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PubMed1977

White-gray matter differentiation in computed tomography.

A numerical analysis has been performed on six regions of interest within the brain for a total of 60 patients. Three areas of white matter and three of gray matter were included. A difference of 7.1 +/- 1.3 Hounsfeld units (HU: 1,000 scale) was found between white and gray matter. For eight patients who were under 15 years of age, the difference was 5.1 +/- 0.6 HU. Contrast injection resulted in a general increase of values, with gray matter showing a greater elevation by 0.5 HU. The numerical evaluation of white and gray matter has proven to be useful in the diagnosis of leukoencephalopathy.

Adolescent↗
PubMed1991

Localization of the CD44 glycoprotein to fibrous astrocytes in normal white matter and to reactive astrocytes in active lesions in multiple sclerosis.

The CD44 antigen is a proteoglycan recently implicated in several adhesion events including that of lymphocytes to endothelium. The CD44 antigen, reactive with monoclonal antibody (MAb) 44D10, has been shown previously to be expressed in normal human white matter homogenates and to be found at higher concentrations in brain homogenates of victims of multiple sclerosis (MS). The cellular localization of CD44 in human brain of normal individuals and in those afflicted with MS has now been determined. Monoclonal antibody 44D10 reacted with astrocyte-like cells in 40 microns thick paraformaldehyde-fixed sections but not in thin (6 microns) fixed sections. A double labeling experiment performed on a frozen brain section with MAb 44D10 and rabbit anti-glial fibrillary acidic protein (GFAP), a cytoplasmic marker of astrocytes, confirmed the co-localization of these two antigens. The reactivity with brain tissue sections of a rabbit antiserum produced against lymphocyte-CD44 could be absorbed by a preparation of the CD44 glycoprotein, purified 2,100-fold from a white matter homogenate. The antiserum was shown by Western blot analysis to be specific for p80 glycoprotein in brain extracts derived from a normal and MS patients. This antibody reacted with fibrous astrocytes predominantly in white matter; staining was also noted in subependymal and subpial regions. Inhibition studies using a cellular radioimmunoassay indicated that the highest concentrations of CD44 in three MS victims were found in plaques, followed by periplaques and non-involved areas of white matter which were higher than normal white matter. Reactive astrocytes, identified in active lesions, expressed high levels of CD44 on their surfaces. Thus, CD44 is associated with astrocytes in human brain and the increased expression observed in MS brain may reflect activation and/or proliferation of astrocytes implicated in the pathogenesis of this disease.

Astrocytes↗
PubMed2001

Measurements of both hippocampal blood flow and hippocampal gray matter volume in the same individuals with Alzheimer's disease.

We evaluated both hippocampal blood flow and hippocampal gray matter volume using single photon emission tomography and magnetic resonance imaging in the same individuals with Alzheimer's disease (AD) and in age-matched controls. The hippocampal blood flow was not significantly lower in mild AD patients (n = 21, Mini-Mental State Examination (MMSE) 23.3+/-2.1) than in controls (n = 16) with a 57% overlap. The hippocampal blood flow was significantly lower in advanced AD patients (n = 22, MMSE 15.4+/-3.2) than in controls. The hippocampal gray matter volume was significantly smaller in mild AD patients than in controls, although a 43% overlap was present. There was no significant difference in the hippocampal gray matter volume between the mild and advanced AD patients. The combination of measurements of hippocampal blood flow and gray matter volume discriminated 71% of mild AD patients from controls. These results suggest the usefulness of a combined analysis of hippocampal blood flow and gray matter volume for the early diagnosis of AD.

Aged↗
PubMed2006

Neonatal nucleated red blood cells and the prediction of cerebral white matter injury in preterm infants.

