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The analysis and segmentation of articular cartilage magnetic resonance (MR) images belongs to one of the most commonly routine tasks in diagnostics of the musculoskeletal system of the knee area. Conventional regional segmentation methods, which are based either on the histogram partitioning (e.g., Otsu method) or clustering methods (e.g., K-means), have been frequently used for the task of regional segmentation. Such methods are well known as fast and well working in the environment, where cartilage image features are reliably recognizable. The well-known fact is that the performance of these methods is prone to the image noise and artefacts. In this context, regional segmentation strategies, driven by either genetic algorithms or selected evolutionary computing strategies, have the potential to overcome these traditional methods such as Otsu thresholding or K-means in the context of their performance. These optimization strategies consecutively generate a pyramid of a possible set of histogram thresholds, of which the quality is evaluated by using the fitness function based on Kapur's entropy maximization to find the most optimal combination of thresholds for articular cartilage segmentation. On the other hand, such optimization strategies are often computationally demanding, which is a limitation of using such methods for a stack of MR images. In this study, we publish a comprehensive analysis of the optimization methods based on fuzzy soft segmentation, driven by artificial bee colony (ABC), particle swarm optimization (PSO), Darwinian particle swarm optimization (DPSO), and a genetic algorithm for an optimal thresholding selection against the routine segmentations Otsu and K-means for analysis and the features extraction of articular cartilage from MR images. This study objectively analyzes the performance of the segmentation strategies upon variable noise with dynamic intensities to report a segmentation's robustness in various image conditions for a various number of segmentation classes (4, 7, and 10), cartilage features (area, perimeter, and skeleton) extraction preciseness against the routine segmentation strategies, and lastly the computing time, which represents an important factor of segmentation performance. We use the same settings on individual optimization strategies: 100 iterations and 50 population. This study suggests that the combination of fuzzy thresholding with an ABC algorithm gives the best performance in the comparison with other methods as from the view of the segmentation influence of additive dynamic noise influence, also for cartilage features extraction. On the other hand, using genetic algorithms for cartilage segmentation in some cases does not give a good performance. In most cases, the analyzed optimization strategies significantly overcome the routine segmentation methods except for the computing time, which is normally lower for the routine algorithms. We also publish statistical tests of significance, showing differences in the performance of individual optimization strategies against Otsu and K-means method. Lastly, as a part of this study, we publish a software environment, integrating all the methods from this study.

Wavelet transform (WT) is a commonly used method for noise suppression and feature extraction from biomedical images. The selection of WT system settings significantly affects the efficiency of denoising procedure. This comparative study analyzed the efficacy of the proposed WT system on real 292 ultrasound images from several areas of interest. The study investigates the performance of the system for different scaling functions of two basic wavelet bases, Daubechies and Symlets, and their efficiency on images artificially corrupted by three kinds of noise. To evaluate our extensive analysis, we used objective metrics, namely structural similarity index (SSIM), correlation coefficient, mean squared error (MSE), peak signal-to-noise ratio (PSNR) and universal image quality index (Q-index). Moreover, this study includes clinical insights on selected filtration outcomes provided by clinical experts. The results show that the efficiency of the filtration strongly depends on the specific wavelet system setting, type of ultrasound data, and the noise present. The findings presented may provide a useful guideline for researchers, software developers, and clinical professionals to obtain high quality images., Competing Interests: The authors have declared that no competing interests exist.

In the area of musculoskeletal MR images analysis, the image denoising plays an important role in enhancing the spatial image area for further processing. Recent studies have shown that non-local means (NLM) methods appear to be more effective and robust when compared with conventional local statistical filters, including median or average filters, when Rician noise is presented. A significant limitation of NLM is the fact that thy have the tendency to suppress tiny objects, which may represent clinically important information. For this reason, we provide an extensive quantitative and objective analysis of a novel NLM algorithm, taking advantage of pixel and patch similarity information with the optimization procedure for optimal filter parameters selection to demonstrate a higher robustness and effectivity, when comparing with NLM and conventional local means methods, including average and median filters. We provide extensive testing on variable noise generators with dynamical noise intensity to objectively demonstrate the robustness of the method in a noisy environment, which simulates relevant, variable and real conditions. This work also objectively evaluates the potential and benefits of the application of NLM filters in contrast to conventional local-mean filters. The final part of the analysis is focused on the segmentation performance when an NLM filter is applied. This analysis demonstrates a better performance of tissue identification with the application of smoothing procedure under worsening image conditions.

