Time-course variation of lipid and carotenoid production under high light (300 mE/m 2 s) and nitr... more Time-course variation of lipid and carotenoid production under high light (300 mE/m 2 s) and nitrogen starvation conditions was determined in a Dunaliella tertiolecta strain. Nanoelectrospray (nanoESI) chip based direct infusion was used for lipid analysis and ultra-performance liquid chromatography (UPLC) coupled with a photodiode array (PDA) or atmospheric chemical ionization mass spectrometry (APCI-MS) was used for carotenoid analysis. A total of 29 lipids and 7 carotenoids were detected. Alterations to diacylglyceryltrimethylhomoserine (DGTS) and digalactosyldiacylglycerol (DGDG) species were significant observations under stress conditions. Their role in relation to the regulation of photosynthesis under stress condition is discussed in this study. The total carotenoid content was decreased under stress conditions, while ã-carotene was increased under nitrate-deficient cultivation. The highest productivity of carotenoid was attained under high light and nitrate sufficiency (HLNS) condition, which result from the highest level of biomass under HLNS. When stress was induced at stationary phase, the substantial changes to the lipid composition occurred, and the higher carotenoid content and productivity were exhibited. This is the first report to investigate the variation of lipids, including glycerolipid, glycerophospholipid, and carotenoid in D. tertiolecta in response to stress conditions using lipidomics tools.
In this study, patterns of proteome expression were monitored and specifically expressed proteins... more In this study, patterns of proteome expression were monitored and specifically expressed proteins in human milk were detected in collected human milk after 1 week, 3 weeks, and 6 weeks from delivery. A quantitative shotgun proteomic approach was used to identify human milk proteins and reveal their relative expression amounts. For each sample, two independent human milk samples from two mothers were pooled, and then three replicated shotgun proteomic analyses were carried out. Casein, which is a highly abundant protein in human milk, was removed, and then trypsin was treated to produce a digested peptide mixture. The peptides were loaded in the home-made reversed-phase C18 fused-silica capillary column, and then the eluted peptides were analyzed by using a linear ion-trap mass spectrometer. The relative quantitation of proteins was performed by the normalized spectral count method. For each sample, 81-109 non-redundant proteins were identified. The identified proteins consisted of glycoproteins, metabolic enzyme, and chaperon enzymes such as lactoferrin, carboxylic ester hydrolase, and clusterin. The comparative analysis for the 63 proteins, which were reproducibly identified in all three replications, revealed that 25 proteins were statically significant differentially expressed. Among the differentially expressed proteins, Ig lambda-7 chain C region and tenascin drastically decreased with the delivery time.
Synechocystis sp. PCC 7338 (hereafter referred to as Synechocystis 7338) is a marine cyanobacteri... more Synechocystis sp. PCC 7338 (hereafter referred to as Synechocystis 7338) is a marine cyanobacterium that has the potential to produce photosynthetic pigments. In this study, we investigated the effects of various NaCl concentrations (0, 0.4, 0.8, and 1.2 M) on cell growth, photosynthetic pigments, and metabolites and intact lipid species profiles in Synechocystis 7338. The overall growth pattern of Synechocystis 7338 was similar under 0, 0.4, and 0.8 M NaCl conditions. Cell growth was retarded after reaching the exponential phase under 1.2 M NaCl; however, a similar growth pattern was observed after the exponential phase under 0.4 M NaCl (control group). The highest production of chlorophyll a (4.18 mg L −1), allophycocyanin (4.08 mg L −1), and phycoerythrin (1.70 mg L −1) were achieved under 1.2 M NaCl conditions. Altered metabolic and lipidomic profiles were observed at different NaCl conditions; significantly increased relative yields of glucosylglycerol, one diacylglyceryltrimethylhomoserine, one monogalactosyldiacylglycerol, and four phosphatidylglycerol species were observed under 1.2 M NaCl conditions using gas chromatography-mass spectrometry and direct infusion-mass spectrometry analyses. In addition, it was revealed that the photosynthetic activity recovered under 1.2 M NaCl conditions in long-term culture. Hydrogen peroxide content significantly increased under 1.2 M NaCl conditions. It is believed that glutathione content also significantly increased under high salinity conditions to retain the normal functioning of Synechocystis 7338. These results indicate that high salinity conditions for Synechocystis 7338 culture could be used for the large-scale production of chlorophyll a, allophycocyanin, phycoerythrin, and other bioactive metabolites.
