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H Lilja

Publications and source records attributed to H Lilja.

At least 163 records · Page 9Linked to original sources

The predominant protein in human seminal coagulate.

The predominant protein in human seminal vesicle secretion constitutes the structural protein of coagulated semen. This high molecular weight protein (HMW-SV-protein) is stable in seminal vesicle secretion during in vitro storage at 37 degrees C for at least 20 h, but is rapidly cleaved on mixing with prostatic proteases. Seminal coagulate, washed free of soluble components, is dissoluble by 2 to 3 mol/l of guanidine-HCl. Although dithiothreitol added to seminal coagulate does not liquefy the clot, complexes between HMW-SV-proteins are broken up by reduction under denaturing conditions, which suggests that the non-covalent linkages of HMW-SV-proteins are essential in the clot. Prostatic proteases cleave the HMW-SV-protein during liquefaction of ejaculated semen to a series of labile proteins. These proteins are further cleaved to peptides of successively decreasing size after completed liquefaction. The cleavage of the HMW-SV-protein is the major cause of the fast shift of the electrophoretic pattern of seminal proteins if semen is stored without protease inhibitors.

Amino Acids↗

Heart rate variability and electrocardiogram changes in the fetal lamb during hypoxia and beta-adrenoceptor stimulation.

Hypoxic changes in the ST waveform of the fetal electrocardiogram (FECG), with elevated T waves as the main response, have earlier been described in the fetal lamb as mediated via the beta-adrenoceptor cells, initiated by catecholamine release. A similar background to the increase in fetal heart rate variability (FHRV) during hypoxemia has been suggested. The aim of the present study was to elucidate this question and also to compare FHRV and changes in the ST waveform of the FECG as indicators of fetal distress. Twenty-six acutely exteriorized mature lamb fetuses were submitted to periods of graded hypoxemia. Fetal blood gases were measured and oxygen content was calculated. The FHRV was analyzed by a computer program and calculated as the differential index (DI) and the interval index (II). Eighty seconds of the recorded ECG coinciding in time with each fetal blood sample were analyzed using a PDP 11/40 minicomputer. The ECG signal was sampled at a rate of 1250 samples per second giving a resolution in time of 0.8 msec. Each QRS complex was detected with a semi-automatic program using a cross-correlation algorithm. QRS complexes that by the program were signalled to be doubtful were visually examined and either rejected or approved. Hence, the resulting list of R-R intervals was practically free from artefacts. From this list of R-R intervals the DI and II were computed according to YEH et al. [30]. Hypoxemia resulted in initially strongly increased DI from 3.1 +/- 2.5 to 17.7 +/- 13.8 (p less than 0.001) and in II from 1.88 +/- 0.65 to 3.77 +/- 2.06 (p less than 0.001) (Fig. 1). Obviously the change in oxygen content per se was strongly associated with the variability indices, as we found a strong correlation between delta oxygen content/min and delta DI/min (r = 0.81). In five fetuses the effect of prolonged hypoxemia on DI was studied (Fig. 2). After the initial rise from 1.6 +/- 1.1 to 31.2 /+- 9.0 (p less than 0.02) DI decreased to 19.4 +/- 20.7. A regression analysis showed a strong connection between DI and PaO2, (n = 93, T = - 5.34), whether there was no relation between DI and pH (T = - 1.85). There is strong evidence that hypoxemia and asphyxia induce an increase in the concentration of catecholamines in fetal blood [2, 23].(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

Treatment of intrauterine supraventricular tachycardia with digoxin and verapamil.

Intrauterine fetal supraventricular tachycardia (ISVT) is a rare condition which is connected with organic heart disease in only 4-10 per cent. However, neonatally these children develop heart failure in a high frequency (62 per cent). Intrauterine digitalization has been suggested as treatment, especially if the fetus is preterm. Fetal therapeutic concentrations might demand doses inconvenient to the mother. We hereby report one case of intrauterine SVT in the 26th gestational week treated with a standard dose of digoxin resulting in subtherapeutic umbilical digoxin levels. When no consistent influence on fetal heart rate could be seen, verapamil (80 mg x 3) was added to the treatment. A reversion of the tachycardia and the fetal ECG changes was achieved within two days. The verapamil treatment could be withdrawn after ten days, while the digoxin treatment was continued. An initial discrete heart enlargement also was reversed by the treatment. The delivery in gestational week 38 was uneventful and the child did well. A neonatal ECG showed a sinus rythm interfoliated with supraventricular extrasystoles. No signs of organic heart disease have appeared. When last seen at nine months of age, the ECG was normal and digoxin had been discontinued without recurrence of tachycardia.

