesion molecules that mediate cell–cell and cell–extracellular matrix interactions. Integrins influence transendothelial migration of lymphocytes and monocytes and are suitable targets for experimental immunotherapy. They are critically involved in the pathogenesis of autoimmune neuritis and abnormally expressed in human neuropathies. Also, the role of integrins in myelination, neurite outgrowth, and nerve regeneration suggests that they could be involved in the recovery phase of immune‐mediated neuropathies. We investigated by immunohistochemistry the expression of a number of integrin subunits during the course of experimental autoimmune neuritis (EAN). Results were compared with the human immune neuropathy Guillain‐Barré syndrome (GBS) and extended in vitro. Inflammation and demyelination in both EAN and GBS induced the down‐regulation of β4 integrin in Schwann cells (SCs), whereas loss of α2 was noted only in EAN. When axonal loss was present, SCs displayed α5integrin, in both EAN and GBS. In vitro, basal lamina and inflammatory cytokines modulated the expression of β4 in SCs, but they did not influence α2 and α5 expression. Finally, integrins were differentially expressed in blood vessels during EAN. In conclusion, the spatiotemporal changes in integrin expression may be used to characterize, stage, and better understand the pathogenesis and evolution of inflammation during GBS and EAN. This may help to establish useful, novel therapy for immune‐mediated neuropathies.
Ganaxolone, a selective, high‐affinity steroid modulator of the γ‐aminobutyric acid‐A receptor, exacerbates seizures in animal models of absence
Authors: Snead O. Carter
Published: January 2005

Ganaxolone (3α‐hydroxy‐3β‐methyl‐5α‐pregnan‐20‐one) is a novel neurosteroid which has anticonvulsant properties in a number of seizure models as well as the ability to enhance function of the γ‐aminobutyric acid‐A (GABAA) receptor complex via a neurosteroid binding site. The object of these experiments was to ascertain the efficacy of ganaxolone against absence seizures. Ganaxolone was assessed in the low‐dose pentylenetetrazol (PTZ) and the γ‐hydroxybutyric acid (GHB) model of absence seizures in rats. Ganaxolone pretreatment resulted in a significant prolongation of absence seizure in both the PTZ and GHB models. Further, ganaxolone in doses above 20 mg/kg alone produced bilaterally synchronous spike wave discharges (SWDs) associated with behavioral arrest. These data suggest that augmentation of GABAA receptor complex function by neurosteroids has the potential to result in or exacerbate absence seizures.
The phenotypic spectrum of CADASIL: Clinical findings in 102 cases
Authors: Dichgans M. , Mayer M. , Uttner I. , Brüning R. , Müller‐Höcker J. , Rungger G. , Ebke M. , Klockgether T. , Gasser T.
Published: January 2005

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an increasingly recognized autosomal dominant disorder that leads to cerebrovascular manifestations in early adulthood. This study delineates the phenotypic spectrum and the natural history of the disease in 102 affected individuals from 29 families with biopsy‐proven CADASIL. Recurrent ischemic episodes (transient ischemic attack [TIA] or stroke) were the most frequent presentation found in 71% of the cases (mean age at onset, 46.1 years; range, 30–66 years; SD, 9.0 years). Forty‐eight percent of the cases had developed cognitive deficits. Dementia (28%) was frequently accompanied by gait disturvance (90%), urinary incontinence (86%), and pseudobulbar palsy (52%). Thirty‐nine patients (38%) had a history of migraine (mean age at oneset, 26.0 years; SD, 8.2 years), which was classified as migraine with aura in 87% of the cases. Psychiatric disturbances were present in 30% of the cases, with adjustment disorder (24%) being the most frequent diagnosis. Ten patients (10%) had a history of epileptic seizures. To delineate the functional consequences of ischemic deficits, we studied the extent of disability in different age groups. The full spectrum of disability was seen in all groups older than age 45. Fifty‐five percent of the patients older than age 60 were unable to walk without assistance. However, 14% in this age group exhibited no disability at all. Kaplan‐Meier analysis disclosed median survival times of 64 years (males) and 69 years (females). An investigation of the 18 multiplex families revealed marked intrafamilial variations.
Prospective magnetic resonance imaging identification of focal cortical dysplasia, including the non—balloon cell subtype
Authors: Chan Stephen , Chin Steven S. , Nordli Douglas R. , Goodman Robert R. , DeLaPaz Robert L. , Pedley Timothy A.
Published: January 2005