Cyanobacteria are a compelling biochemical production platform for their ability to propagate usi... more Cyanobacteria are a compelling biochemical production platform for their ability to propagate using light and atmospheric CO 2 via photosynthesis. However, the engineering of strains is hampered by limited understanding of photosynthesis under diverse environmental conditions such as high-light and low-temperature stresses.
Comparison of number of -linked glycosites commonly or uniquely detected from plasma and tissues/cells
<b>Copyright information:</b>Taken from "UniPep - a database for human -linked g... more <b>Copyright information:</b>Taken from "UniPep - a database for human -linked glycosites: a resource for biomarker discovery"Genome Biology 2006;7(8):R73-R73.Published online 10 Aug 2006PMCID:PMC1779586. Shows the overlap of -linked glycosites identified in plasma with tissues or cells.
Cyanobacteria are considered as promising microbial cell factories producing a wide array of bio-... more Cyanobacteria are considered as promising microbial cell factories producing a wide array of bio-products. Among them, Synechocystis sp. PCC 7338 has the advantage of growing in seawater, rather than requiring arable land or freshwater. Nonetheless, how this marine cyanobacterium grows under the high salt stress condition remains unknown. Here, we determined its complete genome sequence with the embedded regulatory elements and analyzed the transcriptional changes in response to a high-salt environment. Complete genome sequencing revealed a 3.70 mega base pair genome and three plasmids with a total of 3,589 genes annotated. Differential RNA-seq and Term-seq data aligned to the complete genome provided genome-wide information on genetic regulatory elements, including promoters, ribosome-binding sites, 5′- and 3′-untranslated regions, and terminators. Comparison with freshwater Synechocystis species revealed Synechocystis sp. PCC 7338 genome encodes additional genes, whose functions a...
Synechocystis strains are considered as valuable resources for production of useful metabolites. ... more Synechocystis strains are considered as valuable resources for production of useful metabolites. Comparative primary metabolic and lipidomic profiling of freshwater and marine Synechocystis strains is needed to understand the physiological characteristics of each strain at molecular level. In this study, we performed comparative primary metabolic and lipidomic profiling of freshwater Synechocystis sp. PCC 6803 (hereafter Synechocystis 6803) and marine Synechocystis sp. PCC 7338 (hereafter Synechocystis 7338) by using gas chromatography-mass spectrometry and nano electrospray ionization-mass spectrometry. Neophytadiene, phytol, monogalactosyldiacylglycerol (MGDG), and digalactosyldiacylglycerol (DGDG) were significantly higher in Synechocystis 6803. Levels of alanine, aspartic acid, valine, linoleic acid, linolenic acid, oleic acid, plamitic acid, stearic acid, glucosylglycerol, sucrose, phosphatidylglycerol (PG), and diacylglyceryltrimethylhomoserine (DGTS) (only detected in Synechocystis 7338) were significantly higher in Synechocystis 7338. Our results provide basic information to choose Synechocystis strains for various industrial usages, and also provide fundamental information on the future development of novel Synechocystis strains to produce high levels of specific metabolites by metabolic pathway modulation.
Deacylated lipooligosaccharides (dLOSs) were developed as human vaccine adjuvants. The dLOSs have... more Deacylated lipooligosaccharides (dLOSs) were developed as human vaccine adjuvants. The dLOSs have significant immune activities and markedly lower toxicities than their precursors, lipopolysaccharides (LPSs). In this study, we developed a novel liquid chromatography mass spectrometry (LC–MS) method for characterization of the dLOSs. The structural identification and characterization of the dLOSs were carried out using electrospray ionization tandem mass spectrometric experiments. Finally, we propose the most likely structure of the dLOSs as being composed of a diacyl form of lipid A with seven sugars, 3 HEP + 2 KDO + 1 GlcN + 1 Glc.
