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PubMedDate not supplied

[Blood-brain barrier disorders and changes in intracranial pressure in cats with surgical brain wound following sudded brain decompression].

The condition of the blood-brain barrier and changes in intracranial pressure were studied in cats with surgical brain wounds and after sudded decompression. It was found that evident disturbances of the barrier function appeared only 48 hours after removal of brain tissue and were affecting mainly the white matter. Sudden decompression led to disturbances of blood-brain function when it was proceded by at least 2 hours of epidural compression. Changes developed in the cortex and basal ganglia. After 48 hours from tissue removal a significant rise of pressure was observed in the cisterna magna to a mean value of 11.5 mm Hg. Decompression caused a fall of cerebrospinal pressure, often below zero, and this was followed by a rise to values significantly exceeding the level before decompression.

Animals↗
PubMed1991

The epidemiology of headache among children with brain tumor. Headache in children with brain tumors. The Childhood Brain Tumor Consortium.

In this report we present aspects of the epidemiology of headache (i.e., pain in the head, face, ear, or neck) among children with brain tumors. The data are derived from the 3,291 subjects in the Childhood Brain Tumor Consortium databank. Overall, 62% of the children with brain tumors experienced chronic or frequent headaches prior to their first hospitalization: 58% of children with supratentorial tumors and 70% of children with infratentorial tumors. The relative frequency of headache increased through age 7 and then leveled off regardless of tumor location. For children under age 5, headache rarely had a duration of more than 1 year prior to hospitalization. Among children over age 4, headache duration of at least one year was significantly greater for supratentorial than for infratentorial tumors. Children with a brain tumor and headache had a different distribution of symptoms and neurologic signs than those without headache. Tumor location and headache status were interactively associated with the presence of other symptoms and neurologic signs. Children with headache had a greater number of other symptoms and neurologic signs. Regardless of tumor location among children with headache, nausea or vomiting, papilledema, and hypoactive tendon reflexes were more frequent, while upper extremity weakness, optic atrophy, and irritability were less frequent. Diplopia, coma, stiff neck, anesthesia or hypesthesia, pupillary abnormalities, and abnormalities of personality, academic performance, or speech were associated with headache in children with supratentorial tumors. No specific symptoms or neurologic signs were associated with headache in children with infratentorial tumors. Supratentorial craniopharyngioma, ependymoma, and protoplasmic astrocytoma were associated with significantly high rates of headache as was infratentorial pilocytic astrocytoma.

Adolescent↗
PubMed1976

Decreases of local brain temperature due to convection (local brain blood flow) and increases of local brain temperature due to activity.

The influence of local brain blood flow upon variations of local brain temperature in chronical experiments was investigated in cats. It was found that changes of local brain temperature in chronic experiments are esclusively due to changes of local metabolic heat production as long as the temperature of brain inflowing blood remains constant. Decreases of temperature due to convection (increase of local blood flow) are smaller than increases of temperature due to activity.

Animals↗
PubMed1989

Brain histology, blood-brain barrier and brain water after normothermic and hypothermic cardiopulmonary bypass in pigs.

The effect of hypothermia during cardiopulmonary bypass (CPB) on cerebral histopathology, blood-brain barrier permeability to serum proteins and water content was evaluated. Pigs were subjected to non-pulsatile CPB for 2 h at either normothermia or hypothermia, and a group of anaesthetised pigs served as normothermic controls. The histopathology was assessed on paraffin embedded sections. The permeability of the cerebral vessels was studied by immunocytochemical demonstration of extravasated serum proteins. The cerebral water content was assessed by specific gravity measurements. The histological studies demonstrated hydropic degeneration of the brain parenchyma and perivascular swelling of the astrocytic endfeet throughout both white and gray matter in the normothermic CPB group. Similar changes were not encountered during hypothermic CPB, which suggests a beneficial effect of decreased temperatures on brain tissue during CPB. Neither normothermic nor hypothermic CPB induced significant changes in the cerebrovascular permeability or in the specific gravities.

Animals↗
PubMed2002

Cross-linked polyhemoglobin-superoxide dismutase-catalase supplies oxygen without causing blood-brain barrier disruption or brain edema in a rat model of transient global brain ischemia-reperfusion.

