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1.
Elisa A. Waxman 《Biochemical and biophysical research communications》2010,391(3):1415-2639
α-Synuclein (α-syn) amyloid filaments are the major ultrastructural component of pathological inclusions that define several neurodegenerative disorders, including Parkinson disease and other disorders that are collectively termed synucleinopathies. Since the aggregation of α-syn is associated with the etiology of these diseases, defining the molecular elements that influence this process may have important therapeutics implication. The deletions of major portions of the hydrophobic region of α-syn (Δ74-79 and Δ71-82) impair the ability to form amyloid. However, mutating residue E83 to an A restored the ability of these proteins to form amyloid. Additionally supporting an inhibitory role of residue E83 on amyloid formation, mutating this residue to an A enhanced amyloid formation in the presence of small molecule inhibitors, such as dopamine and EGCG. Our data, therefore, suggest that the presence and placement of the highly charged E83 residue plays a significant inhibitory role in α-syn amyloid formation and these findings provide important insights in the planning of therapeutic agents that may be capable of preventing α-syn amyloid formation. 相似文献
2.
Keith G. Danielson Janice E. Knepper Frances S. Kittrell Janet S. Butel Daniel Medina Elisa M. Durban 《In vitro cellular & developmental biology. Plant》1989,25(6):535-543
Summary Clonal populations were isolated from the mouse mammary cell line, COMMA-D, by transfection with a dominant-selectable gene,
pSV2Neo, which confers resistance to the antibiotic, G418. Seven of twenty-four clones isolated retained the ability of the
parental line to repopulate cleared mammary fat pads in vivo as ductal-alveolar hyperplasias. Two sublines designated CDNR2
and CDNR4 retained hyperplastic growth potential after multiple passages in vitro with low incidence of tumor formation. A
third subpopulation, CDNR1, contained a single integration site for the pSV2Neo plasmid indicating a bonafide clonal origin
for this subline. CDNR1 cells displayed heterogeneous growth phenotypes in vivo including hyperplasia, adenocarcinoma, and
bone formation. Functional differentiation of CDNR1 cells organized as alveolarlike structures in vivo or on floating collagen
gels in vitro was observed as determined by immunoperoxidase staining for the milk-specific protein, casein. Overall, the
results indicate that a subset of cells from the COMMA-D cell line may be functionally analogous to stem cells existing in
the mammary gland.
Supported by NCI research grants CA-38650, CA-33369, CA-39017, and CA-25215. 相似文献
3.
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5.
A seven year follow-up of immune parameters is reported for a patient with chronic immune thrombocytopenic purpura (ITP) pre and post human immunodeficiency virus (HIV) seroconversion. Therapies such as intravenous IgG, prednisone, vincristine, or Ciclosporin A had no clear-cut beneficial effect on platelet counts. A long-term normalization of platelet counts was achieved by splenectomy. At splenectomy the patient was seropositive for HIV, most likely transmitted by blood products received half a year prior to laparatomy. Mean plasma levels of the second component of complement, C2, were half of the normal values prior to and within the lowest normal range post HIV seroconversion. Nevertheless, the T cell-dependent B cell response to HIV, which is dependent on the activation of C3 via the classical pathway of complement, was normal: Western blot analysis of total IgG and of IgG subclass responses to individual HIV antigens proved to be unimpaired. 相似文献
6.
Elisa Garcia Anja M. Hamers Hans E. N. Bergmans Bernard A. M. van der Zeijst Dr. Wim Gaastra 《Current microbiology》1988,17(6):333-337
Escherichia coli strains causing urinary tract infections in dogs produce fimbriae composed of fimbrial subunits closely related to the F12 and F13 fimbriae of human uropathogenic strains [4]. The adhesins carried by the fimbriae of human and canine isolates differ, however, as concluded from a different hemagglutination pattern and from the fact that the dog strains do not agglutinate latex beads coated with P-fimbriae receptor. This possible difference in adhesive specificity was confirmed by experiments in which the adhesion of human and dog isolates to dog kidney epithelial cells (MDCK cells) and human bladder epithelial cells (T24 cells) was compared. Dog uropathogenic strains, in contrast to human uropathogenicE. coli strains, adhere to MDCK cells but hardly to T24 cells. Adhesion to MDCK cells correlates with the presence of F12 or F13 fimbriae on the dog strains. These results suggest that homologous fimbrial subunits can carry different adhesin molecules and that these adhesin molecules can be responsible for species-specific adherence. On the contrary, adhesion of a number of dog uropathogenicProteus mirabilis strains to MDCK and T24 cells was not species specific; it depended on the mere presence of fimbriae. 相似文献
7.
