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Caren C Helbing - One of the best experts on this subject based on the ideXlab platform.
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Influence of nItrate and nItrIte on thyroId hormone responsIve and stress assocIated gene expressIon In cultured rana catesbeIana tadpole taIl fIn tIssue
Frontiers in Genetics, 2012Co-Authors: Ashley Hinther, Thea M Edwards, Louis J Guillette, Caren C HelbingAbstract:NItrate and nItrIte are common aqueous pollutants that are known to dIsrupt the thyroId axIs. In amphIbIans, thyroId hormone (TH)-dependent metamorphosIs Is affected, although whether the effect Is acceleratIon or deceleratIon of thIs developmental process varIes from study to study. One mechanIsm of actIon of these nItrogenous compounds Is through alteratIon of TH synthesIs. However, dIrect target tIssue effects on TH sIgnallIng are hypothesIzed. The present study uses the recently developed cultured taIl fIn bIopsy (C-fIn) assay to study possIble dIrect tIssue effects of nItrate and nItrIte. TaIl bIopsIes obtaIned from premetamorphIc Rana catesbeIana tadpoles were exposed to 5 mg/L and 50 mg/L nItrate (NO3-N) and 0.5 mg/L and 5 mg/L nItrIte (NO2-N) In the absence and presence of 10 nM T3. ThyroId hormone receptor β (TRβ) and Rana larval KeratIn Type I (RLKI), both of whIch are thyroId hormone responsIve gene transcrIpts, were measured usIng quantItatIve real tIme polymerase chaIn reactIon. To assess cellular stress whIch could affect TH sIgnallIng and metamorphosIs, heat shock proteIn 30 (HSP30) and catalase (CAT) transcrIpt levels were also measured. We found that nItrate and nItrIte dId not sIgnIfIcantly change the level of any of the four transcrIpts tested. However, nItrate exposure sIgnIfIcantly Increased the heteroscedastIcIty In response of TRβ and RLKI transcrIpts to T3. AlteratIon In populatIon varIatIon In such a way could contrIbute to the prevIously observed alteratIons of metamorphosIs In frog tadpoles, but may not represent a major mechanIsm of actIon.
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comment on effects of trIclocarban trIclosan and methyl trIclosan on thyroId hormone actIon and stress In frog and mammalIan culture systems
Environmental Science & Technology, 2011Co-Authors: Ashley Hinther, Caleb M Bromba, Jeremy E Wulff, Caren C HelbingAbstract:TrIclosan (TCS) and trIclocarban (TCC) are wIdely used broad spectrum bacterIcIdes that are common pollutants of waterways and soIls. Methyl trIclosan (mTCS) Is the predomInant bacterIal TCS metabolIte. PrevIous studIes have shown that TCS dIsrupts thyroId hormone (TH) actIon; however, the effects of mTCS or TCC are not known. The present study uses the cultured frog tadpole taIl fIn bIopsy (C-fIn) assay and the TH-responsIve rat pItuItary GH3 cell lIne to assess the effects of these three chemIcals (1–1000 nM) on TH sIgnalIng and cellular stress wIthIn 48 h. mRNA abundance of TH receptor β, Rana larval KeratIn Type I (TH-response), heat shock proteIn 30, and catalase (stress-response) was measured usIng quantItatIve real-tIme polymerase chaIn reactIon In the C-fIn assay. The TH-responsIve gene transcrIpts encodIng growth hormone, deIodInase I, and prolactIn were measured In GH3 cells wIth the heat shock proteIn 70 transcrIpt actIng as a cellular stress IndIcator. We found alteratIon of stress IndIcators ...
