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111.
112.
The objective of this study was to develop and apply a novel multiplex panel of solid-phase proximity ligation assays (SP-PLA) requiring only 20 μL of samples, as a tool for discovering protein biomarkers for neurological disease and treatment thereof in cerebrospinal fluid (CSF). We applied the SP-PLA to samples from two sets of patients with poorly understood nervous system pathologies amyotrophic lateral sclerosis (ALS) and neuropathic pain, where patients were treated with spinal cord stimulation (SCS). Forty-seven inflammatory and neurotrophic proteins were measured in samples from 20 ALS patients and 15 neuropathic pain patients, and compared to normal concentrations in CSF from control individuals. Nineteen of the 47 proteins were detectable in more than 95% of the 72 controls. None of the 21 proteins detectable in CSF from neuropathic pain patients were significantly altered by SCS. The levels of the three proteins, follistatin, interleukin-1 alpha, and kallikrein-5 were all significantly reduced in the ALS group compared to age-matched controls. These results demonstrate the utility of purpose designed multiplex SP-PLA panels in CSF biomarker research for understanding neuropathological and neurotherapeutic mechanisms. The protein changes found in the CSF of ALS patients may be of diagnostic interest.  相似文献   
113.
Narcissiflorine, narcissiflorinine and narcissifloridine, three new saponins, have been isolated from the ethanolic extract of Anemone narcissiflora (Ranunculaceae). The structural elucidation of narcissiflorine, narcissiflorinine and narcissifloridine has showed them to be [α-l-arabinofuranosyl-(1 → 4)-β-d-glucuronopyranosyl-(1→3)]- 3β-hydroxy-olean-12-en-28-oic acid, [α,-l-arabinofuranosyl-(1→2)-α-l-rhamnopyranosyl-(1→4)-β-d- glucuronypyranosyl(1→3)]-3-β-hydroxy-olean-12-en-28-oic acid and [α-l-arabinofuranosyl-(1→2)-α-l- rhamnopyranosyl-(1→4)-β-d-glucopyranosyl-(1→3)]-3-β-hydroxy-olean-12-en-28-oic acid, respectively.  相似文献   
114.
INTRODUCTION: The incidence of Barrett esophageal adenocarcinoma (BEAC) has been increasing at an alarming rate in western countries. In this study, we have evaluated the therapeutic potential of sulforaphane (SFN), an antioxidant derived from broccoli, in BEAC. METHODS: BEAC cells were treated with SFN, alone or in combination with chemotherapeutic, paclitaxel, or telomerase-inhibiting agents (MST-312, GRN163L), and live cell number determined at various time points. The effect on drug resistance/chemosensitivity was evaluated by rhodamine efflux assay. Apoptosis was detected by annexin V labeling and Western blot analysis of poly(ADP-ribose) polymerase cleavage. Effects on genes implicated in cell cycle and apoptosis were determined by Western blot analyses. To evaluate the efficacy in vivo, BEAC cells were injected subcutaneously in severe combined immunodeficient mice, and after the appearance of palpable tumors, mice were treated with SFN. RESULTS: SFN induced both time- and dose-dependent decline in cell survival, cell cycle arrest, and apoptosis. The treatment with SFN also suppressed the expression of multidrug resistance protein, reduced drug efflux, and increased anticancer activity of other antiproliferative agents including paclitaxel. A significant reduction in tumor volume was also observed by SFN in a subcutaneous tumor model of BEAC. Anticancer activity could be attributed to the induction of caspase 8 and p21 and down-regulation of hsp90, a molecular chaperon required for activity of several proliferation-associated proteins. CONCLUSIONS: These data indicate that a natural product with antioxidant properties from broccoli has great potential to be used in chemoprevention and treatment of BEAC.  相似文献   
115.
Sphingomyelin (SM) and ceramide-phosphoethanolamines (cer-PEs) are related lipids present in mammals and insects, respectively. Owing to the critical roles that cer-PEs play in eukaryotic cellular function, there is a need to develop methods that provide accurate quantitation of these compounds. Results obtained in this study demonstrate that Drosophila contains cer-PEs with unsaturated sphingoid base cores as well as low levels of cer-PEs that possess saturated sphingoid base cores. Specifically, the method developed in this study enabled the quantitation of picogram amounts of cer-PE containing both unsaturated d14:1Δ4 and d16:1Δ4 and saturated d14:0 sphingoid base cores. Using this method, cer-PE compounds with both saturated and unsaturated sphingoid base cores were initially identified by neutral loss scanning, followed by quantitation using selected reaction monitoring (SRM) scans. The SRM scans measured a product ion originating from the sphingoid base backbone, rather than from the head group, increasing the specificity and sensitivity of the quantitation measurement.  相似文献   
116.
Amyloid fibril formation is responsible for several neurodegenerative diseases and are formed when native proteins misfold and stick together with different interactive forces. In the present study, we have determined the mode of interaction of the anionic surfactant sarkosyl with hen egg white lysozyme (HEWL) [EC No. 3.2.1.17] at two pHs (9.0 and 13.0) and investigated its impact on fibrillogenesis. Our data suggested that sarkosyl is promoting amyloid fibril formation in HEWL at the concentration range between 0.9 and 3.0 mM and no amyloid fibril formation was observed in the concentration range of 3.0–20.0 mM at pH 9.0. The results were confirmed by several biophysical and computational techniques, such as turbidity measurement, dynamic light scattering, Raleigh scattering, ThT fluorescence, intrinsic fluorescence, far-UV CD and atomic force microscopy. Sarkosyl was unable to induce aggregation in HEWL at pH 13.0 as confirmed by turbidity and RLS measurements. HEWL forms larger amyloid fibrils in the presence of 1.6 mM of sarkosyl. The spectroscopic, microscopic and molecular docking data suggest that the negatively charged carboxylate group and 12-carbon hydrophobic tail of sarkosyl stimulate amyloid fibril formation in HEWL via electrostatic and hydrophobic interaction. This study leads to new insight into the process of suppression of fibrillogenesis in HEWL which can be prevented by designing ligands that can retard the electrostatic and hydrophobic interaction between sarkosyl and HEWL.  相似文献   
117.
