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Delay tolerant networks are resource-constrained networks, where nodes are required to cooperate with each other to relay messages (bundles) in a store-carry-forward fashion. Because of the constrained resources, some selfish nodes are reluctant to relay bundles for other nodes in order to save their own resources. Previous studies focus on one kind of creditbased incentive schemes in which a source pays credits (virtual coins) to intermediates to compensate for their resources consumption. Although these schemes can restrain selfish behaviors to a certain extent, they may cause an undesirable effect on some honest nodes, especially on boundary nodes and inactive nodes. To mitigate this issue, first we propose a service priority-based incentive scheme (SIS) where a relaying (viewed as a service) priority, instead of credits, is used as an incentive metric to stimulate nodes to fairly cooperate. In the SIS, a node which relayed more bundles is granted a higher service priority, and it will obtain a higher bundle delivery ratio correspondingly. Then, to deal with the potential attacks against the SIS, we also present three security solutions including the signature chain, cooperation frequency statistics, and combination clearance. We evaluate the proposed scheme on the opportunistic network environment simulator. The extensive results show that the SIS is able to improve the bundle delivery ratio of honest nodes and efficiently inhibits the selfish behaviors in comparison with credit-based incentive schemes. [ABSTRACT FROM AUTHOR]

Background: Proteomic approaches based on mass spectrometry have been recently used in archaeological and art researches, generating promising results for protein identification. Little information is known about eastward spread and eastern limits of prehistoric milking in eastern Eurasia. Methodology/Principal Finding: In this paper, an ancient visible food remain from Subeixi Cemeteries (cal. 500 to 300 years BC) of the Turpan Basin in Xinjiang, China, preliminarily determined containing 0.432 mg/kg cattle casein with ELISA, was analyzed by using an improved method based on liquid chromatography (LC) coupled with MALDI-TOF/TOF-MS to further identify protein origin. The specific sequence of bovine casein and the homology sequence of goat/sheep casein were identified. Conclusions/Significance: The existence of milk component in ancient food implies goat/sheep and cattle milking in ancient Subeixi region, the furthest eastern location of prehistoric milking in the Old World up to date. It is envisioned that this work provides a new approach for ancient residue analysis and other archaeometry field. [ABSTRACT FROM AUTHOR]

Different glycoforms of some proteins have been identified as differential spots for certain diseases in 2-DE, indicating disease-related glycosylation changes. It is routine to determine the site-specific glycosylation of nonsialylated N-glycoproteins from a single gel spot, but some obstacles still exist in analyzing sialylated glycoproteins due to the lability and higher detection limit of acid glycans in MALDI-TOF/TOF analysis. Thus, we present an improved protocol here. Tryptic glycopeptides were separated and subjected to MALDI-TOF/TOF analysis, resulting in the identification of site-specific glycosylation of high-intensity glycopeptides. Sequential deglycosylation and desialylation were used to improve the identification of glycosylation sites and desialylated glycans. The site-specific glycosylation of large glycopeptides and lowintensity glycopeptides was deduced based on the masses of glycopeptides, deglycosylated peptides and desialylated glycans. By applying it to 2-DE separated human serum, the difference of N-glycosylation was successfully determined for α1-antitrypsin between different gel spots. [ABSTRACT FROM AUTHOR]

Lymph node involvement is the most important predictor of survival rates in patients with oral squamous cell carcinoma (OSCC). A biomarker that can indicate lymph node metastasis would be valuable to classify patients with OSCC for optimal treatment. In this study, we have performed a serum proteomic analysis of OSCC using 2-D gel electrophoresis and liquid chromatography/tandem mass spectrometry. One of the down-regulated proteins in OSCC was identified as tetranectin, which is a protein encoded by the CLEC3B gene (C-type lectin domain family 3, member B). We further tested the protein level in serum and saliva from patients with lymph-node metastatic and primary OSCC. Tetranectin was found significantly under-expressed in both serum and saliva of metastatic OSCC compared to primary OSCC. Our results suggest that serum or saliva tetranectin may serve as a potential biomarker for metastatic OSCC. Other candidate serum biomarkers for OSCC included superoxide dismutase, ficolin 2, CD-5 antigen-like protein, RalA binding protein 1, plasma retinol-binding protein and transthyretin. Their clinical utility for OSCC detection remains to be further tested in cancer patients. [ABSTRACT FROM AUTHOR]

Introduction Glycosyiation is an important component for a number of biological processes and is perhaps the most abundant and comphcated of the known post-translational modifications found on proteins. Methods This work combines two-dimensional (2-D) polyacrylamide gel electrbphoresis and lectin blotting to map the salivary glycome and mass spectrometry to identity the proteins that are associated with the glycome map. A panel of 15 lectins that recognize six sugar-specific categories was used to visualize the type and extent ofglycosylation in saliva from two healthy male individuals. Lectin blots were compared to 2-D gels stained either with Sypro Ruby (protein stain) or Pro-Q Emerald 488 (glycoprotein stain). Results Each lectin shows a distinct pattern, even those belonging to the same sugar-specific category. In addition, the glycosylation profiles generated from the lectin blots show that most salivary proteins are glycosylated and that the profiles are more widespread than is demonstrated by the glycoprotein-stained gel. Finally, the coreactivity between lectins was measured to determine what types of glycan structures are associated with one another and also the population variation of the lectin reactivity for 66 individuals were reported. Conclusions This starting 2-D gel glycosylation reference map shows that the scientifically accepted, individual oligosaccharide variability is not limited to a few large glycoproteins such as MUC5B, but are found on most members of the salivary proteome. Finally, in order to see the full range of oligosaccharide distribution, multiple reagents or lectins are needed. [ABSTRACT FROM AUTHOR]

The article focuses on a study which aims to determine protein and messenger RNA (mRNA) biomarkers in human whole saliva (WS) that may be used in detecting primary Sjögren's syndrome (SS). It cites the use of mass spectrometry and expression microarray profiling to identify candidate protein and mRNA biomarkers of primary SS in WS samples. The results indicated that WS from patients with primary SS contains molecular signatures that reflect damaged glandular cells and an activated immune response in such disease.

