bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lymphokine induction of rat microglia multinucleated giant cell formation
Authors: Lee Thomas T. , Martin Fredricka C. , Merrill Jean E. 
Published: January 2005

AbstractMultinucleated giant cell formation (MNGC) occurs in central nervous system AIDS. The mechanism of fusion of microglia in these cases is unknown. We investigated the ability of lymphokines to induce fusion and found that interleukin‐3 (IL‐3), interleukin‐4 (IL‐4), gamma interferon (γ‐IFN), and granulocyte‐macrophage colony stimulating factor (GM‐CSF) induced MNGC formation in cultures of rat microglia in vitro. The diacylglycerol analogue phorbol myristate acetate (PMA) also induced MNGC. Interleukin‐1 (IL‐1), interleukin‐6 (IL‐6), and tumor necrosis factor alpha (TNFα) failed to induce fusion. Preincubation of the IL‐3 treated cultures with anti‐IL‐3, anti‐leukocyte function associated antigen‐1 (LFA‐1) α‐chain (CD11a), and anti‐intercellular adhesion molecule‐1 (ICAM‐1) inhibited cell fusion. Antibody to polymorphic Class II major histocompatibility complex (MHC) determinants also inhibited MNGCs. Cell surface LFA‐1 was predominantly observed on MNGC, suggesting that LFA‐1 expression is involved in microglia fusion. We thus propose that MNGC formation of microglia result from the effects of T cell‐derived cytokines probably through the induction of cell surface adhesion molecules. © 1993 Wiley‐Liss, Inc.
Myelination by mature ovine oligodendrocytes in vivo and in vitro: Evidence that different steps in the myelination process are independently controlled
Authors: Ludwin Samuel K. , Szuchet Sara 
Published: January 2005

AbstractThe ability of isolated mature post‐myelination ovine oligodendrocytes to myelinate was investigated in tissue culture and in vivo. In culture, although the cells adhered preferentially to rat dorsal root ganglia (DRG) axons, sent out processes that encircled and wrapped them, proliferated, and synthesised myelin proteins (MBP), no myelination was found. This failure to find myelination occurred despite the fact that the oligodendrocytes both in the present experiments and in previous studies elaborated membranous structures that have been shown chemically and structurally to be similar to normal central nervous system myelin. These findings contrasted with those seen when neonatal rodent glial cells were added to similar DRG neuron cultures, in which myelination readily occurred. When the same adult ovine oligodendrocytes were transplanted into the brains of Shiverer mice, normal compact myelin was formed, proving that the cells were capable of myelination and suggesting that cross‐species incompatibility was probably not a major factor in the lack of myelination in vitro.It is possible that the failure of ovine oligodendrocytes to myelinate DRG axons is due either to the relatively low number of supporting glial cells, such as astrocytes or microglia which may be necessary for satisfactory myelination, or that some other factor in the microenvironment is lacking; in any event, these results point to the complexity of oligodendrocyte‐axon interactions. It is clear that each of the events, from adherence to proliferation to wrapping and the myelin compaction may be under the control of a different signal and may operate through a distinct mechanism, even though each process is dependent on the other. The results also point to the potential usefulness of this model system for deciphering such signals and mechanisms. © 1993 Wiley‐Liss, Inc.
Axons modulate the expression of transforming growth factor‐betas in Schwann cells
Authors: Scherer Steven S. , Kamholz John , Jakowlew Sonia B. 
Published: January 2005

