E. Manickam - Academia.edu (original) (raw)

Papers by E. Manickam

Research paper thumbnail of Method design and validation for the determination of uranium levels in human urine using high-resolution alpha spectrometry

Journal of Environmental Radioactivity, 2008

Quantification of uranium in human urine is a valuable technique for assessing occupational and p... more Quantification of uranium in human urine is a valuable technique for assessing occupational and public exposure to uranium. A reliable method has been developed and validated in the ARPANSA Radiochemistry Laboratory by means of standard radiochemical separation and purification techniques and measurement using high-resolution alpha spectrometry. This method can be used to evaluate the levels of naturally occurring 234U, 235U and 238U in urine. Method design and validation is the process of defining an analytical requirement, and then confirming that the method under consideration has performance capabilities consistent with what the application requires. The method was designed to measure levels down to 2 mBq/day of total uranium, corresponding to approximately 1/100th of the annual committed effective dose of 20 mSv. Validation tests were developed to assess selectivity, accuracy, recovery and quantification of uncertainty. The radiochemical recovery of this method was measured using (232)U tracer. The typical minimum detectable concentration for total uranium for 24-h urine samples is approximately 0.6 mBq/day or 0.019 microg/day.

Research paper thumbnail of Identification and characterization of Snapin as a ubiquitously expressed SNARE-binding protein that interacts with SNAP23 in non-neuronal cells

Biochemical Journal, 2003

Members of the SNARE (soluble N-ethylmaleimide-sensitive fusion protein attachment protein recept... more Members of the SNARE (soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor) superfamily [syntaxins, VAMPs (vesicle-associated membrane proteins) and SNAP25 (synaptosome-associated protein-25)-related proteins] are required for intracellular membrane-fusion events in eukaryotes. In neurons, assembly of SNARE core complexes comprising the presynaptic membrane-associated SNAREs syntaxin 1 and SNAP25, and the vesicle-associated SNARE VAMP2, is necessary for synaptic vesicle exocytosis. Several accessory factors have been described that associate with the synaptic SNAREs and modulate core complex assembly or mediate Ca 2+ regulation. One such factor, Snapin, has been reported to be a brain-specific protein that interacts with SNAP25, and regulates association of the putative Ca 2+ -sensor synaptotagmin with the synaptic SNARE complex [Ilardi, Mochida and Sheng (1999) Nat. Neurosci. 2, 119-124]. Here we demonstrate that Snapin is expressed ubiquitously in neuronal and non-neuronal cells. Furthermore, using protein-protein-interaction assays we show that Snapin interacts with SNAP23, the widely expressed homologue of SNAP25, and that the predicted C-terminal helical domain of Snapin contains the SNAP23-binding site. Subcellular localization experiments revealed that Snapin is a soluble protein that exists in both cytosolic and peripheral membrane-bound pools in adipocytes. Moreover, association of Snapin with the plasma membrane was detected in cells overexpressing a Snapin-green fluorescent protein fusion protein. Finally, we show that Snapin is able to form a ternary complex with SNAP23 and syntaxin 4, suggesting that it is a component of non-neuronal SNARE complexes. An important implication of our results is that Snapin is likely to perform a general role in SNARE-mediated vesicle fusion events in non-neuronal cells in addition to its participation in Ca 2+ -regulated neurosecretion.

Research paper thumbnail of The Nutritional And Antinutritional Composition Of Strobilanthes Crispus (L.) Bremek And Its Anticancer Effect During Hepatocarcinogenesis

... Yahaya, for whom she is indebted to. ... 172 D Reagents Preparation for Uridine Diphosphogluc... more ... Yahaya, for whom she is indebted to. ... 172 D Reagents Preparation for Uridine Diphosphoglucuronyl Transferase Assay (Vessey and Zakim, 1972) 173 E-1 Reagents Preparation for Alkaline Phosphatase Assay (Method I: Jahan and Butterworth, 1986) 174 ...

Research paper thumbnail of THE EFFECTS OF LONG CHAIN n-3 PUFAS ON GENE EXPRESSION

Research paper thumbnail of Angiotensin-converting enzyme inhibition reverses diet-induced obesity, insulin resistance and inflammation in C57BL/6J mice