The lectin anti-AHP (Helix lectin) obtained from the albumen gland of an edible snail, Helix pomatia, was used for the identification of group C streptococci. All 1,045 strains of group C streptococci (S. equisimilis, S. zooepidemicus, and S. dysgalactiae) were agglutinated with the Helix lectin, but none of the 12,264 strains of group A, 1,346 strains of group G, 330 strains of group B, and 121 strains of other streptococcal groups was not. A few strains of S. equisimilis which belongs to group C have on the cell surface specific T antigen of group A streptococci, but it did not affect the agglutination with Helix lectin. Some strains of S. milleri carrying or not carrying group G specific carbohydrate and S. sanguis with group H antigen were agglutinated with the Helix lectin (Anti-AHP). This suggests that terminal N-acetyl-D-galactsamine of the cell-wall carbohydrate of these bacteria reacts with the Helix lectin (Anti-AHP). Therefore, the Helix lectin is a very useful tool for identification of group C streptococci.

We have evaluated oligonucleotide hybridization and amplification techniques with regard to quantity and quality of genomic DNA that is under investigation in practical forensic case work. In order to obtain sufficient information from analyzing stain material, we use hypervariable simple repeat sequences for individualization, which occur in all eukaryotic genomes. For the analysis of larger amounts of stains (greater than 500 ng DNA) the multilocus probes (CAC)5/(GTG)5* are superior because of their discrimination potential--provided that the hybridizing DNA is of high molecular weight. The less discriminating probes (CT)8 and (GACA)4 are more sensitive (minimal amount: 100ng DNA) and still informative when the DNA is degraded. To increase the sensitivity of forensic stain analysis in special cases we have used the polymerase chain reaction technique to amplify hypervariable simple (gt)n/(ga)m repeat structures from the intron 2 of HLA-DRB genes. Largely independent of the starting amount of DNA and independent of the degradation status, we were able to generate discriminating DNA fragments, which can be used to type (i) microstains and (ii) totally degraded material including human mummy DNA.

On the basis of some models (bacteria and animal blood groups), it was demonstrated that monoclonal antibody-preparations obviously possess a much higher specificity against the ABO-properties of human than the usual human antisera or lectins. The behaviour of polyclonal and monoclonal reagents for ABO-determination should now be tested in comparative studies using contaminated blood stain material. The results presented in this paper suggest advantages in using monoclonal antibodies.

The use of oligonucleotide fingerprinting is evaluated in practical forensic work, using both artificially and systematically produced stains as well as actual case work material. The probes (CAC5/(GTG)5 are superior because of their individualizing potential in comparatively fresh specimens with little DNA degradation, whereas (GACA)4, still produces substantial information when high molecular weight DNA is lacking. The overall limitations and the advantages of this technology are discussed in detail and compared to the classical minisatellite probes.

More than 150 years ago the foundations were laid for the so-called HERBST effect which was subsequently forgotten. In the sixties the phenomenon was rediscovered by VOLKHEIMER at the Charité Hospital in Berlin and then reviewed through many experiments and publications. What is meant by the HERBST effect? If an experimental animal or even human being is given a larger amount of maize starch or also biscuits or some other products containing starch, starch bodies can be detected rapidly in venous blood already after minutes or half an hour later and in the urine after one hour and later. The term "persorption" has been coined for this interesting phenomenon. It is indeed surprising that it has met with so little attention. As a matter of fact, it constitutes the basis for our understanding of peroral immunization and of allergies. In the same way, feeding of carbon particles results in their appearance and detection in blood, kidney and urine. The same result is obtained by the intake of diatoms and what is even more important with meat fibres. I hope you are aware of the implications. When Professor NAGAI stayed in Berlin, we tried to receive the phenomenon. Since only a few cell nuclei are necessary for "genetic fingerprinting" we thought that after intake of 200 or 400 g of raw meat the type of food eaten could be determined from the urinary sediment by means of the fingerprint method which would be of forensic significance. Therefore, we eat meat and raw liver and examined the urinary sediment.(ABSTRACT TRUNCATED AT 250 WORDS)

