Quantitative determination of lysozyme in the blood serum]

A method, based on the lysozyme ability to selective sorption on chitin followed by reversible enzyme-substrate complex formation, is suggested for quantitative determination of lysozyme in blood serum. The technique offers no difficulty in application, requires no expensive equipment and therefore can be used in clinical practice.     

Comparative studies on the determination of the A-hel blood group factor in the pig by use of various lectins]

Comparable investigations of the A-hel-receptor with Anti-AHP and 6 different phytagglutinins are reported which have been tested in 305 samples of pig blood. Anti-ADb disposing of a higher specificity is recommended for determining the Hel-factor in pigs instead of Anti-AHP.     

On the possibility of the MN blood group determination in human bones

After a series of preliminary tests on inert substances and on saliva drawn from donors of know MN blood group, 31 right femura from Pisa cemetery buried for 25–30 years and 37 eneolithic femura from Gaudo necropolis near Paestum (2500 – 2000 B.C.) were submitted to 140 assays for the MN system using the standard technique already devised in our Laboratory for ABO blood group determination.Positive and reproducible results were obtained in 18:31 recent femura (58%) and in 24:37 eneolithic bones (65%). The following phenotype and gene frequencies were obtained:

$\text{recent femura:}\text{8.}\text{M}\text{+3.}\text{N}\text{+7.}\text{MN}\text{=18; 0·64m+0.·36n=1}$

$\text{eneolithic femura:}\text{9.}\text{M}\text{+6.}\text{N}\text{+9.}\text{MN}\text{=24; 0·56m+0·44n=1}$

When the ABO and the MN blood group determinations are performed in parallel, a significant positive connection between the two diagnosabilities is observable: P = 0·0387 in the case of the eneolithic bones, $\text{P ? 0·02}$ in the case of the total sample of 59 eneolithic and recent bones tested in parallel. This fact could be reasonably explained considering the similarity of the chemical structure of MN and ABO glycoproteins, which would account for a similar behaviour in preservation.The absence or the very low concentration of M and N substances in tissues and body fluids would on the other hand agree with the percentage of diagnosability: lower in the MN system (60–65%) than in the ABO system (75–80%). The more problematical character of MN blood group typing of bones could be better approached if further research were done.     

The determination of the antibodies and the somatic O-antigen of Salmonella group B by using the complement-bound lysis of liposomes]

A simple and sensitive method for the determination of group B Salmonella O-antigen and specific antibodies to group B Salmonella by means of the complement-dependent lysis of liposomes sensitized with S. typhimurium lipopolysaccharide (LPS) is proposed. The factors affecting the sensitivity of the method during the determination of antibodies and free antigen have been studied. The method permits the determination of soluble LPS antigen in concentrations of 0.5-200 micrograms/ml.     

The biochemical aspects of blood group antigens]

The biochemical aspects of the immunodominant structures of blood groups antigens are mainly restricted to the following: ABH and Lewis in secretory fluids or on the red blood cells; P system (P1, P, Pk antigens); MN antigens and related; Tn and Tn antigens; Some hypothesis may be put forward for the I, i antigens. Many other antigens seem to be on the dependence of interactions between proteins and lipids of the red cell membrane; such immunodominant structures are not yet known. Except for the ABH and Lewis groups, the biosynthesis pathways are at present unclear.     

Conformational studies of blood group A and blood group B oligosaccharides using NMR residual dipolar couplings

The conformations of two synthetic trisaccharides of blood group A and B (alpha-L-Fucp-(1-->2)-[alpha-D-GalpNAc-(1-->3)]-alpha-D-Galp and alpha-L-Fucp-(1-->2)-[alpha-D-Galp-(1-->3)]-alpha-D-Galp, respectively) and of a type A tetrasaccharide alditol, Fucp-(1-->2)-[alpha-D-GalpNAc-(1-->3)]-beta-D-Galp-(1-->3)-GalNAc-ol, were studied by NMR measurements of one-bond C-H residual dipolar couplings in partially oriented liquid crystal solutions. The conformations of the three oligosaccharides were analyzed by generating thousands of structures using a Monte-Carlo method. Two different strategies were applied to calculate theoretical dipolar couplings for these structures. In the first method, the orientation of the molecule was calculated from the optimal fit of the molecular model to the experimental data, while in the second method the orientation tensor was calculated directly from the moment of inertia of the molecular model. Both methods of analysis give similar results but with slightly better agreement with experiment for the former one. The analysis of the results implies a single unique conformation for both blood group epitopes in solution in disagreement with theoretical models suggesting the existence of two conformers in solution.     