International Journal of Obesity, 2011

Angiotensin-converting enzyme (ACE) inhibition can reduce the body weight of mice maintained on a... more Angiotensin-converting enzyme (ACE) inhibition can reduce the body weight of mice maintained on a high-fat diet. The current study examined the effect of the ACE inhibitor, captopril (CAP), on the reversal of diet-induced obesity (DIO), insulin resistance and inflammation in mice. DIO was produced in C57BL/6J male mice (n=30) by maintaining animals on a high-fat diet (w/w 21% fat) for 12 weeks. During the subsequent 12-week treatment period, the animals were allowed access to the high-fat diet and either water containing CAP (0.05 mg ml(-1)) or plain tap water (CON, control). From the first week of treatment, food intake and body weight decreased in CAP-treated mice compared with CON mice. Both peripheral insulin sensitivity and hepatic insulin sensitivity were improved in CAP-treated mice compared with CON mice. CAP-treated mice had decreased absolute and relative liver and epididymal fat weights compared with CON mice. CAP-treated mice had higher plasma adiponectin and lower plasma leptin levels than CON mice. Relative to CON mice, CAP-treated mice had reduced adipose and skeletal muscle monocyte chemoattractant protein 1 (MCP-1), adipose interleukin-6 (IL-6), toll-like receptor 4 (TLR4) and uncoupling protein 2 (UCP2) mRNA expressions. Furthermore, CAP-treated mice had increased peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), long chain acyl-CoA dehydrogenase (LCAD), hormone sensitive lipase (HSL) and decreased lipoprotein lipase (LPL) mRNA expressions in the liver. The results of the current study indicate that in mice with DIO, CAP treatment reduced food intake and body weight, improved insulin sensitivity and decreased the mRNA expression of markers of inflammation. Thus, CAP may be a viable treatment for obesity, insulin resistance and inflammation.

Research paper thumbnail of Identification and characterization of Snapin as a ubiquitously expressed SNARE-binding protein that interacts with SNAP23 in non-neuronal cells

Biochemical Journal, 2003

Members of the SNARE (soluble N-ethylmaleimide-sensitive fusion protein attachment protein recept... more Members of the SNARE (soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor) superfamily [syntaxins, VAMPs (vesicle-associated membrane proteins) and SNAP25 (synaptosome-associated protein-25)-related proteins] are required for intracellular membrane-fusion events in eukaryotes. In neurons, assembly of SNARE core complexes comprising the presynaptic membrane-associated SNAREs syntaxin 1a n dS N A P 25, and the vesicle-associated SNARE VAMP2, is necessary for synaptic vesicle exocytosis. Several accessory factors have been described that associate with the synaptic SNAREs and modulate core complex assembly or mediate Ca 2+ regulation. One such factor, Snapin, has been reported to be a brain-specific protein that interacts with SNAP25, and regulates association of the putative Ca 2+ -sensor synaptotagmin with the synaptic SNARE complex [Ilardi, Mochida and Sheng (1999) Nat. Neurosci. 2, 119-124]. Here we demonstrate that Snapin is expressed ubiquitously in neuronal and non-neuronal cells. Furthermore, using protein-protein-interaction assays we show that Snapin interacts with SNAP23, the widely expressed homologue of SNAP25, and that the predicted C-terminal helical domain of Snapin contains the SNAP23-binding site. Subcellular localization experiments revealed that Snapin is a soluble protein that exists in both cytosolic and peripheral membrane-bound pools in adipocytes. Moreover, association of Snapin with the plasma membrane was detected in cells overexpressing a Snapin-green fluorescent protein fusion protein. Finally, we show that Snapin is able to form a ternary complex with SNAP23 and syntaxin 4, suggesting that it is a component of non-neuronal SNARE complexes. An important implication of our results is that Snapin is likely to perform a general role in SNARE-mediated vesicle fusion events in non-neuronal cells in addition to its participation in Ca 2+ -regulated neurosecretion.

Research paper thumbnail of Fish oil replacement in rainbow trout diets and total dietary PUFA content: I) Effects on feed efficiency, fat deposition and the efficiency of a finishing strategy

Aquaculture, 2011

Fish oil replacement Alpha-linolenic acid (18:3n-3) Linoleic acid (18:2n-6) Desaturase Elongase

Research paper thumbnail of Method design and validation for the determination of uranium levels in human urine using high-resolution alpha spectrometry

Journal of Environmental Radioactivity, 2008

Quantification of uranium in human urine is a valuable technique for assessing occupational and p... more Quantification of uranium in human urine is a valuable technique for assessing occupational and public exposure to uranium. A reliable method has been developed and validated in the ARPANSA Radiochemistry Laboratory by means of standard radiochemical separation and purification techniques and measurement using high-resolution alpha spectrometry. This method can be used to evaluate the levels of naturally occurring 234U, 235U and 238U in urine. Method design and validation is the process of defining an analytical requirement, and then confirming that the method under consideration has performance capabilities consistent with what the application requires. The method was designed to measure levels down to 2 mBq/day of total uranium, corresponding to approximately 1/100th of the annual committed effective dose of 20 mSv. Validation tests were developed to assess selectivity, accuracy, recovery and quantification of uncertainty. The radiochemical recovery of this method was measured using (232)U tracer. The typical minimum detectable concentration for total uranium for 24-h urine samples is approximately 0.6 mBq/day or 0.019 microg/day.

