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PubMed2002

The administration of pig brain phospholipids versus soybean phospholipids in the diet during the period of brain development in the rat results in greater increments of brain docosahexaenoic acid.

Dietary porcine brain phospholipids are much more efficient than soybean phospholipids for ensuring a normal (optimal obtained with lab chow diet) level of docosahexaenoic acid (DHA) in tissues and brain subcellular fractions (brain myelin and nerve endings). Two weeks before mating, rats were divided into two groups (one group was subdivided into subgroups, fed with varying amounts of porcine brain phospholipids; the other group was divided into subgroups fed varying amounts of soybean phospholipids). Pups were killed when 21 days old. DHA (22:6(n-3)) increased up to normal levels in parallel with increasing amounts of (n-3) fatty acids (omega-3 fatty acids) in the diet, up to 60 mg with dietary porcine brain phospholipids and up to 200 mg with soybean phospholipids. Thus a smaller amount of dietary brain phospholipids resulted in the same level of DHA in tissues as a larger amount of dietary soybean phospholipids. In contrast, 22:5(n-6) declined when (n-3) fatty acids in the diet increased. It stabilized at 60 mg of (n-3) fatty acids/100 g diet with brain phospholipids, and approximately 200 mg/100 g diet with soybean phospholipids. As 22:5(n-6) replaced DHA in tissue when (n-3) fatty acids were not sufficient in the diet, this result shows that the recovery of a normal (and minimal) amount of 22:5(n-6) was obtained with lower dietary levels of brain phospholipids compared with soybean phospholipids.

Animals↗
PubMed1995

Testis-brain RNA-binding protein, a testicular translational regulatory RNA-binding protein, is present in the brain and binds to the 3' untranslated regions of transported brain mRNAs.

Previous studies have demonstrated that a phosphoprotein in testis binds to transcript c, a sequence containing two highly conserved elements, Y and H, in the 3' untranslated region (UTR) of mouse protamine 2 mRNA (mP2) and represses its translation in vitro. When gel-retardation assays were performed with cytoplasmic extracts prepared from seven different mouse tissues, we found that brain in addition to testis contains a protein that binds to transcript c. Both the testis and brain proteins are found exclusively in the nonpolysomal fractions of their postmitochondrial extracts. The testis and brain proteins appear to be identical according to numerous criteria: the complexes they form with transcript c have identical mobility in native gels, identical optimal pH, identical lability to increased salt concentrations, identical chromatographic properties, identical molecular sizes as judged from UV crosslinking, and identical peptide mapping as revealed by V8 digestion of the UV crosslinked protein-RNA complexes. In addition to binding to the same conserved sequence in the 3'UTR of mP2, the phosphoprotein from testis and brain, hereafter called testis-brain RNA-binding protein (TB-RBP), also specifically binds to a similar sequence in the 3'UTR of brain Tau mRNA. Since TB-RBP binds to the 3'UTRs of several translationally regulated mRNAs in testis and since numerous transported brain mRNAs also contain the same conserved binding elements, we propose that TB-RBP plays a role in mRNA storage, translocation, and/or localization in brain and testis.

Ammonium Sulfate↗
PubMed1987

African trypanosomiasis: haematogenic brain parasitism early in experimental infection through bypassing the blood-brain barrier, with considerations on brain trypanosomiasis in man.

A hematogenic invasion of the brain in suckling NMRI mice infected with Trypanosoma brucei rhodesiense was initiated by means of a mechanical damage of the blood-brain barrier. The brain was punctured after development of a blood infection. Brain infection was found in 31 out of 32 animals examined. Trypanosomes are initially capable of rapid multiplication. The number of parasites was highest during the 1st week. From the middle of the 2nd week the number of parasites decreased continuously, alongside increasing atrophy. In the 3rd and 4th week only rare degenerating or ghost trypanosomes were present. No reactions were detected in the glial and mesenchymal cells. It is presumed that the short phase of trypanosome multiplication is due to the temporary collateral oedema of the brain tissue. The decrease in parasites from the 2nd week onwards is mainly attributed to natural death due to particular anatomical features of the brain tissue. These are also responsible for the absence of defensive inflammatory reactions, based on the hypothesis that contact between trypanosomes and the cells of the brain blood vessels is prevented.

