The association between histological, macroscopic and magnetic resonance imaging assessed synovitis in end-stage knee osteoarthritis: a cross-sectional study.

OBJECTIVES: To investigate the association between magnetic resonance imaging (MRI), macroscopic and histological assessments of synovitis in end-stage knee osteoarthritis (KOA). METHODS: Synovitis of end-stage osteoarthritic knees was assessed using non-contrast-enhanced (CE), contrast-enhanced magnetic resonance imaging (CE-MRI) and dynamic contrast-enhanced (DCE)-MRI prior to (TKR) and correlated with microscopic and macroscopic assessments of synovitis obtained intraoperatively. Multiple bivariate correlations were used with a pre-specified threshold of 0.70 for significance. Also, multiple regression analyses with different subsets of MRI-variables as explanatory variables and the histology score as outcome variable were performed with the intention to find MRI-variables that best explain the variance in histological synovitis (i.e., highest R2). A stepped approach was taken starting with basic characteristics and non-CE MRI-variables (model 1), after which CE-MRI-variables were added (model 2) with the final model also including DCE-MRI-variables (model 3). RESULTS: 39 patients (56.4% women, mean age 68 years, Kellgren-Lawrence (KL) grade 4) had complete MRI and histological data. Only the DCE-MRI variable MExNvoxel (surrogate of the volume and degree of synovitis) and the macroscopic score showed correlations above the pre-specified threshold for acceptance with histological inflammation. The maximum R2-value obtained in Model 1 was R2 = 0.39. In Model 2, where the CE-MRI-variables were added, the highest R2 = 0.52. In Model 3, a four-variable model consisting of the gender, one CE-MRI and two DCE-MRI-variables yielded a R2 = 0.71. CONCLUSION: DCE-MRI is correlated with histological synovitis in end-stage KOA and the combination of CE and DCE-MRI may be a useful, non-invasive tool in characterising synovitis in KOA.

[Core symptoms of depression. Effectiveness of antidepressant therapy]. / Depressive Kernsymptome. Wirksamkeit medikamentöser antidepressiver Therapieverfahren.

Core symptoms of depression are a combination of psychological and somatic symptoms, often associated with psychomotor and cognitive disturbances. The diagnostic classifications of depression include the concepts of melancholic, endogenous, or severe depression. All subgroups describe severely depressed patients suffering from most of the core symptoms of depression. In addition these patients exhibit the clinical characteristics of a recurrent unipolar or bipolar course, lower placebo response rates, or higher response rates to ECT, to antidepressant treatments with dually or mixed modes of action, or to lithium augmentation. Higher rates of HPA axis hyperactivity and specific EEG patterns may also occur in this patient group. This suggests a broad overlap of patient subgroups within the diagnostic classification of depression. Because the positive diagnosis of the core symptoms of depression may include clinical consequences, it would be useful to integrate all these concepts into the upcoming new versions of the diagnostic systems DSM-V and ICD-11.

Molecular structure of the "low molecular weight antigen" of Toxoplasma gondii: a glucose alpha 1-4 N-acetylgalactosamine makes free glycosyl-phosphatidylinositols highly immunogenic.

Toxoplasma gondii is a ubiquitous parasitic protozoan causing congenital infection and severe encephalitis in the course of the acquired immunodeficiency syndrome. Glycosyl-phosphatidylinositols of T. gondii have been shown to be identical with the low molecular weight antigen which elicits an early immunoglobulin M immune response in humans. A detailed study of the structures of these glycolipid antigens was performed. Radiolabelled glycolipids were extensively analysed by chemical and exoglycosidase treatments in combination with high pH anion-exchange chromatography, gel-filtration and lectin affinity chromatography. In addition, carbohydrate fragments prepared and purified from bulk preparations of unlabelled glycolipids by high performance liquid chromatography were subjected to two-dimensional 1H nuclear magnetic resonance spectroscopy, fast-atom bombardment-mass spectrometry, and methylation linkage analysis in order to elucidate the structure of T. gondii GPIs. The following structures were identified: (ethanolamine-PO4)-Man alpha 1-2Man alpha 1-6(GalNAc beta 1-4)Man alpha 1-4GlcN alpha-inositol-PO4-lipid and the novel structure (ethanolamine-PO4)-Man alpha 1-2Man alpha 1-6(Glc alpha 1-4GalNAc beta 1-4)Man alpha 1-4 GlcN alpha-inositol-PO4-lipid both with and without terminal ethanolamine phosphate. Evidence is provided, that only T. gondii GPIs bearing the unique glucose-N-acetylgalactosamine side branch are immunogenic in humans and that this structure is widely distributed among T. gondii isolates. Monoclonal antibodies have been characterized to recognize structures with different degrees of side-chain modification. We suggest that these reagents in combination with recently devised techniques for insertional mutagenesis in T. gondii should greatly facilitate the cloning of genes essential for GPI side-chain modification.

