Also flagged:Thrombomodulinproteoglycanendothelial cell surface receptorTMprotein CPC
Journal Article1991-01-01✓ 2 SnippetsBourin MC.
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Abstract)
…inhibitor antithrombin III (ATIII).…
Abstract)
…the enzyme withATIII.…
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The endothelial cell surface receptor thrombomodulin (TM) displays various anticoagulant functions: it acts as a cofactor for the activation of protein C (PC) by thrombin, prevents the activation of fibrinogen, platelets and Factor V by thrombin. TM was also shown to accelerate the inhibition of thrombin by its physiological inhibitor antithrombin III (ATIII). The studies performed on rabbit lung TM were undertaken in order to provide better understanding, along with the identification and the characterization of functional domains, to the mechanism of action of TM. On the basis of the physical and chemical properties of TM, which were compatible with those of a proteoglycan, the presence of a sulfated polysaccharide chain covalently bound to TM, constituting an acidic domain independent of the protein C activation cofactor site, was suggested. Further enzymatic and chemical characterization showed that rabbit TM was in fact a chondroitin sulfate proteoglycan. Monoclonal antibodies raised against rabbit TM and proteins known for their ability to neutralize the activity of heparin, as well as TM submitted to chondroitinase digestion were used in order to identify the role of the different structural domains of TM. Binding of thrombin to TM at a primary site on the protein part is a prerequisite for all the biological activities of TM. However, while this binding is sufficient for TM to promote the activation of PC by thrombin, the inhibition by TM of thrombin-induced fibrinogen clotting and factor V activation requires the interaction of thrombin at a secondary site with the polysaccharide chain of TM. This interaction with the polysaccharide chain (which carries a highly sulfated trisaccharide at the non-reducing terminus) leads to the inhibition of the procoagulant functions of TM-bound thrombin towards fibrinogen and factor V as well as an increased reactivity of the enzyme with ATIII. These results were rationalized in the functional model proposed for the rabbit TM-proteoglycan. An original aspect of the TM-proteoglycan resides in the fact that the chondroitin sulfate side chain brings new anticoagulant activities, in addition to the PC activation cofactor activity, to the molecule. TM is a new type of proteoglycan with important regulatory function in hemostasis, which anticoagulant properties depend on both the protein core and the polysaccharide chain.
Also flagged:idiopathic hemochromatosistardive cutaneous porphyriaPorphyria cutanea tardaporphyrinmetabolismuroporphyrinogen decarboxylase
Journal Article1991-01-01✓ 1 SnippetBuysschaert M, Verstraeten L, Novik V, Brasseur A, Donckier J, Hassoun A.
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Abstract)
…advanced that ahemochromatosisallele is implicated…
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Porphyria cutanea tarda is a disorder of porphyrin metabolism that results from a deficiency of uroporphyrinogen decarboxylase, resulting in a characteristic pattern of porphyrin excretion. Elevated serum iron values are frequently observed among patients with porphyria cutanea tarda. The hypothesis has been advanced that a hemochromatosis allele is implicated in the clinical manifestation of porphyria cutanea tarda. We report the case of a patient suffering from both idiopathic hemochromatosis and porphyria cutanea tarda. The data of the medical literature concerning such an association are discussed.
We define a standard independent unit (SIU) of heparin as that amount that, in plasma containing 1 mumol of ATIII, raises the (pseudo-)first-order breakdown constant of factor Xa by 1 min-1. These units measure all material with a high affinity for ATIII (HAM); only material above the critical chain length of 17 monosaccharide units (above critical chain length material; ACLM) catalyzes the inactivation of thrombin. An SIU of ACLM is therefore analogously defined as the amount that, in plasma containing 1 mumol of ATIII, will raise the (pseudo-)first-order breakdown constant of thrombin by 1 min-1. Of any given heparin preparation one can determine the specific HAM and ACLM activities in terms of SIU/mg. On the basis of the factor Xa and thrombin breakdown constants found in a plasma sample one can then determine the levels of HAM and ACLM. Preliminary experiments were carried out in plasma samples obtained after subcutaneous injection of unfractionated heparin (UFH) and of two types of low-molecular-weight heparin (LMWH). About three times more of UFH activity than of LMWH activity has to be injected to obtain the same levels of ACLM in the plasma. Only with the LMWHs significant amounts of BCLM are found, which rises higher and persists longer than the ACLM. We determined the course of thrombin generation in platelet-rich plasma (PRP) and in platelet-poor plasma (PPP), as well as in the PPP factor Xa generation curve and the course of prothrombin conversion. The observed inhibitions correlated much better with the levels of ACLM than with those of below critical chain length material. The difference between UFH and LMWHs can therefore not be explained in terms of antithrombin and anti-factor-Xa activity. The essential difference between UFH and LMWH appears in the feedback effect of thrombin in PRP, where thrombin generation is both inhibited and retarded by LMWH, while it is only retarded but hardly inhibited by UFH.
Also flagged:Colorectal tumorscancercarcinomasadenomascancerscolorectal tumor
Journal Article1991-01-01No SnippetsFearon ER.
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Colorectal tumors provide an excellent system in which to search for and study the genetic alterations involved in the development of a common human cancer. Data from many clinical and histopathological studies suggest that most carcinomas arise from preexisting adenomas. In addition, colorectal tumors of various stages of development can be obtained for studies of genetic alterations, unlike the situation in many other common human cancers in which only the most advanced lesions can be studied. A current view is that colorectal tumor development and progression results from the accumulation of somatic genetic alterations (mutations) in both oncogenes and tumor suppressor genes. Mutations in four to five genes may be necessary for the development of a malignant tumor; fewer changes may suffice for benign tumor formation. Although the genetic alterations often occur in a preferred sequence, the total accumulation of changes, rather than their order with respect to one another, appears to be a critical determinant of the biological properties of the tumor. Study of the genes targeted by somatic mutation in these tumors may provide insights, not only into the pathogenesis of the disease, but also into the mechanisms of origin of mutations and the potential environmental and dietary factors underlying colorectal tumor development.
Also flagged:colon carcinomachromosomecolon carcinomaschromosomesAPCtumour
Journal Article1991-01-01✓ 2 SnippetsTanaka K, Oshimura M, Kikuchi R, Seki M, Hayashi T, Miyaki M.
