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Steegmüller KW, Schäfer W, Lang E, von Flotow P, Junginger T. [Perioperative risk of surgical therapy of Crohn disease]. Chirurg 1992; 63:39-43. [PMID: 1547644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
301 patients, operated for Crohn's disease in a ten-year period (1980-1989) were analyzed retrospectively, regarding perioperative risk of bowel resection (n = 336). The overall mortality rate was 0.6% (elective 0, emergency 6%). The reasons of this low mortality rate are of different nature. Very important is a meticulous perioperative treatment and a standardized operative approach.
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227
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Rappen T, Schröder J, Leisse A, Wegener M, Schäfer W, Sauer NJ, Chang TY. Nonlinear absorption of two-dimensional magnetoexcitons in InxGa1-xAs/InyAl1-yAs quantum wells. PHYSICAL REVIEW. B, CONDENSED MATTER 1991; 44:13093-13096. [PMID: 9999498 DOI: 10.1103/physrevb.44.13093] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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228
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Barlos K, Gatos D, Kapolos S, Poulos C, Schäfer W, Yao WQ. Application of 2-chlorotrityl resin in solid phase synthesis of (Leu15)-gastrin I and unsulfated cholecystokinin octapeptide. Selective O-deprotection of tyrosine. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1991; 38:555-61. [PMID: 1819590 DOI: 10.1111/j.1399-3011.1991.tb01539.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The carboxyl terminal dipeptide amide, Fmoc-Asp-Phe-NH2, of gastrin and cholecystokinin (CCK) has been attached in high yield through its free side chain carboxyl group to the acid labile 2-chlorotrityl resin. The obtained peptide resin ester has been applied in the solid phase synthesis of partially protected (Leu15)-gastrin I utilising Fmoc-amino acids. Quantitative cleavage of this peptide from resin, with the t-butyl type side chain protection intact is achieved using mixtures of acetic acid/trifluoroethanol/dichloromethane. Under the same conditions complete detritylation of the tyrosine phenoxy function occurs simultaneously. Thus, the solid-phase synthesis of peptides selectively deprotected at the side chain of tyrosine is rendered possible by the use of 2-chlorotrityl resin and Fmoc-Tyr(Trt)-OH. The efficiency of this approach has been proved by the subsequent high-yield synthesis of three model peptides and the CCK-octapeptide.
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229
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Junginger T, Schäfer W, Böttger T. [Esophageal perforation--indications for surgical therapy]. Chirurg 1991; 62:800-4. [PMID: 1769260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
From January 1, 1970 to April 1, 1990, we treated 32 patients with esophageal perforations. 19 patients underwent surgical repair by bilateral closing suture (n = 10), mucosal suture, extramyotomy and semifundoplication in the presence of achalasia (n = 6). Three patients had subtotal esophagus resection with esophageal graft. Four of these patients died postoperatively, the site of intervention being unremarkable. We lost 7 out of 13 patients from the group subjected to conservative therapy. These results suggest a low risk in the surgical treatment of esophageal perforations when carried out at early stage. The conservative approach on the other hand constitutes an uncalculable risk factor. It should be thus be employed with utmost precaution, e.g. in case of minor perforation only, or in patients with incurable carcinoma.
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230
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Sanz L, Calvete JJ, Mann K, Schäfer W, Schmid ER, Töpfer-Petersen E. The amino acid sequence of AQN-3, a carbohydrate-binding protein isolated from boar sperm. Location of disulphide bridges. FEBS Lett 1991; 291:33-6. [PMID: 1936247 DOI: 10.1016/0014-5793(91)81097-r] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Gamete recognition and adhesion are essential steps in fertilization. Among others, carbohydrate-binding proteins on the sperm surface have been recognized to play a central role in the initial interaction of the male gamete with components of the zona pellucida of the homologous investing oocyte. We have isolated several members of a carbohydrate- and zona pellucida-binding protein family from ejaculated sperm. Here we report the biological origin and structural characterization of AQN-3, a component of this carbohydrate-binding family. The molecular weight of purified AQN-3 was determined by plasma desorption mass spectrometry. The protein was chemically and enzymatically degraded, the proteolytic fragments isolated and characterized by N-terminal sequencing and fast atom bombardment mass spectrometry. In this manner we established the complete amino acid sequence of AQN-3 and the location of its two disulphide bonds. No analogous protein sequence could be found in the MIPS protein sequence data bank, indicating that AQN-3 may belong to a novel mammalian carbohydrate-binding protein family.
