Publications by authors named "Delbaere L"

The progression of vitiligo is unpredictable, emphasizing the need to identify periods of activity early for tailored treatment. Confetti-like depigmentation, hypochromic areas/borders and Koebner's phenomenon are clinical visible signs associated with disease activity in vitiligo. However, their true clinical significance requires further investigation using standardized scoring systems.

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There is currently no guidance on how to interpret the global degrees of activity (worsening) and repigmentation (improvement) in vitiligo. Stratification into global degrees can be completed for static evaluations (e.g.

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There is evidence of a link between disease activity in vitiligo and clinical visible signs such as confetti-like depigmentation, Koebner phenomenon and hypochromic areas/borders. Despite its established value, dermatologists and researchers continue to have a limited understanding of the vitiligo disease activity signs. The primary goal of this study was to identify 'hot spots' of disease activity signs in vitiligo patients in order to improve detection in clinical practice.

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Clinician-reported outcome measures (ClinROMs) are essential for assessment of vitiligo in clinical trials and daily practice. Several instruments have been developed and tested to measure, for example, vitiligo extent, repigmentation and activity. The goal of this review was to identify all introductory publications of ClinROMs for vitiligo that include at least some aspects of validation and to describe the instruments' characteristics, intention for use and practical strengths and limitations.

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Background: The accurate determination of the dosage of topical treatments is important given its repercussions on patient adherence and therapeutic efficacy. Up till now, the fingertip unit calculated by the rule of hands is considered the gold standard, although its use is associated with several drawbacks.

Objective: To compare different methods to estimate the affected body surface area (BSA) and dosage of topical treatments in atopic dermatitis and psoriasis and investigate its reliability, user-friendliness and timing.

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A component in seminal fluid elicits an ovulatory response and has been discovered in every species examined thus far. The existence of an ovulation-inducing factor (OIF) in seminal plasma has broad implications and evokes questions about identity, tissue sources, mechanism of action, role among species, and clinical relevance in infertility. Most of these questions remain unanswered.

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Isocitrate dehydrogenase catalyzes the first oxidative and decarboxylation steps in the citric acid cycle. It also lies at a crucial bifurcation point between CO2-generating steps in the cycle and carbon-conserving steps in the glyoxylate bypass. Hence, the enzyme is a focus of regulation.

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Background: The objective of the present study was to isolate and purify the protein fraction(s) of llama seminal plasma responsible for the ovulation-inducing effect of the ejaculate.

Methods: Semen collected from male llamas by artificial vagina was centrifuged and the seminal plasma was harvested and stored frozen. Seminal plasma was thawed and loaded onto a Type 1 macro-prep ceramic hydroxylapatite column and elution was carried out using a lineal gradient with 350 mM sodium phosphate.

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The Thermoanaerobacter ethanolicus secondary alcohol dehydrogenase I86A mutant is stereospecific for (R)-alcohols instead of (S)-alcohols. Pyramidal crystals grown in the presence of (R)-phenylethanol via the hanging-drop vapour-diffusion method diffracted to 3.2 A resolution at the Canadian Light Source.

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Wilson disease associated protein (ATP7B) is essential for copper transport in human cells. Mutations that affect ATP7B function result in Wilson's disease, a chronic copper toxicosis. Disease-causing mutations within the N-domain of ATP7B (WND) are known to disrupt ATP binding, but a high-resolution X-ray structure of the ATP-binding site has not been reported.

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Thermotoga maritima TM0298 is annotated as an alcohol dehydrogenase, yet it shows high identity and similarity to mesophilic mannitol dehydrogenases. To investigate this enzyme further, its gene was cloned and expressed in Escherichia coli. The purified recombinant enzyme was most active on fructose and mannitol, making it the first known hyperthermophilic mannitol dehydrogenase.

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Aspartates and asparagines can spontaneously cyclize with neighboring main-chain amides to form succinimides. These succinimides hydrolyze to a mixture of isoaspartate and aspartate products. Phosphorylation of aspartates is a common mechanism of protein regulation and increases the propensity for succinimide formation.

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MosA is an enzyme from Sinorhizobium meliloti L5-30, a beneficial soil bacterium that forms a symbiotic relationship with leguminous plants. MosA was proposed to catalyze the conversion of scyllo-inosamine to 3-O-methyl-scyllo-inosamine (compounds known as rhizopines), despite the MosA sequence showing a strong resemblance to dihydrodipicolinate synthase (DHDPS) sequences rather than to methyltransferases. Our laboratory has already shown that MosA is an efficient catalyst of the DHDPS reaction.