The purpose of this study was to determine the role of high‐resolution T2‐weighted fast multiplanar inversion‐recovery (FMPIR) magnetic resonance (MR) imaging in detecting and delineating microscopic focal cortical dysplasia (FCD). We performed MR scans with FMPIR on 42 patients with suspected neocortical epilepsy. Ten MR studies were read prospectively as showing FCD; these case histories, electroencephalographic studies, and neuroimaging data were reviewed. Eight of these patients subsequently underwent focal cortical resection guided by intraoperative electrocorticography. The MR findings were correlated with pathological findings in these 8 patients. For purposes of radiological‐pathological correlation, the FCD lesions were divided into two classes. Radiological classification was based on the absence (type A) or presence (type B) of T2 prolongation of the subcortical white matter. Pathological grading as type I or type II was based on a previously described pathological grading system. Specific MR findings associated with FCD included focal blurring of the gray‐white matter interface (n = 9), thickening of the cortical ribbon (n = 7), and T2 prolongation of the subcortical white matter (n = 4). In 3 patients, the only MR finding that suggested FCD was localized blurring of the gray‐white matter junction. In 2 of these 3 patients, the MR diagnosis of FCD could be made only by FMPIR. FCD was confirmed histologically in 7 of 8 patients, with insufficient tissue for complete histopathological evaluation in 1 case. Radiological classification of FCD agreed with pathological classification in 5 of 7 cases. Correlation of MR findings with intraoperative electrocorticography results indicated that the MR study localized the epileptogenic lesion correctly in 8 of 8 cases. Scalp ictal electroencephalographic studies localized the epileptogenic lesion in 5 of 8 cases; positron emission tomographic scans were focally abnormal in 3 of 3 cases. FMPIR MR imaging permitted accurate diagnosis and localization of FCD in all patients with pathologically proved FCD. MR identification of FCD aided presurgical planning and intraoperative management of these patients.
Enhanced oxygen radical production in a transgenic mouse model of familial amyotrophic lateral sclerosis
Authors: Liu Rugao , Althaus John S. , Ellerbrock Brenda R. , Becker David A. , Gurney Mark E.
Published: January 2005

Mutations of the SOD1 gene encoding copper/zinc superoxide dismutase (CuZnSOD) cause an inherited form of amyotrophic lateral sclerosis. When expressed in transgenic mice, the same SOD1 mutations cause progressive loss of spinal motor neurons with consequent paralysis and death. In vitro biochemical studies indicate that SOD1 mutations enhance free radical generation by the mutant enzyme. We investigated those findings in vivo by using a novel, brain‐permeable spin trap, azulenyl nitrone. Reaction of azulenyl nitrone with a free radical forms a nitroxide adduct that then fragments to yield the corresponding azulenyl aldehyde. Transgenic mice expressing mutant SOD1‐G93A show enhanced free radical content in spinal cord but not brain. This correlates with tissue‐specific differences in the level of transgene expression. In spinal cord, the increase in free radical content is in direct proportion to the age‐dependent increase in mutant human CuZnSOD expression. This increase precedes motor neuron degeneration. The higher level of human CuZnSOD expression seen in spinal cord compared with brain, and consequent difference in free radical generation, provides a basis for understanding the selective vulnerability of the spinal cord in this disease model.
Electrophysiological classification of guillain‐barré syndrome: Clinical associations and outcome
Authors: Hadden R. D. M. , Cornblath D. R. , Hughes R. A. C. , Zielasek J. , Hartung H.‐P. , Toyka K. V. , Swan A. V. ,   The Plasma Exchange/Sandoglobulin Guillain‐Barré Syndrome Trial Group
Published: January 2005

We performed electrophysiological and serological testing within 15 days of symptom onset on 369 patients with Guillain‐Barré Syndrome (GBS) enrolled in a trial comparing plasma exchange, intravenous immunoglobulin, and both treatments. Patients were classified into five groups by motor nerve conduction criteria; 69% were demyelinating, 3% axonal, 3% inexcitable, 2% normal, and 23% equivocal. Six of 10 (60%) patients with axonal neurophysiology had had a preceding diarrheal illness compared with 71 of 359 (20%) in other groups. Antiganglioside GM1 antibodies were present in a higher proportion of patients with axonal physiology or inexcitable nerves than other patients. The number dead or unable to walk unaided at 48 weeks was greater in the group with initially inexcitable nerves (6 of 12, 50%) compared with the rest (52 of 357, 15%), but was not significantly different between the axonal (1 of 10, 10%) and demyelinating (44 of 254, 17%) groups. Sensory action potentials and clinical sensory examination were both normal in 53 of 342 (16%) patients, and these “pure motor GBS” patients were more likely than other GBS patients to have IgG antiganglioside GM1 antibodies and to have had preceding diarrhea but had a similar outcome. The axonal group was more likely than other groups to have normal sensory action potentials. The outcomes in response to the three treatments did not differ in any subgroup (including patients with pure motor GBS or preceding diarrhea) or any neurophysiological category.
Somatic and limbic cortex activation in esophageal distention: A functional imaging study
Authors: Binkofski F. , Schnitzler A. , Enck P. , Frieling T. , Posse S. , Seitz R. J. , Freund H.‐J.
Published: January 2005