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231
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Schäfer W. Chromatographische Methoden in der Biochemie. VonH. Sternbach. Thieme, Stuttgart 1991. XII, 194 S., Broschur DM 40.00. - ISBN 3-13-752601-9. Angew Chem Int Ed Engl 1991. [DOI: 10.1002/ange.19911031056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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232
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Torres T, Schäfer W. A facile synthesis of alkylidenebutenolides via thermal rearrangement of benzisoxazolequinones. Tetrahedron Lett 1991. [DOI: 10.1016/s0040-4039(00)93566-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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233
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Leo K, Göbel EO, Damen TC, Shah J, Schmitt-Rink S, Schäfer W, Müller JF, Köhler K, Ganser P. Subpicosecond four-wave mixing in GaAs/AlxGa1-xAs quantum wells. PHYSICAL REVIEW. B, CONDENSED MATTER 1991; 44:5726-5737. [PMID: 9998416 DOI: 10.1103/physrevb.44.5726] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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234
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Calvete JJ, Schäfer W, Soszka T, Lu WQ, Cook JJ, Jameson BA, Niewiarowski S. Identification of the disulfide bond pattern in albolabrin, an RGD-containing peptide from the venom of Trimeresurus albolabris: significance for the expression of platelet aggregation inhibitory activity. Biochemistry 1991; 30:5225-9. [PMID: 2036389 DOI: 10.1021/bi00235a016] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Albolabrin is a 73 amino acid peptide isolated from the venom of Trimeresurus albolabris. It contains an RGD sequence and 12 cysteines and is a potent inhibitor of both platelet aggregation and fibrinogen binding to the GPIIb/IIIa complex. This protein shows a high degree of analogy (primarily due to the alignment of all cysteines and the RGD) with a number of other viper venom proteins which inhibit cell adhesion and platelet aggregation and are referred to as disintegrins: rhodostomin, trigramin, flavoridin, applagin, elegantin, and batroxostatin. In this study, we found that the reduction and vinylpyridylethylation of albolabrin and flavoridin decreased their platelet aggregation inhibitory activity approximately 40-50 times. It can be postulated that the higher potency of native and reduced flavoridin as compared to albolabrin depends on the substitution of the Asp of albolabrin with a Phe at the C-terminal end of the RGD in flavoridin. The activity of a synthetic C-terminal peptide derived from flavoridin (residues 35-65) containing four cysteines was about 75 times lower than that of the original flavoridin. The substitution of a pair of cysteine residues with alanines in this peptide resulted in further loss of activity. In order to identify the disulfide bonds in albolabrin, the molecule was digested consecutively by trypsin and porcine pancreatic elastase. Peptides resulting from this digestion were isolated by reverse-phase HPLC and identified by amino acid composition and mass spectrometry.(ABSTRACT TRUNCATED AT 250 WORDS)
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235
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Barlos K, Gatos D, Schäfer W. Synthesis of Prothymosinα(ProTα)—a Protein Consisting of 109 Amino Acid Residues. ACTA ACUST UNITED AC 1991. [DOI: 10.1002/anie.199105901] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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236
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Barlos K, Gatos D, Schäfer W. Synthese von Prothymosin α (ProTα), einem aus 109 Aminosäuren aufgebauten Protein. Angew Chem Int Ed Engl 1991. [DOI: 10.1002/ange.19911030516] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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237
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Böttger T, Schäfer W, Junginger T. [A prospective study for evaluating postoperative risk and long-term prognosis of mesenteric infarct]. MEDIZINISCHE KLINIK (MUNICH, GERMANY : 1983) 1991; 86:198-203, 228. [PMID: 2056985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In a prospective study on the patient material of the Surgical Clinic of the Johannes-Gutenberg-University Mainz the prognostically relevant factors in acute mesenteric vascular occlusion were investigated. From September 1, 1985 until August, 31, 1989 46 patients (24 men, 22 women) with an average age of 67.2 years were treated for an acute mesenteric vascular occlusion. Postoperatively 56.5% of the patients died. The postoperative lethality was correlated statistically significant to the period of anamnesis, the aetiology of the occlusion, the patient's age, the preoperative ASA score, and the length of the ischemically damaged bowel. The postoperative blood lactat level correlated with the outcome. Only two patients survived a second operation with a further bowel resection. One of these patients had a normal blood lactat level. The two year survival rate of the postoperative surviving patient's totalled at 70%. These results confirm the known prognostically relevant factors as well as the value of the blood lactat level in the postoperative period. They show as well, that an early second look operation depending on the intraoperative findings of the primarily operation and prior to an increase of the blood lactat level and prior to a deterioration in the patients condition is justified.
