Journal of clinical pathology. Supplement (Association of Clinical Pathologists)最新文献

{"title":"Enzyme kinetics.","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":75995,"journal":{"name":"Journal of clinical pathology. Supplement (Association of Clinical Pathologists)","volume":"4 ","pages":"97-8"},"PeriodicalIF":0.0,"publicationDate":"1970-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1176293/pdf/jcpsuppasso00002-0103.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16095208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative assay of enzymes in tissues.","authors":"E A Burgess, B Levin","doi":"10.1136/jcp.s1-4.1.37","DOIUrl":"https://doi.org/10.1136/jcp.s1-4.1.37","url":null,"abstract":"There are two main groups of conditions in which the determination of enzyme activities in tissues is necessary or desirable. They are (a) primary defects of enzyme synthesis and (b) alterations of enzyme activity secondary to damage of the cell. Since the time of Garrod, hereditary metabolic disorders have been recognized to be due to a defect of one or perhaps more enzymes, which may have farreaching metabolic consequences and produce multiple biochemical and other abnormalities. This communication is confined to enzyme assays using tissues from organs such as liver, kidney, or gastrointestinal mucosa and including the leucocytes of the blood. It excludes the examination of blood plasma, the enzymes of which are, of course, not synthesized there, but accumulate by leakage from the organs it bathes or from degradation of red and white blood cells. A general review of methods of enzyme assay is not attempted, but the principles of the methods used for individual enzyme assays are *emphasized. Selection has been based on the special factors which must be taken into account in this field, eg, the limited amount of material available so that the sensitivity of a method is important, and the fact that tissues contain a mixture of enzymes as well as many different substrates. The methods of assay available for pure enzymes are not always applicable to a crude tissue homogenate.","PeriodicalId":75995,"journal":{"name":"Journal of clinical pathology. Supplement (Association of Clinical Pathologists)","volume":"4 ","pages":"37-42"},"PeriodicalIF":0.0,"publicationDate":"1970-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1136/jcp.s1-4.1.37","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16376323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enzyme assays in malignant disease.","authors":"C B Cameron","doi":"10.1136/jcp.s1-4.1.80","DOIUrl":"https://doi.org/10.1136/jcp.s1-4.1.80","url":null,"abstract":"Although cancer diagnosis remains almost exclusively morphological, withhistological examination thelynch pin,there aresituations inwhichother techniques, suchasenzymeassays, mayprovide information ofclinical value. Itis,however, disappointing thatsomuchoftheincrease inknowledge ofthebiochemical properties oftumours has proved tobenonspecific, andtherefore oflimited diagnostic value.Nevertheless, tumourshave occasionally produced anunusual isoenzyme, an observation ofconsiderable biological anddiagnostic interest. Assaysofnormally occurring enzymesinserummay alsoyieldinformation of clinical valueincircumstances wherethelackof specificity isnotimportant; thus, whilst notindicatingthenature ofatumour, theymaynevertheless provide anindication ofitsactivity, ofitsresponse totreatment, orofthesite ofmetastases. Elevation ofserumenzymes bytumours maybe duetoleakage fromthetumourorfromadjacent normaltissue damagedbytheneoplasm. Serum enzymelevels mayalsobeinfluenced less directly, forexample whenthere isassociated haemolysis. Usually morethanoneofthese factors isoperative, asemphasized inthefollowing discussion. SerumAlkaline Phosphatase (EC3.1.3.1.) Assayofthis enzymecontinues tobeofgreat value inthedetection oflesions inliver andbone. Different isoenzymes havebeendemonstrated by various techniques inliver, bone,intestine, andplacenta. Somedegree ofdiscrimination ispossible onthe basis ofureainhibition, heatstability andelectrophoresis, therelative merits ofthelatter onvarious mediabeing discussed elsewhere inthis symposium byWiemeandDemeulenaere (p.51);however,","PeriodicalId":75995,"journal":{"name":"Journal of clinical pathology. Supplement (Association of Clinical Pathologists)","volume":"4 ","pages":"80-4"},"PeriodicalIF":0.0,"publicationDate":"1970-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1136/jcp.s1-4.1.80","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16041271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enzyme assays in the management of pregnancy.","authors":"P Curzen","doi":"10.1136/jcp.s1-4.1.90","DOIUrl":"https://doi.org/10.1136/jcp.s1-4.1.90","url":null,"abstract":"The occurrence of increased serum enzyme activity in patients with diseases involving tissue damage such as myocardial infarcation suggested that placental damage may also give rise to characteristic changes in maternal serum enzymes, which might be useful diagnostically. One of the problems in obstetrics is the recognition of placental 'dysfunction' or 'insufficiency', terms which are used by obstetricians to indicate a process of impaired transmission of nutrients resulting in retarded fetal growth, and progressing eventually to impaired oxygen transfer resulting in fetal hypoxia and possibly death from anoxia. The diagnosis depends on the demonstration of fetal distress during labour, or on the delivery of a baby with a low Apgar' score, or a birth weight below the 10th centile for that duration ofpregnancy. These criteria have only recently been applied to the evaluation of tests of placental function. It has been established that a number of enzymes in maternal serum remain unchanged in normal pregnancy, but that others increase either during normal or abnormal pregnancy or in both (Table I). Serum enzymes which do not change during normal pregnancy are cholinesterase (EC 3.1.1.8) (Meade and Rosalki, 1963; Rimbach and Figge, 1966), 2-hydroxybutyrate dehydrogenase (EC 1.1. 1.27) (Meade and Rosalki, 1963), and alanine and aspartate aminotransferases (EC 2.6.1.2.4.2.6.1.1) (Meade and Rosalki, 1963; Szekely and Fritzsh, 1969). Studies of lactate dehydrogenase (EC 1.1.1.27) and isocitrate dehydrogenase (EC 1.1.1.42) have given less uniform results. Whereas most authors have found them to remain unchanged, an increase in lactate dehydrogenase at term was found by Pulkkinen and Willman (1968) and a marked increase in isocitrate dehydrogenase was found at 39-40 weeks by Kraussold (1969). Serum 3-glucuronidase (EC 3.2.1.31), hyaluronidase (EC 3.2.1.35) and 3-acetylglucosaminidase (EC 3.2.1.30) have all been described as increasing late in normal pregnancy (Platt and Platt, 1968). 'The Apgar score is based on assessment of the baby's colour, heart rate, respirations, muscle tone, and the response to a catheter in the nostril. The best prognosis is indicated by a score of 10 and the worst by a score of 0. In abnormal pregnancy, many of the above enzymes have been found to increase. Thus increased levels of both aminotransferases were found in two out of 14 patients with mild pre-eclampsia, and 11 out of 12 with eclampsia (Dass and Bhagwani, 1964). These results were taken to mean that toxaemia is associated with liver damage, and it was suggested that estimations of serum aminotransferases might be of prognostic value in toxaemia. Similarly isocitrate dehydrogenase may show transient increases in pre-eclampsia or accidental haemorrhage (Jeacock, Morris, and Plester, 1962; Meade and Rosalki, 1963; Pulkkinen and Willman, 1968), possibly due to placental infarction (Dawkins and Wigglesworth, 1961). Pulkkinen and Willman (1968) also found increased levels ","PeriodicalId":75995,"journal":{"name":"Journal of clinical pathology. Supplement (Association of Clinical Pathologists)","volume":"4 ","pages":"90-5"},"PeriodicalIF":0.0,"publicationDate":"1970-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1136/jcp.s1-4.1.90","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16095207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enzyme assays in liver disease.","authors":"R J Wieme, L Demeulenaere","doi":"10.1136/jcp.s1-4.1.51","DOIUrl":"https://doi.org/10.1136/jcp.s1-4.1.51","url":null,"abstract":"It is in the field of hepatology that enzyme assays are performed most frequently for diagnostic purposes. Their interpretation requires knowledge of many factors that influence the serum level of the particular enzymes assayed. Therefore, these factors are discussed briefly in relation to liver disease before considering important developments such as the value of estimating D-glutamyltransferase (EC 2.3.2.1)' and the isoenzymes of alkaline phosphatase (EC 3.1.3.1). Finally, the application