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131.
Small, gracile mostly tridactyl tracks from the Middle Jurassic of Henan Province represent the first example of the ichnogenus Anomoepus from this region. They represent a growing number of reports (at least eight) of this ichnogenus from the Jurassic of China. In conjunction with Changpeipus and Eubrontes, they appear characteristic of known global footprint biochrons. Anomoepus indicates the presence of ornithischian dinosaurs that are often scarce or unknown from skeletal remains in coeval deposits. When first discovered, these tracks were informally referred to as bird tracks. This interpretation reflects convergence between small Jurassic Anomoepus and avian theropod tracks that are hitherto known only from the Cretaceous and the Cenozoic. However, most Anomoepus are larger and more robust than any hitherto known Mesozoic avian tracks.  相似文献   
132.
BotIT6 is a neurotoxin polypeptide derived from the venom of the scorpion Buthus occitanus tunetanus (Bot). Its mature form is composed of 62 amino acids. BotIT6 has been reported to be the most potent toxin from Bot venom that has a strict selectivity for insects. Such toxin may have potential as a potent animal-harmless tool against insects. Using RT-PCR, we isolated and sequenced a cDNA encoding 62 amino acid residues corresponding to the known amino acid sequence of BotIT6. We have expressed a recombinant active form of BotIT6 in significantly high amounts in Escherichia coli. We have also engineered the cDNA into the Autographa californica Nuclear Polyhedrosis Virus (AcMNPV) genome and expressed the protein under control of the polyhedrin promoter. Supernatants of AcIT6-virus infected Sf9 insect cells exhibit a typical intoxication effect when injected to Spodoptera littoralis larvae. Moreover, injection of the recombinant virus showed enhanced insecticidal potency against S. littoralis larvae compared with wild type AcMNPV.  相似文献   
133.
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH, EC 1.2.1.12) was purified from two amphibian species, Xenopus laevis and Pleurodeles waltl. Comparative studies revealed that the two proteins differ by their subunit molecular masses, pI values and V8 digested peptide maps. The effect of zinc, cadmium and copper ions on GAPDH enzymatic activity has been examined in vitro. A time, metal concentration and metal type dependent inhibition was observed for both enzymes. X. laevis and P. waltl GAPDHs exhibit a much greater sensitivity to copper than to cadmium or zinc ions. Different half-lives and differential sensitivity to various metals was observed between the two enzymes with P. waltl GAPDH being remarkably tolerant to cadmium ions compared to the X. laevis enzyme. In order to understand the differential sensitivity of the two enzymes to metals, we produced 3D models of both X. laevis and P. waltl GAPDH structures based upon known 3D structures of GAPDHs from other species. This necessitated, in a first step, to clone a 900 bp cDNA fragment encoding the nearly full-length P. waltl GAPDH. Spatial motif searches on the homology models indicated potential metal binding sites involving cysteine and histidine residues outside the catalytic sites, existing only in either the X. laevis or the P. waltl GAPDH sequences.  相似文献   
134.
A prospective clinical parametric study comprising women afflicted by breast cancer and otherwise healthy participants was undertaken. The mean plasmatic concentration of putative leucine amino peptidase and nucleoside diphosphate phosphotransferase enzymatic complex in breast cancer cases was significantly elevated [43.9 +/- 2.8 microg ml(-1) (n = 9)] when compared to those found in otherwise healthy women [8.07 +/- 0.14 microg ml(-1) (n = 8)]. Women without images compatible with any tumours (n = 13) had a mean concentration of 10.77 +/- 1.49 microg ml(-1). The mean value obtained in women with fibroadenomas was 10.15 +/- 0.81 microg ml(-1) (n = 6) and with cystic fibrosis mastopathy 8.75 +/- 0.28 microg ml(-1) (n = 7). The efficacy of a tandem quantitative biodiagnostic system as a parametric screening tool for the early detection of breast cancer is underlined, raising the possibility of increasing the cost effectiveness of current imaging non-parametric technologies.  相似文献   
135.
Amongst the processes involved in the reverse cholesterol transport (RCT) from organs to liver, including high density lipoproteins-apolipoprotein AI (HDL-apoAI) dependent tissue uptake and cholesteryl ester transfer protein (CETP)-mediated transfers, the selective uptake of cholesteryl ester (CE) is of increasing interest through its antiatherogenic role. The purpose of this report is to develop a simple protocol allowing study of this process in an animal model with easier quantification of CE selective uptake. The dog was chosen essentially because this animal has a low CETP activity and an appropriate size to conduce a kinetic study. Tracer kinetics were performed to estimate in vivo the contributions of the pathways involved in HDL-CE turnover in dogs. Stable isotopes, 13C-acetate and D3-leucine as labeled