The results of the application of the C3 system to 155 cases of disputed paternity are presented. In this preselected material (none of the 234 accused men could be excluded by any of the usual markers of red blood cells and serum) 23 men were excluded. Of these 23 exclusions, 17 could be examined in the HLA-system and were confirmed by this system. In 211 mother-child pairs no theoretically impossible combinations were observed.

Saliva of 310 persons were examined for their ability to agglutinate 33 streptococcal strains of the groups A-T. It was found that the saliva of persons with blood group O agglutinated significantly more often streptococci of strain G9 than the saliva of persons with blood group A (33.3%, and 18.75% resp., p less than 0.01). A statistical significant difference between persons of blood group B and O, or A and B did not exist. The agglutination reactions were caused probably by unspecific immunoglobulins because this strain G9 binds unspecifically human IgG. It is known, that some streptococcal strains of the groups A, B, C, D, and G contain receptors for the Fc-fragment of IgG and/or IgA. The results demonstrate that persons of the blood group O secrete more often immunoglobulin than those with blood group A.

Anti-streptococcal T4 titres in human sera tend to be higher in normal sera of the Hp type hp 2-2 than in normal sera of hp 2-1 subjects. If the sera are heated above a temperature of 50 degrees C the difference disappeared and the titres are reduced. When heating sera to 63 degrees for 10 min no agglutination activity for T4 streptococci can be observed.

By testing 167 human sera a surprising dimorphism could be found. All sera of the haptoglobin type hp 1-1 belong to the group with an anti-G streptococci titer in the range of 1:0 to 1:10 whereas sera of the types hp 2-1 and hp 2-2 do have titers in the range between 1:200 and 1:3200 or more. All tests are carried out in the double blind technique.

The antibody-like activity of haptoglobin types hp 2-2 and hp 2-1 for streptococci having the T4 antigen is not reduced by saturation with hemoglobin.

The relationship between haptoglobin type and the agglutinability of some group G streptococci, which was observed in humans, could also be demonstrated in animal sera. In humans the haptoglobin type Hp 1-1 is correlated with a lacking or very low agglutinability. Sera of 10 rhesus monkeys showed Hp-type 1-1 and agglutinated the streptococci only to dilutions of the serum up to 1:4. The sera of 48 pigs contained an Hp 1-1 like type and a streptococcus agglutination titer of max. 1:10. Seven ahaptoglobinaemic sera gave the same values. Fifty examined sera of rabbits showed also an Hp 1-1 like pattern and did not agglutinate or in undiluted state only.

For the last 25 years, antisera for testing P1 in man have been obtained by i.v. injections in goats using hydatid cyst fluid from livers of pigs infected by Echinococcus granulosus. Due to the fact that this antigen has become very rare today, efforts have been made by the authors to substitute it by different antigens and to save antigen by modifying the technique of immunisation as well. By this, very high titres up to 1:4096 could be reached after specification absorption.

After intravenous immunization of six rabbits with washed red cells from a pigeon (columba domestica), anti-P1 of very good quality was obtained after 8-12 injections. The sera indicate human blood cells of type P1 equally well as do anti-P1 of goat (immunized with echinococci cyst fluid).

In regard to the undecided immunological role of protein polysaccharides (of the glycosaminoglycan type) for pathogenesis of connective tissue diseases a protein polysaccharide-containing extract from bovine nasal cartilage was tested by the absorption method, precipitation and immunization. An A-like effect of the extract was found.

Human sera are able to agglutinate latex particles sensitized with antihaptoglobin serum produced from sheep. The agglutination depends on the haptoglobin types. Similar to the agglutination of T4-streptococci the titer of Hp 1-1 is very low and the titers of sera of the types Hp 2-1 and Hp 2-2 are 1:160 or higher.