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Abstract)
…The APC gene on 5q and the DCC gene on 18q have been identified as potential tumour suppressor genes, whose suppression contributes to colon carcinogenesis.…
Abstract)
…5q and theDCCgene on 18q…
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Development of colon carcinomas can be associated with allelic deletions on several chromosomes, including 5q and 18q. The APC gene on 5q and the DCC gene on 18q have been identified as potential tumour suppressor genes, whose suppression contributes to colon carcinogenesis. To investigate the role of genes in these deleted regions, we have now introduced a single normal human chromosome into a human colon carcinoma cell line, COKFu, through microcell hybridization. Several clones of hybrid cells containing normal chromosome 5, and others containing normal chromosome 18, were obtained. The morphology of the hybrid cells was markedly altered: the hybrids with chromosome 5 exhibited a closely packed polygonal morphology, and the hybrid cells with chromosome 18 were flattened. The cloning efficiency of the hybrid cells in soft agar was reduced from 0.46 to 0% of that of the parental carcinoma cells, and the tumorigenicity of these hybrid cells in athymic nude mice was completely suppressed. The growth properties of the hybrid cells with chromosome 11 were not substantially changed. These results strongly suggest that the genes on normal chromosome 5 and 18 function as tumour suppressors in colon carcinogenesis.
…breast cancers using ER-P31 with anti-ER from ER-immunocytochemical assay (ER-ICA; Abbott Diagnostic Division) and radioligand dextran-coated charcoal (DCC…
Abstract)
…both ER-ICA andDCCassays was obtained.…
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A new mouse anti-oestrogen receptor (ER) monoclonal antibody, ER-P31, has been developed. Comparisons of immunohistochemical detection of ER in human breast cancers using ER-P31 with anti-ER from ER-immunocytochemical assay (ER-ICA; Abbott Diagnostic Division) and radioligand dextran-coated charcoal (DCC) assays were carried out. A total of 63 breast cancers, both ER-negative and -positive, were tested. A highly significant degree of correlation between immunostaining for ER-P31 and both ER-ICA and DCC assays was obtained. It is hoped that once ER-P31 is widely available commercially, determination of ER status in breast cancers should be routinely and economically available to all women with breast cancer. Moreover, with the introduction and implementation of a screening programme for detecting breast cancers, immunocytochemical determination of ER status in unequivocal and equivocal positive fine-needle aspirates of breast lesions can be readily performed.
Also flagged:estrogen receptorbreast carcinomaantibodyERtumordextran
Journal Article1991-01-01✓ 4 SnippetsBaddoura FK, Cohen C, Unger ER, DeRose PB, Chenggis M.
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Abstract)
…We examined the usefulness of this technique in 5-microns-thick formalin-fixed paraffin-embedded tissue sections of 66 cases of primary breast carcinoma previously assayed by dextran-coated charcoal (DCC) analysis.…
Abstract)
…with the correspondingDCCresults.…
Abstract)
…the logarithm ofDCC, the strongest correlation…
Abstract)
…were extrapolated usingDCCas the reference.…
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Monoclonal antibody to human estrogen receptor (ER) provides a useful immunohistochemical tool for the evaluation of ER content in breast carcinoma, but visual interpretation is subjective. Computer-assisted image analysis has proved effective in immunohistochemical quantitation of ER in fresh tumor imprints and cryostat sections. We examined the usefulness of this technique in 5-microns-thick formalin-fixed paraffin-embedded tissue sections of 66 cases of primary breast carcinoma previously assayed by dextran-coated charcoal (DCC) analysis. Immunohistochemistry was automated and performed on a Code-on slide stainer (Instrumentation Laboratories, Lexington, MA) using Pronase predigestion, a monoclonal antibody (ER-ICA; Abbott, Chicago, IL), and a biotin-labeled secondary antibody. Detection was achieved with an avidin-alkaline phosphatase conjugate and nitroblue tetrazolium (NBT) bromochloroindoyl phosphate (BCIP) substrate. The immunohistochemical ER staining was analyzed visually and with the CAS/200 image analyzer (Elmhurst, IL). The visual semiquantitative histologic scores (HSCORE), the automated quantitative assays including the percentage of positive nuclear areas (PNA), and the quantitative immunocytochemical scores (QIC SCORE = PNA x % of positive stain/10) were compared with the corresponding DCC results. Linear correlations were demonstrated between all immunohistochemical assays and the logarithm of DCC, the strongest correlation seen with PNA (r = 0.91). Threshold points for positive HSCORE, QIC SCORE, and PNA assays were extrapolated using DCC as the reference. ER immunodetection by PNA as compared with visual examination alone was enhanced by 18% (up to 88%) in sensitivity and 34% (up to 94%) in specificity, and the DCC concordance rate increased by 26% (up to 91%). A comparative chart extrapolating DCC from PNA was thus established.(ABSTRACT TRUNCATED AT 250 WORDS)
Also flagged:estradiol receptorsbindingbreast tumorstumorsdextrancharcoal
Journal Article1991-01-01✓ 1 SnippetRomain S, Dussert C, Martin PM.
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Abstract)
…In order to test the qualities of the 2 assays, in the same laboratory and on the same tumors, a single-point dextran-coated charcoal radioligand binding assay (RLA-DCC) and Abbott enzyme immunoassay (EIA) were used for more than two years to perform estrogen receptor determinations on cytosols from 2,134 breast cancers.…
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In order to test the qualities of the 2 assays, in the same laboratory and on the same tumors, a single-point dextran-coated charcoal radioligand binding assay (RLA-DCC) and Abbott enzyme immunoassay (EIA) were used for more than two years to perform estrogen receptor determinations on cytosols from 2,134 breast cancers. Statistical analysis of the data was performed according to the method of Passing-Bablock. The final regression curve between EIA (y) and RLA-DCC (x) was excellent y = 1.187 X fmol/mg of protein. However, from 1986 to 1988, a great variability was observed for this correlation. We report the study of this variability, which could be explained by several factors, especially calibration problems for the immunoassay kits and changes in our technical team. The binding assay appears to be more sensitive to the technicians' experience than the immunoassay. Technical points are discussed, particularly cytosol preparation and KCl presence or absence in the homogeneisation buffer. The conditions allowing for optimal correlation and routine determination fiability can therefore be defined.
Also flagged:coagulation disorderscoagulationthrombinvein thrombosispulmonary embolism
Journal Article1991-01-01✓ 2 SnippetsEngelhardt W, Blumenberg D.