Little is known about the cerebral representations of visceral sensations in humans. Using functional magnetic resonance imaging (fMRI), we mapped the cortical areas of the human brain that were activated by mechanical stimulation of the esophagus in 5 healthy volunteers. Stimulation probes were placed into the distal part of the esophagus and inflated to produce a local distention. The cerebral activation pattern was related to the strength and quality of the stimulus. The weakest stimulus accompanied by a well‐localized albeit weak retrosternal sensation activated only the parietal opercular cortices, probably including the secondary somatosensory cortex (SII). Additional activation of the primary sensorimotor cortex (SI) at the level of the face and mouth representation as well as of the right premotor cortex was found during repetitive distention of the esophagus at 0.5 Hz. Repetitive stimulation at 1 Hz additionally activated the insulabilaterally. The strongest distention stimulus, which caused a painful retrosternal sensation, resulted in an activation of the anterior cingulate cortex. Our findings demonstrate that SII is the primary cortical target of visceral afferents originating in the esophagus. Limbic structures become engaged when the visceral senstion is unpleasant or painful.
Protein modification by the lipid peroxidation product 4‐hydroxynonenal in the spinal cords of amyotrophic lateral sclerosis patients
Authors: Pedersen Ward A. , Fu Weiming , Keller Jeffrey N. , Markesbery William R. , Appel Stanley , Smith R. Glenn , Kasarskis Edward , Mattson Mark P.
Published: January 2005

We report increased modification of proteins by 4‐hydroxynoneal (HNE), a product of membrane lipid peroxidation, in the lumbar spinal cord of sporadic amyotrophic lateral sclerosis (ALS) patients versus that of neurologically normal controls. By immunohistochemistry, HNE‐protein modification was detected in ventral horn motor neurons, and immunoprecipitation analysis revealed that one of the proteins modified by HNE was the astrocytic glutamate transporter EAAT2. Given that the function of proteins modified by HNE can be severely compromised as previously demonstrated for glutamate transporters in cortical synaptosome preparatations, our findings suggest a scenario in which oxidative stress leads to the production of HNE, impairment of gluatmate transport, and excitotoxic motor neuron degeneration in ALS.
Imaging epileptogenic tubers in children with tuberous sclerosis complex usingα‐[11C]Methyl‐L‐tryptophan positron emission tomography
Authors: Chugani Diane C. , Chugani Harry T. , Muzik Otto , Shah Jagdish R. , Shah Aashit K. , Canady Alexa , Mangner Thomas J. , Chakraborty Pulak K.
Published: January 2005

Several reports have indicated that cortical resection is effective in alleviating intractable epilepsy in children with tuberous sclerosis complex (TSC). Because of the multitude of cortical lesions, however, identifying the epileptogenic tuber(s) is difficult and often requires invaise intracranial electroencephalographic (EEG) monitoring. As increased concentrations of serotonin and serotonin‐immunoreactive processes have been reported in resected human epileptic cortex, we used α‐[11C]methyl‐L‐tryptophan ([11C]AMT) position emission tomography (PET) to test the hypothesis that serotonin synthesis is increased interictally in epileptogenic tubers in patients with TSC. Nine children with TSC and epilepsy, aged 1 to 9 years (mean, 4 years 1 month), were studied. All children underwent scalp video‐EEG monitoring, PET scans of glucose metabolism and serotonin synthesis, and EEG monitoring during both PET studies. [11C]AMT scans were coregistred with magnetic resonance imaging and with glucose metabolism scans. Whereas glucose metabolism PET showed multifocal cortical hypometabolism corresponding to the locations of tubers in all 9 children, [11C]AMT uptake was increased in one tuber (n = 3), two tubers (n = 3), three tubers (n = 1), and four tubers (n = 1) in 8 of the 9 children. All other tubers showed decreased [11C]AMT uptake. Ictal EEG data available in 8 children showed seizure onset corresponding to foci of increased [11C]AMT uptake in 4 children (including 2 with intracranial EEG recordings). In 2 children, ictal EEG was nonlocalizing, and in 1 child there was discordance between the region of increased [11C]AMT uptake and the region of ictal onset on EEG. The only child whose [11C]AMT scan showed to no regions of increased uptake had a left frontal seizure focus on EEG; however, at the time of his [11C]AMT PET scan, his seizures had come under control. [11C]AMT PET may be a powerful tool in differentiating between epileptogenic and nonepileptogenic tubers in patients with TSC.
β‐Trace protein in cerebrospinal fluid: A blood–CSF barrier–related evaluation in neurological diseases
Authors: Tumanin Hayrettin , Nau Roland , Felgenhauer Klaus
Published: January 2005

β‐Trace protein concentrations in cerebrospinal fluid (CSF) and serum from 113 patients with variuos neurological diseases and 65 controls were determined with a sensitive and specific immunonephelometric assay. In adult control patients, β‐trace concentrations were 14.6 ± 4.6 mg/L in CSF and 0.46 ± 0.13 mg/L in serum, that is 32‐fold higher in CSF. β‐trace levels in CSF correlated with age as well as with the albumin CSF/serum ratio (QA1b), which is considered a measure for blood‐CSF barrier function. The relationship between CSF β‐trace levels and elevated QA1b values was studied in various neurological diseases with CSF protein increase. In spinal canal stenosis, CSF β‐trace (mean = 29.5 ± 10.5 mg/L) correlated positively with increasing QA1b values. In bacterial meningitis, CSF β‐trace (mean = 8.7 ± 3.9 mg/L) remained invariant to changes of QA1b values. In Guillain‐Barre syndrome, CSF β‐trace (mean = 14.4 ± 6.8 mg/L) was below the QA1b‐dependent reference range. In multiple sclerosis and viral meningoencephalitis, β‐trace levels were within the reference range. β‐Trace concentration in CSF can be used in conjunction with QA1b to distinguish between different neurological pathologies associated with CSF protein increase.
Risk of unprovoked seizure after acute symptomatic seizure: Effect of status epilepticus
Authors: Hesdorffer Dale C. , Logroscino Giancarlo , Cascino Gregory , Annegers John F. , Hauser W. Allen
Published: January 2005

