Predicting spasticity after stroke in those surviving to 12 months.

OBJECTIVE: To measure muscle tone in a cohort of patients 12 months after stroke and develop a preliminary model, using data recorded routinely after stroke, to predict who will develop spasticity. DESIGN: A cohort study. SETTING: Initially hospitalized but subsequently community-dwelling stroke survivors in Liverpool, United Kingdom. SUBJECTS: One hundred and six consecutively presenting stroke patients surviving to 12 months. MAIN OUTCOME MEASURES: Spasticity measured at a range of joints using the Tone Assessment Scale. RESULTS: The Tone Assessment Scale revealed spasticity in 38 (36%) patients and more severe spasticity in 21 (20%) of the 106 patients. Logistic regression analysis revealed that lower day 7 Barthel Index score and early arm or leg weakness were significant predictors of abnormal muscle tone; and lower day 7 Barthel Index score, left-sided weakness and ever smoked to be significant predictors of more severe muscle tone. CONCLUSIONS: Using the models, it may be possible to predict whether or not spasticity will develop in patients 12 months after stroke. The utility of the models is aided by their use of predictor variables that are routinely collected as part of stroke care in hospital and which are easy to measure. The models need testing prospectively in a new cohort of patients in order to test their validity, reliability and utility and to determine if other data could improve their efficiency.

Prevalence of spasticity post stroke.

OBJECTIVES: To establish the prevalence of spasticity 12 months after stroke and examine its relationship with functional ability. DESIGN: A cohort study of prevalence of spasticity at 12 months post stroke. SETTING: Initially hospitalized but subsequently community-dwelling stroke survivors in Liverpool, UK. SUBJECTS: One hundred and six consecutively presenting stroke patients surviving to 12 months. MAIN OUTCOME MEASURES: Muscle tone measured at the elbow using the Modified Ashworth Scale and at several joints, in the arms and legs, using the Tone Assessment Scale; functional ability using the modified Barthel Index. RESULTS: Increased muscle tone (spasticity) was present in 29 (27%) and 38 (36%) of the 106 patients when measured using the Modified Ashworth Scale and Tone Assessment Scale respectively. Combining the results from both scales produced a prevalence of 40 (38%). Those with spasticity had significantly lower Barthel scores at 12 months (p < 0.0001). CONCLUSION: When estimating the prevalence of spasticity it is essential to assess both arms and legs, using both scales. Despite measuring tone at several joints, spasticity was demonstrated in only 40 (38%) patients, lower than previous estimates.

Reliability of measurements of muscle tone and muscle power in stroke patients.

OBJECTIVES: to establish the reliability of the modified Ashworth scale for measuring muscle tone in a range of muscle groups (elbow, wrist, knee and ankle; flexors and extensors) and of the Medical Research Council scale for measuring muscle power in the same muscle groups and their direct antagonists. DESIGN: a cross-sectional study involving repeated measures by two raters. We estimated reliability using the kappa statistic with quadratic weights (Kw). SETTING: an acute stroke ward, a stroke rehabilitation unit and a continuing care facility. SUBJECTS: people admitted to hospital with an acute stroke-35 patients, median age 73 (interquartile range 65-80), 20 men and 15 women. RESULTS: inter- and intra-rater agreement for the measurement of power was good to very good for all tested muscle groups (Kw = 0.84-0.96, Kw = 0.70-0.96). Inter- and intra-rater agreement for the measurement of tone in the elbow, wrist and knee flexors was good to very good (Kw = 0.73-0.96, Kw = 0.77-0.94). Inter- and intra-rater agreement for the measurement of tone in the ankle plantarflexors was moderate to good (Kw = 0.45-0.51, Kw = 0.59-0.64). CONCLUSIONS: the Medical Research Council scale was reliable in the tested muscle groups. The modified Ashworth scale demonstrated reliability in all tested muscle groups except the ankle plantarflexors. If reliable measurement of tone at the ankle is required for a specific purpose (e.g. to measure the effect of therapeutic intervention), further work will be necessary.

Reliability of the Tone Assessment Scale and the modified Ashworth scale as clinical tools for assessing poststroke spasticity.

