ABSTRACT
PURPOSE: To develop a patient-reported outcome measure for spasticity-related pain in children/adolescents (age 2-17 years) with cerebral palsy (CP), the 'Questionnaire on Pain caused by Spasticity (QPS).' METHODS: Using a semi-structured interview guide, concept elicitation interviews on spasticity-related pain in upper and lower limbs were conducted in 21 children and caregiver pairs. Data were used to modify initial QPS modules and develop six draft modules, which were subsequently refined and finalized in four consecutive cognitive interview waves (12 children and caregiver pairs). RESULTS: To accommodate the broad range in the children's communication skills, QPS child/adolescent modules were developed in both interviewer-administered and self-administered formats. With the additional parent modules, three QPS modules were developed for each of the upper and lower limb applications. Information gained from the parent/caregiver modules complements the child/adolescent assessment. Parents report observed signs and frequency of pain in the same situations used to capture the child/adolescent reports of pain severity (e.g., rest, usual daily activities, active mobilization, and physically difficult activities). Participating children/adolescents and parents/caregivers reported that the final QPS instruments were comprehensive, relevant to the child's spasticity-related experience, and easy to understand and complete. CONCLUSIONS: The QPS is a novel instrument for the assessment of spasticity-related pain in children/adolescents with CP that was developed with direct patient input. Its modules allow the use of this instrument in children/adolescents with varied levels of impairment and communication skills.
Subject(s)
Cerebral Palsy/psychology , Muscle Spasticity/complications , Pain/psychology , Patient Outcome Assessment , Surveys and Questionnaires , Adolescent , Adult , Caregivers/psychology , Cerebral Palsy/complications , Child , Child, Preschool , Female , Humans , Interviews as Topic , Male , Middle Aged , Muscle Spasticity/psychology , Pain/etiology , Pain Measurement/methods , Pediatrics/statistics & numerical data , Qualitative Research , Quality of Life , United States , Young AdultABSTRACT
Methylenetetratetrahydromethanopterin reductase (Mer) is involved in CO(2) reduction to methane in methanogenic archaea and catalyses the reversible reduction of methylenetetrahydromethanopterin (methylene-H(4)MPT) to methyl-H(4)MPT with coenzyme F(420)H(2), which is a reduced 5'-deazaflavin. Mer was recently established as a TIM barrel structure containing a nonprolyl cis-peptide bond but the binding site of the substrates remained elusive. We report here on the crystal structure of Mer in complex with F(420) at 2.6 A resolution. The isoalloxazine ring is present in a pronounced butterfly conformation, being induced from the Re-face of F(420) by a bulge that contains the non-prolyl cis-peptide bond. The bindingmode of F(420) is very similar to that in F(420)-dependent alcohol dehydrogenase Adf despite the low sequence identity of 21%. Moreover, binding of F(420) to the apoenzyme was only associated with minor conformational changes of the polypeptide chain. These findings allowed us to build an improved model of FMN into its binding site in bacterial luciferase, which belongs to the same structural family as Mer and Adf and also contains a nonprolyl cis-peptide bond in an equivalent position.
Subject(s)
Bacterial Proteins/chemistry , Luciferases/chemistry , Oxidoreductases Acting on CH-NH Group Donors/chemistry , Oxidoreductases Acting on CH-NH Group Donors/metabolism , Peptides/chemistry , Riboflavin/analogs & derivatives , Alcohol Oxidoreductases/chemistry , Alcohol Oxidoreductases/genetics , Alcohol Oxidoreductases/metabolism , Amino Acid Sequence , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Binding Sites , Catalysis , Crystallography, X-Ray , Flavin Mononucleotide/chemistry , Flavin Mononucleotide/metabolism , Flavins , Luciferases/genetics , Luciferases/metabolism , Methanobacterium/enzymology , Methanobacterium/genetics , Methanobacterium/metabolism , Models, Molecular , Molecular Sequence Data , Oxidoreductases Acting on CH-NH Group Donors/genetics , Peptides/genetics , Peptides/metabolism , Proline/chemistry , Proline/genetics , Proline/metabolism , Protein Binding , Protein Conformation , Riboflavin/chemistry , Riboflavin/metabolism , Sequence Homology, Amino AcidABSTRACT
F(420)-dependent secondary alcohol dehydrogenase (Adf) from methanogenic archaea is a member of the growing bacterial luciferase family which are all TIM barrel enzymes, most of which with an unusual nonprolyl cis peptide bond. We report here on the crystal structure of Adf from Methanoculleus thermophilicus at 1.8 A resolution in complex with a F(420)-acetone adduct. The knowledge of the F(420) binding mode in Adf provides the molecular basis for modeling F(420) and FMN into the other enzymes of the family. A nonprolyl cis peptide bond was identified as an essential part of a bulge that serves as backstop at the Re-face of F(420) to keep it in a bent conformation. The acetone moiety of the F(420)-acetone adduct is positioned at the Si-face of F(420) deeply buried inside the protein. Isopropanol can be reliably modeled and a hydrogen transfer mechanism postulated. His39 and Glu108 can be identified as key players for binding of the acetone or isopropanol oxygens and for catalysis.
