Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “quantitative complementation”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,351 records · Page 75Linked to original sources
PubMed2000

Relationship between serum bactericidal activity and serogroup-specific immunoglobulin G concentration for adults, toddlers, and infants immunized with Neisseria meningitidis serogroup C vaccines.

A new meningococcal group C-CRM(197) conjugate vaccine (MnCC; Meningitec) has been evaluated in multiple clinical trials in the United States and most recently has been approved for routine administration in the United Kingdom. Meningococcal serogroup C (MnC)-specific immunoglobulin G (IgG) antibodies in pre- and postimmunization sera obtained from healthy U.S. adults, toddlers, and infants were quantitated by enzyme-linked immunosorbent assay (ELISA) and by an antibody-dependent, complement-mediated serum bactericidal assay (SBA). Serogroup-specific IgG antibody (micrograms per milliliter) in adults immunized either with the quadrivalent polysaccharide (A, C, Y, and W-135) vaccine or with MnCC showed a strong correlation (r = 0.848 and 0.934, respectively) by linear regression analysis with SBA. Sera from infants immunized with the MnCC (n = 30) and an age-matched unimmunized control group (n = 15) were also analyzed. Linear regression analysis of serum bactericidal and IgG ELISA data from sera obtained at 2 months of age (preimmunization) showed no correlation; however, a high degree of correlation was observed at time points after two (r = 0.877) and three (r = 0.951) immunizations, where significant rises in anti-MnC polysaccharide antibodies occurred relative to the age-matched control group. Infants previously primed with 3 doses of MnCC were given a booster dose of conjugate vaccine at 12 to 15 months of age. The correlation coefficient of ELISA to SBA for combined pre- and postbooster data was r = 0.836 (n = 48 pairs). In conclusion, increases in serum bactericidal activity in immunized adult, toddler, and infant populations were found to correlate very well with increases in serogroup-specific IgG concentrations, whereas the correlation between these two assays in nonimmunized 2-month-old infants was poor. Characterizing the relationship between these methods is important for understanding the significance of antigen-specific antibody concentrations relative to vaccine performance and protection from disease.

Adult↗
PubMed1991

Analysis of proteins eluted from hemodialysis membranes.

To further investigate the types of interactions occurring between blood and hemodialysis membranes, proteins were sequentially eluted from used dialysers. Four different membranes (cuprophan, hemophan, cellulose acetate and polyacrylonitrile) were successively treated with a hydrogen bond cleaving agent (10 M urea), an ionic detergent destabilizing the hydrophobic interactions between apolar groups (SDS solution), and a hydroxylamine solution at alkaline pH to release postulated covalently bound C3 fragments. The eluted proteins were analyzed by SDS-PAGE and immunological techniques. Total protein determinations demonstrate different behaviour of the membranes as regards the 'protein cake'. Electrophoretic analysis suggests that qualitative and quantitative differences in the binding of the blood proteins are related to the membrane material. Complement fragment studies indicate that the complement activating potential of the dialysis membrane may not be determined by the availability of potential binding sites for activated C3b. An attempt is made to correlate these results with the biocompatibility concept.

Acrylic Resins↗
PubMed1978

Cytological effects of hormones and plasma on bovine mammary tissue in vitro.

Mammary explants from two heifers pretreated with oestradiol and progesterone were cultured for 96 h with various combinations of hormones and calf plasma to identify the complement causing mammary tissue development in vitro in the cow. Initial tissue histology, determined by quantitative morphological analysis, was maintained by incubation with insulin, cortisol, oestrogen and progesterone; enlarged lumina were observed after treatment with insulin and cortisol. Lactogenesis was induced in vitro by insulin, cortisol and prolactin, enhanced by adding oestrogen and progesterone at the doses used here and further stimulated by the addition of plasma. The most highly developed mammary alveoli were characterized by an increased luminal area with lipid and stainable secretion, epithelia with large lipid droplets in the apical cytoplasm and a limited stromal area. In a second experiment, samples of plasma were collected from two cows, successfully induced to lactate, on days 6, 15, 17, 19 and 21 after treatment with oestradiol and progesterone. Mammary gland explants from five heifers pretreated with oestradiol and progesterone in vivo were cultured with insulin and cortisol plus these plasma samples (30%, v/v) to test for changes in lactogenic activity. All plasma samples were found equally beneficial in promoting tissue differentiation. These experiments show that low concentrations of ovarian steroids synergize with prolactin at the level of the mammary epitherlium and suggest that other plasma components aid the development of bovine mammary epithelium in vitro.

