The Experts below are selected from a list of 90 Experts worldwide ranked by ideXlab platform
Werner Hoffmann - One of the best experts on this subject based on the ideXlab platform.
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molecular anatomy of a Skin Gland histochemical and biochemical investigations on the mucous Glands of xenopus laevis
Journal of Histochemistry and Cytochemistry, 1994Co-Authors: Udo Schumacher, E Adam, F Hauser, J C Probst, Werner HoffmannAbstract:: The purpose of this study was to investigate the structure and chemical composition of the mucous Skin Gland of Xenopus laevis by combined morphological and biochemical techniques. Protein backbones of mucins were localized immunohistochemically in the Gland with anti-peptide antibodies. Acid mucins were demonstrated by conventional histochemical techniques and their terminal carbohydrate residues were localized by lectin histochemistry. A close correlation between antibody and lectin binding of the same glycoproteins was achieved on Western blots from isolated Skin Gland mucins, indicating that the lectin-binding sites were due to defined mucin molecules. The cone cell, thought to be a degenerative cell in the past, contained mucin granules with an electron-dense core, strong PAS reactivity, a special lectin-binding pattern, and localization of integumentary mucins FIM-B.1 and FIM-C.1. These results indicate that cone cells are a distinct cell type, elaborating and releasing particular mucins, and that functional heterogeneity of mucus-producing cells exists in the mucous Skin Glands of X. laevis.
Michael J. Tyler - One of the best experts on this subject based on the ideXlab platform.
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an unusual kynurenine containing opioid tetrapeptide from the Skin Gland secretion of the australian red tree frog litoria rubella sequence determination by electrospray mass spectrometry
Rapid Communications in Mass Spectrometry, 2011Co-Authors: Simon T Ellissteinborner, Michael J. Tyler, Denis B Scanlon, Ian F Musgrave, T Nha T Tran, Sandra Hack, Tianfang Wang, Andrew D Abell, John H BowieAbstract:The Kyn-containing peptide FP-Kyn-L(NH2) is an unusual minor component of the Skin peptide profile of the Australian red tree frog Litoria rubella collected from an area within a 20 kilometre radius of Alice Springs in central Australia. The structure was determined by electrospray mass spectrometry and synthesis. The major component of the Skin secretion is the analogous tryptophyllin peptide FPWL(NH2). Both peptides show opioid activity at 10–7 M, and are likely to act via the μ opioid receptor. Copyright © 2011 John Wiley & Sons, Ltd.
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Do Skin peptide profiles reflect speciation in the Australian treefrog Litoria caerulea (Anura : Hylidae)?
Australian Journal of Zoology, 2000Co-Authors: Stephen C. Donnellan, Michael J. Tyler, Paul Monis, Adam Barclay, Anna MedlinAbstract:Profiles of Skin Gland peptides of the tree frog Litoria caerulea from Australia show substantial divergence among geographic locations. Indeed, two divergent groups of populations, ‘eastern’ and ‘northern’, are apparent from a phenetic analysis of similarities of Skin Gland peptide profiles among populations of L. caerulea. We analyse variation in nuclear genes (allozyme frequencies) and the mitochondrial genome (haplotype relationships and frequencies) to test the taxonomic significance of differences apparent among profiles of Skin Gland peptides. Both molecular genetic data sets identified the same two groups apparent in the profiles of Skin Gland peptides. However, neither molecular data set, under an evolutionary species concept, provides strong enough evidence to support recognition of these groups as separate species. These data imply that the genetic basis of the inheritance and expression of Skin Gland peptides requires further characterisation.
Tanya N Gill - One of the best experts on this subject based on the ideXlab platform.
