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F Klink

Publications and source records attributed to F Klink.

At least 37 records · Page 2Linked to original sources

[Blood coagulation and fibrinolytic factor activities in the amniotic fluid].

Plasma and 138 samples of amniotic fluid were obtained from 129 patients during the 15th to 39th pregnancy week and during parturition. Factor activities of the coagulation and fibrinolytic system were studied by means of enzymatic-kinetic measurement methods to differentiate the haemostaseological properties of the amniotic fluid. The factor X activity drops in the amniotic fluid during the third trimester and during parturition. The activities of plasminogen, alpha 1-antitrypsin, alpha 2-antiplasmin, antithrombin III and alpha 2-macroglobulin in the amniotic fluid do not change significantly during gestation and parturition. None of these factors seems to show any difference between the activities in the maternal placenta and in the amniotic fluid. The most striking change in activity was seen with prothrombin. There is a marked increase between the second and third trimester. In the maternal plasma the activity is relatively constant within the standard range of non-pregnant women. Further studies will be necessary to find out whether the increase in prothrombin activity in the amniotic fluid correlates with the increased surfactant production in the fluid and may thus be of diagnostic importance.

Amniocentesis↗

[Puncture of the chorionic villi. Technic--experiences--risks].

Chorion villi biopsy is a recently introduced method for first trimester prenatal diagnosis. Based on 435 cases of chorionic villi biopsies, obtained during a 3 year period, we report our experiences with the technique of chorionic villi sampling, chromosomal analysis from trophoblast tissue and possibly associated complications, such as spontaneous abortions, vaginal bleeding, and chromosomal mosaicism. The rate of spontaneous abortions in our group of patients was 3%. This appears low, considering the high overall spontaneous abortion rate in early pregnancy of women over 35 years. The cytogenetic diagnosis is complicated by a high rate (2.8%) of chromosomal mosaicism, which were found to be not representative for the fetus, but required control amniocentesis. From our experiences with this method we conclude that chorion villi biopsy can be offered as a reliable alternative method to amniocentesis in the hands of an experienced team of obstetric surgeons and cytogenetists.

Abortion, Spontaneous↗

[Bacteriologic studies in premature rupture of fetal membranes and correlation with the clinical aspects of chorioamnionitis and the amnion infection syndrome].

One of the major complications following premature rupture of the membranes (PROM) is ascending infection. In this aspect the bacteria of the vaginal flora play a major part. Bacterial spectra of a group with PROM and another control group with punctual rupture of the membranes are comparatively analysed. This analysis is based on swabs taken from vagina and newborns. Data are interpreted in correlation to clinical picture of chorioamnionitis and amnion infection syndrome (AIS). Twelve newborns clinical suspected to have a neonatal infection are retrospectively judged. In the group with pregnant women with PROM potential pathological germs such as group B streptococci and E. coli are found more often, whereas physiological flora, specially Lactobacillus species, are clearly reduced. In newborns with AIS even germs can be detected, which so far have seemed to be more apathogenic, such as Gardnerella vaginalis. Bacteriological findings are discussed in connection with clinical parameters, specially group B streptococci are looked at more precisely. In newborns with AIS microbiological results are demonstrated including course of pregnancy and delivery. For the management of PROM alternatives are shown and advice for prophylaxis is given.

Bacteria↗

[Ivemark syndrome].

The Ivemark-Syndrome (Alienie Syndrome) is defined by the characteristic association of splenic aplasia, organsymmetry and other malformations especially of the cardiovascular system. More than 200 cases are reported. The incidence of Ivemark-Syndrome is very low. The aetiology is not yet clearly defined. As a main cause exogen factors between the 31st and 38th day of gestation are discussed, but a genetic cause has not been detected yet. Due to the unfavourable prognosis an intensive ultrasonographic screening is to be asked for.

Abnormalities, Multiple↗

Primary structure of elongation factor 2 around the site of ADP-ribosylation is highly conserved from archaebacteria to eukaryotes.

