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941.
942.
943.
Mustafa Murat Mutluay Serra Oğuz Dag Ørstavik Finn Fløystrand Arife Doğan Eva Söderling Timo Närhi Ingar Olsen 《Gerodontology》2010,27(4):283-291
doi:10.1111/j.1741‐2358.2009.00329.x Experiments on in vivo biofilm formation and in vitro adhesion of Candida species on polysiloxane liners Objectives: Microorganisms may colonise polysiloxane soft liners leading to bio‐deterioration. The aim of this study was to investigate in vitro adhesion and in vivo biofilm formation of Candida species on polysiloxane surfaces. Methods: The materials used in this study were Molloplast B, GC Reline soft, Mollosil Plus, Silagum Comfort and Palapress Vario. The in vitro retention of clinical isolates of Candida albicans to the relining and denture‐base materials by microscopic (scanning electron microscopy, SEM), conventional culturing methods and antimicrobial properties of these materials were studied. Candida found on materials and mucosa following long‐term use were identified and quantified, and biofilms covering the surfaces were investigated by SEM. Results: There was a significant decrease in the number of cells attached in vitro to saliva‐coated surfaces compared with non‐treated surfaces. An oral Candida carriage of 78% was found. Candida albicans, C. glabrata, C. intermedia and C. tropicalis were identified. In vivo biofilm formation on the liners appeared as massive colonisation by microorganisms. Conclusions: The results of the in vitro experiments suggest that salivary film influences early colonisation of different C. albicans strains. The film layer also minimises the differences among different strains. The Candida carriage of these patients was similar to denture‐wearing patients without soft liners. 相似文献
944.
Adrenal cells of newborn rat adrenals in primary tissue culture were treated with actinomycin D (2, 10 and 25 micrograms/ml), alpha-amanitin (5 and 50 micrograms/ml) and cordycepin (100 micrograms/ml) and studied with the electron microscope. The most striking changes observed with the three drugs were localized on the nucleoli, and consisted, respectively, of segregation (actinomycin D), fragmentation (alpha-amanitin) and microsegregation (cordycepin). These results are consistent with the molecular sites of action of the drugs and are comparable to previous in vivo findings. 相似文献
945.
Phorbol esters alter muscarinic receptor binding and inhibit polyphosphoinositide breakdown in human neuroblastoma (SH-SY5Y) cells 总被引:8,自引:0,他引:8
M Serra T L Smith H I Yamamura 《Biochemical and biophysical research communications》1986,140(1):160-166
Many recent reports have indicated that the effect of the phorbol ester tumor promoters is mediated through the Ca2+/phospholipid dependent protein kinase C. We have investigated the effect of two biologically active phorbol esters, 4 beta-phorbol 12 beta-myristate 13 alpha-acetate (PMA) and 4 beta-phorbol 12 beta,13 alpha-didecanoate (beta PDD) on muscarinic agonist binding and receptor-stimulated phosphoinositide breakdown in cultured human neuroblastoma (SH-SY5Y) cells. Preincubation of these cells with phorbol esters significantly reduced the carbachol-stimulated breakdown of inositol phospholipids and caused a decrease of agonist affinity for [3H](-)methyl quinuclidinyl benzilate ([3H](-)MQNB) binding without affecting the affinity of antagonist to the muscarinic receptor. The nontumor promoting 4 alpha-phorbol 12 beta,12 alpha-didecanoate (alpha PDD) was ineffective in our studies. These results suggest that the activation of protein kinase C may play an important role in regulating the muscarinic receptor system. 相似文献
946.
