Inquiries into psychiatry: Chelmsford and Townsville.
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Australia↗
Biomedical subjects
B Boettcher
Publications and source records attributed to B Boettcher.
Development of human ABO blood group A antigen on Escherichia coli Y1089 and Y1090.
Studies by other workers have shown that some strains of Escherichia coli have surface antigens analogous to the human blood group ABH antigens, and that these are carbohydrates associated with membrane lipopolysaccharides. This study has demonstrated that E. coli strains Y1089 and Y1090 possess the H antigen, which can be converted to the A antigen by incubation with A-transferase (N-acetyl-galactosaminyl transferase) and A-sugar (UDP-N-acetyl-galactosamine). Such cells will then form mixed agglutinates with human A red cells and human polyclonal (but not mouse monoclonal) anti-A antibodies. E. coli Y1089 and Y1090 have endogenous enzymes that use the A-sugar (in the absence of A-transferase) to produce a variant A antigen. Cells expressing this variant antigen adsorb anti-A antibodies but do not participate in mixed agglutination with human group A red cells. It is estimated that E. coli Y1089 and Y1090 possess approximately 5000 H epitopes per cell that can be converted to A epitopes.
ABO Blood-Group System↗
Comparison of the SpermMar test with currently accepted procedures for detecting human sperm antibodies.
To eliminate the possibility of immunological infertility in spontaneously infertile and re-anastomosed men, a screening test that can be applied directly to semen is desirable. The SpermMar test is one such possibility. In this study, indirect tests for sperm antibodies using the commercial SpermMar test have been applied to a panel of sera whose reactions in the tube slide agglutination test (TSAT), gelatin agglutination test (GAT) and sperm immobilization test (SIT) for sperm antibodies are well characterized. The results from the SpermMar tests are compared directly with those obtained from Immunobead tests carried out at the same time. Results from screening tests performed on 30 sera confirmed complete correspondence between the GAT, SpermMar and Immunobead tests. When sera were titrated, the Immunobead test proved slightly more sensitive than the GAT and the SpermMar test was slightly more sensitive than the Immunobead test. The SpermMar test proved easier to use and to assess than the Immunobead test and it is recommended for consideration as a screening procedure for sperm antibodies despite the fact that at this stage only IgG antibodies can be detected.
Autoantibodies↗
A difference in the proteins found in young adults of inbred strains of Drosophila melanogaster which correlates with genetically-determined, long or short life span.
One-dimensional electrophoresis was performed on extracts of flies collected from across all ages. Protein gel patterns were compared for two strains of Drosophila melanogaster with distinctly long and short adult life spans that result from different alleles of longevity genes. An inter-strain difference was observed in the changes in protein pattern in the 77 kDa region in period of day 0-5 after emerging. We propose that the protein involved is a product of autosomal longevity alleles A1 and A2 at the Jm A locus and is related to development of longevity potentials in the preimaginal stage.
Animals↗
Purification and characterization of a protein associated with genetically-determined longevity difference in Drosophila melanogaster.
Earlier studies have shown a correlation between the presence of a 77 kDa protein in the proteins extracted from young adult Drosophila melanogaster (D.m.) and the autosomal longevity allele. A2 at the JmA locus. In this study, a 77 kDa protein has been isolated from pupae of D.m. of a long-lived strain of genotype A2A2, and was purified by DEAE chromatography, ConA column chromatography, and two cycles of gel filtration. The purified protein has a molecular weight of 76,600 (by SDS-PAGE), an isoelectric point of pH 6.5, and molar extinction coefficient A(280(1%) = 18.3. It is a glycoprotein containing 3.3% hexose. Supplementing the food of D.m. with the purified protein at 5 x 10(-4) micrograms/ml, beginning at day 5 after emergence, resulted in an increase in the survival rate and maximal life span of both short-lived and long-lived strains of D.m.
Animals↗
Relationship between genotypes of longevity genes and developmental speed in Drosophila melanogaster.
Hatching time (the period between egg-laying and hatching) and emerging time were surveyed and their relationship with the adult life span was investigated. A relationship between emerging time and adult life span was clearly evident: early emergers were often long-lived. This relation is considered to have a genetic basis because all the larvae in a group were bred in the same culture bottle. Thus, the longevity genes involved also appear to have control over the rate of development. No significant relation was observed between hatching time and adult life span or between hatching time and emerging time. These results suggest that the function of the longevity genes begins at the larval or pupal stage before emergence, and that adult life spans differentiate at this time.
