Biomedical subjects
Publications and source records attributed to K Nielsen.
The histopathological changes in the synovial membrane of bursa podotrochlearis are described in horses with navicular disease. The changes are compared to the histopathological findings in synovial membrane of arthrotic pastern joints in horses and of arthrotic hips in man. A high degree of concordance is demonstrated and this suggests that navicular disease is an arthrotic disease.
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Macroscopic specimens on the anal canal from 22 patients with colorectal carcinoma and 5 patients with anal canal carcinoma were investigated by stereomicroscopy after whole-mount staining with alcian blue. The specimens were thereafter cut up systematically and prepared for conventional light microscopy to correlate stereomicroscopic and histologic findings. The results show that different surface relief and colour intensity correspond to different types of surface epithelium. Stereomicroscopy, however, did not show differences between various histological types of anal canal carcinoma.
Seventeen out of eighteen patients, who underwent the modified Bristow operation for anterior recurrent dislocation of the shoulder, were followed up after a mean observation time of 52 months. Fourteen patients were satisfied with the result. There were no redislocations. The principal limitation in range of motion was loss of some external rotation. Eight patients had non-union between the bone transplant and the glenoid rim, and four of these had complications related to the screw. Two had loosenings and two had fractures of the screw. Non-union without screw complications appeared not to influence the end result. The reasons for the complications seem to be technical problems concerning fixation and bone union of the coracoid process.
The presence of carcino-embryonic antigen (CEA) was studied in 92 consecutive cases of gastric adenocarcinoma, using the two-layer conjugated immunoperoxidase technique. Three characteristic patterns of CEA localization were identified. Type I: Intracytoplasmatic granules covering the entire cytoplasm of the malignant cells. Type II. Linear or granular deposits along the glycocalyx or in the apical cytoplasm of the malignant cells. Type III: Tumour cells negative for CEA or only showing a very weak reaction in a few cells. These CEA patterns were significantly related to the histogenetic classification of gastric adenocarcinomas proposed by Mulligan & Rember. The majority of the "mucus cell carcinomas" showed the type I CEA pattern. "Intestinal cell carcinomas" predominantly showed the type II CEA pattern and the "pyloro-cardiac gland carcinomas" the type III CEA pattern. The significance of the CEA patterns in respect of the histogenetic classification is discussed.
The binding site of B. abortus involved in nonspecific or false-positive agglutination by bovine serum was shown to be Ca++-independent in that binding of Ca++ by the chelating reagent DP2TA did not decrease titers. The reduction in agglutination by EDTA, EGTA, and DPTA was thought to be related to a common structural characteristic of these chelating reagents not exhibited by EDDA and DP2TA or to a lesser extent by DTPA. Removal of antigenic entities from the cell by the chelator was excluded as the cause of agglutination inhibition because agglutination by nonspecific IgM was not influenced by repeated washing of B. abortus by EDTA. The action of the chelators on the cell-agglutinin interaction was hypothesized to be a result of their competition with a receptor site on the cell for binding of the nonspecific or biochemically altered bovine IgM.
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It was demonstrated by a radioimmunoassay procedure that Brucella abortus agglutinins from noninfected cattle sera, absorbed to B. abortus antigen and eluted with ethylenediaminetetraacetic acid (EDTA), was immunoglobulin M that bound to that bacterium by its Fc portion. The EDTA-eluted immunoglobulin M agglutinated intact B. abortus cells but not erythrocytes treated with B. abortus lipopolysaccharide. The specificity of the EDTA-eluted immunoglobulin was for B. abortus, although a small titer to Yersinia enterocolitica serotype O:9 was observed. In contrast, immunoglobulin M purified from the serum of a cow injected 7 days previously with heat-killed B. abortus bound to the antigen by its Fab portion, was not labile to EDTA treatment, cross-reacted extensively with Y. enterocolitica serotype O:9, and agglutinated various other bacterial antigens and normal erythrocytes.