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238
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Thüroff JW, Bunke B, Ebner A, Faber P, de Geeter P, Hannappel J, Heidler H, Madersbacher H, Melchior H, Schäfer W. Randomized, double-blind, multicenter trial on treatment of frequency, urgency and incontinence related to detrusor hyperactivity: oxybutynin versus propantheline versus placebo. J Urol 1991; 145:813-6; discussion 816-7. [PMID: 2005707 DOI: 10.1016/s0022-5347(17)38459-8] [Citation(s) in RCA: 213] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Clinical efficacy and adverse effects of oxybutynin and propantheline in the treatment of symptoms related to detrusor hyperactivity were studied in a randomized, controlled, double-blind multicenter trial. Of 169 patients entered into the study 154 were evaluable for statistical analysis. Mean grade of improvement (visual analogue scale) was significantly higher with oxybutynin (58.2%) versus propantheline (44.7%) and placebo (43.4%). Mean bladder volume at first involuntary cystometric contraction was significantly increased with oxybutynin (+57.0 ml.) versus placebo (-9.7 ml.). Mean maximum cystometric bladder capacity was also significantly increased with oxybutynin (+80.1 ml.) versus placebo (+22.5 ml.). Rate of inquired possible adverse effects was significantly higher for oxybutynin (63%) versus propantheline (44%) and placebo (33%). However, only 5 patients dropped out of the study because of adverse effects (oxybutynin 2 and propantheline 3). No serious or lasting adverse effects were encountered with dryness of the mouth being the major complaint. Oxybutynin has statistically significant effects on subjective symptoms and objective urodynamic parameters in patients with detrusor hyperactivity compared to propantheline.
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239
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Binder R, Koch SW, Lindberg M, Schäfer W, Jahnke F. Transient many-body effects in the semiconductor optical Stark effect: A numerical study. PHYSICAL REVIEW. B, CONDENSED MATTER 1991; 43:6520-6529. [PMID: 9998092 DOI: 10.1103/physrevb.43.6520] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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240
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Lang E, Schäfer W, Steegmüller KW, Höckel M, Junginger T. [Perforation in Crohn disease as a complication in pregnancy]. Geburtshilfe Frauenheilkd 1991; 51:241-3. [PMID: 2055402 DOI: 10.1055/s-2007-1023713] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The manifestation of Crohn's disease with perforation in pregnancy has been described in one case only. In our case, a 25-year-old woman in the 28th week of pregnancy was admitted to our hospital with signs of an acute abdomen. Due to deterioration of the maternal and foetal situation, the child was delivered by a Caesarean section. Subsequently, exploration of the abdomen showed an ileum perforation with diffuse fibrinous peritonitis. In this case, the definitive diagnosis could not be made prior to laparotomy. The aim of surgical therapy in such cases should be the limited resection with end to end anastomosis. In diffuse peritonitis, discontinuous resection and secondary reconstruction after three to six months is preferred.
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241
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Seidl R, Mann K, Schäfer W. N-terminal amino-acid sequence of pig kidney dipeptidyl peptidase IV solubilized by autolysis. BIOLOGICAL CHEMISTRY HOPPE-SEYLER 1991; 372:213-4. [PMID: 1675855 DOI: 10.1515/bchm3.1991.372.1.213] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The N-terminal amino-acid sequence of the intrinsic membrane protein dipeptidyl peptidase IV (DP IV) was determined. The protein was isolated from pig kidney and solubilized by autolysis at pH 3.8. The first 34 amino acids were sequenced and indicated approximately 78% identity to the N-terminal sequence of rat liver DP IV.
