instruction:
In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.
question:
Lipid rafts are micro-domains of ordered lipids (L o phase) in biological membranes. The L o phase of cellular membranes can be isolated from disordered lipids (L d phase) after treatment with 1 % Triton X-100 at 4°C in which the L o phase forms the detergent-resistant membrane (DRM) fraction. The lipid composition of DRM derived from Madin-Darby canine kidney (MDCK) cells, McArdle cells and porcine sperm is compared with that of the whole cell. Remarkably, the unsaturation and chain length degree of aliphatic chains attached to phospholipids is virtually the same between DRM and whole cells. Cholesterol and sphingomyelin were enriched in DRMs but to a cell-specific molar ratio. Sulfatides (sphingolipids from MDCK cells) were enriched in the DRM while a seminolipid (an alkylacylglycerolipid from sperm) was depleted from the DRM. Treatment with<5 mM methyl-ß-cyclodextrin (MBCD) caused cholesterol removal from the DRM without affecting the composition and amount of the phospholipid while higher levels disrupted the DRM. The substantial amount of (poly)unsaturated phospholipids in DRMs as well as a low stoichiometric amount of cholesterol suggest that lipid rafts in biological membranes are more fluid and dynamic than previously anticipated. Using negative staining, ultrastructural features of DRM were monitored and in all three cell types the DRMs appeared as multilamellar vesicular structures with a similar morphology. The detergent resistance is a result of protein-cholesterol and sphingolipid interactions allowing a relatively passive attraction of phospholipids to maintain the L o phase. For this special issue, the relevance of our findings is discussed in a sperm physiological context.
answer:
Ultrastructure and lipid composition of detergent-resistant membranes derived from mammalian sperm and two types of epithelial cells


question:
This article employs a state-of-the-art panel threshold model by allowing for regime intercepts, in order to shed new light on the asymmetric/ nonlinear effects of local and global sentiments on expected industry stock returns among 11 Asian countries during the period from 1996 to 2010. Empirical evidence demonstrates that once the regime intercept is included, the asymmetric effects of global sentiment on oil & gas, financials, and health care industry returns become less under optimism, as compared with under pessimism. More critically, the positive (negative) impact of global sentiment above (under) the threshold turns significant, indicating that global optimism leads industry returns to be overvalued, while pessimism leads them to be undervalued. For local market sentiment, our results support that higher local sentiment enhances the returns of basic materials, telecommunications, and utilities industries. The empirical results confirm that the nexus of industry returns and investor sentiments is subject to change between different sentimental intervals.
answer:
Asymmetric effects of investor sentiment on industry stock returns: Panel data evidence


question:
YopH is a bacterial protein tyrosine phosphatase, which is essential for the viability and pathogenic virulence of the plague-causing Yersinia sp. bacteria. Inactivation of YopH activity would lead to the loss of bacterial pathogenicity. We have studied the inhibitory properties of aurintricarboxylic acid (ATA) against YopH phosphatase and found that at nanomolar concentrations ATA reversibly decreases the activity of YopH. Computational docking studies indicated that in all binding poses ATA binds in the YopH active site. Molecular dynamics simulations showed that in the predicted binding pose, ATA binds to the essential Cys403 and Arg409 residues in the active site and has a stronger binding affinity than the natural substrate (pTyr). The cyclic voltammetry experiments suggest that ATA reacts remarkably strongly with molecular oxygen. Additionally, the electrochemical reduction of ATA in the presence of a negative potential from -2.0 to 2.5 V generates a current signal, which is observed for hydrogen peroxide. Here we showed that ATA indicates a unique mechanism of YopH inactivation due to a redox process. We proposed that the potent inhibitory properties of ATA are a result of its strong binding in the YopH active site and in situ generation of hydrogen peroxide near catalytic cysteine residue.
answer:

Redox process is crucial for inhibitory properties of aurintricarboxylic acid against activity of YopH: virulence factor of Yersinia pestis