Immobilization of ligands with organic sulfonyl chlorides.
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Alcohol Dehydrogenase↗
Biomedical subjects
K Nilsson
Publications and source records attributed to K Nilsson.
Blood-glucose concentrations during anaesthesia in children. Effects of starvation and perioperative fluid therapy.
Blood glucose concentration, pH and standard bicarbonate concentration were measured in 70 anaesthetized children aged between 2 weeks and 22 months before and following surgery. The duration of starvation varied between 4 and 14 h (mean 5.8 h). The lowest blood-glucose concentration before operation was 2.9 mmol litre-1 (53 mg dl-1). Preoperative blood-glucose concentrations were not influenced by the age or weight of the child, or the duration of starvation. During operation the children received either a balanced Ringer acetate solution (group A) or a Ringer glucose solution containing 2.5% glucose (group B). In these patients the preoperative starvation did not result in hypoglycaemia and, during surgery, increases in blood-glucose concentration were found even in those children receiving a glucose-free fluid regimen.
Anesthesia, General↗
Further studies of plutonium and americium at Thule, Greenland.
Eleven years after the accidental loss of nuclear weapons in 1968, the fourth scientific expedition to Thule occurred. The estimated inventory of 1 TBq 239,240Pu in the marine sediments was unchanged when compared with the estimate based on the 1974 data. Plutonium from the accident had moved further away from the impact point and at some locations the vertical distribution indicated a downward displacement of Pu in the sediment column since 1974. Seawater and seaplants showed no evidence of the presence of Pu from sources other than fallout; but Pu in benthos varied nearly proportionally with the levels in sediments. From the measurements of 239,240Pu in the Macoma community since 1970, the transfer factor to this community was estimated at 0.01 Bq a per Bq released to the sediments. The inventory of 241Am was 0.1 TBq. The vertical distribution of Am in sediments did not differ from that of Pu, but in benthos 241Am/239,240Pu were two times higher than in sediments. Seaplants showed the same value of Am/Pu as seawater. There was no indication of any biomagnification of Pu or Am through the marine food chains at Thule.
Americium↗
Acute effects of maternal smoking on fetal heart beat intervals.
The purpose of this study was to analyse the acute effects of maternal cigarette smoking on the fetal heart beat intervals and their variability during the last trimester of a normal gestation. The fetal heart beat intervals were monitored continuously by abdominal electrocardiography for 60 min before and 60 min after smoking in 10 pregnant women. The mean intervals, their long-term variability (SD) and short-term variability (standard deviation of interval differences (SDID], calculated for 30-sec periods, showed a steady state before smoking. During the control period, the mean beat interval was negatively correlated with daily cigarette consumption and the short-term variability was positively correlated with the maternal plasma nicotine level. After smoking, the mean beat interval and the short-term variability decreased transiently, the values of both these parameters being positively correlated with the maternal nicotine values before smoking. The acute response of fetal heart beat intervals and their variability to one cigarette is distinct but transient, and the results suggest that the effects are modified by the chronic smoking habits of the women.
Adult↗
Neuron-specific enolase as a marker for neuroblastoma and small-cell carcinoma of the lung.
The use of neuron-specific enolase (NSE, E.C. 4.2.1.11) as a clinical marker for neuroblastoma and small-cell carcinoma of lung (SCCL) is presented. Both tumors have a high content of NSE as demonstrated enzymatically or by immunocytochemistry. Other retroperitoneal tumors in children and other lung tumors had insignificant NSE concentrations. NSE can thus be used in the differential diagnosis of neuroblastoma and SCCL. 73% of patients with SCCL had elevated serum NSE levels. The corresponding figure for patients with other types of lung cancer was 3%. There was a good correlation between serum NSE levels and the clinical course of patients with SCCL.
Adult↗
Expression of intermediate filaments in established human lung cancer cell lines. An indicator of differentiation and derivation.
