Ring-chromosom 18

Zusammenfassung Wir berichten über einen Patienten mit Ring-Chromosom 18, dessen klinische Symptomatik durch Dystrophie, Minderwuchs, stato-motorische und geistige Retardierung, Mikrocephalie, Dyskranie, Mittelgesichtsdysplasie mit carpshaped mouth, Hypertelorismus, Epikanthus, Ohrmuschelanomalien, Ohrkanalstenose, beeinträchtigtes Hören, spindelförmige Finger, Muskelhypotonie, kongenitalen Herzfehler, vermehrte Wirbelbildung auf den Fingerbeeren und fehlenden IgA-Mangel ausgezeichnet ist. Phänische Merkmale der bisher publizierten Fälle mit 18r, 18p-und 18q-werden zusammengestellt und untereinander verglichen. Ein klar umrissenes 18 Ring-Syndrom läßt sich unseres Erachtens nicht abgrenzen. Alle beschriebenen 18r-Fälle zeigen klinisch Übergänge zu den Symptomkomplexen von 18p-und 18q-Patienten, so daß wir von einem 18p-/18q-—Deletionssyndrom sprechen möchten.

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Ring chromosome 1818p-/18q-—Deletion-syndrome

Summary We report a patient with ring chromosome 18, whose clinical symptoms are characterized by dystrophy, short stature, psychomotorical retardation, microcephalus dyscrania, mid-face dysplasia with carpshaped mouth, hypertelorism, epicanthus, dysplasia of the external ears, stenosis of the ear canals, hearing loss, spindle-shaped fingers, hypotonia of the muscles, congenital heart defect, increased numbers of whorles on the fingertips; there is no IgA-deficiency. The phenotypical symptoms of previously published cases with 18r, 18-and 18q-are summarized and discussed. In our opinion delineation of a separate 18 ring syndrome is not justified. All the 18r cases described in the literature clinically overlap with the 18p-and 18q-patients; we therefore suggest to call it an 18p-/18q-deletion-syndrome.

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Die cytogenetischen Untersuchungen wurden mit Unterstützung durch die Deutsche Forschungsgemeinschaft durchgeführt.     

白细胞介素18

白细胞介素-18(IL-18)是新发现的细胞因子,具有多种生物学功能.IL-18能促进外周血单个核细胞产生干扰素-γ(IFN-γ)、IL-2、粒细胞巨噬细胞集落刺激因子(GM-CSF)等细胞因子,增强天然杀伤细胞(NK细胞)的细胞毒作用.IL-18结构上与IL-1相似,而功能更接近IL-12,IL-18与IL-12均能诱导Th1细胞产生IFN-γ,存在协同效应,但它们的作用途径不同.IL-18在抗感染抗肿瘤等方面有着潜在的应用前景,并与自身免疫性疾病的发病密切相关.     

High-yielding aqueous 18F-labeling of peptides via Al18F chelation

The coordination chemistry of a new pentadentate bifunctional chelator (BFC), NODA-MPAA 1, containing the 1,4,7-triazacyclononane-1,4-diacetate (NODA) motif with a methylphenylacetic acid (MPAA) backbone, and its ability to form stable Al(18)F chelates were investigated. The organofluoroaluminates were easily accessible from the reaction of 1 and AlF(3). X-ray diffraction studies revealed aluminum at the center of a slightly distorted octahedron, with fluorine occupying one of the axial positions. The tert-butyl protected prochelator 7, which can be synthesized in one step, is useful for coupling to biomolecules on solid phase or in solution. High yield (55-89%) aqueous (18)F-labeling was achieved in 10-15 min with a tumor-targeting peptide 4 covalently linked to 1. Defluorination was not observed for at least 4 h in human serum at 37 °C. These results demonstrate the facile application of Al(18)F chelation using BFC 1 as a versatile labeling method for radiofluorinating other heat-stable peptides for positron emission imaging.     

A time-resolved fluoroimmunoassay for 18-oxocortisol and 18-hydroxycortisol. Development of a monoclonal antibody to 18-oxocortisol

Patients with primary aldosteronism and with glucocorticoid-suppressible aldosteronism excrete in the urine excessive amounts of the hybrid steroids 18-hydroxycortisol and 18-oxocortisol. The measurement of these steroids aids in the differential diagnosis of various adrenal disorders. We have produced mouse monoclonal antibodies against 18-oxocortisol and polyclonal antibodies against 18-hydroxycortisol and describe a time-resolved fluoroimmunoassay (TR-FIA) technique for the measurement of these steroids in the urine. We have also compared this assay with an ELISA technique for these compounds. We also describe the preparation of in-house Eu(III)-labeled avidin and an enhancement solution and compared to a commercially available Eu(III)-labeled streptavidin and enhancement solutions. The monoclonal antibodies against 18-oxocortisol are sensitive and have a high level of specificity. The TR-FIA technique using in-house prepared reagents or commercial ones were indistinguishable from each other, but at a significant saving. The TR-FIA technique was more sensitive and had a greater precision than the ELISA technique for both steroids.     

