Detection of superior mesenteric vein thrombosis following splenectomy using real-time and Doppler sonography

Superior mesenteric vein thrombosis after splenectomy is very rare. In the case described of a patient presenting with acute abdominal pain the diagnosis was made primarily by real-time and Doppler ultrasonography. This reduced the time elapsing before it was recognized that angiography and subsequent thrombectomy were indicated.     

Cavernous hemangioma of the mediastinum

After presenting an own case of a cavernous hemangioma of the mediastinum, the clinical pattern, differential diagnosis, diagnostic procedure (computed tomography), and therapy of this rare tumor form are described.     

Kinetics of specific anti-influenza antibody production by cultured lymphocytes from patients with systemic lupus erythematosus following influenza immunization.

Specific antibody responses to influenza viral antigens produced by cultured peripheral blood mononuclear leucocytes stimulated with influenza virus or pokeweed mitogen (PWM) have been measured in seven patients with systemic lupus erythematosus (SLE) before and at time intervals after influenza immunization. Cells from two patients stimulated with influenza virus in vitro produced high levels of specific antibody 7 days after immunization. Cells from a third patient produced small amounts of specific antibody at day 14. No antibody was produced by cells from the remaining four patients. Responses were of short duration and were not detectable 1 month after immunization. Specific anti-influenza antibody was induced by PWM only from cells of those patients who responded to virus antigen although absolute levels of antibody produced were not as high. In six patients serum haemagglutination inhibiting antibody to influenza virus was measured, and all six had a greater than four-fold increase. The disparity between in vitro antibody production by peripheral blood mononuclear leucocytes and changes in serum antibody suggests that in patients with systemic lupus erythematosus, in vitro functions of peripheral blood lymphocytes do not reflect the immune system as a whole.     

Hepatic DNA adduct dosimetry in rats fed tamoxifen: a comparison of methods

Liver homogenates from rats fed tamoxifen (TAM) in the diet were shared among four different laboratories. TAM-DNA adducts were assayed by high pressure liquid chromatography-electrospray tandem mass spectrometry (HPLC-ES-MS/MS), TAM-DNA chemiluminescence immunoassay (TAM-DNA CIA), and (32)P-postlabeling with either thin layer ((32)P-P-TLC) or liquid chromatography ((32)P-P-HPLC) separation. In the first study, rats were fed a diet containing 500 p.p.m. TAM for 2 months, and the values for measurements of the (E)-alpha-(deoxyguanosin-N(2)-yl)-tamoxifen (dG-N(2)-TAM) adduct in replicate rat livers varied by 3.5-fold when quantified using 'in house' TAM-DNA standards, or other approaches where appropriate. In the second study, rats were fed 0, 50, 250 or 500 p.p.m. TAM for 2 months, and TAM-DNA values were quantified using both 'in house' approaches as well as a newly synthesized [N-methyl-(3)H]TAM-DNA standard that was shared among all the participating groups. In the second study, the total TAM-DNA adduct values varied by 2-fold, while values for the dG-N(2)-TAM varied by 2.5-fold. Ratios of dG-N(2)-TAM:(E)-alpha-(deoxyguanosin-N(2)-yl)-N-desmethyltamoxifen (dG-N(2)-N-desmethyl-TAM) in the second study were approximately 1:1 over the range of doses examined. The study demonstrated a remarkably good agreement for TAM-DNA adduct measurements among the diverse methods employed.     

New x-ray tube performance in computed tomography by introducing the rotating envelope tube technology

The future demands of computed tomography imaging regarding the x-ray source can be summarized with higher scan power, shorter rotation times, shorter cool down times and smaller focal spots. We report on a new tube technology satisfying all these demands by making use of a novel cooling principle on one hand and of a novel beam control system on the other hand. Nowadays tubes use a rotating anode disk mainly cooled via radiation. The Straton x-ray tube is the first tube available for clinical routine utilizing convective cooling exclusively. It is demonstrated that this cooling principle makes large heat storage capacities of the anode disk obsolete. The unprecedented cooling rate of 4.8 MHU/min eliminates the need for waiting times due to anode cooling in clinical workflow. Moreover, an electronic beam deflection system for focal spot position and size control opens the door to advanced applications. The physical backgrounds are discussed and the technical realization is presented. From this discussion the superior suitability of this tube to withstand g-forces well above 20 g created by fast rotating gantries will become evident. Experience from a large clinical trial is reported and possible ways for future developments are discussed.     