In strokes, myocardial infarctions, severe sustained hemorrhagic shock, and donor organs, inadequate blood supply results in lack of oxygen to the tissue (ischemia). If ischemia is sustained, reperfusion with the needed oxygen can result in tissue injury (ischemia-reperfusion injury) due to formation of reactive oxygen species. We are studying an oxygen-carrying solution with anitoxidant activity formed by cross-linking hemoglobin, superoxide dismutase, and catalase to form PolyHb-SOD-CAT. The present report studies its effect on the blood-brain barrier and cerebral edema when used in a transient global brain ischemia-reperfusion rat model. We compare this solution to sham-control, oxygenated saline, stroma-free hemoglobin (SF-Hb), polymerized hemoglobin (PolyHb), and a mixture of SF-Hb, SOD, and CAT in free solution. The results show that the cross-linked PolyHb-SOD-CAT solution, unlike the other solutions, can supply oxygen to ischemic tissues without causing reperfusion injury in the transient global brain ischemia-reperfusion model.

Animals↗
PubMed2006

Delivery of chemotherapy and antibodies across the blood-brain barrier and the role of chemoprotection, in primary and metastatic brain tumors: report of the Eleventh Annual Blood-Brain Barrier Consortium meeting.

Although knowledge of molecular biology and cellular physiology has advanced at a rapid pace, much remains to be learned about delivering chemotherapy and antibodies across the blood-brain barrier (BBB) for the diagnosis and treatment of central nervous system (CNS) disease. A meeting, partially funded by an NIH R13 grant, was convened to discuss the state of the science, current knowledge gaps, and future directions in the delivery of drugs and proteins to the CNS, for the treatment of primary and metastatic brain tumors. Meeting topics included CNS metastases and the BBB, and chemoprotection and chemoenhancement in CNS disorders. The discussions regarding CNS metastases generated possibilities of chemoprotection as a means not only to decrease treatment-related toxicity but also to increase chemotherapy dose intensity. The increasing incidence of sanctuary brain metastasis from breast cancer, in part due to the difficulty of monoclonal antibodies (mAbs) such as herceptin to cross the BBB, was one of the most salient "take home" messages of the meeting.

Animals↗
PubMed1988

Brain natriuretic peptide-32: N-terminal six amino acid extended form of brain natriuretic peptide identified in porcine brain.

Brain natriuretic peptide (BNP) is a newly identified peptide of 26 residues, which has a remarkable homology to but is distinct from atrial natriuretic peptide. The peptide exerts natriuretic-diuretic activity as well as potent chick rectum relaxant activity. By using radioimmunoassay specific to BNP and immunoaffinity chromatography, we have isolated from porcine brain a novel peptide of 32 residues carrying a BNP structure at the C-terminus. The amino acid sequence of this peptide was determined to be: Ser-Pro-Lys-Thr-Met- Arg-Asp-Ser-Gly-Cys-Phe-Gly-Arg-Arg-Leu-Asp-Arg-Ile-Gly-Ser-Leu-Ser-Gly- Leu- Gly-Cys-Asn-Val-Leu-Arg-Arg-Tyr. This peptide is an N-terminal six amino acid extended form of BNP and henceforth is designated BNP-32. BNP and BNP-32 are found to be major forms of BNP family in porcine brain.

Amino Acid Sequence↗
PubMed1992

Effects of selected vasoactive substances on adenylate cyclase activity in brain, isolated brain microvessels, and primary cultures of brain microvessel endothelial cells.

The specific activity of adenylate cyclase was assayed in homogenates of gray matter, freshly isolated and primary cultured microvessel endothelial cells from bovine cerebral cortex. Specific activities for the tissues were 14.6 +/- 2.1, 15.6 +/- 2.7, and 8.4 +/- 1.5 pmol cAMP/mg protein/min +/- SD for gray matter, cultured microvessels, and freshly isolated microvessels, respectively. Adenylate cyclase associated with gray matter and cultured microvessels was sensitive to histamine and selected catecholamines. Perhaps due to metabolic deficiencies, adenylate cyclase of freshly isolated microvessels exhibited little or no response to either the catecholamines or histamine. Angiotensin II stimulated adenylate cyclase of both freshly isolated and cultured microvessels but had no effect on gray matter. Bradykinin did not stimulate cAMP generation in any of the tissues. Overall results support the role of cAMP in regulating brain microvessel functions and suggest that primary cultures of brain microvessels may be useful in examining cAMP-mediated biochemical pathways at the blood-brain barrier.

Adenylyl Cyclases↗
PubMed2002

A novel human gene whose product shares homology with bovine brain-specific protein p25 is expressed in fetal brain but not in adult brain.

We have cloned a novel human gene ( C14orf5) from a fetal brain cDNA library that is located on chromosome 14 and consists of 4 exons. It encodes a protein of 170 amino acids that shares homology with human p25 alpha and bovine p25. Reverse transcription-polymerase chain reaction analysis indicated that it is highly expressed in liver and pancreas. Its transcripts could not be detected in adult brain but could be found in fetal brain.

Amino Acid Sequence↗
PubMed1981

[Inflammatory brain oedema and regional brain metabolism in experimental brain abscess in cats (author's transl)].

