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1.
Sci Total Environ ; 599-600: 2142-2155, 2017 Dec 01.
Article in English | MEDLINE | ID: mdl-28575929

ABSTRACT

Mitigating for the negative impacts of stormwater runoff is becoming a concern due to increased land development. Understanding how land development influences stormwater runoff is essential for sustainably managing water resources. In recent years, aggregate low impact development-best management practices (LID-BMPs) have been implemented to reduce the negative impacts of stormwater runoff on receiving water bodies. This study used an integrated approach to determine the influence of land development and assess the ecological benefits of four aggregate LID-BMPs in stormwater runoff from a mixed land use and land cover (LULC) catchment with ongoing land development. It used data from 2011 to 2015 that monitored 41 storm events and monthly LULC, and a Personalized Computer Storm Water Management Model (PCSWMM). The four aggregate LID-BMPs are: ecological (S1), utilizing pervious covers (S2), and multi-control (S3) and (S4). These LID-BMPs were designed and distributed in the study area based on catchment characteristics, cost, and effectiveness. PCSWMM was used to simulate the monitored storm events from 2014 (calibration: R2 and NSE>0.5; RMSE <11) and 2015 (validation: R2 and NSE>0.5; RMSE <12). For continuous simulation and analyzing LID-BMPs scenarios, the five-year (2011 to 2015) stormwater runoff data and LULC change patterns (only 2015 for LID-BMPs) were used. Results show that the expansion of bare land and impervious cover, soil alteration, and high amount of precipitation influenced the stormwater runoff variability during different phases of land development. The four aggregate LID-BMPs reduced runoff volume (34%-61%), peak flow (6%-19%), and pollutant concentrations (53%-83%). The results of this study, in addition to supporting local LULC planning and land development activities, also could be applied to input data for empirical modeling, and designing sustainable stormwater management guidelines and monitoring strategies.

2.
Sci Total Environ ; 550: 1171-1181, 2016 Apr 15.
Article in English | MEDLINE | ID: mdl-26895037

ABSTRACT

While the urban runoff are increasingly being studied as a source of fecal indicator bacteria (FIB), less is known about the occurrence of FIB in watershed with mixed land use and ongoing land use and land cover (LULC) change. In this study, Escherichia coli (EC) and fecal streptococcus (FS) were monitored from 2012 to 2013 in agricultural, mixed and urban LULC and analyzed according to the most probable number (MPN). Pearson correlation was used to determine the relationship between FIB and environmental parameters (physicochemical and hydrometeorological). Multiple linear regressions (MLR) were used to identify the significant parameters that affect the FIB concentrations and to predict the response of FIB in LULC change. Overall, the FIB concentrations were higher in urban LULC (EC=3.33-7.39; FS=3.30-7.36log10MPN/100mL) possibly because of runoff from commercial market and 100% impervious cover (IC). Also, during early-summer season; this reflects a greater persistence and growth rate of FIB in a warmer environment. During intra-event, however, the FIB concentrations varied according to site condition. Anthropogenic activities and IC influenced the correlation between the FIB concentrations and environmental parameters. Stormwater temperature (TEMP), turbidity, and TSS positively correlated with the FIB concentrations (p>0.01), since IC increased, implying an accumulation of bacterial sources in urban activities. TEMP, BOD5, turbidity, TSS, and antecedent dry days (ADD) were the most significant explanatory variables for FIB as determined in MLR, possibly because they promoted the FIB growth and survival. The model confirmed the FIB concentrations: EC (R(2)=0.71-0.85; NSE=0.72-0.86) and FS (R(2)=0.65-0.83; NSE=0.66-0.84) are predicted to increase due to urbanization. Therefore, these findings will help in stormwater monitoring strategies, designing the best management practice for FIB removal and as input data for stormwater models.