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Abstract)
…(Quick, thrombin time,ATIII) should be analyzed…
Abstract)
…The substitution ofATIIIis most frequently…
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At the Institute of Anesthesiology of the University of Würzburg, blood has routinely been replaced by autotransfusion in orthopedic and surgical patients since the mid-seventies. At present the Haemonetics-Cell-Saver 3 is used to prepare autologous erythrocyte concentrates. When using this or similar, older, autotransfusion machines, the most dangerous hazard is venous air embolism during manual use despite blood centrifugation and preparation. To avoid this danger, the connecting tube to the patient must be clamped during filling of the autotransfusion bag. During autotransfusion the connecting tube between blood centrifuge and retransfusion bag must be clamped. The time loss due to this management has to be accepted. Regarding coagulation disorders, autotransfusion of large amounts of blood resembles massive transfusion with homologous blood. To maintain coagulation, hemostaseological parameters (Quick, thrombin time, ATIII) should be analyzed at the latest after replacement of half the estimated blood volume. On principle, blood components should be substituted only according to measured values. The substitution of ATIII is most frequently necessary to decrease the hazard of vein thrombosis and pulmonary embolism in these patients. The hazard of blood contamination by suctioning of operating room air should be considered. The number of operating room personnel should be as low as possible. Additionally, the suction device could be constructed to function only when necessary and not continuously. When these safety measures are followed, risks of this effective blood-saving procedure are minimized.
…patients with genetichemochromatosiswho consume excess…
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1. Carbonyl iron (2.5% w/w) in rat chow was used to induce iron loading in rat hepatocytes. 2. Acute exposure of cultured hepatocytes from control and iron-loaded rats to ethanol (25-100 mM) resulted in a significant inhibition of protein synthesis. 3. Inhibition of protein synthesis in hepatocytes from iron-loaded rats was primarily due to impaired amino acid uptake by these cells. 4. High concentrations of ethanol stimulated the rate of protein degradation by hepatocytes from iron-loaded rats. 5. Acute administration of ethanol to hepatocytes from control animals did not stimulate the absolute rates of collagen biosynthesis nor induce Type I procollagen mRNA. 6. Acute administration of ethanol did not inhibit procollagen synthesis. 7. Iron overload induced Type I procollagen mRNA and increased the absolute rates of collagen synthesis in hepatocytes. 8. These findings may be relevant for the development of hepatic fibrosis in patients with genetic hemochromatosis who consume excess ethanol.
Also flagged:biliary atresiaprimary sclerosing cholangitisfulminant hepatic failurechronic active hepatitis Bcancercyclosporine
Journal Article1991-01-01✓ 1 SnippetGordon RD, Fung J, Tzakis AG, Todo S, Stieber A, Bronsther O, Martin M, Van Thiel DH, Starzl TE.
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Text
…hemochromatosis…
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Patient and primary graft survival for 2,090 patients who received primary liver transplants at the University of Pittsburgh from 1984 through 1990 are presented. Observed (actual) 3- and 12-month patient and primary graft survival rates were compared for 3 periods: 1) January 1984 to September 1987 (cyclosporine, OKT3, and Euro-Collins preservation period); 2) October 1987 to December 1988 (University of Wisconsin solution preservation period); and 3) January 1989 to December 1990 (FK506 period). Data for results according to age group, medical urgency, and primary diagnosis are provided. In addition, estimated survivor and cumulative hazard functions (life-table method) for patient and primary graft survival out to 60 months after transplantation are presented. Overall results have improved significantly in recent experience. Most notable are the improved results seen in liver transplantation for patients with biliary atresia (especially in infants), primary sclerosing cholangitis, fulminant hepatic failure, and chronic active hepatitis B. For all but a few conditions, most of the mortality after liver transplantation occurred in the first 3 months after surgery. Less than 2% of patients were lost in each 6-month interval beyond the first 6 months after transplantation. Outcome was related to patient condition at the time of surgery. Observed survival rates at 3 and 12 months for patients called in the hospital to receive a transplant were 88.6% and 86.5%, respectively, compared with 81.9% and 73.7% for patients in critical condition. The continuing shortage of organs for transplantation, which often forces patients to wait longer for an organ than they can afford to, continues to impose a significant penalty.
Also flagged:antithrombin IIIchronic renal failuredeep vein thrombosisclotheparin
Journal Article1991-01-01✓ 1 SnippetMatsuo T, Yamada T, Matsuo M, Sakai R.
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Title)
…congenital antithrombin III (ATIII)-deficient patient with chron…
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We describe a 43-year-old male patient with congenital antithrombin III deficiency requiring hemodialysis due to extension of venous thrombus from recurrent deep vein thrombosis. During dialysis with adequate heparinization, the patient often revealed clot formation in the extracorporeal circuit resulting in unexpected discontinuation of dialysis. When either a combination of antithrombin III concentrate + heparin or the newly developed synthetic antithrombin preparation, MD805, was administered during dialysis, he could be uneventfully dialyzed with either of the two regimens.
Also flagged:coagulationalcoholmetabolismflomoxefoxacephemcephalosporin
Journal Article1991-01-01✓ 1 SnippetUchida K, Matsubara T.
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Abstract)
…The effect of flomoxef, a newly developed oxacephem antibiotic with an N-hydroxyethyltetrazolethiol (HTT) side chain, on blood coagulation and alcohol metabolism was compared with that of a series of cephalosporin antibiotics with N-methyltetrazolethiol (NMTT), thiadiazolethiol (TDT) or methylthiadiazolethiol (MTDT) side chains in position 3' of the cephalosporin nucleus known to cause hypoprothrombinemia and bleeding in patients who are malnourished, debilitated and/or of high age.…
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The effect of flomoxef, a newly developed oxacephem antibiotic with an N-hydroxyethyltetrazolethiol (HTT) side chain, on blood coagulation and alcohol metabolism was compared with that of a series of cephalosporin antibiotics with N-methyltetrazolethiol (NMTT), thiadiazolethiol (TDT) or methylthiadiazolethiol (MTDT) side chains in position 3' of the cephalosporin nucleus known to cause hypoprothrombinemia and bleeding in patients who are malnourished, debilitated and/or of high age. A disulfiram-like effect caused by inhibition of aldehyde dehydrogenase was observed for NMTT-containing antibiotics. Studies were carried out on healthy volunteers and on rats. Eight-day treatment with 2 g flomoxef i.v. once or twice daily in five and six healthy male volunteers, respectively, did not cause any significant changes in prothrombin time (PT), coagulation factors II, VII, IX or X, in hepaplastin values or fibrinogen levels, activated partial thromboplastin time (APTT), platelet counts, bleeding time, or collagen- and ADP-induced platelet aggregation. Inhibition of vitamin K epoxide reductase was observed in rats treated with flomoxef, yet to a much lesser extent than observed for cephalosporins with NMTT, TDT or MTDT side chains. This defect was quickly normalized by vitamin K injection. There were no differences between oxacephem (1-O) and cephem (1-S) compounds with respect to effects on blood clotting and platelet aggregation. Flomoxef and its side chain HTT showed no influence on alcohol metbolism.