Animals↗
PubMed1998

Combined use of carboxyl-directed protein pegylation and vector-mediated blood-brain barrier drug delivery system optimizes brain uptake of brain-derived neurotrophic factor following intravenous administration.

PURPOSE: Peptide drug delivery to the brain requires optimization of (a) plasma pharmacokinetics and (b) blood-brain barrier (BBB) permeability. In the present studies, plasma pharmacokinetics are improved with protein pegylation and BBB transport is facilitated with the use of vector-mediated drug delivery using the OX26 monoclonal antibody (MAb) to the rat transferrin receptor, which undergoes receptormediated transcytosis through the BBB in vivo. METHODS: A conjugate of OX26 and streptavidin (SA), designated OX26/SA, was prepared in parallel with the carboxyl-directed pegylation of brain-derived neurotrophic factor (BDNF). A novel bifunctional polyethyleneglycol (PEG) was used in which a hydrazide (Hz) was attached at one end and a biotin moiety was attached to the other end. This allowed for conjugation of BDNF-PEG-biotin to OX26/SA. RESULTS: The brain uptake of BDNF-PEG-biotin was increased following conjugation to OX26/SA to a level of 0.144 +/- 0.004% injected dose per g brain and a BBB permeability-surface area product of 2.0 +/- 0.2 microL/min/g. CONCLUSIONS: These studies demonstrate that peptide drug delivery to the brain can be achieved with advanced formulation of protein-based therapeutics. The formulation is intended to (a) minimize rapid systemic clearance of the peptide, and (b) allow for vector-mediated drug delivery through the BBB in vivo. Following this dual formulation, the brain uptake of a neurotrophin such as BDNF achieves a value that is approximately 2-fold greater than that of morphine, a neuroactive small molecule.

Animals↗
PubMed1980

The significance of the amount of fluid surrounding the brain to the recognition of brain swelling (or atrophy) at autopsy: a new and routinely applicable method of diagnosing abnormal brain size.

A new method of measuring relative brain size (relative to the skull cavity) at autopsy is presented. It is convenient and accurate and may be applied almost routinely. It consists of measuring the volume of the brain and the fluids surrounding it. These two volumes together must equal the intracranial volume. An abbreviated method consists of relating the fluid volume to the brain weight. This abbreviated method should not be routinely relied on when the brain size deviates slightly from normal. A review of the pertinent literature shows that other existing methods of determining relative brain size are impractical. The significance of measuring peri-brain fluids at the time of brain removal has not been appreciated prior to this report.

Atrophy↗
PubMed2006

The mind-brain relation and neuroscientific foundations: III. Brain and psychopathology, the split brain, and dreaming.

In addition to the findings of neuroscientific research on brain function, reviewed in the previous articles (Meissner, 2006a, 2006b), contemporary findings relevant to the mind-brain relation derive also from the study of the underlying patterns of brain dysfunction related to various forms of psychopathology. Other information derives from study of split-brain conditions and from research on dream processes and their relation to brain mechanisms. Review of these research findings casts further light on aspects of the mind-brain relation and further substantiates a unified theory of mind-brain integration.

Brain↗
PubMed2000

Role of nitric oxide in blood-brain barrier permeability, brain edema and cell damage following hyperthermic brain injury. An experimental study using EGB-761 and Gingkolide B pretreatment in the rat.