precursors of CE and apoAI, were infused to fasting dogs. Isotopic enrichments were monitored in plasma unesterified cholesterol and in HDL-CE and apoAI by mass spectrometry. Kinetics were analyzed using compartmental modeling. Results concerned the measurement of the activity of cholesterol esterification (0.13±0.032 h−1), rate of HDL-apoAI catabolism (0.024±0.012 h−1), HDL-CE turnover (0.062±0.010 h−1) and CE selective uptake (0.038±0.014 h−1). Our results show that CE in dogs is mainly eliminated by selective uptake of HDL-CE (60% of HDL-CE turnover), unlike in other species studied by similar methods in our laboratory. This study shows that among species used to analyze cholesterol metabolism, the dog appears to be the animal in whom HDL-CE selective uptake represents the largest part of HDL-CE turnover.  相似文献   
136.
Chronic inflammation is a hallmark of several pathologies, such as rheumatoid arthritis, gastritis, inflammatory bowel disease, atherosclerosis and cancer. A wide range of anti-inflammatory chemicals have been used to treat such diseases while presenting high toxicity and numerous side effects. Here, we report the anti-inflammatory effect of a non-toxic, cost-effective natural agent, polyphenolic extract from the Tunisian quince Cydonia oblonga Miller. Lipopolysaccharide (LPS) treatment of human THP-1-derived macrophages induced the secretion of high levels of the pro-inflammatory cytokine TNF-α and the chemokine IL-8, which was inhibited by quince peel polyphenolic extract in a dose-dependent manner. Concomitantly, quince polyphenols enhanced the level of the anti-inflammatory cytokine IL-10 secreted by LPS-treated macrophages. We further demonstrated that the unexpected increase in IL-6 secretion that occurred when quince polyphenols were associated with LPS treatment was partially responsible for the polyphenols-mediated inhibition of TNF-α secretion. Biochemical analysis showed that quince polyphenols extract inhibited the LPS-mediated activation of three major cellular pro-inflammatory effectors, nuclear factor-kappa B (NF-κB), p38MAPK and Akt. Overall, our data indicate that quince peel polyphenolic extract induces a potent anti-inflammatory effect that may prove useful for the treatment of inflammatory diseases and that a quince-rich regimen may help to prevent and improve the treatment of such diseases.  相似文献   
137.
Many cellular processes depend on ERM (ezrin, moesin, and radixin) proteins mediating regulated linkage between plasma membrane and actin cytoskeleton. Although conformational activation of the ERM protein is mediated by the membrane PIP2, the known properties of the two described PIP2-binding sites do not explain activation. To elucidate the structural basis of possible mechanisms, we generated informative moesin mutations and tested three attributes: membrane localization of the expressed moesin, moesin binding to PIP2, and PIP2-induced release of moesin autoinhibition. The results demonstrate for the first time that the POCKET containing inositol 1,4,5-trisphosphate on crystal structure (the "POCKET" Lys-63, Lys-278 residues) mediates all three functions. Furthermore the second described PIP2-binding site (the "PATCH," Lys-253/Lys-254, Lys-262/Lys-263) is also essential for all three functions. In native autoinhibited ERM proteins, the POCKET is a cavity masked by an acidic linker, which we designate the "FLAP." Analysis of three mutant moesin constructs predicted to influence FLAP function demonstrated that the FLAP is a functional autoinhibitory region. Moreover, analysis of the cooperativity and stoichiometry demonstrate that the PATCH and POCKET do not bind PIP2 simultaneously. Based on our data and supporting published data, we propose a model of progressive activation of autoinhibited moesin by a single PIP2 molecule in the membrane. Initial transient binding of PIP2 to the PATCH initiates release of the FLAP, which enables transition of the same PIP2 molecule into the newly exposed POCKET where it binds stably and completes the conformational activation.  相似文献   
138.
The leaves and unripe and fully‐grown fruits of Schinus molle were collected from three geographical regions of Jordan: Amman (the Mediterranean), Madaba (Irano‐Turanean), and Sahab (Saharo‐Arabian). The hydrodistilled volatile oils of fresh and dried leaves and fruits were analyzed by gas chromatography‐mass spectrometry (GC/MS). The actual composition of the emitted volatiles was determined using Solid Phase Micro‐Extraction (SPME). α‐ and β‐Phellandrenes were the major components in all the analyzed samples. Quantitative differences were observed in the obtained essential oils (0.62–5.25 %). Additionally, cluster analysis was performed. Biologically, the antiproliferative activity of the essential oil, ethanol, and water extracts of the fruits and leaves was screened on Caco2, HCT116, MCF7, and T47D cell lines. The essential oil and ethanol extracts exhibited a dose‐dependent inhibition of cell growth with IC50 ranging between 21 and 65 μg/mL. The water extract did not exhibit any antiproliferative activity against the investigated cell lines.  相似文献   
139.