The success of targeting kinases in cancer with small molecule inhibitors has been tempered by the emergence of drug-resistant kinase domain mutations. In patients with chronic myeloid leukemia treated with ABL inhibitors, BCR-ABL kinase domain mutations are the principal mechanism of relapse. Certain mutations are occasionally detected before treatment, suggesting increased fitness relative to wild-type p210 BCR-ABL. We evaluated the oncogenicity of eight kinase inhibitor-resistant BCR-ABL mutants and found a spectrum of potencies greater or less than p210. Although most fitness alterations correlate with changes in kinase activity, this is not the case with the T315l BCR-ABL mutation that confers clinical resistance to all currently approved ABL kinase inhibitors. Through global phosphoproteome analysis, we identified a unique phosphosubstrate signature associated with each drug-resistant allele, including a shift in phosphorylation of two tyrosines (Tyr253 and Tyr257) in the ATP binding loop (P-loop) of BCR-ABL when Thr315 is Ile or Ala. Mutational analysis of these tyrosines in the context of Thr315 mutations demonstrates that the identity of the gatekeeper residue impacts oncogenicity by altered P-loop phosphorylation. Therefore, mutations that confer clinical resistance to kinase inhibitors can substantially alter kinase function and confer novel biological properties that may impact disease progression. [ABSTRACT FROM AUTHOR]

In this paper, we present our application of latest information technology in assisting the Chinese acupuncture research. Having integrated the Chinese Visible Human (CVH) data, virtual reality, visualization and imaging techniques, we have constructed a 3-dimensional digital human model for acupuncture. This model integrates the meridian positioning, acupoint positioning, arbitrary cutting-plane visualization, multi-layer dissection, needle puncturing simulation, as well as the common diseases-therapy information. Our work can be widely applied to Chinese acupuncture education, clinical usage and scientific research. [ABSTRACT FROM AUTHOR]

The bacterial actin homolog, MreB, forms helical cables within the cell that are required for maintenance of a rod shape. These helical structures are thought to be involved in the spatial organization of cell wall (peptidoglycan) synthesizing complexes of penicillin- binding proteins (PBPs). Here, we examined the role of the MreC cell shape protein in this process in Caulobacter crescentus. Sub-cellular fractionation experiments showed that MreC is a periplasmic protein and, as assayed by immunofluorescence microscopy, adopted helical or banded patterns along the cell length reminiscent of those formed by MreB and PBP2. The pattern of MreC and PBP2 localization remained when MreB cables were disrupted by treatment with the inhibitor A22. However, long-term absence of MreB led to cell shape changes and an eventual loss of MreC localization, suggesting that an independent structure, perhaps an intact peptidoglycan layer, contributes to the MreC localization pattern. Using affinity chromatography with MreC covalently bound to Sepharose, we isolated several PBPs from cell extracts that eluted from the column as heterogeneous complexes. In this same experiment, using mass spectrometry-based protein identification, we identified several outer membrane proteins, including TonB-dependent receptor transport proteins, that interacted with MreC. Imaging live cells containing fusions of these outer membrane proteins to green fluorescent protein showed that they adopted a subcellular localization pattern that was similar to that of MreC. These results suggest that MreC may function in the spatial organization of PBPs as well as other proteins that lie outside the cytoplasmic membrane. [ABSTRACT FROM AUTHOR]

Defensins are peptides that protect the host against microorganisms. Here we show that the θ-defensin retrocyclin 2 (RC2) inhibited influenza virus infection by blocking membrane fusion mediated by the viral hemagglutinin. RC2 was effective even after hemagglutinin attained a fusogenic conformation or had induced membrane hemifusion. RC2, a multivalent lectin, prevented hemagglutinin-mediated fusion by erecting a network of crosslinked and immobilized surface glycoproteins. RC2 also inhibited fusion mediated by Sindbis virus and baculovirus. Human β-defensin 3 and mannan-binding lectin also blocked viral fusion by creating a protective barricade of immobilized surface proteins. This general mechanism might explain the broad-spectrum antiviral activity of many multivalent lectins of the innate immune system. [ABSTRACT FROM AUTHOR]

Describes the basic mechanisms of nitrification and denitrification in water and soil environments. Use of First-order kinetic for describing the processes; Methods for parameter estimation; Factors effecting nitrification and denitrification.

The purpose of the present study was to establish a water quality model for a river network system in BeijingTianjin, China and to develop a method for estimating parameters in the established model. The Network Grid method, which was used in the study, is based on the solution of optimal problems in the entire river network system. The parameters, the decay rate of total BOD (carbonaceous and nitrogenous), K[sub 1], the re-aeration rate, K[sub 2], the decay rate of BOD for settleable solids, K[sub 3], the DO constant rate for photosynthesis, K[sub 4], and the nitrification rate of ammonia, K[sub 5], in network models are estimated simultaneously by the Network Grid method. The comparison of results indicates that the Network Grid method is suitable for the estimation of the parameters in river network model and the concentration distribution of organic pollutants calculated by the model is in accordance with that observed in situ. [ABSTRACT FROM AUTHOR]