Structure of three acidic O-linked carbohydrate chains of porcine zona pellucida glycoproteins.

Structural analysis by 1D and 2D 1H NMR spectroscopy of three acidic O-linked oligosaccharide alditols, released from porcine zona pellucida glycoproteins by alkaline borohydride treatment, afforded the following structures: Gal beta 1-4(6SO4)GlcNAc beta 1-3Gal beta 1-4GlcNAc beta 1-3Gal beta 1-3GalNAc- ol Neu5Gc alpha 2-3Gal beta 1-4(6SO4-)GlcNAc beta 1-3Gal beta 1- 4GlcNAc beta 1-3Gal beta 1-3GalNAc-ol Neu5Ac alpha 2-3Gal beta 1-4(6SO4-)GlcNAc beta 1-3Gal beta 1-4GlcNAc beta 1- 3Gal beta 1-3GalNAc-ol These oligosaccharides are the smallest compounds that contain the structural elements which are present in the acidic, high-molecular mass O-linked carbohydrate chains of porcine zona pellucida glycoproteins.

Indirect UV detection as a non-selective detection method in the qualitative and quantitative analysis of heparin fragments by high-performance capillary electrophoresis.

The application of capillary electrophoresis (CE) in combination with indirect UV detection for the qualitative and quantitative analysis of synthetic low-molecular-mass heparin fragments, at low pH, is described. It is demonstrated that, in contrast to direct UV detection, with indirect UV detection the signal obtained for various synthetic heparin pentasaccharides is nearly independent of their molecular structure. Moreover, the sensitivity of indirect UV detection is at least one order of magnitude higher than that of direct UV detection. CE-indirect UV detection for the qualitative and quantitative analysis of low-molecular-mass glycosaminoglycans was achieved by using 5 mM 5-sulphosalisylic acid, pH 3 or 5 mM 1,2,4-tricarboxybenzoic acid, pH 3.5 as electrophoresis buffer and chromophore. The technique is exemplified by the analysis of three pharmaceutical preparations of synthetic heparin pentasaccharides. The method employing indirect UV detection was validated with respect to repeatability, limit of detection, limit of quantitation, linearity, accuracy and ruggedness. In the indirect detection mode, the limit of detection for synthetic pentasaccharides is below 5 fmol, whereas the limit of quantitation is about 25 fmol. The method shows excellent repeatability and is linear in the femtomole-picomole range. Finally, it is demonstrated that the method is suitable for the analysis of various types of glycosaminoglycans.

Separation of sialyl-oligosaccharides by medium pressure anion-exchange chromatography on Mono Q.

On columns prepacked with the recently introduced anion-exchange material, Mono Q (Pharmacia), sialyl-oligosaccharides could be fractionated excellently according to the sialic acid content. With u.v. absorption at 214 nm as the detection method, analytical runs of carbohydrate material on the microgram scale, were possible. The value of the method for preparative purposes was demonstrated for sialic acid-containing carbohydrates obtained from human serotransferrin by hydrazinolysis.

Glycosyl-phosphatidylinositols in protozoa structure, biosynthesis and intracellular localisation.

We are investigating the structure and biosynthesis of glycosyl-phosphatidylinositols (GPI) in the protozoa Toxoplasma gondii, Plasmodium falciparum, Plasmodium yoelii and Paramecium primaurelia. This comparison of structural and biosynthesis data should lead us to common and individual features of the GPI-biosynthesis and transport in different organisms.

Intraperitoneal and subcutaneous injections of the TLR9 agonist ODN 1668 in rats: brain inflammatory responses are related to peripheral IL-6 rather than interferons.

