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Biomedical subjects

F Müller

Publications and source records attributed to F Müller.

At least 433 records · Page 24Linked to original sources
PubMed1984

Demonstration of locally synthesized immunoglobulin M antibodies to Treponema pallidum in the central nervous system of patients with untreated neurosyphilis.

Immunoglobulin M (IgM) antibodies to Treponema pallidum (TP) in serum and cerebrospinal fluid (CSF) can be evaluated quantitatively using a recently introduced enzyme-linked immunosorbent assay (ELISA). In 19 patients with untreated neurosyphilis, local synthesis of TP-specific IgM antibodies within the central nervous system (CNS) was demonstrated by estimation of the CSF/serum ratio of the TP-IgM-ELISA titer/mg total IgM. The TP-specific IgM antibody levels/mg total IgM in the CSF were between 3- and 75-fold higher than those in the corresponding serum of the same patients. Patients with untreated syphilis but without CNS involvement showed equal amounts of TP-specific IgM antibody levels/mg total IgM in CSF and serum, and served as controls.

Adult↗
PubMed1984

Molecular analysis of immunoglobulins M and G immune response to protein antigens of Treponema pallidum in human syphilis.

Protein antigens of Treponema pallidum precipitated by immunoglobulin M (IgM) and IgG antibodies of sera from patients with untreated primary and secondary syphilis as well as treated secondary syphilis were characterized on a molecular basis. T. pallidum was labeled internally with [35S]methionine and solubilized in 0.1% sodium dodecyl sulfate-1% Triton X-100. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis on 12.5% gels followed by autoradiography revealed 32 distinct proteins with molecular weights between 13,500 and 200,000. Twenty-three proteins of T. pallidum with molecular weights between 15,500 and 115,000 were identified as antigens by double antibody radioimmunoprecipitation with IgM and IgG antibodies of sera from syphilitic patients. The molecular analysis of the IgM and IgG immune response to T. pallidum in human syphilis is in accord with earlier immunological observations. Finally, utilizing syphilitic human sera, we characterized 15 protein antigens of T. pallidum that are common to Treponema phagedenis by partial absorption of IgM and IgG antibodies with an ultrasonicate of T. phagedenis.

Antibodies↗
PubMed1984

Molecular characterization of glycoprotein antigens on surface of Treponema pallidum: comparison with nonpathogenic Treponema phagedenis biotype Reiter.

Four glycoproteins of Treponema pallidum were identified by intrinsic [14C]glucosamine labeling. Only two glycoproteins were demonstrated in T. phagedenis biotype Reiter with the same technique. Glycoproteins of both treponemes were characterized as antigens and shown to be localized within the outer membranes of the microorganisms.

Antigens, Bacterial↗
PubMed1984

Evaluation of an enzyme immunoassay for IgM antibodies to Treponema pallidum in syphilis in man.

An enzyme immunoassay (EIA) for the detection of immunoglobulin M (IgM) antibodies to Treponema pallidum was investigated for specificity and sensitivity. Using the results in serum from 1192 patients with successfully treated syphilis, the assay was calculated to be about 97% specific. As in any other IgM enzyme linked immunosorbent assay (ELISA), rheumatoid factor played an important part in causing false positive results. Pre-absorption of serum with aggregated IgG was therefore necessary to perform the test. Evaluation of the results in serum from 385 patients with untreated primary, secondary, and latent syphilis as well as patients with untreated reinfections showed that the sensitivity of the assay depended on the stage of infection and varied between 98% and 93%. IgM antibody titres were about ten times higher in the EIA than in the indirect immunofluorescence assay using the IgM fractions of serum. From the results it may be concluded that the EIA is an appropriate technique not only for rapid and sensitive measurement of IgM antibodies in most patients with untreated syphilis but also for selecting treponemal IgM non-reactive patients.

Antibody Specificity↗
PubMed1983

[Treponema pallidium IgM enzyme-linked immunosorbent assay (TP-IgM-ELISA). Determination of organism-specific Treponema IgM antibodies in the serum of syphilis patients with and without central nervous system involvement of the infection].

For demonstration of treponemal IgM antibodies in sera and CSF taken from 56 syphilitic patients with or without involvement of the CNS in the infection, comparative studies have been performed making use of the 19S(IgM)-FTA-ABS test and a TP-IgM-ELISA. Compared with the 19S(IgM)-FTA-ABS, the TP-IgM-ELISA has a specificity of 97% and a sensitivity of 93%. With regard to qualitative investigation of serum samples, both tests showed nearly equivalent results. In 10 out of 16 CSF samples taken from patients with untreated neurosyphilis, a treponemal IgM antibody could be proved by TP-IgM-ELISA. According to these findings, this assay seems to be a reliable test system for demonstration of treponemal IgM antibodies not only in serum but also in CSF.