AbstractWe have investigated the expression of transforming growth factor (TGF)‐β1,‐β2, and ‐β3 in developing, degenerating, and regenerating rat peripheral nerve by immunohistochemistry and Northern blot analysis. In normal adult sciatic nerve, TGF‐β1, ‐β2, and ‐β3 are detected in the cytoplasm of Schwann cells, and the levels of TGF‐β1 and ‐β3 mRNAs are constant during post‐natal development. When sciatic nerves are transected to cause axonal degeneration and prevent axonal regeneration, the level of TGF‐β1 mRNA in the distal nerve‐stump increases markedly and remains elevated, whereas the level of TGF‐β3 mRNA falls modestly and remains depressed. When sciatic nerves are crushed to cause axonal degeneration and allow axonal regeneration, the level of TGF‐β1 mRNA initially increases as axons degenerate, and then falls as axons regenerate. TGF‐β2 mRNA was not detected in developing or lesioned sciatic nerves at any time. Cultured Schwann cells have high levels of TGF‐β1 mRNA, the amount of which is reduced by forskolin, which mimicks the effect of axonal contact. These data demonstrate that Schwann cells express TGF‐β1, ‐β2, and ‐β3, and that TGF‐β1 and ‐β3 mRNA predominate over TGF‐β2 mRNA in peripheral nerve. Axonal contact and forskolin decrease the expression of TGF‐β1 in Schwann cells. © 1993 Wiley‐Liss, Inc.
Differential activation of microglia and astrocytes in aniso‐ and isomorphic gliotic tissue
Authors: Fernaud‐Espinosa Isabel , Nieto‐Sampedro M. , Bovolenta P. 
Published: January 2005

AbstractReactive astrocytes and microglial cells are both involved in the formation of gliotic tissue. Using immunohistochemical markers, we have compared the response of both these cell types after two different kinds of damage in the brain: traumatic injury (anisomorphic gliosis) and neurotoxic induced lesion (isomorphic gliosis), in two distinct regions of the brain, the cortex and the hippocampus. We show that the time course and the relative contribution of astrocytes and microglial cells differ greatly in the two kinds of lesions. While in anisomorphic gliosis there is little activation of endogenous microglial cells independently of the brain region damaged, these cells contribute in large measure and for prolonged periods of time to the formation of isomorphic gliotic tissue. Astrocytes are quickly activated at the border of anisomorphic lesions, and after 3 days they already occupy an extensive portion of the brain parenchyma. However, after 1 month, they are found restricted to a thin strip at the lesion boundary. In contrast, after an isomorphic lesion, astrocytes become reactive around the site of neuronal cell loss but not at the site of the lesion itself. Only after 2 weeks do they totally invade the damaged region, persisting for at least 1 month. Such differences are observed independently of the brain region damaged.These results suggest that the cellular, and therefore the molecular, composition of gliotic tissue depends on the type of insult the CNS has suffered. © 1993 Wiley‐Liss, Inc.
Native astrocytes do not migrate de novo or after local trauma
Authors: Hatton James D. , Finkelstein Jeremy P. , Sang U Hoi 
Published: January 2005

AbstractWhile transplanted astrocytes migrate in specific patterns in therecip‐ient brains, it is not known whether native astrocytes behave similarly. The ability of normal astrocytes to migrate under non‐transplant condition was therefore explored. Native astrocytes were labelled in situ with fluorescent latex beads. These latex spheres were actively endocytosed by astrocytes in vitro, and it was therefore anticipated that these spheres would also be endocytosed by native astrocytes exposed to them. Labelling was accomplished by dissecting the pia mater away from a small region of the cerebral cortex and overlaying the area with Gelfoam containing fluorescent beads. After 2–4 h, the Gelfom was removed and the wound was cloesd. At the end of 2–4 weeks, manipulated brains were harvested for fluorescence microscopy. In this analysis, fluorescent polyspheres had been taken up by both pial fibroblasts and astrocytes at the pial‐glial margin. Labelled astrocytes [identified by glial fibrillary acidic protein (GFAP) staining] were neither hyperplastic nor hypertrophic. They were confined to the area of the original labelling site, and did not migrate either laterally across the pial margin or ventrally into the cortical layers. Knife wounding at the time of label application, either in the region of the label or distant from it, produced reactive astrocytes that were hypertrophic. These cells also did not migrate from the label site. These results suggest that astrocytes labelled by this method do not migrate in the absence of some transplant‐derived stimulus even when stimulated by local wounding. © 1993 Wiley‐Liss, Inc.
Lines of glial precursor cells immortalised with a temperature‐sensitive oncogene give rise to astrocytes and oligodendrocytes following transplantation into demyelinated lesions in the central nervous system
Authors: Trotter Jacqueline , Crang A. John , Schachner Melitta , Blakemore William F. 
Published: January 2005