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hormonal regulation of Skin Gland development in the toad bufo boreas the role of the thyroid hormones and corticosterone
General and Comparative Endocrinology, 1995Co-Authors: Tyrone B Hayes, Tanya N GillAbstract:At metamorphic climax, anurans develop Skin Glands that migrate from the epidermis into the dermis. Thyroxine (T4) stimulates Skin Gland differentiation and migration, and a previous study showed that corticosterone (Cort) treatment of larvae is inhibitory. The current study used histological analyses to address the mechanism of CoWs prevention of Skin Gland development. Two types of Glands were observed in controls at metamorphic climax: The first type resembled granular Glands found in adults and the second resembled mucous Glands. Differential staining revealed that the two Gland morphologies represented functionally distinct granular and mucous Glands. Treatment of larvae from Gosner Stages 35-42 with Cort or the goitrogen, thiourea (Thio), caused a reduction in the number of mucous (P < 0.05) but not granular Glands. The similarity in the effects of Cort and Thio suggested that Cort inhibited Skin Gland development indirectly by down-regulating the hypothalamo-pituitary-thyroid axis. T4 treatment of larvae reversed the effects of Thio (T4 + Thio-treated animals); however, animals treated with T4 + Cort had no Skin Glands of either type. Triiodothyronine (T3) treatment of larvae resulted in the complete absence of Skin Glands with a limited number of Gland nests (epidermal precursors of dermal Skin Glands), but stimulated epidermal growth. T3 + Thio- or T3 + Cort-treated animals also completely lacked Skin Glands. These data suggest that T3 favors epidermal growth at the cost of Skin Gland differentiation. Furthermore, we suggest that Cort inhibits Skin Gland development indirectly through its enhancement of T4 to T3 conversions, and that inhibition of Skin Glands is caused by an increase in T3 resulting from Cort treatment.
John H Bowie - One of the best experts on this subject based on the ideXlab platform.
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an unusual kynurenine containing opioid tetrapeptide from the Skin Gland secretion of the australian red tree frog litoria rubella sequence determination by electrospray mass spectrometry
Rapid Communications in Mass Spectrometry, 2011Co-Authors: Simon T Ellissteinborner, Michael J. Tyler, Denis B Scanlon, Ian F Musgrave, T Nha T Tran, Sandra Hack, Tianfang Wang, Andrew D Abell, John H BowieAbstract:The Kyn-containing peptide FP-Kyn-L(NH2) is an unusual minor component of the Skin peptide profile of the Australian red tree frog Litoria rubella collected from an area within a 20 kilometre radius of Alice Springs in central Australia. The structure was determined by electrospray mass spectrometry and synthesis. The major component of the Skin secretion is the analogous tryptophyllin peptide FPWL(NH2). Both peptides show opioid activity at 10–7 M, and are likely to act via the μ opioid receptor. Copyright © 2011 John Wiley & Sons, Ltd.
Udo Schumacher - One of the best experts on this subject based on the ideXlab platform.
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molecular anatomy of a Skin Gland histochemical and biochemical investigations on the mucous Glands of xenopus laevis
Journal of Histochemistry and Cytochemistry, 1994Co-Authors: Udo Schumacher, E Adam, F Hauser, J C Probst, Werner HoffmannAbstract:: The purpose of this study was to investigate the structure and chemical composition of the mucous Skin Gland of Xenopus laevis by combined morphological and biochemical techniques. Protein backbones of mucins were localized immunohistochemically in the Gland with anti-peptide antibodies. Acid mucins were demonstrated by conventional histochemical techniques and their terminal carbohydrate residues were localized by lectin histochemistry. A close correlation between antibody and lectin binding of the same glycoproteins was achieved on Western blots from isolated Skin Gland mucins, indicating that the lectin-binding sites were due to defined mucin molecules. The cone cell, thought to be a degenerative cell in the past, contained mucin granules with an electron-dense core, strong PAS reactivity, a special lectin-binding pattern, and localization of integumentary mucins FIM-B.1 and FIM-C.1. These results indicate that cone cells are a distinct cell type, elaborating and releasing particular mucins, and that functional heterogeneity of mucus-producing cells exists in the mucous Skin Glands of X. laevis.