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1.
A retrovirus which encodes beta-galactosidase was used to infect embryonic rat striatal cells before grafting these cells into the lesioned adult rat striatum. Examination of the grafts after long term survival (8 months) revealed that a few small and large cells expressed large amounts of bacterial beta-galactosidase activity. The larger diameter cells were identified as neurones by their size, shape and presence of neuronal processes. The identity of the small diameter cell types was not established.  相似文献   

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According to the amyloid cascade hypothesis, sporadic Alzheimers disease (AD) is caused by the production and aggregation of -amyloid (A), and the production of A has recently been linked to the metabolism of cholesterol. We have previously published clinical studies where the effect of statin treatment on A production has been investigated. No effect on A was found, which is in disagreement with cell and animal studies. In the present study we investigated the effect of statin treatment on a disease-specific pattern consisting of a C-terminally-truncated quintet of A peptides. Nineteen patients with AD were treated with simvastatin for 12 months and the quintet of A peptides were analysed in cerebrospinal fluid before and after treatment. Also included was a group of 15 untreated patients with AD. We found that the A peptide pattern at baseline was in agreement with earlier findings; however, we did not find any change in the A peptide pattern after statin treatment. We suggest that clinical studies with extended treatment periods are performed where higher dosages of statins are used. We also believe that the pleiotropic effects of statins should be investigated further in order to elucidate the connection between Alzheimers disease and statin treatment.  相似文献   

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The expression of the 1 integrins was examined immunohistochemically in synoviocytes from normal synovial membrane and from chronic synovitis of different aetiology and intensity. Normal synoviocytes were 61-positive but lacked 1 through 5. In mild inflammation type A synoviocytes neo-expressed 1, 3, and 5 chains. In severe inflammation both type A and B synoviocytes expressed 3, 4, 5, and 6 chains. The effects of inflammatory cytokines, as single agents or in combination, on the 1 integrin expression in cultured normal synoviocytes was determined by immunocytochemistry and flow cytometry. The 1 chain, while absent in unstimulated synoviocytes, was induced by interleukin-1 (IL-1), tumour necrosis factor- (TNF-), and interferon- (INF-). This effect was enhanced by combining IL-1 and TNF-. Expression of the 3 chain was up-regulated by IL-1 and, more intensely, by IFN-. Transforming growth factor (TGF-) inhibited the up-regulating effect of IL-1 and antagonized the effect of IFN- on 3 chain expression. Expression of the 5 chain was up-regulated significantly by co-stimulation through IL-1 together with TGF- or TNF-. Thus, the 1 integrin profile of cytokine activated synoviocytes in vitro resembled that of synoviocytes in synovitis in situ. These data suggest that IL-1, TNF-, IFN-, and TGF- are likely to be among the effectors regulating 1 integrin expression in synoviocytes in vivo.  相似文献   

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An investigation of the cerebral circulation by the thermoelectric method showed that stimulation of the cervical sympathetic nerve leads to considerable changes in the blood supply to the brain. The changes in blood flow are biphasic in character: An initial small increase is followed by a decrease below the original level. Pharmacological analysis with and adrenoblockers showed that the constrictor response of the cerebral vessels is due to excitation of -adrenergic structures and the dilator response to excitation of -adrenergic structures. A possible mechanism of these changes is postulated.Laboratory of Pathophysiology of Respiration, Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. M. Chernukh). Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 1, pp. 9–12, January, 1976.  相似文献   

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Summary This communication describes conditions for Kluyveromyces lactis protoplast regeneration and transformation and shows that a high frequency of transformation can be obtained with recombinant plasmids containing one of a series of K. lactis DNA fragments that presumably carry autonomously replicating sequences (called KARS). The vector YRp7, which contains a Saccharomyces cerevisiae autonomously replicating sequence (ARS), only led to integrative transformation of K. lactis indicating substantial differences in specificity between the DNA replication mechanisms of both yeast species. It is further shown that 2-m DNA derived vectors giving high frequency transformation in S. cerevisiae can transform K. lactis only with low frequency.  相似文献   

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Research Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR G. N. Kryzhanovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 4, pp. 411–413, April, 1989.  相似文献   