Antibodies, Bacterial↗
PubMed1983

[Local production of antibiotics in the CNS as a specific parameter in the immunologic diagnosis of neurosyphilis].

Concentrations of albumin and total IgG as well as TPHA-IgG antibody titres have been determined in pairs of serum and cerebrospinal fluid of 280 syphilitic patients with or without clinical symptoms of neurosyphilis. As the ratio of the TPHA-IgG titre per mg total IgG in cerebrospinal fluid and serum (CSF-TPA ratio) has been found to be a parameter for the local synthesis of treponemal IgG antibodies in the CNS, there must be assumed a participation of the CNS in syphilitic infection. In patients without participation of the CNS on the treponemal infection, the average CSF-TPA ratio is 1 with a range between 0.5 and 2.0. A local synthesis of treponemal IgG antibodies in the CNS is indicated by an increased ratio even in case of dysfunction of the blood-brain-barrier. A decreased ratio points out to a disorder of the CNS independent of te syphilitic infection. In patients with neurosiphilis having been cured ("burnt out") several decades ago the CSF-TPA ratio may return to normal possibly associated with a tissue scar in the CNS and corresponding neurological disorders.

Antibodies, Bacterial↗
PubMed1983

On the mobility of riboflavin 5'-phosphate in Megasphaera elsdenii flavodoxin as studied by 13C-nuclear-magnetic-resonance relaxation.

The mobility of the isoalloxazine ring of the prosthetic group of Megasphaera elsdenii flavodoxin was investigated by a 13C relaxation study of the non-protonated ring atoms 2, 4, 4a and 10a. In this study a selectively enriched (greater than 90% 13C) prosthetic group was bound to the apoprotein. T1 and T2 values were determined at two magnetic field strengths, i.e. 8.46 T (90.5 MHz) and 5.88 T (62.8 MHz). Values of nuclear Overhauser effects (NOE) were determined at 5.88 T. It is shown that both the dipole-dipole interaction and the chemical shift anisotropy are important relaxation sources for all the carbon atoms investigated. The results are in agreement with a spectral density function of the isoalloxazine ring in which only the overall reorientational motion of the protein is accounted for. From this it is concluded that the isoalloxazine ring is tightly associated with the apoprotein. The protein-bound isoalloxazine ring does not exhibit large fluctuations on the nanosecond time scale, although small amplitude fluctuations cannot be excluded. This information was obtained by a combination of field-dependent T1 and NOE measurements. T2 values are in agreement with these results. On the basis of the dipolar part of the overall T1 values, the distance between the carbon investigated and the nearest proton was calculated and found to be in fair agreement with the crystallographic results of the related flavodoxin from Clostridium MP. In addition, it is shown that, based on the chemical shift anisotropy as a relaxation source, information on the internal mobility is difficult to obtain. The main reason for this is the low precision in the determination of the chemical shift anisotropy tensor.

Chemical Phenomena↗
PubMed1983

The first appearance of the major divisions of the human brain at stage 9.

Five embryos of stage 9 (20 days) were studied in detail and graphic reconstructions were prepared. This is the first report based on more than one specimen of this rarely seen stage. Detailed measurements of the embryos are provided. The characteristic features of this stage are 1 to 3 pairs of somites, the head fold and foregut, the otic discs, and the pericardial cavity. The primitive streak is not decreasing as rapidly as in stage 8 but the caudal eminence is proliferating. The notochordal plate is not increasing as rapidly as in stage 8 and a notochord is not yet present. It is to be stressed that the 3 major divisions of the brain (prosencephalic, mesencephalic, and rhombencephalic) can be identified in the open neural groove. The rhombencephalon is the dominant feature of the brain and comprises 4 subdivisions, the last of which, previously unrecognized, is related to the (occipital) somites and represents the hypoglossal region. Features that may not be visible include the caudal fold and hindgut, endocardial tubes or plexus, neural crest, and neurenteric canal. In 2 specimens, atria, left ventricle, right ventricle, conotruncus, and first (or first and second) aortic arches are distinguishable. Two of the embryos studied are the earliest examples in which neural crest has been identified.

Brain↗
PubMed1983

Relationship between neurological features and intrathecal synthesis of IgG antibodies to Treponema pallidum in untreated and treated human neurosyphilis.

In syphilitic patients with or without CNS involvement the correlation of Treponema-specific IgG titre per milligram total IgG in CSF and serum (ITPA index) is a dependable source of information on the synthesis of treponemal IgG antibodies in the CNS. This index also provides a more reliable definition of asymptomatic neurosyphilis. Further, a discrimination between Treponema-specific and Treponema-non-specific IgG synthesis in the CNS is possible. Of 261 patients with clinical symptoms of neurosyphilis, 82% had a local production of treponemal IgG antibodies as shown by an elevated ITPA index. In patients with neurosyphilis and intrathecal synthesis of Treponema-specific IgG antibodies, 94% had oligoclonal IgG in the CSF. Comparison of different CSF protein alteration groups in untreated and treated neurosyphilitic patients showed that early diagnosis (and early treatment) led to improvement of the impairment of the blood-CSF barrier and reduction of the immune reaction in the CNS. However, synthesis of treponemal IgG antibodies in the CNS could persist as a 'scar syndrome' even after adequately cured infection.