Animals↗
PubMed1995

Electronic infrared thermography as a method of assessing herpes labialis infection.

The purpose of this study was to ascertain the applicability of infrared thermography to study the natural history of herpes labialis lesions. Since thermography is capable of detecting changes not visible to the naked eye, then it may be of value in complementing clinical examination of the various stages of herpes labialis. In addition, thermographic imaging is quantitative and therefore allows for an accurate assessment of temperature changes accompanying the disease process, both within patients and between patients. Ten female patients suffering from herpes labialis were studies (mean age 25 +/- 5 years). In all cases herpes simplex virus Type 1 was isolated by the HEP-2 technique. No treatment was instituted and patients were clinically assessed and thermographically imaged daily from the prodromal phase through to resolution. A marked temperature increase (1 degree C minimum) was observed within hours of the prodromal phase and maintained until day 4. As the lesions progressed to vesicle formation, the central area of the vesicle was noted to be cooler due to the insulating effect of the fluid. Even by day 6 a significant 0.5 degree C temperature increase over background was present at the involved site and this returned to normal within 8 to 10 days. The area of thermographic involvement was three to four times larger than the clinical area of involvement (60-100 mm2 versus 20-25 mm2). To assess reproducibility, we also studied patients through two additional untreated herpes labialis episodes. The prodromal phase was reproducible thermographically and characterized by a temperature increase of 1.42 degrees C +/- 0.2 degrees C. Thermographic imaging may represent a new approach to quantifying disease activity in herpes labialis, particularly in the subclinical prodromal stage.

Adult↗
PubMed1991

Detection of human factor B biosynthesis in culture supernatants and cell lysates by ELISA.

We report here on the development of a simple, sensitive, convenient, and quantitative enzyme-linked immunosorbent assay for human factor B, a protein of the alternative complement pathway, by the sandwich method using goat anti-human factor B antibody. The assay described herein is reproducible and highly specific for human factor B. The assay was used to determine biosynthesis (cell lysates or extracts) and secretion (supernatants) of human factor B using human monocyte cell line U937. Phorbol myristate acetate strongly enhanced (10- to 20-fold) biosynthesis of factor B by U937. The combination of a sensitive enzyme-linked immunosorbent assay and phorbol myristate acetate enabled us to use a microculture system.

Antimetabolites↗
PubMedDate not supplied

[Complex studies of virology, microbiology, biochemistry and epidemiology in the adults of a semi-closed community vaccinated against influenza with the inactivated NIVGRIP vaccine intranasally].

A study was conducted on the specific and non specific immunomodulator effects of the inactivated vaccine NIVGRIP. The results revealed the seroconversion of HAI antibodies against influenza and mumps viruses and the reduction of viral and microbial flora of the pharynx. The kinetics of some proteins specific to the acute stage (siderophiline antitrypsin, microglobulin, complement C1q and C2 factors, C reactive protein and fibronectin) was also investigated and significant quantitative modifications were noticed in vaccinated subjects. The mean illness duration (acute respiratory disease) was three times as short in vaccinated subjects as in controls.

Acute-Phase Proteins↗
PubMed2006

cDNA microarray analysis of non-selected cases of acute myeloid leukemia demonstrates distinct clustering independent of cytogenetic aberrations and consistent with morphological signs of differentiation.

Acute myeloid leukemia (AML) is a heterogeneous disease with respect to biology and clinical course. Until now the basis for prognostic evaluation and therapeutic decision has been the karyotype, genetic FLT3 abnormalities and the initial chemotherapy response. A question that has emerged is if extensive gene expression analysis may supplement or partly replace current diagnostics. In an attempt to address this question, we performed cDNA microarray analysis on peripheral blood samples of 25 patients with newly diagnosed AML with high blast counts. The patients were randomly selected from a large group of consecutive patients. Leave-one-out crossvalidation (LOOCV) showed with high accuracy that gene expression classifiers could predict if leukaemia samples belonged to the FAB AML-M1 or to the FAB AML-M2 groups. An unsupervised two-dimensional hierarchical cluster analysis generated 3 patient subgroups. Except for an accumulation of samples classified as FAB M1 and M2 in cluster 3, there was no evident relationship between the clusters and the FAB classification. Each subgroup displayed clearly distinguished gene expression patterns validated using real-time quantitative PCR analysis. The identification of specific gene expressions that together constitute regulatory modules must complement cluster analyses in order to achieve an accurate basis for prognosis and prediction.

