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1.
Sci Total Environ ; 757: 143820, 2021 Feb 25.
Article in English | MEDLINE | ID: mdl-33248779

ABSTRACT

Biochar, produced as a by-product of pyrolysis/gasification of waste biomass, shows great potential to reduce the environment impact, address the climate change issue, and establish a circular economy model. Despite the promising outlook, the research on the benefits of biochar remains highly debated. This has been attributed to the heterogeneity of biochar itself, with its inherent physical, chemical and biological properties highly influenced by production variables such as feedstock types and treating conditions. Hence, to enable meaningful comparison of results, establishment of an agreed international standard to govern the production of biochar for specific uses is necessary. In this study, we analyzed four key uses of biochar: 1) in agriculture and horticulture, 2) as construction material, 3) as activated carbon, and 4) in anaerobic digestion. Then the guidelines for the properties of biochar, especially for the concentrations of toxic heavy metals, for its environmental friendly application were proposed in the context of Singapore. The international status of the biochar industry code of practice, feedback from Singapore local industry and government agencies, as well as future perspectives for the biochar industry were explained.


Subject(s)
Agriculture , Charcoal , Biomass , Singapore , Soil
2.
J Hazard Mater ; 303: 64-75, 2016 Feb 13.
Article in English | MEDLINE | ID: mdl-26513565

ABSTRACT

Terephthalic acid (TA) is toxic and known as an endocrine disruptor. In this paper, the photocatalytic degradation of TA using sulfated titanium dioxide SO4(2-)/TiO2 photocatalysts was investigated. The photocatalysts were prepared by sol-gel method and characterized by XRD, SEM, BET, ICP/MS and spectroscopic methods. Their activities were compared with bare TiO2 and Degussa P25. The effects of catalyst sulfur content, the initial TA concentration and pre-treatment conditions (O2, N2 or non-pretreated) were studied. O2 functions were also explored. Since there had been no comprehensive study of fluorescent intermediates reported yet, we investigated the intermediates and discovered 5 new intermediates (4 fluorescent and 1 non-fluorescent) which were identified by gas chromatography-mass spectrometry (GC/MS) and fluorescence spectroscopy. These intermediates are complementary to the previously identified carboxylic acid intermediates and might provide new insights to the mechanism of photocatalytic degradation of TA. Since TA is widely used as a probing molecule for photocatalytically generated (·)OH radicals, the ratios of fluorescent intermediates of TA degradation may provide new clues to the photocatalytic activity and mechanism. Based on the results obtained, the possible destruction pathway of TA is also proposed.

3.
Asian Pac J Cancer Prev ; 16(13): 5445-51, 2015.
Article in English | MEDLINE | ID: mdl-26225692

ABSTRACT

Fascin-1 (FSCN1) is an actin-bundling protein that induces cell membrane protrusions, increases cell motility, and is overexpressed in various human epithelial cancers, including esophageal squamous cell carcinoma (ESCC). We analyzed various protein-protein interactions (PPI) of differentially-expressed genes (DEGs), in fascin knockdown ESCC cells, to explore the role of fascin overexpression. The node-degree distributions indicated these PPI sub-networks to be characterized as scale-free. Subcellular localization analysis revealed DEGs to interact with other proteins directly or indirectly, distributed in multiple layers of extracellular membrane-cytoskeleton/ cytoplasm-nucleus. The functional annotation map revealed hundreds of significant gene ontology (GO) terms, especially those associated with cytoskeleton organization of FSCN1. The Random Walk with Restart algorithm was applied to identify the prioritizations of these DEGs when considering their relationship with FSCN1. These analyses based on PPI network have greatly expanded our comprehension of the mRNA expression profile following fascin knockdown to future examine the roles and mechanisms of fascin action.


Subject(s)
Biomarkers, Tumor/genetics , Carcinoma, Squamous Cell/genetics , Carrier Proteins/antagonists & inhibitors , Esophageal Neoplasms/genetics , Gene Expression Regulation, Neoplastic , Gene Regulatory Networks , Microfilament Proteins/antagonists & inhibitors , RNA, Small Interfering/genetics , Biomarkers, Tumor/metabolism , Carcinoma, Squamous Cell/metabolism , Carrier Proteins/genetics , Esophageal Neoplasms/metabolism , Gene Expression Profiling , Humans , Microfilament Proteins/genetics , Protein Interaction Maps , Tumor Cells, Cultured
4.
Sci Rep ; 5: 12010, 2015 Jul 01.
Article in English | MEDLINE | ID: mdl-26131602