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GTP-dependent phosphoenolpyruvate carboxykinase (PCK) is the key enzyme that controls the blood glucose level during fasting in higher animals. Here we report the first substrate-free structure of a GTP-dependent phosphoenolpyruvate (PEP) carboxykinase from a bacterium, Corynebacterium glutamicum (CgPCK). The protein crystallizes in space group P2(1) with four molecules per asymmetric unit.

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The serine and cysteine proteases SspA and SspB of Staphylococcus aureus are secreted as inactive zymogens, zSspA and zSspB. Mature SspA is a trypsin-like glutamyl endopeptidase and is required to activate zSspB. Although a metalloprotease Aureolysin (Aur) is in turn thought to contribute to activation of zSspA, a specific role has not been demonstrated.

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Histidine phosphorylation is important in prokaryotes and occurs to the extent of 6% of total phosphorylation in eukaryotes. Nevertheless phosphohistidine residues are not normally observed in proteins due to rapid hydrolysis of the phosphoryl group under acidic conditions. Many rapid processes employ phosphohistidines, including the bacterial phosphoenolpyruvate:sugar phosphotransferase system (PTS), the bacterial two-component systems and reactions catalyzed by enzymes such as nucleoside diphosphate kinase and succinyl-CoA synthetase.

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Phosphoenolpyruvate carboxykinase (PCK) reversibly catalyzes the carboxylation of phosphoenolpyruvate to oxaloacetate. Carbon dioxide, and not bicarbonate ion, is the substrate utilized. Assays of the carboxylation reaction show that initial velocities are 7.

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Diffraction data have been collected from a crystal of Thermotoga maritima mannitol dehydrogenase at the Canadian Light Source. The crystal diffracted to 3.3 A resolution and belongs to space group P2(1)2(1)2(1), with unit-cell parameters a = 83.

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Phosphoenolpyruvate carboxykinase (PCK) is the key enzyme to initiate the gluconeogenic pathway in vertebrates, yeast, plants and most bacteria. Nucleotide specificity divided all PCKs into two groups. All the eukaryotic mammalian and most archaeal PCKs are GTP-specific.

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Phosphorylation of both small molecules and proteins plays a central role in many biological processes. In proteins, phosphorylation most commonly targets the oxygen atoms of Ser, Thr, and Tyr. In contrast, stably phosphorylated His residues are rarely found, due to the lability of the N-P bond, and histidine phosphorylation features most often in transient processes.

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The structure of MosA, a dihydrodipicolinate synthase and reported methyltransferase from Sinorhizobium meliloti, has been solved using molecular replacement with Escherichia coli dihydrodipicolinate synthase as the model. A crystal grown in the presence of pyruvate diffracted X-rays to 2.3 A resolution using synchrotron radiation and belonged to the orthorhombic space group C222(1), with unit-cell parameters a = 69.

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Both monomeric and dimeric NADP+-dependent isocitrate dehydrogenase (IDH) belong to the metal-dependent beta-decarboxylating dehydrogenase family and catalyze the oxidative decarboxylation from 2R,3S-isocitrate to yield 2-oxoglutarate, CO2, and NADPH. It is important to solve the structures of IDHs from various species to correlate with its function and evolutionary significance. So far, only two crystal structures of substrate/cofactor-bound (isocitrate/NADP) NADP+-dependent monomeric IDH from Azotobacter vinelandii (AvIDH) have been solved.

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Actinobacillus succinogenes can produce, via fermentation, high concentrations of succinate, an important industrial commodity. A key enzyme in this pathway is phosphoenolpyruvate carboxykinase (PCK), which catalyzes the production of oxaloacetate from phosphoenolpyruvate and carbon dioxide, with the concomitant conversion of adenosine 5'-diphosphate to adenosine 5'-triphosphate. 1.

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The 2.2 Angstroms resolution crystal structure of the enzyme phosphoenolpyruvate carboxykinase (PCK) from the bacterium Anaerobiospirillum succiniciproducens complexed with ATP, Mg(2+), Mn(2+) and the transition state analogue oxalate has been solved. The 2.

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