The role of oxidative stress in hyperthermia induced upregulation of constitutive and inducible isoforms of nitric oxide synthase (NOS) in the central nervous system (CNS) was investigated using immunohistochemistry in a rat model. Exposure of rats to heat stress at 38 degrees C for 4 h resulted in marked upregulation of constitutive NOS (cNOS) and a mild but significant expression of inducible NOS (iNOS) in several brain regions exhibiting leakage of the blood-brain barrier (BBB), brain edema formation and cell injury. Pretreatment with the potent antioxidative compound EGB-761 or its constituent, Ginkgolide B significantly attenuated upregulation of cNOS and iNOS in the brain and also reduced the BBB permeability disturbances, brain edema and cell injury. These neuroprotective effects were most marked in the EGB-761 pretreated rats. Our observations strongly suggest that (i) EGB-761 and Ginkgolide B pretreatment offer significant neuroprotection in hyperthermic brain injury, (ii) upregulation of cNOS and iNOS are injurious to the cell and, (iii) oxidative stress plays an important role in NOS expression and cell injury.

Animals↗
PubMed2006

Measuring brain uptake and incorporation into brain phosphatidylinositol of plasma myo-[2H6]inositol in unanesthetized rats: an approach to estimate in vivo brain phosphatidylinositol turnover.

The in vivo rate of turnover of phosphatidylinositol (PtdIns) in brain is not known. In brain, certain receptor-mediated signal transduction involves metabolism of PtdIns and a method to measure its turnover in awake animals is useful in studying the effect of lithium and other therapeutic agents. In a method described here, rats were infused subcutaneously with myo-[2H6]inositol (Ins*) using an osmotic pump and, at 1 and 8 weeks, concentrations of free myo-inositol (Ins) and Ins* in plasma and brain were measured by GC-MS (chemical ionization). Also, PtdIns and PtdIns* together in brain were isolated, and Ins and Ins* from their headgroups were released enzymatically and specific activity of incorporated inositol was measured. The specific activity of inositol reached a steady state in plasma within 1 week of infusion, but not in brain even at 8 weeks. However, in brain, the specific activity of phosphatidylinositol was same as that of inositol at both time-points, suggestive of fast turnover of PtdIns. The animal experiment and the analytical methodology described here should be useful for measuring the rate of turnover of brain PtdIns in pathological and drug treatment conditions.

Animals↗
PubMed1994

[Analysis of computed X-ray tomography of the brain in incontinence patients with senile dementia. Relationship between circulatory defect of the brain, brain atrophy and urinary incontinence].

To evaluate the condition of incontinence in patients with senile dementia, we performed computed tomography X-rays to the brain and analyzed the relationship among the circulatory defect of the brain, the brain atrophy and the degree of incontinence. There were 92 patients subjected to this study who were hospitalised due to senile dementia; 74 patients had vascular dementia, 10 patients had senile dementia of Alzheimer type, and 8 patients had the mixed type. (age ranged: 54-95 years; mean: 80.3 years). The degree of incontinence in these patients varied as follows: 18 patients with continence, 16 patients with moderate incontinence, 58 patients with total incontinence. The diagnosis of circulatory defect of the brain was based on computed tomography observation of periventricular lucency (P.V.L.), and the degree of brain atrophy was evaluated based on 4 criteria: the Lateral body ratio, the Huckman number, the Evans ratio, and the enlargement of the subarachnoid space. Among the 92 patients, P.V.L. was present in 31 patients, among them 27 patients suffered from incontinence. There was a significant correlation between P.V.L. and incontinence (p < 0.001). As the incontinence progressively worsened (Continence, Moderate incontinence Total incontinence), the lateral body ratio increased to 24.8, 27.8, 28.6, (p < 0.05). The Huckman number also increased to 18.3, 19.3, 21.3, (p < 0.01), and the evans ratio likewise 29.9, 32.3, 33.7 (p < 0.01). The enlargement of the subarachnoid space was also correlated with the severity of incontinence. We conclude that urinary incontinence originating from senile dementia is connected to brain atrophy and is strongly influenced by the circulatory disorders of the brain.

Aged↗
PubMed1975

[Comparative quantitative study on brains of wild and laboratory rats. I. Comparison of volume of total brain and classical brain parts].