A panel of established human pulmonary cancer cell lines, representing the major histopathologic groups according to the World Health Organization (WHO) classification (WHO 1, squamous cell carcinoma; WHO 2, small cell carcinoma; WHO 3, adenocarcinoma; WHO 4, large cell carcinoma) were examined for their expression of various types of intermediate filaments in order to determine their phenotypic differences and to attempt to disclose their histogenetic origin. The cells were investigated with antibodies specific for cytokeratin, vimentin, and neurofilament polypeptides with both immunofluorescence microscopy and immunoblotting techniques. Squamous cell carcinoma and adenocarcinomas expressed cytokeratin in accordance with the epithelial nature of these tumors but not neurofilament polypeptides. Small cell carcinomas, on the other hand, were positive for neurofilaments but negative for keratin. In contrast to small cell carcinoma, adenocarcinoma, and squamous cell carcinoma, one cell line derived from large cell carcinoma appeared to express both neurofilaments and keratin. All cell lines studied also contained variable amounts of vimentin, a phenotypic characteristic obtained by many cells under in vitro conditions. The results demonstrate, in accordance with our earlier observations in vivo, a distinctly divergent expression of intermediate filament proteins in different types of lung cancers. The persistence of this phenotypic heterogeneity in vitro consolidates the use of cell cultures as useful models to study the biologic behavior and interrelationships of lung cancers. Based on the present studies, and taking into account the occurrence of mixed forms of lung cancers, we present a hypothetical scheme of the histogenetic derivation of different types of lung cancers.
Adenocarcinoma↗
Phorbol ester treated chronic B lymphocytic leukaemia cells induce autologous T cell proliferation without generation of cytotoxic T cells.
The ability of the tumour promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) to modify the stimulatory capacity of leukaemic B cells in autologous mixed leucocyte reactions (AMLR) was studied. T lymphocytes from patients with chronic lymphocytic leukaemia (CLL) did not proliferate when stimulated with untreated autologous non-T cells. In contrast, vigorous 3H-thymidine incorporation was seen in six of eight cases when CLL stimulator cells were pre-incubated for 3 days with TPA. No cytotoxic T cells against TPA treated or untreated autologous target cells were generated in such AMLR. These results indicate that enhancement of AMLR stimulatory capacity may be among the characteristic features of TPA driven in vitro differentiation of CLL cells.
B-Lymphocytes↗
[Importance of suture technics in obstetric patients' pain experience with healing of oblique incision].
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Episiotomy↗
Toward the use of monoclonal antibodies in the analysis of tumor progression and cellular heterogeneity of human breast cancer.
Most, if not all human tumors have a clonal derivation. However, during the expansion of a tumor cell clone secondary genetic changes are continuously generated (tumor progression) leading to phenotypic heterogeneity. This cellular heterogeneity appears to be the basis for the evolution of a metastatic behaviour and resistance to chemo- and radiotherapy. Using conventional histopathology only a very limited information is obtained concerning this heterogeneity but in the case of human breast cancer additional knowledge is provided by analyses of cellular DNA content and estrogen and progesteron receptors. During the last few years a very impressing progress has been made in attempts to raise monoclonal antibodies against breast cancer using the hybridoma technique. A number of diagnostically and perhaps therapeutically useful antibodies are already available. It is therefore anticipated that within the next few years a panel of anti-breast cancer antibodies will be made available which will be able to define cellular heterogeneity and identify prognostically important tumor cell markers.
Animals↗
High-performance liquid affinity chromatography on silica-bound alcohol dehydrogenase.