Subject(s)
Agriculture , Environmental Monitoring , Models, Theoretical , Water Microbiology , Rain , Water Movements
3.
Water Sci Technol ; 70(2): 218-25, 2014.
Article in English | MEDLINE | ID: mdl-25051467

ABSTRACT

Stormwater runoff quality is sensitive to land use and land cover (LULC) change. It is difficult to understand their relationship in predicting the pollution potential and developing watershed management practices to eliminate or reduce the pollution risk. In this study, the relationship between LULC change and stormwater runoff quality in two separate monitoring sites comprising a construction area (Site 1) and mixed land use (Site 2) was analyzed using geographic information system (GIS), event mean concentration (EMC), and correlation analysis. It was detected that bare land area increased, while other land use areas such as agriculture, commercial, forest, grassland, parking lot, residential, and road reduced. Based on the analyses performed, high maximum range and average EMCs were found in Site 2 for most of the water pollutants. Also, urban areas and increased conversion of LULC into bare land corresponded to degradation of stormwater quality. Correlation analysis between LULC and stormwater quality showed the influence of different factors such as farming practices, geographical location, and amount of precipitation, vegetation loss, and anthropogenic activities in monitoring sites. This research found that GIS application was an efficient tool for monthly monitoring, validation and statistical analysis of LULC change in the study area.


Subject(s)
Agriculture , Environmental Monitoring/methods , Rain , Water Movements , Water Pollutants, Chemical/chemistry , Geographic Information Systems , Republic of Korea
4.
J Neural Transm Suppl ; (71): 229-36, 2006.
Article in English | MEDLINE | ID: mdl-17447433

ABSTRACT

We have quantitated CSF and serum levels of Selenium, iron, copper and zinc by Atomic absorption spectrophotometer in 36 patients with parkinson's disease all on L-dopa therapy. Out of these 19 showed on or positive response to L-dopa where as 21 patients showed on and off response. These data were compared with 21 healthy controls. The results showed that serum levels of iron, copper and zinc remained unchanged where as in CSF, significant decrease in zinc was found in both on and on/off PD patients indicating the deficiency of zinc which continues in the worsening clinical condition of off patients. The level of copper remained unchanged in both on and on/off PD patients. Iron and selenium increase in CSF of both patients which is a clear evidence of relationship between increased iron and selenium level in brain which could be correlated with decrease in dopamine levels and oxidative stress in PD Patients.


Subject(s)
Metals, Heavy/blood , Metals, Heavy/cerebrospinal fluid , Parkinson Disease/blood , Parkinson Disease/cerebrospinal fluid , Selenium/blood , Selenium/cerebrospinal fluid , Aged , Analysis of Variance , Antiparkinson Agents/therapeutic use , Case-Control Studies , Copper , Female , Humans , Iron , Levodopa/therapeutic use , Male , Middle Aged , Parkinson Disease/drug therapy , Spectrophotometry, Atomic/methods , Zinc
5.
J Immunol ; 160(5): 2046-9, 1998 Mar 01.
Article in English | MEDLINE | ID: mdl-9498739

ABSTRACT

Current models for Fas (CD95)-mediated apoptosis suggest that FLICE/caspase-8 is recruited and activated, which results in cell death. However, the role of additional molecules in Fas signaling and FLICE activation is not clear. A chimeric Fas/FLICE (F/F) receptor, containing the extracellular/transmembrane portion of Fas and the caspase region of FLICE, mediated anti-Fas apoptosis. FLICE protease subunits were generated from the F/F precursor. Killing induced by Fas, but not F/F, was blocked by a dominant negative FADD. Apoptosis triggered through Fas and F/F was inhibited by coexpression of CrmA and p35, but not Bcl-xL. F/F bypassed Fas resistance in COS-7 cells and blocking by the death effector domain (DED)-containing viral protein MC159. These results show that: 1) F/F induces cell death, indicating that FLICE activation is sufficient for apoptosis and does not require additional Fas- or FADD-binding proteins; and 2) F/F bypasses proximal defects in Fas signaling that prevent FLICE recruitment or activation.