ABSTRACT

The lipocalin proteins (lipocalins) are a large family of small proteins characterized by low sequence similarity and highly conserved crystal structures. Lipocalins have been found to play important roles in many human diseases. For this reason, a systemic analysis of the molecular properties of human lipocalins is essential. In this study, human lipocalins were found to contain four structurally conserved regions (SCRs) and could be divided into two subgroups. A human lipocalin protein-protein interaction network (PPIN) was constructed and integrated with their expression data in esophageal carcinoma. Many lipocalins showed obvious co-expression patterns in esophageal carcinoma. Their subcellular distributions also suggested these lipocalins may transfer signals from the extracellular space to the nucleus using the pathway-like paths. These analyses also expanded our knowledge about this human ancient protein family in the background of esophageal carcinoma.


Subject(s)
Esophageal Neoplasms/metabolism , Lipocalins/metabolism , Amino Acid Sequence , Gene Expression , Humans , Lipocalins/chemistry , Lipocalins/genetics , Molecular Sequence Annotation , Molecular Sequence Data , Protein Interaction Maps , Protein Transport , Retinoblastoma Protein/metabolism , Sequence Homology, Amino Acid , Signal Transduction
5.
Water Res ; 68: 831-8, 2015 Jan 01.
Article in English | MEDLINE | ID: mdl-25465720

ABSTRACT

Recently photocatalytic treatment of municipal reverse osmosis concentrate (ROC) has drawn increasing attention due to its relatively high efficiency and low cost. However, photocatalytic reactions by commercially available TiO2 are not able to degrade fluorosurfactants in the ROC sample due to the absence of photoreactive groups in these compounds. Here we investigated adsorption and coagulation methods and their efficiencies in removing fluorosurfactants. The analysis and characterization methods included mass spectrometry (LC-QToF), total organic carbon (TOC), fluorescence & UV­Visible spectra, SEM, IR, N2 sorption, zeta potential, and elemental analysis. Ferric chloride (FER) coagulation was found to be quite efficient in removing fluorosurfactants, while powdered activated carbon (PAC) adsorption was inefficient. The FER pre-treatment process was found to perform better than the post-treatment process in removing the fluorosurfactants. FER selectively removed the bulky fluorosurfactants with long branches but not the slim ones with short or no branches. At a concentration of 10.60 mM, FER could efficiently remove 62.19% fluorosurfactants in total from the ROC sample. The applicability of Freundlich and Langmuir models for the adsorption processes was also investigated. FER was able to remove fluorosurfactant while PAC unable. While the PAC removal mechanism was adsorption, the FER coagulation mechanism was far more complicated.


Subject(s)
Fluorocarbons/analysis , Surface-Active Agents/analysis , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/analysis , Water Purification/methods , Adsorption , Algorithms , Catalysis/radiation effects , Charcoal/chemistry , Chlorides/chemistry , Ferric Compounds/chemistry , Filtration , Fluorocarbons/chemistry , Microscopy, Electron, Scanning , Models, Chemical , Osmosis , Spectrometry, Fluorescence , Surface-Active Agents/chemistry , Tandem Mass Spectrometry , Water Pollutants, Chemical/chemistry
6.
Reprod Sci ; 22(1): 60-7, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25001019

ABSTRACT

Caloric restriction (CR) is known to increase the number of primordial follicles and prolong the reproductive life span. However, how CR modulates follicular development is not well understood. In the present study, we examined the effects of CR on follicular development in rats and investigated the underlying mechanism. After 10 weeks of CR or high-fat diet, ovarian follicles at different developmental stages were examined by histological analysis. Plasma levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estrogen (ESG) were measured, and the levels of mammalian target of rapamycin (mTOR), p70S6 kinase (p70S6K), and phosphorylated p70S6K in the ovary were detected by Western blot. The results showed that the reserve of follicle pool in CR rats was increased, accompanied by decreased level of phosphorylated p70S6K in the ovary, and decreased serum LH, FSH, and ESG levels. Taken together, these results suggest that CR may suppress ovarian follicular development and enhance the follicle pool reserve by inhibiting mTOR signaling.