The intraspecific allometric relation between brain weight and body weight of wild Norway rats and laboratory rats was gained from sufficient material. The intraspecific allometry exponent a=0.25, being typical for mammals, also came out as a result for Norway and laboratory rats. But laboratory rats have 8.3% less brain substance at a comparable body weight. This decrease in brain size was interpreted as an adaption to the specific conditions of domestication and discussed accordingly. Futhermore the fresh volumes of the fundamental brain parts telencephalon, diencephalon, mesencephalon, cerebellum, medulla oblongata, neocortex, corpus striatum and allocortex were ascertained by means of serial sections of 8 Norway and 8 laboratory rats, and they were compared with each other by their average brain proporationing. Consequently, differently strong reduction intensities in the sizes of these brain parts from 1.6% (medulla oblongata) to 12.5% (neocortex) became evident. The high reduction values of corpus striatum (10.9%) and cerebellum (10.3%) were especially remarkable. They almost reached the same degree as the forebrain (10.6%). The size reduction of the measured brain parts of rats, caused by domestication were compared with the results of other domestic mammals and discussed accordingly.

Animals↗
PubMed1990

Effect of dietary tryptophan on plasma and brain tryptophan, brain serotonin, and brain 5-hydroxyindoleacetic acid in rainbow trout.

In order to determine the effect of dietary tryptophan level on plasma and brain tryptophan, brain serotonin, and brain 5-hydroxyindoleacetic acid levels, juvenile rainbow trout (Salmo gairdneri) were raised for 16 weeks on semipurified diets containing 0.06%, 0.16%, 0.21%, 0.26%, 0.39%, or 0.59% tryptophan. After 14 weeks, feed intake was depressed in fish fed the diets containing 0.06% or 0.16% tryptophan. No further differences in feed intake were noted between the remaining treatments. In addition, body weight was lower in fish fed diets containing 0.06%, 0.16%, or 0.21% tryptophan compared with fish fed higher levels. After 16 weeks of feeding the test diets, plasma tryptophan levels were found to be directly related to dietary tryptophan levels. Similarly, increased dietary levels of tryptophan resulted in increased brain levels of tryptophan, serotonin, and 5-hydroxyindoleacetic acid. These results demonstrate that in rainbow trout, as in mammals, altered dietary levels of tryptophan result in alterations in plasma and brain tryptophan, brain serotonin, and brain 5-hydroxyindoleacetic acid.

Journal Article↗
PubMedDate not supplied

Reduced myelinogenesis and recovery in hyperphenylalaninemic rats. Correlation between brain phenylalanine levels, characteristic brain enzymes for myelination, and brain development.

In a previous paper (Burri et al., 1990), we have shown that experimental hyperphenylalaninemia (hyper-Phe) in 3-17 d-old rats leads to reduced myelinogenesis. Such treated rats recover during a 6 w low phenylalanine (Phe) period between days 17 and 59. In order to get more detailed information about the disturbed myelinogenesis and recovery, we measured in hyper-Phe rats the developmental pattern of two brain enzymes typical for myelination, cerebroside sulfotransferase (CST), and 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNP), and other developmental parameters. Further, we correlated brain Phe levels with the brain damage in hyper-Phe rats, and we measured brain acetylcholinesterase (AChE) as a neuronal marker. Experimental hyper-Phe rats, injected between postnatal days 3 and 17 with alpha-methylphenylalanine and phenylalanine, showed a delayed age-dependent increase of CST activity, compared to that of controls. In hyper-Phe rats, CST peak activity was reached 2-4 d later, and was lower than in controls. The age-dependent decrease of the CST activity, however, started in test and control rats at the same time, at day 21. Between days 24 and 59, hyper-Phe rats had normal CST activity. CNP activity in hyper-Phe rats was lower than in controls from day 10 to 35, and recovered to normal values between days 35 and 59. Our results indicate that recovery from reduced myelinogenesis is possible after the period of fast myelination without compensatory increased CST activity. Further, the brain damage in test rats with Phe levels higher than average is more severe than in test rats with Phe levels lower than average; and there is no effect of hyperphenylalaninemia on brain neurons containing AChE.

