151
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Li CH, Izdebski J, Chung D. Primary structure of fox pituitary growth hormone. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1989; 33:70-2. [PMID: 2722401 DOI: 10.1111/j.1399-3011.1989.tb00685.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Tryptic digests of fox growth hormone (fGH) were separated by reverse phase high performance liquid chromatography (HPLC) and by paper electrophoresis. From the amino acid composition of these tryptic peptides and from their alignment with the expected tryptic peptides from bovine growth hormone (bGH), the primary structure of fGH is proposed. There are only 17 amino acid residues which are different in these two growth hormone molecules.
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152
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Li CH, Oosthuizen MM, Chung D. Primary structure of elephant pituitary prolactin. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1989; 33:67-9. [PMID: 2722400 DOI: 10.1111/j.1399-3011.1989.tb00684.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Tryptic digests of elephant pituitary prolactin (elePRL) were separated by reverse phase high performance liquid chromatography (HPLC) and paper electrophoresis. From the amino acid composition, the amino acid sequencing of selected peptides, and from their alignment with expected tryptic peptides from ovine prolactin (oPRL), the primary sequence of elePRL is proposed.
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153
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Li CH, Oosthuizen MM, Chung D. Isolation and primary structures of elephant adrenocorticotropin and beta-lipotropin. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1988; 32:573-8. [PMID: 2854538 DOI: 10.1111/j.1399-3011.1988.tb01389.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Adrenocorticotropin and beta-lipotropin have been isolated and purified from elephant pituitary glands. The primary structures of these two hormones were determined by amino acid and sequence analyses of enzymatically cleaved peptides from the hormones. Peptide purification involved the use of gel filtration, reverse phase high performance liquid chromatography, and paper electrophoresis.
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154
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Li CH, Chung D, Izdebski J, Majewski T, Mowles TF. Isolation and characterization of growth hormone from blue fox pituitary glands. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1988; 31:201-4. [PMID: 3366551 DOI: 10.1111/j.1399-3011.1988.tb00023.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Growth hormone has been purified to homogeneity from blue fox pituitary glands. It has 191 amino acids with two disulfide bridges and a single tryptophan residue. The somatotropin activity is only 8% when compared with the bovine hormone in the receptor-binding assay. From radioimmunoassay data using baboon antisera to porcine or bovine growth hormone, the fox hormone has 14-17% immunoreactivity of bovine or porcine hormone.
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155
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Li CH, Chung D, Bewley TA, Cabrera CM. Elephant prolactin: isolation and characterization. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1987; 29:472-7. [PMID: 3596899 DOI: 10.1111/j.1399-3011.1987.tb02273.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Prolactin was isolated from anterior lobes of elephant pituitary glands. It consisted of 199 amino acids with three disulfide bridges and two tryptophan residues as found in prolactin from other species. The sequence of the NH2-terminal 28 amino acids was determined and shown homologous with the ovine hormone. In comparison with ovine prolactin, a marked difference was seen in the methionine content; the elephant hormone possessed only 18-34% lactogenic potency. The conformation of elephant prolactin was examined by zero order, second order and circular dichroism spectroscopy. The alpha helical content was estimated to be about 60%. In comparison with prolactins from other species, the second order spectra of elephant prolactin suggest that the local microenvironment for one or both tryptophan residues is somewhat different.
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156
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Li CH, Ramasharma K, Yamashiro D, Chung D. Gonadotropin-releasing peptide from human follicular fluid: isolation, characterization, and chemical synthesis. Proc Natl Acad Sci U S A 1987; 84:959-62. [PMID: 3547404 PMCID: PMC304339 DOI: 10.1073/pnas.84.4.959] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
A gonadotropin-releasing peptide has been isolated from human follicular fluid. Its amino acid composition and sequence are completely different from the hypothalamic lutropin-releasing hormone. It is designated human follicular gonadotropin-releasing peptide and abbreviated as hF-GRP. The primary structure of this peptide (H-Thr-Asp-Thr-Ser-His-His-Asp-Gln-Asp-His-Pro-Thr-Phe-Asn-OH) has been confirmed by chemical synthesis. In the mouse pituitary incubation assay, the ED50 value for follitropin or lutropin release is estimated to be 1.2-1.6 nM.
