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Carmen Gagnon - One of the best experts on this subject based on the ideXlab platform.
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Fetal Hemoglobin Synthesis Determined by -mRNA/-mRNA -mRNA Quantitation in Infants at Risk for Sudden Infant Death Syndrome Being Monitored at Home for Apnea
2015Co-Authors: Carmen GagnonAbstract:ABSTRACT. Objective. Fetal hemoglobin (HbF) lev-els in the hemolysates obtained from infants who died from sudden infant death syndrome (SIDS) are reported to be markedly increased compared with controls. This finding could have been explained by increased HbF synthesis caused by episodes of hypoxemia in the SIDS infants. A prospective study in a group of infants being monitored at home after an apparent life-threatening event (ALTE) and considered at increased risk for SIDS was conducted with an improved Ribonuclease Protection Assay. The Ribonuclease Protection Assay allowed for the quantitation of [/()]-globin mRNAs, which has a highly significant correlation with the levels of HbF syn-thesis. Methods. Thirty-five infants who were admitted for an ALTE were included in the study. All infants were at home under surveillance with a cardiorespiratory moni-tor and followed in an apnea clinic with monthly ap-pointments. Seventy-three blood samples were obtained between 38 and 61 weeks of postconceptional age. For control purposes, a similar group of 37 normal infants (99 samples) whose HbF synthesis was previously deter-mined were included. Results. Mean [/()]-globin mRNAs were in-creased in the ALTE group at 42 to 45 and 46 to 49 weeks of postconceptional age (mean: 55.2 17.4 % and 33.9 14%) in comparison with HbF synthesis in controls (mean: 42.6 13.7 % and 23.6 9.8%). Conclusions. The data obtained in this report from infants who were considered at risk for SIDS show that HbF synthesis is increased between 42 and 49 weeks of postconceptional age. Determining HbF synthesis as de-scribed in this study may have value as a marker for episodes of hypoxemia for certain infants who are at risk for SIDS. Pediatrics 2003;112:e285–e288
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Fetal Hemoglobin Synthesis Determined by γ-mRNA/γ-mRNA + β-mRNA Quantitation in Infants at Risk for Sudden Infant Death Syndrome Being Monitored at Home for Apnea
Pediatrics, 2003Co-Authors: Harry Bard, Aurore Côté, Jean-paul Praud, Claire Infante-rivard, Carmen GagnonAbstract:Objective. Fetal hemoglobin (HbF) levels in the hemolysates obtained from infants who died from sudden infant death syndrome (SIDS) are reported to be markedly increased compared with controls. This finding could have been explained by increased HbF synthesis caused by episodes of hypoxemia in the SIDS infants. A prospective study in a group of infants being monitored at home after an apparent life-threatening event (ALTE) and considered at increased risk for SIDS was conducted with an improved Ribonuclease Protection Assay. The Ribonuclease Protection Assay allowed for the quantitation of [γ/(γ+β)]-globin mRNAs, which has a highly significant correlation with the levels of HbF synthesis. Methods. Thirty-five infants who were admitted for an ALTE were included in the study. All infants were at home under surveillance with a cardiorespiratory monitor and followed in an apnea clinic with monthly appointments. Seventy-three blood samples were obtained between 38 and 61 weeks of postconceptional age. For control purposes, a similar group of 37 normal infants (99 samples) whose HbF synthesis was previously determined were included. Results. Mean [γ/(γ+β)]-globin mRNAs were increased in the ALTE group at 42 to 45 and 46 to 49 weeks of postconceptional age (mean: 55.2 ± 17.4% and 33.9 ± 14%) in comparison with HbF synthesis in controls (mean: 42.6 ± 13.7% and 23.6 ± 9.8%). Conclusions. The data obtained in this report from infants who were considered at risk for SIDS show that HbF synthesis is increased between 42 and 49 weeks of postconceptional age. Determining HbF synthesis as described in this study may have value as a marker for episodes of hypoxemia for certain infants who are at risk for SIDS.
R R Buras - One of the best experts on this subject based on the ideXlab platform.