Subject(s)
Adaptor Proteins, Signal Transducing , Apoptosis/immunology , Carrier Proteins/metabolism , Caspases , Cysteine Endopeptidases/genetics , Membrane Glycoproteins/genetics , Recombinant Fusion Proteins/immunology , fas Receptor/genetics , Animals , Apoptosis/genetics , COS Cells , Carrier Proteins/genetics , Carrier Proteins/physiology , Caspase 8 , Caspase 9 , Cell Line , Cysteine Endopeptidases/physiology , Cytotoxicity, Immunologic , Fas Ligand Protein , Fas-Associated Death Domain Protein , Genes, Dominant/immunology , Hybridomas , Inhibitor of Apoptosis Proteins , Leukemia L1210 , Ligands , Membrane Glycoproteins/physiology , Mice , Proto-Oncogene Proteins c-bcl-2/physiology , Recombinant Fusion Proteins/chemical synthesis , Recombinant Fusion Proteins/physiology , Serpins/physiology , T-Lymphocytes , Viral Proteins/physiology , bcl-X Protein , fas Receptor/metabolism
6.
J Chromatogr B Biomed Sci Appl ; 693(1): 175-9, 1997 May 23.
Article in English | MEDLINE | ID: mdl-9200532

ABSTRACT

An high-performance liquid chromatographic (HPLC) method has been developed for the determination of cisplatin, based on precolumn derivatization of platinum(II) with bis(salicylaldehyde)tetramethylethylenediimine, extraction in chloroform and elution from a 3 microm Hypersil ODS column with methanol-acetonitrile-water as mobile phase and detection at 254 nm. Copper(II), iron(II), nickel(II), palladium(II), dioxouranium(IV) separated completely and did not affect the determination of platinum(II). The method was applied for the determination of cisplatin as platinum(II) in a pharmaceutical preparation and in blood samples of cancer patients after infusion of cisplatin.


Subject(s)
Antineoplastic Agents/analysis , Cisplatin/analysis , Organoplatinum Compounds , Platinum/analysis , Antineoplastic Agents/blood , Chromatography, High Pressure Liquid , Cisplatin/blood , Dosage Forms , Humans , Indicators and Reagents , Neoplasms/blood , Platinum/blood , Spectrophotometry, Ultraviolet
7.
J Immunol ; 157(9): 3845-9, 1996 Nov 01.
Article in English | MEDLINE | ID: mdl-8892614

ABSTRACT

Fas-mediated apoptosis plays an important role in regulating the immune response in peripheral T cells. Restimulation of T cell blasts up-regulates Fas and Fas ligand expression, with subsequent interaction leading to cell death. Overexpression of Bcl-2 in tumor cells blocks apoptosis induced by many stimuli, but inhibition of Fas-mediated killing has not been consistently observed. To examine the behavior of Bcl-2 in normal cells, T cell blasts were transiently transfected with Bcl-2 and related gene products to determine the effect on apoptotic signaling. Transient overexpression of Bcl-2 in mouse and human T cell blasts did not block Fas-mediated apoptosis, whereas etoposide- and glucocorticoid-induced cytotoxicity was potently inhibited. Expression of Bcl-xL and adenovirus E1B 19K did not interfere with anti-Fas killing. In contrast, interleukin-1beta-converting enzyme family protease inhibitors Ac-DEVD-CHO and CrmA blocked Fas-mediated apoptosis. These results suggest that peripheral T cells use distinct apoptosis signaling pathways with differential sensitivity to Bcl-2 and interleukin-1beta-converting enzyme family protease inhibitors. Since T cells normally express Bcl-2 and Bcl-xL following activation, their inability to block Fas-mediated apoptosis may allow for the elimination of self-reactive cells and the appropriate regulation of immune responses.