Altogether 35 patients operated on for gastric carcinoma were examined. In the postoperative period, a study was made of alterations in gas exchange function of the lungs parallel with the parameters of the hemostatic system. It has been established that in the early postoperative period, arterial hypoxemia was associated with the maximum tension of the functioning of the hemocoagulation system. Administration of heparin in a dose of 20,000 Units/day for 10 days led to a decrease of the period of arterial hypoxemia and reduction of its intensity. This is related to the blockade of intravascular blood coagulation. The heparin dose administered does not influence the plasma content of antithrombin-III and blood fibrinolytic activity.
Also flagged:prothrombinFactor IIthrombinantithrombin IIIheparintissue plasminogen activator
Journal Article1991-01-01✓ 1 SnippetZotz RB, Mebs D, Hirche H, Paar D.
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Abstract)
…III nor theantithrombin-III-heparin complex.…
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After a bite by the aglyphous red-necked keelback snake Rhabdophis subminiatus a complete defibrinogenation syndrome with severe hemorrhagic diathesis developed in a 25-year-old man. In vitro studies showed that the venom gland extract of the snake contains a very active prothrombin (Factor II) activator. The thrombin generated is inhibited neither by antithrombin III nor the antithrombin-III-heparin complex. The venom gland extract stimulated also the tissue plasminogen activator; however, it did not cause direct activation of plasminogen, protein C, Factor X or direct degradation of fibrinogen.
Also flagged:nephrotic syndromebeta-thromboglobulinbetaplatelet factor 4PF4fibrinogen
Journal Article1991-01-01✓ 2 SnippetsDe Mattia D, Penza R, Giordano P, Di Bitonto G, Altomare M, Del Vecchio GC, Schettini F.
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Abstract)
…and protein C (ATIII:Ag and PC:Ag), and…
Abstract)
…than 0.05) whereasATIIIvalues were significantly…
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The in vivo activation of the hemostatic system was evaluated in 14 children (4-13 years old) with nephrotic syndrome at different stages of the disease. The blood platelet count, beta-thromboglobulin (beta-TG), platelet factor 4 (PF4), fibrinogen, the coagulation inhibitors antithrombin III and protein C (ATIII:Ag and PC:Ag), and D-dimers were determined. Platelet number was significantly higher at the onset of the disease than in the next stages (p less than 0.05). beta-TG, PF4 and fibrinogen were significantly increased as compared with controls at the onset (p less than 0.001) and decreased progressively during the course of the disease without reaching the control values. Blood coagulation inhibitors behaved differently; PC was higher in patients than in controls at all stages (p less than 0.05) whereas ATIII values were significantly decreased at the onset (p less than 0.05), but increased during the course the disease (p less than 0.01). No changes were observed in the D-dimer plasma levels. These data suggest that the thrombotic risk in nephrotic syndrome is particularly evident at the onset of the disease, and appears to be due mainly to changes in platelet number and function, and to increased fibrinogen levels rather than to alterations of plasma anticoagulant factors.
Also flagged:Steroid receptorsteroid receptorsdextranestradiolbindingdiethylstilbestrol
Journal Article1991-01-01✓ 1 SnippetPiffanelli A, Giovannini G, Pelizzola D, De Bortoli M, Catozzi L, Giganti M.
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Abstract)
…The standardized DCC method is the most common and recognized (Food and Drug Administration) procedure for quantifying hormone receptor in human cancer.…
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An Italian Committee for the quality assessment of steroid receptor assay was instituted in 1979; the number of laboratories participating in this program increased from 7 in 1979 to 43 in 1989. The Italian program in collaboration with EORTC (European Organization Research and Treatment of Cancer) initiatives, utilizes as working standards lyophilized samples that tolerate prolonged storage at 4 degrees C. The national representatives agreed, according to EORTC, that all laboratories would perform, for measurement of steroid receptors, the dextran coated charcoal (DCC) method using the same concentration of radioactive ligands (3-H-estradiol, 3-H-ORG-2058) and would determine the non-specific binding with the same compounds (diethylstilbestrol and ORG-2058). The computation method is a potential source of interlaboratory variation; the multipoint Scatchard analysis, though difficult to apply for receptor problems, is the most widely used approach at present. The standardized DCC method is the most common and recognized (Food and Drug Administration) procedure for quantifying hormone receptor in human cancer. Since new technologies are being introduced (receptor enzyme immunoassay, EIA), adequate programs of quality assessment are required; in general, it has demonstrated an excellent correlation between radioligand binding assay (DCC) and immunochemical assay (EIA). Other prognostic factors, such as proteins produced by oncogenes and growth factors of the malignant cells have become more important. Some of these factors, as well as estrogen receptor status, seem the major determinants of recurrence after the first treatment.
Also flagged:toxemiacoagulationthrombinantithrombin IIITATalpha 2-antiplasmin
Journal Article1991-01-01✓ 1 SnippetTerao T, Maki M, Ikenoue T, Gotoh K, Murata M, Iwasaki H, Shibata J, Nakabayashi M, Muraoka M, Takeda Y.
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Abstract)
…decreases of theATIIIlevel were observed…
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The hypercoagulable state in patients with toxemia of pregnancy was investigated in comparison with normal pregnant women using new coagulation parameters, mainly thrombin-antithrombin III (TAT) complexes, alpha 2-antiplasmin-plasmin complexes (PIP), and D-dimer FDP. When the patients were categorized by the classification of the WHO Study Group (1985), significant increases of TAT complexes and alpha 2-PIP complexes with decreases of the ATIII level were observed in the groups with preeclampsia and severe gestational hypertensive disease as compared to normal pregnant women. A significant increase of D-dimer FDP was observed in a group with severe gestational hypertensive disease. Additionally, the relationship between clinical signs and the hypercoagulable state in the patients was analyzed using canonical correlation analysis as a multivariate analysis. The clinical signs and coagulation parameters had a significantly high correlation of lambda 1 = 0.7219, p less than 0.01. The results showed that clinical signs were associated with simultaneous coagulation abnormalities. The indices obtained from the results of canonical correlation analysis, which were called the clinical index and the coagulation index, should be useful in evaluating the efficacy of anticoagulation therapy.
Also flagged:oestrogen receptorsbindingbreast cancertumoursdextrancharcoal
Journal Article1991-01-01✓ 2 SnippetsRomain S, Dussert C, Martin PM.