Brain abscess were produced in cats, by inoculating an agar-bouillon mixture with Staphylococcus aureus into the white matter of the right cerebral hemisphere. The accompanying oedema, which can be regarded as vasogenic, extended outwards from the site of inflammation and by the seventh day had involved the entire right hemisphere. As the abscess became encapsulated the oedema at the periphery subsided but it persisted, however, in the close proximity of the causative organisms to the tissue. The changes in the regional brain metabolism were most obvious at the time when the oedema was maximal. This tended to become normal with the increasing encapsulating which took place from the seventh day onwards.

Animals↗
PubMed2004

The "Yoking" of glutamatergic brain mechanisms involved in controlling brain neuronal excitability and psychosis to brain mechanisms involved in appetite regulation: a new hypothesis on the origin of psychosis.

The authors speculate that the human primate evolved psychosis generating brain mechanisms in the service of certain feeding behaviors (i.e., appetite, foraging) during the course of evolution. Furthermore, these "psychosis generating brain mechanisms" may have grown directly out of brain mechanisms servicing appetite, of which neuropeptide Y (NPY) played an important role. A case is made for an NPY contribution to the pathophysiology of psychosis. We hypothesize that the psychomimetic effects of NPY extend to supporting certain "psychomotor" functions that might have been useful for obtaining food resources in "stressful environments" (potentially food resource rich/predator-competitor dangerous). The "psychomotor" functions proposed include helping the evolving ancestral human primate overcome behavioral inhibitions and fears related to venturing into "stressful environments" (potentially food resource rich/predator-competitor dangerous) after their home ranges had been stripped of resources, by providing feelings of decreased anxiety (anxiolysis), infatigability, and, perhaps, even grandiose delusions of physical ability and supernatural supports. We further speculate that it is this NPY mechanism that in part becomes dysregulated in idiopathic psychotic disorders such as schizophrenia. The NPY connection with psychosis could theoretically account for the possible associations between weight changes and antipsychotic response (e.g. [Acta Psychiatr. Scand. 100 (1999) 3] reported by others and body mass index and cocaine-induced psychosis by our group (i.e. [Israel J. Psychiatr. (2004), in submission]).

Affective Disorders, Psychotic↗
PubMed1991

Blood-brain barrier: transport studies in isolated brain capillaries and in cultured brain endothelial cells.

The development of in vitro BBB models consisting of isolated brain capillaries and cultured brain microvessel endothelial cells has made possible the study of BBB transport phenomena at the cellular level. Basic characteristics of BBB transport of endogenous and exogenous solutes and their biochemical, pharmacological, ontogenic, and pathological regulation mechanisms have been investigated. This information has led not only to a better understanding of BBB transport but also to the construction of strategies for improving drug delivery to the CNS for diagnosis and therapeutics. To elucidate the complexity of BBB transport, in vivo studies are always necessary at some point; however, in vitro systems can be useful complements to the in vivo systems. The tissue culture systems seem to be especially important in the clarification of cellular, biochemical and molecular features of BBB transport. Appropriate systems should be selected or combined, depending on the purpose of the investigation.

Animals↗
PubMed1991

Molecular species of phosphatidylcholine containing very long chain fatty acids in human brain: enrichment in X-linked adrenoleukodystrophy brain and diseases of peroxisome biogenesis brain.

Molecular species of phosphatidylcholine containing unsaturated (i.e., monoenoic and polyenoic) 32- to 40-carbon (very long chain) fatty acids (VLCFA-PC) are present in normal human brain, the fatty acid composition changing significantly with development. There is a marked increase in the concentration and a change in the polyenoic VLCFA composition of these molecular species in brains of patients with inherited defects in peroxisomal biogenesis [Zellweger's syndrome, neonatal adrenoleukodystrophy (ALD), and infantile Refsum's disease]. In contrast, there is a marked increase in monoenoic VLCFA-PC in X-linked ALD whereas molecular species containing polyenoic VLCFA are minor components.

Adolescent↗
PubMed1983

Pathophysiological aspects of blood-brain barrier disturbances in experimental brain tumors and brain abscesses.