OBJECTIVE: To estimate whether neonates with cerebral white matter injury have significant elevations in nucleated red blood cell counts and to estimate their predictive ability in identifying injury. METHODS: This case-control study identified 176 infants born at 23-34 weeks of gestation between November 1994 and October 2004 at a single university hospital and with cerebral white matter injury characterized by periventricular leukomalacia (PVL) or ventriculomegaly due to white matter atrophy. A control was matched to each case using the subsequent delivery within 7 days of that gestational age without brain injury. RESULTS: The gestational age at birth was 27 weeks for both groups, but the cases had a significantly lower birth weight (mean +/- standard deviation: 958 +/- 306 g compared with 1,038 +/- 381 g, P = .001). There was no difference in cesarean delivery (48% cases compared with 44% controls, P = .59). The cases had a significant increase in nucleated red blood cells per 100 white blood cells (WBC) (median, 5th percentile and 95th percentile: 22, 3 and 374 cases compared with 14, 1 and 312 controls; P = .02). Markers of chronic hypoxia, such as intrauterine growth restriction and oligohydramnios, and markers of acute hypoxia, such as an umbilical arterial pH less than 7.0 or base excess less than -12 mM, were both associated with significantly elevated neonatal nucleated red blood cell counts. A neonatal nucleated red blood cell count of 18 per 100 WBCs had a sensitivity of 56.9%, specificity of 57.9%, positive predictive value of 57.9%, and negative predictive value of 56.9% in predicting the development of cerebral white matter injury in this matched case-control sample. CONCLUSION: Preterm neonates with cerebral white matter injury have significant increases in nucleated red blood cell counts. Both acute and chronic hypoxia-ischemia can increase these counts, which limits their usefulness in timing injury. The predictive value of nucleated red blood cell counts at birth in identifying injury is poor. LEVEL OF EVIDENCE: II-2.

Biomarkers↗
PubMed2005

Prenatal ischemia and white matter damage in rats.

Ischemia/reperfusion injury to the developing brain is a major cause of neurologic abnormalities in preterm infants. To investigate the underlying mechanisms, we modified a previously described rat model of unilateral uterine-artery ligation on the 17th embryonic day (E17). Growth retardation was taken as an index of in utero ischemia, and pups born with a birth weight more than 2 standard deviations below that of controls were compared with the same-litter, normal-growth control pups born from the nonligated horn. Prenatal ischemia probably associated with hypoxia and followed by reperfusion at birth induced white matter damage at a developmental stage corresponding to extreme prematurity in humans. On P0 (day of birth), growth-retarded pups exhibited lesions in the cingular white matter and internal capsule with increased counts of activated microglial cells for 2 weeks compared with controls. Astrogliosis was detected in the injured white matter. On P3, increased apoptotic cell death was seen in O4-positive preoligodendrocytes, which were abnormally scarce on P7. Defective myelination, as assessed by myelin-binding-protein labeling, was detected until adulthood. The diffuse white matter damage in growth-retarded rats replicated the main features of white matter damage in human preterm infants.

Animals↗
PubMedDate not supplied

Weekly alcohol consumption, brain atrophy, and white matter hyperintensities in a community-based sample aged 60 to 64 years.

OBJECTIVE: The objective of this study was to determine the association between weekly alcohol consumption and brain atrophy in adults aged 60 to 64 years. METHODS: Brain magnetic resonance imaging scans from 385 adults recruited through a community survey were analyzed. Automated segmentation and manual tracing methods were used to obtain brain subvolumes and automated methods were used to obtain quantification and localization of white matter hyperintensities. Visual measures of cortical atrophy were obtained as were data on health and lifestyle factors. Alcohol consumption was assessed with the Alcohol Use Disorders Identification Test. RESULTS: In men, weekly alcohol consumption had a positive linear association with ventricular volume and gray matter and a negative linear association with white matter. In women, weekly alcohol consumption had a nonlinear relationship with cerebrospinal fluid and white matter. Alcohol consumption was not associated with white matter hyperintensities, corpus callosum size, hippocampal or amygdala volumes in analyses adjusting for confounding variables. CONCLUSION: An association between alcohol consumption and brain atrophy is evident at the population level. In women, detrimental effects of alcohol on the brain appear to occur at lower levels of consumption. It remains possible that low levels of alcohol consumption have neuroprotective benefits but is clear that high levels of consumption are detrimental.

Alcohol Drinking↗
PubMed2005

White matter volume and cognitive dysfunction in early Huntington's disease.