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Abstract)
…tumours, a single-point dextran-coated charcoal radioligand binding assay (RLA-DCC…
Abstract)
…DCC) and the Abbott enzyme immunoassay (EIA) were used to perform oestrogen receptor determinations on cytosols from 1841 breast cancers…
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To test the qualities of two assays in the same laboratory on the same tumours, a single-point dextran-coated charcoal radioligand binding assay (RLA-DCC) and the Abbott enzyme immunoassay (EIA) were used to perform oestrogen receptor determinations on cytosols from 1841 breast cancers over a 2-year period. Statistical analysis of the data was performed by the Passing-Bablock linear regression technique. The final regression curve between EIA (y) and RLA-DCC (x) yielded y = 1.187 x fmol/mg of protein. However, a high variability in this correlation was observed from 1986 to 1988. This variability could be explained by calibration problems in the immunoassay kits and changes in our technical team. The binding assay appears to be more sensitive to the technicians' experience than the immunoassay. Other technical points are discussed, particularly cytosol preparation and KCl presence or absence in the homogenisation buffer. Finally, the Passing-Bablock and the least squares regression procedures are compared. The conditions allowing optimal correlation and routine determination reliability are defined and the correlation variability is discussed.
Also flagged:coagulation-fibrinolysisuremiacoagulationalpha-2-plasminplasmin
Journal Article1991-01-01✓ 1 SnippetNakamura Y, Chida Y, Tomura S.
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Abstract)
…ATIIIactivity was significantly…
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Thirty-three patients with chronic uremia on regular hemodialysis treatment (RDT) have been studied to determine whether coagulation and fibrinolysis are enhanced or not. We examined predialysis values of coagulation and fibrinolysis parameters including alpha-2-plasmin inhibitor-plasmin complex (alpha 2PIC), a good index of in vivo plasmin production, and cross-linked fibrin degradation products (XL-FDP), an index of fibrinolysis secondary to coagulation. Fibrinogen was significantly higher (p less than 0.001) in RDT patients than in normal controls. ATIII activity was significantly lower in RDT patients than in normal controls (p less than 0.001). Plasminogen activity and alpha-2-plasmin inhibitor (alpha 2PI) activity were significantly lower (p less than 0.001) in RDT patients than in normal controls. Alpha 2PIC and XL-FDP were both significantly higher (p less than 0.001) in RDT patients than in normal controls. XL-FDP was inversely correlated with alpha 2PI (r = -0.486, p less than 0.01) and positively correlated with alpha 2PIC (r = 0.646, p less than 0.001). These results suggest that coagulation and fibrinolysis are enhanced in RDT patients and that the enhanced fibrinolysis is mainly due to fibrinolysis secondary to coagulation.
…In colorectal carcinoma, p53 and DCC alterations were detected in 100% of metastases, and sequential accumulation of allelic losses on chromosomes 13q, 14q, and 18q in the process of metastasis was observed.…
Abstract)
…carcinoma, p53 andDCCalterations were detected…
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Inactivation of tumor suppressor genes is now believed to play an important role in various progression stages of human cancers. To clarify the possible involvement of tumor suppressor gene inactivation in the acquisition of metastatic potential in lung and colorectal carcinoma cells, we examined various genetic alterations in both primary tumors and metastases obtained from patients with lung and colorectal carcinomas. In lung carcinoma, loss of heterozygosity on chromosomes 3p, 13q, and 17p is a common genetic alteration, and both RB and p53 genes are inactivated as a result of chromosome 13q and 17p losses. In some cases, allelic loss on chromosome 11p and amplification of myc family oncogenes occur during tumor progression. In colorectal carcinoma, p53 and DCC alterations were detected in 100% of metastases, and sequential accumulation of allelic losses on chromosomes 13q, 14q, and 18q in the process of metastasis was observed. These results indicate that a subset of tumor suppressor genes is involved in metastasis of lung and colorectal carcinomas.
Journal Article1991-01-01✓ 1 SnippetHalbert CL, Demers GW, Galloway DA.
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Abstract)
…Infection of HFE…
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The contribution of the E6 and E7 open reading frames of human papillomavirus type 6b (HPV6b) and HPV16 to immortalization of human keratinocytes was evaluated by using amphotropic recombinant retroviruses. The HPV16 E7 gene could immortalize primary human keratinocytes without the cooperation of the viral E6 gene; however, E6 was able to contribute significantly to the efficiency of the E7 immortalizing function. Infection of HFE cells with retroviruses carrying the 16E6, 6bE6, or 6bE6E7 open reading frame did not result in immortalization.
Also flagged:colorectal cancercancerfamilial polyposis colitumoradenomaadenocarcinoma
Journal Article1991-01-01✓ 2 SnippetsShirasawa S, Yanagawa Y, Sasazuki T.
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Abstract)
…tumor suppressor genes such as p53 and DCC…
Abstract)
…as p53 andDCCgenes, as well…
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The inherited cancer-inducing disease familial polyposis coli (FPC) provides an excellent model not only for studying tumor progression in colorectal cancer but also for elucidating molecular mechanisms in general oncogenesis. This paper reviewed recent remarkable progresses of molecular mechanisms in colorectal tumorigenesis. This is concerned with the various kinds of genetic alterations that accumulate in the development from normal mucosa to adenoma, and then to adenocarcinoma in comparison with FPC and sporadic cases. This review included also information on the localization of FPC major gene. These observations indicate that in cases of colorectal tumorigenesis several genetic alterations may be involved, including activation of K-ras gene, deregulated expression of c-myc gene or c-fos gene and inactivation of tumor suppressor genes such as p53 and DCC genes, as well as the loss of heterozygosity. The observation suggest that adenomas will have undergone several gene or chromosome mutations before reaching to the fully malignant state. Therefore, DNA diagnosis for colorectal tumors in the clinical level may contribute to more accurate prognosis and better results for further therapy.
Also flagged:breast carcinomahormonal receptorARbreast tumorEstrogen ReceptorER1
Journal Article1991-01-01No SnippetsSimone G, Paradiso A, Barletta A, Bellomo E, Caponio M, Sapia MG, Rella G, Tommasi S.
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Several AA, utilizing the biochemical method (DCC) showed the presence or absence of hormonal receptor in either synchronous or metachronous metastatic nodes (N) can reproduce the receptor assessment (AR) of the primary breast tumor (T). We evaluated the AR in T and in synchronous N, by using two morphological methods, immunocytochemical and histofluorescent, to detect the nuclear Estrogen Receptor (ER1) and cytoplasmic sites of the II type (ER2 and PgR2). We studied 50 patients who underwent radical mastectomy for breast cancer N+. In this series we founded a high correlation between AR in T and in N: 82% for ER1, 94% for ER2, and 92% for PgR2. Also we observed 4 cases (2 ER1 and 2 PgR2) which presented the receptor in N only. These data are comparable to results obtained with the DCC method and confirm the opportunity to perform also morphological techniques to evaluate AR in breast cancer to take into consideration also cellularity and tumor heterogeneity informations.