Prenatal diagnosis of a de novo satellited chromosome 18 (18ps) associated with 18p deletion

De novo satellited non-acrocentric chromosomes are very rare findings in prenatal diagnosis. Here we report the first case of a de novo 18ps, associated with del(18p), detected at prenatal diagnosis. A 37 years old woman underwent Chorionic Villus Sampling (CVS) for advanced maternal age. Cytogenetic analysis on direct CVS preparation (CVSc) revealed a male karyotype with a nonfamilial satellited 18ps and a reciprocal translocation t(17;19)(P11.1;q11) of maternal origin. The mesenchimal CVS culture (CVSm) showed a mosaic of cell lines with various involvement of chromosome 18: 18ps [36/70]/ r(18) [25/70]/ del(18p) [3/70]/ -18 [6/70]. Amniotic fluid cells (AFC) confirmed the homogeneous karyotype found at CVSc. The molecular cytogenetic characterization, performed on AFC, allowed the following diagnosis: 46,XY, +15, dic(15;18)(p11.1;p11.2), t(17;19)(p11.1;q11)mat. ish dic(15;18)(tel 18p-, D15Z1+, wcp18-, wcp 18+, D18Z1+, tel 18q+). The foetal autopsy disclosed subtle facial dysmorphisms and corpus callosum hypoplasia. In case of prenatal detection of de novo terminal ectopic NORs an accurate cytogenetic and molecular analysis should be performed in order to rule out subtle unbalancements.     

Contents of Volume 18

Other Index

Contents of Volume 18     

The O18 antigens (lipopolysaccharides) of Escherichia coli. Structural characterization of the O18A, O18A1, O18B and O18B1-specific polysaccharides.

The O-specific polysaccharide moieties (PS) of the O18A, O18A1, O18B, and O18B1 antigens (lipopolysaccharides, LPS) consist of L-rhamnose (Rha), N-acetyl-D-glucosamine, D-galactose, and D-glucose in different molar ratios. By using chemical fragmentation, methylation, as well as one- and two-dimensional NMR spectroscopy, the structures of these polysaccharides were found to be [formula: see text] In O18A-PS and O18A1-PS x = 2, whereas in O18B-PS and in O18B11-PS x = 3. In all four polysaccharides alpha-D-Galp (residue D) is substituted at O-3. This substituent L (residue E) is beta-D-GlcpNAc-(1 in O18A-PS and O18A1-PS and it is alpha-D-Glcp-(1 in O18B-PS and O18B1-PS. Whereas there is no further substituent on the main chain of the O18A and O18B polysaccharides, in O18A1-PS and O18B1-PS the alpha-D-GlcpNAc residue A is substituted with alpha-Glcp-(1 (residue F), which is linked to O-6 in O18A1-PS and to O-4 in O18B1-PS. These results show that the O18 antigen comprises a group of four related LPS (O18A and O18B, with their glucosylated forms O18A1 and O18B1). The results are discussed with respect to epitope definition and biochemical implications.     

Development and characterization of antisera to 18-hydroxy-corticosterone and 18-hydroxy-11-deoxycorticosterone and radioimmunoassay for serum 18-hydroxycorticosterone

A method for the production of the haptens 18-hydroxy-11-deoxycorticosterone-3-(O-carboxymethyl)-oxime (18-OH-DOC-3-CMO) and 18-hydroxycorticosterone-3-(O-carboxymethyl)-oxime (18-OH-B-3-CMO) is described. The formation of the oximes was studied in kinetic experiments. They were prepared at pH 1.6 in methanol/HC1 using a short reaction time. Antisera were raised in rabbits using serum albumin conjugates. The highly specific antisera were used at a final dilution of 1: 79 000 (18-OH-DOC) and 1: 43 000 (18-OH-B); the affinity constants were 1.2 × 10¹⁰l/mol and 8.1 × 10⁹l/mol, respectively. The radioimmunoassay procedure for 18-OH-B in serum involves purification by paper chromatography. The intra- and interassay precision was 7.3% and 12.3%, respectively. The mean serum 18-OH-B level (± S.D.) for normal male and female ambulatory subjects (n = 40) on a normal sodium diet was 0.802 ± 0.262 nmol/l. After 60 minutes of recumbency, the serum 18-OH-B level was 0.313 ± 0.061 nmol/l (n = 6) for men.