AbstractImmortalised lines of murine glial precursor cells expressing the neomycin resistance gene and a temperature‐sensitive mutation of the SV 40 T oncogene were established from cultures of oligodendrocytes and precursor cells infected with a replication‐incompetent, helper‐free retrovirus. At the permissive temperature (33°C), they could be continually propagated in vitro and cells were present expressing the 04 antigen specific for glial precursor cells and oligodendrocytes. At 38°C, where the expression of the T antigen is down regulated, cell division largely ceased. During early passage in vitro, limited differentiation to a more mature phenotype, as evidenced by expression of GFAP and the oligodendrocyte marker O1 was observed at both 33°C and 38°C. When transplanted into demyelinating lesions in the spinal cords of adult rats early passages of the lines yielded myelin‐forming oligodendrocytes and astrocytes. Cells from later passages of the lines although failing to synthesise myelin still associated specifically with the demyelinated axons. These experiments demonstrate the retention of physiological properties of these oncogene‐carrying glial cells when transplanted in vivo and suggest that such immortalised populations can be used for the isolation of molecules regulating glial cell function. © 1993 Wiley‐Liss, Inc.
Morphological heterogeneity of rat oligodendrocytes: Oligodendrocytes: Electron microscopic studies on serial sections
Authors: Bjartmar Carl , Hildebrand Claes , Loinder Kristina 
Published: January 2005

AbstractThe microanatomy of ensheathing and early myelinating rat oligodendrocytes was analyzed through electron microscopic examination of serial sections. The study included cells in the spinal cord (SC) ventral funiculus and the corpus callosum (CC), containing early myelinating, prospective large axons and late myelinating, prospective small axons, respectively. The results show that ensheathment commences fetal day (F) 19 in the SC and 12 days postnatally (P12) in the CC. By then, multipolar SC and CC oligodendrocytes provide axons with uncompacted cytoplasmic sheaths. The average number of axons ensheathed by each such cell was 7 in the SC and 13 in the CC. The mean diameter of the ensheathed axons was 0.69 μm in the SC and 0.36 μm in the CC. The formation of compact myelin had clearly been initiated at birth in the SC and at P17 in the CC. At that stage, the mean number of myelinated axons per analyzed oligodendrocyte was 3 in the SC and 15 in the CC. The mean diameter of the myelinated axons was 1.02 μm in the SC and 0.54 μm in the CC. These observations show that myelin‐related rat oligodendrocytes are morphologically heterogeneous. It also seems that this heterogeneity is related to time of onset of myelination and prospective axon diameter. Further, the data suggest that some oligodendrocytes reduce the number of sheaths initially elaborated before formation of compact myelin. © 1994 Wiley‐Liss, Inc.
Postural disturbance and psychological symptoms amongst elderly people living at home
Authors: Downton J. H. , Andrews K. 
Published: January 2005

AbstractMany writers have commented on the frequency with which old people express fear of falls but this fear has not been quantified. As part of an epidemiological study of falls in the elderly living at home, 203 people over 75 years of age were questioned about falls experienced in the previous 12 months, fear of falling and symptoms of dizziness, and assessments were made of their mood, cognitive function, physical state, dependence and mobility. Fear of falling affected the same proportion of subjects as falls themselves (42.4%) and although there was an association between fear of falling and having experienced falls, a third of non‐fallers limited their activity because they were frightened of falling. Falls, fear of falling and subjective dizziness were strongly associated with anxiety and depression. Subdivision of fallers into outside and inside fallers or those who had fallen because of trips and ‘non‐trip’ fallers produced groups which differed in their physical frailty, mobility and dependence, but even the otherwise healthy and independent outside fallers and ‘trip’ fallers had high anxiety and depression scores. This may be an indication of the psychological impact of falls.
Psychotropics prescribed to the US elderly in the early and mid 1980s: Prescribing patterns of primary care practitioners, psychiatrists, and other physicians
Authors: Larson David B. , Lyons John S. , Hohmann Ann A. , Beardsley Robert S. , Hidalgo Julia 
Published: January 2005

