Cell Culture Engineering IX.
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Journal Article↗
Biomedical subjects
K Konstantinov
Publications and source records attributed to K Konstantinov.
In-situ fabrication of nanostructured cobalt oxide powders by spray pyrolysis technique.
Nano-crystalline Co3O4 and CoO powders have been prepared by a spray pyrolysis approach. The effects of the reaction temperature and initial salts on the crystallinity and phase composition have been studied. Based on the TEM and XRD results, the crystal sizes were in the range of 1-10 nm. SEM and TEM observations also reveal that the nano-powders easily create micron-scale spherical agglomerates. The Co3O4 powders obtained by spraying nitrate solution at 500 degrees C show high specific surface area, which according to the BET method is 82.37 m2/g. The time/temperature phase diagram of cobalt oxides developed from XRD and DTA/TGA analyses shows the existence of a CoO phase at low and high temperature ranges when some specific preparation conditions are applied.
Biocompatible Materials↗
Fabrication and properties of spray-dried nanofeatured spherical Ni(OH)2 materials.
Spherical agglomerates of nanostructured beta-phase Ni(OH)2 with the general formula Ni1-xCox(OH)2 (x = 0, 0.1, 0.3) for use as cathode materials were produced by a modified method including coprecipitation of Ni or Ni composite hydroxide and further spray drying of the precipitated and washed slurry. This process leads to the formation of spherical agglomerate particles with a narrow Gaussian-type distribution range. The method permits faster and cheaper production of cathode materials with a higher specific surface area and similar or better capacity and cycle life compared with the materials prepared via conventional technology.
Aerosols↗
High frequency of autoantibodies to insoluble cellular antigens in patients with chronic fatigue syndrome.
OBJECTIVE: To elucidate the humoral immune response in patients with chronic fatigue syndrome (CFS), by identification and characterization of autoantibodies. METHODS: Initial immunofluorescence histochemistry studies of sera using human HEp-2 cell substrate were followed by antibody class subtyping and colocalization studies with reference antibodies. Association of CFS autoantigens with insoluble cellular components was determined by in situ extraction of soluble components and subsequent immunofluorescence histochemistry studies on the extracted cell substrate. RESULTS: Of 60 CFS patients, 41 (68%) were positive for antinuclear antibodies. Localization of nuclear staining was found at the nuclear envelope (52%), in reticulated speckles (25%), in nucleoli (13%), and in dense fine speckles (5%). Twenty-eight CFS sera (47%) also had antibodies to cytoplasmic antigens. The major cytoplasmic staining pattern was of the intermediate filament type (35%). The observed nuclear envelope pattern of staining co-localized with lamina-associated polypeptide 2 (an integral nuclear membrane protein), the reticulated speckle pattern co-localized with non-small nuclear RNP splicing factor SC-35, and the intermediate filament pattern co-localized with vimentin. The intermediate filament antigen was shown to be vimentin in immunoblotting experiments using recombinant human vimentin, and one of the nuclear envelope antigens was shown previously to be lamin B1. Fifty of the 60 CFS patients (83%) had antibodies to one or another of these antigens, all of which are relatively insoluble cellular antigens, whereas a control group of patients without chronic fatigue had a significantly lower frequency of such antibodies (17%). CONCLUSION: The high frequency of autoantibodies to insoluble cellular antigens in CFS represents a unique feature which might help to distinguish CFS from other rheumatic autoimmune diseases.
Antibodies, Monoclonal↗
Autoantibodies to nuclear envelope antigens in chronic fatigue syndrome.
We have identified and partially characterized the autoantibodies in sera of 60 patients with chronic fatigue syndrome. Approximately 52% of the sera were found to react with nuclear envelope antigens. The combination of nuclear rim staining observed in immunofluorescence microscopy and immunoblot analysis of highly purified nuclear envelope proteins provided initial characterization of these autoantibodies. Further characterization showed that some sera immunoprecipitated the in vitro transcription and translation product of a human cDNA clone encoding the nuclear envelope protein lamin B1. The autoantibodies were of the IgG isotype. The occurrence of autoantibodies to a conserved intracellular protein like lamin B1 provides new laboratory evidence for an autoimmune component in chronic fatigue syndrome.
Adult↗
Knowledge-based systems, artificial neural networks and pattern recognition: applications to biotechnological processes.
