Monitoring the fetal heart non-invasively: a review of methods.

Doppler ultrasound, ultrasound M-mode analysis, fetal electrocardiography, and fetal magnetocardiography are methods by which the fetal heart can be monitored non-invasively. In this paper, they are evaluated and compared. Customarily, it is solely the fetal heart rate, which is monitored using the Doppler ultrasound technique since it is both simple to use and cheap. However, this method inherently produces an averaged heart rate and therefore cannot give the beat-to-beat variability. Fetal electrocardiography has similar advantages, but in addition offers the potential for monitoring beat-to-beat variability and performing electrocardiogram morphological analysis. Its disadvantage is that its reliability is only 60%, although it is the only technique that offers truly long-term ambulatory monitoring. Ultrasound M-mode analysis allows a estimation of atrial and ventricular coordination, as well as an estimation of PR intervals. Bradycardias, supraventricular tachycardias, extra systoles are readily diagnosed using this method although timing will be inaccurate. Fetal magnetocardiograms can be detected reliably and used for accurate beat-to-beat measurements and morphological analysis. Consequently, they can be used for the classification of arrhythmias and the diagnosis of a long QT syndrome and some congenital heart diseases.

Compact long-term recorder for the transabdominal foetal and maternal electrocardiogram.

Foetal heart rate (FHR) monitoring is a proven means of assessing foetal health during the antenatal period. Currently, the only widely available instrumentation for producing these data is based on Doppler ultrasound, a technology that is unsuitable for long-term use. For nearly a century, it has been known that the foetal electrocardiogram (FECG) can be detected using electrodes placed on the maternal abdomen. Although these signals suggest an alternative means of FHR derivation, their use has been limited owing to problems of poor signal-to-noise ratio. However, the eminent suitability of the transabdominal FECG for long-term FHR monitoring has suggested that perseverance with the technique would be worthwhile. The paper describes the design, construction and use of a compact, long-term recorder of three channels of 24 h antenatal transabdominal data. Preliminary use of the recorder in around 400 short recording sessions demonstrates that FHR records of equivalent quality to those from Doppler ultrasound-based instruments can be extracted from such data. The success of FHR derivation is, on average, around 65% of the recording period from around 20 weeks gestation (although this figure is reduced from around 28-32 weeks, and the success rates exhibit a wide range when individual subjects are considered). These results demonstrate that the technique offers, not only a means of acquiring long-term FHR data that are problematic to obtain by other means, but also a more patient-friendly alternative to the Doppler ultrasound technique.

Factor structure of neurologic examination abnormalities in unmedicated schizophrenia.

The heterogeneity and uncertain significance of neurologic exam abnormalities in schizophrenia prompted us to evaluate their factor structure. We administered a modified version of the Neurological Evaluation Scale (NES) to 103 unmedicated patients with schizophrenia. Data were distilled by combining right- and left-side scores, and by eliminating superfluous, rarely abnormal and unreliable items from the analysis. Exploratory principal components analysis yielded four factors: repetitive motor tasks (fist-ring, fist-edge-palm, alternating fist-palm, dysdiadochokinesis); cognitive-perceptual tasks (memory, audiovisual integration, right-left orientation, face-hand test, rhythm tapping reproduction); balancing tasks (Romberg, tandem gait); and the palmomental reflex. Evaluation of the relationship between these factors and clinical and demographic variables revealed a robust correlation between the cognitive-perceptual factor and full-scale IQ score. This analysis is a step toward developing empirical subscales of a modified NES, which may provide insights into the nature of neurologic impairment in schizophrenia and may prove clinically useful.

Supramolecular receptor structures in the plasma membrane of lymphocytes revealed by flow cytometric energy transfer, scanning force- and transmission electron-microscopic analyses.