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157
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Li CH, Bewley TA, Chung D, Oosthuizen MM. Elephant growth hormone. Isolation and characterization. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1987; 29:62-7. [PMID: 3570656 DOI: 10.1111/j.1399-3011.1987.tb02230.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Growth hormone has been purified to homogeneity from elephant pituitary glands. It has 191 amino acids with two disulfide bridges and a single tryptophan residue. The somatotropin activity is only 15% when compared with the bovine hormone in the radioreceptor binding assay. From circular dichroism spectra alpha-helical content of elephant growth hormone is estimated to be 50%. Difference absorption spectra of the hormone suggest the presence of a hydrogen bond between the single Trp and a carboxylate ion.
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158
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Teo P, Chung D. An accurate method of 192Ir wire implantation for locally advanced carcinoma of breast. Acta Oncol 1987; 26:273-6. [PMID: 3120759 DOI: 10.3109/02841868709089974] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
An accurate and reproducible method of 192Ir wire implantation of locally advanced breast tumour after locoregional megavoltage external radiotherapy has been described. The method includes the use of cobex cast for breast and tumour immobilization, of computed tomography for tumour localization, of computer for planning and isodose display and of specially made template to guide insertion of trocars and 192Ir wires.
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159
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Abstract
Monkey growth hormone (MGH) has been purified by reverse-phase high-performance liquid chromatography (HPLC). Tryptic digests of MGH were separated by HPLC and paper electrophoresis. From amino acid composition, from NH2-terminal residue and sequence analyses of these tryptic peptides, and from their alignment with those of human growth hormone, the primary structure of MGH was proposed. There are only four residues which are different in these two growth hormone molecules.
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160
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Li CH, Chung D. Distinct behavior of beta-endorphin and corticotropin toward leucine aminopeptidase action. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1985; 26:113-7. [PMID: 2999016 DOI: 10.1111/j.1399-3011.1985.tb03187.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Reactions of human beta-endorphin, corticotropin and their synthetic analogs with leucine aminopeptidase have been investigated. The results confirmed previous findings that beta-endorphin is resistant to the aminopeptidase action whereas corticotropin is not. Beta-endorphin-(1-5) is completely digested by the enzyme while beta-endorphin-(1-17) is resistant. In contrast, the NH2-terminal 7 residues in corticotropin are removed readily by leucine aminopeptidase. This is confirmed by the observation that human corticotropin-(7-38) is not hydrolyzed by the enzyme. This contrasting behavior of the two hormones toward leucine aminopeptidase may be related to differences in their conformational structures.
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161
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Li CH, Hammonds RG, Ramasharma K, Chung D. Human seminal alpha inhibins: isolation, characterization, and structure. Proc Natl Acad Sci U S A 1985; 82:4041-4. [PMID: 3889920 PMCID: PMC397930 DOI: 10.1073/pnas.82.12.4041] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Two additional peptides with inhibin-like activity have been isolated from human seminal plasma. One consists of 52 amino acids and the other, 92 amino acids. They are designated alpha-inhibin-52 and alpha-inhibin-92. Sequence analyses show that the NH2-terminal 31 amino acids of alpha-inhibin-52 are identical to the structure of the inhibin-like peptide previously reported [ILP-(1-31), now designated alpha-inhibin-31], and the COOH-terminal 52 amino acids of alpha-inhibin-92 are identical to the structure of alpha-inhibin-52. The amino acid sequence of alpha-inhibin-92 is: (sequence in text) Bioassay data in mouse pituitaries in vitro show that alpha-inhibin-52 is 3.4 times more active and alpha-inhibin-92 is greater than 40 times more active than alpha-inhibin-31 in suppressing follitropin-release. Radioimmunoassay data indicate that alpha-inhibin-52 and alpha-inhibin-92 have only 60% immunoreactivity.
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162
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Chung D, Li CH. Evidence for the existence of [Gln9]-beta-lipotropin in human pituitary glands. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1985; 25:9-14. [PMID: 3980150 DOI: 10.1111/j.1399-3011.1985.tb02141.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The isolation of two peptides similar in amino acid composition to that of human beta-lipotropin is presented. Peptide patterns after enzymatic digestions of these two peptides by Staphylococcus aureus protease and by trypsin were nearly identical. Paper electrophoresis and amino acid analyses of acidic peptides generated from the enzymatic digestions of these two peptides indicate that there is an amide difference between the two peptides. It is proposed that this amide difference is in amino acid residue number nine, and that one is the human beta-lipotropin and the other its [Gln9] analog.