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Modulation of vitamin D receptor and estrogen receptor by 1,25(OH)2-vitamin D3 in T-47D human breast cancer cells.
The Journal of Steroid Biochemistry and Molecular Biology, 1995Co-Authors: F Davoodi, R V Brenner, S R Evans, L M Schumaker, M Shabahang, R J Nauta, R R BurasAbstract:Abstract 1,25(OH) 2 -Vitamin D 3 inhibits breast cancer cell proliferation through interaction with the vitamin D receptor (VDR). Regulation of VDR is under the influence of several factors which include the functional ligand for this receptor (1,25(OH) 2 -vitamin D 3 ) as well as heterologous steroid hormones. We evaluated the nature of homologous regulation in T-47D human breast cancer cells with a radiolabelled ligand binding Assay and a Ribonuclease Protection Assay for VDR. Significant VDR up-regulation, as measured by hormone binding Assays, occurred with pre-incubations with 10 −9 M through 10 −6 M 1,25(OH) 2 -vitamin D 3 ( P −8 M 1,25(OH) 2 -vitamin D 3 occurred at 4 h treatment and was not associated with an increase in VDR mRNA expression on Ribonuclease Protection Assay. This supports the hypothesis that up-regulation of VDR is probably the result of ligand-induced stabilization of pre-existing receptor. All- trans -retinoic acid, the progesterone analog R-5020, and prednisone were found to induce heterologous up-regulation of the VDR. We then determined with ligand binding Assays whether 1,25(OH) 2 -vitamin D 3 could influence receptor levels for another hormone in a manner analogous to the heterologous regulation of VDR. Regulation of estrogen receptor (ER) by 1,25(OH) 2 -vitamin D 3 was studied in T-47D and MDA-MB-231 breast cancer cells. Incubation of T-47D cells, which are ER (+), with 10 −8 M 1,25(OH) 2 -vitamin D 3 did not result in up-regulation of ER. Yet estrogen binding was significantly up-regulated in a cell line that is ER (−), MDA-MB-231. The increased estrogen binding was associated with a shift in binding affinity and Ribonuclease Protection Assay showed absence of ER mRNA in these cells, suggesting an up-regulation of estrogen binding proteins and not of the ER itself.
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Modulation of vitamin D receptor and estrogen receptor by 1,25(OH)2-vitamin D3 in T-47D human breast cancer cells.
The Journal of steroid biochemistry and molecular biology, 1995Co-Authors: F Davoodi, R V Brenner, S R Evans, L M Schumaker, M Shabahang, R J Nauta, R R BurasAbstract:1,25(OH)2-Vitamin D3 inhibits breast cancer cell proliferation through interaction with the vitamin D receptor (VDR). Regulation of VDR is under the influence of several factors which include the functional ligand for this receptor (1,25(OH)2-vitamin D3) as well as heterologous steroid hormones. We evaluated the nature of homologous regulation in T-47D human breast cancer cells with a radiolabelled ligand binding Assay and a Ribonuclease Protection Assay for VDR. Significant VDR up-regulation, as measured by hormone binding Assays, occurred with pre-incubations with 10(-9)M through 10(-6)M 1,25(OH)2-vitamin D3 (P < 0.05). A 7-fold VDR up-regulation with 10(-8)M 1,25(OH)2-vitamin D3 occurred at 4 h treatment and was not associated with an increase in VDR mRNA expression on Ribonuclease Protection Assay. This supports the hypothesis that up-regulation of VDR is probably the result of ligand-induced stabilization of pre-existing receptor. All-trans-retinoic acid, the progesterone analog R-5020, and prednisone were found to induce heterologous up-regulation of the VDR. We then determined with ligand binding Assays whether 1,25(OH)2-vitamin D3 could influence receptor levels for another hormone in a manner analogous to the heterologous regulation of VDR. Regulation of estrogen receptor (ER) by 1,25(OH)2-vitamin D3 was studied in T-47D and MDA-MB-231 breast cancer cells. Incubation of T-47D cells, which are ER (+), with 10(-8)M 1,25(OH)2-vitamin D3 did not result in up-regulation of ER. Yet estrogen binding was significantly up-regulated in a cell line that is ER(-), MDA-MB-231. The increased estrogen binding was associated with a shift in binding affinity and Ribonuclease Protection Assay showed absence of ER mRNA in these cells, suggesting an up-regulation of estrogen binding proteins and not of the ER itself.