Research paper thumbnail of Method design and validation for the determination of uranium levels in human urine using high-resolution alpha spectrometry

Journal of Environmental Radioactivity, 2008

Quantification of uranium in human urine is a valuable technique for assessing occupational and p... more Quantification of uranium in human urine is a valuable technique for assessing occupational and public exposure to uranium. A reliable method has been developed and validated in the ARPANSA Radiochemistry Laboratory by means of standard radiochemical separation and purification techniques and measurement using high-resolution alpha spectrometry. This method can be used to evaluate the levels of naturally occurring 234U, 235U and 238U in urine. Method design and validation is the process of defining an analytical requirement, and then confirming that the method under consideration has performance capabilities consistent with what the application requires. The method was designed to measure levels down to 2 mBq/day of total uranium, corresponding to approximately 1/100th of the annual committed effective dose of 20 mSv. Validation tests were developed to assess selectivity, accuracy, recovery and quantification of uncertainty. The radiochemical recovery of this method was measured using (232)U tracer. The typical minimum detectable concentration for total uranium for 24-h urine samples is approximately 0.6 mBq/day or 0.019 microg/day.

Research paper thumbnail of Identification and characterization of Snapin as a ubiquitously expressed SNARE-binding protein that interacts with SNAP23 in non-neuronal cells

Biochemical Journal, 2003

Members of the SNARE (soluble N-ethylmaleimide-sensitive fusion protein attachment protein recept... more Members of the SNARE (soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor) superfamily [syntaxins, VAMPs (vesicle-associated membrane proteins) and SNAP25 (synaptosome-associated protein-25)-related proteins] are required for intracellular membrane-fusion events in eukaryotes. In neurons, assembly of SNARE core complexes comprising the presynaptic membrane-associated SNAREs syntaxin 1 and SNAP25, and the vesicle-associated SNARE VAMP2, is necessary for synaptic vesicle exocytosis. Several accessory factors have been described that associate with the synaptic SNAREs and modulate core complex assembly or mediate Ca 2+ regulation. One such factor, Snapin, has been reported to be a brain-specific protein that interacts with SNAP25, and regulates association of the putative Ca 2+ -sensor synaptotagmin with the synaptic SNARE complex [Ilardi, Mochida and Sheng (1999) Nat. Neurosci. 2, 119-124]. Here we demonstrate that Snapin is expressed ubiquitously in neuronal and non-neuronal cells. Furthermore, using protein-protein-interaction assays we show that Snapin interacts with SNAP23, the widely expressed homologue of SNAP25, and that the predicted C-terminal helical domain of Snapin contains the SNAP23-binding site. Subcellular localization experiments revealed that Snapin is a soluble protein that exists in both cytosolic and peripheral membrane-bound pools in adipocytes. Moreover, association of Snapin with the plasma membrane was detected in cells overexpressing a Snapin-green fluorescent protein fusion protein. Finally, we show that Snapin is able to form a ternary complex with SNAP23 and syntaxin 4, suggesting that it is a component of non-neuronal SNARE complexes. An important implication of our results is that Snapin is likely to perform a general role in SNARE-mediated vesicle fusion events in non-neuronal cells in addition to its participation in Ca 2+ -regulated neurosecretion.

Research paper thumbnail of The Nutritional And Antinutritional Composition Of Strobilanthes Crispus (L.) Bremek And Its Anticancer Effect During Hepatocarcinogenesis

... Yahaya, for whom she is indebted to. ... 172 D Reagents Preparation for Uridine Diphosphogluc... more ... Yahaya, for whom she is indebted to. ... 172 D Reagents Preparation for Uridine Diphosphoglucuronyl Transferase Assay (Vessey and Zakim, 1972) 173 E-1 Reagents Preparation for Alkaline Phosphatase Assay (Method I: Jahan and Butterworth, 1986) 174 ...

Research paper thumbnail of THE EFFECTS OF LONG CHAIN n-3 PUFAS ON GENE EXPRESSION

Research paper thumbnail of Angiotensin-converting enzyme inhibition reverses diet-induced obesity, insulin resistance and inflammation in C57BL/6J mice

