Filters
Results 1 - 10 of 1800
Results 1 - 10 of 1800.
Search took: 0.022 seconds
Sort by: date | relevance |
AbstractAbstract
[en] The immune response during infectious diseases leads to a rise in antibody titre to the various different antigenic determinants of the causative organism. The response is further complicated by the fact that it is relatively unusual for one individual to respond to all antigenic components of an organism. Demonstration of the specific immune response of an infected host by serological tests is often hampered by the broad cross-reactivity between several bacterial antigens. The authors report on a serodiagnostic application of murine monoclonal antibodies (MAB), specific for a human pathogen, M. tuberculosis by a technique which is applicable in principle to the serodiagnosis of many other infectious diseases. The serum diagnostic test is based on the competitive inhibition by human sera of the binding of 125I-labelled murine monoclonal antibodies to M. tuberculosis-coated polyvinyl plates. Five monoclonal antibodies binding to distinct antigenic determinants of the organism were used as structural probes which conferred their stringent combining site specificities to the polyclonal mixture of antibodies from patients' sera. When compared with healthy controls, increased titres of inhibitory antibodies were found in about 70% of patients with active tuberculosis. The diagnostic value of the individual monoclonal antibodies as well as the benefit from the use of multiple specificity probes has been qualified
Primary Subject
Record Type
Journal Article
Journal
Federation Proceedings. Federation of American Societies for Experimental Biology; ISSN 0014-9446;
; CODEN FEPRA; p. 93

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] Cadmium can replace zinc and magnesium in alkaline phosphatase from Escherichia coli, which permits the characterization of the catalytically important metal-binding sites by 113Cd NMR. At pH 6.5, in the absence of phosphate, two equivalents of cadmium are bound in identical sites (A), one in each monomer. Either raising the pH or phosphorylation of Cd2AP (AP is apoalkaline phosphatase) results in migration of Cd(II) from the site A in one monomer to the opposite monomer to occupy a second site (B) adjacent to the A site in the first monomer, a site stabilized by phosphorylation or high pH. At pH 6.5 in the presence of phosphate, the 113Cd NMR spectrum of Cd6AP consists of three narrow resonances from three pairs of fully occupied sites, A, B, and C. The resonances at 153 and 70 ppm represent two metal sites (A and B) 3.9 angstrom apart at each active center and adjacent to the serine phosphorylated during turnover. At this pH the enzyme exists almost exclusively as the covalent phosphoseryl form E-P with a 31P resonance at approx. 9 ppm. As the pH is raised a 31P signal from the noncovalent E.P complex appears at approx. 13ppm. This is reflected in the 113Cd spectrum by a split of both the A- and B-site resonances into pairs, a set at 137 and 65 ppm for E.P, and 153 and 70 ppm for the E-P species. 113Cd-O-31P coupling of 30 Hz on the 31P resonance of E.P shows the noncovalently bound phosphate to be coordinated to one but not both metal ions at each active site
Primary Subject
Record Type
Journal Article
Journal
Federation Proceedings. Federation of American Societies for Experimental Biology; ISSN 0014-9446;
; v. 41(13); p. 2966-2973

Country of publication
ALKALINE EARTH METALS, BACTERIA, BETA DECAY RADIOISOTOPES, BETA-MINUS DECAY RADIOISOTOPES, CADMIUM ISOTOPES, CHARGED PARTICLES, CHEMICAL REACTIONS, DAYS LIVING RADIOISOTOPES, ELEMENTS, ENZYMES, ESTERASES, EVEN-ODD NUCLEI, HYDROLASES, INTERMEDIATE MASS NUCLEI, IONS, ISOMERIC TRANSITION ISOTOPES, ISOTOPE APPLICATIONS, ISOTOPES, LIGHT NUCLEI, MAGNETIC RESONANCE, MICROORGANISMS, NUCLEI, ODD-EVEN NUCLEI, ORGANIC COMPOUNDS, PHOSPHATASES, PHOSPHORUS ISOTOPES, RADIOISOTOPES, RESONANCE, SPECTRA, STABLE ISOTOPES, YEARS LIVING RADIOISOTOPES
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] Conflicting evidence exists as to whether the gluconeogenetic process is active in the late gestation fetal lamb. In vitro evidence based on measurements of enzyme activity and substrate flux into glucose indicates that the capacity for gluconeogenesis exists in fetal liver. The in vivo conversion of [14C]lactate and [14C]alanine into glucose in the lamb fetus has been demonstrated. Lactate and alanine account for 49 and 2.3% of the fetal glucose pool, respectively. Although gluconeogenesis can occur in the fetal lamb, alterations in net rates of umbilical uptake of glucose or lactate, fetal blood glucose concentrations, fetal or maternal glucose replacement rates, or maternal nutrition may alter the observed rates of fetal gluconeogenesis
Primary Subject
Source
64th Annual Meeting of the Federation of American Societies for Experimental Biology; Anaheim, CA, USA; 15 Apr 1980
Record Type
Journal Article
Literature Type
Conference
Journal
Federation Proceedings. Federation of American Societies for Experimental Biology; ISSN 0014-9446;
; v. 41(1); p. 316-319