Subcutaneous or intraperitoneal administration of Toll-like receptor (TLR)-9 agonist, ODN 1668 caused moderate fever and anorexia. In comparison to stimulation of other intracellular TLRs, activation of TLR9 did not result in pronounced peripheral induction of interferons, but rather induced interleukin-6. Expression of cytokines (TNFα, IL-1ß) and inducible forms of enzymes for prostaglandin E2 synthesis occurred in the brain, in conjunction with a moderate activation of the transcription factors STAT3 and NF-IL6 in brain endothelial cells. The lack of a septic-like state in ODN 1668-treated rats reinforces the therapeutic value of this drug.

Fever, sickness behavior, and expression of inflammatory genes in the hypothalamus after systemic and localized subcutaneous stimulation of rats with the Toll-like receptor 7 agonist imiquimod.

The Toll-like receptor 7 (TLR7) agonist imiquimod is used for topical treatment of skin cancers. We studied the consequences of injections of imiquimod into a subcutaneous (s.c.) air pouch or of intraperitoneal (i.p.) injections on the manifestation of fever, sickness behavior, and the peripheral and brain-intrinsic induction of a variety of inflammatory molecules. Rats were given imiqimod s.c. or i.p. (1 or 5 mg/kg). Body temperature, motor activity, and food and water intake were recorded by telemetric devices. Peripheral and brain-intrinsic induction of inflammatory mediators was analyzed by real-time polymerase chain reaction (RT-PCR), bioassays, enzyme-linked immunosorbent assays (ELISAs), and immunohistochemistry. Imiquimod is the first TLR-agonist to produce more potent effects with s.c. than i.p. administration. Peripheral induction of interferons (IFNs) and putative circulating pyrogens corresponded to the magnitude of the illness responses. In the brain, an expression of cytokines (TNFα, IL-1ß, and IL-6) and inducible forms of enzymes for prostaglandin E2 synthesis (COX-2 and mPGES) occurred, which was accompanied by a moderate activation of the transcription factors NFκB and STAT3, and a strong activation of the transcription factor NF-IL6, in cells of specific areas with an open blood-brain barrier. These inflammatory responses noted within the brain were more marked after s.c. administration, than i.p. administration of imiquimod. At a dose of 5 mg/kg, imiquimod causes rather moderate brain-inflammatory responses, which are related to peripheral IFN-expression and possibly mediated by brain-intrinsic activation of NF-IL6 and induction of a proinflammatory cocktail. The lack of a septic-like state in imiquimod-treated rats reinforces the therapeutic use of this drug.

Analysis of N-acetyl-4-O-acetylneuraminic-acid-containing N-linked carbohydrate chains released by peptide-N4-(N-acetyl-beta-glucosaminyl)asparagine amidase F. Application to the structure determination of the carbohydrate chains of equine fibrinogen.

The carbohydrate chains of equine fibrinogen were enzymatically released by peptide-N4-(N-acetyl-beta-glucosaminyl)asparagine amidase F. The oligosaccharides obtained were fractionated by a combination of FPLC and HPLC and analyzed by 500-MHz 1H-NMR spectroscopy. Four monosialo and four disialo diantennary N-acetyllactosamine type of carbohydrate chains occur: (formula; see text)

Constitutive expression and localization of COX-1 and COX-2 in rabbit iris and ciliary body.

Prostaglandins are involved in the regulation of intraocular pressure and the blood-aqueous barrier of the eye, and are used for the treatment of glaucoma. The decrease of the constitutively expressed PG-synthesizing enzyme cyclooxygenase-2 (COX-2) has been demonstrated in the ciliary non-pigmented epithelial layer of patients with primary open angle glaucoma. Little is known about the distribution of COX-1 and COX-2 in animals. We investigated this in the iris and ciliary body of the normal rabbit eye. The presence of COX-1 and COX-2 in freshly excised iris and ciliary body tissue from adult New Zealand White albino rabbits was demonstrated by real-time RT-PCR, and Western blot analysis. The localization of both isoforms and of the neuron-specific protein gene product 9.5 was determined by indirect immunofluorescence. Both enzymes are expressed in the iris and the ciliary body. Immunofluorescence studies including double staining techniques localized COX-1 and COX-2 to about 50% of cells in the stromal tissue of iris and ciliary body, mainly on the corneal side. They were co-localized in about 75% of these cells. Whereas all stained cells were positive for COX-1, COX-2 showed a gradient-like distribution in the stroma, with some restriction of expression near the epithelial layers, which we clearly showed to be completely negative for both COX-1 and COX-2. Also, neuronal elements did not show COX-1 or COX-2 immunoreactivity. These results establish the presence of COX-1 and COX-2 on the RNA and protein levels in normal, unstimulated rabbit iris and ciliary body. The pattern of distribution suggests a role for both enzymes in maintaining the physiology of the eye. In contrast to our results in man, non-pigmented epithelial cells of the ciliary body did not express immunoreactivity. This could account for differences in the regulation of intraocular pressure and/or blood-aqueous barrier between human and rabbit eyes.

