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1.
Talanta ; 107: 263-9, 2013 Mar 30.
Article in English | MEDLINE | ID: mdl-23598221

ABSTRACT

A novel selenium nanoparticles (Se NPs)-amplified chemiluminescence (CL) reaction, Se NPs-potassium permanganate-dinitrobutylphenol (DNBP), for the determination of DNBP at gram per milliliter level is described. In the present study, it was found that direct reaction of DNBP with potassium permanganate (KMnO4) in the acidic mediums elicited light emission, which was greatly enhanced by selenium nanoparticles. Under optimum conditions, the CL intensity is linearly related to the concentration of DNBP in the range of 1.0×10(-7)-8.0×10(-5)g mL(-1) with a detection limit (3σ) of 3.1×10(-8) g mL(-1). The relative standard deviation for 11 determinations of 2.5×10(-5) gm L(-1) DNBP is 2.07%. The Se NPs were prepared by the chemical hydrothermal method. It was found that catalytic properties of Se NPs were higher than those of microparticles (MPs). In addition, scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to characterize the Se NPs. Appropriate sensitivity, selectivity and precision were among notable features of the proposed method. The method was successfully applied to the determination of DNBP in the water samples of different origins. Moreover, the possible mechanism for the new CL reaction was also discussed.


Subject(s)
2,4-Dinitrophenol/analogs & derivatives , Luminescent Measurements/methods , Nanoparticles/chemistry , Pesticides/analysis , Selenium/chemistry , Water Pollutants, Chemical/analysis , 2,4-Dinitrophenol/analysis , Fresh Water/analysis , Limit of Detection , Luminescence , Nanoparticles/ultrastructure , Potassium Permanganate/chemistry
2.
J Food Sci ; 74(9): C653-7, 2009.
Article in English | MEDLINE | ID: mdl-20492097

ABSTRACT

The purpose of this study was to examine the effect of various fiber additions on lipid digestion during the in vitro digestion of beef patties. The control patties were prepared with 90.5% lean meat and 9.5% tallow. Treatments consisted of 90% lean meat with 9.5% tallow and either 0.5% cellulose, 0.5% chitosan, or 0.5% pectin. The beef patties were then passed through an in vitro digestion model that simulated the composition of the mouth, stomach, and small intestine juices. The change in structure and properties of the lipid droplets was monitored by laser scanning confocal fluorescence microscopy. In general, there was a decrease in lipid droplet diameter as the droplets moved from mouth to stomach to small intestine. The amount of free fatty acid dramatically increased after in vitro digestion in all beef patties. The amount of free fatty acid was, however, lower in beef patties containing chitosan and pectin than other beef patties after in vitro digestion. Beef patties containing various fibers had lower thiobarbituric acid-reactive substances (TBARS) values than samples with no fibers. Among the samples to which fibers were added, chitosan and pectin had lower TBARS than beef patties with cellulose. The cholesterol content decreased after in vitro digestion in all beef patties but was not different among the beef patties before and after in vitro digestion. These results enhance our understanding of the physicochemical and structural changes that occur to ground beef within the gastrointestinal tract.


Subject(s)
Dietary Fiber , Digestion , Lipid Metabolism , Meat Products/analysis , Animals , Cattle , Cellulose , Chitosan , Cholesterol/analysis , Fatty Acids, Nonesterified/analysis , Microscopy, Confocal , Pectins , Thiobarbituric Acid Reactive Substances/analysis
4.
Int J Impot Res ; 16(4): 350-3, 2004 Aug.
Article in English | MEDLINE | ID: mdl-14985780