Experimental tumors and abscesses were produced by intrahemispheric inoculation of a blastomatous glial cell clone and of staphylococcus aureus, respectively. In both models severe vasogenic brain edema developed. The site of the barrier lesion was identified by systemic application of Evans blue or peroxidase, and the spread of edema by immunoautoradiographic localisation of extravasated serum proteins. In both experimental conditions, serum proteins accumulated diffusely in the white matter of the ipsilateral hemisphere, although the barrier lesion was strictly confined to the pathological focus. Water content of the edematous white matter in the vicinity of tumors and abscesses increased from 69.1 to 80.6 and 82.3 ml/100g w.w., respectively. This increase was associated with a volume-dependent decrease of flow, a parallel increase of sodium and an increase of extravasated serum proteins. The latter was determined by a newly developed immunochemical approach with appropriate corrections for the intravascular fraction of total serum protein content. The calculated concentration of sodium in edema fluid of tumors and abscesses amounted to 132 and 129 ueq/ml, respectively. The concentration of serum proteins was 8.7 and 6.4 mg/ml, respectively. Protein content of edema fluid, in consequence was less than 10% of blood serum. This suggests that fluid accumulation in vasogenic edema cannot be explained by the oncotic properties of extravasated proteins alone.

Animals↗
PubMed2006

Effectiveness of stereotactic radiosurgery alone or in combination with whole brain radiotherapy compared to conventional surgery and/or whole brain radiotherapy for the treatment of one or more brain metastases: a systematic review and meta-analysis.

PURPOSE: To assess the effectiveness of SRS alone or in combination with WBRT compared to surgery and/or WBRT in prolonging survival and improving the quality-of-life and functional status of patients with brain metastases. METHODS AND MATERIALS: A meta-analysis of randomized controlled trials and concurrent cohort studies examining SRS versus SRS + WBRT, SRS versus WBRT +/- surgical resection, SRS versus surgical resection only, or SRS + WBRT versus WBRT was conducted. Trial registers, bibliographic databases, and reference lists from selected studies and recent issues of relevant journals were searched. Neuro-oncology specialists were also contacted. All studies were analyzed independently by two reviewers, applying validated critical appraisal techniques. RESULTS: The review identified three RCTs and one cohort study. Among patients with multiple metastases, no difference in survival between those treated with WBRT + SRS and those treated with WBRT was found. However, in patients with one metastasis, a statistically significant difference, favoring those treated with WBRT + SRS, was observed. Regarding local tumor control at 24 months, rates were significantly higher in the WBRT + SRS treatment arm, regardless of the number of metastases. CONCLUSIONS: Adding SRS to WBRT improves survival in patients with one brain metastasis. Combining SRS and WBRT improves local tumour control and functional independence in all patients.

Brain Neoplasms↗
PubMed1992

Brain states--brain rhythms--brain responses.

Oscillation and resonance of electrical activity of certain sets of neurons in the brain and spinal cord is an important factor in the organization of those properties of connectivity that must be tuned by function. Once connectivity has reached some degree of specificity important biological and chemical events must occur to stabilize synaptic inputs and localize excitable sites to particular areas of the cell surface. It has been proposed that intrinsic electroresponsiveness generates internal computational states that serves as a reference frame or context for incoming information. The intrinsic activity is proposed to be a part of the vectorial coordinate space that sensory and motor transformations occur in context of a particular functional state such as attention and expectation that can modify the relevance of a given sensory input. The most significant mechanism in generation of oscillation properties of the brain are the intrinsic properties of individual neurons. This concept presents a shift of emphasis from properties of circuits to properties of single neurons. Feedback circuits and synchronization of single oscillators into sets of coupled oscillators which in turn generates field potentials such as (EEG) and evoked response (ER).

Animals↗
PubMedDate not supplied

[The blood-brain barrier. II. Pathology: brain tumors, brain edema, hypertension, epilepsy].

In the first part of the publication the authors presented the blood-brain (BBB) under physiological conditions. The second part includes the current opinions concerning BBB during various disorders of the central nervous system (CNS) and hypertension. The imbalance of BBB is often not only a consequence of a pathologic status, but can be also cause of it. On the other hand BBB influences the therapy of many illnesses by restricting the penetration of drugs to the CNS.

Adrenal Cortex Hormones↗
PubMed2003

Music and the brain. Lessons from brain diseases and some reflections on the "emotional" brain.

Studies are reviewed from the perspective of a neurologist and epileptologist interested in "music and the brain." At the neurocognitive level, deficits in pitch discrimination of patients with brain lesions and those during the intracarotid amobarbital test are outlined, because they show that the temporal lobe and, in particular, the right acoustic cortex are crucial. Hallucinations of music during epileptic seizures as well as the analysis of musicogenic epilepsy point to the same gross localization and lateralization. At the esthetic level, music theoretical concepts on the consonance-dissonance dichotomy and related EEG examinations are reported, which illustrate the importance of mesiolimbic temporal lobe structures for the pleasure that we might experience when listening to music. The complex interaction of many neuronal circuits and assemblies of both hemispheres in musical perception and performance is illustrated by musical analysis of a recording by an organ player who experienced a right temporal lobe seizure. This analysis revealed that the seizure-induced errors of the left hand were compensated with the right hand in a musically meaningful way.

Emotions↗