Biomedical subjects
Publications and source records attributed to I Baumgartner.
Intermittent venous claudication develops mostly in young patients after iliac vein thrombosis and subsides promptly in the recumbent position. Plethysmographic assessment of calf volume during treadmill work permits objective diagnosis of the phenomenon remaining frequently unrecognized.
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Inspection, auscultation and doppler-sonographic examination of the jugular veins may give a clue for diagnosis of cardiac diseases. Angiological diseases include isolated thrombosis of the jugular vein and congenital ectasia. The neck veins are enlarged with thrombosis of the major upper extremity veins, if the orifice of the subclavian vein is also occluded and the normal outflow of the jugular vein is impeded. Thrombosis of the superior vena cava, compression of the mediastinal trunks by tumors, fibrosis or pericardial alterations causes dilatation of neck veins on both sides, best seen in the jugular veins.
A method for HLA-ABC and HLA-DR typing of human donor eyes using pigmented retinal epithelial and uveal cells cultured in the presence of human recombinant gamma-interferon is described.
Acanthamoeba keratitis has become a difficult diagnostic and management problem in contact lens patients over the last few years. A young female contact lens wearer presented with a long history of painful central corneal ulcer. The suspected diagnosis of Acanthamoeba keratitis could only be confirmed by histology and electron microscopy following penetrating keratoplasty. Special stains of scrapings and culture of material on special media failed to establish the diagnosis. This rare (or underdiagnosed?) infection must be considered in the differential diagnosis of keratitis following contact lens wear.
Although the design of PMMA intraocular lenses has reached a stage of sophistication at which further modifications are unlikely to result in any major improvements in implant surgery, new materials with possibly improved mechanical and biologic properties should be evaluated carefully. The hydrogel lens (containing 38% poly-HEMA) is a soft, flexible, hydrophilic "single-piece" posterior chamber lens which could help to minimize intraoperative and postoperative IOL trauma. Fifty hydrogel intraocular lenses were implanted during a ten-month period using a standard extracapsular cataract extraction technique. Implantation was considered easy in most cases. As regards biocompatibility, stability of lens position, and visual acuity, the postoperative results are promising. In the follow-up period reported on, no central opacification of the posterior lens capsule was observed.
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A method for HLA-ABC typing using pigmented retinal epithelial and uveal cells of the donor eye is described and the possible implications for corneal grafting are mentioned.
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Human alveolar macrophages (AM phi) from thirteen patients, who were suffering from various lung diseases were harvested by bronchoalveolar lavage. Peripheral blood monocytes from eight healthy donors were isolated by Ficoll-Hypaque gradient centrifugation and adherence to plastic surface. To detect the VEP13 antigen (CD16) on these cells, a rosette assay employing ox erythrocytes coated by the CrCl3 method with purified VEP13 monoclonal antibody (Eo-VEP13) was used. A mean of 31.3% of freshly isolated AM phi and 3.9% of blood monocytes formed Eo-VEP13 rosettes. Monocytes cultured for 3 or 6 days in the presence of a supernatant from mouse L929 cells, which had been shown previously to improve long-term viability of human monocytes in culture, showed 12.5% and 25.3% Eo-VEP13 rosettes, respectively. No significant increase in VEP13 antigen expression was noted by culturing monocytes without L929 cell supernatant. The factor in L929 supernatant that induces VEP13 antigen expression has not been identified. Tunicamycin at 10 micrograms/ml inhibited significantly VEP13 antigen expression on monocytes. In contrast, IgG rosette formation was not reduced by tunicamycin. Our data show that subpopulations of native human AM phi and peripheral blood monocytes cultured in presence of a supernatant of L929 fibroblasts containing mainly murine CSF may express the CD16 antigen, which is normally found on large granular lymphocytes (LGL). Suppression by tunicamycin indicates that Fc receptor glycosylation takes place during a later differentiation step of mononuclear phagocytes.
Due to the absence of vessels and lymph drainage, human cornea is the tissue grafted with the greatest success. From an immunological point of view, this advantage is lost when the recipient cornea has pronounced vascularization and is sensitized. In such cases, which have a poor prognosis, the postoperative success rate drops to below 50% due to graft rejection. The origin and point of attack of the immune reaction to the graft are the MHC antigens of the donor cornea, which occur on almost all nucleated cells. Since they are capable of triggering a T cell activation in the recipient they set immunological effector mechanisms in motion which lead to elimination of the cells carrying the alloantigen. Corresponding to the MHC antigen expression (both Class I as well as Class II) on all cells in all layers of the cornea, rejection reactions of all the various cell types (epithelial, stromal, endothelial) are also seen. By using histocompatible donor corneas it is possible to influence the afferent arm of the immune response preoperatively and thus to diminish its effect on the postoperative course.
The positive influence of HLA-compatible donor material on successful transplantation was proven especially for prognostically unfavourable cases. Nevertheless it is not clear whether varying importance should be attached to the antigen incompatibilities at the HLA-A and HLA-B locus. 62 keratoplasty patients, 37 of whom had primarily poor prognoses and 25 patients with low risk of transplant rejection were prospectively given transplants in which more than two certain incompatibilities at the HLA-A and HLA-B locus had been ruled out. The number of Ag incompatibilities (separately according to locus) was related retrospectively to postoperative progress. An irreversible transplant failure had occurred in 6 patients (16%) four months after surgery in the high-risk group, whereas 31 transplants (84%) remained clear. The course of healing was without complications within the first four months in all patients with favourable starting position. The influence of the HLA disparities on transplantation success was examined by means of the chi-square test. Taking the Ag incompatibilities of both loci in combination into account showed an only marginally significant (p = 0.1) influence on the survival rate of the transplant. Here HLA-A incompatibilities appear to have only secondary significance, whereas incompatibilities at the HLA-B locus correlated inversely (p = 0.02) with the success of transplantation.
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We analysed needles of Pinus radiata along three transects through the South Island of New Zealand for chlorinated hydrocarbons ( alpha- and gamma-HCH, HCB and PCB) and PAH (fluoranthene, 3,4-benzopyrene, benzo(ghi)perylene and indenopyrene). At rural sites we also collected samples of moss (Wijkia extenuata) and lichens (Usnea sp.) in order to compare the pollutant concentrations within these plants. A principal component analysis confirmed findings from moss and snow studies in Europe that the PAH concentrations vary regionally in the same way. The pattern of the principal component loadings of the chlorinated hydrocarbons reflects their heterogeneous immission and their different chemodynamics. The regional pattern indicates an increase of gamma-HCH from remote areas to those used intensively for agriculture and gardening, followed by a decrease towards the inner city of Christchurch. In contrast, PCB and PAH show their highest levels of contamination in the city. The regional distribution of PAH in Christchurch correlates well with traffic density, and particularly with the pattern of smoke from domestic fires. Our study demonstrates that needles of P. radiata can be better monitors of atmospheric pollution in New Zealand than mosses or lichens.
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