ABSTRACT

The association between erectile dysfunction (ED) and acute myocardial infarction (AMI) among men was examined in the Integrated Healthcare Information Services National Managed Care Benchmark Database (IHCIS). The IHCIS is a fully de-identified, HIPAA-compliant database and includes complete medical history for more than 17 million managed care lives; data from more than 30 US health plans, covering seven census regions; and patient demographics, including morbidity, age and gender. A total of 12,825 ED patients and an equal number of male patients without ED were included in the retrospective cohort study. Logistic regression analyses were performed to assess the adjusted risk of AMI that accounted for age at ED diagnosis, smoking, obesity and medications including ACE inhibitors, beta blockers and statins. The cohort of men with ED were observed to have a two-fold increase in the risk for AMI (OR=1.99, 95% CI=1.17, 3.38) after adjusting for age at ED diagnosis, smoking, obesity, and use of ACE inhibitors, beta blockers and statins. Some evidence of a possible trend toward increased risk was detected by age group. After controlling for the aforementioned covariates and compared to men 30-39 y of age, it was noted that patients 40-44 y of age were 3.8 times more likely to develop an AMI (OR=3.76, 95% CI=1.21, 11.7), 45- to 49-y-old men were also more than three times as likely to have an AMI (OR=3.14, 95% CI=1.03, 9.64), and 50- to 55-y-old patients had a four-fold increased risk of developing AMI (OR=4.04, 95% CI=1.39, 11.7). The risk becomes more pronounced with increasing age, indicating the need for cardiologists and internists to monitor ED patients who may not necessarily present with cardiovascular symptoms.


Subject(s)
Erectile Dysfunction/epidemiology , Myocardial Infarction/epidemiology , Acute Disease , Adult , Biomarkers , Cohort Studies , Databases, Factual , Erectile Dysfunction/etiology , Humans , Logistic Models , Male , Middle Aged , Retrospective Studies , Risk Factors , Smoking/epidemiology
5.
Aging Male ; 6(4): 217-21, 2003 Dec.
Article in English | MEDLINE | ID: mdl-15006259

ABSTRACT

The association between erectile dysfunction (ED) and peripheral vascular disease (PVD) among men was examined in the Integrated Healthcare Information Services National Managed Care Benchmark Database (IHCIS). The IHCIS is a fully de-identified, Health Insurance Portability and Accountability Act compliant database and includes complete medical histories for more than 17 million managed-care lives; data from more than 30 US health plans, covering seven census regions; and patient demographics, including morbidity, age and gender. A total of 12 825 ED patients and an equal number of male patients without ED were included in the retrospective cohort study. Logistic regression analyses were performed to assess the adjusted risk of PVD that accounted for age at ED diagnosis, smoking, obesity and medications including angiotensin converting enzyme (ACE) inhibitors, beta blockers and statins. The cohort of men with ED were observed to have a 75% increase in risk for PVD (odds ratio (OR) = 1.75, 95% confidence interval (CI) = 1.06, 2.90) after adjusting for age at ED diagnosis, smoking, obesity and use of ACE inhibitors, beta blockers and statins. Some evidence of a possible trend towards increased risk was detected by age group. After controlling for the aforementioned covariates and compared to men aged 30-39 years, it was noted that patients aged 40-44 years were 2.1 times more likely to develop PVD (OR = 2.07, 95% CI = 0.89, 4.81), 45-49-year-old men were also more than twice as likely to have PVD (OR = 2.32, 95% CI = 1.03, 5.22), and 50-55-year-old patients had a three-fold increased risk of developing PVD (OR = 3.00, 95% CI = 1.40, 6.43). The results of this study indicate that ED may serve as a marker for PVD. The risk becomes more pronounced with increasing age, indicating the need for cardiologists and internists to monitor ED patients who may not necessarily present with cardiovascular symptoms.


Subject(s)
Erectile Dysfunction/complications , Peripheral Vascular Diseases/etiology , Adult , Erectile Dysfunction/epidemiology , Humans , Logistic Models , Male , Middle Aged , Peripheral Vascular Diseases/epidemiology , Retrospective Studies , Risk Factors , United States/epidemiology
6.
J Anim Sci ; 80(1): 108-12, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11831506

ABSTRACT

The effects of dietary conjugated linoleic acid (CLA) on fatty acid composition, lipid oxidation, and pork quality were investigated. Pigs (n = 20) were fed a diet containing 0, 1, 2.5, or 5% CLA for 4 wk and slaughtered at 105 kg. The longissimus thoracis et lumborum muscle was collected at 24 h postmortem. Pork loin chops (3 cm thick) were packaged aerobically and stored at 4 degrees C for 7 d. Samples were analyzed for ultimate pH, intramuscular fat content, fatty acid composition, thiobarbituric acid-reactive substances, color (L*, a*, b*), and water-holding capacity. Dietary CLA reduced the concentration of linoleic acid and increased CLA concentration in intramuscular fat of pork loin (P < 0.05). The concentration of CLA in muscle was increased with dietary CLA level and did not change during storage. Thiobarbituric acid-reactive substance value of control was higher than that of the CLA-fed groups (P < 0.05). Intramuscular fat content was increased by dietary CLA, and less purge loss was observed with samples from CLA-fed pigs (P < 0.05). Dietary CLA improved the color stability of pork loin during cold storage. After 7 d, lightness (L*) and yellowness (b*) of the 5% CLA-fed group were significantly lower than those of control (P < 0.05). The results indicated that the water-holding capacity of pork loin was increased with increased intramuscular fat content apparently caused by dietary CLA. Also, the data indicated that color stability of pork was improved with inhibition of lipid oxidation and changing of fatty acid composition by dietary CLA.