of these criteria to specific diagnostic problems is considered.","PeriodicalId":75995,"journal":{"name":"Journal of clinical pathology. Supplement (Association of Clinical Pathologists)","volume":"4 ","pages":"51-9"},"PeriodicalIF":0.0,"publicationDate":"1970-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1136/jcp.s1-4.1.51","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15255086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enzyme assays in diseases of the heart and skeletal muscle.","authors":"S B Rosalki","doi":"10.1136/jcp.s1-4.1.60","DOIUrl":"https://doi.org/10.1136/jcp.s1-4.1.60","url":null,"abstract":"Heart tissue injury may release cardiac enzymes into the circulation and elevate serum enzyme levels (LaDue, Wroblewski, and Karmen, 1954). Many enzymes become raised, but three enzymesaspartate aminotransferase (EC 2.6.1.1), creatine kinase (EC 2.7.3.2), and lactate dehydrogenase (EC 1.1.1.27)-have proved of particular diagnostic value. In addition, determination of lactate dehydrogenase isoenzymes by electrophoresis or other methods may be helpful, as may be the combined estimation of alanine aminotransferase (EC 2.6.1.2) and aspartate aminotransferase.","PeriodicalId":75995,"journal":{"name":"Journal of clinical pathology. Supplement (Association of Clinical Pathologists)","volume":"4 ","pages":"60-70"},"PeriodicalIF":0.0,"publicationDate":"1970-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1136/jcp.s1-4.1.60","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16041270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Histochemical localization and assay of enzymes.","authors":"F W Rost","doi":"10.1136/jcp.s1-4.1.43","DOIUrl":"https://doi.org/10.1136/jcp.s1-4.1.43","url":null,"abstract":"Histochemistry is a combination of chemistry and histology, in which reactions are carried out on tissue sections or similar preparations and the results examined under a microscope, with the object of combining the advantages of chemical or bio-chemical specificity and histological localization.","PeriodicalId":75995,"journal":{"name":"Journal of clinical pathology. Supplement (Association of Clinical Pathologists)","volume":"4 ","pages":"43-50"},"PeriodicalIF":0.0,"publicationDate":"1970-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1136/jcp.s1-4.1.43","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16041269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enzyme assays in diseases of erythrocytes.","authors":"T A Prankerd","doi":"10.1136/jcp.s1-4.1.71","DOIUrl":"https://doi.org/10.1136/jcp.s1-4.1.71","url":null,"abstract":"The human red cell has been the source of a great deal of information in medical science. It has provided evidence of genetic variation in natural populations and of the molecular basis of diseases in the case of abnormal haemoglobin, and it has been a model for studying a number of inherited diseases including those peculiar to the cell itself. It is the latter which is dealt with here.","PeriodicalId":75995,"journal":{"name":"Journal of clinical pathology. Supplement (Association of Clinical Pathologists)","volume":"4 ","pages":"71-4"},"PeriodicalIF":0.0,"publicationDate":"1970-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1136/jcp.s1-4.1.71","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16043442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enzyme changes in malnutrition.","authors":"J C Waterlow","doi":"10.1136/jcp.s1-4.1.75","DOIUrl":"https://doi.org/10.1136/jcp.s1-4.1.75","url":null,"abstract":"Since this symposium is concerned with enzymes in medicine, I shall consider only the work that has been done in human malnutrition. It would be impossible to deal with the very large literature on enzyme changes in animals under different dietary conditions. I shall also confine myself to work which is related to protein and calorie deficiency because this is the field with which I am familiar, although since most of the B-complex vitamins act as cofactors for one or more enzymes of intermediary metabolism or of the respiratory chain, certain enzyme measurements may be of value in the diagnosis of vitamin deficiencies, eg, the measurement of red-cell transketolase (EC 2.2.1.1.) in thiamine deficiency and of glutathione reductase (EC 1.6.4.2.) in riboflavin deficiency. Studies on enzyme changes in human subjects with protein-calorie malnutrition have, broadly speaking, followed