Structure-function relationship of recombinant follicle stimulating hormone (Puregon).

After separation by means of preparative isoelectrofocusing, the isohormones of a Chinese hamster ovary (CHO)-derived recombinant follicle stimulating hormone (rFSH, Puregon) were characterized with respect to structural and functional features. A carbohydrate analysis revealed that rFSH isohormones with a low isoelectric point (pl) have a high sialic acid/galactose ratio and are rich in tri- and tetra-antennary N-linked carbohydrate chains in comparison with the high pl isohormones. The relative basic isohormones exhibit receptor binding activity and intrinsic bioactivity 2-3-fold higher than the relative acidic isohormones. However, due to their lower clearance rate these acidic isohormones displayed a 20-fold higher in-vivo bioactivity in the rat. A comparison of the isohormone profile of rFSH and urinary FSH (Metrodin) revealed that rFSH contains about 2-fold more basic isohormones with pl > or = 4.7 and 2-fold less acidic isohormones with pl < 4.1. In-vitro studies showed that the receptor binding affinity and intrinsic bioactivity of both FSH preparations are similar. Also the in-vivo efficacy and the pharmacokinetic behaviour of rFSH and urinary FSH in the rat were similar, which is not surprising since both preparations were compared in terms of in-vivo bioactivity calibrated in the rat Steelman-Pohley assay. However, in dogs the bioavailability of rFSH was lower than that of urinary FSH, which is in agreement with the higher percentage of relative basic isohormones in rFSH. This suggests that the pharmacokinetic behaviour of FSH in rats and dogs is different, which is supported by the much longer elimination half-life of rFSH and urinary FSH in dogs (27.9 and 30.4 h respectively) compared with rats (11.4 and 10.4 h respectively) for rFSH and urinary FSH respectively. The observed differences in pharmacokinetic behaviour in dogs and rats indicate that the rat Steelman-Pohley assay might not be a valid model for the prediction of the FSH bioactivity in species other than rat.

Kasugamycin resistant mutants of Bacillus stearothermophilus lacking the enzyme for the methylation of two adjacent adenosines in 16S ribosomal RNA.

Several mutants of B. stearothermophilus have been isolated that are resistant to the antibiotic kasugamycin. One of these is shown to lack dimethylation of two adjacent adenosines in the 16S ribosomal RNA. All mutants that were analyzed biochemically lack the enzyme that is able to methylate this site. Ribosomal sensitivity and resistance to kasugamycin in B. stearothermophilus is therefore, like in E. coli, closely connected with dimethylation of the adenosines.

Structure determination of the major N- and O-linked carbohydrate chains of the beta subunit from equine chorionic gonadotropin.

The carbohydrate moieties of equine chorionic gonadotropin alpha and beta subunits were released from the protein backbones by successive treatments with peptide-N4-(N-acetyl-beta-glucosaminyl)asparagine amidase F and alkaline borohydride and then fractionated by FPLC and HPLC. The major N- and O-linked glycans of the beta subunit were characterized by 500-MHz 1H-NMR spectroscopy, showing a remarkable structural heterogeneity for the N-glycosidically linked chains, comprising mono-, di-, tri- and tri'-antennary N-acetyllactosamine type of glycans, being partly alpha 1-6 fucosylated at the Asn-bound GlcNAc residue and having alpha 2-6 and alpha 2-3 linked N-acetyl- and N-acetyl-4-O-acetylneuraminic acid residues as sialic acid constituents. Significant differences in this respect were detected for the partially characterized glycans of the alpha subunit. The major part of the O-linked carbohydrate chains, occurring solely in the beta subunit, is formed by tri-, tetra-, penta- and hexa-saccharides. There are indications for the presence of oligo(N-acetyllactosamine) units in both the N- and O-linked glycans of the beta subunit.