Recent years have witnessed the increasing application of artificial intelligence techniques, specifically, knowledge-based systems, artificial neural networks, and pattern recognition, to biotechnological processes. Although progress has been made in simple control applications, more work is needed to establish the advantages of these techniques for industrial process control, for diagnosis/monitoring, and to upgrade the information content of historical data.
Biotechnology↗
Integral membrane proteins associated with the nuclear lamina are novel autoimmune antigens of the nuclear envelope.
We have analyzed sera from 55 patients, most with rheumatic diseases, that all react with the nuclear envelope of human cells in immunofluorescence microscopy. The molecular targets of these autoantibodies were characterized by immunoblot analysis of fractions derived from rat liver nuclear envelopes. While numerous sera were found to react with previously characterized autoimmune antigens of the nuclear envelope including nuclear lamins and the pore complex glycoprotein gp210, a substantial number of the sera were found to recognize relatively minor integral membrane proteins of the nuclear envelope associated with the nuclear lamina (LAP 1A and LAP 2), which have not been previously identified as autoantigens. Autoantibodies to LAP 1A and LAP 2 are present in 9 and 29% of the patient sera, respectively. Only autoantibodies to lamins A/C were encountered more frequently (in 31% of the sera) than autoantibodies to LAP 2, suggesting that LAP 2 may be among one of the most prominent autoantigens of the nuclear envelope in rheumatic disease patients. Since recent studies have suggested that LAP 1A and LAP 2 may be involved in attaching lamins and chromosomes to the nuclear envelope, these findings could promoted understanding of nuclear envelope functions as well as autoimmunity.
Autoantibodies↗
Real-time biomass-concentration monitoring in animal-cell cultures.
The accurate, on-line measurement of cell concentration in animal-cell cultures is an on-going problem in bioprocess engineering, and the development of new monitoring techniques is an area of intensive and fruitful research. This article summarizes the recent advances, trends and problems in this field and focuses, in particular, on optical sensors, including the latest laser and infrared probes. Alternative methods, such as multiple-extinction fluorimetry, real-time imaging and particle-size analysis, are also discussed. Although many of these techniques are still at an experimental stage, we believe that some of them have been developed sufficiently that we advocate their routine use in bioprocess monitoring and control.
Animals↗
[Serology in patients with scleroderma].
In order to evaluate the practical clinical value of centromere, Scl-70, and nucleolar antibodies as demonstrated routinely by the Autoimmune Department of the Serum Institute of Copenhagen, 1293 sera from 497 patients with scleroderma (SSc) and other connective tissue diseases were tested for the three antibodies and for other nuclear antibodies. The three antibodies were found in 32, 15 and 15%, respectively, of sera from patients with SSc. Since more than one of the three antibodies was rarely demonstrated in any one serum, one of them was found in two thirds of sera from patients with SSc. The specificity of the three antibodies for SSc was 95% or more. Centromere antibody was found most frequently in patients with limited SSc. Scl-70 antibody was found almost exclusively in sera from patients with extensive SSc (involving the skin of the trunk). In such sera, centromere antibody was found in only 21%. Scl-70 antibody was overrepresented and centromere antibody was underrepresented in sera from patients with pulmonary involvement, the converse being true for sera from patients with calcinosis, esophageal involvement and telangiectasia.
Antibody Specificity↗
Clinical manifestations in patients with autoantibodies specific for nuclear lamin proteins.
IgG antibodies to nuclear lamin proteins have been found in serum samples from 31 patients using immunofluorescence on HEp-2 cells, Western blotting, and enzyme-linked immunosorbent assay, performed against a nuclear lamina preparation from Ehrlich ascites tumor cells. Antilamin antibodies were most prevalent among patients with nonerosive, seronegative polyarthritis, or patients showing serum antiphospholipid reactivity as well. It is possible that anti-lamin antibodies may thus be a marker for a subgroup of polyarthritis patients who have a different prognosis from that of those with seropositive rheumatoid arthritis. The mechanism for the combined occurrence of anti-lamin and antiphospholipid autoantibodies is obscure. Future studies will answer whether these two antibodies represent a distinct antibody profile in patients with antiphospholipid antibody syndrome.
Adolescent↗
Lipoid proteinosis.
Lipoid proteinosis (Urbach-Wiethe disease) is a rare, recessively inherited disorder that is characterized by the deposition of hyaline-like material in the skin, oral cavity, and other tissues. It usually appears in infancy with hoarseness. We report a case of lipoid proteinosis in a 10-year-old boy that demonstrates the characteristic clinical, histologic, and ultramicroscopic features of this disease.
