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排序方式: 共有3419条查询结果,搜索用时 15 毫秒
101.
Igor Bastos Polonio Milena Marques Pagliareli Acencio Rogério Pazetti Francine Maria de Almeida Bárbara Soares da Silva Karina Aparecida Bonifácio Pereira Rogério Souza 《Jornal brasileiro de pneumologia》2014,40(4):421-424
We assessed the effects of lodenafil on hemodynamics and inflammation in the rat
model of monocrotaline-induced pulmonary hypertension (PH). Thirty male
Sprague-Dawley rats were randomly divided into three groups: control; monocrotaline
(experimental model); and lodenafil (experimental model followed by lodenafil
treatment, p.o., 5 mg/kg daily for 28 days) Mean pulmonary artery pressure (mPAP) was
obtained by right heart catheterization. We investigated right ventricular
hypertrophy (RVH) and IL-1 levels in lung fragments. The number of cases of RVH was
significantly higher in the monocrotaline group than in the lodenafil and control
groups, as were mPAP and IL-1 levels. We conclude that lodenafil can prevent
monocrotaline-induced PH, RVH, and inflammation. 相似文献
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103.
African clawed frogs of the Xenopodinae (Xenopus+Silurana) constitute a well-defined system in which to study the evolutionary trajectory of duplicated genes and are a source of antimicrobial peptides with therapeutic potential. Allopolyploidization events within the Xenopodinae have given rise to tetraploid, octoploid, and dodecaploid species. The primary structures and distributions of host-defense peptides from the tetraploid frogs Xenopus borealis, Xenopus clivii, Xenopus laevis, Xenopus muelleri, "X. muelleri West", and Xenopus petersii may be compared with those from the octoploid frogs Xenopus amieti and X. andrei. Similarly, components in skin secretions from the diploid frog Silurana tropicalis may be compared with those from the tetraploid frog Silurana paratropicalis. All Xenopus antimicrobial peptides may be classified in the magainin, peptide glycine-leucine-amide (PGLa), caerulein-precursor fragment (CPF), and xenopsin-precursor fragment (XPF) families. However, the numbers of paralogs from the octoploid frogs were not significantly greater than the corresponding numbers from the tetraploid frogs. Magainins were not identified in skin secretions of Silurana frogs and the multiplicity of the PGLa, CPF, and XPF peptides from S. paratropicalis was not greater than that of S. tropicalis. The data indicate, therefore, that nonfunctionalization (gene silencing) has been the most common fate of antimicrobial peptide genes following polyploidization. While some duplicated gene products retain high antimicrobial potency (subfunctionalization), the very low activity of others suggests that they may be evolving towards a new biological role (neofunctionalization). CPF-AM1 and PGLa-AM1 from X. amieti show potential for development into anti-infective agents for use against antibiotic-resistant gram-negative bacteria. 相似文献
104.
105.
p63-microRNA feedback in keratinocyte senescence 总被引:1,自引:0,他引:1
Rivetti di Val Cervo P Lena AM Nicoloso M Rossi S Mancini M Zhou H Saintigny G Dellambra E Odorisio T Mahé C Calin GA Candi E Melino G 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(4):1133-1138
We investigated the expression of microRNAs (miRNAs) associated with replicative senescence in human primary keratinocytes. A cohort of miRNAs up-regulated in senescence was identified by genome-wide miRNA profiling, and their change in expression was validated in proliferative versus senescent cells. Among these, miRNA (miR)-138, -181a, -181b, and -130b expression increased with serial passages. miR-138, -181a, and -181b, but not miR-130b, overexpression in proliferating cells was sufficient per se to induce senescence, as evaluated by inhibition of BrdU incorporation and quantification of senescence-activated β-galactosidase staining. We identified Sirt1 as a direct target of miR-138, -181a, and -181b, whereas ΔNp63 expression was inhibited by miR-130b. We also found that ΔNp63α inhibits miR-138, -181a, -181b, and -130b expression by binding directly to p63-responsive elements located in close proximity to the genomic loci of these miRNAs in primary keratinocytes. These findings suggest that changes in miRNA expression, by modulating the levels of regulatory proteins such as p63 and Sirt1, strongly contribute to induction of senescence in primary human keratinocytes, thus linking these two proteins. Our data also indicate that suppression of miR-138, -181a, -181b, and -130b expression is part of a growth-promoting strategy of ΔNp63α in epidermal proliferating cells. 相似文献
106.
107.
108.
Miriam Coelho Molck Társis Paiva Vieira Ilária Cristina Sgardioli Milena Simioni Ana Paula dos Santos Josiane Souza Fabíola Paoli Monteiro Vera Lúcia Gil-da-Silva-Lopes 《European journal of medical genetics》2013,56(9):515-520
The 22q11.2 Deletion Syndrome (22q11.2DS) is the most common microdeletion syndrome in humans, with a highly variable phenotype. This chromosomal region contains low copy repeat (LCR) sequences that mediate non-allelic homologous recombination which predispose to copy number abnormalities at this locus. This article describes three patients investigated for suspicion of 22q11.2DS presenting atypical copy number abnormalities overlapping or not with the common ~3 Mb deletion. They were investigated by G-banding karyotype, Multiplex-ligation dependent probe amplification (MLPA) and array Genomic Hibridization (aGH). Clinical and molecular data were compared with literature, in order to contribute to genotype–phenotype correlation. Atypical chromosomal abnormalities were detected: 3.6 Mb deletion at 22q11.21-q11.23 between LCRs B–F in patient 1 and approximately 1.5 Mb deletion at 22q11.21-q11.22 between LCRs D–E in patients 2 and 3. The breakpoints detected in patient 1 have not been previously described. These findings exemplify the complexity and genetic heterogeneity observed in 22q11.2 region and corroborates the idea that genetic modifiers contribute to the phenotypic variability observed in proximal and distal 22q11.2 deletion syndromes. 相似文献
109.
110.
Ernil Hansen Milena Seemann Nina Zech Christian Doenitz Ralf Luerding Alexander Brawanski 《Acta neurochirurgica》2013,155(8):1417-1424