Ganesan Vadamalai - One of the best experts on this subject based on the ideXlab platform.
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Chapter 34 – Gel Electrophoresis
Viroids and Satellites, 2017Co-Authors: D. Hanold, Ganesan VadamalaiAbstract:Gel electrophoresis (GE) is a versatile tool for research on viroids and other small circular nucleic acids. GE systems can be adapted to suit specific applications by adjusting variables of matrix and running conditions. Since sequence information is not required, GE is suitable for identifying that a viroid is associated with a disease of unknown etiology and for characterization of new viroids or viroid variants. For routine viroid diagnosis, sensitive, reliable, and robust systems can be designed. If sequence information and specific probes are available, GE can be combined with either gel-blotting to increase specificity and sensitivity of detection, or Ribonuclease Protection Assay to analyze populations of viroid variants and quasispecies.
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detection of coconut cadang cadang viroid sequences in oil and coconut palm by Ribonuclease Protection Assay
Annals of Applied Biology, 2009Co-Authors: Ganesan Vadamalai, A.a.f.l.k. Perera, D. Hanold, M. A. Rezaian, John W. RandlesAbstract:A Ribonuclease Protection Assay (RPA) has been developed for detecting Coconut cadang-cadang viroid (CCCVd) sequences. An RNA probe complementary to full-length CCCVd246 was used, terminating at nucleotide 65 in the upper conserved region, and linked to a non-viroid 5′ sequence, which acted as an internal control for Ribonuclease activity. Extracts from CCCVd-infected coconut (Cocos nucifera) and African oil (Elaeis guineensis) palms protected three major fragments of approximately 250, 125 and 50 nt and a variable number of minor fragments. Extracts of healthy coconut palms, Potato spindle tuber viroid-infected tomato and transfer RNA did not protect the probe. The approximately 250 nt fragment is predicted to indicate the presence of monomers and dimers of circular CCCVd246, linear CCCVd246 with the same termini as the probe and point mutants of these forms. The origin of smaller protected fragments is discussed. RPA-detected CCCVd sequences in 13 of 18 oil palms surveyed in a commercial plantation in Malaysia. Signal intensity varied between the positive oil palms and was generally lower than in coconut palms infected with CCCVd. An infection phenotype was implied but not confirmed by the observation that in a group of 10 oil palms with orange leaf spotting, 9 contained CCCVd, whereas in a group of 8 palms without orange spotting, the viroid was detected in 4. Of four coconut palms in Sri Lanka shown by dot-blot Assay to contain CCCVd-related RNA, one was shown by RPA to be positive for the CCCVd246 sequence. RPA is therefore a robust and sensitive test for CCCVd sequences, and our results show that sequences closely related to CCCVd246 are not confined to the Philippines.
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Detection of Coconut cadang‐cadang viroid sequences in oil and coconut palm by Ribonuclease Protection Assay
Annals of Applied Biology, 2008Co-Authors: Ganesan Vadamalai, A.a.f.l.k. Perera, D. Hanold, M. A. Rezaian, John W. RandlesAbstract:A Ribonuclease Protection Assay (RPA) has been developed for detecting Coconut cadang-cadang viroid (CCCVd) sequences. An RNA probe complementary to full-length CCCVd246 was used, terminating at nucleotide 65 in the upper conserved region, and linked to a non-viroid 5′ sequence, which acted as an internal control for Ribonuclease activity. Extracts from CCCVd-infected coconut (Cocos nucifera) and African oil (Elaeis guineensis) palms protected three major fragments of approximately 250, 125 and 50 nt and a variable number of minor fragments. Extracts of healthy coconut palms, Potato spindle tuber viroid-infected tomato and transfer RNA did not protect the probe. The approximately 250 nt fragment is predicted to indicate the presence of monomers and dimers of circular CCCVd246, linear CCCVd246 with the same termini as the probe and point mutants of these forms. The origin of smaller protected fragments is discussed. RPA-detected CCCVd sequences in 13 of 18 oil palms surveyed in a commercial plantation in Malaysia. Signal intensity varied between the positive oil palms and was generally lower than in coconut palms infected with CCCVd. An infection phenotype was implied but not confirmed by the observation that in a group of 10 oil palms with orange leaf spotting, 9 contained CCCVd, whereas in a group of 8 palms without orange spotting, the viroid was detected in 4. Of four coconut palms in Sri Lanka shown by dot-blot Assay to contain CCCVd-related RNA, one was shown by RPA to be positive for the CCCVd246 sequence. RPA is therefore a robust and sensitive test for CCCVd sequences, and our results show that sequences closely related to CCCVd246 are not confined to the Philippines.
