bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional properties of retinal Müller cells following transplantation to the anterior eye chamber
Authors: Small Rochelle K. , Watkins Brynmor A. , Munro Peter M. , Liu Dandan 
Published: January 2005

AbstractTwo types of glial cells occur in the retina, Müller cells and astrocytes. These cells share several structural features such as extending endfeet onto blood vessels of the retina. Retinal vessels express a tight blood‐retinal barrier which is comparable to the blood‐brain barrier (BBB) of the CNS. While astrocytes have been implicated in the induction of the BBB, the role of Müller cells in the blood‐retinal barrier is unknown. To determine if Müller cells are capable of influencing vascular permeability, we have prepared Müller cells that are free of astrocytes and transplanted them to a peripheral target, the anterior eye chamber. Müller cells were identified 2 weeks to 3 months after injection and were predominantly localized within the connective tissue of the ciliary body. The Müller cells occurred as dense clusters of cells closely associated with ciliary blood vessels. The ciliary vessels adjacent to Müller cells were freely permeable to circulating horseradish peroxidase (HRP), suggesting that Müller cells did not induce tight barrier properties from these leaky peripheral vessels. In contrast, cortical astrocytes injected into the anterior eye chamber preferentially formed a monolayer on the anterior surface of the iris, a region known to contain blood vessels that are impermeable to circulating tracers (e.g., Raviola, Exp Eye Res [Suppl] 25:27, 1977). Müller cells were rarely associated with the iris and the few cells that were present were located deep within the iris stroma rather than on the surface. The behaviour of guinea pig Müller cells transplanted to the anterior eye chamber contrasts sharply with that of cortical astrocytes in terms of: (1) the ocular compartment to which Müller cells migrate; (2) the tissue invasiveness of the cells; and (3) the degree of permeability of blood vessels adjacent to transplanted cells. The results of this study emphasize the functional distinctness of the two types of retinal glia and suggest that Müller cells from guinea pig retina may not be active in modifying the permeability properties of peripheral blood vessels, a function that has been suggested for astrocytes.
Interleukin‐1 and tumor necrosis factor‐mediated regulation of C3 gene expression in human astroglioma cells
Authors: Barnum Scott R. , Jones Jennifer L. , Benveniste Etty N. 
Published: January 2005

AbstractIn this report, we show that in the human astroglioma cell line D54‐MG, both interleukin‐1 (IL‐1β) and tumor necrosis factor‐alpha (TNF‐α) enhance C3 gene expression in a time‐ and dose‐dependent manner. Kinetic analysis demonstrates that after 96 h, C3 mRNA levels increase approximately 30‐fold and 20‐fold in response to IL‐1β or TNF‐α, respectively. C3 protein production increases proportionally, reaching levels 36‐fold and 18‐fold higher than untreated controls upon exposure to IL‐1β or TNF‐α, respectively. D54‐MG cells require a minimal 1 h exposure to IL‐1β in order to enhance C3 gene expression significantly, while 4 to 8 h are required for TNF‐α. Simultaneous treatment of D54‐MG cells with IL‐1β and interferon‐gamma (IFN‐γ) resulted in an additive increase in both C3 mRNA and protein expression, a finding not seen with the combination of TNF‐α and IFN‐γ. Primary rat astrocytes also express increased C3 mRNA levels after 48 h in response to IL‐1β (5.3‐fold increase) and TNF‐α (7‐fold increase), while an additive effect was observed upon simultaneous treatment with both IL‐1β and IFN‐γ. In the central nervous system (CNS), endogenous complement and cytokine production by astrocytes, and enhancement by IFN‐γ, a product of activated T cells often seen in the CNS in neural autoimmune disease, may contribute to the pathogenesis of inflammatory demyelinating diseases such as multiple sclerosis.
Infusion of cytosine‐arabinoside into the cerebrospinal fluid of the rat brain inhibits the microglial cell proliferation after hypoglossal nerve injury
Authors: Svensson Mikael , Aldskogius Håkan 
Published: January 2005