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163
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Hammond GL, Chung D, Li CH. Isolation of melanotropins and vasopressin from neuro-intermediate lobes of bovine pituitary glands. A simplified procedure. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1983; 22:161-3. [PMID: 6618760 DOI: 10.1111/j.1399-3011.1983.tb02081.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A simplified procedure for the isolation of alpha-melanotropin, beta-melanotropin and arginine vasopressin from the acid acetone extract of posterior-intermediate lobes of bovine pituitaries has been described. It involves essentially two steps: gel filtration on Sephadex G-10 and high performance liquid chromatography.
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164
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Li CH, Chung D. Isolation of pancreatic trypsin inhibitor from bovine pituitary glands. Proc Natl Acad Sci U S A 1983; 80:1204-6. [PMID: 6187006 PMCID: PMC393562 DOI: 10.1073/pnas.80.5.1204] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
A trypsin inhibitor has been isolated from bovine pituitary extracts. From its amino acid composition, NH2-terminal residue, mobility in paper electrophoresis, and behavior in high-performance liquid chromatography and from the tryptic pattern of the performic acid-oxidized material, it appears that the inhibitor is identical to the Kunitz and Northrop pancreatic trypsin inhibitor.
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165
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Li CH, Chung D. Studies on prolactin 48: isolation and properties of the hormone from horse pituitary glands. Arch Biochem Biophys 1983; 220:208-13. [PMID: 6830233 DOI: 10.1016/0003-9861(83)90402-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Isolation of prolactin from equine pituitary glands has been described. It has a potency of 42 IU/mg in the pigeon crop-sac test and consists of 199 amino acids. The hormone has only four half-cystine residues in contrast to other mammalian prolactins which have six residues. From NH2-terminal sequence analysis and amino acid composition of cyanogen bromide fragments, the NH2-terminal disulfide loop is missing in the equine prolactin molecule. Circular dichroism spectra indicate that the alpha-helical content of equine prolactin appears to be lower (50%) than that found in the ovine hormone (65%).
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166
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Hammond GL, Chung D, Li CH. Isolation and characterization of delta-melanotropin, a new peptide from bovine pituitary glands. Biochem Biophys Res Commun 1982; 108:118-23. [PMID: 7150276 DOI: 10.1016/0006-291x(82)91839-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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167
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Ng TB, Chung D, Li CH. Isolation and properties of beta-endorphin-(1-27)-like peptide from bovine brains. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1982; 19:343-7. [PMID: 6288592 DOI: 10.1111/j.1399-3011.1982.tb02613.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A beta-endorphin-(1-27)-like peptide was isolated from bovine cerebral hemisphere extracts by gel filtration, ion-exchange chromatography, high performance liquid chromatography and paper electrophoresis. The peptide had tyrosine as the amino-terminal residue and its amino acid composition was nearly identical to that of equine pituitary beta-EP-(1-27). It had also the same mobility as equine pituitary beta-EP-(1-27) in paper electrophoresis. In radioimmunoassay and opiate receptor-binding assay, the brain peptide had 50% activity when compared with human beta-endorphin-(1-27). Evidence for the occurrence of NH2-acetylated form of beta-endorphin-(1-27) is also presented.
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168
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Ng TB, Chung D, Li CH. Isolation and properties of beta-endorphin-(1-27), N alpha-acetyl-beta-endorphin, corticotropin, gamma-lipotropin and neurophysin from equine pituitary glands. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1981; 18:443-50. [PMID: 6281206 DOI: 10.1111/j.1399-3011.1981.tb03005.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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169
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Li CH, Ng TB, Yamashiro D, Chung D, Hammonds RG, Tseng LF. beta-Endorphin: isolation, amino acid sequence and synthesis of the hormone from horse pituitary glands. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1981; 18:242-8. [PMID: 6281204 DOI: 10.1111/j.1399-3011.1981.tb02978.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Beta-endorphin has been isolated from equine pituitaries. Its amino acid sequence is identical to that of ovine, bovine and camel beta-endorphins except for substitution of the threonine residue at position 6 by serine. The equine beta-endorphin has also been synthesized by the solid-phase method. In comparison with the human hormone, equine beta-endorphin was shown to possess 3 times the receptor-binding activity in rat membrane preparations and 1.6 times the analgesic potency in the mouse tail-flick assay.