Mesenchymal stem cells (MSCs) have been investigated to treat liver diseases, but the efficiency ... more Mesenchymal stem cells (MSCs) have been investigated to treat liver diseases, but the efficiency of MSCs to treat chronic liver diseases is conflicting. FGF21 can reduce inflammation and fibrosis. We established FGF21‐secreting adipose derived stem cells (FGF21_ADSCs) to enhance the effects of ADSCs and transplanted them into thioacetamide (TAA)‐induced liver fibrosis mice via the tail vein. Transplantation of FGF21_ADSCs significantly improved liver fibrosis by decreasing serum hyaluronic acid and reducing the expression of fibrosis‐related factors such as α‐smooth muscle actin (α‐SMA), collagen and tissue inhibitor of metalloproteinase‐1 (TIMP‐1) compared with the Empty_ADSCs by inhibition of p‐JNK, NF‐κB and p‐Smad2/3 signalling. α‐lactoalbumin (LA) and lactotransferrin (LTF), secretory factors produced from FGF21_ADSCs inhibited TGF‐β1‐induced expression of α‐SMA and collagen in LX‐2 cells. These results suggest that transplantation of FGF21_ADSCs inhibited liver fibrosis more e...
Methionine (Met) is involved in one-carbon de novo nucleotide synthesis and is an essential amino... more Methionine (Met) is involved in one-carbon de novo nucleotide synthesis and is an essential amino acid for cell survival. The impact of lactate calcium salt (CaLa) on the Met metabolism was investigated to evaluate the enhanced antitumor effect of methotrexate (MTX) on colorectal cancer (CRC) cells. Met dependency relating to homocysteine (Hcy) and betaine was investigated in human CRC cells (HCT-116 and HT-29) using a viability assay and liquid chromatography-mass spectrometry. Expression of betaine transporter-1 (BGT-1) following treatment with MTX alone or with CaLa was determined by Western blot. Enhanced antitumor effect due to malfunction of Met synthesis was confirmed. CRC cell viability decreased in Met-restricted medium, but was maintained after Hcy and betaine treatment while overcoming Met restriction. BGT-1 expression was downregulated following the treatment of dose-increased CaLa, whereas there was no effect on BGT-1 expression after MTX treatment. CaLa in combination ...
Determining the Particle Size Distributions of Titanium Dioxide Using Sedimentation Field-Flow Fractionation and Photon Correlation Spectroscopy
ACS Symposium Series, 2001
... Page 11. 295 10 20 30 40 50 60 Time (min) Figure 4. Superimposed SdFFF fractograms of two T1O... more ... Page 11. 295 10 20 30 40 50 60 Time (min) Figure 4. Superimposed SdFFF fractograms of two T1O2 samples. The carrier liquid was 0.1% Fl-70 and 0.02% sodium azide and the channel flow rate was 4.1 mL/min. ... 19. Williams, SKR; Lee, H.; Turner, MM J. Magn. Magn. ...
World journal of gastroenterology : WJG, Jan 7, 2014
Recent advances in genomic medicine have opened up the possibility of tailored medicine that may ... more Recent advances in genomic medicine have opened up the possibility of tailored medicine that may eventually replace traditional "one-size-fits all" approaches to the treatment of inflammatory bowel disease (IBD). In addition to exploring the interactions between hosts and microbes, referred to as the microbiome, a variety of strategies that can be tailored to an individual in the coming era of personalized medicine in the treatment of IBD are being investigated. These include prompt genomic screening of patients at risk of developing IBD, the utility of molecular discrimination of IBD subtypes among patients diagnosed with IBD, and the discovery of proteome biomarkers to diagnose or predict cancer risks. Host genetic factors influence the etiology of IBD, as do microbial ecosystems in the human bowel, which are not uniform, but instead represent many different microhabitats that can be influenced by diet and might affect processes essential to bowel metabolism. Further adv...