Subject(s)
Apoptosis/physiology , Cysteine Endopeptidases/physiology , Dexamethasone/pharmacology , Membrane Glycoproteins/physiology , Oligopeptides/pharmacology , Protease Inhibitors/pharmacology , Proto-Oncogene Proteins c-bcl-2/physiology , Signal Transduction/physiology , T-Lymphocytes, Cytotoxic/cytology , fas Receptor/physiology , Adenovirus E1B Proteins/biosynthesis , Adenovirus E1B Proteins/genetics , Animals , Apoptosis/drug effects , Caspase 1 , Cytotoxicity, Immunologic/drug effects , Etoposide/pharmacology , Fas Ligand Protein , Gene Expression Regulation , Humans , Hybridomas/cytology , Hybridomas/drug effects , Hybridomas/metabolism , Ionomycin/pharmacology , Ionophores/pharmacology , Lymphocyte Activation , Membrane Glycoproteins/genetics , Mice , Mice, Inbred BALB C , Proto-Oncogene Proteins/biosynthesis , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins c-bcl-2/genetics , Recombinant Fusion Proteins/biosynthesis , Signal Transduction/drug effects , T-Lymphocytes, Cytotoxic/drug effects , T-Lymphocytes, Cytotoxic/metabolism , Tetradecanoylphorbol Acetate/pharmacology , Transfection , bcl-X Protein , fas Receptor/genetics
8.
J Immunol ; 155(10): 4644-52, 1995 Nov 15.
Article in English | MEDLINE | ID: mdl-7594463

ABSTRACT

Overexpression of Bcl-2 can prevent or markedly delay cell death induced by a variety of apoptotic stimuli. Although Fas and Fas ligand (FasL) interactions play a major role in the elimination of self-reactive T cells in the periphery, inhibition of Fas-mediated killing by Bcl-2 has not been consistently observed. The mouse T hybridoma 2B4.11 (2B4) has been a useful model to study glucocorticoid- and activation-induced apoptosis, which is mediated through Fas and FasL. Using both stable transfectants and transient transfections, overexpression of Bcl-2 or Bcl-xL readily blocked glucocorticoid-induced but not activation-induced apoptosis of 2B4 cells. Bcl-2 expression did not inhibit Fas-mediated cytotoxicity triggered by cells expressing FasL or by the transient transfection of human Fas. Similarly, overexpression of Bcl-2 in the mouse T hybridoma A1.1 did not block activation-induced/Fas-mediated apoptosis. In Jurkat cells, however, expression of Bcl-2 partially inhibited anti-Fas-induced cell death. A Bcl-2-related protein that can interfere with anti-Fas killing, the adenoviral E1B 19K, also did not block activation-induced/Fas-mediated apoptosis in 2B4 cells. In contrast, expression of CrmA, a cowpox virus protein that inhibits ICE-like protease activity, blocked activation-induced apoptosis in 2B4 cells but had little effect on Dex-mediated cytotoxicity. These results show that: 1) Bcl-2 can have strikingly different anti-cell death activity in the same cell depending upon the apoptotic stimulus, 2) distinct apoptosis signaling pathways may exist with differential sensitivity to Bcl-2 and ICE-like protease inhibitors.


Subject(s)
Apoptosis/immunology , Glucocorticoids/pharmacology , Hybridomas/immunology , Proto-Oncogene Proteins/biosynthesis , T-Lymphocytes/immunology , fas Receptor/immunology , Animals , Apoptosis/drug effects , Cytotoxicity, Immunologic , Humans , Lymphocyte Activation , Mice , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins c-bcl-2 , Transfection , bcl-X Protein
9.
J Immunol Methods ; 180(1): 15-24, 1995 Mar 13.
Article in English | MEDLINE | ID: mdl-7897244