We asked whether acute symptomatic status epilepticus (SE) increases the risk for subsequent unprovoked seizure compared with less prolonged acute symptomatic seizure. We also explored whether the risk of unprovoked seizure differs by cause. We ascertained all first episodes of acute symptomatic seizure among residents of Rochester, Minnesota, through the Rochester Project's records‐linkage system. Information was collected on seizure duration, age, sex, cause, and subsequent unprovoked seizure. At 10 years of follow‐up, the risk of unprovoked seizure was 41% for those with acute symptomatic seizure with SE and 13% for those without SE. Controlling for age, sex, and cause, SE increased the risk for subsequent unprovoked seizure 3.3‐fold (95% confidence interval, 1.8–6.1) compared with brief acute symptomatic seizures. Among patients with SE, the risk of unprovoked seizure was increased 18.8‐fold for patients with anoxic encephalopathy, 7.1‐fold for patients with a structural cause, 3.6‐fold for patients with a metabolic cause. The increased risk for unprovoked seizure after SE compared with shorter seizures may be due to SE being a marker for severity of injury, damage caused by SE, or a biological substrate associated with the tendency to experience SE.
The mitochondrial DNA A8344G mutation in leigh syndrome revealed by analysis in paraffin‐embedded sections: Revisiting the past
Authors: Santorelli F. M. , Tanji K. , Shanske S. , Krishna S. , Schmidt R. E. , Greenwood R. S. , DiMauro S. , de Vivo D. C.
Published: January 2005

In 1975, we presented the results of a study on a family with a constellation of features that included a chronic spinocerebellar syndrome, neuropathologically proven Leigh syndrome, and sudden death in infancy or childhood affecting several members over three generations. Inheritance was thought to be autosomal dominant. Twenty years later, we reinterpreted the inheritance pattern as maternal. Mitochondrial DNA (mtDNA) extracted from paraffin‐embedded brain samples from the proband revealed the A8344G myoclonic epilepsy and ragged‐red fiber (MERRF) mutation as the molecular basis for this multifaceted neurological syndrome. This re‐evaluation of archival material is an instructive example of “medical archeopathology”.
Utility of anti‐Hu antibodies in the diagnosis of paraneoplastic sensory neuropathy
Authors: Molinuevo Jose Luis , Graus Francesc , Serrano Carmen , Reñe Ramón , Guerrero Antonio , Illa Isabel
Published: January 2005

Anti‐Hu antibodies (Hu‐Abs) were positive in 40 patients with paraneoplastic sensory neuropathy (PSN) and in 1 patient with idiopathic sensory neuropathy in a series of 126 patients who presented with clinical features suggestive of PSN. The specificity of Hu‐Abs was 99% and the sensitivity was 82%. Nine (18%) PSN patients were Hu‐Ab–negative, and their sera did not harbor other specific anti‐neuronal of anti‐ganglioside antibodies. Small cell lung carcinoma (SCLC) was the leading neoplasm in the Hu‐Ab–positive (79%) and Hu‐Ab–negative (44%) groups. This study confirms the value of Hu‐Abs for the diagnosis of PSN and SCLC and also emphasizes that in patients with possible PSN, the absence of Hu‐Abs does not exclude cancer, particularly in those patients with risk factors for SCLC.
Orbital shaker technology for the cultivation of mammalian cells in suspension
Authors: Muller Natalie , Girard Philippe , Hacker David L. , Jordan Martin , Wurm Florian M.
Published: January 2005

For large‐scale applications in biotechnology, cultivation of mammalian cells in suspension is an essential prerequisite. Typically, suspension cultures are grown in glass spinner flasks filled to less than 50% of the nominal volume. We propose a superior system for suspension cultures of mammalian cells based on orbital shaker technology. We found that “square‐shaped” bottles (square bottles) provide an inexpensive but efficient means to grow HEK‐293 EBNA and CHO‐DG44 cells to high density. Cultures in agitated 1‐L square bottles exceeded the performance of cultures in spinner flasks, reaching densities up to 7 × 106 cells/mL for HEK‐293 EBNA cells and 5 × 106 cells/mL for CHO‐DG44 cells in comparison to (2.5–4) × 106 cells/mL for cultures of the same cells grown in spinner flasks. For 1‐L square bottles, optimal cell growth and viability were observed with a filling volume of 30–40% of the nominal volume and an agitation speed of 130 rpm at a rotational diameter of 2.5 cm. Transient reporter gene expression following gene delivery by calcium phosphate–DNA co‐precipitation was the same or slightly better for HEK‐293 EBNA cells grown in square bottles as compared to spinner flasks. Reductions in cost, simplified handling, and better performance in cell growth and viability make the agitated square bottle a new and very promising tool for the cultivation of mammalian cells in suspension. © 2004 Wiley Periodicals, Inc.
Quantitative chemical changes in the human brain during growth
Authors: Macarthur C. G. , Doisy E. A.
Published: January 2005