Evaluation of Different Field-Flow Fractionation Techniques for Separating Bacteria
Separation Science and Technology, 2000
... 4 Fractograms of live and dead P. putida, (a) Sedimentation FFF (flow rate = 3.84 mL-min-1, 1... more ... 4 Fractograms of live and dead P. putida, (a) Sedimentation FFF (flow rate = 3.84 mL-min-1, 1000 rpm, stopflow time = 2 minutes, carrier liquid is deionized water containing 0.1% FL-70, 0.02% NaN3). ... JF Ranville, H. Lee, and SKR Williams, Ibid., In Preparation. ...
A microcapillary trap cartridge-microcapillary high-performance liquid chromatography electrospray ionization emitter device capable of peptide tandem mass spectrometry at the attomole level on an ion trap mass spectrometer with automated routine operation
Rapid Communications in Mass Spectrometry, 2003
Reversed-phase microcapillary chromatography (RP-microLC) combined with electrospray ionization t... more Reversed-phase microcapillary chromatography (RP-microLC) combined with electrospray ionization tandem mass spectrometry (ESI-MS/MS) is one of two prevailing techniques in proteomic analysis, the other being matrix-assisted laser desorption/ionization (MALDI). Despite the arguably better dynamic range obtainable with ESI, MALDI is increasingly popular due to ease of use, ruggedness and the ability to decouple separation from ionization. By contrast, in order to take advantage of the sensitivity and dynamic range afforded by the concentration-dependent nature of ESI, it is directly coupled to separations that take place in small i.d. RP-microLC columns. This gain in sensitivity often comes at a loss of ruggedness due to clogging of the small i.d. RP-microLC columns, one result of which is limited sample throughput. Here we describe a combined micropre-column-microLC-ESI device that is sensitive, rugged and modular in design allowing facile construction and troubleshooting. Due to low signal-to-noise as little as 1 attomole of a peptide can be selected by data-dependent methods for collision-induced dissociation. Importantly, the resulting tandem mass spectrum is of high enough quality to identify the peptide sequence by a database search against a complex database using SEQUEST. Finally, the device is demonstrated to be rugged as judged by &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;60 consecutive reversed-phase microLC separations on complex peptide mixtures before chromatographic resolution is degraded.
Cystic fibrosis transmembrane conductance regulator (CFTR) is a cell-surface anion channel that p... more Cystic fibrosis transmembrane conductance regulator (CFTR) is a cell-surface anion channel that permeates chloride and bicarbonate ions. The most frequent mutation of CFTR that causes cystic fibrosis is the deletion of phenylalanine at position 508 (ΔF508), which leads to defects in protein folding and cellular trafficking to the plasma membrane. The lack of the cell-surface CFTR results in a reduction in the lifespan due to chronic lung infection with progressive deterioration of lung function. Hsc70 plays a crucial role in degradation of mutant CFTR by the ubiquitinÀproteasome system. To date, various Hsc70 inhibitors and transcription regulators have been tested to determine whether they correct the defective activity of mutant CFTR. However, they exhibited limited or questionable effects on restoring the chloride channel activity in cystic fibrosis cells. Herein, we show that a small molecule apoptozole (Az) has high cellular potency to promote membrane trafficking of mutant CFTR and its chloride channel activity in cystic fibrosis cells. Results from affinity chromatography and ATPase activity assay indicate that Az inhibits the ATPase activity of Hsc70 by binding to its ATPase domain. In addition, a ligand-directed protein labeling and molecular modeling studies also suggest the binding of Az to an ATPase domain, in particular, an ATP-binding pocket. It is proposed that Az suppresses ubiquitination of ΔF508-CFTR maybe by blocking interaction of the mutant with Hsc70 and CHIP, and, as a consequence, it enhances membrane trafficking of the mutant.