Horse liver alcohol dehydrogenase was immobilized on glycerylpropyl-silica (10 micron, 1000-A pores) activated with 2,2,2-trifluoroethanesulfonyl chloride (tresyl chloride). The coupling and activity yield was almost 100%. The coenzyme-binding sites were equivalent and virtually unaffected by the immobilization process, as judged from Scatchard plots and active-site titrations. The silica-bound enzyme, packed in steel columns, was integrated with HPLC equipment and then successfully used for chromatography of adenine nucleosides, adenine nucleotides, and triazine dyes. Dissociation constants were calculated from chromatographic data and found to correspond well with literature values. The dissociation constants for a number of nucleotide derivatives with potential application in affinity chromatography were also determined. The spaces were found to affect the binding strength of the nucleotides in a qualitatively predictable way. Theoretical plate heights were calculated and found to be in the range 0.01 to 0.1 cm. Attempts to correlate peak widths with the rate constants for the binary complexes involved were only partially successful.
Alcohol Dehydrogenase↗
Formation and growth of multicellular spheroids of human origin.
Different types of human cells which normally grow as monolayers or suspension cultures were tested for their capacity to form and grow as spheroids. Sixteen out of the 27 tested tumour cell lines formed spheroids. Nearly all of these spheroids also grew. With only two exceptions the doubling times were longer when the tumour cells grew as spheroids than when they grew in conventional mass culture. Eleven out of 13 tested human non-tumour cells formed small spheroids but of these only the spheroids of lymphoid origin could grow. These lymphoid cells grew faster when aggregated to spheroids than when in single-cell suspension culture. None of the other non-tumour cells, which normally grew as monolayers, could grow as spheroids. The normally monolayer-cultured tumour cells formed symmetrical spheroids with smooth surfaces while the normally suspension-cultured cells formed irregular spheroids with rough surfaces. All large spheroids had a necrotic centre surrounded by a shell of viable cells. The thickness of the viable cell layer varied depending on cell type. The shape and organization of cells within the spheroids also varied largely. The results show that many types of human cells can be cultured as spheroids and that a wide spectrum of morphological appearances and growth rates can be obtained.
Cell Aggregation↗
Entrapment of animal cells for production of monoclonal antibodies and other biomolecules.
Animal cell technology is attracting considerable interest because of the capacity of animal cell cultures to synthesize or transform complex compounds such as virus vaccines, immunochemicals, hormones or enzymes. For the growth of surface-dependent cells, microcarrier technology is gaining importance. Here, we have attempted to immobilize surface-independent cells, normally grown in suspension, by entrapping them in polymer microbeads. Such entrapment should give increased stability to the normally fragile animal cells, allow for high cell densities to be achieved within the beads and make such preparations suitable for continuous operation. At the same time, the need for separation of the desired product from the cells is obviated. With the model systems studied, we showed that hybridoma, as well as other cell lines entrapped in agarose microbeads, remained viable. Both immunoglobulins and lymphokines were exported through the microbeads into the medium for 1-3 weeks, at levels corresponding well to those produced with free cells.
Animals↗
[Sacral anesthesia, an easy and safe method for postoperative analgesia in children].
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Adolescent↗
Iron metabolism of established human hematopoietic cell lines in vitro.
Three malignant hematopoietic cell lines were used in studies on cellular iron metabolism. Our results show that iron-carrying transferrin became bound to specific dimeric cell surface receptors. Iron accumulated within the cell with time, whereas intact transferrin was released back to the medium. Chloroquine and NH4Cl, known as pH-raising agents in vesicles of the lysosomal system, inhibited iron accumulation and transferrin binding in a dose-dependent manner. This suggests that the acid pH in endosomes leads to the cleavage of the iron-transferrin bonds. Transferrin degradation was not found, which leads us to suggest a process of 'acid flushing' for the dissociation of iron from transferrin without the involvement of endosome-lysosome fusion. Taken together, the data agree with the concept of receptor-mediated endocytosis, as described for many macromolecules. Iron was stored in ferritin in the cell types tested. Only a minor part (less than 15%) of the iron was bound in hemoglobin in the K-562 cell line. The relationship between iron stores and exogenously added iron in heme synthesis was investigated using a double labelling (55Fe/59Fe) technique. The results showed that exogenous iron was preferentially used before the iron stored in ferritin. The results are discussed in relation to various hypotheses on cellular iron uptake and transport.