During growth the proteins, phosphatids, sulphatids, cerebrosides, cholesterol, and total solids increase in percentage amounts. There is but slight change in the percentage of extractives, either organic or inorganic. Water decreases regularly to maturity.
Experimental innervation of muscles by the central ends of afferent nerves (establishment of a one‐neurone connection between receptor and effector organ), with functional tests
Authors: Weiss Paul
Published: January 2005

In adult toads the central end of the ninth or tenth dorsal root was disnonnected from the spinal cord and inserted instead into a denervated muscle which has previously been tranplated to the back. In this way a direct connection between peripheral sense organs and muscle fibers has been achieved by a single sensory neurone (‘mono‐neuronal’ connecttion), eliminating the central nervous system as intermediary between receptor and effector organs.
The cortical area concerned with coordinated walking in the rat
Authors: Maier Norman R. F.
Published: January 2005

Cortical lesions in the rat do not produce paralysis, but they may greatly handicap its performance when running on narrow poles. To determine whether or not this handicap is due to the loss of some particular area, sixy‐six rats were subjected to various patterns of lesions and then tested to determine their skill on narrow poles. The performance of eacht rat was rated with 0 (no handicap), 1, 2, or 3, according to the degree of diability in walking on the poles.
Electroencephalogram of the chicken recorded from the skull under various conditions
Authors: Ookawa Takanori , Gotoh Jiro
Published: January 2005

Electroencephalographic studies were carried out on chickens to determine the normal electroencephalogram (EEC) patterns from wakefulness to sleep and the effect of anesthesia. Sixteen electrodes were fixed to the frontal and parietal bones. EEC was recorded under unstressed condition.

In the excited state, fast waves of 30 to 60 cps and of low amplitude were predominant. In the resting period, these waves shifted to slower ones of 14 to 24 cps, the amplitude remaining low as in the excited state. As the bird fell asleep, three main stages could be distinguished according to the correlation between the EEC patterns and behavioral states. Under ether anesthesia, four stages could be distinguished according to the EEC patterns and the responsiveness to afferent stimuli. By increasing the dose of nembutal, the correlation between the EEC pattern and the depth of anesthesia was studied.

The “spindle burst”, or “barbiturate burst,” and the “fast wave” shown in mammals by the injection of barbiturates were not observed in the chicken.
An autoradiographic study on the origin and fate of the sub‐pial glioblast in the embryonic chick spinal cord
Authors: Fujita Setsuya
Published: January 2005

Gliogenesis in the spinal cord was studied in chick embryos ranging in age from 3 to 14 days of incubation using H3‐thymidine autoradiography. It has been reported by the author that the neuron production of the spinal cord begins on the third day and ends at the eighth day of incubation. At eight days of incubation glioblasts with small dark round nuclei first appear in the sub‐pial region. Using the selective labeling technique with H3‐thymidine the author demonstrated that no transition exists from pial cells to sub‐pial glioblasts. The glioblasts are produced from the matrix cells by their migration and transformation. These glioblasts mature into neuroglia (oligodendroglia and astrocytes), as development proceeds. The suggestion that the stage of neuroglia differentiation follows that of neuron production in development of the central nervous system has been reconfirmed.
Effect of visual deprivation on the optic centers of growing and adult mice
Authors: Gyllensten Lars , Malmfors Torbjörn , Norrlin Marie‐Louise
Published: January 2005

The thickness of the visual cortex, the diameter of cell nuclei and the mean volume of internuclear material per nucleus in the visual cortex, geniculate bodies and superior colliculi were determined in growing and adult mice. The influence of prolonged stay in complete darkness was investigated.

In the visual cortex of normal mice, a peak in nuclear size occurred 20–30 days after birth, followed by a peak in relative volume of internuclear material.

In growing mice, reared in darkness from birth, a highly significant decrease in relative volume of internuclear material occurred in all visual centers. The decrease was greatest in the geniculate bodies and greater in the granular and supragranular layers of the cortex than in the infragranular. In the cortex, the decrease was most pronounced after two months and became less pronounced during prolonged stay in darkness. No similar normalization was observed in subcortical visual centers. In the same mice, visual deprivation caused a highly significant decrease in the thickness of the visual cortex and in the diameter of its cell nuclei. The decrease in nuclear diameter was greater in the granular and supragranular than in the infragranular layers of the cortex and exhibited a similar normalization during prolonged stay in darkness as the decrease in relative volume of internuclear material.