Subject(s)
Caloric Restriction , Cell Proliferation , Ovarian Follicle/enzymology , Signal Transduction , TOR Serine-Threonine Kinases/metabolism , Animal Nutritional Physiological Phenomena , Animals , Body Weight , Diet, High-Fat , Estrogens/blood , Female , Follicle Stimulating Hormone/blood , Luteinizing Hormone/blood , Nutritional Status , Phosphorylation , Rats, Sprague-Dawley , Ribosomal Protein S6 Kinases, 70-kDa/metabolism , Time Factors
7.
J Chromatogr A ; 1373: 31-9, 2014 Dec 19.
Article in English | MEDLINE | ID: mdl-25435460

ABSTRACT

Layered double oxide hollow spheres (LDO-HSs) were synthesized and employed as a dissolvable sorbent in dispersive solid-phase extraction (DSPE) to extract eleven United States Environmental Protection Agency's priority phenols from aqueous samples. With their higher specific surface area, LDO-HSs showed much higher extraction efficiency than normal layered double hydroxides and layered double oxides. The entire extraction process was accomplished in a syringe. After DSPE, the sorbent with the analytes was isolated conveniently by directly expelling the spent sample solution out of the syringe. The analyte-enriched sorbent was then subsequently dissolved by withdrawing an acidic solution into the syringe. The final extract was analyzed by high-performance liquid chromatography with ultraviolet detection. The results showed that this method provided low limits of detection for the phenols (0.005-0.153 µg/L), good linearity (r(2)≥ 0.9956) and relative standard deviations of ≤ 6.7%. The optimized method was applied to water samples from 3 rivers. This simple extraction procedure was demonstrated to be a fast, efficient and convenient DSPE approach.


Subject(s)
Chromatography, High Pressure Liquid/methods , Oxides/chemistry , Phenols/analysis , Rivers/chemistry , Solid Phase Extraction/instrumentation , Syringes , Water Pollutants, Chemical/analysis , Hydrogen-Ion Concentration , Limit of Detection , Organic Chemicals , Phenols/chemistry , Solid Phase Extraction/methods , Solubility , Water Pollutants, Chemical/chemistry
8.
Asian Pac J Cancer Prev ; 15(16): 6899-904, 2014.
Article in English | MEDLINE | ID: mdl-25169543

ABSTRACT

NGAL (neutrophil gelatinase-associated lipocalin) is a novel cancer-related protein involves multiple functions in many cancers and other diseases. We previously overexpressed NGAL to analyze its role in esophageal squamous cell carcinoma (ESCC). In this study, a protein-protein interaction (PPI) was constructed and the shortest paths from NGAL to transcription factors in the network were analyzed. We found 28 shortest paths from NGAL to RELA, most of them obeying the principle of extracellular to cytoplasm, then nucleus. These shortest paths were also prioritized according to their normalized intensity from the microarray by the order of interaction cascades. A systems approach was developed in this study by linking differentially expressed genes with publicly available PPI data, Gene Ontology and subcellular localizaton for the integrated analyses. These shortest paths from NGAL to DEG transcription factors or other transcription factors in the PPI network provide important clues for future experimental identification of new pathways.


Subject(s)
Acute-Phase Proteins/genetics , Carcinoma, Squamous Cell/pathology , Esophageal Neoplasms/pathology , Lipocalins/genetics , Protein Interaction Maps/genetics , Proto-Oncogene Proteins/genetics , Transcription Factors/genetics , Acute-Phase Proteins/biosynthesis , Acute-Phase Proteins/metabolism , Cell Line, Tumor , Esophageal Squamous Cell Carcinoma , Humans , Lipocalin-2 , Lipocalins/biosynthesis , Lipocalins/metabolism , Proto-Oncogene Proteins/biosynthesis , Proto-Oncogene Proteins/metabolism , RNA, Messenger/biosynthesis
9.
Gene ; 523(1): 82-7, 2013 Jul 01.
Article in English | MEDLINE | ID: mdl-23566837

ABSTRACT

To maintain the normal length of female reproductive life, the majority of primordial follicles must be maintained in a quiescent state for later use. In this study, we aimed to study the effects of rapamycin on primordial follicle development and investigate the role of mTOR and sirtuin signaling. Rats were treated every other day with an intraperitoneal injection of rapamycin (5mg/kg) or vehicle. After 10weeks of treatment, ovaries were harvested for hematoxylin and eosin (HE) staining, and analysis by immunohistochemistry and Western blotting. HE staining showed that the number and percentage of primordial follicles in the rapamycin-treated group were twice the control group (P<0.001). Immunohistochemical analysis showed that mTOR and phosphorylated-p70S6K were extensively expressed in surviving follicles with strong staining observed in the cytoplasm of the oocyte. Western blotting showed decreased expression of phosphorylated mTOR and phosphorylated p70S6K in the rapamycin-treated group, and increased the expression of both SIRT1 and SIRT6 compared to the control group (P<0.05). Taken together, these results suggest that rapamycin may inhibit the transition from primordial to developing follicles and preserve the follicle pool reserve, thus extending the ovarian lifespan of female rats via the modulation of mTOR and sirtuin signalings.