A-like specificity in Tn-activated erythrocytes of blood group B]

A Tn-polyagglutinability was observed in a 35 years old female patient with metrorrhagia. The A-like specificity of Tn-activated erythrocytes found simultaneously is especially significant, because this patient belonged to the blood group B, up till now, however, A-like findings have been described only for blood group O.     

Antigenic and blood group activity of lamb gastric mucoproteins]

The antigenic properties of a lamb mucin and of a glycoprotein isolated from it are investigated. The proteins are studied by immunoelectrophoresis of the mucin and of the glycoprotein against either a sheep serum antiserum or an exclusively glycoprotein antiserum. No serum protein could be shown in the mucin. In addition, the glycoprotein gives a precipitin line only with the specific antiserum; its antigenic power seems to be concealed in the original mucin. The carbohydrates are studied through the investigation of the blood group activities by the hemagglutination inhibition technique. The mucin and the isolated glycoprotein show the same types of activities: they both prevent the agglutination of A1 and 0 red cells. The presence of two blood group activities in that glycoportein and its non-reactivity against A2 red cells corroborate the hypothesis that carbohydrate chains must be branched for the elicitation of these activities in a single molecule.     

Hemolytic transfusion accident due to the blood group antibody anti-Jka]

A haemolytic transfusion incident caused by anti-Jka is reported about. In a 56 year old patient suffering from chronic iron deficiency anaemia an immunization in the Kidd system has taken place within 9 days. In the course of this immunization the fourth incompatible blood transfusion caused a severe transfusion incident. The necessity of serological compatibility testing by the indirect antiglobulin or enzyme test and the significance of making a strict indication for blood transfusions are referred to.     

Strategy of pretransfusion diagnosis in planned operations--experiences with the BAB (blood group determination, antibody determination test, blood availability) system

A report is presented on the first experiences gained after introducing a system for the reduction of pretransfusional diagnostics (BAB-system). By using this system at the University clinics of the Charité, Berlin, it was possible to lower the quotient of crossmatch/transfusion to 1.8 and to increase the availability of stored blood by 15%. So, the application of the BAB-system will lead to an increase of efficiency in compatibility tests prior to transfusion, thus contributing to an optimization in blood storage.     

Use of methods of derivative conductometry and photometry for assessing the structure of a cellular suspension]

Experimental proofs for the possibility of studying the dynamical structure of rotatory moving erythrocyte suspension with the methods of derivative conductometry and photometry are presented. The amplitude of the recorded impulses was proportional to the cell concentration and the angle velocity, and strongly depended on the shape of the suspended cells.     

Automatic noninvasive measurement of systolic blood pressure using photoplethysmography

Background  

Automatic measurement of arterial blood pressure is important, but the available commercial automatic blood pressure meters, mostly based on oscillometry, are of low accuracy.     

Automatic noninvasive measurement of systolic blood pressure using photoplethysmography

Background

Systolic blood flow has been simulated in the abdominal aorta and the superior mesenteric artery. The simulations were carried out using two different computational hemodynamic methods: the finite element method to solve the Navier Stokes equations and the lattice Boltzmann method.

Results

We have validated the lattice Boltzmann method for systolic flows by comparing the veloCity and pressure profiles of simulated blood flow between methods. We have also analyzed flow-specific characteristics such as the formation of a vortex at curvatures and traces of flow.

Conclusion

The lattice Boltzmann Method is as accurate as a Navier Stokes solver for computing complex blood flows. As such it is a good alternative for computational hemodynamics, certainly in situation where coupling to other models is required.