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242
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Leo K, Shah J, Göbel EO, Damen TC, Schmitt-Rink S, Schäfer W, Köhler K. Coherent oscillations of a wave packet in a semiconductor double-quantum-well structure. PHYSICAL REVIEW LETTERS 1991; 66:201-204. [PMID: 10043536 DOI: 10.1103/physrevlett.66.201] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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243
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Stark JB, Knox WH, Chemla DS, Schäfer W, Schmitt-Rink S, Stafford C. Femtosecond dynamics of excitons under extreme magnetic confinement. PHYSICAL REVIEW LETTERS 1990; 65:3033-3036. [PMID: 10042762 DOI: 10.1103/physrevlett.65.3033] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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244
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Töpfer-Petersen E, Calvete J, Schäfer W, Henschen A. Complete localization of the disulfide bridges and glycosylation sites in boar sperm acrosin. FEBS Lett 1990; 275:139-42. [PMID: 2261983 DOI: 10.1016/0014-5793(90)81458-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Acrosin is a disulfide-bonded two-chain glycoprotein, which belongs to the serine proteinase family and which plays a central role in mammalian fertilization. The amino acid sequence of acrosin from different species has been recently derived by cDNA analysis. Boar sperm acrosin contains twelve cysteine residues forming two interchain and 4 intrachain disulfide bonds. Protein-chemical and mass-spectroscopic analyses of fragments and subfragments obtained by proteolytic and chemical degradation of the isolated protein allowed the unambiguous localization of all disulfide bridges and glycosylation points in boar acrosin. The 12 cysteines and the glycosylated asparagines in the porcine enzyme are absolutely conserved in number and position within all known acrosin sequences. Thus, the disulfide bond and glycosylation patterns outlined here are conserved during evolution and may be important for enzyme function.
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245
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Schäfer W, Uhlig G, Zaschke H, Demus D, Diele S, Kresse H, Ernst S, Wedler W. New Naphthalene Derivatives with Liquid Crystalline Glassy States. ACTA ACUST UNITED AC 1990. [DOI: 10.1080/00268949008038604] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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246
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Gal J, Yaar I, Regev D, Fredo S, Shani G, Arbaboff E, Potzel W, Aggarwal K, Pereda JA, Kalvius GM, Litterst FJ, Schäfer W, Will G. Spin-glass behavior of AFe4Al8 (A=Th,U,Np) intermetallics. PHYSICAL REVIEW. B, CONDENSED MATTER 1990; 42:8507-8516. [PMID: 9995027 DOI: 10.1103/physrevb.42.8507] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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247
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Wegener M, Chemla DS, Schmitt-Rink S, Schäfer W. Line shape of time-resolved four-wave mixing. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1990; 42:5675-5683. [PMID: 9904709 DOI: 10.1103/physreva.42.5675] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
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248
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Calvete JJ, Schäfer W, Henschen A, González-Rodríguez J. Characterization of the beta-chain N-terminus heterogeneity and the alpha-chain C-terminus of human platelet GPIIb. Posttranslational cleavage sites. FEBS Lett 1990; 272:37-40. [PMID: 2226834 DOI: 10.1016/0014-5793(90)80443-m] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Human platelet glycoprotein IIb (GPIIb) and IIIa (GPIIIa) form a Ca2(+)-dependent heterodimer, the integrin GPIIb/IIIa, which functions as the fibrinogen receptor at the surface of activated platelets. GPIIB and GPIIIa are synthesized as single polypeptides from single messages and their amino acid sequences were derived from their cDNAs. The GPIIb precursor is proteolytically processed to yield the known disulphide-bonded two-chain (GPIIb alpha and GPIIb beta) covalent structure found in mature GPIIb. Our present protein chemical and mass spectrometric analyses indicate that the GPIIb precursor is proteolytically cleaved at two or three sites, to give rise to an homogeneous alpha-chain (GPIIb 1-856) single disulphide-bonded to one of the two beta-chains, which are present in a nearly 1:1 ratio: GPIIb beta 1 (860-1008), with pyroglutamic acid as its blocked N-terminal residue: and GPIIb beta 2 (872-1008), with the already known N-terminal sequence. These results satisfy the previously observed electrophoretic size-residue: and GPIIb beta 2 (872-1008), with the already known N-terminal sequence. These results satisfy the previously observed electrophoretic size-heterogeneity of the beta-chain, confirmed the potential cleavage sites in the junction region, and indicate a probable dual proteolytic processing of GPIIb, which may be relevant to the rest of the two-chain alpha-subunits of the integrin family.
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249
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Merz P, Jansen E, Schäfer W, Will G. PROFAN-PC: a PC program for powder peak profile analysis. J Appl Crystallogr 1990. [DOI: 10.1107/s0021889890004666] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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250
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Leo K, Wegener M, Shah J, Chemla DS, Göbel EO, Damen TC, Schmitt-Rink S, Schäfer W. Effects of coherent polarization interactions on time-resolved degenerate four-wave mixing. PHYSICAL REVIEW LETTERS 1990; 65:1340-1343. [PMID: 10042239 DOI: 10.1103/physrevlett.65.1340] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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