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M Klinger

Publications and source records attributed to M Klinger.

At least 73 records · Page 4Linked to original sources
PubMed1994

Post-embedding immunocytochemistry for adhesive proteins and clathrin in LR White- and LR Gold-embedded human platelets.

Two hydrophilic acrylic resins, LR White and LR Gold, were tested for their suitability for post-embedding immunocytochemistry on human platelets. Both resins gave satisfying results with regard to ultrastructural preservation and retention of antigenicity for von Willebrand factor, fibrinogen, fibronectin and clathrin. Embedding in LR White and polymerization at 50 degrees C without accelerator proved to be the best method because it provided clear negative membrane contrast, good immunocytochemical localization of antigens and the entire procedure required a comparatively short time. Label for von Willebrand factor was found in typically eccentric location in alpha-granules, but also in the form of small caps directly outside the granule membranes, beneath the outer plasma membrane and in the cytoplasm. With the exception of the eccentric location within granules, labelling for fibrinogen and fibronectin revealed very similar results. Label for clathrin appeared in the form of small gold clusters attached to alpha-granules, in the cytoplasm and beneath membranes of the open canalicular system. Together with the appearance of coated vesicles attached to granules and to the membranes of the open canalicular system in araldite-embedded material, these results further strengthen the concept that adhesive proteins are taken up from the plasma and stored in granules. Moreover, the persistence of the clathrin coat on vesicles attached to storage granules may also indicate that receptors for adhesive proteins are recycled.

Acrylic Resins↗
PubMed1994

[Monthly intravenous cyclophosphamide in the treatment of lupus nephritis].

21 patients with severe active lupus nephritis (LN) were treated with intravenous cyclophosphamide monthly doses 0.75 g/m2. The effects were compared with the results obtained in 22 patients by the oral prednisone administration in the dose 1 mg/kg/day. Both groups were not significantly different as regards the initial intensity of the LN symptoms. Complete or partial remission occurred in 17 patients (80.9%) receiving intravenous cyclophosphamide. End-stage renal failure in 2 patients and moderate renal insufficiency in other 2 patients from that group. In the prednisone treated group complete or partial remission was observed in 13 subjects (59.1%). The significant deterioration of the renal function occurred in 9 patients, in 6 into the phase of a moderate renal insufficiency and in 3 patients to the end-stage kidney failure. Additionally, the significant increase of the total serum complement activity and of the plasma platelets count was observed in the cyclophosphamide group, whereas those indicators did not improve in the patients receiving prednisone. The of intravenous pulse cyclophosphamide exhibits an advantage in the treatment of severe proliferative LN.

Adolescent↗
PubMed1994

Dysmorphic red cell formation in glomerulonephritis. 2. In vitro generation of dysmorphic erythrocytes.

In the present study influences leading to in vitro formation of dysmorphic erythrocytes were studied. Fresh and surface altered erythrocytes pretreated with several proteases were passed through different solutions representing distinct nephronís fluids. After passage of intact erythrocytes only 12-15% dysmorphic cells were observed. In case of protease treated cells the number of dysmorphic cells rose to 35-80%. The hemoglobin content was decreased. PAGE and electron microscopical findings demonstrated substantial losses of transmembrane and membrane skeleton proteins. It is assumed that surface protein degradation, loss of membrane skeleton proteins and hemolysis seem to be closely associated with dysmorphic malformation of urinary erythrocytes characteristical for glomerulonephritis.

Anisotropy↗
PubMed1994

[Effect of leukocyte contamination on storage of platelet concentrates from buffy coats].

We examined the effect of white cell contamination on thrombocytes prepared from pooled buffy coats over a storage period of 8 days. Using this novel technique, a leukocyte depletion filter can be easily integrated during PC preparation. In a paired study (n = 14) eight ABO-identical BC were pooled in a 2-liter PVC bag within 8 h after whole-blood donation, thoroughly mixed and divided into two identical fractions. After soft-spin centrifugation the platelet-rich plasma (PRP) was transferred either (fraction A) using a leukocyte filter (PL 50-HF, Pall) or (fraction B) directly into the storage bag (Pl-732, Baxter), and stored under routine conditions. On days 1, 3, 5, and 8, aliquots of PC were withdrawn for determination of cell count and different biochemical parameters and for morphometric analyses of platelet ultrastructure by electron microscopy. Results showed a lower thrombocyte yield and white cell count (p < 0.01) in fraction A (268 x 10(9) vs. 240 x 10(9); 51.1 x 10(6) vs. 0.04 x 10(6)), whereas no differences between the preparations could be detected by analysis of pH, pCO2, bicarbonate, and in LDH release over the storage period of 8 days. These results were supported in the study on the ultrastructural level where a good morphological integrity of the platelets was observed during the whole storage period in both fractions. In conclusion, storage lesions on platelets due to leukocyte effects are unlikely to occur in PC with white cell counts lower than 10(8)/l.