In adult mice, visual deprivation caused decrease in internuclear material.
An experimental study of the accessory optic system and of other optic fibers in the opossum, Didelphis Virginiana
Authors: Giolli Roland A.
Published: January 2005

A study of experimental degeneration of the accessory optic system in a primitive mammal, the opossum, was undertaken in order the clarify several points regarding fiber organization and to allow comparisons to be made with this system in more advanced mammals and non‐mammalian vertebrates. The other portions of the optic system were also studied but not in great detail, since the findings were in basic agreement with those of Bodian ('37) in opossum. An eye was enucleated in each of five opossums which was sacrificed 7–12 days later. The Nauta‐Gygax technique was used to show that in opossum the accessory optic system consists essentially of one pair of tracts and terminal nuclei. Fibers of this system cross in the optic chiasma and leave the optic tract midway between the chiasma and the lateral geniculate nucleus to course caudally on the surface of the medial third of the cerebral peduncle. They intermingle with the fibers of the superficial division of the tractus geniculatus descendens and then enter the nucleus of the transpeduncular tract to terminate.

The findings on the structure of the accessory optic system in opossum are in basic agreement with those in reptiles and birds. Comparison with studies in more advanced mammals indicates that this system has undergone striking changes in the topographical organization of its fibers.
Autoradiographic and histological evidence of postnatal hippocampal neurogenesis in rats
Authors: Altman Joseph , Das Gopal D.
Published: January 2005

In the autoradiograms of young rats injected with thymidine‐H3 many of the granule cells of the dentate gyrus were found labeled. The number of labeled cells declined rapidly with increased age at the time of injection. Histological studies showed the presence in young rats of a large germinal matrix of mitotic cells in the ependymal and subependymal layers of the third and lateral ventricles. The areal extent and cell population of this germinal pool declined rapidly from birth on, with a transient rise with a peak at about 15 days. During this latter period the number of “undifferentiated” cells near the granular layer of the dentate gyrus showed a rapid rise with a subsequent decline. The decline in the number of “undifferentiated” cells was accompanied by a rise in the number of differentiated granule cells. Cell counts in homologous parts of the dentate gyrus indicated a six‐fold increase in the number of differentiated granule cells from birth to three months. We postulated that undifferentiated cells migrate postnatally from the forebrain ventricles to the hippocampus where they become differentiated. The possible functional significance of delayed hippocampal neurogenesis is discussed with reference to our finding of incorporation of testosterone‐H3 by cells of the hippocampus, implicating that they may function as receptors of gonadal hormones.
Distribution of corpus callosum and anterior commissure in cat and raccoon
Authors: Ebner Ford F. , Myers Ronald E.
Published: January 2005

The distribution of the forebrain commissures was studied using the Nauta‐Gygax silver technique. Following total forebrain commissure transection in the cat the striate cortex or visual area I was remarkably free of degenerating fibers, while peristriate or visual area II showed dense degeneration. Somatic sensory arm and distal hindlimb areas appeared degeneration free while proximal leg and face areas revealed heavy degeneration. The somatic motor area of the anterior sigmoid gyrus contained dense numbers of degenerating fibers. The auditory areas of ectosylvian gyrus showed moderate degeneration over their entire surface except the most ventrally situated cortical areas which were degenerated free. Fibers from the corpus callosum also terminated in the dorsolatearal portions of the head of the caudate nucleus. The anterior limb of anterior commissure distributed mainly to the inner granular layer of the olfactory bulb. In addition, it disseminated considerable numbers of fibers in the anterior olfactory nucleus. The accessory olfactory bulb was degeneration free. The distribution of the forebrain commissures in the raccoon was very similar to the cat. The outstanding feature of the commissural pattern in the raccoon was the total absence of degenerating fibers in the lobular complex relating to the digits of the forepaw.
Distribution of optic fibers in the cat
Authors: Singleton Mary C. , Peele Talmage L.
Published: January 2005

This study undertook to investigate pathways and connections of optic tract fibers in the pulvinar, hypothalamus, ventral lateral geniculate, pretectal region and superior colliculus.

Thirty‐five adult cats were utilized — 28 experimental subjects and seven controls. The right eye was removed and the cats allowed to survive for periods from three to 61 days. The chief method of investigation was the silver impregnation technique of Nauta‐Gygax ('54), supplemented by Marchi and luxol‐blue cresyl‐fast‐violet methods.

Study of fiber patterns of degeneration in serial sections of the Nauta‐Gygax preparations revealed no preterminal axonal degeneration in the hypothalamus or pulvinar. Portions of a completely crossed accessory optic tract as described by Hayhow ('59) were identified. Preterminal degeneration of fine collaterals of the larger optic fibers was found in the dorsal one‐third of the lateral portion of the ventral lateral geniculate. Large areas of preterminal degeneration and many fibers of passage were observed in the pretectal region. Localized areas of pretermimal degeneration in this region were interpreted as belonging to the pretectal nucleus and to the nucleus of the optic tract. A large number of fine optic fibers was found terminating in the superficial stratum opticum of the superior colliculus. Two areas of preterminal degeneration lateral to the colliculus were interpreted as extension of the pretectal nucleus and as the nucleus olivaris colliculi.
Cellular localization of monoamines in the area postrema of certain mammals
Authors: Fuxe Kjell , Owman Christer
Published: January 2005

The area postrema was studied using a highly sensitive and specific fluorescence microscopical method for the demonstration of certain biogenic monoamines. In all the species studied (rat, guinea‐pig, rabbit, cat, dog, monkey) there occur small nerve cells containing a primary catecholamine. A varying number of catecholamine‐storing nerve terminals can be demonstrated in all species. Many — if not all — of these seem to derive from catecholamine axons running in abundance just outside the area postrema.