three paths, with different aims and different underlying assumptions. These may be summarized as follows: (1) the study of enzymes as 'protein markers' to give information about the functional state of protein metabolism in the body as a whole, or in one tissue or organ; (2) the search for increases in enzyme concentration in blood or urine as evidence of cell damage; (3) the study of enzyme changes in tissues, in order to identify the underlying biochemical lesion in any given state of malnutrition.","PeriodicalId":75995,"journal":{"name":"Journal of clinical pathology. Supplement (Association of Clinical Pathologists)","volume":"4 ","pages":"75-9"},"PeriodicalIF":0.0,"publicationDate":"1970-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1136/jcp.s1-4.1.75","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16095206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The nature of isoenzymes.","authors":"A L Latner","doi":"10.1136/jcp.s1-4.1.8","DOIUrl":"https://doi.org/10.1136/jcp.s1-4.1.8","url":null,"abstract":"Many enzymes are known to exist in multiple molecular forms; in fact, it is now believed to be the exception rather than the rule for an enzyme to exist in only one fornm (Kaplan, 1968). The term 'isoenzyme' has been applied to each of these forms and, for the time being, it has been decided to retain a broad definition of isoenzyme such as 'one of a series of different proteins with similar enzymatic activity'. It is likely that eventually it will be established that the multiple forms of enzymes are merely a special example of the structural variations that occur in proteins generally, of which haemoglobin is a well known example, but until more is known of the molecular structure of isoenzymes, it would be unwise to adopt too narrow a definition. Some authorities have limited the term to the multiple forms of an enzyme which are all present in one tissue or organ of an individual plant or animal or in a culture of a unicellular organism. This narrow definition would not embrace the multiple forms of alkaline phosphatase (EC 3.1.3.1) which are found in many different tissues, but which are nevertheless customarily referred to as isoenzymes. The broad definition above also includes such examples as cytoplasmic and mitochondrial malate dehydrogenase (EC 1.1.1.37) although these have been regarded as entirely separate enzymes, each with its own isoenzymes; however, hybrids of these two enzymes have been prepared in vitro (Chilson, Kitto, Pudles, and Kaplan, 1966). The mitochondrial and cytoplasmic forms of aspartate aminotransferase are also very different in their properties. As has already been indicated, however, such difficulties will undoubtedly be resolved when the molecular composition and structure of the various 'isoenzymes' has become known. It is now common knowledge that proteins are composed of one or more polypeptide chains and that their molecular structure can be subdivided, into primary, secondary, tertiary, and quaternary components. The primary is of course the aminoacid sequence, which is also the final arbiter of the eventual shape of the molecule. The secondary structure is the occurrence within the polypeptide chains of alpha helices, the rigid parts of the chain, and the looser bent sequences-largely, but by no means entirely-determined by the presence of proline. The tertiary component, or final shape of a polypeptide, is brought about by the three-dimensional bending of the secondary form by forces such as hydrogen bonding, internal interactions of hydrophobic groupings, electrostatic bonding, van de Waals interactions, disulphide bridges, and the like. In accordance with thermodynamic considerations, there is little doubt that the final form is that structure with minimal energy content. Most proteins contain more than one polypeptide and the combination of these makes up the quaternary component of structure. It is now accepted that each polypeptide is synthesized as a result of a message initiated in a cistron, often l","PeriodicalId":75995,"journal":{"name":"Journal of clinical pathology. Supplement (Association of Clinical Pathologists)","volume":"4 ","pages":"8-13"},"PeriodicalIF":0.0,"publicationDate":"1970-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1136/jcp.s1-4.1.8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16041273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}