Receptors in the plasma membrane of blood cells in general and in that of lymphocytes in particular are supposed to move around in a random walk fashion relatively freely driven by thermal diffusion, as described by the Singer-Nicolson fluid mosaic membrane model. In this article we summarized data and techniques that indicated nonrandom codistribution patterns of receptor superstructures under conditions, where the generation of such molecular colocalizations by the methods themselves were excluded. Application of fluorescence energy transfer in a flow cytometer helped to analyze such codistribution patterns in cell populations. After normalizing energy transfer values for possible differences between labeling ratios of the targeting monoclonal antibodies and using the mean values of energy transfer distribution curves, two-dimensional receptor maps were generated from data obtained in a pair-wise fashion between receptors. Major histocompatibility complex (MHC) class I and II, intercellular adhesion molecule-1 (ICAM-1), TcR-CD3-CD4, tetraspan molecules (CD81, CD82, CD53), and the subunits of the multisubunit IL-2 receptor displayed nonrandom codistribution patterns sometimes with, but very frequently without induction by their ligand. Immunogold-bead "sandwich" labeling analyzed by atomic force microscopy has shown that such receptor "islands" existed also in "receptor-island-groups". This indicated the existence of nonrandom receptor distribution of MHC class I and II molecules also at an elevated hierarchical level. An analysis is given herein concerning a standardized approach. The apparent incompatibility of these supramolecular patterns with the Singer-Nicolson type "free-protein and lipid-mobility paradigm" was resolved by recommending an additional emphasis on the mosaicism of the membrane besides receptor mobility.

Identification of 137Cs-and 241Am-binding sites in the oyster Crassostrea gigas.

The subcellular distribution and binding of 241Am and 137Cs in the visceral mass of the oyster Crassostrea gigas were investigated following exposure to sea water contaminated with these radionuclides. 241Am was predominantly sequestered by the lysosomal system. Approximately, 10% of 241Am was associated with soluble macromolecules. 241Am was bound to lipofuscin, ferritin and to unidentified ligands of 60 to 15 kdaltons mol. wt. No evidence was found for binding of 241Am to metallothionein synthesized de novo. In contrast, only small amounts of 137Cs were present in lysosomes and 137Cs was not associated with soluble cellular proteins. These results indicate that they enter complete separate metabolic pathways.

Binding of 241Am to carp cytosolic fractions in vitro.

Recent studies on the competition between Cd and radionuclides have been reported in marine species. The present investigation aims to study the binding of 241Am to freshwater fish cytosolic fraction before and after Cd-treatment. The main organs studied are the liver, kidneys and muscles. The distribution of americium in the liver cytosol of carp cadmium treated shows a preferential fixation on a 10 KDa fraction with high sulfhydril compounds.

Biodynamic study of americium-241 accumulation in the cytosol of the hepatopancreas of the lobster Homarus gammarus.

In the lobster, most of the radionuclides ingested with contaminated food are concentrated in the digestive gland. Americium-241 accumulation in the hepatopancreas of the lobster was studied during the digestive cycle. Fractionations of cytosols at different times after ingestion of radioactive preys were performed by gel permeation chromatography to determine the distribution of 241Am in the different macromolecular components. 241Am was associated with ferritin during the whole digestive cycle. This observation suggests a correlation between 241Am distribution pathways and iron metabolism. The distribution of 241Am present in the other cytosolic proteins followed two major steps of accumulation which may be correlated to the evolution of the two main cellular types playing an important role in the digestive cycle (B and R type cells).

Chemical behaviour of three radionuclides (cesium, americium and technetium) and their uptake at the cytosolic level in aquatic organisms.

In previous papers, we observed that there were great differences in the subcellular accumulation and elimination of 137Cs, 99Tc and 241Am in different marine animals. In this study, we analysed and compared the behaviour of these radionuclides at the cytosolic level. We found great similarities in the cytosolic distribution of a given radionuclide in the various organisms studied. The chemical characteristics of the radionuclides seem to play a major role in the biochemical affinity and metabolic behaviour in different aquatic organisms.

