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Biomedical subjects

B Schiller

Publications and source records attributed to B Schiller.

At least 37 records · Page 2Linked to original sources
PubMed1991

Monocyte phenotype and interleukin-1 production in patients undergoing haemodialysis.

The expression of MHC class II (HLA-DR) and complement receptor (CR1) surface molecules on CD 14+ monocytes were compared with the production of the monokine interleukin-1 beta (IL-1 beta) in patients with endstage renal disease undergoing maintenance haemodialysis (HD) with hollow fibre dialyzers containing cellulose (CE, n = 8) and polysulfone (PS, n = 7) membranes. Monocyte staining was performed in blood samples obtained at the beginning and after 3 h of HD. Analysis of surface marker expression was done by immunofluorescence staining and flow cytometry analysis. Specific fluorescence intensity for both CR1 and class II (HLA-DR) antigens was increased in patients treated with CE membranes at the beginning of a dialysis treatment when compared to healthy control values. Interestingly, after 3 h on dialysis a further increase was noted for CR1 complement receptor expression whereas the increased HLA-DR expression was no longer detectable. In contrast, specific fluorescence intensity for both antigens was not significantly different from controls, either before or after dialysis, in patients treated with PS. The capacity of peripheral blood mononuclear cells to produce IL-1 beta spontaneously in vitro in the two patient groups was found to parallel results on phenotypic expression of surface molecules. The present study demonstrates that functional signs of monocyte activation, as evidenced by an augmented IL-1 beta production, in some patients on long-term HD correlate with an increased expression of two functionally important monocyte surface marker molecules.

Adult↗
PubMed1990

Differential activation of monocytes in haemodialysis patients exposed to different types of membranes.

Peripheral blood mononuclear cells (PBMC) from haemodialysis patients treated with different types of membranes were isolated, incubated in vitro, and extracellular and cell-associated interleukin I (IL-1) assayed by radioimmunological methods. Extracellular IL-1 was low and not different from controls, regardless of the dialyser used. In contrast, cell-associated IL-1 was increased in patients treated with dialysers containing low-flux Cuprophan (CU, n = 5) and polyacrylonitrile sheet membrane (AN69, n = 5). Patients treated with dialysers containing high-flux polysulphone (PS, n = 7), and polymethylmethacrylate (PMMA, n = 8), exhibited no increase in cell-associated IL-1 under these conditions. To elucidate the mechanism of the activation, aqueous extracts of dialysers containing CU, PS, and AN69 were tested for their ability to induce IL-1 generation in PBMC from healthy donors. Extracts from unrinsed CU-containing dialysers caused significant IL-1 synthesis and release, whereas incubation with extracts from dialysers containing PS and AN69 sheet membranes did not. Hence, although both CU and AN69 sheet-type dialysers result in activation of blood monocytes the mechanism of action appears to be different. We speculate that functional signs of PBMC activation as evidenced by increased spontaneous IL-1 production observed in some patients on long-term haemodialysis may result from extractable dialyser membrane material while in other instances direct cell membrane interactions or endotoxin transfer from the dialysate may be relevant.

Adult↗
PubMed1990

First glance on the three-dimensional structure of the photosynthetic reaction center from a herbicide-resistant Rhodopseudomonas viridis mutant.

A first model of the three-dimensional structure of the photosynthetic reaction center of the mutant T1 (SerL223----Ala, ArgL217----His) from Rhodopseudomonas viridis, resistant toward the triazine herbicide terbutryn (2-methylthio-4-ethylamino-6-t-butylamino-s-triazine), has been developed from X-ray data measured to a resolution of 2.5 A. The secondary quinone, QB, which in T1 binds better than in the wild type, is present in the crystals. Both substituted residues are clearly visible in the difference fourier map. The replacement of these two residues in the QB site causes only minor changes in the overall structure of the protein.

Amino Acid Sequence↗
PubMed1989

Wheat dwarf virus, a geminivirus of graminaceous plants needs splicing for replication.