A relationship was found between the haptoglobin types of human sera and the agglutinability of some strains of group G streptococci. Sera with the haptoglobin types Hp 2-2 and Hp 2-1 agglutinate these streptococci to high titers, from 1:200 up to more than 1:6400. On the other hand, the sera with haptoglobin type Hp 1-1 agglutinate not more than up to titers of 1:16 (mostly lower). Out of 102 strains of group G streptococci only 3 showed this characteristic phenomenon. This study was undertaken in order to elucidate whether the Hp 2-2 and Hp 2-1 proteins have antibody activity. Incubation of Hp 2-2 or Hp 2-1 sera with antihaptoglobin antisera or with anti-Hp 2-antiserum did not change the agglutinating activity but the haptoglobin was eliminated from the sera. Absorption of Hp 2-2 and Hp 2-1 sera with these group G streptococci lowered the titers significantly but the haptoglobins are detectable as in the non-absorbed sera. Sera with haptoglobin 1-1 contain an inhibitor. Mixing of Hp 2-2 and Hp 2-1 sera with high agglutinating titers with Hp 1-1 sera (low titers) was followed by a significant decrease of the titer.

The immunological comparison of human and equine Gc proteins showed partial identical reactions between both species. Immunizations of goats and rabbits with horse serum produced antisera able to recognize human Gc proteins.

Sera of 157 baboons (Papio hamadryas and P. anubis) 21 chimpanzees (Pan troglodytes) five orang utans (Pongo pygmaeus) three mountain gorillas (Gorilla gorilla beringei) and three gibbons (Hylobates lar lar) were examined for the content of antistreptolysin O, antidesoxyribonuclease B, for the presence of rheumatoid factors as well as for the level and type of haptoglobin. The mean antistreptolysin O titer (AST) in baboons was 106 ASU +/- 18 in dextransulfate absorbed sera ("real" AST) and 182 ASU +/- 34 in non-absorbed sera. The mean decrease after absorption was 20% (i.e., 20% inhibitor + 80% antistreptolysin O), a value that is lower than previously found in rhesus monkeys (55%) or in man (40%). Raised values of anti-DNase B were found in two baboons only, and none of the sera of that species displayed presence of rheumatoid factors. In chimpanzees, the mean AST was 68 +/- 29 in absorbed and 87 ASU +/- 57 in non-absorbed sera. Anti-DNase B was raised in three animals, and in two cases the increase was correlated with raised AST. Of 19 chimpanzee sera examined, 13 were found to contain antigammaglobulins ("rheumatoid factors") the titers of which reached 1:64 or more. All primate sera tested so far showed haptoglobin type 1-1 or Hp 1-1-like patterns. The haptoglobin level in chimpanzees and baboons was comparable to that established in man; in rhesus monkey, on the other hand, much lower values (40-62 mg/100 ml) or ahaptoglobinemia were observed. The sera of all monkeys and apes tested so far showed a very low (undiluted, or up to 1:10 titer at most) agglutinating activity against T4-antigen-carrying streptococci. This is in agreement with our observations made previously which indicated that human or animal sera of haptoglobin type 1-1 agglutinated streptococci to a much lower degree than type Hp 2-2 or type Hp 2-1 sera.

The haptoglobins in man and in mammals are agglutinin-like-substances for streptococci having the T4 antigen. The kind of the agglutinin-like behaviour depends on the genetic type of the haptoglobins. Haptoglobins of the types Hp 2-2, Hp 2-2 like and Hp 2-1 are hightitred complete agglutinins (titre in the range between 1:200 up to 1:3000 and higher) whereas haptoglobins of the type Hp 1-1 are "blocking antibodies". - The steps of the discovery and evidence are presented in detail. Different questions dealing with the clinical significance are discussed.

The relationship between haptoglobin type and titer of agglutination against streptococci carrying the T4-antigen was examined in 100 pairs of sera (mother/child). In healthy pregnant women high titers were predominant in individuals of haptoglobin type 2--2. Lower titers were found in sera of women with diseases during pregnancy. In 4% of the newborns only the haptoglobin type could be recognized. In comparison of maternal and neonate titers of agglutination pointed out the antibody-like activity of haptoglobins.