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170
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Naudé RJ, Chung D, Li CH, Oelofsen W. beta-Lipotropin: primary structure of the hormone from the ostrich pituitary gland. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1981; 18:138-47. [PMID: 7309375 DOI: 10.1111/j.1399-3011.1981.tb02051.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The amino acid sequence of beta-lipotropin from the ostrich pituitary has been determined. It consists of 79 amino acids. The amino acid sequence has been determined as follows: H-(1)AlA-Leu-Pro-Pro-Ala-Ala-Met-Leu-Pro-(10)Ala-Ala-Ala-Glu-Glu-Glu-Glu-Gly-Gl u-Glu-(20)Glu-Glu-Glu-Gly-Glu-Ala-Glu-Lys-Glu-Asp-(30)Gly-Gly-Ser-Tyr-Arg-Met-A rg-His-Phe-Arg-(40)Trp-Gln-Ala-Pro-Leu-Lys-Asp-Lys-Arg-Tyr-(50)Gly-Gly-Phe-Met- Ser-Ser-Glu-Arg-Gly-Arg-(60)Ala-Pro-Leu-Val-Thr-Leu-Phe-Lys-Asn-Ala-(70)Ile-Val -Lys-Ser-Ala-Tyr-Lys-Lys-Gly-(79)Gln-OH. When compared with the primary structures of other known beta-lipotropins, the sequence at the NH2-terminal, beta-melanotropin and beta-endorphin portions of the molecule exhibit considerable variability.
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171
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Ng TB, Oosthuizen MM, Chung D, Li CH. Isolation and characterization of a new beta-melanotropin from horse pituitary glands. Biochem Biophys Res Commun 1981; 98:621-7. [PMID: 7225116 DOI: 10.1016/0006-291x(81)91159-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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172
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Chung D. The gentle touch... could we... should we? NURSING TIMES 1981; 77:287-90. [PMID: 6906746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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173
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Li CH, Chung D. Isolation, characterization and amino acid sequence of beta-lipotropin from human pituitary glands. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1981; 17:131-42. [PMID: 7228494 DOI: 10.1111/j.1399-3011.1981.tb01976.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Beta-Lipotropin has been purified to homogeneity from human pituitary glands. It consists of 89 amino acids with a molecular weight of 11 700. The lipolytic potency of the human hormone is identical to that of ovine beta-LPH. The amino acid sequence has been determined as follows: (see formula in text). When compared with the structure of the ovine hormone, the sequence at the NH2-terminal 33 residues exhibits considerable variability.
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174
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Naudé RJ, Chung D, Li CH, Oelofsen W. beta-Endorphin: primary structure of the hormone from the ostrich pituitary gland. Biochem Biophys Res Commun 1981; 98:108-14. [PMID: 7213380 DOI: 10.1016/0006-291x(81)91876-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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175
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Novak M, Monkus EF, Chung D, Buch M. Carnitine in the perinatal metabolism of lipids. I. Relationship between maternal and fetal plasma levels of carnitine and acylcarnitines. Pediatrics 1981; 67:95-100. [PMID: 7243438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Since premature infants have a limited capacity for fatty acid oxidation, supplementation with carnitine may improve their utilization of fat. Documentation of the source and extent of fetal carnitine reserves should explain the possible need for exogenous carnitine in the neonate. Correlation between free carnitine concentration in maternal and umbilical arterial plasma at birth (r = .45, P less than .01) indicates that the initial concentration of free carnitine in the newborn depends on the maternal level. Thin-layer chromatography shows more gamma-butyrobetaine in maternal than umbilical arterial plasma indicating higher availability of the precursor of carnitine biosynthesis. Elevated fatty acid oxidation in maternal tissues seems to be reflected by larger amounts of long-chain acylcarnitines in maternal plasma. Short-chain acylcarnitines, mainly acetylcarnitine, are higher in the umbilical vein than in maternal plasma (P less than .01) indicating that the conceptus (the placenta or fetus) is either producing more or utilizing less acetylcarnitine. Plasma levels of carnitine rapidly decrease in premature newborns during the first three days after birth if no exogenous carnitine is given (P less than .001), while no significant changes of total carnitine were detected in adult patients on total parenteral alimentation for one week. This difference indicates lower carnitine depots or limited capacity for carnitine biosynthesis in neonates. The possibility still requires further investigation that the development of the optimal rate of fatty acid oxidation in human newborns, as well as in other newborn mammals, may depend on the supply of exogenous carnitine.
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