AbstractThe present study describes a method to inhibit selectively the microglial cell proliferation following peripheral nerve injury. Continuous infusion of cytosine‐arabinoside (ARA‐C) from an osmotic minipump to the fourth ventricle or cisterna magna completely blocks the proliferation of microglial cells that normally occurs following hypoglossal nerve transection. This treatment had no significant effect on other glial cells or on the expected morphological changes in the axotomized hypoglossal motorneurons. The method opens up new possibilities for analyzing the functional role of the axotomy‐induced microglial cell reaction.
Extracellular matrix modulates the proliferation of rat astrocytes in serum‐free culture
Authors: Nagano Nobuhisa , Aoyagi Masaru , Hirakawa Kimiyoshi 
Published: January 2005

AbstractThe mechanism of glial proliferation in the developing nervous system, as well as in response to injury, inflammation, and tumor invasion, is unknown. Several growth factors and extracellular matrices have been shown to stimulate the proliferation of cultured cells of various origin, including astrocytes. We investigated the effect of extracellular matrix components, including fibronectin (FN), laminin (LN), and collagen types I and IV, on the growth of astrocytes during stimulation by various growth factors. When astrocytes were grown on FN‐ and LN‐coated wells in a serum‐free, chemically defined medium, their increase in number significantly exceeded that of cells grown on plastic wells. The addition of platelet‐derived or basic fibroblast growth factor to cells cultured on FN ‐ or LN ‐coated wells significantly potentiated astrocyte proliferation. The collagen preparations had no such effect. These observations indicate that FN and LN have a fundamental part in converting the quiescent astrocyte into the proliferating phenotype, which may be required for remodeling damaged brain tissues in vivo. © 1993 Wiley‐Liss, Inc.
Differential expression of carbonic anhydrase isozymes in microglial cell types
Authors: NóGrádi Antal 
Published: January 2005

AbstractMicroglial cells have been shown to express carbonic anhydrase. Using carbonic anhydrase histochemistry and immunohistochemistry, different types of cen‐tral nervous system microglial cells were detected, which expressed two main carbonic anhydrase (CA) isozymes during the early postnatal stage of development and after peripheral nerve injury in the spinal cord of adult rats. Amoeboid and reactive microglial cells were heavily immunostained for CA‐II and CA‐III and showed colocalization with complement receptor type 3 and Griffonia Simplicifolia B4 isolectin. Resting microglial cells in the brain and spinal cord showed faint CA‐III staining and were negative for CA‐II. These results show that not only CA‐II, but also CA‐III isozyme is represented in the central nervous system and carbonic anhydrase activity may correlate with metabolic and immunological changes of microglial cells. These data also further strengthen the idea of the mesodermal origin of central nervous system macrophages. © 1993 Wiley‐Liss, Inc.
Migration of newly generated neurons upon ependymally derived radial guide cells in explant cultures of the adult songbird forebrain
Authors: Goldman Steven A. , Lemmon Vance , Chin Steven S.‐M. 
Published: January 2005

AbstractThe adult songbird forebrain undergoes neuronal production through‐out adulthood, with the production of new neurons in discrete regions of the neostriatal ventricular zone. Upon mitogenesis, these new neurons migrate into the subjacent brain parenchyma along radially directed guide fibers. In long‐term ventricular zone explant cultures, derived from the higher vocal center of the adult canary, newly migratory neurons were found to associate preferentially with a characteristic substrate cell type. These small, parvonuclear substrate cells formed tightly packed epithelioid sheets, in which ciliated ependymal cells were common, as recognized by both live observation and electron microscopy. A subpopulation of these cells was immunostained by monoclonal antibody 3A7, which preferentially stains the guide fiber network of the adult avian brain. These 3A7+ cells included ependymal cells and bipolar radial cells, as well as morphologically defined astrocytes. As they matured in vitro, the 3A7+ bipolar radial cells extended long, unbranching fibers, which ultimately traversed the culture substrate. Like ependymal cells, they supported neuronal migration. These cells were likely homologous to radial guide cells in vivo. Thus, neuronal migration in adult avian forebrain culture occurred upon guide cells of ependymal derivation. © 1993 Wiley‐Liss, Inc.
Interleukin‐6 production by brain tissue and cultured astrocytes infected with Theiler's murine encephalomyelitis virus
Authors: Rubio Nazario , Sierra Angeles 
Published: January 2005