Plaster of Paris and Hexelite, a new thermoplastic bandage, were compared in the treatment of 183 patients with malleolar fractures, Colles' fractures or distortions of the finger joints. There were no statistically significant differences between the two types of bandages taking into account the strength of the bandage, the amount of skin damage and the patient's opinion of the bandage. Hexelite is seven times more expensive than plaster of Paris, and, in addition, is more difficult to handle. Hence its use has been discontinued.
A technique for producing specific antibovine IgG2 antibodies is described. The method relies on the abrogation of the class-specific antibody response of guinea pigs to bovine IgG1 by intravenous injection of goat serum immediately before immunisation in the foot pads with bovine IgG2 in adjuvant. Of the 10 resulting antisera, six were judged monospecific for IgG2 by immunoelectrophoresis but, of these, two antisera gave a very faint line in gel diffusion using IgG1 as the antigen. Radial immunodiffusion studies indicated that the strength of the antisera, using IgG2 as the antigen, was similar to antisera of guinea pigs not injected with goat serum before absorption with bovine IgG1. For guinea pigs injected with goat serum, using bovine IgG1 as an immunogen did not result in the production of subclass specific antisera, rather, the specificities were similar to those of animals not receiving goat serum. This data is compared to absorption studies of goat antibovine IgG1 and IgG2 antisera. The relationships of goat and bovine IgG subclasses are discussed.
A double immunodiffusion test for precipitins against Brucella antigen A2 was developed and applied to a variety of samples. The A2 precipitins were produced by a heifer infected with B. abortus strain 2308, cattle vaccinated with killed B. melitensis strain H38 or live B. abortus strain 19 and by a dog infected with B. canis. Precipitins were also detected in the second International Standard for anti-Brucella abortus serum, in several anti-B. canis sera and at low levels in one anti-B. ovis serum tested. Antisera produced in calves against Yersinia enterocolitica serotype 0:9 had no anti-A2 activity despite titers greater than or equal to 1/1024 and greater than or equal to 1/80 in standard Brucella agglutination and CF tests, respectively. The test for A2 precipitins lacked specificity as weak reactions were obtained with five of 295 sera from brucellosis-free herds. This test was relatively insensitive, detecting precipitins in only 16 of 24 sera from infected cattle and 27 of 54 sera positive by complement fixation and enzyme labelled antiglobulin tests performed with whole cell and smooth lipopolysaccharide antigens, respectively. The A2 precipitins were detected in nine sera from five cattle, in two infected herds, which were negative by agglutination and complement fixation tests.
Two methods are described for the partial purification of a high molecular weight, heat-resistant component (CO1) of sonicates of smooth and rough Brucella abortus which is precipitated by sera of some infected cattle. Method 1, a combination of gel filtration chromatography and polyacrylamide gel electrophoresis, was used to prepare CO1 from sonicates of a smooth field strain of B. abortus. Method 2, a combination of gel filtration chromatography and heat treatment, was used to obtain CO1, from sonicates of rough B. abortus strain 45/20. Rabbit antisera produced against CO1 prepared by either method contained only CO1 precipitins but were negative in standard agglutination and complement fixation tests conducted with whole cell antigens. Evidence is presented that CO1 is identical to Brucella antigen A2, and it is proposed that in future the designation A2 be employed.
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The application of the soluble antigen fluorescent test as a tool for serological investigation of influenza type A infection in wild birds was studied. The soluble antigen fluorescent antibody test is basically an indirect fluorescent antibody test except that an artificial matrix of cellulose acetate discs is used as a substrate for antigen and the test results are scanned and recorded by a fluorometer. THe influenza type A soluble antigen fluorescent antibody was obtained from concentrated and detergent disrupted virus particles, absorbed onto cellulose acetate discs. Anti-influenza sera were prepared in pheasants and ducks to A/turkey/Ontario/6118/67 and in pigeons to A/turkey/Ontario/6213/68. The antigen-antibody complex was detected by specific staining with monovalent or polyvalent fluorescein isothiocyanate conjugated rabbit anti-avian immunoglobulins. The soluble antigen fluorescent antibody test is a sensitive technique for the detection of specific influenza A antibodies in several avian species, and could be adapted for use in large scale surveys.
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