OBJECTIVES: To establish reliability of the Tone Assessment Scale and modified Ashworth scale in acute stroke patients. SETTING: A North Liverpool university hospital. PATIENTS: Eighteen men and 14 women admitted with acute stroke and still in hospital at the study start date (median age, 74 yrs; median Barthel score, 8). MAIN OUTCOME MEASURES: The modified Ashworth scale and the Tone Assessment Scale. STUDY DESIGN: The 32 patients were examined with both scales on the same occasion by two raters (interrater comparison) and on two occasions by one rater (intrarater comparison). RESULTS: The reliability of the modified Ashworth scale was very good (kappa = .84 for interrater and .83 for intrarater comparisons). The reliability of the Tone Assessment Scale was not as strong as the modified Ashworth scale, with marked variability in the assessment of posture (kappa = .22 to .50 for interrater and .29 to .55 for intrarater comparisons) and associated reaction (kappa/kappaW = -.05 to .79 for interrater and .19 to .83 for intrarater comparisons). However, those aspects of the Tone Assessment Scale that addressed response to passive movement and that are scored similarly to the modified Ashworth scale showed good to very good interrater reliability (kappaW = .79 to .92) and good to very good intrarater reliability (kappaW = .72 to .86), except for the question related to movement at the ankle where agreement was only moderate (kappaW = .59). CONCLUSIONS: The modified Ashworth scale is reliable. The section of the Tone Assessment Scale relating to response to passive movement is reliable at various joints, except the ankle. It may assist in studies on the prevalence of spasticity after stroke and the relationship between tone and function. Further development of a measure of spasticity at the ankle is required. The Tone Assessment Scale is not reliable for measuring posture and associated reactions.

Chemoenzymic synthesis of sialylated and fucosylated oligosaccharides having an N-acetyllactosaminyl core.

Several sialylated and fucosylated oligosaccharides, based upon the N-acetyllactosaminyl core structure, have been synthesized from a single trisaccharide glycoside, beta-D-GlcNAc-(1-->3)-beta-D-Gal-(1-->4)-beta-D-GlcNAc-OCH2(CH2)++ +7CO2CH3, by the sequential use of several glycosyltransferases and one sialidase. In these chemoenzymic syntheses, selective internal monofucosylation of a dimeric N-acetyl-lactosaminyl tetrasaccharide is achieved via two routes. It is demonstrated that the pentasaccharide beta-D-Gal-(1-->4)-beta-D-GlcNAc-(1-->3)-beta-D-Gal-(1-->4)-[alpha- L-Fuc-(1-->3)]-beta-D-GlcNAc-OCH2(CH2)7-CO2CH3 is an acceptor for the rat liver beta-D-Gal-(1-->3/4)-D-Glc-NAc alpha 2,3- and beta-D-Gal-(1-->4)-D-GlcNAc alpha 2,6-sialyltransferases. Among the structures obtained is the terminal hexasaccharide of the CD-65/VIM-2 epitope.

Structure of the archaeal transfer RNA nucleoside G*-15 (2-amino-4,7-dihydro- 4-oxo-7-beta-D-ribofuranosyl-1H-pyrrolo[2,3-d]pyrimidine-5-carboximi dam ide (archaeosine)).

A number of post-transcriptional modifications in tRNA are phylogenetically characteristic of the bacterial, eukaryal, or archaeal domains, both with respect to sequence location and molecular structure at the nucleoside level. One of the most distinct such modifications is nucleoside G*, located in archaeal tRNA at position 15, which in bacterial and eukaryal tRNAs is a conserved site involved in maintenance of the dihydrouridine loop-T-loop tertiary interactions. G* occurs widely in nearly every branch of the archaeal phylogenetic domain, in contrast to its absence in all reported bacterial and eukaryal tRNA sequences. The structure of G*-15 is 2-amino-4,7-dihydro-4-oxo-7-beta-D-ribofuranosyl-1H- pyrrolo[2,3-d]pyrimidine-5-carboximidamide (7-formamidino-7-deazaguanosine), which is a non-purine, non-pyrimidine ribonucleoside; its structure thus reflects extensive modification beyond the guanine-15 specified by corresponding gene sequences. The structure was established by mass spectrometry, and in particular from collision-induced dissociation mass spectra of derivatives formed by microscale permethylation, and is confirmed by chemical synthesis.