Acetylcholinesterase↗
PubMed1998

Inhibition of P-glycoprotein: rapid assessment of its implication in blood-brain barrier integrity and drug transport to the brain by an in vitro model of the blood-brain barrier.

PURPOSE: The objective of this work was to assess, in vitro, the passage of P-glycoprotein dependent drugs across brain capillary endothelial cells, when these drugs are associated with a reversing agent. METHODS: An in vitro model of the blood-brain barrier consisting of a coculture of brain capillary endothelial cells and astrocytes was used. RESULTS: We demonstrate that P-glycoprotein expression is upregulated by the presence of astrocytes. Uptake in the cells and transport across endothelial cell monolayers of vincristine, cyclosporin A and doxorubicin were studied. Using S9788 or verapamil as reversing agents, we found an increase in vincristine transport across the endothelial cell monolayers. On the other hand, the association of S9788 or verapamil with cyclosporin A failed to increase the transport of this drug. An increase in the transport of doxorubicin from luminal to abluminal compartment was also observed, due to endothelial cell monolayer breakdown. CONCLUSIONS: Using this model, it is possible to predict the passage of a P-glycoprotein dependent drug to the brain or its sequestration in brain capillary endothelial cells when this drug is associated with a reversing agent, or its toxicity on the blood-brain barrier integrity.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

Coping with illness after brain diseases--a comparison between patients with malignant brain tumors, stroke, Parkinson's disease and traumatic brain injury.

PURPOSE: This study investigates coping styles in patients suffering from different brain disorders (malignant brain tumors, stroke, Parkinson's disease and traumatic brain injury). METHOD: In a combined analysis of four prospective studies we investigated 21 patients with malignant glioma at the end radiochemotherapy, 30 patients one year after ischemic stroke, 54 patients suffering from various stages of Parkinson's disease, and 58 patients 6 to 8.5 months after traumatic brain injury. The assessment of coping with illness was based on the Freiburg Questionnaire on Coping with illness. RESULTS: With few exceptions, coping styles did not differ across the various brain pathologies. Differences occurred with respect to 'active, problem-oriented coping' (decreased in stroke patients), and coping by search for religious relief or quest for sense (increased in patients with Parkinson's disease). CONCLUSION: Differences in coping styles could be mainly related to age and social factors. Individual coping strategies seem only to be little related to the type of brain pathology.

Acute Disease↗
PubMed1979

Acute intracranial hypertension and auditory brain-stem responses. Part 2: The effects of brain-stem movement on the auditory brain-stem responses due to transtentorial herniation.

Movement of the upper brain stem (inferior colliculus) was correlated with the alterations in the amplitude of wave V of the auditory brain-stem responses (BER's) during supratentorial brain compression in cats. In vivo observation of the brain stem and postmortem inspection show that suppression of the amplitude of BER wave V reflects the extent of caudal displacement of the inferior colliculus. Marked suppression of the amplitude of BER wave V (approximately 30% of control) correlates with the beginning of transtentorial herniation, and complete suppression of the wave V indicates complete transtentorial herniation of the brain-stem and supratentorial structures. The BER wave V is thought to be a sensitive index of caudal movement of the upper brain stem due to transtentorial herniation.

Animals↗
PubMed1998

[Immunohistochemical research on brain stem injury: expression of heat shock protein 70 in rat brain after traumatic brain stem injury].

The aim of this study was to determine the expression of heat shock protein 70 (HSP70) as molecular chaperones, following traumatic brain stem injury(TBSI). The expression of HSP70 was detected in respective brain regions of rats 1 h, 3 h, 6 h, 12 h, 24 h after brain stem stabbing wound. Numerous HSP70 immunoreactivity positive blood vessel endothelioid and glia cells were found in cerebral, cerebellar cortex and hippocampus after 1 h, with H.E stain unchanged. In the area near the focal of brain stem injury, HSP70 immunoreactivity positive neurons increased significantly after 1 h of injury, reaching the highest level after 3 h, much higher than in other areas. HSP70 immunoreactivity positive cells still existed after 24 h of injury. It was suggested that TBSI cause the defectiveness of protein structure in brain, and induce HSP70 proteolysis of denature protein including misfolding or aggregate. TBSI can be diagnosed regionally by the increasing of HSP70 immunoreactivity positive neurons in the focal of brain stems.