Adult↗

Synthetic protease inhibitors and post-ejaculatory degradation of human semen proteins.

Normal post-ejaculatory proteolytic changes in human seminal plasma rapidly distort its electrophoretic protein pattern. This invalidates the electrophoretic evaluation of the content in the secretion from the accessory sex glands. Both agarose and sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE) were used to study the proteolytic changes and how they could be modified by various synthetic protease inhibitors. Liquefaction of coagulated semen could be inhibited by adding o-phenanthroline directly after ejaculation, whereas neither neutrally buffered Na2EDTA, di-isopropylfluorophosphate (DFP), benzamidine, nor thiol reagents proved effective. Addition of the serine protease inhibitors DFP and benzamidine, o-phenanthroline, and iodoacetamide substantially retarded the proteolytic alterations of the proteins as demonstrated by both agarose electrophoresis and SDS-PAGE. We recommend that electrophoretic protein analysis of human semen be performed on ejaculates collected in vessels containing protease inhibitors. For routine analysis, the addition of benzamidine ensures sufficient stable proteins to permit reliable electrophoretic analysis of samples stored at room temperature for 4 h.

Chelating Agents↗

Characterization of the predominant basic protein in human seminal plasma, one cleavage product of the major seminal vesicle protein.

From liquefied human seminal plasma, we purified the predominant basic protein which appears following liquefaction of coagulated semen. The protein was purified in the presence of di-isopropylfluorophosphate to retard its degradation. Heparin-Sepharose chromatography was followed by gel filtration (Biogel P 60) and by fast performance liquid chromatography on a reversed phase column (C8). The basic protein is a single polypeptide chain with an apparent molecular mass of 12.8 kDa, and has a pI value between that of trypsinogen (9.3) and cytochrome C (10.3). The protein contains no carbohydrate, is rich in histidine, glutamate, and lysine, but is devoid of both cysteine and methionine. The amino-terminal portion of the protein sequence is unique: H N K Q E G R D H D K S K G H F H R V V I H H K G G K A H R G-. A specific rabbit antiserum was raised against the 12.8 kDa basic protein. The protein was found to be unique to seminal plasma among all extracellular fluids examined. Three immunologically related 52 kDa, 71 kDa, and 76 kDa proteins were identified in seminal vesicle secretion when it had been reduced. Prostatic enzyme(s) degraded these proteins to the 12.8 kDa basic protein and several other basic proteins with apparent molecular masses below 18 kDa.

Amino Acid Sequence↗

Liquefaction of coagulated human semen.

Liquefaction of coagulated human semen was inhibited by o-phenanthroline; subsequent addition of Zn2+ reversed this inhibition, but not if the coagulum was repeatedly washed before Zn2+ was added. No liquefaction of the coagulum occurred when Fe2+ was added (in a 1:3 molar ratio to o-phenanthroline), and the gel repeatedly washed. This o-phenanthroline-depleted coagulum was liquefied by resuspended pellet from ultracentrifuged pooled seminal plasma. In denatured and reduced semen coagulate, we identified the 52 kDa, 71 kDa, and 76 kDa protein bands of the predominant seminal vesicle protein. The protein was not present in the supernatant after centrifugation of coagulated semen, and it was degraded to several minor basic proteins when semen liquefied. These findings imply that the predominant seminal vesicle protein functions as the structural protein of coagulated semen. In much the same way as in ejaculated semen, the 52 kDa, 71 kDa, and 76 kDa protein bands in seminal vesicle secretion collected postmortem were digested to minor basic proteins after incubating the secretion with resuspended pellet from ultracentrifuged seminal plasma. This pellet contained the membrane-bound succinyl(alanine)3-p-nitroanilide hydrolysing peptidase of prostatic origin which, like the liquefaction process, was active in the presence of EGTA, inhibited by non-chelated Zn2+, and inactivated by o-phenanthroline--an inactivation that was reversed by Zn2+.

Electrophoresis, Polyacrylamide Gel↗

Phosphorus-31 NMR studies of smooth muscle from guinea-pig taenia coli.

Phosphorus-31 NMR spectra of superfused isometrically mounted guinea-pig taenia coli were obtained using a horizontal probe at 103.2 MHz. The spectra showed resonances for ATP, phosphocreatine (PCr), and a sugar phosphate resonance. The PCr/ATP ratio was between 1.5 and 2.0 consistent with chemical analysis of tissue extracts. The level of PCr, but not of ATP, decreases reversibly during contraction or inhibition of respiration. These conditions did not cause substantial changes in the intracellular pH, which was 7.0 +/- 0.1.