Elongation factor 2 (EF-2) from eukaryotes and archaebacteria can be ADP-ribosylated by diphtheria toxin (DT) [(1977) Annu. Rev. Biochem. 46, 69-94; (1980) Nature 287, 250-251]. The primary structure of the ADP-ribose accepting region in EFs from the archaebacteria Thermoplasma acidophilum Halobacterium cutirubrum and Methanococcus vannielli was determined in order to elucidate the degree of conservation compared with 4 previously established eukaryotic sequences [(1971) FEBS Lett. 103, 253-255]. Within a 9-residue sequence including the site of ADP-ribosylation 5 positions were found to be occupied by the same amino acid in all the archaebacterial and eukaryotic factors studied. There were more differences among the 3 archaebacterial sequences than among the 4 eukaryotic ones.

Adenosine Diphosphate Ribose↗

[Gynecologic and cytogenetic aspects of prenatal diagnosis in the 1st trimester of pregnancy].

The article reports on a new method in prenatal diagnosis during the first three months of pregnancy. The gynaecological as well as the cytogenetic aspects are discussed on the basis of 74 transcervical trophoblast aspirations. Two different experimental preliminary examination series were conducted. In the first study, the failure rate in respect of recovery of material was 12.5%, whereas in the second examination series all aspirations were successful. Thanks to these favourable results, transcervical trophoblast aspiration was adopted as the only method used in prenatal diagnosis. In cytogenetic processing, direct chromosome preparation was found to be rather costly and time-consuming, whereas the short-term culture of chorionic villi usually yielded more favourable results in respect of mitotic rate and quality of the metaphase plates. It must be considered a drawback of transcervical trophoblast aspiration that it is not possible to conduct alpha-foetoprotein determination or determination of acetylcholine esterase as part of prenatal neural tube diagnosis. However, this can be subsequently done-with suitable disposition--during the 16th week of pregnancy, or can be replaced by a determination of alpha-foetoprotein in the serum of pregnant women.

Abortion, Induced↗

Ribosome specificity of archaebacterial elongation factor 2. Studies with hybrid polyphenylalanine synthesis systems.

Polyphenylalanine synthesis with ribosomes and two separated, partially purified elongation factors (EF) was measured in cell-free systems from the archaebacteria Thermoplasma acidophilum and Methanococcus vannielii, in an eukaryotic system from rat liver and an eubacterial one with Escherichia coli ribosomes and factors from Thermus thermophilus. By substitution of heterologous EF-2 or EF-G, respectively, for the homologous factors, ribosome specificity was shown to be restricted to factors from the same kingdom. In contrast, EF-1 from T. thermophilus significantly cooperated with ribosomes from T. acidophilum.

Animals↗

Effect of smoking on cadmium and lead concentrations in human amniotic fluid.

The amniotic fluids of 155 pregnant women, non-smokers (n = 128) and smokers (n = 27), were investigated on their cadmium (Cd) and lead (Pb) concentrations. The mean +/- s range of Cd in the amniotic fluid of non-smokers amounted to 2.58 +/- 1.36 ng/l, that of smokers to 7.29 +/- 2.39 micrograms/l. Moreover, there was a correlation between the extent of daily cigarette consumption and Cd levels. With Pb, higher concentrations were found ranging between 23.98 +/- 9.41 ng/l for non-smokers and 21.53 +/- 7.16 micrograms/l for smokers. No correlations were seen between age, week of pregnancy, blood pressure, disorders of pregnancy and the amniotic Cd or Pb concentrations. Thus, the maternal and fetal risks of the higher Cd levels in the amniotic fluid of smoking women remain unanswered.

Amniotic Fluid↗

[Cadmium and lead concentrations in the amniotic fluid of pregnant smokers and non-smokers].

Many studies showed the unhealthy effect of smoking on the fetus. Several mechanisms for the unfavorable effect are discussed. In the last few years interest has been shown in the occurrence of heavy metals such as cadmium and lead in smoke. In animal experiments high doses of cadmium showed mutations, teratogenicity and low doses showed retardation of fetal growth. Amniotic fluid examinations of smoking and non-smoking pregnant women showed that there is no barrier to cadmium from the placenta. A direct correlation between cigarette smoking and cadmium concentration in the amniotic fluid was found. Cadmium was discussed as a reason for hypertension. But this was not verified in our study. There were no correlations between the cadmium and lead content of amniotic fluid and the gestational age, and disturbances of the pregnancy nor a correlation to the incidence of abortions. The lead concentration in the amniotic fluid of smokers and non-smokers showed no significant difference. This is attributed to the ubiquitous exposition to lead with increasing pollution of the environment. The relatively small additional amounts of lead in cigarettes do not increase the amount of lead in the amniotic fluid.