ABSTRACT

Programmed cell death (PCD) has been observed in a wide variety of cell types in response to physiologic signals or types of stress. How these stimuli trigger PCD, and whether there is a common PCD signal transduction pathway, is not clear. As more genes are described that may participate in or regulate PCD, an assay system in which gene products can easily be introduced and/or modulated would be of great value. To avoid the generation and screening of multiple individual stable cell transfectants, a simple transient transfection death assay has been developed. 2B4.11, a murine T cell hybridoma, was transfected by electroporation with a constitutively active beta-galactosidase reporter gene and the cells were incubated in culture medium or with a PCD-inducing stimulus. The amount of beta-galactosidase activity remaining in the intact cells at the end of the culture period represented only viable transfected cells. Bcl-2 was chosen to examine whether this system would be useful to study the effect of transiently transfected genes since it blocks PCD in a number of experimental systems. Consistent with data obtained using stable transfectants, transient expression of Bcl-2 in 2B4.11 completely protected cells from glucocorticoid- and cytotoxic agent-induced PCD. This protection from death was confirmed at the individual cell level by the transient co-expression of a class I Ld surface antigen and flow cytometric analysis. Some of the advantages of the transient transfection death assay described here are; (1) the simple and sensitive beta-galactosidase assay, (2) the rapidity of the assay, (3) the ability to perform conventional viability assays to monitor treatment-induced cytotoxicity, (4) multiple gene products can be tested alone, and in combination, (5) antisense or dominant negative approaches can be used, and (6) the adaptability of this assay system to other cell types, transfection techniques, or reporter and expression vectors. The transient transfection death assay should make it easier to identify and order important steps in the PCD signal transduction pathways.


Subject(s)
Apoptosis/physiology , Proto-Oncogene Proteins/physiology , beta-Galactosidase/analysis , Animals , Cell Line , Cells, Cultured , Flow Cytometry , Gene Expression , Genes, Reporter , Hybridomas , Mice , Plasmids , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins c-bcl-2 , Signal Transduction , T-Lymphocytes/physiology , Transfection/genetics , beta-Galactosidase/genetics
10.
J Immunol ; 153(5): 2046-51, 1994 Sep 01.
Article in English | MEDLINE | ID: mdl-8051409

ABSTRACT

Expression of the transcription complex AP-1, composed of Jun and Fos family members, can be induced by a variety of stimuli. In lymphocytes, AP-1 transcriptional activity increases after TCR ligation and plays an important role in T cell activation events such as lymphokine secretion. To explore the requirements for AP-1 in IL-2 production, the AP-1 complex was targeted with a dominant negative mutant c-Jun protein, TAM-67, from which the transactivation domain has been deleted. In transient transfections of Jurkat cells, TAM-67 efficiently inhibited endogenous AP-1 transcriptional activity and blocked the activity of a reporter construct containing the 5' regulatory region of the IL-2 gene. TAM-67 also inhibited the transcriptional activity of nuclear factor-AT (NF-AT), whereas the NF-kappa B, NF-IL-2A, and the proximal TRE-like sites were relatively unaffected. The use of this dominant negative transcription factor suggests that: 1) transactivation-defective nuclear factors represent a novel approach to study the functional consequences of nuclear protein interactions on gene transcription; 2) the proximal TRE-like site from the IL-2 promoter is different from the consensus TRE; and 3) AP-1 plays an important role in the transcriptional activation mediated by the NF-AT binding complex.


Subject(s)
DNA-Binding Proteins/physiology , Genes, jun , Interleukin-2/genetics , Nuclear Proteins , Proto-Oncogene Proteins c-jun/physiology , Transcription Factors/physiology , Base Sequence , DNA Primers/chemistry , Gene Expression Regulation , Genes, Dominant , Molecular Sequence Data , NF-kappa B/physiology , NFATC Transcription Factors , RNA, Messenger/genetics , Regulatory Sequences, Nucleic Acid , Transcription, Genetic
11.
Talanta ; 33(2): 173-5, 1986 Feb.
Article in English | MEDLINE | ID: mdl-18964057

ABSTRACT

A simple and rapid method is described for the direct thermometric determination of milligram amounts of methyl dopa, propranolol hydrochloride, 1-phenyl-3-methylpyrazolone (MPP) and 2,3-dimethyl-1-phenylpyrazol-5-one (phenazone) in the presence of excipients. The compounds are reacted with N'-bromosuccinimide and the heat of reaction is used to determine the end-point of the titration. The time required is approximately 2 min, and the accuracy is analytically acceptable.

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