Preparation and physical characteristics of a hemoglobin solution modified by coupling to 2-nor-2-formylpyridoxal 5'-phosphate.

Stroma-free hemoglobin (Hb) solutions were prepared on a 20-I scale. In 3-I batches, the beta chains of hemoglobin were crosslinked with 2-nor-2-formylpyridoxal 5'-phosphate (NFPLP) that was synthesized on a gram scale. The coupling efficiency was 60 to 80 percent. The oxygen dissociation curve of these Hb/HbNFPLP mixtures was shifted to the right with P50 (PO2 for 50% saturation with oxygen) values of 26 to 38 torr versus values of 12 to 16 torr for the nonmodified hemoglobin solutions. Both the H+ Bohr factor and the Hill coefficient were lower for the Hb/HbNFPLP mixture than for the original hemoglobin solution. The oxygen-binding coefficient beta was the same for both types of Hb solutions. The viscosity and the colloid osmotic pressure of both solutions were also the same. During storage at 4 degrees C for 18 months, no precipitation or denaturation of hemoglobin was detectable in either solution. There was also no conversion of the modified hemoglobin molecules, HbNFPLP, to the native hemoglobin tetramers, dimers, or monomers. The percentage of methemoglobin remained at 5 percent for about 6 months; it increased to 26 percent over the next 12 months. The results indicate that intramolecular coupling of hemoglobin with NFPLP yields a stable product with physiologic oxygen-carrying properties.

Separation of natural and synthetic heparin fragments by high-performance capillary electrophoresis.

The application of capillary electrophoresis (CE) for the analysis of natural and synthetic low-molecular-mass heparin fragments at low pH is described. It is demonstrated that under the applied conditions the separation is based on charge, charge distribution and molecular mass of the heparin molecules, yielding a high resolution. It is shown that the presence of sodium chloride in the sample solution has hardly any effect on the CE performance. However, the pH of the electrophoresis buffer is a critical parameter. The resolutions obtained with CE and high-performance anion-exchange chromatography (HPAEC) are compared for various heparin fragments and it is concluded that, at least for this type of molecule, CE forms an attractive alternative to HPAEC.

Structure of the O-linked carbohydrate chains of porcine zona pellucida glycoproteins.

The N-linked carbohydrate chains of porcine zona pellucida glycoproteins were released by digestion with peptide-N4-(N-acetyl-beta-glucosaminyl)asparagine amidase F and subsequently separated from the O-glycoprotein by gel-permeation chromatography on Bio-Gel P-100. The O-linked carbohydrate chains were released from the O-glycoprotein by alkaline borohydride treatment. Fractionation of the extremely heterogeneous mixture of O-linked oligosaccharide alditols was achieved by a combination of chromatographic techniques comprising gel-permeation chromatography on Bio-Gel P-4 and P-6, anion-exchange FPLC on Mono Q, and high-pH anion-exchange chromatography on CarboPac PA-1. The primary structures of 32 O-glycans were determined by one- and two-dimensional 1H-NMR spectroscopy. The major part of the analyzed compounds contain a combination of the structural elements Gal beta 1-4GlcNAc beta 1-3Gal beta 1-3GalNAc-ol, Gal beta 1-4(6SO4-)GlcNAc, and alpha 2-3-linked Neu5Gc or Neu5Ac. This series of compounds has the following structure, where n = 0 to > 6: [Neu5Gc/Ac alpha2-3]0-1[Gal beta 1-4(6SO4-)GlcNAc beta 1-3]nGal beta 1-4GlcNAc beta 1-3Gal Beta 1-3GalNAc-ol. In addition, smaller compounds were identified in which the Gal beta 1-3GalNAc-ol core is substituted by Neu5Gc/Ac alpha 2-6-linked to GalNAc-ol and/or Neu5Gc/Ac alpha 2-3-linked to Gal. Furthermore, oligosaccharides were obtained in which the distribution of 6-O-sulfated GlcNAc residues differs from that in the above-mentioned general structure, and a small portion of the oligosaccharides has the GlcNAc beta 1-3GalNAc-ol core structure. Analysis of the endo-beta-galactosidase digests of pools of N- and O-glycans indicated that the two types of oligosaccharides contain qualitatively similar poly(N-acetyllactosamine) chains. In the case of the N-linked carbohydrate chains, multiple branching of the core structures occurs, resulting in an even larger heterogeneity than observed for the O-linked carbohydrate chains.