BACKGROUND: Structural abnormalities of the striatum and cognitive impairments have consistently been shown in patients with Huntington's disease (HD). Fewer studies have examined other cerebral structures in early HD and potential associations with cognition. METHOD: Ten patients with early HD and 10 matched control subjects underwent magnetic resonance imaging to provide quantitative measures (volumes) of cortical gray and white matter and the caudate, putamen, and thalamus. Patients completed the Unified Huntington's Disease Rating Scale, including three cognitive tasks. RESULTS: Although striatal volumes were clearly reduced, white matter was also morphologically abnormal. Cortical gray matter volume was not significantly correlated with cognitive performance. However, the cognitive tasks were most highly correlated with cerebral white matter and, to a lesser degree, striatal volume. CONCLUSIONS: Cerebral white matter volume may be an important variable to examine in future studies of HD.

Adult↗
PubMed2006

White matter integrity of the whole brain is disrupted in first-episode schizophrenia.

Diffusion tensor imaging studies in schizophrenia have demonstrated lower diffusion anisotropy within white matter that provides information about brain white matter integrity. We have examined whether white matter is abnormal in first-episode schizophrenia by using diffusion tensor imaging. Twenty-one schizophrenic patients and healthy controls underwent diffusion tensor imaging scans that analyzed by using a rigorous voxel-based approach. We found that fractional anisotropy in white matter of the patients was lower than that in controls at the cerebral peduncle, frontal regions, inferior temporal gyrus, medial parietal lobes, hippocampal gyrus, insula, right anterior cingulum bundle and right corona radiata. These results suggested that white matter integrity of the whole brain was disrupted in early illness onset of schizophrenia.

Adolescent↗
PubMed2000

Fuzzy cold dark matter: the wave properties of ultralight particles.

Cold dark matter (CDM) models predict small-scale structure in excess of observations of the cores and abundance of dwarf galaxies. These problems might be solved, and the virtues of CDM models retained, even without postulating ad hoc dark matter particle or field interactions, if the dark matter is composed of ultralight scalar particles (m approximately 10(-22) eV), initially in a (cold) Bose-Einstein condensate, similar to axion dark matter models. The wave properties of the dark matter stabilize gravitational collapse, providing halo cores and sharply suppressing small-scale linear power.

Astronomy↗
PubMed2001

Constraints on the interaction between dark matter and Baryons from cooling flow clusters.

Other nongravitational heating processes are needed to resolve the disagreement between the absence of cool gas components in the centers of galaxy clusters revealed recently by Chandra and XMM observations and the expectations of conventional radiative cooling models. We propose that the interaction between dark matter and baryonic matter may act as an alternative for the reheating of intracluster medium (ICM) in the inner regions of clusters, in which kinetic energy of dark matter is transported to ICM to balance radiative cooling. Using the Chandra and XMM data, we set a useful constraint on the dark-matter-baryon cross section: sigma(xp)/m(x) approximately 1x10(-25) cm(2) GeV-1, where m(x) is the mass of dark matter particles.

Journal Article↗
PubMed2005

Cryptobaryonic dark matter.

It is proposed that dark matter could consist of compressed collections of atoms (or metallic matter) encapsulated into, for example, 20 cm big pieces of a different phase. The idea is based on the assumption that there exists at least one other phase of the vacuum degenerate with the usual one. Apart from the degeneracy of the phases we only assume standard model physics. The other phase has a Higgs vacuum expectation value appreciably smaller than in the usual electroweak vacuum. The balls making up the dark matter are very difficult to observe directly, but inside dense stars may expand absorbing the star and causing huge explosions (gamma ray bursts). The ratio of dark matter to ordinary matter is expressed as a ratio of nuclear binding energies and predicted to be about 5.

Journal Article↗
PubMed2006

Every person matters: enabling spirituality education for nurses.

AIMS AND OBJECTIVES: This paper aims to identify how the statutory requirements relating to spirituality in nurse education can be supported in preservice and in-service education, in the context of inter-professional working implied by every child matters (Department for Education and Skills (DfES) Every Child Matters: Change for Children. DfES, Nottingham DfES 2004a; Every Child Matters: Change for Children in Health Services. Department of Health, London 2004). BACKGROUND: The basis for this paper is an exploration of the current requirements relating to spirituality in nursing and the consequent requirements for training and education clarified in part through a consideration of parallel policies on spirituality in school education. Inter-professional work, for example, across health, social care and education professions, has a long history in nursing and the changes brought about by the every child matters policy initiative have given such inter-professional work a considerable boost. That policy change has encouraged consideration, in this article, of some common issues arising in nursing and school education professions. METHOD: This paper consists of a critical review of current and in-coming statutory requirements related to spirituality, nursing and nurse education, and a synthetic review of definitions of and approaches to meeting spiritual needs. CONCLUSION: The emergent relational framework for considering spirituality in nurse education acknowledges the ambiguity of spirituality and treats that ambiguity as in some ways enabling rather than constraining. RELEVANCE TO CLINICAL PRACTICE: It is not simply that nurse practice will be likely to change with respect to children. Every person will, in the terminology of the policy, 'matter': there is significant urgency to consideration of effective education and training provision.

