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101.
Castro-Obregón S Rao RV del Rio G Chen SF Poksay KS Rabizadeh S Vesce S Zhang XK Swanson RA Bredesen DE 《The Journal of biological chemistry》2004,279(17):17543-17553
Programmed cell death (pcd) may take the form of apoptosis or of nonapoptotic pcd. Whereas cysteine aspartyl-specific proteases (caspases) mediate apoptosis, the mediators of nonapoptotic cell death programs are much less well characterized. Here we report that alternative, nonapoptotic pcd induced by the neurokinin-1 receptor (NK(1)R) activated by its ligand Substance P, is mediated by a MAPK phosphorylation cascade recruited by the scaffold protein arrestin 2. The activation of the protein kinases Raf-1, MEK2, and ERK2 is essential for this form of nonapoptotic pcd, leading to the phosphorylation of the orphan nuclear receptor Nur77. NK(1)R-mediated cell death was inhibited by a dominant negative form of arrestin 2, Raf-1, or Nur77, by MEK1/2-specific inhibitors, and by RNA interference directed against ERK2 or MEK2 but not ERK1 or MEK1 and against Nur77. The MAPK pathway is also activated in neurons in primary culture undergoing NK(1)R-mediated death, since the MEK inhibitor PD98059 inhibited Substance P-induced death in primary striatal neurons. These results suggest that Nur77, which is regulated by a MAPK pathway activated via arrestin 2, modulates NK(1)R-mediated nonapoptotic pcd. 相似文献
102.
Gisel A Panetta M Grillo G Licciulli VF Liuni S Saccone C Pesole G 《Bioinformatics (Oxford, England)》2004,20(18):3676-3679
SUMMARY: DNAfan (DNA Feature ANalyzer) is a tool combining sequence-filtering and pattern searching. DNAfan automatically extracts user-defined sets of sequence fragments from large sequence sets. Fragments are defined by annotated gene feature keys and co- or non-occurring patterns within the feature or close to it. A gene feature parser and a pattern-based filter tool localizes and extracts the specific subset of sequences. The selected sequence data can subsequently be retrieved for analyses or further processed with DNAfan to find the occurrence of specific patterns or structural motifs. DNAfan is a powerful tool for pattern analysis. Its filter features restricts the pattern search to a well-defined set of sequences, allowing drastic reduction in false positive hits. AVAILABILITY: http://bighost.ba.itb.cnr.it:8080/Framework. 相似文献
103.
We have studied the hydrolytic degradation of high molecular weight poly(p-dioxanone), PPDX, sutures. The samples were degraded either in distilled water or in a phosphate buffer at 37 degrees C, and the starting viscosity-average molecular weight was 130 kg/mol. The hydrolytic degradation of PPDX occurs in an approximate two stage process where the amorphous regions of the sample are attacked faster than the crystalline regions of the sample. The changes experienced by the samples as degradation proceeded were successfully monitored by viscosimetry, differential scanning calorimetry (DSC), weight loss, pH changes, and scanning electron microscopy (SEM). Polarized optical microscopy (POM) observations performed on PPDX films revealed that PPDX crystallizes in spherulites whose detailed morphology depends on the supercooling employed during isothermal crystallization. Changes in the spherulitic morphology as molecular weight is reduced are only pronounced when the molecular weight is equal or lower than 8 kg/mol. The dependence of lamellar thickness as a function of isothermal crystallization temperature was examined by atomic force microscopy (AFM) in thin films of PPDX together with melting point data obtained by DSC. Through the use of the Thomson-Gibbs equation, we obtained a value of 166 erg/cm2 for the fold surface free energy of PPDX. This value is in the same range as those obtained previously for similar linear polyesters. The lamellar thickness, as well as the melting point, was found to have a small decreasing dependence with the molecular weight of the samples. 相似文献
104.