Animals↗
Cytoplasmic influence on the expression of nuclear genes affecting life span in Drosophila melanogaster.
In earlier studies we have found that the difference between short and long life spans of two inbred strains of Drosophila melanogaster is controlled by nuclear major genes. The present study has revealed a cytoplasmic factor that influences the expression of the nuclear longevity genes. The factor shows a typical maternal inheritance and is considered to be an extranuclear gene, such as mitochondrial DNA (chondriome). This paper marks the discovery of two basic forms of inheritance, nuclear and extra-nuclear, in the genetics of life span of D. melanogaster. These findings suggest that further studies, including genetic engineering, on longevity and aging might enable direct manipulation of these characters.
Animals↗
Conversion of the human blood group H antigen to A antigen in vitro.
A-transferase (N-acetylgalactosaminyl transferase) was purified from human group A plasma using Sepharose 4B affinity chromatography. Human anti-A antibodies were purified from human serum by adsorption to an immunosorbent column and heat elution in order to detect the A antigen. Conditions appropriate for the development of the A antigen on O red cells were examined and several buffer systems were found to be equally effective. Expression of the developed A antigen was found to be similar to that on group A red cells, indicating that the system in vitro has similar activity to the system in vivo. The H antigen from human saliva was coupled to Sepharose 4B or adsorbed to a nitrocellulose membrane. The A antigen was able to be developed on these materials by the action of group A-transferase. The procedures enabled the identification in vitro of sugar-transferase activities which can be useful in studies within the A,B,H antigen system or other carbohydrate antigen system.
ABO Blood-Group System↗
Transcription initiation and nuclease-sensitive sites upstream of the epsilon-globin gene in K562 cells are related to poly (dA).poly (dT) sequences.
Previous studies have documented transcription initiation sites and nuclease hypersensitive sites upstream of the epsilon-globin canonical cap site in K562 cells. The upstream transcription initiation sites coincide with some of the nuclease hypersensitive sites. Comparison of the positions of the upstream transcription initiation and the nuclease hypersensitive sites with the nucleotide base order shows that these upstream sites fall significantly closer to poly (dA).poly (dT) tracts than can reasonably be accounted for by chance. It is concluded that these sites are related to the occurrence of poly (dA).poly (dT) tracts of at least five base pairs. Other studies have related some particular functional properties to poly (dA).poly (dT) tracts. Additionally, poly (dA).poly (dT) tracts have been shown to have unusual physical characteristics and to produce an intrinsic bending of the DNA molecules in which they are located. This study indicates that poly (dA).poly (dT) tracts can provide access to DNA for RNA polymerases and induce a DNA conformation recognized by DNase I or S1 nuclease.
Base Sequence↗
Influence of temperature on the inheritance of adult life span in Drosophila melanogaster.
Mating experiments were performed at 27 degrees C, 22 degrees C, and 17 degrees C, to investigate the inheritance of adult life span of highly inbred strains of Drosophila melanogaster. Effects of temperature difference were quantitatively analyzed at the genotypic level. In the temperature range of 17-27 degrees C the autosomal longevity alleles, A1 and A2, exerted major effects. Their effects produced longer life spans as the temperature decreased. The sex-linked longevity alleles, X1 and X2, played a secondary role in influencing life span, and they displayed different effects at different temperatures. Each genotype showed correspondence to the life span expected from the combinations of these longevity genes at the respective temperatures. The genetic loci controlling life span in these inbred strains were named JmA and JmX from "Ju-myo" which means life span or longevity in Japanese.
Animals↗
Antispermatozoal antibodies in three men with infertility due to congenital aplasia of the vasa deferentia.