David Sebasti��n Maria Guitart Celia Garc��a-Mart��nez Caroline Mauvezin Josep M. Orellana-Gavald�� Dolors Serra Anna M. G��mez-Foix Fausto G. Hegardt Guillermina Asins 《Journal of lipid research》2009,50(9):1789-1799
Carnitine palmitoyltransferase 1 (CPT1) catalyzes the first step in long-chain fatty acid import into mitochondria, and it is believed to be rate limiting for β-oxidation of fatty acids. However, in muscle, other proteins may collaborate with CPT1. Fatty acid translocase/CD36 (FAT/CD36) may interact with CPT1 and contribute to fatty acid import into mitochondria in muscle. Here, we demonstrate that another membrane-bound fatty acid binding protein, fatty acid transport protein 1 (FATP1), collaborates with CPT1 for fatty acid import into mitochondria. Overexpression of FATP1 using adenovirus in L6E9 myotubes increased both fatty acid oxidation and palmitate esterification into triacylglycerides. Moreover, immunocytochemistry assays in transfected L6E9 myotubes showed that FATP1 was present in mitochondria and coimmunoprecipitated with CPT1 in L6E9 myotubes and rat skeletal muscle in vivo. The cooverexpression of FATP1 and CPT1 also enhanced mitochondrial fatty acid oxidation, similar to the cooverexpression of FAT/CD36 and CPT1. However, etomoxir, an irreversible inhibitor of CPT1, blocked all these effects. These data reveal that FATP1, like FAT/CD36, is associated with mitochondria and has a role in mitochondrial oxidation of fatty acids. 相似文献
947.
Serra PA Sciola L Delogu MR Spano A Monaco G Miele E Rocchitta G Miele M Migheli R Desole MS 《The Journal of biological chemistry》2002,277(37):34451-34461
Swiss mice were given 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), 25 mg/kg/day, for 5 consecutive days and killed at different days after MPTP discontinuance. Decreases in striatal tyrosine hydroxylase activity and levels of dopamine and its metabolites were observed 1 day after MPTP discontinuance. Ascorbic acid and glutamate levels had increased, dehydroascorbic acid and GSH decreased, whereas catabolites of high-energy phosphates (inosine, hypoxanthine, xanthine, and uric acid) were unchanged. In addition, gliosis was observed in both striatum and substantia nigra compacta (SNc). Sections of SNc showed some terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end labeling (TUNEL)-positive cells. Neurochemical parameters of dopaminergic activity showed a trend toward recovery 3 days after MPTP discontinuance. At this time point, TUNEL-positive cells were detected in SNc; some of them showed nuclei with neuronal morphology. A late (days 6-11) increase in striatal dopamine oxidative metabolism, ascorbic acid oxidative status, and catabolites of high-energy phosphates were observed concomitant with nigral neuron and nigrostriatal glial cell apoptotic death, as revealed by TUNEL, acridine orange, and Hoechst staining, and transmission electron microscopy. These data suggest that MPTP-induced activation/apoptotic death of glial cells plays a key role in the sequential linkage of neurochemical and cellular events leading to dopaminergic nigral neuron apoptotic death. 相似文献
948.
Sizing the radius of the pore formed in erythrocytes and lipid vesicles by the toxin sticholysin I from the sea anemone Stichodactyla helianthus 总被引:4,自引:0,他引:4
Tejuca M Dalla Serra M Potrich C Alvarez C Menestrina G 《The Journal of membrane biology》2001,183(2):125-135
Tamoxifen (tmx) is a non-steroidal triphenylethylene derivative that is predominantly known as a competitive antagonist at
the estrogen receptor and is used in the treatment of breast cancer. Recent studies suggest that tamoxifen is also beneficial
in the treatment of brain metastases and primary brain tumors. Tmx accumulates in brain and its concentration can be up to
46-fold higher than in serum. Therefore, astrocytes may be exposed to tmx in vivo.
We use the whole-cell patch-clamp technique to examine the effects of tmx on voltage-dependent cation currents in rat cortical
cultures. Using biophysical and pharmacological methods, we isolate sustained and transient outward potassium currents (I
KS
and I
KT
, respectively), inwardly rectifying potassium currents (I
KIR
), and transient inward sodium currents (I
Na
). We show that that TTX-sensitive I
Na
is completely inhibited by 10 μm tmx within 5 min. Similarly, tmx blocks I
KS
, but does not inhibit I
KT
or I
KIR
at these concentrations. Tmx effects are irreversible with 10 min wash.
Interestingly, the currents sensitive to tmx are important in growth control of glial cells (MacFarlane & Sontheimer, 1997).
Therefore, we examine cytotoxic and proliferative effects of tmx. Tmx (10 μm) is not cytotoxic as judged by trypan blue exclusion. However, incubation with tmx significantly reduces cell proliferation
as examined by 3[H]-thymidine uptake.
Received: 12 October 2000/Revised: 12 February 2001 相似文献
949.
950.