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] Nuclear magnetic resonance (NMR) of metalloproteins is briefly discussed, and a summary of the properties of several NMR active nuclei is given. In addition, the use of these NMR properties in solving biochemical problems is presented
Primary Subject
Record Type
Journal Article
Journal
Federation Proceedings. Federation of American Societies for Experimental Biology; ISSN 0014-9446;
; v. 41(13); p. 2959-2960

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] 113Cd NMR has been used to determine the structures of the multiple metal-binding sites in the two major isoproteins of metallothionein from mammalian livers (rabbits, calf, and human) and from Scylla serrata hepatopancreas. The native protein isolated from the livers of rabbits that had been subjected to repeated injections of 113CdCl2 contains an appreciable amount of Zn2+ in addition to 113Cd2+, ranging from 2 to 3 g-atoms of a total metal content of 7 g-atoms/mol of protein. The native Zn2+ can be replaced in vitro with 113Cd2+ to give a 113Cd NMR spectrum consisting of eight distinct multiplets in the chemical shift range of 604-670 ppm. The multiplet structure is due to 113Cd- 113Cd scalar coupling arising from two-bond interactions between 113Cd2+ ions linked to one another by bridging cysteine thiolate ligands. Analysis of the 113Cd spectra by selective homonuclear 113Cd decoupling techniques showed that both isoproteins of rabbit liver metallothionein contain two separate metal clusters, one containing four Cd2+ ions (cluster A) and the other containing three (cluster A) and the other containing three (cluster B)
Primary Subject
Record Type
Journal Article
Journal
Federation Proceedings. Federation of American Societies for Experimental Biology; ISSN 0014-9446;
; v. 41(13); p. 2974-2980

Country of publication
AMINO ACIDS, ANIMALS, AQUATIC ORGANISMS, ARTHROPODS, BETA DECAY RADIOISOTOPES, BETA-MINUS DECAY RADIOISOTOPES, BODY, CADMIUM ISOTOPES, CARBOXYLIC ACIDS, CATTLE, CHARGED PARTICLES, DIGESTIVE SYSTEM, DOMESTIC ANIMALS, ELEMENTS, ENDOCRINE GLANDS, EVEN-ODD NUCLEI, GLANDS, INTERMEDIATE MASS NUCLEI, INVERTEBRATES, IONS, ISOMERIC TRANSITION ISOTOPES, ISOTOPE APPLICATIONS, ISOTOPES, MAMMALS, METALS, NUCLEI, ORGANIC ACIDS, ORGANIC COMPOUNDS, ORGANIC SULFUR COMPOUNDS, ORGANS, PRIMATES, RADIOISOTOPES, RUMINANTS, SPECTRA, STABLE ISOTOPES, THIOLS, TRANSITION ELEMENTS, VERTEBRATES, YEARS LIVING RADIOISOTOPES
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] Brucella abortus contains a group of immunogenic cell surface proteins which have potential value as a vaccine or as a diagnostic reagent for the prevention and diagnosis of bovine brucellosis. Under nondenaturing conditions, these proteins range in molecular weight from 10,000-124,000, as determined by high performance liquid chromatography (HPLC) on TSK 3000sw. By analytical isoelectrofocusing, 6 major protein bands could be distinguished with pI's ranging from 4.0 to 6.0 and 3 additional major proteins with pI's of 7.5, 9.5, and 10. By chromatofocusing on Polybuffer Exchanger 94 with a pH gradient from 6-4, two of the six proteins from pI 4-6 were separated, a pI 4.9 and a pI 4.7 protein; a third fraction contained the high pI proteins. The former two proteins were homogeneous by analytical isoelectrofocusing, and a molecular weight of 54,000 daltons was found for both protein species by HPLC on TSK 3000sw. The pI 4-6 and not the pI 9.5 and 10 proteins, could be radiolabeled when intact cells were radioiodinated with diazotized (125I)-iodosulfanilic acid. Biological activity of the proteins as assessed in lemmings indicated that immunization with the pI 4.7 and 4.9 proteins afforded better protection against experimental brucellosis than immunization with the high pI proteins. These results support our view that a single surface protein may be sufficient for the prevention of experimental brucellosis
Primary Subject
Source
70. annual meeting of the Federation of American Society for Experimental Biology; St. Louis, MO (USA); 13-18 Apr 1986; CONF-8604222--
Record Type
Journal Article
Literature Type
Conference
Journal
Federation Proceedings. Federation of American Societies for Experimental Biology; ISSN 0014-9446;
; CODEN FEPRA; v. 42 p. 2127