Isolation and structure determination of the intact sialylated N-linked carbohydrate chains of recombinant human follitropin expressed in Chinese hamster ovary cells.

Biologically active recombinant human follitropin has been expressed in Chinese hamster ovary cells. The carbohydrate chains of the recombinant glycoprotein hormone were enzymatically released by peptide-N4-(N-acetyl-beta-glucosaminyl)asparagine amidase F. The oligosaccharides were separated from the N-deglycosylated protein by gel-permeation chromatography on Bio-Gel P-100, and fractionated by a combination of FPLC on Mono Q and HPLC on Lichrosorb-NH2. The structures of the carbohydrate chains were determined by 500- or 600-MHz 1H-NMR spectroscopy. The following types of carbohydrates occur: monosialylated diantennary (10%), disialylated diantennary (43%), disialylated tri-antennary (5%), trisialylated tri-antennary (13%), trisialylated tri'-antennary (8%), and tetrasialylated tetraantennary (12%) N-acetyllactosamine type of carbohydrate chains, all bearing exclusively alpha 2-3-linked N-acetylneuraminic acid (Neu5Ac). Previously, for pituitary follitropin mono-, di-, tri-, tri'-, and tetra-antennary oligosaccharides containing alpha 2-3- as well as alpha 2-6-linked Neu5Ac residues were reported. The bisecting GlcNAc residues present in native follitropin were not detected in the recombinant glycoprotein. Of the oligosaccharides 29% have an alpha 1-6-linked Fuc residue at the asparagine-bound GlcNAc, whereas this amount is about 50% in pituitary follitropin. In some of the tri-, tri'- and tetra-antennary oligosaccharide fractions small amounts (less than 5%) of compounds were detected having one or more additional N-acetyllactosamine units.

The carbohydrate chains of the beta subunit of human chorionic gonadotropin produced by the choriocarcinoma cell line BeWo. Novel O-linked and novel bisecting-GlcNAc-containing N-linked carbohydrates.

The N-linked carbohydrate chains of the beta subunit of human chorionic gonadotropin (hCG-beta) isolated from the culture fluid of the choriocarcinoma cell line BeWo were released enzymatically by peptide-N4-(N-acetyl-beta-glucosaminyl)asparagine amidase F. Subsequently, the O-linked oligosaccharides were split off from the N-deglycosylated protein by mild alkaline borohydride treatment. The carbohydrate chains were purified in their intact sialylated forms by FPLC anion-exchange chromatography on Mono Q, HPLC on Lichrosorb-NH2, and high-pH anion-exchange chromatography on CarboPac PA1. 1H-NMR spectroscopic analysis of the major fractions demonstrates the occurrence of the following sialylated diantennary and triantennary N-linked oligosaccharides. Residues not written in bold letters are variably present. [formula: see text] The incidence of triantennary carbohydrate chains is much higher than in normal urinary hCG-beta (26% vs 2%). The same holds for the alpha 1-6-fucosylation of the asparagine-bound GlcNAc (95% vs 42%). The presence of a bisecting GlcNAc and the occurrence of alpha 2-6-linked Neu5Ac in the most abundant N-glycans, are new features for hCG-beta. The major O-linked carbohydrate chains identified are the tetrasaccharide Neu5Ac alpha 2-3Gal beta 1-3(Neu5Ac alpha 2-6)GalNAc-ol and the hexasaccharide Neu5Ac alpha 2-3Gal beta 1-4GlcNAc beta 1-6(Neu5Ac alpha 2-3Gal beta 1-3)GalNAc-ol, both also found in normal urinary hCG. In addition, two novel O-glycans were characterized: [formula: see text]

Uranium cobalt tetraaluminide, UCoAl4.

The structure of UCoAl(4) can be viewed as a succession of atomic layers, with the compositions UCoAl and Al(3), that alternate along the c axis. The packing within the pure Al layer at z = 1/2 results from edge-sharing of triangles, squares and pentagons of Al atoms. Two successive Al(3) layers thus define pentagonal, square-based and trigonal prisms which are centred at z = 0 by the U, Co and remaining Al atoms. UCoAl(4) is a high-temperature phase that is only observed in as-cast samples.