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1.
Biochem Mol Biol Educ ; 43(2): 121-5, 2015.
Article in English | MEDLINE | ID: mdl-25752808

ABSTRACT

Undergraduate laboratories expose students to a wide variety of topics and techniques in a limited amount of time. This can be a challenge and lead to less exposure to concepts and activities in bio-inorganic chemistry and analytical chemistry that are closely-related to biochemistry. To address this, we incorporated a new iron determination by atomic absorption spectroscopy exercise as part of a five-week long laboratory-based project on the purification of myoglobin from beef. Students were required to prepare samples for chemical analysis, operate an atomic absorption spectrophotometer, critically evaluate their iron data, and integrate these data into a study of myoglobin.


Subject(s)
Biochemistry/education , Chemistry, Analytic/education , Chemistry, Inorganic/education , Education, Special/methods , Humans
2.
Biochem Mol Biol Educ ; 43(1): 6-12, 2015.
Article in English | MEDLINE | ID: mdl-25395308

ABSTRACT

The use of internet-based technologies in the teaching of laboratories has emerged as a promising education tool. This study evaluated the effectiveness of using remote access technology to operate an atomic absorption spectrophotometer in analyzing the iron content in a crude myoglobin extract. Sixty-two students were surveyed on their level of engagement, learning, and overall experience. Feedback from students suggests that the use of remote access technology is effective in teaching students the principles of chemical analysis by atomic absorption spectroscopy.


Subject(s)
Computer-Assisted Instruction/methods , Education, Distance , Learning , Spectrophotometry, Atomic , Educational Technology/methods , Humans , Internet
3.
J Agric Food Chem ; 61(41): 9915-21, 2013 Oct 16.
Article in English | MEDLINE | ID: mdl-24099031

ABSTRACT

The application of (1)H nuclear magnetic resonance (NMR) spectroscopy to the measurement of conjugated linoleic acid (CLA) content in the lipid fraction of dairy products is both a novel and inviting alternative to traditional methods such as gas chromatography (GC), which can require time-consuming sample derivatization. In this work, a newly developed, rapid, and reliable lipid extraction protocol was combined with simple, nondestructive (1)H NMR spectroscopic analysis to measure the total CLA content in CLA standards and in various Canadian cheeses from conventional, organic, and grass-fed dairy sources. The total CLA concentrations (mg/g cheese) obtained using these new extraction and analysis methods were consistent with amounts found using the modified Folch extraction and GC analysis (correlation coefficient of 0.948). Results showed that cheeses from exclusively grass-fed dairy cows were significantly higher in total CLA content than either conventional or organic cheese.


Subject(s)
Cheese/analysis , Linoleic Acids, Conjugated/analysis , Magnetic Resonance Spectroscopy/methods , Animals , Canada , Cattle , Chromatography, Gas , Milk/chemistry
4.
J Sep Sci ; 36(20): 3440-8, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23943402

ABSTRACT

A lower dietary omega-6/omega-3 (n-6/n-3) fatty acid ratio (<4) has been shown to be beneficial in preventing a number of chronic illnesses. Interest exists in developing more rapid and sensitive analytical methods for profiling fatty acid levels in foods. An aqueous CE method was developed for the simultaneous determination of 15 n-3 and n-6 relevant fatty acids. The effect of pH and concentration of buffer, type and concentration of organic modifier, and additive on the separation was investigated in order to determine the best conditions for the analysis. Baseline separations of the 15 fatty acids were achieved using 40 mM borate buffer at pH 9.50 containing 50 mM SDS, 10 mM ß-cyclodextrin, and 10% acetonitrile. The developed CE method has LODs of <5 mg/L and good linearity (R(2) > 0.980) for all fatty acids studied. The proposed method was successfully applied to the determination of n-3 and n-6 fatty acids in flax seed, Udo® oils and a selection of grass-fed and grain-fed beef muscle samples.


Subject(s)
Electrophoresis, Capillary/methods , Fatty Acids, Omega-3/analysis , Fatty Acids, Omega-6/analysis , Flax/chemistry , Meat/analysis , Plant Oils/analysis , Animals , Cattle
5.
Cancer Chemother Pharmacol ; 61(3): 407-13, 2008 Mar.
Article in English | MEDLINE | ID: mdl-17440726

ABSTRACT

G(2) checkpoint inhibitors can force cells arrested in G(2) phase by DNA damage to enter mitosis. In this manner, several G(2) checkpoint inhibitors can enhance killing of cancer cells by ionizing radiation and DNA-damaging chemotherapeutic agents, particularly in cells lacking p53 function. All G(2) checkpoint inhibitors identified to date target protein phosphorylation by inhibiting checkpoint kinases or phosphatases. Using a phenotypic cell-based assay for G(2) checkpoint inhibitors, we have screened a large collection of plant extracts and identified Z-Cryptofolione and Cryptomoscatone D2 as highly efficacious inhibitors of the G(2) checkpoint. These compounds and related pyrones also inhibit nuclear export. Leptomycin B, a potent inhibitor of Crm1-mediated nuclear export, is also a very potent G(2) checkpoint inhibitor. These compounds possess a reactive Michael acceptor site and do not appear promising as a radiosensitizing agents because they are toxic to unirradiated cells at checkpoint inhibitory concentrations. Nevertheless, the results show that inhibition of nuclear export is an alternative to checkpoint kinase inhibition for abrogating the G(2) checkpoint and they should stimulate the search for less toxic nuclear export inhibitors.


Subject(s)
Cell Nucleus/metabolism , Cell Nucleus/radiation effects , Cryptocarya/metabolism , Cryptocarya/radiation effects , G2 Phase/radiation effects , Pyrones/metabolism , Cell Line, Tumor , Enzyme-Linked Immunosorbent Assay , Fatty Acids, Unsaturated/pharmacology , Gamma Rays , Genes, Reporter/genetics , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , HIV Reverse Transcriptase/genetics , HIV Reverse Transcriptase/metabolism , Humans , Karyopherins/physiology , Plant Extracts/pharmacology , Receptors, Cytoplasmic and Nuclear/physiology , Exportin 1 Protein
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