Adult↗
PubMed1977

A comparative study of detection methods for Aleutian disease viral antibody.

Four methods of detecting and quantitating mink antibody against Aleutian disease (AD) virus were compared. Counterelectrophoresis, modified, counterelectrophoresis, immunofluorescence, and complement fixation were performed blindly on 274 serum samples. All four methods were reliably specific for AD antibody. Immunofluorescence was less reproducible than the other systems. Immunofluorescence complement fixation were 4- to 8-fold more sensitive than regular or modified counterelectrophoresis, but were limited by background staining and anti-complementary activity, respectively, when used to detect small amounts of antibody in undiluted sera.

Aleutian Mink Disease↗
PubMedDate not supplied

Extracellular proteins in breast tumor cytosol.

Several proteins have been quantitated in cytosols prepared from benign and malignant tumors of the breast; orosomucoid, albumin, transferrin, complement 4, C-reactive protein alpha 2-macroglobulin and hemoglobin. With the exception of hemoglobin, concentrations of the proteins measured were significantly intercorrelated. Their relative abundance was close to that reported in blood, except for alpha 2-macroglobulin and hemoglobin which were present in lower amounts. From hemoglobin measurements it can be concluded that blood contamination contributed less than 10% to the cytosol proteins measured. When compared to albumin, none of the proteins investigated occurred in concentrations sufficient to indicate local synthesis of a magnitude that would significantly influence tumor environment. From the present data it can be concluded that extracellular proteins constitute about 50% of total cytosol protein. This indicates an exceptional capillary leakage in breast tumors possibly related to abnormal hormonal influences. There were, however, large individual variations and about 10% of the cytosols could be predicted to contain negligible amounts of cell-derived protein. There was a highly significant difference between benign and malignant tumors in their cytosol content of extracellular protein, benign tumors containing nearly twice as much albumin. It is suggested that measurement of an extracellular protein (albumin) should be included in tumor characterization to correct for cellularity and representativity of tumor samples used for steroid receptor determinations and for measurements of other parameters using "cytosol" protein to express specific activity.

Breast Neoplasms↗
PubMed1978

Lymphocyte responsiveness to mitogens and quantitation of T and B lymphocytes in canine malignant lymphoma.

Two canine malignant lymphoma cases were studied, one from the time of detection of enlarged palpable lymph nodes through the terminal stage and another at the terminal stage. Hematologic and histopathologic studies were confirmative of leukemia. The lymphocyte subpopulations, T and B cells, were quantitated as identified by the presence or absence of surface immunoglobulin and erythrocyte-antibody-complement-rosette formation. The average number of B cells in the peripheral blood lymphocytes throughout the study were approximately 80%. The B cells in the lymph node lymphocytes were 82%. There was considerable fluctuation in the number of blood lymphocytes, but the percentage of T and B lymphocytes remained nearly constant. There was marked impairment in the lymphocytic response to mitogens. The results of this study indicate that the canine malignant lymphoma is predominantly a B-lymphocyte type.

Animals↗
PubMed1983

Immunological findings in kala-azar, Iran.

Quantitation of immunoglobulins in patients with systemic leishmaniasis show a rise in IgM and IgG. Complement C3 levels in severely ill patients were very low, whereas generally within normal range in patients with uncomplicated recoveries. The cell mediated immune response of those kala-azar patients examined appeared to be depressed as measured by PHA skin tests. This depression was rapidly reversed following chemotherapy with Glucantim.

Adolescent↗
PubMed1982

Restricted deposition of C3 on M+ group A streptococci: correlation with resistance to phagocytosis.

In this report, the mechanism of resistance to phagocytosis by group A streptococci and the participation of M protein in this process were studied. A quantitative fluorometric immunoassay was used to determine the amount of the opsonic third component of complement, C3, fixed by group A streptococci in the presence and absence of M protein. In the absence of M protein, phagocytosis was found to be dependent on the amount of C3 fixed. However, when M protein was present, the streptococci still bound sufficient C3 to have promoted phagocytosis, yet none was observed. Further investigation using immunofluorescent microscopy demonstrated that the C3 fixed to M+ chains was confined to dense patches, interspaced by areas devoid of detectable C3. This uneven distribution of C3 was dependent on the presence of a trypsin-sensitive structure; most likely the M protein. The significance of this restricted C3 deposition with respect to resistance to phagocytosis by group A streptococci is discussed.

Animals↗
PubMed1994

Characterization and affinity isolation of xenoreactive human natural antibodies.