Time-course variation of lipid and carotenoid production under high light (300 mE/m 2 s) and nitr... more Time-course variation of lipid and carotenoid production under high light (300 mE/m 2 s) and nitrogen starvation conditions was determined in a Dunaliella tertiolecta strain. Nanoelectrospray (nanoESI) chip based direct infusion was used for lipid analysis and ultra-performance liquid chromatography (UPLC) coupled with a photodiode array (PDA) or atmospheric chemical ionization mass spectrometry (APCI-MS) was used for carotenoid analysis. A total of 29 lipids and 7 carotenoids were detected. Alterations to diacylglyceryltrimethylhomoserine (DGTS) and digalactosyldiacylglycerol (DGDG) species were significant observations under stress conditions. Their role in relation to the regulation of photosynthesis under stress condition is discussed in this study. The total carotenoid content was decreased under stress conditions, while ã-carotene was increased under nitrate-deficient cultivation. The highest productivity of carotenoid was attained under high light and nitrate sufficiency (HLNS) condition, which result from the highest level of biomass under HLNS. When stress was induced at stationary phase, the substantial changes to the lipid composition occurred, and the higher carotenoid content and productivity were exhibited. This is the first report to investigate the variation of lipids, including glycerolipid, glycerophospholipid, and carotenoid in D. tertiolecta in response to stress conditions using lipidomics tools.
In this study, patterns of proteome expression were monitored and specifically expressed proteins... more In this study, patterns of proteome expression were monitored and specifically expressed proteins in human milk were detected in collected human milk after 1 week, 3 weeks, and 6 weeks from delivery. A quantitative shotgun proteomic approach was used to identify human milk proteins and reveal their relative expression amounts. For each sample, two independent human milk samples from two mothers were pooled, and then three replicated shotgun proteomic analyses were carried out. Casein, which is a highly abundant protein in human milk, was removed, and then trypsin was treated to produce a digested peptide mixture. The peptides were loaded in the home-made reversed-phase C18 fused-silica capillary column, and then the eluted peptides were analyzed by using a linear ion-trap mass spectrometer. The relative quantitation of proteins was performed by the normalized spectral count method. For each sample, 81-109 non-redundant proteins were identified. The identified proteins consisted of glycoproteins, metabolic enzyme, and chaperon enzymes such as lactoferrin, carboxylic ester hydrolase, and clusterin. The comparative analysis for the 63 proteins, which were reproducibly identified in all three replications, revealed that 25 proteins were statically significant differentially expressed. Among the differentially expressed proteins, Ig lambda-7 chain C region and tenascin drastically decreased with the delivery time.
Synechocystis sp. PCC 7338 (hereafter referred to as Synechocystis 7338) is a marine cyanobacteri... more Synechocystis sp. PCC 7338 (hereafter referred to as Synechocystis 7338) is a marine cyanobacterium that has the potential to produce photosynthetic pigments. In this study, we investigated the effects of various NaCl concentrations (0, 0.4, 0.8, and 1.2 M) on cell growth, photosynthetic pigments, and metabolites and intact lipid species profiles in Synechocystis 7338. The overall growth pattern of Synechocystis 7338 was similar under 0, 0.4, and 0.8 M NaCl conditions. Cell growth was retarded after reaching the exponential phase under 1.2 M NaCl; however, a similar growth pattern was observed after the exponential phase under 0.4 M NaCl (control group). The highest production of chlorophyll a (4.18 mg L −1), allophycocyanin (4.08 mg L −1), and phycoerythrin (1.70 mg L −1) were achieved under 1.2 M NaCl conditions. Altered metabolic and lipidomic profiles were observed at different NaCl conditions; significantly increased relative yields of glucosylglycerol, one diacylglyceryltrimethylhomoserine, one monogalactosyldiacylglycerol, and four phosphatidylglycerol species were observed under 1.2 M NaCl conditions using gas chromatography-mass spectrometry and direct infusion-mass spectrometry analyses. In addition, it was revealed that the photosynthetic activity recovered under 1.2 M NaCl conditions in long-term culture. Hydrogen peroxide content significantly increased under 1.2 M NaCl conditions. It is believed that glutathione content also significantly increased under high salinity conditions to retain the normal functioning of Synechocystis 7338. These results indicate that high salinity conditions for Synechocystis 7338 culture could be used for the large-scale production of chlorophyll a, allophycocyanin, phycoerythrin, and other bioactive metabolites.
