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C Paulin Y Charnay 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1992,314(6):259-262
The "delta sleep inducing peptide" (DSIP) is a regulatory peptide localized in the brain, the hypophysis and some endocrine cells of the gut. The present immunological study, performed with a monoclonal antibody to DSIP, provides evidence for the presence of DSIP-like immunoreactivity (DSIP-LI) in a strain of small cell carcinoma. The specificity of the immunoreaction was assessed by the tests using heterologous antigen known to be secreted by these cells. The DSIP could play a role in the course of this disease. 相似文献
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Marta Clariano Vanda Marques João Vaz Salma Awam Marta B. Afonso Maria Jesus Perry Cecília MP Rodrigues 《化学与生物多样性》2023,20(3):e202300222
Curcumin has a plethora of biological properties, making this compound potentially effective in the treatment of several diseases, including cancer. However, curcumin clinical use is compromised by its poor pharmacokinetics, being crucial to find novel analogs with better pharmacokinetic and pharmacological properties. Here, we aimed to evaluate the stability, bioavailability and pharmacokinetic profiles of monocarbonyl analogs of curcumin. A small library of monocarbonyl analogs of curcumin 1a–q was synthesized. Lipophilicity and stability in physiological conditions were both assessed by HPLC-UV, while two different methods assessed the electrophilic character of each compound monitored by NMR and by UV-spectroscopy. The potential therapeutic effect of the analogs 1a–q was evaluated in human colon carcinoma cells and toxicity in immortalized hepatocytes. Our results showed that the curcumin analog 1e is a promising agent against colorectal cancer, with improved stability and efficacy/safety profile. 相似文献
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Bacteriophage lambda and plasmid vectors, allowing fusion of cloned genes in each of the three translational phases. 总被引:3,自引:1,他引:2 下载免费PDF全文
We have constructed vectors from bacteriophage lambda and from plasmid pBR322 having a single EcoRI restriction site which is immediately downstream from the lac UV5 promotor. Each vector allows the fusion of a cloned gene to the lac Z gene in a different phase relative to the translation initiation codon of the lac Z gene. These vectors were constructed through modification of the initial EcoRI restriction site by S1 endonuclease treatment and then addition of octadeoxyribonucleotides (EcoRI linkers), which shifted the restriction site by 2 or 4 nucleotides. Used in combination these vectors should allow translation of a cloned gene in any one of the three coding phases. The bacteriophages vectors are certified as B2 (EK2) safety level vectors by the French "recombinaison génétique in vitro" committee (D.G.R.S.T.). 相似文献
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Robert Gramling Kathi L Heffner William MP Klein Laura E Zajac Mary Roberts Charles B Eaton 《BioPsychoSocial medicine》2010,4(1):11
Background
More optimistic perceptions of cardiovascular disease risk are associated with substantively lower rates of cardiovascular death among men. It remains unknown whether this association represents causality (i.e. perception leads to actions/conditions that influence cardiovascular disease occurrence) or residual confounding by unmeasured factors that associate with risk perceptions and with physiological processes that promote cardiovascular disease (i.e. inflammation or endothelial dysfunction). 相似文献8.
Iris M Costa Tallybia HT Nasser Marilene Demasi Rafaella MP Nascimento Luis ES Netto Sayuri Miyamoto Fernanda M Prado Gisele Monteiro 《BMC microbiology》2011,11(1):268
Background
The gene YCL047C, which has been renamed promoter of filamentation gene (POF1), has recently been described as a cell component involved in yeast filamentous growth. The objective of this work is to understand the molecular and biological function of this gene.Results
Here, we report that the protein encoded by the POF1 gene, Pof1p, is an ATPase that may be part of the Saccharomyces cerevisiae protein quality control pathway. According to the results, Δpof1 cells showed increased sensitivity to hydrogen peroxide, tert-butyl hydroperoxide, heat shock and protein unfolding agents, such as dithiothreitol and tunicamycin. Besides, the overexpression of POF1 suppressed the sensitivity of Δpct1, a strain that lacks a gene that encodes a phosphocholine cytidylyltransferase, to heat shock. In vitro analysis showed, however, that the purified Pof1p enzyme had no cytidylyltransferase activity but does have ATPase activity, with catalytic efficiency comparable to other ATPases involved in endoplasmic reticulum-associated degradation of proteins (ERAD). Supporting these findings, co-immunoprecipitation experiments showed a physical interaction between Pof1p and Ubc7p (an ubiquitin conjugating enzyme) in vivo.Conclusions
Taken together, the results strongly suggest that the biological function of Pof1p is related to the regulation of protein degradation.9.
The time of appearance and tissue concentrations of substance P-like immunoreactivity (SP-LI) were studied in 53 human fetuses aged 8-21 weeks. Detectable amounts were present at 8 weeks of gestation in available fragments of spinal cord and intestine. Thereafter, the tissue concentrations were highest in spinal cord, intermediate in hypothalamus and lowest in digestive tract. Except for a significant increase in the intestinal wall, the concentrations did not vary from the 8-14 to the 15-21 week period. At chromatography, SP-LI in extracts of spinal cord and intestine was essentially eluted in the volume of the synthetic undecapeptide. Using the indirect immunofluorescence technique, the localization of SP-LI positive structures in the digestive tract was studied in 5 fetuses aged 12-18 weeks. Scarce cell bodies were observed in the myenteric plexus. Nerve fibers were recognized in the muscular layer, in the myenteric plexus and in connective tissue of pancreas. The present results demonstrate the early appearance of SP-LI positive structures both in central nervous system and in the enteric nervous system in the human fetus. In the age range tested, SP-LI concentrations were noticeably higher in spinal cord and hypothalamus than in the digestive tract. 相似文献
10.
Sampling properties of DNA sequence data in phylogenetic analysis 总被引:20,自引:6,他引:20
We inferred phylogenetic trees from individual genes and random samples of
nucleotides from the mitochondrial genomes of 10 vertebrates and compared
the results to those obtained by analyzing the whole genomes. Individual
genes are poor samples in that they infrequently lead to the whole-genome
tree. A large number of nucleotide sites is needed to exactly determine the
whole-genome tree. A relatively small number of sites, however, often
results in a tree close to the whole-genome tree. We found that blocks of
contiguous sites were less likely to lead to the whole-genome tree than
samples composed of sites drawn individually from throughout the genome.
Samples of contiguous sites are not representative of the entire genome, a
condition that violates a basic assumption of the bootstrap method as it is
applied in phylogenetic studies.
相似文献