| 4. |
- Popova, Svetlana N., et al.
(författare)
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The mesenchymal alpha 11 beta 1 integrin attenuates PDGF-BB-stimulated chemotaxis of embryonic fibroblasts on collagens
- 2004
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Ingår i: DEVELOPMENTAL BIOLOGY. - 0012-1606. ; 270:2, s. 427-442
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Tidskriftsartikel (refereegranskat)abstract
- α11β1 constitutes the most recent addition to the integrin family and has been shown to display a binding preference for interstitial collagens found in mesenchymal tissues. We have previously observed that when α11β1 integrin is expressed in cells lacking endogenous collagen receptors, it can mediate PDGF-BB-dependent chemotaxis on collagen I in vitro. To determine in which cells PDGF and α11β1 might cooperate in regulating cell migration in vivo, we studied in detail the expression and distribution of α11 integrin chain in mouse embryos and tested the ability of PDGF isoforms to stimulate the α11β1-mediated cell migration of embryonic fibroblasts. Full-length mouse α11 cDNA was sequenced and antibodies were raised to deduced α11 integrin amino acid sequence. In the embryonic mouse head, α11 protein and RNA were localized to ectomesenchymally derived cells. In the periodontal ligament, α11β1 was expressed as the only detectable collagen-binding integrin, and α11β1 is thus a major receptor for cell migration and matrix organization in this cell population. In the remainder of the embryo, the α11 chain was expressed in a subset of mesenchymal cells including tendon/ligament fibroblasts, perichondrial cells, and intestinal villi fibroblasts. Most of the α11-expressing cells also expressed the α2 integrin chain, but no detectable overlap was found with the α1 integrin chain. In cells expressing multiple collagen receptors, these might function to promote a more stable cell adhesion and render the cells more resistant to chemotactic stimuli. Wild-type embryonic fibroblasts activated mainly the PDGF β receptor in response to PDGF-BB and migrated on collagens I, II, III, IV, V, and XI in response to PDGF-BB in vitro, whereas mutant fibroblasts that lacked α11β1 in their collagen receptor repertoire showed a stronger chemotactic response on collagens when stimulated with PDGF-BB. In the cellular context of embryonic fibroblasts, α11β1 is thus anti-migratory. We speculate that the PDGF BB-dependent cell migration of mesenchymal cells is tightly regulated by the collagen receptor repertoire, and disturbances of this repertoire might lead to unregulated cell migration that could affect normal embryonic development and tissue structure. Keywords: α11β1 integrin; Immunohistochemistry; In situ hybridization; Mouse embryogenesis; Cell migration
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| 5. |
- Román, Gustavo C, et al.
(författare)
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Vascular cognitive disorder: a new diagnostic category updating vascular cognitive impairment and vascular dementia.
- 2004
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Ingår i: Journal of the neurological sciences. - : Elsevier BV. - 0022-510X. ; 226:1-2, s. 81-7
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Forskningsöversikt (refereegranskat)abstract
- Vascular cognitive impairment (VCI) was proposed as an umbrella term to include subjects affected with any degree of cognitive impairment resulting from cerebrovascular disease (CVD), ranging from mild cognitive impairment (MCI) to vascular dementia. VCI may or may not exclude the host of "focal" circumscribed impairments of specialized functions such as language (aphasia), intentional gesture (apraxia), or categorical recognition (agnosia), among others, that may result from a stroke. Therefore, there are no universally accepted diagnostic criteria for VCI. We conclude that this concept could be more useful if it were to be limited to cases of vascular MCI without dementia, by analogy with the concept of amnestic MCI, currently considered the earliest clinically diagnosable stage of Alzheimer disease (AD). In agreement with our view,the Canadian Study on Health and Aging successfully implemented a restricted definition of VCI, excluding cases of dementia (i.e., vascular cognitive impairment no dementia, VCI-ND). The Canadian definition and diagnostic criteria could be utilized for future studies of VCI. This definition excludes isolated impairments of specialized cognitive functions.Vascular dementia (VaD): The main problem of this diagnostic category stems from the currently accepted definition of dementia that requires memory loss as the sine qua non for the diagnosis. This may result in over-sampling of patients with AD worsened by stroke (AD+CVD). This problem was minimized in controlled clinical trials of VaD by excluding patients with a prior diagnosis of AD, those with pre-existing memory loss before the index stroke, and those with amnestic MCI. We propose a definition of dementia in VaD based on presence of abnormal executive control function, severe enough to interfere with social or occupational functioning. Vascular cognitive disorder (VCD): This term, proposed by Sachdev [P. Sachdev, Vascular cognitive disorder. Int J Geriat Psychiatry 14 (1999)402-403.] would become the global diagnostic category for cognitive impairment of vascular origin, ranging from VCI to VaD. It would include specific disease entities such as post-stroke VCI, post-stroke VaD, CADASIL, Binswanger disease, and AD plus CVD. This category explicitly excludes isolated cognitive dysfunctions such as those mentioned above.