Men presenting with azoospermia due to aplasia of the vas deferens have commonly been considered to be infertile without hope of treatment. With improved methods of artificial insemination however, and more particularly with the advent of in vitro fertilization, it has been suggested that unusable spermatozoa may be able to be drawn from the epididymes of such men so that fertilization is achieved. The clinical situation of such men is analogous to that of long term vasectomised patients, 60% of whom are known to produce antibodies to spermatozoa which would interfere with the fertilization process. It was therefore decided to attempt to draw fluid from the epididymes of three such patients and at the same time conduct immunological studies on their sera, seminal fluid and, where available, epididymal fluid. Unfortunately, the spermatozoa obtained from all three men lacked sufficient progressive motility for use in in vitro fertilization. In addition, all men had antispermatozoal antibodies in their sera. Two of them also had antispermatozoal antibodies in their epididymal fluid and on their sperm, one at the same titer as in his serum. Since it is known that antibodies coating sperm reduce the changes of fertilization it is suggested that their presence should be assessed in all such men being considered for treatment. In addition, these studies demonstrate that antispermatozoal antibodies can enter the male tract at the level of the epididymis or higher and there were strong suggestions of local antibody production at this level in the tract.
Adult↗
Contaminating antibodies may produce unexpected reactions in counter-current immunoelectrophoresis.
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Antibodies↗
Synthesis of L-2-oxothiazolidine-4-carboxylic acid.
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Indicators and Reagents↗
Antispermatozoal antibodies in human follicular fluid.
The possibility of antispermatozoal antibodies in women having significant effects in the higher regions of the female reproductive tract has been investigated. Follicular fluids (FF) and sera taken at the time of oocyte recovery from women undergoing in vitro fertilisation and embryo transfer (IVF-ET) were tested for the presence of antispermatozoal antibodies, and the concentrations of IgM, IgG, IgA, and complement C3 were determined. The concentrations of immunoglobulins and C3 in FF were consistent with transudation from serum inversely proportional to molecular weight. Titres of agglutinating and immobilizing antibodies in FF were usually one or two dilution steps below those of serum except where immobilizing activity was associated with IgM. IgG:IgA ratios were lower in FF from women with antispermatozoal antibodies, suggesting local production or enhanced transudation of IgA; however, a secretory component could not be detected in any of the follicular fluids in this study. Two women with antispermatozoal antibodies and infertility in excess of 5 years had successful IVF-ET and have delivered healthy infants.
Antibody Specificity↗
Common specificities of auto- and iso-antibodies to human spermatozoa.
The specificities of antispermatozoal antibodies in humans were compared using the ability of F(ab')2 fragments prepared from sera containing spermatozoal antibodies to block access to antigenic sites on spermatozoa. Reciprocal blocking experiments were carried out on a panel of 13 sera which came from both men and women, had different modes of agglutination, and came from widely separated population centers. The blocking experiments confirmed that specificities of antispermatozoal antibodies bear little relation to those suggested by observed modes of agglutination. F(ab')2 fragments from head-agglutinating sera could inhibit the immobilizing activity of a tail-agglutinating sera and vice versa. Similarly, the sera from men and women could inhibit each other, as could sera collected from patients living in widely separated localities. It is concluded that there are more than one, but a limited number, of antigens on the spermatozoal surface capable of generating antibodies with antifertility effects. It is also concluded that these antigens occur all over the sperm surface but may be concentrated in certain areas and that the observed modes of agglutination depend at least as much on the characteristics of the antibodies as on their specificities.
Antibody Specificity↗
Mixed-lymphocyte culture response in a related and an unrelated Australian population.
In 256 related combinations in an Australian Caucasian population, the relative responses in one-way mixed-lymphocyte cultures can be divided into four different groups: (i) HLA zero-haplotype different; (ii) HLA-D homozygous-versus-heterozygous; (iii) HLA one-haplotype different: and (iv) HLA two-haplotype different. The median relative responses of the groups were 0.78%, 20%, 64% and 86.5%, respectively; 17.7% of HLA-A, HLA-B identical siblings were found to stimulate significantly in mixed-lymphocyte culture, and 6.3% of HLA one-haplotype different combinations had weak responses. The median relative response of 225 unrelated random combinations was 100%. One mixed-lymphocyte culture combination in this group gave a relative response of 20%, which was found to be a HLA-D homozygous-versus-heterozygous response. A relative response of 20% in mixed-lymphocyte cultures may be taken to indicate relative HLA-D compatibility and would, therefore, predict a favourable outcome in kidney transplantation. The use of mixed-lymphocyte cultures as a routine in selecting suitable donors in living related transplants and, retrospectively, in monitoring the results of cadaveric transplants, is advocated.
Graft Survival↗
Effects of cholera toxin and 5'-guanylylimidodiphosphate on human spermatozoal adenylate cyclase activity.
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Adenylyl Cyclases↗