Adenosine Triphosphate↗

Evaluation of serum gamma-glutamyltransferase by electrofocusing, and variations in isoform patterns.

Serum gamma-glutamyltransferase (EC 2.3.2.2) showed microheterogeneity on electrofocusing, owing to variations in sialic acid content. We investigated the isoform patterns of papain-treated serum samples on agarose gels containing nonionic detergent and ampholytes in the low pH range. Serum from cases of cholestasis show seven bands with gamma-glutamyltransferase activity. These same bands were also found in liver tissue similarly treated, and they had pl values ranging from 3.8 to 4.2. Papain-treated sera that also had been neuraminidase digested showed only a single band, still enzymatically active and with a pl of 5.9. Increased gamma-glutamyltransferase in serum as a result of alcohol abuse was combined with a abnormally high degree of sialylation of the enzyme, giving more anodal isoforms. The decline in the concentration of this enzyme during several weeks of abstinence was accompanied by a gradual decrease in gamma-glutamyltransferase sialyation and the appearance of more cathodal fractions.

Adult↗

gamma-Glutamyltransferase bound to prostatic subcellular organelles and in free form in human seminal plasma.

Most of the gamma-glutamyltransferase occurring in semen was found to be bound to the membranes of prostatic organelles, as is the case with Mg++-Ca++-dependent ATPase, and Zn++-dependent peptidase hydrolysing succinyl (alanine)3-paranitroanilide. Organelle-bound gamma-glutamyltransferase was released in a water-soluble form by papain. Charge shift electrophoresis revealed the presence in seminal fluid of a small additional amount of gamma-glutamyltransferase that is unbound and water-soluble, but also of prostatic origin. After papain treatment there was no sign of the organelle-bound Zn++-dependent peptidase activity, nor of the Mg++-Ca++ dependent ATPase activity, both having been inactivated by the papain. Both organelle-bound gamma-glutamyltransferase and Zn++-dependent peptidase could be rendered soluble in active form with the non-ionic detergent Triton X-100.

Centrifugation, Density Gradient↗

Changes in the ST waveform of the fetal lamb electrocardiogram with hypoxemia.

The ST waveform of the fetal electrocardiogram (ECG) was examined in 10 chronically instrumented fetal lambs from 115 days to term. Averaged ST waveforms were plotted at 5-minute intervals in six fetuses for 2 to 22 days. No diurnal or other rhythms were seen. To correct for changes in signal gain the amplitude of the T wave was measured relative to the amplitude of the QRS complex. The T/QRS ratio was normally less than 0.30. Persistently elevated ST waveforms with a T/QRS range 0.32 to 0.65 preceded fetal death by some days in three fetuses and were associated with anemia and/or hypotension in a further three. In these animals hypoxia produced a further rise in the ST waveform (mean T/QRS, from 0.48 to 0.81) and all died during labor. In lambs with a normal ST waveform there were differences in the response to hypoxia over 1 hour for a similar fall in PO2. In eight experiments the ST segment and T wave increased (mean T/QRS, from 0.17 to 0.59) and promptly reverted to normal with normoxia. There was a significant rise in mean arterial blood pressure, plasma lactate, and glucose and a fall in pH. In four experiments there was little change (mean T/QRS, from 0.19 to 0.25), with a small rise in plasma lactate suggesting that these lambs were able to maintain aerobic myocardial metabolism. Overall there was a strong correlation of the T/QRS ratio to the rate of rise of lactate. These findings complement previous results in the acute fetal lamb preparation and suggest that ST waveform elevation expressed as the T/QRS ratio identifies a change to anerobic myocardial metabolism.

Animals↗

Neonatal electrocardiographic changes in relation to cardiotocographic changes.

Electrocardiograms (ECG) were made immediately after delivery in 28 infants with normal cardiotocographic patterns in labour and in 29 with abnormal patterns. Changes in the S-T segment and T-wave were quantified in a scoring system. High and peaked T-waves (high T/QRS-ratios) were significantly more common in the group with abnormal cardiotocographic patterns. The infants with ECG-changes also had significantly lower Apgar scores and more neonatal complications. The immediate postpartum ECG seems to be a useful indication of the accumulated hypoxic stress to which the child has been subjected in labour.

Apgar Score↗

Pt(CN)2-4 and Au(CN)-2: potential general probes for anion-binding sites of proteins. 35Cl and 81Br nuclear-magnetic-resonance studies.