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| 6. |
- Wensbo, David, et al.
(författare)
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Preparation of five-membered heterocyclic compounds as mGluR5 receptor antagonists.
- 2004
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Patent (populärvet., debatt m.m.)abstract
- The present invention relates to five-membered heterocyclic compds. (shown as I; variables defined below; e.g. II), a process for their prepn. and new intermediates prepd. therein, pharmaceutical formulations contg. said compds. and to the use of said compds. in therapy, e.g. neurol., psychiatric and chronic and acute pain disorders (no data). Typical IC50 values for mGluR5 receptor antagonist activity are ≤10 μM; no values for individual compds. are given. Methods of prepn. are claimed and example prepns. and/or characterization data are included for ∼800 examples of I and intermediates. For example, [3-[3-[[[4-methyl-5-(thiophen-2-yl)-4H-[1,2,4]triazol-3-yl]sulfanyl]methyl][1,2,4]oxadiazol-5-yl]phenyl]carbamic acid tert-Bu ester was prepd. in 79% yield by condensation of 4-methyl-5-(thiophen-2-yl)-4H-[1,2,4]triazole-3-thiol with [3-(3-chloromethyl-[1,2,4]oxadiazol-5-yl)phenyl]carbamic acid tert-Bu ester in MeCN in the presence of K2CO3. For I: P = H, C3-7alkyl or a 3- to 8-membered ring contg. ≥1 atoms = C, N, O and S, which ring may optionally be fused with a 5- or 6-membered ring contg. ≥1 C, N, O and S; R1 = H, hydroxy, halo, nitro, C1-6-alkylhalo, OC1-6alkylhalo, C1-6alkyl, OC1-6alkyl, C2-6alkenyl, OC2-6alkenyl, C2-6alkynyl, OC2-6alkynyl, C0-6alkylC3-6cycloalkyl, etc. and a 5- or 6-membered ring contg. ≥1 C, N, O and S, wherein said ring may be substituted by ≥1 A. M1 = a bond, C1-3alkyl, C2-3alkenyl, C2-3alkynyl, C0-4alkyl(CO)C0-4alkyl, C0-3alkylOC0-3alkyl, C0-3alkyl(CO)NR5, C0-3alkyl(CO)NR5C0-3alkyl, C0-4-alkylNR5, C0-3alkylSC0-3alkyl, etc.; R2 = H, hydroxy, C0-6alkylcyano, oxo, NR5, NOR5, C1-4alkylhalo, halo, C1-4alkyl, etc. X1, X2 and X3 = CR, CO, N, NR, O and S; R = H, C0-3alkyl, halo, C0-3alkylOR5, C0-3-alkylNR5R6, C0-3alkyl(CO)OR5, C0-3alkylNR5R6 and C0-3alkylaryl; M2 = a bond, C1-3alkyl, C3-7cycloalkyl, C2-3alkenyl, C2-3alkynyl, C0-4alkyl(CO)C0-4alkyl, C0-3alkylOC0-3alkyl, etc.; R3 = H, hydroxy, C0-6alkylcyano, oxo, NR, NOR5, C1-4alkylhalo, halo, C1-4alkyl, etc. X4 = C0-4alkylR5, C0-4alkyl(NR5R6), C0-4-alkyl(NR5R6):N, NR5C0-4alkyl(NR5R6):N, NOC0-4alkyl, C1-4alkylhalo, C, O, SO, SO2 and S; Q is a 5- or 6-membered ring contg. ≥1 C, N, O and S, which group may optionally be fused with a 5- or 6-membered ring contg. ≥1 C, N, O and S and which fused ring may be substituted by ≥1 A. R4 = H, hydroxy, C0-6alkylcyano, oxo, NR5, NOR5, C1-4alkylhalo, halo, C1-4alkyl, OC1-4alkyl, OC0-6alkylaryl, etc. and a 5- or 6-membered ring contg. ≥1 atoms = C, N, O or S, wherein said ring may be substituted by ≥1 A; R5, R6 = H, OH, C1-6alkyl, etc.; A = H, OH, O, halo, nitro, C0-6alkylcyano, etc.; m = 0-4; and n = 0-3; addnl. details are given in the claims. [on SciFinder(R)]
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