By analysing mRNAs with the polymerase chain reaction (PCR) and by studying in vitro generated mutants we have identified an intron in the genome of wheat dwarf virus (WDV), a geminivirus of cereals. Polypeptides whose expression is essential for the replication of the viral DNA have been defined. They are encoded by two distinct overlapping open reading frames (ORFs). The joining of these two ORFs by deletion of the intron as well as the introduction of a frameshift mutation within the intron do not prevent replication of the viral genome in suspension culture cells. In contrast to WDV, the geminiviruses of dicotyledonous plants possess a single continuous ORF, highly homologous to the two individual ones of WDV. We propose that mRNA splicing is a common feature of all geminiviruses of the Gramineae and might contribute to their host class specificity. The existence of a functional intron is a novel finding for the plant viruses.

Amino Acid Sequence↗
PubMed1989

Activation of mononuclear cells by aqueous extracts from hollow-fibre haemodialysers.

Monocytes from patients treated by long-term haemodialysis with cellulosic membranes can show functional signs of activation depending on the dialyser module. To elucidate the mechanism of this phenomenon, aqueous extracts of various hollow-fibre dialysers were tested for their ability to induce in-vitro interleukin-1 generation in peripheral blood mononuclear cells from healthy donors. Extracts were prepared by passing 0.5 litres of sterile endotoxin-free water from the dialysate to the blood compartment of the dialyser. Different dialysers containing cellulosic membranes, i.e. cuprophan, and hemophan, were studied. Extracts were dried by lyophilisation and resuspended in cell culture medium before incubation with peripheral blood mononuclear cells for 18 hours at 37 degrees C in a 5% CO2 atmosphere. Interleukin-1 was assayed by biological or radioimmunological methods. Extracts from steam-autoclaved, dry-stored, or gamma-sterilised, wet-stored cuprophan and hemophan modules resulted in interleukin-1 activity that did not differ from negative controls. By contrast, extracts from cuprophan caused significant interleukin-1 production when prepared from ethylene oxide-sterilised, dry-stored dialysers. This monokine-inducing activity could not be neutralised by the addition of polymyxin B and was heat unstable, indicating that the cell-activating stimulus was not endotoxin. Extensive rinsing of the module with water before extract preparation totally mitigated the in-vitro production of interleukin-1. Our results suggest that the extract-induced activation of peripheral blood mononuclear cells found with some dialysers containing membranes of cellulosic origin cannot be exclusively related to the membrane polymer, but depends on a number of other parameters such as sterilisation and storage mode of a given membrane.

Adjuvants, Immunologic↗
PubMed1988

Intrauterine cranial gunshot wound in a 32-week fetus.

Intrauterine cranial gunshot wounds are rare and usually associated with a fatal outcome for the fetus. We present a case where preterm delivery, neonatal intensive care, and later removal of the bullet resulted in a normal child without any untoward sequelae.

Adult↗
PubMed1985

Planning of Ir-192 seed implants for boost irradiation to the breast.

The conservative management of early stage breast cancer with tumor excision and irradiation of the breast is becoming increasingly accepted as an alternative to modified radical mastectomy. The radiotherapy typically consists of 45 to 50 Gy delivered with external beam irradiation, followed by boost irradiation of 15 to 20 Gy to the tumor bed using electron beams or interstitial implantation. Pathological evaluation of the excised tumor, clinical assessment, and mammography are used to determine the tissue volume potentially containing a residual tumor burden and therefore requiring boost irradiation. In this paper we describe planning and implantation procedures for Quimby-type breast implants using Ir-192 seeds encapsulated in nylon tubing. This system deviates in several important respects from the requirements of the standard brachytherapy systems. For double-plane implants, optimized values of the interplanar spacing are given for a range of implant sizes, along with the corresponding target dose rates for 1.0 mCi seeds. We also describe a modification of the angiocatheter implantation technique, which allows the radioactive sources to be secured in place by a magnetic cap and washer, thus greatly facilitating the removal of the sources at the end of treatment.

Brachytherapy↗
PubMed1985

[Polish preparations for preventing and treating infections caused by Pseudomonas aeruginosa].

Three preparations, viz. sheep serum for local application ("Sanoserum"), anti-Pseudomonas sheep immunoglobulin for passive immunization ("Immunoglobulin Pseudomonas") and Pseudomonas vaccine for active immunization ("Pseudovac"), have been obtained at the Central Laboratory of Sera and Vaccines in Warsaw, Poland. The laboratory study and clinical trial of these preparations have been carried out. The preparations have proved to be effective as supplement to the conventional methods for the early diagnosis and treatment of P. aeruginosa infection in burn patients.