Blood Platelets↗
PubMed1993

Immunohistochemical visualization of the enteric nervous system using antibodies against protein gene product (PGP) 9.5.

Both the investigation of the enteric nervous system and the diagnosis of its pathological changes require reliable staining methods. In order to assess the potential of protein gene product (PGP) 9.5 as a marker for the enteric nervous system, we examined its immunoreaction in whole-mount preparations of the guinea pig and porcine small intestine, using a rabbit polyclonal antiserum. The immunohistochemical technique reveals the fundamental architectural features of the ganglionic and aganglionic plexuses. Furthermore, it enables a reproducible and differentiated visualization of the enteric nerve cells to be made, so that the various nerve cell types can be morphologically identified.

Animals↗
PubMed1992

Interactions between osteoclastic cells and biodegradable polymers in vitro.

The use of implants to stabilize fractured diaphyseal bone, to handle difficult bone damage and to perform augmentation or replacement procedures in bone has become a common method in bone surgery. In most cases metal implants were used. Biodegradability of implant materials offers new perspectives. Restoration of the physiological status in the implant site becomes possible. Allergic reaction and second operations to remove the implants can be avoided and transitional aid in wound healing by the use of biomaterials can be achieved. An in-vitro system was established to investigate the interactions between osteoclasts and biomaterials, since it is the osteoclasts which are potentially able to resorb or degrade implants. The cell's resorption capabilities as well as its morphological behavior were documented. Two biodegradable and four nonbiodegradable materials were tested. The non-degradable materials provoked specific cell behaviour patterns but were not resorbed. Fibrin tissue adhesive sealant, however, displayed resorption lacunae mediated by osteoclasts, whereas polydioxanone (PDS) showed no resorption sites but normal cellular morphology when compared to the standard control (cells on hydrophilic coated teflon dishes). Both materials appeared to be well accepted by osteoclasts. This test system was established for the valuation of biodegradable implant materials and can be used to characterize new materials concerning their resorbability and biocompatibility without superposition by other cell systems.

Aluminum Oxide↗
PubMed1992

Modified cerium-based and Gomori-based cerium methods for light microscopic phosphatase histochemistry: the cerium-perhydroxide-diaminobenzidine-nickel (Ce-H2O2-DAB-Ni and Ce/Ce-H2O2-DAB-Ni) two-step procedures.

Some modified cerium-based and Gomori-based cerium methods for the demonstration of phosphatase activity in cryostat sections were described. Dextrane as stabilizing agent was added to the incubation media for ATPase, 5'-Nase, and TPPase. The oxidation of the CeIII-phosphate primary reaction product in a separate step by H2O2 before the DAB incubation yielded an increase of the intensity of the DAB-based visualization reaction (Ce-H2O2-DAB-Ni two step method). The sensitivity of the histochemical enzyme reaction was remarkably increased if CeIII-ions were employed as amplifying agent (Ce/Ce-H2O2-DAB-Ni two-step method). A new suitable DAB medium consisting of 0.015% DAB, 2.0% Ni-sulphate, 15% methanol, and 0.005% H2O2 in 0.1 mol/l acetate buffer, pH = 5.2, was used. The disadvantage of diffuse background staining has been overcome by addition of 15% methanol to the DAB solution. Electrovalently bound CeIII (cerophilia) was removed by treatment of the incubated sections with CeIII-citrate (CeIII-complexation). In addition, a novel membrane floating incubation for sections is proposed. At present, the modified procedures are some of the most sensitive modes for the demonstration of phosphatases and improve the earlier described cerium-DAB one-step technique (Halbhuber et al. 1988b).

Animals↗
PubMed1991

Improved light microscopic demonstration of D-amino acid oxidase activity in cryotome sections using cerium ions as capturing and amplifying agent--the Ce/Ce-H2O2-DAB procedure.

The light microscopical demonstration of D-amino acid oxidase (AAOX) activity with cerium (Ce III) as the capturing agent was improved. The incubation medium was stabilized by the employment of triethanolamine and detrane complexed cerium. A considerable increase in intensity of the reaction was accomplished by treatment of the AAOX-incubated sections with Ce III which reacted with the primary reaction product Ce IV-perhydroxide to form Ce IV-hydroxide. In this way the primary reaction product was reduced and enlarged concomitantly. The Ce IV-hydroxide was converted into Ce IV-perhydroxide by H2O2, which was visualized by blue-black stained Ni-DAB complexes. Thus, Ce III is used as capturing agent as well as amplifier (Ce/Ce-H2O2-DAB method). The primary reaction product Ce III-phosphate formed by coreacting phosphatases was selectively extracted by citrate containing glycine-NaOH buffer while Ce IV-perhydroxide remained in the sections. In model experiments it was proven that the perhydroxide groups in the Ce IV-perhydroxide compound initiate predominantly the DAB polymerization while the contribution of Ce III and Ce IV is small.