Background

Novel tuberculosis vaccines should be safe, immunogenic, and effective in various population groups, including HIV-infected individuals. In this phase II multi-centre, double-blind, placebo-controlled trial, the safety and immunogenicity of the novel H1/IC31 vaccine, a fusion protein of Ag85B-ESAT-6 (H1) formulated with the adjuvant IC31, was evaluated in HIV-infected adults.

Methods

HIV-infected adults with CD4+ T cell counts >350/mm3 and without evidence of active tuberculosis were enrolled and followed until day 182. H1/IC31 vaccine or placebo was randomly allocated in a 5∶1 ratio. The vaccine was administered intramuscularly at day 0 and 56. Safety assessment was based on medical history, clinical examinations, and blood and urine testing. Immunogenicity was determined by a short-term whole blood intracellular cytokine staining assay.

Results

47 of the 48 randomised participants completed both vaccinations. In total, 459 mild or moderate and 2 severe adverse events were reported. There were three serious adverse events in two vaccinees classified as not related to the investigational product. Local injection site reactions were more common in H1/IC31 versus placebo recipients (65.0% vs. 12.5%, p = 0.015). Solicited systemic and unsolicited adverse events were similar by study arm. The baseline CD4+ T cell count and HIV viral load were similar by study arm and remained constant over time. The H1/IC31 vaccine induced a persistent Th1-immune response with predominately TNF-α and IL-2 co-expressing CD4+ T cells, as well as polyfunctional IFN-γ, TNF-α and IL-2 expressing CD4+ T cells.

Conclusion

H1/IC31 was well tolerated and safe in HIV-infected adults with a CD4+ Lymphocyte count greater than 350 cells/mm3. The vaccine did not have an effect on CD4+ T cell count or HIV-1 viral load. H1/IC31 induced a specific and durable Th1 immune response.

Trial registration

Pan African Clinical Trials Registry (PACTR) PACTR201105000289276  相似文献   
140.
Nuclear lamins form the lamina on the interior surface of the nuclear envelope, and regulate nuclear metabolic events, including DNA replication and organization of chromatin. The current study is aimed at understanding the role of executioner caspase 6 on lamin A integrity in islet β-cells under duress of glucotoxic (20 mM glucose; 24 h) and diabetic conditions. Under glucotoxic conditions, glucose-stimulated insulin secretion and metabolic cell viability were significantly attenuated in INS-1 832/13 cells. Further, exposure of normal human islets, rat islets and INS-1 832/13 cells to glucotoxic conditions leads to caspase 6 activation and lamin A degradation, which is also observed in islets from the Zucker diabetic fatty rat, a model for type 2 diabetes (T2D), and in islets from a human donor with T2D. Z-Val-Glu-Ile-Asp-fluoromethylketone, a specific inhibitor of caspase 6, markedly attenuated high glucose-induced caspase 6 activation and lamin A degradation, confirming that caspase 6 mediates lamin A degradation under high glucose exposure conditions. Moreover, Z-Asp-Glu-Val-Asp-fluoromethylketone, a known caspase 3 inhibitor, significantly inhibited high glucose-induced caspase 6 activation and lamin A degradation, suggesting that activation of caspase 3 might be upstream to caspase 6 activation in the islet β-cell under glucotoxic conditions. Lastly, we report expression of ZMPSTE24, a zinc metallopeptidase involved in the processing of prelamin A to mature lamin A, in INS-1 832/13 cells and human islets; was unaffected by high glucose. We conclude that caspases 3 and 6 could contribute to alterations in the integrity of nuclear lamins leading to metabolic dysregulation and failure of the islet β-cell.  相似文献   
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