Cyanobacteria are a compelling biochemical production platform for their ability to propagate usi... more Cyanobacteria are a compelling biochemical production platform for their ability to propagate using light and atmospheric CO 2 via photosynthesis. However, the engineering of strains is hampered by limited understanding of photosynthesis under diverse environmental conditions such as high-light and low-temperature stresses.
Comparison of number of -linked glycosites commonly or uniquely detected from plasma and tissues/cells
<b>Copyright information:</b>Taken from "UniPep - a database for human -linked g... more <b>Copyright information:</b>Taken from "UniPep - a database for human -linked glycosites: a resource for biomarker discovery"Genome Biology 2006;7(8):R73-R73.Published online 10 Aug 2006PMCID:PMC1779586. Shows the overlap of -linked glycosites identified in plasma with tissues or cells.
Cyanobacteria are considered as promising microbial cell factories producing a wide array of bio-... more Cyanobacteria are considered as promising microbial cell factories producing a wide array of bio-products. Among them, Synechocystis sp. PCC 7338 has the advantage of growing in seawater, rather than requiring arable land or freshwater. Nonetheless, how this marine cyanobacterium grows under the high salt stress condition remains unknown. Here, we determined its complete genome sequence with the embedded regulatory elements and analyzed the transcriptional changes in response to a high-salt environment. Complete genome sequencing revealed a 3.70 mega base pair genome and three plasmids with a total of 3,589 genes annotated. Differential RNA-seq and Term-seq data aligned to the complete genome provided genome-wide information on genetic regulatory elements, including promoters, ribosome-binding sites, 5′- and 3′-untranslated regions, and terminators. Comparison with freshwater Synechocystis species revealed Synechocystis sp. PCC 7338 genome encodes additional genes, whose functions a...
Synechocystis strains are considered as valuable resources for production of useful metabolites. ... more Synechocystis strains are considered as valuable resources for production of useful metabolites. Comparative primary metabolic and lipidomic profiling of freshwater and marine Synechocystis strains is needed to understand the physiological characteristics of each strain at molecular level. In this study, we performed comparative primary metabolic and lipidomic profiling of freshwater Synechocystis sp. PCC 6803 (hereafter Synechocystis 6803) and marine Synechocystis sp. PCC 7338 (hereafter Synechocystis 7338) by using gas chromatography-mass spectrometry and nano electrospray ionization-mass spectrometry. Neophytadiene, phytol, monogalactosyldiacylglycerol (MGDG), and digalactosyldiacylglycerol (DGDG) were significantly higher in Synechocystis 6803. Levels of alanine, aspartic acid, valine, linoleic acid, linolenic acid, oleic acid, plamitic acid, stearic acid, glucosylglycerol, sucrose, phosphatidylglycerol (PG), and diacylglyceryltrimethylhomoserine (DGTS) (only detected in Synechocystis 7338) were significantly higher in Synechocystis 7338. Our results provide basic information to choose Synechocystis strains for various industrial usages, and also provide fundamental information on the future development of novel Synechocystis strains to produce high levels of specific metabolites by metabolic pathway modulation.
Deacylated lipooligosaccharides (dLOSs) were developed as human vaccine adjuvants. The dLOSs have... more Deacylated lipooligosaccharides (dLOSs) were developed as human vaccine adjuvants. The dLOSs have significant immune activities and markedly lower toxicities than their precursors, lipopolysaccharides (LPSs). In this study, we developed a novel liquid chromatography mass spectrometry (LC–MS) method for characterization of the dLOSs. The structural identification and characterization of the dLOSs were carried out using electrospray ionization tandem mass spectrometric experiments. Finally, we propose the most likely structure of the dLOSs as being composed of a diacyl form of lipid A with seven sugars, 3 HEP + 2 KDO + 1 GlcN + 1 Glc.