Child↗
PubMed1999

Regional differences in diffusion abnormality in cerebral white matter lesions in patients with vascular dementia of the Binswanger type and Alzheimer's disease.

We investigated changes in water diffusion in the cerebral white matter of 14 patients with vascular dementia of the Binswanger type (VDBT) and ten patients with Alzheimer's disease (AD) with periventricular hyperintensity (PVH) lesions using diffusion-weighted magnetic resonance imaging (MRI) and studied the pathophysiological differences between white matter lesions found in these two conditions. Apparent diffusion coefficients (ADCs) in the anterior and posterior white matter and the genu and splenium of the corpus callosum were significantly higher in both groups of patients than in the 12 age-matched controls, and ADC values in VDBT and AD groups were almost the same. ADC ratios, defined as diffusion restricted perpendicular to the direction of nerve fibers, were also significantly higher in the patients than in the control subjects. However, there were regional differences in ADC ratios in the two conditions, with ratios in VDBT being higher in the anterior portions of the white matter but ratios in AD were higher in the posterior portions. The diffusion-weighted MRI technique may be useful in the differential diagnosis of VDBT and AD with white matter lesions.

Aged↗
PubMed2006

Severity of cerebral white matter lesions and infarcts in patients with transient or moderately disabling cerebral ischaemia: reproducibility of grading by neurologists.

Diffuse or multifocal ischaemic white matter lesions increase the risk of intracranial haemorrhage in patients using oral anticoagulants for secondary prevention after cerebral ischaemia of arterial origin. We studied whether neurologists could reliably assess the presence of these white matter abnormalities. As part of the European/Australian Stroke Prevention in Reversible Ischaemia Trial (ESPRIT), the severity of white matter lesions and presence of ischaemic lesions were twice assessed in a consensus meeting of three neurologists (from a pool of nine) as absent, moderate or severe, in a sample of 126 randomly selected CT or MRI scans. The neurologists were not aware of the duplicate grading. The degree of agreement between the first and second observation was calculated with kappa statistics. The kappa value for agreement between the first and second assessment of white matter lesions was 0.58 (95% CI 0.40-0.76). The kappa value for the presence of clinically relevant and/or irrelevant ischaemic lesions was 0.68 (95% CI 0.58-0.78). Clinicians can assess the presence of white matter lesions with sufficient reliability. Such assessment may prevent unnecessary risk with oral anticoagulation in secondary prevention after cerebral ischaemia of arterial origin, of which the efficacy is currently being assessed in ESPRIT.

Brain Infarction↗
PubMed2006

Brain MRI white matter lesions in migraine patients: is there a relationship with antiphospholipid antibodies and coagulation parameters?

Brain magnetic resonance imaging (MRI) studies in migraine patients have demonstrated lesions consisting of focal regions of increased signal intensity within the white matter. Antiphospholipid antibodies are known to have a role in many diseases including migraine. The aim of the present study was to ascertain the relationship between MRI-visualized cerebral focal hyperintense lesions and serum antiphospholipid antibody levels, as well as blood coagulation parameters in migraine patients. One hundred and two (77 females, 25 males, mean age 33.8 +/- 11.1) consecutive migraine patients and a control group of 94 (70 females, 24 males, mean age 33.2 +/- 10.8) healthy subjects were enrolled. All individuals underwent brain MRI. Complete blood examinations, autoantibodies, antiphospholipids antibodies including anticardiolipin and lupus anticoagulant (aCL, LAC), antithrombin III, Protein C and S serum levels were ascertained in the subjects who presented white matter lesions on MRI. Twenty-seven (26.4%) migraine patients and six (6.3%) healthy subjects in the control group showed focal regions of increased intensity signal within cerebral white matter (odds ratio 5.3, 95% CI: 1.98-16.36). In migraine patients with white matter lesions, antiphospholipid antibodies were not detected and serum levels of antithrombin III, and proteins C and S were normal. White matter lesions in migraine patients are fairly common. This finding is not associated with antiphospholipid antibodies or abnormal coagulation parameters. The significance of such lesions at present remains unclear.