Subject(s)
Ovarian Follicle/drug effects , Sirolimus/pharmacology , Sirtuin 2/metabolism , TOR Serine-Threonine Kinases/metabolism , Animals , Body Weight/drug effects , Cytoplasm/metabolism , Eating/drug effects , Eosine Yellowish-(YS)/metabolism , Estrous Cycle/physiology , Female , Fertility/drug effects , Hematoxylin/metabolism , Male , Oocytes/metabolism , Organ Size , Ovarian Follicle/metabolism , Ovarian Follicle/physiology , Phosphorylation , Rats , Rats, Sprague-Dawley , Ribosomal Protein S6 Kinases/genetics , Ribosomal Protein S6 Kinases/metabolism , Signal Transduction , Sirtuin 2/genetics , Sirtuins/genetics , Sirtuins/metabolism , TOR Serine-Threonine Kinases/genetics , Time Factors
10.
Aging Clin Exp Res ; 24(2): 125-33, 2012 Apr.
Article in English | MEDLINE | ID: mdl-21502801

ABSTRACT

BACKGROUND AND AIMS: Caloric restriction (CR) extends mammals' lifespans and suppresses ovary development. Sirtuins are involved in these mechanisms. If, and to what extent CR affects ovarian lifespan and follicle development is largely unknown. We investigated the effects of moderate and severe caloric restriction compared with a high-fat dietary regimen on ovarian follicle reserves in rats. METHODS: Female Sprague-Dawley rats (n=48) randomly divided into four groups including normal control (NC), 25% caloric restriction (MCR), 45% CR (SCR) and high-fat diet (HF) were maintained on these regimens for 2 months. RESULTS: Histological analysis showed that both the 25 and 45% CR rats had a significantly higher percentage of primordial follicles and a larger number of healthy follicles than the NC rats, whereas the HF rats did not differ significantly from the NC rats. Immunohistochemical analysis revealed that SIRT1 and SIRT6 proteins were present in the nucleus and cytoplasm of the oocytes. The 25% CR diet increased the expression of both SIRT1 and SIRT6 in the ovary, whereas the 45% CR and HF diets caused a decrease in SIRT1 expression. The level of SIRT6 protein did not change with the 45% CR diet, and it appeared slightly lower in the HF than in the NC groups. CONCLUSIONS: Caloric restriction may inhibit the transition from primordial to developing follicles and extend the entire growth phase of a follicle to preserve the reserve of germ cells. SIRT1 and SIRT6 are both associated with these effects.


Subject(s)
Caloric Restriction , Diet, High-Fat , Ovarian Follicle/metabolism , Sirtuin 1/biosynthesis , Sirtuins/biosynthesis , Animals , Body Weight/physiology , Cholesterol/blood , Energy Intake/physiology , Female , Ovarian Follicle/pathology , Rats , Rats, Sprague-Dawley , Sirtuin 1/metabolism , Sirtuins/metabolism , Triglycerides/blood
11.
Gen Comp Endocrinol ; 174(2): 232-7, 2011 Nov 01.
Article in English | MEDLINE | ID: mdl-21945120

ABSTRACT

The insulin-like growth factor-1 (IGF-1) plays an important role in the regulation of reproductive function. In the present study, we examined the effects of caloric restriction (CR) on the reproductive lifespan in rats and investigated the potential role of IGF-1. After 10 weeks of treatment, we determined the distribution of the ovarian follicles at various stages and measured the plasma level of IGF-1, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estrogen (ESG). Our results show that IGF-1 level was decreased after CR and correlated with the decrease in the levels of LH, FSH and ESG. Moreover, a higher percentage of primordial follicles and surviving follicles was observed in CR rats than in control rats (P<0.05). Immunohistochemical analysis showed that IGF-1 was extensively expressed in the cytoplasm of granulosa cells in the surviving follicles at different stages but not in the atretic follicles. Taken together, these results suggest that caloric restriction promotes the reproductive capacity of female rats via modulating the level of IGF-1, which then regulate pituitary gonadotrope cells to reduce the release of LH, FSH and ESG, and modulate follicular development.


Subject(s)
Caloric Restriction , Insulin-Like Growth Factor I/metabolism , Animals , Estrogens/blood , Female , Follicle Stimulating Hormone/blood , Granulosa Cells/metabolism , Immunohistochemistry , Luteinizing Hormone/blood , Ovarian Follicle/physiology , Rats , Reproduction/physiology
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