Distribution of [241Am] in hepato-pancreatic nuclear proteins of the lobster (Homarus gammarus).

Recent studies on the bio-accumulation of transuranic elements in marine invertebrates have demonstrated an intracellular concentration of radionuclides in the digestive gland. The present investigation aims to establish the distribution of [241Am] within the different structures of the cell nucleus. Lobsters were experimentally contaminated through feeding and then killed. The nuclei of hepato-pancreatic cells were isolated, purified and dissociated. The different protein categories were separated in media of increasing ionic strength. The distribution of americium in this material yielded results showing a preferential fixation onto the structural proteins of the nuclear matrix. The radiological consequences of such an affinity are discussed in terms of the life-times of the ligands concerned.

Conditions for the extraction of protease-free LMG proteins from calf thymus.

Calf thymus LMG proteins are known to be susceptible to a wide variety of chromatin-associated proteases. We have investigated the use of different inhibitors to protect LMG chromosomal proteins from proteolytic degradation. In this work we have developed a preparative method for the extraction of LMG proteins from purified chromatin which provides an LMG protein extract devoid of proteolytic activity.

Determination of alpha-tocopherol in plasma, platelets and erythrocytes of type I and type II diabetic patients by high-performance liquid chromatography.

Vitamin E (alpha-tocopherol) concentrations of plasma, platelets and erythrocytes were determined by HPLC in insulin-dependent (type I) and age-matched non-insulin-dependent (type II) diabetic patients and in two control groups. Plasma alpha-tocopherol levels were significantly increased in diabetic patients compared to control groups. Platelet and erythrocyte alpha-tocopherol levels were not significantly different in type I and type II diabetics as compared to their respective control groups, but differed from one another. Plasma vitamin E concentrations showed a significant correlation with plasma cholesterol and apoprotein B concentrations in different groups. The alpha-tocopherol/cholesterol and alpha-tocopherol/apoprotein B ratios in plasma were higher in diabetic patients, as were triglyceride contents. Platelet vitamin E levels were not significantly correlated with plasma concentrations. These findings suggest that vitamin E activity is altered in diabetic patients but that no diet supplementation seems necessary.

Low mobility group (LMG) non histone chromatin proteins: fractionation and characterization by high performance liquid chromatography.

Low mobility group nuclear proteins extracted from the 0.35 M NaCl non histone proteins of calf thymus chromatin were fractionated by preparative high performance liquid chromatography. The different fractions were characterized by polyacrylamide gel electrophoresis and amino acid analysis.

[Demonstration of non-histone nuclear proteins in mouse myeloma. Trial comparative study]. / Mise en évidence des protéines nucléaires non histones d'un myélome de Souris. Essai d'étude comparative.

The non-histone chromosomal proteins from mouse myeloma cell line X 63-Ag 8.653 have been studied using two dimensional polyacrylamide gel electrophoresis. Our results were compared to previous analysis of other myeloma cell lines.

[Comparative study of lymphocyte non-histone proteins]. / Etude comparative de protéines non-histones lymphocytaires.

The non-histone chromosomal proteins of bovine lymphocytes were investigated by the two dimensional gel electrophoresis of O'Farrell. The 0.35 M NaCl extractable proteins from lymphocyte nuclei, the high mobility group proteins (HMG) and some proteins released from nuclei by DNase I were compared on the basis of their electrophoretic patterns.

[Study of a non-collagen protein fraction of dentin during minerlization]. / Etude d'une fraction protéique non collagénique de la dentine en voie de minéralisation

A protein fraction of mineralizing porcine dentine was analysed after E.D.T.A. demineralization. This fraction of heterogeneous composition had a high content of phosphorus. Its acid character, deductible from the amino acid analysis, was confirmed by electrophoresis. After Sephadex gel filtration, five fractions were obtained. They could be characterized by amino acid analysis and phosphorus dosage. Two fractions contained phosphorus and were very rich in aspartic acid and serine. The three other fractions were characterized by their very high content of glycine.