Against the background of earlier findings (Vogt, '54; Amin, Crawford and Gaddum, '54) of high levels of noradrenaline and 5‐hydroxytryptamine thought to be present in glial cells in this organ it is concluded that these levels are not in accordance with the relatively small number of monoamine‐containing structures demonstrated in area postrema. The explanation for this is in all probability that the area postrema tissue taken for biochemical determinations have been contaminated with surrounding brain tissue, very rich in catecholamine and 5‐HT containing terminals.

There is discussed in conclusion the possibility of adrenergic mechanisms being involved in the reflex path of central emesis.
Hematic and fluid barriers in the optic nerve
Authors: Rodriguez‐Peralta Lorenzo A.
Published: January 2005

Hematic and fluid barriers in the optic nerve have been studied by tracing the in vivo penetration of diaminoacridines in tissue nuclei and tissue fluids. Diaminoacridines were administered at non‐toxic doses and were detected by the fluorescence they produced when properly excited.

Diaminoacridine concentrations of 10−6M or higher in circulating blood failed to penetrate into tissues and fluids protected by hemato‐encephalic or hemato‐ocular barriers. However, fluoresence was found in: (a) optic nerve dura mater including the mesothelium lining its inner surface, but not in the subjacent arachnoid, pia, or cerebrospinal fluid; (b) all orbital and dural vessel walls, including their endothelium, but not in the pial nor optic nerve vessel walls; (c) choroid, sclera, and Kuhnt's tissue, but not in the optic nerve.

Diaminoacridine concentrations of 10−6M in cerebrospinal fluid produced fluorescence in optic nerve tissues and vessels, including their endothelium, and meninges, including dural mesothelium, but not in retina or vitreous. Similar concentrations in the vitreous showed fluorescence in the retina and optic nerve head tissues, but not farther in the optic nerve.

Thus: (a) there is a blood‐optic nerve barrier; (b) this barrier is located in the mesothelium lining the inner dural surface, in pial and optic nerve vessels endothelium, and Kuhnt's tissue; (c) endothelium and mesothelium showed one‐way permeability; (d) there is a vitreous optic‐nerve barrier preventing passage of fluids from optic nerve to vitreous or vice versa.
Histogenesis of the nuclei griseum pontis, corporis pontobulbaris and reticularis tegmenti pontis (Bechterew) in the mouse an autoradiographic study
Authors: Pierce Elizabeth Taber
Published: January 2005

By means of autoradiography the time, site of origin and migration pathways of neuroblasts destined for three nuclei in the hindbrain of the mouse have been determined. The cells of the nuclei griseum pontis and corporis pontobulbaris arise on gestation days 12 through 16 in the rhombic lip from the obex to the lateral recess. Most cells migrate within 48 hours via the pontobulbar body to the base of the pons to form the nucleus griseum pontis; some migrate only a short distance along the pathway and collectively form the nucleus corporis pontobulbaris. Most cells of the nucleus reticularis tegmenti pontis (Bechterew) arise in the primitive basal ependymal plate of the pons on gestation days 12 and 13 and migrate ventrally into the tegmentum. Some probably arise at the rhombic lip and migrate via the pontobulbar body to the base of the pontine flexure where they turn dorsally into the tegmentum.
Some olfactory pathways in the rabbit brain
Authors: Scalia Frank
Published: January 2005

The degeneration pattern in the rabbit following transection of the olfactory bulb or peduncle at various levels was studied by the Laidlaw method of Nauta. Degenerating axons were observed in the crossing of the anterior limb of the anterior commissure and in the lateral olfactory tract following olfactory bulb lesions which did not damage the anterior olfactory nucleus. Evidence was found for termination of the olfactory tract fibers over all parts of the anterior olfactory nucleus, the rostral and lateral parts of the olfactory tubercle, the anterior continuation of the hippocampus, the nucleus of the lateral olfactory tract, and the prepyriform areas 1, 2, and 3, the periamygdaloid areas 1, 2, part of 3, and 5, and the entorhinal axeas 1, 2, and 4 of Maximillian Rose. When the anterior olfactory nucleus was damaged degeneration was found in the contralateral olfactory bulb and anterior olfactory nucleus and parts of the ipsilateral neocortex adjacent to the rhinal fissure, limbic system (medial septal nucleus and anterior continuation of the hippocampus), pyriform lobe cortex, and lateral preoptic area. The results differ in particulars from those of previous investigators.
The ultrastructure and innervation of rat vibrissae
Authors: Patrizi G. , Munger B. L.
Published: January 2005