AbstractTheiler's murine encephalomyelitis virus (TMEV) is known to interact with cells of the central nervous system (CNS). Here we report that, interestingly, it is a potent inductor of interleukin‐6 (IL‐6) in the CNS of infected animals and in pure cultures of astrocytes. Maximal IL‐6 gene transcription in glial cells, as detected by bioassay and ELISA, was observed at 6 and 24 h after infection. Astrocytes from both SJL/J and Balb/c (strains of mice susceptible and resistant, respectively, to TMEV‐induced demyelination) produced similar amounts of IL‐6, measured in tissue culture supernatants. These results indicate that although an immunomodulatory effect can be exercised by IL‐6 synthesized by astrocytes, it does not play a crucial role in immune‐mediated demyelination induced by TMEV. © 1993 Wiley‐Liss, Inc.
Interactions of living astrocytes in vitro: Evidence of the development of contact spacing
Authors: Dreher Zofia , Tout Simon , Stone Jonathan 
Published: January 2005

AbstractWe have studied the behaviour of living, process‐bearing astrocytes in vitro, observing groups of cells at daily intervals for up to 7 days. Each cell initially formed two processes, appearing bipolar in shape, and with further time in culture, grew additional processes and appeared stellate. As their processes grew, the interactions between astrocytes underwent characteristic changes. While bipolar, the cells appeared to avoid making contact, lying parallel to each other. As they became stellate, the astrocytes made extensive contact with neighbours, gradually forming extended, contacting networks in which their somas were regularly spaced (as previously described). The interactions which led to the establishing of such arrays were also evident. If two cells were initially close or adjacent, they extended short processes to contact each other; then, as their processes grew, their somas moved apart, until they were separated by 60‐120 μm. If two cells were initially well separated, each directed processes towards the other until contact was made, often with striking precision, and their somas then moved together, until they were separated by 60‐120 μm. These behaviours of contact, separation, and approach caused astrocytes to form clusters, within which their somas appeared regularly spaced, and may represent the interactions which occur among astrocytes during normal development to produce the regularly spaced arrays of astrocytes described in earlier studies of intact central nervous tissue. © 1994 Wiley‐Liss, Inc.
Glial hypertrophy is associated with synaptogenesis following motor‐skill learning, but not with angiogenesis following exercise
Authors: Anderson Brenda J. , Li Xiangchun , Alcantara Adriana A. , Isaacs Krystyna R. , Black James E. , Greenough William T. 
Published: January 2005

AbstractRats reared from weaning in a complex environment have an increase in (1) glial surface area, (2) capillary volume, and (3) the number of synapses, per neuron. In that paradigm it has not been possible to determine whether the glial increase more closely correlates with the increase in synaptic numbers or with angiogenesis. More recently we have found that rats that exercised had an increase in the density of capillaries without an increase in the synaptic numbers, whereas rats that learned new motor skills had a greater number of synapses per neuron without an increase in the density of capillaries. Those findings provided the opportunity to investigate whether changes in glial volume in the cerebellum correspond to changes in the number of synapses or in capillary volume. Glial area fraction estimates were obtained using point counts on electron micrographs from the previous studies. The skill learning group had a greater volume of molecular layer per Purkinje cell, and also a greater volume of glia per Purkinje cell, than rats in either an inactive group or rats in two exercise groups. No significant differences were found in glial volume per synapse and glial volume per capillary across groups, although there was a tendency for glial volume per capillary to be lower in the exercise groups. The data indicate that glial volume correlates with synaptic numbers and not with capillary density. © 1994 Wiley‐Liss, Inc.
A one‐year prognosis of dysthymic disorder and major depression in old age
Authors: Kivelä Sirkka‐Liisa , Pahkala Kimmo , Laippala Pekka 
Published: January 2005