Country of publication
BACTERIA, BETA DECAY RADIOISOTOPES, CHROMATOGRAPHY, DAYS LIVING RADIOISOTOPES, DISEASES, ELECTRON CAPTURE RADIOISOTOPES, INFECTIOUS DISEASES, INTERMEDIATE MASS NUCLEI, IODINE ISOTOPES, ISOTOPE APPLICATIONS, ISOTOPES, MICROORGANISMS, NUCLEI, ODD-EVEN NUCLEI, ORGANIC COMPOUNDS, RADIOISOTOPES, SEPARATION PROCESSES, TRACER TECHNIQUES
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] Our recent studies with tritium and 14C-labeled lactate and alanine in starved rats revealed that the sites of tracer administration and sampling have a profound effect on the kinetics of the specific activity curves and the calculation of metabolic parameters. The importance of the sites of tracer administration and sampling for the experimental design and interpretation of tracer data in vivo is discussed
Primary Subject
Source
64th Annual Meeting of the Federation of American Societies for Experimental Biology; Anaheim, CA, USA; 15 Apr 1980
Record Type
Journal Article
Literature Type
Conference
Journal
Federation Proceedings. Federation of American Societies for Experimental Biology; ISSN 0014-9446;
; v. 41(1); p. 123-128

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] High-dose fractionated total lymphoid irradiation (TLI) is a safe, routine regimen used to treat patients with lymphoid malignancies. Although few side effects are associated with the regimen, a profound suppression of cell-mediated immunity is observed for several years after therapy, as judged by both in vivo and in vitro assays. A profound immunosuppression has also been observed in mice and rats given TLI. Recently, we have achieved similar results using TLI in nonmatched bone marrow transplantation in outbred dogs. The experimental work in animals and underlying cellular mechanisms are reviewed here
Primary Subject
Record Type
Journal Article
Journal
Federation Proceedings. Federation of American Societies for Experimental Biology; ISSN 0014-9446;
; v. 40(5); p. 1463-1465

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] Methods designed for estimation of the synthesis of plasma glucose are based on the transfer of 14C atoms from a selected precursor (substrate) such as lactate or alanine. This approach was shown to lead to an underestimation of the true synthesis of glucose because of the metabolic exchange of 14C atoms for 12C atoms in the hepatic oxaloacetate pool. From the incorporation of 14C atoms from intravenously infused [2-14C]acetate into plasma glucose, the extent of the metabolic exchange has been estimated. In normal dogs, metabolic exchange leads to an under-estimation of plasma glucose synthesis from plasma lactate or alanine by a factor of 2.2 +/- 0.07, i.e., by 55%. In insulin-deprived diabetic dogs, the factor was found to be 1.8 +/- 0.05. In long-term fasted dogs, the factor may be higher than in the postabsorptive state, whereas treatment with methylprednisolone has no effect. The assumptions and sources of possible errors in the estimation of the extent of metabolic exchange are reviewed
Primary Subject
Record Type
Journal Article
Journal
Federation Proceedings. Federation of American Societies for Experimental Biology; ISSN 0014-9446;
; v. 41(1); p. 104-109

Country of publication
ALDEHYDES, AMINO ACIDS, ANIMALS, BIOLOGICAL MATERIALS, BLOOD, BODY FLUIDS, CARBOHYDRATES, CARBON COMPOUNDS, CARBON ISOTOPES, CARBOXYLIC ACID SALTS, CARBOXYLIC ACIDS, EVEN-EVEN NUCLEI, HEXOSES, ISOTOPE APPLICATIONS, ISOTOPES, LIGHT NUCLEI, MAMMALS, MATERIALS, MONOSACCHARIDES, NUCLEI, ORGANIC ACIDS, ORGANIC COMPOUNDS, SACCHARIDES, STABLE ISOTOPES, SYNTHESIS, VERTEBRATES
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] Our recent studies with tritium and 14C-labeled lactate and alanine in starved rats revealed that the sites of tracer administration and sampling have a profound effect on the kinetics of the specific activity curves and the calculation of metabolic parameters. The importance of the sites of tracer administration and sampling for the experimental design and interpretation of tracer data in vivo is discussed
Primary Subject
Record Type
Journal Article
Journal
Federation Proceedings. Federation of American Societies for Experimental Biology; ISSN 0014-9446;
; v. 41(1); p. 123-128

Country of publication
AMINO ACIDS, ANIMALS, BETA DECAY RADIOISOTOPES, BETA-MINUS DECAY RADIOISOTOPES, CARBON ISOTOPES, CARBOXYLIC ACID SALTS, CARBOXYLIC ACIDS, EVEN-EVEN NUCLEI, HYDROGEN COMPOUNDS, ISOTOPE APPLICATIONS, ISOTOPES, KINETICS, LIGHT NUCLEI, MAMMALS, NUCLEI, ORGANIC ACIDS, ORGANIC COMPOUNDS, RADIOISOTOPES, REACTION KINETICS, RODENTS, VERTEBRATES, YEARS LIVING RADIOISOTOPES
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
1 | 2 | 3 | Next |