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Z. Srebro 《Cellular and molecular life sciences : CMLS》1966,22(12):847-849
Zusammenfassung Verletzungen des Endhirns beim erwachsenen Krallenfrosch (Xenopus laevis) führen zur Entstehung von Ventrikelteilen, die vollständig oder teilweise vom Ventrikelsystem des Gehirns isoliert sind. Das Ependym solcher Ventrikelteile zeigt stark Chromhämatoxylin-positive cytoplasmatische Einschlüsse (GPI), die im Perikaryon und in den Zellfortsätzen der Tanycyten lokalisiert sind. Charakter und Bedeutung der GPI werden diskutiert. 相似文献
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Summary We followed the kinetics of malonyldialdehyde in vivo and we found that it is very quickly metabolized. This may result in inaccuracy in the estimation of lipoperoxidation in the organism (reaction with 2-thiobarbituric acid). 相似文献
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Kuriakose MA Chen WT He ZM Sikora AG Zhang P Zhang ZY Qiu WL Hsu DF McMunn-Coffran C Brown SM Elango EM Delacure MD Chen FA 《Cellular and molecular life sciences : CMLS》2004,61(11):1372-1383
We applied a robust combinatorial (multi-test) approach to microarray data to identify genes consistently up- or down-regulated in head and neck squamous cell carcinoma (HNSCC). RNA was extracted from 22 paired samples of HNSCC and normal tissue from the same donors and hybridized to the Affymetrix U95A chip. Forty-two differentially expressed probe sets (representing 38 genes and one expressed sequence tag) satisfied all statistical tests of significance and were selected for further validation. Selected probe sets were validated by hierarchical clustering, multiple probe set concordance, and target-subunit agreement. In addition, real-time PCR analysis of 8 representative (randomly selected from 38) genes performed on both microarray-tested and independently obtained samples correlated well with the microarray data. The genes identified and validated by this method were in comparatively good agreement with other rigorous HNSCC microarray studies. From this study, we conclude that combinatorial analysis of microarray data is a promising technique for identifying differentially expressed genes with few false positives.Received 12 February 2004; received after revision 22 March 2004; accepted 14 April 2004 相似文献
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Wu RC Wang Z Liu MJ Chen DF Yue XS 《Cellular and molecular life sciences : CMLS》2004,61(16):2071-2082
In this study with cycloheximide (CHX, an inhibitor of protein synthesis) and the human leukaemic cell line U937, a novel form of chemoresistance, which we termed sudden drug resistance (SDR), was identified using Hoechst33258 staining, Western blott and DNA Ladder. CHXhigh (10–100 g/ml)-induced apoptosis can spontaneously subside after 4–6 h or can be inhibited by short-term preincubation with CHXlow (2.5 g/ml). Unlike typical multidrug resistance, SDR is not caused by reduced drug accumulation or altered protein expression, and may be associated with a non-P-glycoprotein mechanism. To uncover this underlying mechanism, we focused on U937 cell aggregation promoted by CHX, because cell adhesion has been suggested to influence cell survival and prevent apoptosis. EDTA, or anti-CD18 monoclonal antibody, but not EGTA, acetylsalicylic acid or RGDS tetrapeptide, abrogated this homotypic aggregation and greatly increased CHX-induced apoptosis in a time-dependent manner, while fibrinogen and soluble intercellular adhesion molecule-1 exerted opposite effects. These results establish that 2-integrin engagement is a key mediator of SDR, although it may be non-exclusive. This finding supplements the classical basis of chemoresistance and may provide another opportunity for improved leukemia therapy.Received 15 April 2004; received after revision 18 May 2004; accepted 21 June 2004 相似文献
999.
The cephalochordate amphioxus is the closest living invertebrate relative of the vertebrates. It is vertebrate-like in having a dorsal, hollow nerve cord, notochord, segmental muscles, pharyngeal gill slits and a post-anal tail that develops from a tail bud. However, amphioxus is less complex than vertebrates, lacking neural crest and having little or no mesenchyme. The genetic programs patterning the amphioxus embryo are also similar to those patterning vertebrate embryos, although the amphioxus genome lacks the extensive gene duplications characteristic of vertebrates. This relative structural and genomic simplicity in a vertebrate-like organism makes amphioxus ideal as a model organism for understanding mechanisms of vertebrate development.Received 18 February 2004; received after revision 9 April 2004; accepted 19 April 2004 相似文献
1000.
Zhong Z Kotova O Davidescu A Ehrén I Ekberg K Jörnvall H Wahren J Chibalin AV 《Cellular and molecular life sciences : CMLS》2004,61(21):2782-2790
Proinsulin-connecting peptide (C-peptide) exerts physiological effects partially via stimulation of Na+, K+-ATPase. We determined the molecular mechanism by which C-peptide stimulates Na+, K+-ATPase in primary human renal tubular cells (HRTCs). Incubation of the cells with 5 nM human C-peptide at 37°C for 10 min stimulated 86Rb+ uptake by 40% (p<0.01). The carboxy-terminal pentapeptide was found to elicit 57% of the activity of the intact molecule. In parallel with ouabain-sensitive 86Rb+ uptake, C-peptide increased subunit phosphorylation and basolateral membrane (BLM) abundance of the Na+, K+-ATPase 1 and 1 subunits. The increase in BLM abundance of the Na+, K+-ATPase 1 and 1 subunits was accompanied by depletion of 1 and 1 subunits from the endosomal compartments. C-peptide action on Na+, K+-ATPase was ERK1/2-dependent in HRTCs. C-peptide-stimulated Na+, K+-ATPase activation, phosphorylation of 1-subunit and translocation of 1 and 1 subunits to the BLM were abolished by a MEK1/2 inhibitor (20 M PD98059). C-peptide stimulation of 86Rb+ uptake was also abolished by preincubation of HRTCs with an inhibitor of PKC (1 M GF109203X). C-peptide stimulated phosphorylation of human Na+, K+-ATPase subunit on Thr-Pro amino acid motifs, which form specific ERK substrates. In conclusion, C-peptide stimulates sodium pump activity via ERK1/2-induced phosphorylation of Thr residues on the subunit of Na+, K+-ATPase.Received 15 June 2004; received after revision 14 September 2004; accepted 14 September 2004 相似文献