AbstractA prospective follow‐up of 199 elderly (60 + yr) patients (65 men and 134 women) suffering from dysthymic disorder and 42 elderly (60 + yr) patients (13 men and 29 women) suffering from major depression is described. The mean duration of the follow‐up was 15.3 ± 4.3 months for dysthymic men, 15.2 ± 4.4 months for dysthymic women, 15.3 ± 4.0 months for major depressive men and 14.0 ± 4.2 months for major depressive women. Forty‐three per cent of the dysthymic men, 38% of the dysthymic women, 39% of the major depressive men and 48% of the major depressive women had a good outcome. In dysthymic men, few visiting contacts were associated with poor outcome. In dysthymic women, poor outcome was associated with many depressive symptoms, low social participation, not living alone, low self‐perceived health, intensive diurnal variation of symptoms, low interest in work and activities, low sexual interest, and hypochondrial and compulsive symptoms. In major depressive men, no variable was associated with outcome. In major depressive women, poor outcome was associated with diabetes mellitus, suicidal ideas or attempted suicide, and psychomotor agitation or psychomotor retardation.
Dependency in old age: A comparison of mental and physical factors
Authors: Kay D. W. K. , Holding T. A. , Jones B. , Littler S. 
Published: January 2005

AbstractThe lavel of dependency of 412 patients aged 70 years or over living in hospitals, nursing homes or sheltered accommodation (N=312) or receiving care from the domiciliary nurising services (N=100) and of 100 elderly people living in the community in Hobart, Tasmania, was assessed using a version of the CARE schedule. Therespective roles of mental and physical factors were examined using other CARE intems and after administering the Geriatric Mental Status schedule and the Wechsler Memory Scale. Rank‐order correlations and log‐linear analyses indicated that physical impairment affecting mobility and upper limb function and cognitive impairment due to dementia were about equally strongly related to the level of dependency;at least moderate degrees of both mental and physical impairment were present in 20% of patients. Vision was often hard to assess in demented patients but was associated with dependency in the non‐demented. Dependency was significantly related to age and self‐rated healthbut not to deafness and was related to mood disorder only in non‐demented patients nursed at home. Apart from this, these patients showed similar relations between dependency and physical and mental impairments to those living in institutions. Central nervous system disease was associated with greater dependency than other medical diagnoses. Preventative programmes, and effective management and treatment of the individual, will depend on careful diagnosis of the causes ofdependency.
Different influence of backward masking on visual pattern recognition in the early stages of presenile dementia and normal ageing
Authors: Müller Gottfried , Weisbrod Steffen , Klingberg Fritz 
Published: January 2005

AbstractThe effect of backward masking with illumination of all fields or with a checkerboard pattern, respectively, on the recognition of pattern + or T was measured on four groups of subjects: 21 presenile onset DAT patients, 16 patients with a questionable vascular dementia of the same age (CVD group), 15 age‐matched control subjects (EC group) and 16 younger control subjects (YC group, mean age 22 years). The pattern stimulus had a duration of 20 ms and was followed by the masking stimulus pattern (20 ms duration) with increasing intervals in steps of 5 ms. The mean recognition threshold (RT) for each of the four possible pattern–mask combinations was measured in five trials. The RTs decreased within the five trials in all groups. DAT patients and CVD patients adapted with different speeds during the five trials. We found a small significant RT difference between elder and younger control subjects, whereas patients had increased RTs in the first trial and differences in the four variants in the further trials compared with age‐matched controls. The test contributes to a set of data for diagnosis and differential diagnosis in the early stages of presenile dementia.
Comparison of zopiclone and flurazepam treatments in insomnia
Authors: Singh Amarendra N. , Bourgouin Jean 
Published: January 2005