Nuclear magnetic quadrupole relaxation appears to be a general method for studying the binding of anions to proteins. This is shown by the increase in transverse quadrupole relaxation rate of 35Cl- and 81Br- in the presence of horse liver alcohol dehydrogenase, lysozyme, trypsin, alpha-chymotrypsin, human carbonic anhydrase, fructose-1,6-bisphosphate aldolase and human serum albumin. Of the many possible binding sites at the surface of a protein (e.g. positively charged amino acid side-chains) only a few account for the main part of the relaxation enhancement. This is shown by the decrease in 35Cl- and 81Br- relaxation rate on addition of functional ligands. Large, kinetically inert, complex anions like Pt(CN)2-4 and Au(CN)-2 are found to act as strong competitors towards halogen ions for the high-affinity anion binding sites of a number of proteins. Titrations with complex anions following the 35Cl- or 81Br- relaxation rates are found to be helpful in attempts to elucidate binding mechanisms. Especially, the complex anions may be useful probes for the discrimination between general and metallic anion binding sites in proteins and they also permit correlation of information from X-ray investigations of crystals with that from physical measurements in solution. From the change in halide ion quadrupole relaxation rate on addition of strongly binding ligands the quadrupole coupling constants of the high affinity Cl- and Br- binding sites are estimated using certain assumptions. It is found that for several proteins, comprising the metal-free proteins but also alcohol dehydrogenase and Escherichia coli alkaline phosphatase, the 35Cl quadrupole coupling constants have approximately the same values. For some other metallo-proteins like carbonic anhydrase and a zinc - serum-albumin complex considerably greater quadrupole coupling constants were obtained. The estimated quadrupole coupling constants are used as a basis for a discussion of the interactions involved in anion-protein interactions.

Anions↗

19-F NMR studies of the binding of a fluorine-labeled phosphonate ion to E. coli alkaline phosphatase.

The interaction of a fluorinated phosphonate with Zn-2+-and Mn-2+-alkaline phosphatase as studied by 19-F NMR revealed a stoichiometry of 1:1 for the binding of the phosphonate anion to the enzyme. In the presence of two metal ions, one fluorinated phosphonate ion was found to interact strongly with the enzyme, while a different interaction was observed when the number of metal ions per enzyme exceeded two. Phosphate replaced enzyme bound phosphonate, as is shown by the 19-F NMR spectra. No direct interaction between the fluorinated phosphonate and the metal ion responsible for enzyme activity was indicated by the 19-F NMR data. This observation supports the idea of a considerable distance between metal ion and substrate binding site in Escherichia coli alkaline phosphatase.

Alkaline Phosphatase↗

Time-resolved fluorometry in end-point and real-time PCR quantification of nucleic acids.

Two time-resolved fluorescence-based methods for nucleic acid quantification are described and their results are compared. Both methods use an exogenous internal standard to eliminate errors arising from different steps of the assay. The first method is a competitive end-point assay, where the standard competes for the same primers with the actual target sequence, prostate-specific antigen (PSA) cDNA. The standard and target are quantified in a dual-label plate hybridization with lanthanide-labelled probes after a fixed number of PCR cycles. The second method is based on real-time monitoring of PCR and on the use of a novel homogeneous signal generation principle that relies on the use of a 5'-->3' exonucleolytic DNA polymerase and a probe labelled with an environment sensitive, stable and fluorescent lanthanide chelate. In this assay, a non-competitive, exogenous internal standard is used. Both assays have a wide linear range (50-5 x 10(6) and 10-5 x 10(7) input PSA cDNA molecules for the end-point and real-time assays, respectively) and there is a strong correlation between the results obtained with the two assays (r = 1.0). Being somewhat faster to perform, the real-time format is better suited for assays that require high throughput.

Base Sequence↗

Time-resolved fluorescence imaging for quantitative histochemistry using lanthanide chelates in nanoparticles and conjugated to monoclonal antibodies.

Tissue and cell examinations have a potential to produce extremely valuable information about antigen quantities in samples. Using currently available methods, a truly quantitative analysis is nearly impossible. We have previously shown that immunohistochemical (IHC) detection of prostate-specific antigen and human glandular kallikrein from prostatic tissue, together with time-resolved fluorescence imaging (TRFI), is a suitable method for obtaining quantitative data from biological samples and that the signal response is linear. In this paper we show that Eu-chelate containing particles in the nanometer range are suitable labels for quantitative IHC. Even single nanoparticle molecules can be detected by TRFI and the signals measured can be readily quantitated. The signal intensity correlates very well with the amount of bound label, and the use of nanoparticles could markedly improve the sensitivity of quantitative IHC methods. TRFI provides a powerful tool for providing quantitative data about antigens or transcripts in tissue sections or cultured cells. It is also of major importance in standardization and optimization of protocols for fixation and tissue preparation, including antigen retrieval methods.

Animals↗