Adult↗
PubMed1984

[Immunotyping of freshly isolated strains of Pseudomonas aeruginosa].

During 1972-1982 the bacteriological study of 1391 patients with thermal burns was carried out. As the result of clinico-bacteriological studies, the occurrence of P. aeruginosa was found to increase from 39.3% to 70.5% during this period. The immunotyping of P. aeruginosa cultures isolated in 3 burn-treatment centers showed that strains belonging to immunotypes 2, 3, 7 and 3/7 were most frequently isolated from burn wounds. These strains were found to be the cause of hospital infections in burn-treatment hospitals. In connection with the data thus obtained immunological preparations intended for the prophylaxis and treatment of P. aeruginosa infection should include P. aeruginosa strains, immunotypes 2, 3, 7 and 3/7.

Bacterial Vaccines↗
PubMed1984

Anti-Pseudomonas immunoglobulin. IV. Combined anti-Pseudomonas immunoglobulin and Pseudomonas vaccine immunotherapy of burned patients--clinical investigations.

Sheep anti-Pseudomonas immunoglobulin and Pseudomonas vaccine were used for combined immunotherapy in 55 severely burned patients. The results of clinical investigations show that active and passive immunization in the early state of thermal injury increases the anti-Pseudomonas agglutinin titer, diminish the threat of Pseudomonas sepsis and death and significantly accelerate the recovery.

Bacterial Vaccines↗
PubMed1983

Anti-Pseudomonas immunoglobulin. III. Preliminary clinical evaluation.

Preliminary clinical evaluation of sheep anti-Pseudomonas immunoglobulin was performed on 20 burn injured patients. The patients were divided into two comparable groups of ten persons. One group was treated with the immunoglobulin shortly after thermal injury (in about two days). The patients of the second group received this preparation in about 18 days post thermal injury. It was concluded that the sheep anti-Pseudomonas immunoglobulin is well tolerated by patients. The results of clinical observations show that, in respect to incidence of sepsis and survival, only early administration of immunoglobulin can prevent further development of infection caused by Pseudomonas aeruginosa.

Adolescent↗
PubMed1981

Immunological study of antisera to to artificial O-antigen of Pseudomonas aeruginosa.

O-sera were obtained by immunizing rabbits with artificial antigens: polysaccharide extracted from the lipopolysaccharide of P. aeruginosa (strain No. 868; 03a, 3d, 3e), or the high-molecular-weight or low-molecular-weight fraction of this polysaccharide, complexed with a natural protein (human IgG or rabbit globulin). The antisera to these antigenic complexes were highly O-specific. Antisera to the complexes of polysaccharide-protein and high-molecular-weight fraction-protein were more active in the passive haemagglutination reaction, slide agglutination test and immunodiffusion test in agar gel than was antiserum to the low-molecular-weight fraction-protein complex. The artificial antigens prepared and employed in the study are apt to be used for the preparation of monospecific immune sera.

Agglutination Tests↗
PubMed1981

Anti-Pseudomonas immunoglobulin I. Immunization of sheep.

The production of sheep Pseudomonas immune serum is described. The animals were immunized with Pseudomonas vaccine prepared from strains of Pseudomonas aeruginosa belonging to seven immunotypes of Fisher's schema. Immune sera obtained from hyperimmunized sheep are characterized by a high level of stabel antibodies with a good protective activity for mice against infection with Pseudomonas aeruginosa. It has been demonstrated that sheep may be used for a long time as a source of immune serum.

Animals↗
PubMed1981

Anti-pseudomonas immunoglobulin. II. Preparation of purified sheep immunoglobulins.

Several methods of fractionation of sheep anti-sera against Pseudomonas aeruginosa were applied for the preparation of immunoglobulins. The methods involving salting out with ammonium sulfate or purification by means of caprylic acid were shown to be most suitable for isolation of immunoglobulins under manufacturing conditions. The preparations obtained by these methods agglutinated Pseudomonas aeruginosa, suspension in vitro and protected mice against lethal infection with this microorganism.

Animals↗