The contribution deals with the phytocenological analysis of theRondeletio correifoliae-Andropogonetum multinervosi, an endemic savanna association occuring on the Siguanea Hills (Sierra de la Siguanea) near the Colony Hotel. 相似文献
8.
Mouse submandibular salivary epithelial cell growth and differentiation in long-term culture: Influence of the extracellular matrix 总被引:7,自引:0,他引:7
Elisa M. Durban 《In vitro cellular & developmental biology. Plant》1990,26(1):33-43
Summary The adult mouse submandibular salivary gland provides a good model system to study gene regulation during normal and abnormal
cell behavior because it synthesizes functionally distinct products ranging from growth factors and digestive enzymes to factors
of relevance to homeostatic mechanisms. The present study describes the long-term growth and differentiation of submandibular
salivary epithelial cells from adult male mice as a function of the culture substratum. Using a two-step partial dissociation
procedure, it was possible to enrich for ductal cells of the granular convoluted tubules, the site of epidermal growth factor
synthesis. Long-term cell growth over a period of 2 to 3 mo. with at least 3 serial passages was obtained only within three-dimensional
collagen gels. Cells grew as ductal-type structures, many of which generated lumens with time in culture. Electron microscopic
analysis in reference to the submandibular gland in vivo revealed enrichment for and maintenance of morphologic features of
granular convoluted tubule cells. Reactivity with a keratin-specific monoclonal antibody established the epithelial nature
of the cells that grew within collagen. Maintenance of cell differentiation, using immunoreactivity for epidermal growth factor
as criterion, was determined by both cytochemical and biochemical approaches and was found to be dependent on the collagen
matrix and hormones. Greater than 50% of the cells in primary collagen cultures contained epidermal growth factor only in
the presence of testosterone and triiodothyronine. In contrast, cells initially seeded on plastic or cycled to plastic from
collagen gels were virtually negative for epidermal growth factor. Biochemical analysis confirmed the presence of a protein
with an apparent molecular weight of 6000 which comigrated with purified mouse epidermal growth factor. Epidermal growth factor
was also present in detectable levels in Passage 1 cells. This culture system should permit assessment of whether modulation
of submandibular gland ductal cell growth can be exerted via a mechanism that in itself includes epidermal growth factor and
its receptor and signal transduction pathway.
This work was supported by Public Health Service grant DE07766 from the National Institute of Dental Research, National Institutes
of Health, Bethesda, MD. 相似文献
9.
Transfer of a marine DNA virus fromEctocarpus toFeldmannia (Ectocarpales,Phaeophyceae): aberrant symptoms and restitution of the host 总被引:1,自引:0,他引:1
Summary The marine brown algaEctocarpus siliculosus is invaded by a polyhedric virus, whose genome consists of circular, double-stranded DNA. In laboratory experiments this virus can infect a different host species,Feldmannia simplex. InfectedFeldmannia plants show severe somatic malformations. However, no functional virus particles are formed. SuchFeldmannia plants recover to resume a normal, symptom-free appearance. This result raises the possibility of intergeneric gene transfer in the natural habitat. 相似文献
10.
Elizabeth J. Fear Frida H. Torkelsen Elisa Zamboni Kuan-Ju Chen Martin Scott Glenn Jeffery Heidi Baseler Aneurin J. Kennerley 《Aging cell》2023,22(11):e14005
Mitochondrial function declines with age, and many pathological processes in neurodegenerative diseases stem from this dysfunction when mitochondria fail to produce the necessary energy required. Photobiomodulation (PBM), long-wavelength light therapy, has been shown to rescue mitochondrial function in animal models and improve human health, but clinical uptake is limited due to uncertainty around efficacy and the mechanisms responsible. Using 31P magnetisation transfer magnetic resonance spectroscopy (MT-MRS) we quantify, for the first time, the effects of 670 nm PBM treatment on healthy ageing human brains. We find a significant increase in the rate of ATP synthase flux in the brain after PBM in a cohort of older adults. Our study provides initial evidence of PBM therapeutic efficacy for improving mitochondrial function and restoring ATP flux with age, but recognises that wider studies are now required to confirm any resultant cognitive benefits. 相似文献