Fetal weight estimation from lengths and volumes found by three-dimensional ultrasonic measurements

A custom-built computer system combined with a commercial real-time ultrasonic scanner was used to predict fetal weight. A special three-dimensional (3D) locating system provided 3D coordinates of fetal surface points imaged on multiple ultrasound scans. The 3D coordinates were used to develop length and volume variables that are not available with commercial instruments. Multiple regressions were used to compare these lengths and volumes with more conventional diameters and circumferences for their ability to predict fetal weight. Measurements were made on 41 live fetuses within 48 hours prior to delivery (weight range 1,985-4,734 g, mean weight 3,421 g). Combinations of 19 measured variables were analyzed against birth weight and the natural log of birth weight. The correlation between log birth weight and combinations including lengths from 3D measurements was R = .93, SE = 73 g/kg. When volumes from 3D measurements (which are much more difficult to obtain) were added, the correlation was R = .94, SE = 69 g/kg. These results suggest that lengths from 3D measurements have the potential to improve fetal weight prediction by 25-30 per cent over current methods, which have an approximate error of 100 g/kg. The relative lack of improvement with volumes from 3D measurements is probably the result of technical problems which may be overcome with further research.

Fetal weight estimation from ultrasonic three-dimensional head and trunk reconstructions: evaluation in vitro

The theoretical usefulness of volume as a predictor of fetal weight was assessed on 25 dead neonates with weight ranges between 364 and 3,650 gm. The correlation between volume, measured by water displacement, and weight was r = 0.999, with a standard error of 37 gm. A method is described for using volume, calculated from three-dimensional ultrasonic head and trunk reconstructions, to predict fetal weight. For the dead neonates, the correlation between measured weight and calculated head plus trunk volume was r = 0.985, with a standard error of 190 gm. The regression coefficient was 1.73, thus indicating that head and trunk volumes underestimate weight, as might be expected since limbs were not included. We conclude from this "ideal" situation that volume measurements will eventually provide the best estimates of fetal weight, and that three-dimensional head trunk reconstructions are reasonably accurate measures of overall volume.

Isolation of a guinea pig macrophage glycolipid with the properties of the putative migration inhibitory factor receptor

We have previously established that preincubation of guinea pig macrophages with crude preparations of macrophage glycolipids enhances their response to a mediator of cellular immunity, migration inhibitory factor. This biologically active moiety found in the extracted material was attributed to a single glycolipid component. This component was purified to homogeneity by phase partition, ion exchange, adsorption, and thin layer chromatography. It migrates in the ganglioside region on thin layer plates, contains sialic acid and sphingosine. There is no apparent identity with any of the common gangliosides possessing the gangliotetraose structure. Homogeneity was demonstrated by rechromatography in four additional solvent systems. These results are discussed in the context of their implications for a deeper understanding of the putative receptor function of this glycolipid.

Effects of human complement component 1 inactivator on neutrophil chemotaxis and chemotactic deactivation

This study was undertaken to ascertain the relationship between complement-derived chemotactic factors and complement component 1 inactivator (C1INA) enhancement of neutrophil chemotaxis. Studies were also designed to determine whether the C1s- reactive or binding site on C1INA was functional in altering chemotactic responsiveness of neutrophilic leukocyes. Chemotaxis was assessed by determining cell migration in micropore filters. C1INA was found to enhance the chemotactic response to zymosan-activated plasma, C5a, and N-formyl-L-methionyl-L-phenylalanine and to bring the response of chemotactically deactivated cells to normal. In contrast, C1INA inhibited the chemotactic response to trypsin and EAC4oxy2-activated C3. Complexes of C1INA and C1s- failed to mediate the usual C1INA-enhanced response. Artificially produced C5-deficient plasma, when treated with zymosan, failed to support chemotaxis or to produce chemotactic deactivation. C1INA was without effect when this activated plasma was used as a source of chemotactic factors. We conclude from these data that C1INA enhancement of neutrophil chemotaxis to activated plasma is associated with C5-derived chemotactic fragments. The effects of C1INA are apparently related to the C1s- reactive or binding site(s) on the C1INA molecule. We suggest that C1INA may play a homeostatic role in neutrophil chemotaxis.

Role of sialic acid in the macrophage glycolipid receptor for MIF

Acidic glycolipids from guinea pig macrophages enhance the response of macrophages to migration inhibitory factor (MIF), suggesting a role of glycolipid receptors for this lymphocyte mediator. Neuraminidase treatment of these glycolipids results in the loss of their biologic activity. This activity remains intact after incubation of the glycolipids with beta-galactosidase. In order to investigate whether sialic acid is essential for the macrophage's response to MIF, macrophages were incubated with neuraminidase. Neuraminidase treatment of peritoneal exudate cells results in the abrogation of macrophage responsiveness to MIF. Other exoglycosidases such as beta-galactosidase and beta-glucosidase had no effect upon the macrophage response. The effect of neuraminidase was found to be reversible within 18 hr. These experiments suggest that macrophage glycolipids containing sialic acid are components of the macrophage receptor for MIF.

Role of sialic acid in the macrophage glycolipid receptor for MIF

Acidic glycolipids from guinea pig macrophages enhance the response of macrophages to migration inhibitory factor (MIF), suggesting a role of glycolipid receptors for this lymphocyte mediator. Neuraminidase treatment of these glycolipids results in the loss of their biologic activity. This activity remains intact after incubation of the glycolipids with beta-galactosidase. In order to investigate whether sialic acid is essential for the macrophage's response to MIF, macrophages were incubated with neuraminidase. Neuraminidase treatment of peritoneal exudate cells results in the abrogation of macrophage responsiveness to MIF. Other exoglycosidases such as beta-galactosidase and beta-glucosidase had no effect upon the macrophage response. The effect of neuraminidase was found to be reversible within 18 hr. These experiments suggest that macrophage glycolipids containing sialic acid are components of the macrophage receptor for MIF.