Ammonium Chloride↗
Monocytic origin of the human hematopoietic cell line U-937 and its convertibility to macrophages evidenced by isoenzyme mapping.
U-937 represents a well established permanent human hematopoietic cell line. Electron microscopical and enzyme cytochemical studies as well as the analysis of surface glycoproteins have provided ample evidence for the monocytic origin of U-937. Upon stimulation with the tumour promotor 12-O-tetradecanoylphorbol-13-acetate (TPA), U-937 cells evolve into macrophage-like cells with phagocytic capacities. Since human blood monocytes (BM) are characterized by five acid esterase (AcE; EC 3.1.1.6) isoenzymes which are cell-specific in terms of isoelectric points (pI) and antigenicity, attempts were made in the present study to identify identical isoenzyme patterns in non- and TPA-stimulated U-937 cells. BM, cultured BM, non- and TPA-stimulated U-937 cells, as well as samples of resident human peritoneal macrophages (PM) as clearly-defined functional derivatives of BM, were subjected to isoenzyme analysis using isoelectric focusing (IEF). The five monocyte specific isoenzymes of AcE were identified in both populations of U-937. TPA-stimulated samples showed two additional bands, identical to those appearing in cultured BM after 4 days of glass-adherence and characteristic of resident human PM. Antisera raised against AcE of BM immunoprecipitated the two additional isoenzymes of TPA-stimulated U-937. It is concluded (1) the isoenzyme mapping of AcE documents the monocytic origin of U-937. (2) TPA-stimulation caricatures transformation of BM into resident tissue macrophages as far as pure morphology and AcE isoenzyme patterns are concerned. Thus, AcE isoenzyme mapping is apt for establishing reproducible and standardized criteria of different activation/differentiation states within the monocyte-macrophage lineage.
Animals↗
Column separation of monocytes by adherence to gelatin beads.
This investigation was performed to study whether the efficient binding of collagen to monocytes in the presence of fibronectin and heparin may be used for separation of monocytes from human peripheral blood. It was shown that monocytes adhere selectively to gelatin bead columns in the presence of fresh plasma and heparin. Mononuclear blood cells are rapidly depleted of monocytes by passage through a 5-10 ml column at a flow rate of 1.5-2.0 ml per min. Adhering lymphocytes are more loosely attached and may be detached by stirring and washing, while the monocytes can be eluted by 50 mM EDTA. This separation technique is suitable for combination with various other methods since it is rapid, allows convenient handling of large numbers and yields cells with very high viability. Although most B lymphocytes pass through the column without attaching, there is some enrichment of B cells and non-T, non-B cells among the adherent lymphocytes.
Animals↗
Natural killer cells and their targets: impact of differentiation on target cell susceptibility.
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Animals↗
Kinetics and concentration effects of TPA-induced differentiation of cultured human neuroblastoma cells.
SH-SY5Y human neuroblastoma cells differentiate morphologically and biochemically in the presence of 12-0-tetradecanoylphorbol-13-acetate (TPA). The degree of differentiation, as demonstrated by the appearance of cell surface projections, growth inhibition and increase in noradrenalin concentration, was dependent on the TPA concentration and had an optimum at 1.6 X 10(-8) M of TPA. At that concentration neuron specific enolase (NSE) increased to a maximum level after 10 days of culture with no further changes in the NSE level during additional culture for 10 days. In contrast, the noradrenalin concentration reached a maximum after 4 days of TPA treatment and decreased during longer exposures to TPA. Based on the facts that the phorbolester induced differentiation shows stereo specificity and was optimal at the same concentration range as common polypeptide hormones, a putative TPA-hormone receptor interaction is discussed. An opposite effect of TPA on the SH-SY5Y cells, antagonizing the differentiation effect, is further suggested to explain the decrease in differentiation observed at TPA concentrations higher than 1.6 X 10(-8) M.
Caenorhabditis elegans Proteins↗