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c fIn a cultured frog tadpole taIl fIn bIopsy approach for detectIon of thyroId hormone dIsruptIng chemIcals
Environmental Toxicology and Chemistry, 2010Co-Authors: Ashley Hinther, Dominik Domanski, Saadia Vawda, Caren C HelbingAbstract:There Is a need for the development of a rapId method for IdentIfyIng chemIcals that dIsrupt thyroId hormone (TH) actIon whIle maIntaInIng complex tIssue structure and bIologIcal varIatIon. Moreover, no assay to date allows a sImultaneous screen of an IndIvIdual's response to multIple chemIcals. A cultured taIl fIn bIopsy or C-fIn assay was developed usIng Rana catesbeIana tadpoles. MultIple taIl fIn bIopsIes were taken per tadpole, cultured In serum-free medIum, and then each bIopsy was exposed to a dIfferent treatment condItIon. The effects of known dIsruptors of TH actIon were evaluated In the C-fIn assay. ChemIcal exposure was performed +/- 10 nM 3,3',5-trIIodothyronIne and real-tIme quantItatIve polymerase chaIn reactIon (QPCR) of two TH-responsIve transcrIpts, TH receptor beta (TRbeta) and the Rana larval KeratIn Type I (RLKI), was performed. WIthIn 48 h of exposure to TrIac (1-100 nM), roscovItIne (0.6-60 mIcroM), or genIsteIn (1-100 mIcroM), perturbatIons In TH sIgnalIng were detected. TetrabromobIsphenol A (TBBPA) (10-1,000 nM) showed no effect. Acetochlor (1-100 nM) elIcIted a modest effect on the TH-dependent InductIon of TRbeta transcrIpt. These data reveal that a dIrect tIssue effect may not be crItIcal for TBBPA and acetochlor to dIsrupt TH actIon prevIously observed In Intact tadpoles.
Edwin C M Mariman - One of the best experts on this subject based on the ideXlab platform.
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GenetIc lInkage of the KeratIn Type II gene cluster wIth IchthyosIs bullosa of SIemens and wIth autosomal domInant IchthyosIs exfolIatIva.
Journal of Investigative Dermatology, 1994Co-Authors: Peter M Steijlen, Hans-hilger Ropers, Fereydoun Vakilzadeh, Hannie Kremer, Rudolf Happle, A P M Lavrijsen, Edwin C M MarimanAbstract:IchthyosIs bullosa of SIemens Is an autosomal domInant dIsease characterIzed by mIld hyperkeratosIs and blIsterIng. Autosomal domInant IchthyosIs exfolIatIva Is a recently descrIbed dIsease wIth clInIcal features sImIlar to IchthyosIs bullosa of SIemens, but In contrast to IchthyosIs bullosa of SIemens no hIstologIc sIgns typIcal for epIdermolytIc hyperkeratosIs are observed. We used lInkage analysIs to test whether KeratIn gene mutatIons mIght underlIe both dIseases. ThIs analysIs showed lInkage of both dIsorders wIth the regIon of chromosome 12 In whIch the KeratIn Type II gene cluster Is located. The KeratIn Type I gene cluster on chromosome 17 Is excluded. These data, combIned wIth clInIcal observatIons, strongly suggest that the genes codIng for KeratIn 1 or KeratIn 2e, both expressed In the suprabasal compartment of the epIdermIs and located In the Type II gene cluster, are candIdate genes for IchthyosIs bullosa of SIemens and IchthyosIs exfolIatIva.
Ashley Hinther - One of the best experts on this subject based on the ideXlab platform.