Also flagged:Estrogen receptorbreast cancerdextranERtamoxifenER receptor
Journal Article1991-01-01✓ 1 SnippetAndersen J, Thorpe SM, Rose C, Christensen I, Rasmussen BB, Poulsen HS.
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…TheDCCassay showed an…
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Estrogen receptor (ER) was estimated immunohistochemically in formalin-fixed and paraffin-embedded tissue from the primary breast cancer in 349 postmenopausal patients with a high risk of recurrence and compared with the results of dextran-coated charcoal assay. There was a highly significant correlation between the ER classification obtained by the two methods (p less than 10(-6)). Patients ER positive according to immunohistochemical estimate had a significantly longer disease-free survival (p less than 0.001) and survival (p less than 0.001) than ER negative patients. The DCC assay showed an advantage of ER positive patients of the same magnitude. The patients, who were followed for a median of 86 months, were a subset of 1,700 patients participating in the Danish Breast Cancer Cooperative Group's randomized trial of adjuvant tamoxifen (TAM) treatment. In the presently analyzed subset of patients there were no statistically significant difference in disease-free survival (p = 0.52) or survival (p = 0.54) between patients who received adjuvant TAM and the controls. The same was true for receptor-defined subgroups regardless if the ER receptor was estimated in paraffin-embedded tissue or by the dextran-coated charcoal method. The analyzed subset might have been too small for demonstrating a positive effect of adjuvant TAM treatment.
The LNCaP-FGC (fast growing colony) cell line, a subline derived from the LNCaP cell line, shares all the main characteristics, including its androgen sensitivity, described for the parental line. A number of sublines originating from the FGC line were characterized with respect to their response to steroid-depleted medium and to the synthetic androgen R1881. The growth of FGC cells in DCC medium with 0.1 nM R1881 was stimulated 2-3-fold compared to growth in DCC medium only. FGC cells that were continuously grown in DCC medium did not die, but their growth rate was clearly slowed down, and the cells remained responsive to androgen. These cells, therefore, have the androgen-sensitive, rather than the androgen-dependent phenotype. As cells of the subline FGC-JB could not be maintained in DCC medium, these cells better represent the androgen-dependent cell type. In contrast to the FGC line, cells of the R line, grew equally well in medium with complete or DCC serum. Under none of these culture conditions, R cells could significantly be stimulated further with R1881. Further analysis of the LNCaP-FGC sublines should provide valuable information concerning the development of androgen resistance in human prostate cancer.
Recent experimental work has identified a novel intracellular binding site for the synthetic progestin, Gestodene, that appears to be uniquely expressed in human breast cancer cells. Gestodene is shown here to inhibit the growth of human breast cancer cells in a dose-dependent fashion, but has no effect on endocrine-responsive human endometrial cancer cells. Gestodene induced a 90-fold increase in the secretion of transforming growth factor-beta (TGF-beta) by T47D human breast cancer cells. Other synthetic progestins had no effect, indicating that this induction is mediated by the novel Gestodene binding site and not by the conventional progesterone receptor. Furthermore, in four breast cancer cell lines, the extent of induction of TGF-beta correlated with intracellular levels of Gestodene binding site. No induction of TGF-beta was observed with the endometrial cancer line, HECl-B, which lacks the Gestodene binding site, but which expresses high levels of progesterone receptor. The inhibition of growth of T47D cells by Gestodene is partly reversible by a polyclonal antiserum to TGF-beta. These data indicate that the growth-inhibitory action of Gestodene may be mediated in part by an autocrine induction of TGF-beta.
Transcription of the Saccharomyces cerevisiae metallothionein gene CUP1 is induced in response to high environmental levels of copper. Induction requires the ACE1 gene product, which binds to specific sites in the promoter region of the CUP1 gene. In this study, we found that deleting the entire coding sequence of the ACE1 gene resulted in a decrease in basal-level transcription of CUP1 to low but detectable levels and conferred a copper-sensitive phenotype to the cells. We have isolated a gene, designated ACE2, which when present on a high-copy-number plasmid suppresses the copper-sensitive phenotype of an ace1-deletion strain. The presence of multiple copies of the ACE2 gene enhanced expression of an unlinked CUP1-lacZ fusion integrated in the yeast genome and resulted in an increase in the steady-state levels of CUP1 mRNA in an ace1-deletion background. A large deletion of the coding region of the genomic copy of ACE2 resulted in a decrease in steady-state levels of CUP1 mRNA, indicating that ACE2 plays a role in regulating basal-level expression of CUP1. The ACE2 open reading frame encodes a polypeptide of 770 amino acids, with putative zinc finger structures near the carboxyl terminus. This protein is 37% identical to the SWI5 gene product, an activator of HO gene transcription in S. cerevisiae, suggesting that ACE2 and SWI5 may have functional similarities.
Also flagged:degradation2,4-trichlorobenzenecarbon-dichlorobenzene,4-trichlorobenzenedioxygenase
Journal Article1991-01-01No Snippetsvan der Meer JR, van Neerven AR, de Vries EJ, de Vos WM, Zehnder AJ.
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Pseudomonas sp. strain P51 is able to use 1,2-dichlorobenzene, 1,4-dichlorobenzene, and 1,2,4-trichlorobenzene as sole carbon and energy sources. Two gene clusters involved in the degradation of these compounds were identified on a catabolic plasmid, pP51, with a size of 110 kb by using hybridization. They were further characterized by cloning in Escherichia coli, Pseudomonas putida KT2442, and Alcaligenes eutrophus JMP222. Expression studies in these organisms showed that the upper-pathway genes (tcbA and tcbB) code for the conversion of 1,2-dichlorobenzene and 1,2,4-trichlorobenzene to 3,4-dichlorocatechol and 3,4,6-trichlorocatechol, respectively, by means of a dioxygenase system and a dehydrogenase. The lower-pathway genes have the order tcbC-tcbD-tcbE and encode a catechol 1,2-dioxygenase II, a cycloisomerase II, and a hydrolase II, respectively. The combined action of these enzymes degrades 3,4-dichlorocatechol and 3,4,6-trichlorocatechol to a chloromaleylacetic acid. The release of one chlorine atom from 3,4-dichlorocatechol takes place during lactonization of 2,3-dichloromuconic acid.
Also flagged:NucleotidekatEribosomebindingamino acidRNA polymerase
Journal Article1991-01-01No Snippetsvon Ossowski I, Mulvey MR, Leco PA, Borys A, Loewen PC.