Natural Abs, which are thought to provide an initial defense against invasive microorganisms, include isohemagglutinins, anti-phosphatidylcholine Abs, and anti-alpha-galactose Abs. We have evaluated the physiologic properties of the fraction of human natural Abs that bind to porcine endothelial cells and that would, as a result, initiate the rejection of a porcine organ transplanted into a human. The concentration of xenoreactive IgM in the serum varied widely in the population (5 to 105 micrograms/ml), but was highly dependent on the concentration of IgM in the serum (r = 0.85). Despite this variation and the potential diversity of epitopes recognized, human xenoreactive natural Abs exhibited surprisingly homogeneous binding characteristics, both in one individual and in the population. The apparent avidity determined by using a direct ELISA yielded a functional dissociation constant of 10(-8) M to 10(-10) M, depending on the temperature used. This high functional Kd apparently results from polyvalent interactions between the IgM and the porcine cell surface. Although the xenoreactive IgMs were absorbed by structurally diverse molecules such as ssDNA and thyroglobulin, about 80% of the xenoreactive Abs were specific for the terminal alpha-galactose determinant. A method was developed for affinity isolation of xenoreactive natural Abs by using a thermal extraction procedure. The method quantitatively accounts for all xenoreactive IgM, yielding functional IgM as evidenced by Ag binding and complement activation. Given the overlapping specificity of xenoreactive Abs in the population and the homogeneity of the functional Kd, the natural humoral immunologic barrier to xenotransplantation may be far less formidable than previously thought.

Animals↗
PubMed1993

Measurement of total hepatic low density lipoprotein receptor levels in the hamster.

The ability to measure the total concentration of low density lipoprotein (LDL) receptors in hepatic tissues is of crucial importance to understanding changes in hepatic cholesterol metabolism. Such measurements can be made in conjunction with estimates of LDL receptor transcriptional activity, cell surface LDL receptor number, and rates of hepatic LDL uptake to evaluate the mechanisms controlling cellular LDL receptor expression. Current methods for assessing hepatic LDL receptor levels use microsomes as a source of LDL receptor, and thus rely on consistent contamination of the microsomal preparation with LDL receptor-containing plasma membranes, endocytic vesicles, and/or secretory vesicles. Because this contamination is variable, and may vary with alterations in either the distribution of LDL receptors among the various cellular membrane fractions or in the composition of the intracellular membranes, measurement of LDL receptor concentration in microsomal fractions may not accurately reflect the total compliment of LDL receptors within the cell. We have developed the methodology for isolating the full complement of hepatic LDL receptor containing membranes by discontinuous sucrose density gradient centrifugation, and for quantitating LDL receptor concentration using a Western immunoblotting procedure that uses an anti-C-terminal LDL receptor peptide polyclonal antiserum and assesses the intensity of color formation by reflectance densitometry. Using this methodology, we observed a 126 kDa immunoreactive band for the bovine adrenal cortex LDL receptor that also exhibited LDL binding activity as visualized by biotinylated LDL-ligand blotting, and a doublet of 140 kDa for the hamster liver LDL receptor. These bands were not observed when ligand blotting was conducted in the presence of either 10 mM EDTA or a 5-fold excess of unlabeled LDL, or when immunoblotting was conducted using either preimmune serum or antiserum that had been preabsorbed with LDL receptor peptide. The intensity of color formation was a linear function of the amount of membrane extract separated by electrophoresis. Intra-assay variation averaged 7%, and inter-animal variation averaged 20%. Cholestyramine, tiqueside, CP-88488, 17 alpha-ethinyl estradiol, mevinolin, and the combination of cholestyramine plus mevinolin, pharmacological interventions known to increase LDL receptor activity in experimental animals, produced the predicted increases in hamster total hepatic LDL receptor concentration that were highly correlated with concomitant increases in HMG-CoA reductase activity and reductions in serum cholesterol.(ABSTRACT TRUNCATED AT 400 WORDS)

Amino Acid Sequence↗
PubMed1983

Induction of zymosan-air-pouch inflammation in rats and its characterization with reference to the effects of anticomplementary and anti-inflammatory agents.