Stephanie M Krebs - One of the best experts on this subject based on the ideXlab platform.
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Multiprobe Ribonuclease Protection Assay for simultaneous measurement of mRNA expression.
Current protocols in immunology, 2003Co-Authors: Howard A Young, Jeffrey J Subleski, Stephanie M KrebsAbstract:The multiprobe RNase Protection Assay enables investigators to monitor RNA expression of 8-12 genes with as little as 1 microg of total RNA. The commercial availability of numerous multi-gene template sets makes this Assay practical for all basic research programs.
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Current Protocols in Immunology - Multiprobe Ribonuclease Protection Assay for Simultaneous Measurement of mRNA Expression
Current Protocols in Immunology, 2003Co-Authors: Howard A Young, Jeffrey J Subleski, Stephanie M KrebsAbstract:The multiprobe RNase Protection Assay enables investigators to monitor RNA expression of 8-12 genes with as little as 1 microg of total RNA. The commercial availability of numerous multi-gene template sets makes this Assay practical for all basic research programs.
Takashi Muramatsu - One of the best experts on this subject based on the ideXlab platform.
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The ratio of splicing variants of MGC-24/CD164, a sialomucin, correlates with the metastatic potential of colorectal carcinomas.
Journal of biochemistry, 2000Co-Authors: Takanori Matsui, Nobuyuki Kurosawa, Kenji Hibi, Yasushi Kasai, Junichi Sakamoto, Eatsuki Ito, Akimasa Nakao, Takashi MuramatsuAbstract:MGC-24/CD164 is a sialomucin expressed in many normal and cancerous tissues. In humans, soluble and transmembrane forms of MGC-24 are produced by alternative splicing. The total MGC-24 RNA level was found to be lower in human colorectal carcinomas as compared with the adjacent normal mucosal tissues. Lower MGC-24 mRNA levels in colon carcinomas and in the adjacent normal mucosa epithelium correlate with lymphatic vessel invasion by the carcinoma. The ratio of the soluble form to the transmembrane form of the mRNA in colorectal carcinomas was determined by Ribonuclease Protection Assay. Higher ratios were correlated with less venous invasion and less remote metastasis, which became evident during postoperative observation.
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the ratio of splicing variants of mgc 24 cd164 a sialomucin correlates with the metastatic potential of colorectal carcinomas
Journal of Biochemistry, 2000Co-Authors: Takanori Matsui, Nobuyuki Kurosawa, Kenji Hibi, Yasushi Kasai, Junichi Sakamoto, Eatsuki Ito, Akimasa Nakao, Takashi MuramatsuAbstract:MGC-24/CD164 is a sialomucin expressed in many normal and cancerous tissues. In humans, soluble and transmembrane forms of MGC-24 are produced by alternative splicing. The total MGC-24 RNA level was found to be lower in human colorectal carcinomas as compared with the adjacent normal mucosal tissues. Lower MGC-24 mRNA levels in colon carcinomas and in the adjacent normal mucosa epithelium correlate with lymphatic vessel invasion by the carcinoma. The ratio of the soluble form to the transmembrane form of the mRNA in colorectal carcinomas was determined by Ribonuclease Protection Assay. Higher ratios were correlated with less venous invasion and less remote metastasis, which became evident during postoperative observation.