Mesenchymal stem cells (MSCs) have been investigated to treat liver diseases, but the efficiency ... more Mesenchymal stem cells (MSCs) have been investigated to treat liver diseases, but the efficiency of MSCs to treat chronic liver diseases is conflicting. FGF21 can reduce inflammation and fibrosis. We established FGF21‐secreting adipose derived stem cells (FGF21_ADSCs) to enhance the effects of ADSCs and transplanted them into thioacetamide (TAA)‐induced liver fibrosis mice via the tail vein. Transplantation of FGF21_ADSCs significantly improved liver fibrosis by decreasing serum hyaluronic acid and reducing the expression of fibrosis‐related factors such as α‐smooth muscle actin (α‐SMA), collagen and tissue inhibitor of metalloproteinase‐1 (TIMP‐1) compared with the Empty_ADSCs by inhibition of p‐JNK, NF‐κB and p‐Smad2/3 signalling. α‐lactoalbumin (LA) and lactotransferrin (LTF), secretory factors produced from FGF21_ADSCs inhibited TGF‐β1‐induced expression of α‐SMA and collagen in LX‐2 cells. These results suggest that transplantation of FGF21_ADSCs inhibited liver fibrosis more e...
Methionine (Met) is involved in one-carbon de novo nucleotide synthesis and is an essential amino... more Methionine (Met) is involved in one-carbon de novo nucleotide synthesis and is an essential amino acid for cell survival. The impact of lactate calcium salt (CaLa) on the Met metabolism was investigated to evaluate the enhanced antitumor effect of methotrexate (MTX) on colorectal cancer (CRC) cells. Met dependency relating to homocysteine (Hcy) and betaine was investigated in human CRC cells (HCT-116 and HT-29) using a viability assay and liquid chromatography-mass spectrometry. Expression of betaine transporter-1 (BGT-1) following treatment with MTX alone or with CaLa was determined by Western blot. Enhanced antitumor effect due to malfunction of Met synthesis was confirmed. CRC cell viability decreased in Met-restricted medium, but was maintained after Hcy and betaine treatment while overcoming Met restriction. BGT-1 expression was downregulated following the treatment of dose-increased CaLa, whereas there was no effect on BGT-1 expression after MTX treatment. CaLa in combination ...
Determining the Particle Size Distributions of Titanium Dioxide Using Sedimentation Field-Flow Fractionation and Photon Correlation Spectroscopy
ACS Symposium Series, 2001
... Page 11. 295 10 20 30 40 50 60 Time (min) Figure 4. Superimposed SdFFF fractograms of two T1O... more ... Page 11. 295 10 20 30 40 50 60 Time (min) Figure 4. Superimposed SdFFF fractograms of two T1O2 samples. The carrier liquid was 0.1% Fl-70 and 0.02% sodium azide and the channel flow rate was 4.1 mL/min. ... 19. Williams, SKR; Lee, H.; Turner, MM J. Magn. Magn. ...
World journal of gastroenterology : WJG, Jan 7, 2014
Recent advances in genomic medicine have opened up the possibility of tailored medicine that may ... more Recent advances in genomic medicine have opened up the possibility of tailored medicine that may eventually replace traditional "one-size-fits all" approaches to the treatment of inflammatory bowel disease (IBD). In addition to exploring the interactions between hosts and microbes, referred to as the microbiome, a variety of strategies that can be tailored to an individual in the coming era of personalized medicine in the treatment of IBD are being investigated. These include prompt genomic screening of patients at risk of developing IBD, the utility of molecular discrimination of IBD subtypes among patients diagnosed with IBD, and the discovery of proteome biomarkers to diagnose or predict cancer risks. Host genetic factors influence the etiology of IBD, as do microbial ecosystems in the human bowel, which are not uniform, but instead represent many different microhabitats that can be influenced by diet and might affect processes essential to bowel metabolism. Further adv...