Rainaldi G Volpicella M Licciulli F Liuni S Gallerani R Ceci LR 《Nucleic acids research》2003,31(1):436-438
The updated version of PLMItRNA reports information and multialignments on 609 genes and 34 tRNA molecules active in the mitochondria of Viridiplantae (27 Embryophyta and 10 Chlorophyta), and photosynthetic algae (one Cryptophyta, four Rhodophyta and two Stramenopiles). Colour-code based tables reporting the different genetic origin of identified genes allow hyper-textual link to single entries. Promoter sequences identified for tRNA genes in the mitochondrial genomes of Angiospermae are also reported. The PLMItRNA database is accessible at http://bighost.area.ba.cnr.it/PLMItRNA/. 相似文献
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106.
Sucupira MC Sanabani S Cortes RM Giret MT Tomiyama H Sauer MM Sabino EC Janini LM Kallas EG Diaz RS 《PloS one》2012,7(1):e30292
Introduction
Primary HIV infection is usually caused by R5 viruses, and there is an association between the emergence of CCXR4-utilizing strains and faster disease progression. We characterized HIV-1 from a cohort of recently infected individuals in Brazil, predicted the virus''s co-receptor use based on the env genotype and attempted to correlate virus profiles with disease progression.Methods
A total of 72 recently infected HIV patients were recruited based on the Serologic Testing Algorithm for Recent HIV Seroconversion and were followed every three to four months for up to 78 weeks. The HIV-1 V3 region was characterized by sequencing nine to twelve weeks after enrollment. Disease progression was characterized by CD4+ T-cell count decline to levels consistently below 350 cells/µL.Results
Twelve out of 72 individuals (17%) were predicted to harbor CXCR4-utilizing strains; a baseline CD4<350 was more frequent among these individuals (p = 0.03). Fifty-seven individuals that were predicted to have CCR5-utilizing viruses and 10 individuals having CXCR4-utilizing strains presented with baseline CD4>350; after 78 weeks, 33 individuals with CCR5 strains and one individual with CXCR4 strains had CD4>350 (p = 0.001). There was no association between CD4 decline and demographic characteristics or HIV-1 subtype.Conclusions
Our findings confirm the presence of strains with higher in vitro pathogenicity during early HIV infection, suggesting that even among recently infected individuals, rapid progression may be a consequence of the early emergence of CXCR4-utilizing strains. Characterizing the HIV-1 V3 region by sequencing may be useful in predicting disease progression and guiding treatment initiation decisions. 相似文献107.
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110.
Identification of human immunodeficiency virus type 1 envelope genes recombinant between subtypes B and F in two epidemiologically linked individuals from Brazil. 总被引:15,自引:11,他引:4 下载免费PDF全文
E C Sabino E G Shpaer M G Morgado B T Korber R S Diaz V Bongertz S Cavalcante B Galvo-Castro J I Mullins A Mayer 《Journal of virology》1994,68(10):6340-6346
Sequence analysis of a human immunodeficiency virus type 1 env gene PCR amplified from a Brazilian woman's peripheral blood mononuclear cell DNA (sample RJIO1) showed that it was likely to have been derived from a double recombination event between human immunodeficiency virus type 1 subtypes B and F. The major portion of the gp120 coding sequence belonged to the B lineage, but a segment of the C2 to V3 region (approximately 135 nucleotides) clearly associated with sequences of the F lineage. The subtype F-like segment had 15 noncontiguous signature nucleotides in common with Brazilian subtype F sequences that were not found, or were rare, in subtype B sequences. In contrast, this same segment had only 3 signature nucleotides shared with subtype B sequences and not present in the Brazilian subtype F sequences. Phylogenetic analysis, amino acid signature pattern analysis, and the pattern of synonymous mutations all supported the hypothesis of a recombinational origin of the RJIO1 sequence. Related recombinant genes were also detected in peripheral blood mononuclear cell DNA obtained from the woman's recent sexual partner, indicating that the recombination event probably occurred at some previous time in the chain of virus transmission. Divergent viral sequences in the V3 region were found in the male sexual partner, while a relatively homogeneous viral population was detected in the woman, consistent with her recent infection. 相似文献