Antibody Formation↗
PubMed1983

Estimation of the local production of antibodies to Treponema pallidum in the central nervous system of patients with neurosyphilis.

In 76% of 149 patients with neurosyphilis local production of treponema-specific IgG antibodies in the central nervous system (CNS) was determined by estimating the cerebrospinal fluid (CSF)-to-serum ratio of TPHA-IgG titre per mg total IgG. With this formula synthesis of treponema-specific IgG antibodies in the CNS could be detected independently of the function of the blood-CSF barrier. A selective increase of total IgG in the CSF was not found in all cases. Forty-three patients with adequately treated or spontaneously resolved syphilis without clinical evidence of involvement of the CNS by Treponema pallidum served as controls.

Albumins↗
PubMed1983

Microenzyme-linked immunosorbent assay for the detection of specific IgM antibodies in human syphilis.

An enzyme-linked immunosorbent assay (ELISA) using a highly purified soluble antigen prepared from pathogenic Treponema pallidum (Nichols) was carried out to detect specific IgM antibodies in syphilis. Serum specimens from 365 patients with untreated or treated syphilis were tested by the ELISA and by the 19S(IgM) fluorescent treponemal antibody-absorbed test. In the ELISA sera were preabsorbed with aggregated human IgG to eliminate any rheumatoid factor present. Sera from 331 healthy blood donors served as controls. The results of both tests correlated well. The specificity and sensitivity of the treponemal ELISA were both greater than 97%. The assay was easy to perform and may be automated.

Antibodies, Bacterial↗
PubMed1983

[The problem of determining Treponema-specific IgM-antibodies with the TPHA test in primary syphilis].

Approximately 10% of the investigated 49 patients with primary syphilis are non-reactive in the TPHA test if the standard technique is used. The reason for this observation can be elucidated by the ELISA technique. Only patients are affected in a second phase of immunological defence which is characterized by identical serum titres of treponemal IgM and IgG antibodies. The rate of TPHA false non-reactive results in primary syphilis can be diminished by using the test with a starting serum dilution of 1:5 instead of 1:20.

Antibodies, Bacterial↗
PubMed1983

On the inhibition of p-hydroxybenzoate hydroxylase from Pseudomonas fluorescens by adenosine nucleotides and metal ion complexes.

The flavoprotein p-hydroxybenzoate hydroxylase is inhibited by adenosine nucleotides, Cibacron blue, phosphate ions and metal ion complexes. The inhibition of the enzyme is competitive with respect to NADPH. The most potent inhibitors of the enzyme are Cibacron blue and the metal ion complexes whereas the inhibition by the adenosine nucleotides is comparable to that by halogen ions. Some inhibitors cause quenching of the fluorescence emission of the protein-bound prosthetic group or perturb the absorption spectrum of the enzyme in the visible region allowing determination of the dissociation constant of the interaction between the free or the substrate-complexed enzyme and the inhibitors. The inhibition constants are in good agreement with the dissociation constants.

Adenine Nucleotides↗
PubMed1983

The human vertebral column at the end of the embryonic period proper. 2. The occipitocervical region.

The present investigation of the cervical region of the vertebral column at eight post-ovulatory weeks is the first such study based on precise reconstructions of staged embryos. At the end of the embryonic period proper, a typical vertebra is a U-shaped piece of cartilage characterized by spina bifida occulta. The notochord ascends through the centra and leaves the dens to enter the basal plate of the skull. The median column of the axis comprises three parts (designated X, Y, Z) which persist well into the fetal period. They are related to the first, second and third cervical nerves, respectively. Part X may project into the foramen magnum and form an occipito-axial joint. Part Z appears to be the centrum of the axis. The articular columns of the cervical vertebrae are twofold, as in the adult: an anterior (atlanto-occipital and atlanto-axial) and a posterior (from the lower aspect of the axis downwards). Alar and transverse ligaments are present. Cavitation is not found in the embryonic period in either the atlanto-occipital or zygapophysial joints, and is generally not present in the median atlanto-axial joint either. Most of the transverse processes exhibit anterior and posterior tubercles. An 'intertubercular lamella' may or may not be present, i.e. the foramina transversaria are being formed around the vertebral artery. The spinal ganglia are generally partly in the vertebral canal and partly on the neural arches, medial to the articular processes. During the fetal period, the articular processes shift to a coronal position and this alteration appears to be associated with a corresponding change in the location of the spinal ganglia.

Atlanto-Axial Joint↗