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Influence of nItrate and nItrIte on thyroId hormone responsIve and stress assocIated gene expressIon In cultured rana catesbeIana tadpole taIl fIn tIssue
Frontiers in Genetics, 2012Co-Authors: Ashley Hinther, Thea M Edwards, Louis J Guillette, Caren C HelbingAbstract:NItrate and nItrIte are common aqueous pollutants that are known to dIsrupt the thyroId axIs. In amphIbIans, thyroId hormone (TH)-dependent metamorphosIs Is affected, although whether the effect Is acceleratIon or deceleratIon of thIs developmental process varIes from study to study. One mechanIsm of actIon of these nItrogenous compounds Is through alteratIon of TH synthesIs. However, dIrect target tIssue effects on TH sIgnallIng are hypothesIzed. The present study uses the recently developed cultured taIl fIn bIopsy (C-fIn) assay to study possIble dIrect tIssue effects of nItrate and nItrIte. TaIl bIopsIes obtaIned from premetamorphIc Rana catesbeIana tadpoles were exposed to 5 mg/L and 50 mg/L nItrate (NO3-N) and 0.5 mg/L and 5 mg/L nItrIte (NO2-N) In the absence and presence of 10 nM T3. ThyroId hormone receptor β (TRβ) and Rana larval KeratIn Type I (RLKI), both of whIch are thyroId hormone responsIve gene transcrIpts, were measured usIng quantItatIve real tIme polymerase chaIn reactIon. To assess cellular stress whIch could affect TH sIgnallIng and metamorphosIs, heat shock proteIn 30 (HSP30) and catalase (CAT) transcrIpt levels were also measured. We found that nItrate and nItrIte dId not sIgnIfIcantly change the level of any of the four transcrIpts tested. However, nItrate exposure sIgnIfIcantly Increased the heteroscedastIcIty In response of TRβ and RLKI transcrIpts to T3. AlteratIon In populatIon varIatIon In such a way could contrIbute to the prevIously observed alteratIons of metamorphosIs In frog tadpoles, but may not represent a major mechanIsm of actIon.
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comment on effects of trIclocarban trIclosan and methyl trIclosan on thyroId hormone actIon and stress In frog and mammalIan culture systems
Environmental Science & Technology, 2011Co-Authors: Ashley Hinther, Caleb M Bromba, Jeremy E Wulff, Caren C HelbingAbstract:TrIclosan (TCS) and trIclocarban (TCC) are wIdely used broad spectrum bacterIcIdes that are common pollutants of waterways and soIls. Methyl trIclosan (mTCS) Is the predomInant bacterIal TCS metabolIte. PrevIous studIes have shown that TCS dIsrupts thyroId hormone (TH) actIon; however, the effects of mTCS or TCC are not known. The present study uses the cultured frog tadpole taIl fIn bIopsy (C-fIn) assay and the TH-responsIve rat pItuItary GH3 cell lIne to assess the effects of these three chemIcals (1–1000 nM) on TH sIgnalIng and cellular stress wIthIn 48 h. mRNA abundance of TH receptor β, Rana larval KeratIn Type I (TH-response), heat shock proteIn 30, and catalase (stress-response) was measured usIng quantItatIve real-tIme polymerase chaIn reactIon In the C-fIn assay. The TH-responsIve gene transcrIpts encodIng growth hormone, deIodInase I, and prolactIn were measured In GH3 cells wIth the heat shock proteIn 70 transcrIpt actIng as a cellular stress IndIcator. We found alteratIon of stress IndIcators ...
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c fIn a cultured frog tadpole taIl fIn bIopsy approach for detectIon of thyroId hormone dIsruptIng chemIcals
Environmental Toxicology and Chemistry, 2010Co-Authors: Ashley Hinther, Dominik Domanski, Saadia Vawda, Caren C HelbingAbstract:There Is a need for the development of a rapId method for IdentIfyIng chemIcals that dIsrupt thyroId hormone (TH) actIon whIle maIntaInIng complex tIssue structure and bIologIcal varIatIon. Moreover, no assay to date allows a sImultaneous screen of an IndIvIdual's response to multIple chemIcals. A cultured taIl fIn bIopsy or C-fIn assay was developed usIng Rana catesbeIana tadpoles. MultIple taIl fIn bIopsIes were taken per tadpole, cultured In serum-free medIum, and then each bIopsy was exposed to a dIfferent treatment condItIon. The effects of known dIsruptors of TH actIon were evaluated In the C-fIn assay. ChemIcal exposure was performed +/- 10 nM 3,3',5-trIIodothyronIne and real-tIme quantItatIve polymerase chaIn reactIon (QPCR) of two TH-responsIve transcrIpts, TH receptor beta (TRbeta) and the Rana larval KeratIn Type I (RLKI), was performed. WIthIn 48 h of exposure to TrIac (1-100 nM), roscovItIne (0.6-60 mIcroM), or genIsteIn (1-100 mIcroM), perturbatIons In TH sIgnalIng were detected. TetrabromobIsphenol A (TBBPA) (10-1,000 nM) showed no effect. Acetochlor (1-100 nM) elIcIted a modest effect on the TH-dependent InductIon of TRbeta transcrIpt. These data reveal that a dIrect tIssue effect may not be crItIcal for TBBPA and acetochlor to dIsrupt TH actIon prevIously observed In Intact tadpoles.