Induction of an experimental inflammation of the air-pouch type with the aid of zymosan (known to activate the alternative pathway of the complement system) was carried out in an attempt to induce a reproducible inflammatory model suitable for quantitative studies. Rats were injected subcutaneously with 8 ml of air on the dorsal surface to make an air-pouch, followed 24h later by 4 ml of 1.6% (w/v) zymosan suspension. This induced inflammatory responses. Treatment with zymosan suspension provoked exudation of fluid, accumulation of polymorphnuclear leukocytes (PMN) in the pouch and the development of granulation tissue as a wall of the pouch. Approximately half of the PMN in the pouch formed a characteristic layer of aggregated cells sticking onto the inner surface of the pouch wall. They were counted after being completely disaggregated by means of incubation with trypsin. In preliminary experiments with potential anti-inflammatory drugs, local application of a novel anti-complementary agent, K-76COONa, inhibited leukocyte accumulation in the pouch, whereas the potent anti-inflammatory agent, dexamethasone, was ineffective. By contrast, exudation of the pouch fluid was effectively inhibited by dexamethasone but not by K-76COONa.

Animals↗
PubMed1976

Genetic studies of coliphage P1. III. Extended genetic map.

An extensive genetic map of coliphage P1 has been constructed for 113 amber mutants, using primarily a modification of the conventional complementation spot test. These spot tests failed to classify the mutants into cistrons, but when they were quantitated they permitted assignment of the mutants into 10 linkage clusters. Furthermore, a linear order could be deduced for most of the mutants within each cluster. This strongly suggested that recombination was the predominant event generating plaques and that, for the practical purpose of rapid genetic mapping, such spot tests could be considered as a series of two-factor crosses. Six of the 10 linkage clusters correlated with the P1 genetic map established by Scott (1968). The locations of the remaining four clusters were determined by three-factor crosses and by prophage deletion mapping. The nonrandom occurrence of termini for 14 deletion prophages, which we established previously (Walker and Walker, 1975), and the coincidence of these termini with five out of ten regions demarcating the linkage clusters are discussed. Complementation tests in liquid frequently gave ambiguous results. Therefore, cistron designations were not assigned.

Chromosome Mapping↗
PubMed1995

Complement-independent binding of microorganisms to primate erythrocytes in vitro by cross-linked monoclonal antibodies via complement receptor 1.

Under certain circumstances, soluble antigens, particulate antigens, and/or microorganisms have been shown to bind to primate erythrocytes via complement receptor 1 (CR1) in the presence of specific antibodies and complement. This immune adherence reaction, specific for CR1, can lead to neutralization of antigens in the circulation and their subsequent clearance from the blood. The present experiments utilized cross-linked monoclonal antibody complexes (heteropolymers) with specificity for both CR1 and either 35S-labeled herpes simplex virus capsid or Haemophilus influenzae as prototype viral and bacterial particulate antigens, respectively. In each case, the respective specific heteropolymers facilitated binding of the target antigens (> or = 70 to 90%) in vitro to erythrocytes in the absence of complement. Several experimental protocols were employed to demonstrate that heteropolymers mediate specific, rapid (> or = 30 s), and quantitative binding of prototypical particulate pathogens to human and monkey erythrocytes but not to sheep erythrocytes, which lack CR1. These results extend the potential use of the erythrocyte-heteropolymer system to the neutralization and clearance of particulate viral and bacterial pathogens from the blood.

Animals↗
PubMed1999

Image and visual analyses of G-banding patterns of camomile chromosomes.

Karyotypes of three cultivars of Matricaria chamomilla L. were studied using the developed G-like banding technique. The G-banding patterns of chromosomes were reproducible and chromosome-specific. Visual analysis allowed us to reveal from 5 to 10 G-positive bands and/or blocks of adjacent bands on individual chromosomes. In accordance with the G-banding patterns and morphology of chromosomes, all 9 homologous pairs were identified. The G-banding patterns of chromosomes in karyotypes of different Matricaria chamomilla L. cultivars were similar, thus indicating their species-specific character. The description of G-banding patterns of camomile chromosomes was given in accordance with the revealed G-band polymorphism, and the ideogram of M(ch) genome chromosomes was created. Image analysis of G-banding patterns of camomile chromosomes revealed up to 18 G-positive bands per chromosome with different staining intensity. As a result, the quantitative M(ch) genome ideogram reflecting structural peculiarities of chromosomes (band size, position, and staining intensity) was constructed. Comparison of the results of visual and image analyses of G-banding patterns of camomile chromosomes showed that they complemented each other. The first approach allowed us to determine the main peculiarities of G-banding patterns and the second one - to study the quantitative and qualitative characteristics of the G-banded chromosome structure. Our results demonstrate the prospects of the G-like banding technique together with the image chromosome analysis in studying small-chromosome plant species.

Chamomile↗