Having a well-known history of genome duplication, rice is a good model for studying structural and functional evolution of paleo duplications. Improved sequence alignment criteria were used to characterize 10 major chromosome-to-chromosome duplication relationships associated with 1440 paralogous pairs, covering 47.8% of the rice genome, with 12.6% of genes that are conserved within sister blocks. Using a micro-array experiment, a genome-wide expression map has been produced, in which 2382 genes show significant differences of expression in root, leaf and grain. By integrating both structural (1440 paralogous pairs) and functional information (2382 differentially expressed genes), we identified 115 paralogous gene pairs for which at least one copy is differentially expressed in one of the three tissues. A vast majority of the 115 paralogous gene pairs have been neofunctionalized or subfunctionalized as 88%, 89% and 96% of duplicates, respectively, expressed in grain, leaf and root show distinct expression patterns. On the basis of a Gene Ontology analysis, we have identified and characterized the gene families that have been structurally and functionally preferentially retained in the duplication showing that the vast majority (>85%) of duplicated have been either lost or have been subfunctionalized or neofunctionalized during 50–70 million years of evolution.  相似文献   
118.
The plant Golgi plays a pivotal role in the biosynthesis of cell wall matrix polysaccharides, protein glycosylation, and vesicle trafficking. Golgi-localized proteins have become prospective targets for reengineering cell wall biosynthetic pathways for the efficient production of biofuels from plant cell walls. However, proteomic characterization of the Golgi has so far been limited, owing to the technical challenges inherent in Golgi purification. In this study, a combination of density centrifugation and surface charge separation techniques have allowed the reproducible isolation of Golgi membranes from Arabidopsis (Arabidopsis thaliana) at sufficiently high purity levels for in-depth proteomic analysis. Quantitative proteomic analysis, immunoblotting, enzyme activity assays, and electron microscopy all confirm high purity levels. A composition analysis indicated that approximately 19% of proteins were likely derived from contaminating compartments and ribosomes. The localization of 13 newly assigned proteins to the Golgi using transient fluorescent markers further validated the proteome. A collection of 371 proteins consistently identified in all replicates has been proposed to represent the Golgi proteome, marking an appreciable advancement in numbers of Golgi-localized proteins. A significant proportion of proteins likely involved in matrix polysaccharide biosynthesis were identified. The potential within this proteome for advances in understanding Golgi processes has been demonstrated by the identification and functional characterization of the first plant Golgi-resident nucleoside diphosphatase, using a yeast complementation assay. Overall, these data show key proteins involved in primary cell wall synthesis and include a mixture of well-characterized and unknown proteins whose biological roles and importance as targets for future research can now be realized.  相似文献   
119.
Development of protective immunity against many pathogens, particularly viruses, requires fine orchestration of both humoral- and cell mediated-immunity. The immunization of animals with soluble antigens usually leads to the induction of humoral immune responses. In contrast, the activation of a cell-mediated immune response against exogenous antigens has always been a challenge, requiring special strategies to expose them to the proteasome, a multifunctional protease complex in the cytosol of the target cells. The degradation of the protein by the cytosolic proteolytic system forms a cardinal step for the induction of cytotoxic T lymphocytes (CTLs). In the present study, we report that a potent primary CTL response against a soluble protein, ovalbumin, can be induced in mice by encapsulating it in the liposomes comprised of Escherichia coli membrane lipids. These lipids were shown to induce strong membrane-membrane fusion as evident from resonance energy transfer and content mixing assays. Furthermore, the fusion of these liposomes with living cells (J774 A1) was demonstrated to result in effective transfer of a fluorescent lipid probe to the plasma membrane of the cells. Moreover, ricin A, a protein synthesis inhibitor that does not cross plasma membrane, was demonstrated to gain access to the cytosol when it was encapsulated in these liposomes. Finally, the liposomes were demonstrated to behave like efficient vehicles for the in vivo delivery of the antigens to the target cells resulting in the elicitation of antigen reactive CD8+ T cell responses.  相似文献   
120.
The present investigation focuses the flow and heat transfer characteristics of the steady three-dimensional Sisko fluid driven by a bidirectional stretching sheet. The modeled partial differential equations are reduced to coupled ordinary differential equations by a suitable transformation. The resulting equations are solved numerically by the shooting method using adaptive Runge Kutta algorithm in combination with Newton''s method in the domain [0,∞). The numerical results for the velocity and temperature fields are graphically presented and effects of the relevant parameters are discussed in detail. Moreover, the skin-friction coefficient and local Nusselt number for different values of the power-law index and stretching ratio parameter are presented through tabulated data. The numerical results are also verified with the results obtained analytically by the homotopy analysis method (HAM). Additionally, the results are validated with previously published pertinent literature as a limiting case of the problem.  相似文献   
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