International Journal of Obesity, 2011

Angiotensin-converting enzyme (ACE) inhibition can reduce the body weight of mice maintained on a... more Angiotensin-converting enzyme (ACE) inhibition can reduce the body weight of mice maintained on a high-fat diet. The current study examined the effect of the ACE inhibitor, captopril (CAP), on the reversal of diet-induced obesity (DIO), insulin resistance and inflammation in mice. DIO was produced in C57BL/6J male mice (n=30) by maintaining animals on a high-fat diet (w/w 21% fat) for 12 weeks. During the subsequent 12-week treatment period, the animals were allowed access to the high-fat diet and either water containing CAP (0.05 mg ml(-1)) or plain tap water (CON, control). From the first week of treatment, food intake and body weight decreased in CAP-treated mice compared with CON mice. Both peripheral insulin sensitivity and hepatic insulin sensitivity were improved in CAP-treated mice compared with CON mice. CAP-treated mice had decreased absolute and relative liver and epididymal fat weights compared with CON mice. CAP-treated mice had higher plasma adiponectin and lower plasma leptin levels than CON mice. Relative to CON mice, CAP-treated mice had reduced adipose and skeletal muscle monocyte chemoattractant protein 1 (MCP-1), adipose interleukin-6 (IL-6), toll-like receptor 4 (TLR4) and uncoupling protein 2 (UCP2) mRNA expressions. Furthermore, CAP-treated mice had increased peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), long chain acyl-CoA dehydrogenase (LCAD), hormone sensitive lipase (HSL) and decreased lipoprotein lipase (LPL) mRNA expressions in the liver. The results of the current study indicate that in mice with DIO, CAP treatment reduced food intake and body weight, improved insulin sensitivity and decreased the mRNA expression of markers of inflammation. Thus, CAP may be a viable treatment for obesity, insulin resistance and inflammation.

Research paper thumbnail of Identification and characterization of Snapin as a ubiquitously expressed SNARE-binding protein that interacts with SNAP23 in non-neuronal cells

Biochemical Journal, 2003

Members of the SNARE (soluble N-ethylmaleimide-sensitive fusion protein attachment protein recept... more Members of the SNARE (soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor) superfamily [syntaxins, VAMPs (vesicle-associated membrane proteins) and SNAP25 (synaptosome-associated protein-25)-related proteins] are required for intracellular membrane-fusion events in eukaryotes. In neurons, assembly of SNARE core complexes comprising the presynaptic membrane-associated SNAREs syntaxin 1a n dS N A P 25, and the vesicle-associated SNARE VAMP2, is necessary for synaptic vesicle exocytosis. Several accessory factors have been described that associate with the synaptic SNAREs and modulate core complex assembly or mediate Ca 2+ regulation. One such factor, Snapin, has been reported to be a brain-specific protein that interacts with SNAP25, and regulates association of the putative Ca 2+ -sensor synaptotagmin with the synaptic SNARE complex [Ilardi, Mochida and Sheng (1999) Nat. Neurosci. 2, 119-124]. Here we demonstrate that Snapin is expressed ubiquitously in neuronal and non-neuronal cells. Furthermore, using protein-protein-interaction assays we show that Snapin interacts with SNAP23, the widely expressed homologue of SNAP25, and that the predicted C-terminal helical domain of Snapin contains the SNAP23-binding site. Subcellular localization experiments revealed that Snapin is a soluble protein that exists in both cytosolic and peripheral membrane-bound pools in adipocytes. Moreover, association of Snapin with the plasma membrane was detected in cells overexpressing a Snapin-green fluorescent protein fusion protein. Finally, we show that Snapin is able to form a ternary complex with SNAP23 and syntaxin 4, suggesting that it is a component of non-neuronal SNARE complexes. An important implication of our results is that Snapin is likely to perform a general role in SNARE-mediated vesicle fusion events in non-neuronal cells in addition to its participation in Ca 2+ -regulated neurosecretion.

Research paper thumbnail of Fish oil replacement in rainbow trout diets and total dietary PUFA content: I) Effects on feed efficiency, fat deposition and the efficiency of a finishing strategy

Aquaculture, 2011

Fish oil replacement Alpha-linolenic acid (18:3n-3) Linoleic acid (18:2n-6) Desaturase Elongase

Research paper thumbnail of Method design and validation for the determination of uranium levels in human urine using high-resolution alpha spectrometry

Journal of Environmental Radioactivity, 2008

Quantification of uranium in human urine is a valuable technique for assessing occupational and p... more Quantification of uranium in human urine is a valuable technique for assessing occupational and public exposure to uranium. A reliable method has been developed and validated in the ARPANSA Radiochemistry Laboratory by means of standard radiochemical separation and purification techniques and measurement using high-resolution alpha spectrometry. This method can be used to evaluate the levels of naturally occurring 234U, 235U and 238U in urine. Method design and validation is the process of defining an analytical requirement, and then confirming that the method under consideration has performance capabilities consistent with what the application requires. The method was designed to measure levels down to 2 mBq/day of total uranium, corresponding to approximately 1/100th of the annual committed effective dose of 20 mSv. Validation tests were developed to assess selectivity, accuracy, recovery and quantification of uncertainty. The radiochemical recovery of this method was measured using (232)U tracer. The typical minimum detectable concentration for total uranium for 24-h urine samples is approximately 0.6 mBq/day or 0.019 microg/day.