3,3'-Diaminobenzidine↗
PubMed1991

[Activity of erythrocyte complement receptors class 1 in various kidney diseases].

UNLABELLED: The activity of the erythrocyte complement receptors type 1 (CR1) was measured in four groups: a control group--42 healthy persons, 18 patients with lupus nephritis (morphologic types: membranous, membranoproliferative, and proliferative), 16 patients with primary idiopathic membranous glomerulonephritis (GN), 20 patients with primary idiopathic membranoproliferative GN, and 23 chronic haemodialysis patients, in 20 of them the cause of the end-stage renal failure was primary idiopathic GN. The erythrocyte CR1 activity was determined by the immune adherence test. In the groups of the lupus nephritis and of the end-stage renal failure was observed a significant drop in erythrocyte CR1 activity. On the contrary the patients with primary idiopathic membranous and membranoproliferative GN exhibited a significantly greater erythrocyte CR1 activity than the normals. CONCLUSIONS: 1. The genetic predisposition to primary idiopathic GN is not reflected on the level of the erythrocyte CR1 system, what is distinct from the situation occurred in lupus nephritis, despite similarities in their immunopathogenesis. 2. The development of the end-stage renal failure in the course of primary idiopathic GN shows a inhibitory effect on erythrocyte CR1 activity.

Adolescent↗
PubMed1990

Radiolocalization of human prostate tumor in a mouse subrenal capsule model by monoclonal antibody TURP-27.

The subrenal capsule assay was used to determine if 125I-labeled anti-prostate monoclonal antibody TURP-27 could target human prostate tumor fragments implanted under the renal capsule of normal immunocompetent C57 BL/6 mice. Maximal binding and optimal tumor to non-tumor tissue ratios occurred within 24-48 hours postadministration of 125I-TURP-27. No significant localization was observed in mice bearing TURP-27 antigen-negative human colon tumor tissue implants or with an isotype-matched control monoclonal antibody. These preclinical data suggest that TURP-27 may have clinical application for imaging metastatic prostate tumors and further application in immunoconjugate and/or radiotherapy of prostate cancer.

Animals↗
PubMed1990

Resorption of fibrin tissue adhesive sealant by isolated osteoclasts in culture.

The tissue tolerance of fibrin tissue adhesive sealants has been investigated. These materials are increasingly being used to close wounds and to stabilize spongy bone transplants. An in vitro model consisting of isolated osteoclasts in primary cell culture was used. The 2 commercially available tissue adhesive sealant protein solutions differ substantially with regard to the spreading and resorption capacity of the cultivated osteoclasts.

Animals↗
PubMed1990

Effect of parathyroid hormone on human T cell activation.

Lymphocytes have receptors for PTH and patients with chronic renal failure have high blood levels of PTH and impaired lymphocyte function. It is possible, therefore, that PTH affects lymphocyte function. We studied the interaction between PTH and proliferation of human lymphocytes in vitro and examined potential mechanisms for such an interaction. 1-84 PTH stimulated in a dose dependent manner PHA-induced proliferation of T cells but had no effect on PWM-induced proliferation. The hormone did not alter CD4/CD8 ratio. Inactivation of PTH abolished its stimulatory effect. PTH augmented IL-2 production by PHA-activated T cells but did not increase expression of IL-2R. 1-34 PTH also stimulated PHA-induced T cell proliferation. TPA augmented PHA-induced T cell proliferation but the addition of PTH to the culture stimulated by PHA and TPA did not augment further the proliferation of T cells. Staurosporin reversed the stimulation by PTH of the PHA-induced lymphocyte proliferation. Both 1-34 and 1-84 PTH stimulated cyclic AMP production by lymphocytes. Forskolin did not affect PHA-induced T cell proliferation although it stimulated cyclic AMP generation. The results show that: 1) PTH acts on T cells; 2) acute exposure to PTH augments PHA-induced T cell proliferation and IL-2 production; 3) this action of PTH is related to its biological activity and is most likely due to the ability of PTH to enhance entry of calcium into cells and/or stimulation of protein kinase C but is independent of cyclic AMP generation.

Adult↗