Child↗
[New technology in maize breeding].
Results obtained by several approaches in the application of Biotechnology in maize breeding are reviewed. RFLP technology in the determination of genetic variation; gene transfer by the use of different methods of gene delivery and the determination of gene integration. Three technologies for foreign gene introduction have been applied; injection of plasmid pRT100 neo into archesporial tissue before micro and macro sporogenesis, slightly modified pollen-tube pathway technology and dry seed incubation in plasmid DNA solution. NPTII gene integration was followed by dot-blot and Southern blot analysis of plant DNA of both T1 and T2 plants. Gene expression was analysed by neomycin phosphotransferase activity. Transformed plants contained the selective NPTII gene sequence in an active form. Bacterial gene integration induced several heritable changes of plant phenotype. As an important change, alteration of the flowering time has been used as a criterion for selection and plant propagation to keep transformed progeny. Besides plant genome transformation, endogenous bacteria living in different maize tissue were found. As a perspective approach for biotechnology application in maize breeding biological vaccine construction has been selected. Therefore, antagonistic effect of gram positive bacterial strains to several pathogenic fungi was investigated. Results obtained after in vivo experiments are discussed.
Breeding↗
Interferon response to dipyridamole in lupus erythematosus patients.
Studies in patients with autoimmune disorders strongly support a role for interferon (IFN) in the disease process. In the present study we investigated the in vivo production of alpha-IFN in lupus erythematosus patients after stimulation with dipyridamole, recently characterized as an alpha-IFN inducer in mice and humans. Levels of IFN were measured in serum samples from 22 patients with systemic lupus erythematosus (SLE) and 12 patients with discoid lupus erythematosus (DLE) before and 24 h after dipyridamole administration. IFN activity was assayed on human and bovine cells in parallel. Initial serum concentrations of alpha-IFN in SLE patients were markedly elevated. The percentage of DLE positive responders to dipyridamole induction was about twice as high as that found for SLE. Studies of factors responsible for IFN production in lupus erythematosus might result in better understanding of the relationship between DLE and SLE.
Dipyridamole↗
[The chologon-sorbitol functional test under ultrasonic control in pathology of the gallbladder and biliary tract].
The degree of the filling up and the dilation of the gall bladder, its functional state as well as the passibility of d. cysticus are evaluated by ultrasound examination and computer determination of the surface and dimensions of the gall bladder. 546 patients, 20-78 years of age (484 women and 62 men) were examined by a pharmacodynamic functional test with chologon (acidum dehydrocholicum) in a dose of 10 mg/kg body mass and sorbitol (in 116 patients) in a dose of 20 g in 100 ml of water. The functional test is easily performed in the course of the ultrasound examination and side effects were registered. The test allows the assessment of the functional state of the gall bladder, the passibility of d. cysticus, the degree and mechanism of the filling up of the gall bladder and the bile ducts with bile. The better filling up of the gall bladder with bile after application of chologon (by passable d. cysticus) ensures better conditions for detecting microgallstones in the gall bladder as well as of diseases linked with its wall--cholesterosis, cancer and polypi of the bladder, etc.
Adult↗
Bullous lichen planus and lichen planus pemphigoides.
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Adult↗
[Dysplastic nevus syndrome].
We report on 3 families showing increased occurrence of malignant melanoma (MM). As the patients suffering from MM also revealed great numbers of nevi, we suspected dysplastic naevus syndrome.
Adult↗
Antibodies to histones and disease activity in systemic lupus erythematosus: a comparative study with an enzyme-linked immunosorbent assay and immunoblotting.
Enzyme-linked immunosorbent assay (ELISA) and immunoblotting were used to define comparatively the frequency of antibodies to total histones and different histone fractions - H1, H2A, H2B, H3, and H4 - in 16 patients with idiopathic systemic lupus erythematosus. H1 and H2B showed the most prominent antigenic properties; H3's were weaker, while antibodies to H2A and H4 were rarely detected and only with the more sensitive ELISA on microtiter plates. Detailed specification was carried out of the antigenic determinant on fragments obtained by specific cleavage of purified H1 at phenylalanine-106. Antibodies were detected against both the NH2 and COOH terminal halves of the molecule. The presence of antihistone antibodies was not associated with any particular clinical symptoms, but an obvious link with disease activity has been proved.
Antigen-Antibody Complex↗
Some changes in verbal reactions, attentions, intellectual work capacity and memory in elderly and old people physically trained in the course of two years.
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Aged↗