Adult↗
PubMed1981

Free sterols of the rabbit optic nerve and cerebral white matter during ontogenic development.

Free sterol composition of the developing rabbit optic nerve was compared with that of the homologous cerebral white matter at corresponding stages of ontogeny. The sterols were detected and identified by means of combined gas-chromatography and mass spectrometry. The following free sterols were found in both the optic nerve and cerebral white matter: cholesterol, desmosterol, lanosterol, two dimethylsterols, which are probably 4,4-dimethyl-5 alpha-cholest-8,24-diene-3 beta-ol, with a molecular weight of 412, and 4 alpha, 14 alpha-dimethyl-5 alpha-cholest-7-ene-3 beta-ol, with a molecular weight of 414 and probably cholestene, with a molecular weight of 368. The sterol spectrum of the developing optic nerve differed not only from that of the mature nerve but also from that of age-matched white matter of the rabbit brain. The tri- and dimethyl-sterols, detected for the first time in the rabbit optic nerve and cerebral white matter, are natural components of the developing nervous tissue but they were not found in the mature nerve nor in cerebral white matter.

Animals↗
PubMed1995

Lesion localization in periodic lateralized epileptiform discharges: gray or white matter.

We analyzed the results of neuroimaging studies in patients with periodic lateralized epileptiform discharges (PLEDs) or bilateral independent periodic lateralized epileptiform discharges (BIPLEDs) for localization of lesions in gray or white matter to determine if "cortical isolation" is a critical mechanism in the pathogenesis of this phenomena. We assessed 32 patients who had undergone computed tomography (CT) exclusively and 8 patients who had undergone magnetic resonance imaging (MRI) with or without CT. The superior resolution necessary for adequate lesion localization allowed use of only the MRI scans from the 8 patients. Six patients had scans with cortical and subcortical gray and white matter lesions, and 1 patient had a cortical gray matter lesion only. One patient had an indeterminate scan. No patient had white matter lesions only. Our findings in patients with PLEDs and BIPLEDs correlate with postmortem data in patients with generalized periodic EEG patterns that show consistent localization of lesions in the gray matter. These findings do not support cortical isolation as the critical or sole mechanism in PLEDs or BIPLEDs.

Adult↗
PubMed2006

A magnetization transfer MRI study of deep gray matter involvement in multiple sclerosis.

BACKGROUND/PURPOSE: Gray matter involvement in multiple sclerosis (MS) is of growing interest with respect to disease pathogenesis. Magnetization transfer imaging (MTI), an advanced MRI technique, is sensitive to disease in normal appearing white matter (NAWM) in patients with MS. DESIGN/METHODS: We tested if MTI detected subcortical (deep) gray matter abnormalities in patients with MS (n= 60) vs. age-matched normal controls (NL, n= 20). Magnetization transfer ratio (MTR) maps were produced from axial proton density, conventional spin-echo, 5 mm gapless slices covering the whole brain. Region-of-interest-derived MTR histograms for the caudate, putamen, globus pallidus, thalamus, and NAWM were obtained. Whole brain MTR was also measured. RESULTS: Mean whole brain MTR and the peak position of the NAWM MTR histogram were lower in patients with MS than NL (P < .001) and mean whole brain MTR was lower in secondary progressive (SP, n= 10) than relapsing-remitting (RR, n= 50, P < .001) patients. However, none of the subcortical gray matter nuclei showed MTR differences in MS vs. NL, RR vs. SP, or SP vs. NL. CONCLUSIONS: The MTI technique used in this cohort was relatively insensitive to disease in the deep gray matter nuclei despite showing sensitivity for whole brain disease in MS. It remains to be determined if other MRI techniques are more sensitive than MTI for detecting pathology in these areas.

Adult↗