Relationship between Pain and Functional Status in Patients with Amyotrophic Lateral Sclerosis: A Multicenter Cross-Sectional Study.

BACKGROUND: Pain is a widely neglected symptom in patients with amyotrophic lateral sclerosis (ALS), even though it may be common and have a significant impact on the quality of life. OBJECTIVE: The aim of this study was to determine the frequency and characteristics of pain and its treatment in ALS patients. DESIGN: A multicenter cross-sectional study. SETTING/SUBJECTS: Eighty patients with ALS from eight hospitals. MEASUREMENTS: Data on demographics, functional status, and pharmacological treatment were collected. The Barthel Index (BI) was used to assess functional status. Pain was measured using the 0-5-point Wong-Baker FACES Pain Rating Scale. RESULTS: Pain was reported by 53.8% of ALS patients, and 36.3% reported receiving pain medication. Opioids were the drugs most commonly used to treat pain. The differences in pain frequency according to functional status were not statistically significant (p = 0.38). The pain intensity in patients whose functional status was total dependence (BI 0-20, 2.5 ± 1.2) was significantly worse than that in those with better functional status (BI 21-60, 1.4 ± 0.7; BI 61-99, 1.4 ± 0.5; p < 0.01). CONCLUSIONS: Our study indicates that all patients with ALS have the potential to suffer from pain, the intensity of which increases with decreased functional status.

Identification of tetrapyrrole compounds excreted by Rhodobacter sphaeroides and sources of the methyl hydrogens of bacteriochlorophyll a biosynthesized by R. sphaeroides, based on 13C-NMR spectral analysis of coproporphyrin III tetramethyl ester.

Red-fluorescent tetrapyrrole compounds excreted by Rhodobacter sphaeroides into the culture broth were concluded to be coproporphyrinogen (Copro'gen) III and uroporphyrinogen (Uro'gen) I, based on the (13)C-NMR spectral identification of coproporphyrin (Copro) III tetramethyl ester and uroproporphyrin (Uro) I octamethyl ester. The sources of the methyl hydrogens of bacteriochlorophyll a were established by analysis of the (13)C-NMR spectra of (2)H,(13)C-Copro III tetramethyl ester chemically derived from (2)H,(13)C-Copro'gen III biosynthesized through the feeding of delta-amino[2-(13)C]levulinic acid (ALA) to R. sphaeroides in medium containing 50% (2)H(2)O. We confirmed the previous finding that one of the methyl hydrogens was derived from water in the medium during decarboxylation of four acetyl side chains of Uro'gen III to generate Copro'gen III. It was further shown that the other hydrogen atoms, previously reported to be derived from methylene hydrogens at C-2 of ALA, had been exchanged with hydrogen of water in the medium in the biosynthetic pathways leading from ALA to Copro'gen III.