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A 3,466-bp nucleotide sequence containing the katE gene of Escherichia coli has been determined. An open reading frame of 2,259 bp was found and was preceded by a potential ribosome-binding site. The predicted N-terminal sequence agreed with the sequence determined by direct amino acid sequencing, and the predicted direction of transcription was confirmed by expression of the gene cloned in both directions behind a T7 promoter. The start site of transcription was determined to be 127 bp upstream from the start of the open reading frame, and a potential RNA polymerase-binding site similar to a sequence preceding the xthA gene, which is also controlled by the KatF protein, was identified. The predicted sequence of the 753-amino-acid protein was compared with known sequences of other catalases, revealing significant similarity to the shorter catalases, including the residues in the putative active site and residues involved in heme binding.
Also flagged:estrogenprogesterone receptorsmetastatic breast carcinomaestradiolalbuminfluorescein
Journal Article1991-01-01No SnippetsMasood S.
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Estrogen and progesterone receptors were studied in fine-needle aspiration biopsy specimens of 56 patients with primary, recurrent, or metastatic breast carcinoma. The ligands, 17 B-estradiol-6-carboxymethyloxine-bovine serum albumin fluorescein isothiocyanate (FITC-BSA estradiol) and hydroxyprogesterone hemisuccinate bovine serum albumin tetramethyl rhodamine isothiocyanate (TMRITC-BSA progesterone), were used in the fluorescent cytochemical method. The findings obtained from the aspirated cells with the use of the fluorescent cytochemical technique were compared with results obtained from the cell population of the same tumor after removal with the use of both the fluorescent cytochemical technique and the biochemical dextran-coated charcoal (DCC) assay. For the needle aspirates, there was 89% concordance for estrogen receptor and 86% concordance for progesterone receptor between biochemical and cytochemical results. A high degree of correlation was also demonstrated between fine-needle aspirates and imprint preparations with the use of the cytochemical technique. This study suggests that the fluorescent cytochemical technique is an effective tool in assessment of estrogen and progesterone receptor content in fine-needle aspirates of primary and metastatic breast cancer. The fluorescent cytochemical technique can be performed easily at community hospitals and is well suited for specimens of insufficient size for biochemical assay.
Also flagged:thrombinhemostasiswound healingatherosclerosistyrosinecell adhesion
Journal Article1991-01-01✓ 1 SnippetBar-Shavit R, Sabbah V, Lampugnani MG, Marchisio PC, Fenton JW, Vlodavsky I, Dejana E.
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…of thrombin-antithrombin III (ATIII) complexes and by…
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Thrombin, in addition to its central role in hemostasis, possesses diverse cellular bioregulatory functions implicated in wound healing, inflammation, and atherosclerosis. In the present study we demonstrate that thrombin molecules modified either at the procoagulant or catalytic sites induce endothelial cell (EC) adhesion, spreading, and cytoskeletal reorganization. The most potent adhesive thrombin analogue (NO2-alpha-thrombin) was obtained by nitration of tyrosine residues. The cell adhesion promoting activity of NO2-alpha-thrombin was blocked upon the formation of thrombin-antithrombin III (ATIII) complexes and by antiprothrombin antibodies, but was unaffected by hirudin. Arg-Gly-Asp-containing peptides, fully inhibited EC adhesion to NO2-alpha-thrombin, while synthetic peptides corresponding to thrombin "Loop B" mitogenic site and the thrombin-derived chemotactic fragment "CB67-129", were uneffective. Immunofluorescence studies indicated that EC adhesion to NO2-alpha-thrombin was followed by cell spreading, actin microfilament assembly, and formation of focal contacts. By the use of specific antibodies, the vitronectin (vn) receptor (alpha v beta 3) was found to be localized in clusters upon cell adhesion to NO2-alpha-thrombin. An anti alpha v beta 3 antibody blocked EC adhesion and spreading while antifibronectin (fn) receptor (alpha 5 beta 1) antibodies were uneffective. While native thrombin exhibited a very low cell attachment activity, thrombin that was incubated at 37 degrees C before coating of plastic surfaces induced EC attachment and spreading. We propose that under certain conditions the naturally hindered RGD domain within thrombin is exposed for interaction with alpha v beta 3 on EC. This in turn promotes cell adhesion, spreading, and reorganization of cytoskeletal elements, which may altogether contribute to repair mechanisms in the disturbed vessel wall. This study defines a new biological role of thrombin and characterizes a new recognition mechanism on EC for this molecule.
Also flagged:ecto-5'-nucleotidaseCD73breast carcinomaphosphatidylinositolmembranelymphocyte differentiation antigen
Journal Article1991-01-01No SnippetsKrüger KH, Thompson LF, Kaufmann M, Möller P.
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Ecto-5'-nucleotidase (ecto-5'-NT) is a phosphatidylinositol anchored membrane structure recently defined as the lymphocyte differentiation antigen CD73. Using CD73 (1E9.28.1) monoclonal antibody, normal mammary gland and breast carcinoma were immunohistochemically investigated for ecto-5'-NT expression. In normal breast epithelium, CD73 was differentially expressed in lobular, ductal and myoepithelial cells and was most frequently detected in the myoepithelial compartment. The glandular stroma contained fibrocytes, a subset of which was also CD73-positive. Among 102 unselected breast carcinoma primary lesions, only 9 contained CD73-positive tumour cells, whereas in 95 cases, stromal fibroblasts and fibrocytes showed variable degrees of CD73 expression. The extent of stromal CD73 expression correlated positively with the estrogen receptor (ER) status of the tumour (P less than 0.038). We conclude that ecto-5'-NT-expression reflects a still unknown state of activity of normal breast epithelium which is lost in the majority of carcinomas derived therefrom. It may also be indicative of some functional activity of stromal fibroblasts which is significantly enhanced in ER-positive carcinomas.
Also flagged:INT2HST1breast cancermammary carcinomachromosomeband localisation
Journal Article1991-01-01No SnippetsBorg A, Sigurdsson H, Clark GM, Fernö M, Fuqua SA, Olsson H, Killander D, McGurie WL.
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The human proto-oncogene INT2 (homologous to the mouse INT2 gene, implicated in proviral induced mammary carcinoma) has been mapped to chromosome 11q13 and found to share band localisation with, among others, the HST1 proto-oncogene. Both genes are members of the fibroblast growth factor family. In the present study, coamplification (2-15 copies) of the INT2/HST1 genes was found in 27 (9%) of 311 invasive human breast carcinomas using slot blot and Southern blot analyses. Amplification was not correlated to tumour size, axillary lymph node status or stage of disease, neither to patient age nor menopausal status. However, 26 (96%) of the 27 amplified tumours were, often strongly, Oestrogen receptor positive compared to 65% of the unamplified cases (P = 0.001). These findings are in sharp contrast to the strong correlations of HER-2/neu proto-oncogene amplification with advanced stage and steroid receptor negativity, previously observed in the same series of tumours. Patients with INT2/HST1 amplified breast cancer had a significantly shorter disease-free survival compared to those with unamplified genes (P = 0.015, median follow up 45 months). This correlation was confined to node-negative patients and persisted in multivariate analysis. No significant correlation to survival from breast cancer was found. It is concluded that amplification of the 11q13 region in breast cancer occurs in a particular subset of aggressive tumours, quite different from that identified by HER-2/neu amplification. It still remains to be shown that the selection for amplified genes at 11q13 is due to the activity of INT2, HST1 or yet another, still unidentified, neighbouring gene. However, the results are potentially of clinical value in separating a group of node-negative breast cancer for more intense treatment.