The innervation of rat vibrissae has been studied by light and electron microscopy. Nerve fibers enter the external root sheath and become associated with Merkel cells. Merkel cells are specialized sheath cells containing many secretory granules apposed to the neurite. These secretory granules are PAS‐positive and diastase‐resistant in light microscopic preparations. The neurite at the level of the Merkel cell is expanded and contains masses of mitochondria. As contrasted to nerve fibers in glabrous skin, the neurite does not penetrate deeply into the external root sheath but appears to terminate at the level of the Merkel cells. The neurite‐Merkel cell complex is interpreted as representing a mechanoreceptor.
Electron microscopy of the effect of gram‐negative endotoxin on the blood‐brain barrier
Authors: Carlyle Clawson C. , Francis Hartmann J. , Vernier Robert L.
Published: January 2005

Studies with the light microscope (Am. J. Path., 34: 631, '58) indicated that an injection of endotoxin into the carotid artery of a rabbit alters the blood‐brain barrier allowing the distribution of subsequently injected colloidal iron throughout the cerebral cortex. The present investigation by electron microscopy determined the distribution of the colloidal iron oxide in the normal and endotoxin altered cerebral capillaries of rabbits. Four hours prior to the intracarotid injection of saccharated iron oxide the animal received an injection via the same artery of either 50 μg gram‐negative endotoxin or a control dose of normal saline. The animals were sacrificed at times from 15 minutes to two hours after the injection of iron oxide and samples of the cerebral cortex were processed for electron microscopy by routine methods. In those animals that did not receive endotoxin, the colloidal iron was limited to the lumen of the cerebral capillaries and occasional large endothelial vacuoles. None of the iron was found in the endothelial pinocytotic vesicles. In the endotoxin animals the iron oxide particles were found in quantity in the capillary endothelium phagosomes, the basement membrane, and in astrocytes and their processes. The fine structure of the cerebral capillary is reviewed and evidence is presented in support of the hypothesis that the barrier mechanism for colloidal tracers lies in a unique property of the brain's endothelial pinocytotic vesicles.
The ultrastructural characterization of macroglial cell types
Authors: Wendell‐Smith C. P. , Blunt M. J. , Baldwin F.
Published: January 2005

In the prelaminar region of adult cat optic nerve, silver impregnation revealed a macroglial cell population consisting solely of small fibrous astrocytes. Electron microscopically the cells were characterized by abundant processes containing closely packed filaments and occasional glycogen granules; their perikarya contained few organelles, glycogen particles were conspicuous but not abundant, and their cytoplasmic and nucleoplasmic matrices were of low density.

The laminar region contained typical fibrous astrocytes. These cells were characterized by similar processes and matrices but their perikarya contained filaments and were richer in organelles whose orientation was primarily radial.

The postlaminar region contained both astrocytes and oligodendrocytes. The latter were identified as cells characterized by the absence of filaments and glycogen, the presence of canaliculi, dense cytoplasmic and nucleoplasmic matrices and perikarya very rich in organelles, whose orientation was primarily circumferential.

The presence of filaments and/or glycogen on the one hand, and of dense matrices on the other hand, seemed to be mutually exclusive and provided diagnostic criteria for astrocytes and oligodendrocytes respectively. Bivalent forms were not seen. Cells usually identified as microglia were not seen.

The relationship between astrocytes and finely myelinated nerve fibers in the lamina cribrosa indicates a sheath‐supporting role. Astrocytes are probably generally concerned with the isolation and insulation of neurons and their processes. Oligodendrocytes may be concerned with the energetic support of neurons and their processes.
A study of Golgi preparations from the dorsal lateral geniculate nucleus of the adult cat
Authors: Guillery R. W.
Published: January 2005

Four cell types are distinguishable in the lateral geniculate nucleus. The largest (class 1) have their dendrites oriented in relation to the plane of the laminae. The dendrites cross laminar borders freely and bear many fine spines. Class 2 cells show less orientation of their dendrites. These dendrites bear clusters of grape‐like appendages close to the branching points and fine spines on their peripheral segments. Only the peripheral segments cross laminar borders. The smallest (class 3) cells have long stalked appendages and give rise to intrinsic axons which ramify close to the perikaryon. Cell classes 1 and 2 occur in laminae A and A1, with class 1 cells mainly concentrated between laminae. Class 3 cells occur in all major laminae. Class 4 cells, with long smooth dendrites oriented parallel to the lamina, lie in lamina B.

Two types of extrinsic axon are seen. Type I axons give off many short simple terminal collaterals which often innervate more than one lamina. These are regarded as extra‐retinal afferents. Type II axons (probably retinal afferents) have complex flower‐like terminals and each axon innervates only one lamina.

Contacts between several type II axons and two or more grape‐like clusters occur in laminae A and A1. In lamina B finer type II axons form complex overlapping terminal nests around the dendrites of class 4 cells.