Subject(s)
Fatty Acids/analysis , Linoleic Acid/administration & dosage , Lipid Metabolism , Meat/standards , Swine/growth & development , Animals , Body Composition , Dietary Fats, Unsaturated/administration & dosage , Dietary Fats, Unsaturated/metabolism , Female , Food Handling/methods , Hydrogen-Ion Concentration , Linoleic Acid/metabolism , Meat/analysis , Oxidation-Reduction , Pigmentation , Swine/metabolism , Thiobarbituric Acid Reactive Substances/analysis
7.
Plant Mol Biol ; 41(4): 443-54, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10608655

ABSTRACT

Indole-3-acetic acid (IAA) markedly increased ethylene production by inducing the expression of three 1aminocyclopropane-1-carboxylate (ACC) synthase cDNAs (pVR-ACS1, pVR-ACS6 and pVR-ACS7) in mung bean hypocotyls. Results from nuclear run-on transcription assay and RNA gel blot studies revealed that all three genes were transcriptionally active displaying unique patterns of induction by IAA and various hormones in etiolated hypocotyls. Particularly, 24-epibrassinolide (BR), an active brassinosteroid, specifically enhanced the expression of VR-ACS7 by a distinct temporal induction mechanism compared to that of IAA. In addition, BR synergistically increased the IAA-induced VR-ACS6 and VR-ACS7 transcript levels, while it effectively abolished both the IAA- and kinetin-induced accumulation of VR-ACS1 mRNA. In light-grown plants, VR-ACS1 was induced by IAA in roots, and VR-ACS6 in epicotyls. IAA- and BR-treatments were not able to increase the VR-ACS7 transcript in the light-grown tissues. These results indicate that the expression of ACC synthase multigene family is regulated by complex hormonal and developmental networks in a gene- and tissue-specific manner in mung bean plants. The VR-ACS7 gene was isolated, and chimeric fusion between the 2.4 kb 5'-upstream region and the beta-glucuronidase (GUS) reporter gene was constructed and introduced into Nicotiana tabacum. Analysis of transgenic tobacco plants revealed the VR-ACS7 promoter-driven GUS activity at a highly localized region of the hypocotyl-root junction of control seedlings, while a marked induction of GUS activity was detected only in the hypocotyl region of the IAA-treated transgenic seedlings where rapid cell elongation occurs. Although there was a modest synergistic effect of BR on the IAA-induced GUS activity, BR alone failed to increase the GUS activity, suggesting that induction of VR-ACS7 occurs via separate signaling pathways in response to IAA and BR. A scheme of the multiple regulatory pathways for the expression of ACC synthase multigene family by auxin and BR is presented.


Subject(s)
Cholestanols/pharmacology , Fabaceae/drug effects , Indoleacetic Acids/pharmacology , Lyases/genetics , Multigene Family/genetics , Plants, Medicinal , Steroids, Heterocyclic/pharmacology , Brassinosteroids , DNA, Plant/genetics , DNA, Plant/isolation & purification , Ethylenes/biosynthesis , Fabaceae/enzymology , Fabaceae/genetics , Gene Expression Regulation, Enzymologic/drug effects , Gene Expression Regulation, Plant/drug effects , Genes, Plant/genetics , Glucuronidase/drug effects , Glucuronidase/genetics , Glucuronidase/metabolism , Isoenzymes/genetics , Molecular Sequence Data , Plant Growth Regulators/pharmacology , Plants, Genetically Modified , Plants, Toxic , Promoter Regions, Genetic/genetics , RNA, Messenger/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , Recombinant Fusion Proteins/drug effects , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Sensitivity and Specificity , Tissue Distribution , Nicotiana/drug effects , Nicotiana/genetics , Transcription, Genetic/drug effects
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