Animals↗
PubMed2005

Surgical resection and whole brain radiation therapy versus whole brain radiation therapy alone for single brain metastases.

BACKGROUND: The treatment of brain metastasis is generally palliative, with whole brain radiation therapy (WBRT), since the majority have uncontrollable systemic cancer. In certain circumstances, such as single brain metastases, death may be more likely from brain involvement than systemic disease. In this group, surgical resection has been proposed to relieve symptoms and prolong survival. OBJECTIVES: To assess the clinical effectiveness of surgical resection plus WBRT versus WBRT alone in the treatment of single brain metastasis. SEARCH STRATEGY: The Cochrane Cancer Network Specialised trials register (July 2003), Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 1 2003), MEDLINE (1966 to July 2003), EMBASE (1980 to July 2003), CANCERLIT (1980 to July 2003), BIOSIS (1985 to July 2003) and SCIENCE CITATION INDEX (1981 to July 2003) were searched. References of identified studies were hand searched, as was the Journal of Neuro-Oncology over the previous 10 years and Neuro-Oncology over the past 2 years, including all conference abstracts. Specialists in neuro-oncology were also contacted. SELECTION CRITERIA: Randomized controlled trials (RCTs) comparing surgery and WBRT with WBRT alone, in patients with single brain metastasis. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality and extracted data. MAIN RESULTS: Three RCTs were identified, with 195 patients in total. No significant difference in survival was noted hazard ratio (HR) 0.74 (95% confidence interval (CI) 0.39 to 1.40, p = 0.35), although there was a high degree of heterogeneity between trials. One trial has shown surgery and WBRT to increase the duration of functionally independent survival (FIS) HR 0.42 (95% CI 0.22 to 0.80, p < 0.008). There is a trend for surgery and WBRT to reduce the number of deaths due to neurological cause odds ratio (OR) 0.57 (95% CI 0.29 to 1.10, p = 0.09). Adverse effects were not found to be statistically more common in any group. AUTHORS' CONCLUSIONS: Surgery and WBRT may improve FIS but not overall survival. There is a trend that it may reduce the proportion of deaths due to neurological cause. All these results were in a highly selected group of patients. Operating on metastases does not confer significantly more adverse effects.

Brain Neoplasms↗
PubMed2001

Fluctuations in brain glucose concentration during behavioral testing: dissociations between brain areas and between brain and blood.

Traditional beliefs about two aspects of glucose regulation in the brain have been challenged by recent findings. First, the absolute level of glucose in the brain's extracellular fluid appears to be lower than previously thought. Second, the level of glucose in brain extracellular fluid is less stable than previously believed. In vivo brain microdialysis was used, according to the method of zero net flux, to determine the basal concentration of glucose in the extracellular fluid of the striatum in awake, freely moving rats for comparison with recent hippocampal measurements. In addition, extracellular glucose levels in both the hippocampus and the striatum were measured before, during, and after behavioral testing in a hippocampus-dependent spontaneous alternation task. In the striatum, the resting extracellular glucose level was 0.71 mM, approximately 70% of the concentration measured previously in the hippocampus. Consistent with past findings, the hippocampal extracellular glucose level decreased by up to 30 +/- 4% during testing; no decrease, and in fact a small increase (9 +/- 3%), was seen in the striatum. Blood glucose measurements obtained during the same testing procedure and following administration of systemic glucose at a dose known to enhance memory in this task revealed a dissociation in glucose level fluctuations between the blood and both striatal and hippocampal extracellular fluid. These findings suggest, first, that glucose is compartmentalized within the brain and, second, that one mechanism by which administration of glucose enhances memory performance is via provision of increased glucose supply from the blood specifically to those brain areas involved in mediating that performance.

Animals↗