AbstractPrimary care practitioners are significant providers of mental health services to older Americans. The most common mental health service provided by primary care practitioners to this segment of the population is psychotropic drugs. A USA national data base was analyzed to compare the psychotropic prescribing patterns of primary care practitioners with psychiatrists and other office‐based specialists in both the early and mid 1980s. Prescribing patterns for six different classes of psychotropics were contrasted for patients 55 years of age and older and those 15‐54. Results indicate that primary care practioners were by far the largest prescribers of psychotropics for patients 55 and over at both time periods. This pattern held for most of the individual psychotropic drug classes. In contrast to psychiatrists, primary care practitioners infrequently included a mental disorder diagnosis when they prescribed a psychotropic drug. In addition, primary care practitioners included a mental disorder diagnosis less frequently when they prescribed for the older group than when they prescribed for the younger group. These findings may be used to benefit the training of non‐psychiatrist physicians in the diagnosing and treating of mental health disorders found among older adults.
The cognitive drug research computerized assessment system for demented patients: A validation study
Authors: Simpson P. M. , Surmon D. J. , Wesnes K. A. , Wilcock G. K. 
Published: January 2005

AbstractDemeneted elderly patients (N = 23, aged 60–94) and controls (N = 22, aged 52–86) performed a version of the Cognitive Drug Research computerized Assessment System comprising cognitive tasks measuring choice reaction time, vigilance, and the sensitivity and speed of digit, word and picture recognition. The demented patients showed large and highly significant impairments in the speed of choice reaction and in the sensitivity and speed of all memory tasks. Correlations between the various scores from the computerized tests and those from the Folstein Mini‐Mental State Examination, the Kendrick Battery and the Kew were high and significant, implying that the computerized tasks measure similar aspects of cognition to procedures used to assess dementia. In 16 memory clinic patients, high correlations were also found between the Stockton Rating Scale and the scores from the computerized tests, suggesting that the latter have relevance to the general behavioural condition of the patients. These findings, together with evidence of good test‐retest reliability, indicate that, for demented patients, the utility of this system to assess cognitive change should be comparable to that of previous versions used with the young and with non‐demented elderly.
The detection of psychiatric morbidity and its effects on outcome in acute elderly medical admissions
Authors: Ramsay Rosalind , Wright Penelope , Katz Anthony , Bielawska Celia , Katona Cornelius 
Published: January 2005

AbstractThis study examines the point prevalence of psychiatric morbidity in patients admitted to acute geriatric care, the performance of screening questionnaries in detecting psychiatric morbidity and the relationship between psychiatric morbidity and outcome (in terms of length of hospital admission and mortality) after controlling for severity of physical illness. In a sample of 119 consecutive admissions, 65 (61%) of the 106 patients assessed had dementia, while nine (10%) of the 88 assessed had a diagnosis of depression and a further 35 (40%) significant depressive symptoms, and 22 (20%) of the 106 assessed had delirium. Screening with the Mini‐Mental State Examination had 81% sensitivity and 83% specificity for dementia. The Geriatric Depression Scale (GDS) had 74% sensitivity and 72% specificity for depressive symptoms; both the GDS and General Health Questionnaire had 100% sensitivity for depressive illness. Mortality was significantly higher in the delirious (62%) than in the non‐delirious (14%,p>0.001) and in the severely demented (65%) than the mildly demented (29%) and non‐demented (15%,p>0.001) subjects. For delirium this effect was found to be independent of the severity of physical illness. Patients with severe dementia had significantly longer hospital admissions (p>0.02). No relationship was found between depression and outcome.
Modification of the mini‐mental state examination for use with the elderly in a non‐western society. Part II: Cutoff points and their diagnostic validities
Authors: Park Jong‐Han , Park Young Nam , Ko Hyo Jin 
Published: January 2005

AbstractDiagnostic power of the Korean version of the Mini‐Mental State Examination (MMSE‐K) (Park and Kwon, 1990) for DSM‐III‐R dementia was studied in 406 persons aged 60 years or more from three sources. Psychiatric clinic patients (N=177) were diagnosed using standard clinical procedures, laboratory tests and psychological tests; in residential home elderly (N=128) consensus diagnoses were reached by two psychiatrists after joint interviews using the CAMDEX (Roth et al., 1988) including physical examinations but without laboratory tests; and members of psychiatric patients' families (N=101) were diagnosed after a brief psychiatric interview and assessment of activities of daily living by one psychiatrist. At the cutoff point of 24/23 of MMSE‐K score, sensitivity was 92.0% and specificity 91.5%. 23.9% of demented people and 39.3% of non‐demented obtained similar scores between 20 and 26. With the introduction of the arbitrary criteria of ‘questionable dementia’ (MMSE‐K score 21‐24) the false positive rate was reduced to 1% and the false negative rate to 3%. 74% of males with ‘questionable dementia’ scores were clinically demented while only 12% of females with the same scores were demented.
Risk factors for clinically diagnosed alzheimer's disease
Authors: Baker F. M. , Jordan Barry , Barclay Laurie , Schoenberg Bruce S. 
Published: January 2005