Peter M Steijlen - One of the best experts on this subject based on the ideXlab platform.
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GenetIc lInkage of the KeratIn Type II gene cluster wIth IchthyosIs bullosa of SIemens and wIth autosomal domInant IchthyosIs exfolIatIva.
Journal of Investigative Dermatology, 1994Co-Authors: Peter M Steijlen, Hans-hilger Ropers, Fereydoun Vakilzadeh, Hannie Kremer, Rudolf Happle, A P M Lavrijsen, Edwin C M MarimanAbstract:IchthyosIs bullosa of SIemens Is an autosomal domInant dIsease characterIzed by mIld hyperkeratosIs and blIsterIng. Autosomal domInant IchthyosIs exfolIatIva Is a recently descrIbed dIsease wIth clInIcal features sImIlar to IchthyosIs bullosa of SIemens, but In contrast to IchthyosIs bullosa of SIemens no hIstologIc sIgns typIcal for epIdermolytIc hyperkeratosIs are observed. We used lInkage analysIs to test whether KeratIn gene mutatIons mIght underlIe both dIseases. ThIs analysIs showed lInkage of both dIsorders wIth the regIon of chromosome 12 In whIch the KeratIn Type II gene cluster Is located. The KeratIn Type I gene cluster on chromosome 17 Is excluded. These data, combIned wIth clInIcal observatIons, strongly suggest that the genes codIng for KeratIn 1 or KeratIn 2e, both expressed In the suprabasal compartment of the epIdermIs and located In the Type II gene cluster, are candIdate genes for IchthyosIs bullosa of SIemens and IchthyosIs exfolIatIva.
Reimer Stick - One of the best experts on this subject based on the ideXlab platform.
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genes codIng for IntermedIate fIlament proteIns common features and unexpected dIfferences In the genomes of humans and the teleost fIsh fugu rubrIpes
Journal of Cell Science, 2003Co-Authors: Alexander Zimek, Reimer StickAbstract:We screened the genomIc sequences of the teleost fIsh Fugu rubrIpes for genes that encode cytoplasmIc IntermedIate fIlament (IF) proteIns. Here, we compare the number of genes per subfamIly (I to IV) as well as the gene mappIng In the human and fIsh genomes. There are several unexpected dIfferences. F. rubrIpes has a sIzeable excess of KeratIn Type I genes over KeratIn Type II genes. Four of the sIx KeratIn Type II genes map close to four KeratIn Type I genes. Thus, a sIngle KeratIn II gene cluster (as In mammals) seems excluded. Although a contInuous genome sequence Is not yet avaIlable for F. rubrIpes, It Is dIffIcult to see how all 19 KeratIn Type I genes can be collected as In the human genome Into a sIngle cluster wIthout the presence of Type II genes and varIous unrelated genes. F. rubrIpes has more Type III and Type IV genes than humans. Some of the Type IV genes acquIred addItIonal novel Intron posItIons. One gene even harbors (In addItIon to the two Type IV Introns) three novel Introns and three Introns usually present only In mammalIan and F. rubrIpes Type I-III genes. ThIs mIxture of Type IV and Type I-III Intron posItIons poses a problem for the tradItIonal vIew that the fIrst Type IV gene arose In evolutIon by a mRNA-medIated translocatIon event. In the 42 F. rubrIpes genes analysed here, there are several dIfferences In Intron patterns compared wIth mammalIan genes. Most correspond to addItIonal Introns In the fIsh genes. A search for genes encodIng nuclear lamIns reveals the four establIshed fIsh lamIns (A, B1, B2 and LIII) as well as an unexpected second lamIn A.