Evaluation of Different Field-Flow Fractionation Techniques for Separating Bacteria
Separation Science and Technology, 2000
... 4 Fractograms of live and dead P. putida, (a) Sedimentation FFF (flow rate = 3.84 mL-min-1, 1... more ... 4 Fractograms of live and dead P. putida, (a) Sedimentation FFF (flow rate = 3.84 mL-min-1, 1000 rpm, stopflow time = 2 minutes, carrier liquid is deionized water containing 0.1% FL-70, 0.02% NaN3). ... JF Ranville, H. Lee, and SKR Williams, Ibid., In Preparation. ...
A microcapillary trap cartridge-microcapillary high-performance liquid chromatography electrospray ionization emitter device capable of peptide tandem mass spectrometry at the attomole level on an ion trap mass spectrometer with automated routine operation
Rapid Communications in Mass Spectrometry, 2003
Reversed-phase microcapillary chromatography (RP-microLC) combined with electrospray ionization t... more Reversed-phase microcapillary chromatography (RP-microLC) combined with electrospray ionization tandem mass spectrometry (ESI-MS/MS) is one of two prevailing techniques in proteomic analysis, the other being matrix-assisted laser desorption/ionization (MALDI). Despite the arguably better dynamic range obtainable with ESI, MALDI is increasingly popular due to ease of use, ruggedness and the ability to decouple separation from ionization. By contrast, in order to take advantage of the sensitivity and dynamic range afforded by the concentration-dependent nature of ESI, it is directly coupled to separations that take place in small i.d. RP-microLC columns. This gain in sensitivity often comes at a loss of ruggedness due to clogging of the small i.d. RP-microLC columns, one result of which is limited sample throughput. Here we describe a combined micropre-column-microLC-ESI device that is sensitive, rugged and modular in design allowing facile construction and troubleshooting. Due to low signal-to-noise as little as 1 attomole of a peptide can be selected by data-dependent methods for collision-induced dissociation. Importantly, the resulting tandem mass spectrum is of high enough quality to identify the peptide sequence by a database search against a complex database using SEQUEST. Finally, the device is demonstrated to be rugged as judged by &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;60 consecutive reversed-phase microLC separations on complex peptide mixtures before chromatographic resolution is degraded.
Cystic fibrosis transmembrane conductance regulator (CFTR) is a cell-surface anion channel that p... more Cystic fibrosis transmembrane conductance regulator (CFTR) is a cell-surface anion channel that permeates chloride and bicarbonate ions. The most frequent mutation of CFTR that causes cystic fibrosis is the deletion of phenylalanine at position 508 (ΔF508), which leads to defects in protein folding and cellular trafficking to the plasma membrane. The lack of the cell-surface CFTR results in a reduction in the lifespan due to chronic lung infection with progressive deterioration of lung function. Hsc70 plays a crucial role in degradation of mutant CFTR by the ubiquitinÀproteasome system. To date, various Hsc70 inhibitors and transcription regulators have been tested to determine whether they correct the defective activity of mutant CFTR. However, they exhibited limited or questionable effects on restoring the chloride channel activity in cystic fibrosis cells. Herein, we show that a small molecule apoptozole (Az) has high cellular potency to promote membrane trafficking of mutant CFTR and its chloride channel activity in cystic fibrosis cells. Results from affinity chromatography and ATPase activity assay indicate that Az inhibits the ATPase activity of Hsc70 by binding to its ATPase domain. In addition, a ligand-directed protein labeling and molecular modeling studies also suggest the binding of Az to an ATPase domain, in particular, an ATP-binding pocket. It is proposed that Az suppresses ubiquitination of ΔF508-CFTR maybe by blocking interaction of the mutant with Hsc70 and CHIP, and, as a consequence, it enhances membrane trafficking of the mutant.
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