AbstractThirty‐six cases of patients with clinically diagnosed Alzheimer's disease (CDAD) were identified from the dementia clinic of the Burke Rehabilitation Center. Controls were identified from the rehabilitative units of the same facility. Controls were matched for age within 5 years, sex, race, marital status, status at time of surrogate interview (case alive or dead), and the absence of dementia.Birth in an urban versus a rural environment (OR = 16), childhood in an urban versus a rural environment (OR = 9.5), and adult life in an urban versus a rural environment (OR = 16) were associated with an increased risk to develop CDAD. The daily or weekly use of beef/pork (OR = 4) and saccharin (OR = 2.25) were associated with an increased risk to develop CDAD as was the ownership of a pet rabbit (OR = 2). Further, a history of other cancers (OR = 3) in cases with CDAD was associated with an increased risk to develop CDAD. Type A personality characteristics were found to be associated with an increased risk (‘ate fast’ (OR = 3.5)), ‘not relaxed and easy‐going’ (OR = 2.25), ‘always rushed’ (OR = 2.00) to develop CDAD as was a history of depression (OR = 2). Due to the small sample size, statistically meaningful confidence intervals could not be calculated and our results must be confirmed in larger samples of case control pairs.
The depressed elderly chinese living in the community: A five‐year follow up study
Authors: Kua Ee Heok 
Published: January 2005

AbstractIn 1985 a random sample of 612 elderly Chinese aged 65 and over living in the community in Sigapore was interviewed using the GMS‐AGECAT package. The survey identified 35 cases and 28 subcases of depressive disorder. Five years later only 31 cases could be traced; in this subsample 10 were still depressed (32.3%), eight had recovered (25.8%), five were categorized as subcases of depression (16.1%), two were diagnosed as anxiety disorder (6.5%), one case was diagnosed as having dementia (3.2%) and five had died (16.1%). Only 25 subcases from the initial study could be traced; of these, three had developed depression (12.0%), 15 had recovered (60.0%), four remained as subcases (16.0%) and three had died (12.0%).
Application of the scaled subprofile model to functional imaging in neuropsychiatric disorders: A principal component approach to modeling brain function in disease
Authors: Alexander Gene E. , Moeller James R. 
Published: January 2005

AbstractRecent advances in functional neuroimaging have presented a challenge to traditional statistical methods in characterizing the effects of neuropsychiatric illness on brain function. The most common approach for analyzing regional group differences has relied on t‐tests with significance thresholds selected to reduce the potential effect of multiple statistical tests. Regional covariance analysis offers an alternative to this threshold‐based, group difference approach by identifying the functional interactions among brain regions that can be spatially distributed throughout the brain. The Scaled Subprofile Model (SSM) is one form of regional covariance analysis that has been applied to the study of patient groups. Based on a modified principal component analysis, the SSM offers a method for modeling regionally specific patterns of brain function whose expression can be evaluated between groups and validated against clinical measures of patient disease severity and neuropsychological test scores. We review the application of the SSM, to date, in studies of the effects of neurological and psychiatric illness on brain function, including a discussion of SSM methodology and its application to the study of resting state functional neuroimaging in patient groups. SSM analyses applied to studies of Alzheimer's disease, Parkinson's disease, major depressive disorder, AIDS dementia complex, and neoplastic disease each identified functionally specific topographic effects that were associated with clinical disease severity. The results of the SSM analyses suggest that neuropsychiatric disorders may alter functional networks or systems of neural activity in ways that can be expressed as regional covariance patterns in resting functional imaging data. © 1994 Wiley‐Liss, Inc.