Within a sample of 6107 non related subjects no dependency of the Gm-types from the Rh-phenotypes could be observed. These data as well as the results of linkage studies do not suggest the localisation of the Gm-loci on chromosome 1.

The inquiry for the sense of blood group polymorphisms (enzyme groups and serum groups included) and their significance for the constitution and also disposition to diseases is for the time being absolutely legitimate. But it is shown that the field--scarcely a new hereditary blood factor has been detected--becomes a subject of speculations, possibly of the teleological kind: "For which purpose is the factor existing?", or even "Why has God made up the factor?". The hypotheses developing on that are often extremely suggestive and incorrect hypotheses on the first opportunity sometimes reappear like a "cork-tumbler". Finally only a few hard facts remain. This is shown with the help of the systems AB0, Duffy, HLA, Hp and Pi.

A significant correlation was found between levels of haptoglobin in sera from Indonesian patients with tuberculosis and the extent to which these sera suppressed mitogen-driven activation of normal lymphocytes in vitro. As in a previous study we showed that there was an inverse relationship between haptoglobin levels and the circulating lymphocyte count in the same group of patients, it is now suggested that this protein has an immunoregulatory role in tuberculosis. Similar observations have been made by other workers on patients with cancer. There was no difference in the distribution of the 3 allotypes of haptoglobin in patients and healthy subjects nor was there any association between such allotypes and the lymphocyte count, the dermal reactivity to tuberculin or the degree of suppression.

In systematic investigations we found a relationship between the haptoglobin types of human sera and the agglutinability of some group-G streptococcal strains. Sera with the haptoglobin type Hp 1-1 do not agglutinate these strains (or with low titres up to 1:16 only). On the other hand sera with the haptoglobin types Hp 2-1 or Hp 2-2 agglutinate the streptococci with titres from 1:200 to 1:3,200 (or more). The aspects resulting from these findings were discussed in detail. They may have among others practical consequences for the forensic medicine and the role of the haptoglobins must be thought over again.

The haptoglobins in man and in mammals react with streptococci bearing the T4-antigen. Hp 2-2 and Hp 2-1 react with high titres like complete agglutinins while Hp 1-1 acts like a blocking antibody. It is surprising to observe the similarity of the behaviour of the haptoglobins and of IgG and IgM. Streptococci carrying Hp 1-1 yield a positive Coombs-test. The Coombs-serum however, is an anti-human-haptoglobin-body from sheep. By means of supplements it has been possible to increase partly considerably the titres of Hp 2-1 and Hp 2-2 against the streptococci.

Some strains of beta-haemolytic streptococci were agglutinated with high titers (1:200-1:6400) by human sera of the haptoglobin types 2-2 and 2-1. No agglutination or with low titers (up to 1:20) was observed with sera of the haptoglobin type 1-1. This reactivity depends from the contents of Streptococcus pyogenes T-antigens of the T-complex 4,24... This T4-antigen is present in group A streptococci (Strep. pyogenes) of the types 4, 24, 26, 28, 29, 46, 48 and 60 but it may be present also in some strains of streptococcal groups C and G. During a 10-year period we isolated 12 strains of Strep. equisimilis (group C) carrying the T-4 antigen (1.6%) and 50 group-G streptococci with T-4 antigen (6.4%) of all group G streptococci). These strains were agglutinated without an exception with high titers by Hp 2-2 and Hp 2-1 sera but not by sera of the haptoglobin type 1-1. The same particuliarity was shown by Streptococcus pyogenes types of the T-complex 4, 24... One strain of type 26 (BC 179) has no T antigen and therefore it was not agglutinated in the above mentioned manner. The phenomenon depends from the medium; it occurs after cultivation of the streptococci in Pope broth or in meat-infusion with glucose but not or only reduced in beef heart-proteose-medium. The agglutination reaction is caused by the haptoglobin but not by agglutinins against the T4-antigens.