Abortion, Spontaneous↗

The transcutaneous PO2 measurement as an additional evaluation index to the physiological and pathological conditions under delivery.

Transcutaneous PO2 was continuously recorded from 17 newborns sub partu by normal deliveries and four cases with umbilical cord complications. These data were correlated with the corresponding fetal heart rate alterations and the maximum of contraction directly and 30 s thereafter. During the course of delivery three stages are differentiated: first stage of labor, full cervix dilatation, second stage of labor. The statistical evaluation succeeded in the X2-test (P less than 0.01). Deriving from this result the tcPO2 measurement is an additional aiding procedure beside the cardiotocographic control for subpartal supervision.

Female↗

Two elongation factors from the extremely halophilic archaebacterium Halobacterium cutirubrum. Assay systems and purification at high salt concentrations.

Two peptide chain elongation factors from Halobacterium cutirubrum were purified nearly to homogeneity. They were identified and characterized by three assay systems working at very high salt concentrations: poly(Phe) synthesis, GDP binding and ADP-ribosylation. The purification procedure consisted of Sepharose 4B chromatography with a decreasing ammonium sulfate gradient, gel filtration on Sephadex G-100 in the presence of (NH4)2SO4 and, for each of the two separated factors, an independent adsorption chromatography on hydroxyapatite. The factors were absolutely dependent on high salt concentrations for stability and activity. Both factors (I and II) complement each other to give fully active poly(Phe) synthesis, which is totally inhibited by puromycin and anisomycin. Factor I (Mr 51 000) is a major protein of the cell-free extract. It binds GDP, which can be displaced by GTP only to a small extent. The function of factor I in poly(Phe) synthesis is not impaired by high concentrations of kirromycin. The observed characteristics resemble partly those of prokaryotic EF-Tu and partly those of eukaryotic EF-1. Factor II (Mr 111 000) can be ADP-ribosylated by diphtheria toxin, and thus was identified as an EF-2-type elongation factor.

Guanosine Diphosphate↗

Alpha-fetoprotein and beta-human chorionic gonadotropin in amniotic fluid.

A series of data on amniotic fluid levels of alpha-fetoprotein (AFP) and beta-human chorionic gonadotropin (HCG) are presented. Both hormones were observed to decrease with advancing gestational age. The diagnostic importance of AFP levels is confirmed, and the very high levels of beta-HCG in twin gestations are documented. A statistically significant correlation between the concentration of both hormones is demonstrated.

Amniotic Fluid↗

Uterine contraction intervals and transcutaneous levels of fetal oxygen pressure.

Continuous intrauterine transcutaneous PO2 (tcPO2) measurement was performed in 30 deliveries. The various characteristics of labor (peak of contractions, duration, and contraction interval) were correlated with the tcPO2 integral. The best correlation was seen between the tcPO2 integral and that of the contraction intervals. As the data show significant correlations with the pattern of labor, continuous tcPO2 measurement is a reliable and sensitive method for recognizing PO2 alterations early, especially in high-risk deliveries.

Female↗

Archaebacterial elongation factor is ADP-ribosylated by diphtheria toxin.

Archaebacteria have been defined as a 'third primary kingdom' of cells in addition to the urkaryotes and the eubacteria. While the latter two correspond approximately to the conventional categories eukaryotes and prokaryotes respectively, the Archaebacteria have up to now comprised four groups of microorganisms: the methanogenic bacteria, the extremely halophilic bacteria and the two thermoacidophilic genera Sulfolobus and Thermoplasma. Based on ribosomal RNA sequence homologies and lipid composition, they apparently form a distinct group. Furthermore they possess or lack typical biochemical markers of both the eukaryotes and the prokaryotes, as well as having unique properties not found elsewhere. Altogether, this indicates that they are not closer to either one of the classical categories. One clear-cut difference between prokaryotes and eukaryotes is the diphtheria toxin reaction, which catalyses the covalent binding of adenosine diphosphate-ribose (ADPR) to the eukaryotic peptide elongation factor EF2 in contrast to the homologous prokaryotic factor EF-G. We report here that diphtheria toxin also catalyses the ADP-riboslation of archaebacterial elongation factors. In this respect, these factors have to be assigned to the EF2 type; we suppose that the ADP-ribosylatable structure arising so early in evolution is of fundamental importance for the elongation process.

Adenosine Diphosphate Ribose↗