Autosensitization by Sperm in Guinea Pigs

Guinea pigs injected intradermally with homologous sperm or testis in Freund's adjuvant developed the following manifestations of hypersensitivity: (a) histamine release from lung after treatment with antigen in vitro; (b) Schultz-Dale reactions (occasionally); (c) antibodies capable of passive sensitization in vitro (passive sensitization demonstrated by histamine release); (d) antibodies immobilizing sperm in presence of complement; (e) skin reactions with an immediate and a delayed component.

Autologous and homologous guinea-pig sperm or testis were equally active as antigens in producing histamine release from sensitized lung. Boar and rat sperm and guinea-pig kidney and brain were inactive. Although living sperm acted as an effective antigen its activity increased after freezing and thawing, when most of the activity was present in the supernatant. The antigen in sperm is stable at 56° but appreciable inactivation, increasing with time, occurs at 100°.

Attempts to transmit the hypersensitivity by transference of lymph node cells into the skin of normal recipients have been unsuccessful. Some evidence was obtained that testis sensitized cells per se produce local reactions which are greater than those of normal cells.

Fixation of antibody on the acrosomal portions of sperm was demonstrated by means of fluorescein tagged anti-globulin serum. The possibility is discussed that the antigenic activity of sperm may be due to a mucopolysaccharide.

     

The action of soluble antigen—antibody complexes in perfused guinea-pig lung

When soluble antigen—antibody complexes, prepared in antigen excess, were injected into the perfused pulmonary artery of the unsensitized guinea-pig lung, they produced a bronchoconstrictor response which was associated with the appearance of histamine and a slow-reacting substance in the effluent. This activity was inhibited by the presence of normal rabbit serum or rabbit globulin; rabbit albumin and bovine γ-globulin produced no inhibition. Insoluble antigen—antibody complexes prepared at equivalence were at least 125 times less active than soluble complexes prepared in antigen excess. On comparing the activity of different solutions of soluble complex prepared in antigen excess ranging from 2½ to 160 times that required for equivalence, all were found to be equal. The properties of soluble antigen—antibody complexes are consistent with the possibility that circulating antibody may participate in in vivo anaphylaxis, if reached by an amount of antigen greater than that required for equivalence.     

An improved immunoblotting procedure for the detection of antibodies against HIV

Immunoblotting ('Western blotting') is routinely used for detection of antibodies against HIV in the diagnosis of HIV infection. We describe an improved procedure, which does not require virus purification and is easy to control for 'false-positive' results. The technique also does not produce erroneous results due to reactivity of the developing system with residual cellular proteins or viral antigens and does not give high nonspecific background staining. The technique can be applied to the detection of antibodies to HIV in serum, plasma, and blood products.     

Expression of a human cDNA encoding a protein containing GAR synthetase,AIR synthetase,and GAR transformylase corrects the defects in mutant Chinese hamster ovary cells lacking these activities

The isolation of a human cDNA encoding the multifunctional protein containing GAR synthetase, AIR synthetase, and GAR transformylase by functional complementation of purine auxotrophy in yeast has been reported. Chinese hamster ovary (CHO) cell mutant purine auxotrophs deficient in GAR synthetase (Ade^–C) or AIR synthetase plus GAR transformylase (Ade^–G) activities were transfected with this human GART cDNA subcloned into a mammalian expression vector. This restored 49–140% of the activities of GAR synthetase, AIR synthetase, and GAR transformylase in transfected cells when compared to wild-type CHO K1 parental cells. Study of one stably expressing transfectant, AdeC2, revealed that the human GART cDNA was incorporated into the CHO genome. The enzyme activities appear to be associated with an expressed protein of 110 kDa, very similar to that of purified human GART trifunctional enzyme. The Ade^–C mutant shows reduced amounts of GART mRNA compared to CHO K1 and a protein of apparently reduced size, results consistent with the purine requirement and enzyme deficiency observed in the mutant. These experiments provide definitive evidence that the human GART cDNA encodes and can direct the production of active human GART trifunctional protein in mammalian cells. They also provide important evidence that the Ade^–C and Ade^–G mutants of CHO cells are defective in this gene.