Also flagged:hereditary hemochromatosisHHiron overload diseaseironHLAmetabolic disorder
Journal Article1991-01-01✓ 1 SnippetBryan CF.
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…product of thehemochromatosisgene is unknown,…
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Hereditary hemochromatosis (HH), an iron overload disease caused by unregulated intestinal iron absorption, is a recessive HLA-linked disease. HH is the most common inherited metabolic disorder with one of every 400 to 500 individuals having both genes and being likely to develop the disease. Thus, although the product of the hemochromatosis gene is unknown, its mode of inheritance allows HLA-genotyping of the proband and his/her siblings to be highly predictive of the genetic propensity to develop the clinical features of HH. In view of the known immunoregulatory properties of iron and its binding proteins, it is important to determine if the high levels of storage iron in HH influence the immunosurveillance network in HH patients and whether that has any clinical relevance. We have defined certain alterations of the effector cells of the cellular arm of the immune system and have studied a patient with HH who had specific immune alterations, including delayed cutaneous-type hypersensitivity anergy, and was diagnosed with poorly differentiated adenocarcinoma of the stomach four years after his HH diagnosis. Those findings are consistent with the interpretation that in certain clinical situations of elevated body iron stores, the immunoregulatory balance or environment may be tipped in favor of growth and development of cancer cells.
Also flagged:estrogen-receptorsacute myeloid leukemiaAMLERdextranESR
Journal Article1991-01-01✓ 1 SnippetHatfill SJ, Brusnicky J, Fester E.
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…were confirmed byDCCin one patient…
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The peripheral and bone marrow blast cells of twenty patients newly-diagnosed as acute myeloid leukemia (AML), subtypes M1-M5, were analysed for the presence of estrogen-receptors by ER-ICA immunocytochemistry and dextran-coated charcoal cytosolic (DCC) assay. Two patients demonstrated myeloblasts with nuclear staining patterns consistent with the presence of estrogen-receptors. The positive immuno-staining results were confirmed by DCC in one patient with AML, subtype M4. This patient demonstrated an unusual myeloblast karyotype with a reciprocal translocation t(6;11)(q27;q23.3) involving the designated locus of the ESR gene on chromosome 6 (6q24-qter). The abnormal juxtaposition of DNA control elements close to the promoter of the ESR gene may be one mechanism by which aberrant synthesis of estrogen-receptor protein can occur to provide a growth advantage for leukemia cell clones.
Also flagged:albumin11-dehydrothromboxane B2tyrosine methyl esterdehydrodextranpolyethylene glycol
Journal Article1991-01-01No SnippetsMucha I, Riutta A, Vapaatalo H.
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The determination of 11-dehydrothromboxane B2 (11-dehydro-TXB2) from unextracted human urine was studied by means of a specific radioimmunoassay based on the use of the 125I-labelled tyrosine methyl ester derivative of 11-dehydro-TXB2 as radioligand. The assay was evaluated in various incubation media by either dextran-coated charcoal (DCC) or polyethylene glycol (PEG) separation. Both the non-specific and the specific binding showed high variation in different assay media with DCC separation but with the use of PEG separation, however, the non-specific binding was constant. The verification tests carried out in both separation systems revealed a high variation of equilibrium with the individual samples. The albumin content of urine is proposed to be one important factor underlying poor reliability of direct radioimmunoassay. Both the immunoreactivity profiles observed after HPLC separation and the apparent 11-dehydro-TXB2-like immunoreactivity values determined by direct radioimmunoassay demonstrated that the unextracted urine contained a high ratio of interfering materials. It is concluded that efficient purification of human urine before determination is essential when this type of 125I-labelled radioligand is employed in radioimmunoassay.
A genetic variant of antithrombin with impaired heparin cofactor activity was identified in 4 members of a French family. Both the variant and normal antithrombin component were purified by affinity chromatography on heparin Sepharose. Reverse phase peptide mapping revealed a single altered peak when tryptic digests of both antithrombins were compared. After further purification of the aberrant peptide, amino acid analysis indicated a substitution of 41 Leu----Pro (antithrombin Basel). This result was confirmed by liquid secondary ion mass spectrometry which gave a measured mass of 816.4655 Da for the new peptide compared to a calculated mass of 800.3579 Da for the normal peptide and 816.4579 for the Leu----Pro substitution.
Also flagged:ischemic heart diseasehemostasisfibrinolysisplatelet aggregationcoronary heart diseasemyocardial infarction
Journal Article1991-01-01✓ 1 SnippetKovalenko VM, Shunkova EI, Gol'dberg GA, Karagaeva LG, Shlafer ID, Epifantseva NN.
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…the level ofantithrombin-IIIrises and initial…
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A study was made of hemostasis, fibrinolysis and platelet aggregation at rest and exercise in 32 healthy persons and 35 patients suffering from coronary heart disease (CHD) with a history of myocardial infarction that had occurred 2-3 months before. It has been discovered as a result that in healthy persons at exercise, the blood coagulation system and fibrinolysis are activated, the level of antithrombin-III rises and initial platelet aggregation decreases. In patients with CHD at exercise, hypercoagulation, deceleration of fibrinolysis, and the decline of the level of AT-III are detectable, with platelet aggregation being enhanced.
Also flagged:organometallic complexesacylsynthesisdienesiron, β-unsaturated
Journal Article1991-01-01No SnippetsFatiadi AJ.
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The objective of this review is to provide a current overview of the rapidly developing chemistry of organometallic complexes and particularly organoiron complexes useful in asymmetric and stereoselective reactions. Also covered are stereoselective reactions of α, β-unsaturated acyl ligands bound to the chiral auxiliary [(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>) Fe(CO)(PPh<sub>3</sub>)] and new applications of organoiron complexes in the synthesis of natural products. The mechanistic aspects and stabilizing effects of the Fe(CO)<sub>3</sub> group for alkenes or conjugated dienes are discussed. A brief summary of recent work on the special role of iron in biological reactions is also included.