AbstractIn this double‐blind study the efficacy and safety of two doses (7·5 and 11·25 mg) of zopiclone were compared to that of flurazepam (30 mg) in 60 insomniac patients divided into three groups. After an initial 4‐day washout period, placebo was administered single‐blind to all patients followed by 24 consecutive days of either one of the three drug levels. No significant difference was shown between the two zopiclone dosages at any time during the study for sleep efficacy and psychomotor performance. Compared to flurazepam, zopiclone was slightly less effective for sleep induction and sleep soundness variables. However, flurazepam was constantly worse than zopiclone for daytime performance. This study shows that both zopiclone dosages are shown to be active and safe in the treatment of insomnia, and exhibit a true advantage over flurazepam by its low incidence of residual effects.
Reported neurotoxicity with the lithium/haloperidol combination and other neuroleptics—A literature review
Authors: Batchelor D. H. , Lowe M. R. 
Published: January 2005

AbstractA literature review identified 33 case reports of neurotoxicity following combined treatment with lithium and haloperidol. The reports were assessed using criteria previously proposed as offering explanations for the clinical effects noted: lithium toxicity, uncertainties concerning the diagnoses and clinical management of some of the patients, and the probable involvement of the neuroleptic malignant syndrome.The presence of a true lithium/haloperidol interaction, or indeed any true interaction between lithium and neuroleptics, cannot readily be demonstrated from the data available. The combined use of lithium and haloperidol would appear to be relatively safe when serum lithium levels are maintained below 1·0 mmol/1.
Moclobemide pharmacokinetics in depressed patients: Lack of age effect
Authors: Maguire K. , Pereira A. , Tiller J. 
Published: January 2005

AbstractThe pharmacokinetics of moclobemide were examined in 19 depressed patients following a single oral dose of 50 mg. Ten patients were aged >60 years and nine <59 years. Plasma concentrations were analysed by gas chromatography with nitrogen‐specific detection. Pharmacokinetic parameters calculated were peak concentration, time to reach the peak, terminal disposition half‐life, area under the curve, oral clearance and apparent volume of distribution. No clinically significant differences were found betwen the two patient groups for these parameters. Thus there is no requirement for dosage adjustment in the older patient for moclobemide. This contrasts with some tricyclic and tetracyclic antidepressants which show significant age effects. Further studies of moclobemide for the treatment of elderly depression are warranted.
The effect of olfactory bulbectomy in the rat, alone or in combination with antidepressants and endogenous factors, on immune function
Authors: Song Cai , Leonard B. E. 
Published: January 2005

AbstractThe results from studies in the olfactory bulbectomized (OB) rat model of depression clearly show that the changes in the immune system following bulbectomy are similar to those reported in depressed patients. For example, mitogen‐stimulated lymphocyte proliferation and neutrophil phagocytosis are reduced while monocyte activity is elevated. In the differential white cell (WBC) count, the percentage of neutrophils is increased and the lymphocytes is decreased. In addition, an increase in some of positive acute phase proteins and a decrease in negative actue phase protein albumin are also found in OB rats.The antidepressants, such as serotonin reuptake inhibitors (fluvoxamine and sertraline), the antihistamine terfenadine, the cytokine IL‐2 and neuropeptide Y, which normalize both the brain noradrenergic and serotonergic system, attenuate the hyperactivity of OB rats in both the ‘open field’ and the open arms of the elevated plus‐maze, and reverse the suppression in both lymphocyte proliferation and neutrophil phagocytosis. Antidepressants (desipramine and lithium) which have been shown to normalize the noradrenergic and/or dopaminergic system in OB rats, significantly reverse the hyperactivity of OB rats in the ‘open field’ and the reduced neutrophil phagocytosis. However, most of these antidepressants and endogenous factors fail to normalize the abnormalities in the WBC count. Thymopeptide treatment normalizes the WBC count, the changes in the noradrenergic and serotonergic systems and lymphocyte proliferation but fails to attenuate the hyperactivity in OB rats. The action of thymopeptides on the immune system is direct, while antidepressants and other agents may indirectly affect the immune systems, via neurotransmitters and cytokines. The results from these studies also demonstrate the causal relationship between endogenous factors (such as the thymopeptides, NPY, IL‐2), the sigma ligand JO 1784 and depression.