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Summary Immunahistochemical double staining for gonadotropin releasing hormone (GnRH) and serotonin or dopamine--hydroxylase reveals close appositions of fibers which contain serotonin or norepinephrine to GnRH producing neurons in the septo-preoptic region. In the organum vasculosum of the lamina terminalis and in the median eminence extensive anatomical overlap exists in the distribution of GnRH and serotoninergic fibers but little of GnRH and noradrenalinergic fibers. It is proposed that serotonin plays a major role in the regulation of GnRH secretion via contacts in all of the regions studied and that the influence of norepinephrine on GnRH-secretion in the median eminence is exerted mainly via involvement of dopaminergic tuberoinfundibular neurons.Supported by the Deutsche Forschungs-Gemeinschaft Je 105/2, US PHS grant NS09914, and HD03110 to the Biological Sciences Research Center, Chapel Hill  相似文献   

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TGF- is thought to play a central role in pulmonary fibrosis inducing fibroblast differentiation and extracellular matrix synthesis. In human lung fibroblasts, it is still unclear how various TGB- isoforms affect TGF- production and whether glucocorticoids, commonly used agents to treat fibrotic lung disease, modulate these processes. To this end, human fetal lung fibroblasts (HFL-1) were cultured with various concentrations of glucocorticoids (budesonide, dexamethasone or hydrocortisone) with and without TFG-1, -2, and -3. TGF- mRNA was assessed by real time RT-PCR. Smad 2, 3, and 4 and AP-1 complex (c-fos and c-Jun) cellular localization were evaluated by immunostaining. TGF-2 and -3 stimulated TGF-1 production significantly (p < 0.01 relative to control). TGF-1 stimulated TGF-2 production (p < 0.01 relative to control). TGF-3 was undetectable. Glucocorticoids significantly inhibited TGF-1 and -2 production and reduced expression of the upregulated TGF-1 and -2 mRNA induced by exogenous TGF-1, -2 or -3 (p < 0.01 for each) but had no effect on Smads. Although c-jun-related nuclear staining was not intensified in TGF--stimulated cells, it was reduced by glucocorticoids. Thus, TGF- isoforms may stimulate production of various TGF- isoforms in the lung. Glucocorticoids then may block TGF- production by modulating mRNA levels and c-Jun.  相似文献   

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Laboratory of Membrane, Biochemistry, Institute of Applied Molecular Biology, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR S. E. Severin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 106, No. 9, pp. 319–321, September, 1988.  相似文献   

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Free radical oxidation of arachidonic acid with soybean lipoxygenase was accompanied by inhibition of retinal synthesis from -carotene catalyzed by enzyme preparation from rabbit intestinal mucosa. Lipoxygenase inhibitor salicylhydroxamic acid and antioxidants suppressing free radical reactions (ethyl gallate, -tocopherol, astaxanthine, and quercetin) promoted conversion of -carotene into retinal catalyzed by -carotene-15,15'-dioxygenase. These results indicate that lipoperoxides and/or products of their homolysis attenuate enzymatic conversion of -carotene and confirm the important role of natural antioxidants in the maintenance of stable vitamin A content in mammals.  相似文献   

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TGF- is thought to play a central role in pulmonary fibrosis inducing fibroblast differentiation and extracellular matrix synthesis. In human lung fibroblasts, it is still unclear how various TGF- isoforms affect TGF- production and whether glucocorticoids, commonly used agents to treat fibrotic lung disease, modulate these processes. To this end, human fetal lung fibroblasts (HFLF) were cultured with various concentrations of glucocorticoids (budesonide, dexamethasone or hydrocortisone) with and without TGF-1, -2, or -3. Post-culture media were collected for ELISA assays of TGF-1, -2, and -3 . TGF- mRNA was assessed by real time RT-PCR. Smad 2, 3, and 4 and AP-1 complex (c-fos and c-Jun) cellular localization were evaluated by immunostaining. TFG-2 and -3 stimulated TGF-1 production significantly (p < 0.01 relative to control). TGF-1 stimulated TGF-2 production (p < 0.01 relative to control). TGF-3 was undetectable. Glucocorticoids significantly inhibited TGF-1 and TGF-2 production and reduced expression of the up-regulated TGF-1 and TGF-2 mRNA induced by exogenous TGF-1, -2, or -3 (p < 0.01 for each) but had no effect on Smads. Although c-jun-related nuclear staining was not intensified in TGF--stimulated cells, it was reduced by glucocorticoids. Thus, TGF- isoforms may stimulate production of various TGF- isoforms in the lung. Glucocorticoids then may block TGF- production by modulating mRNA levels and c-Jun.  相似文献   

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