Mild untreated hypercholesterolaemia affects mechanical properties of the Achilles tendon but not gastrocnemius muscle

Tendon xanthoma and altered mechanical properties have been demonstrated in people with familial hypercholesterolaemia. However, it is unclear whether mild, untreated hypercholesterolaemia alters musculotendinous mechanical properties and muscle architecture. We conducted a case-control study of adults aged 50 years and over, without lower limb injury or history of statin medication. Based on fasting low-density lipoprotein (LDL) cholesterol levels, 6 participants had borderline high LDL (>3.33 mmol/L) and 6 had optimal LDL cholesterol (<2.56 mmol/L). Using shear wave elastography, shear wave velocity (SWV) of the Achilles tendon and gastrocnemius medialis muscle (a proxy for stiffness), along with muscle fascicle length and pennation angle were measured under four passive tensile loads (0, 0.5, 1.0, 1.5 kg) applied via a pulley system. Differences between groups were found for tendon SWV but not muscle SWV, fascicle length or pennation angle. Participants with hypercholesterolaemia showed greater SWV (mean difference, 95 % CI: 2.4 m/s, 0.9 to 4.0, P = 0.024) compared to the control group across all loads. These findings suggest that adults with mild hypercholesterolaemia have increased tendon stiffness under low passive loads, while muscle was not affected. Future research is needed to confirm findings in a larger cohort and explore the impact of hypercholesterolaemia on tendon fatigue injury and tendinopathy.

Medial gastrocnemius growth in children who are typically developing: Can changes in muscle volume and length be accurately predicted from age?

Muscle size is an important determinant of muscular fitness and health, and so it is important to have accurate estimates of actual muscle growth in children. This study compared actual versus age-predicted growth rates of the medial gastrocnemius (MG) muscle in young children over a 12-month period. Three-dimensional ultrasound was used to measure MG length and volume in 50 children (mean ± standard deviation [SD] age = 70.3 ± 29.9 months) to establish age-predicted muscle growth rates using a least-squares linear regression. Twenty children (mean ± SD age = 78.5 ± 27.2 months) were followed up at 6 and 12 months to establish actual muscle growth of MG volume and length. These data were then compared to their age-predicted muscle growth from the linear regression equation using paired t-tests and Bland-Altman limits of agreement method. Age-predicted MG growth significantly underestimated actual muscle growth for both volume and length at each timepoint. On average, actual muscle volume and length were 11.5% and 21.5% greater than the age-predicted volume and length respectively. Caution is warranted when predicting future muscle size in young children based solely on age.

Regional Variation in Muscle Echogenicity Is Related to Muscle Thickness in Young Children

Quantitative ultrasound of muscle echogenicity may be influenced by the size of the muscle and, so, corrections may be required when comparing echogenicity between populations with different muscle size. This study examined the relationship between regional muscle echogenicity and geometry in young, typically developing children (n = 49, mean ± standard deviation [SD] age = 70.8 ± 30.0 mo). Three-dimensional ultrasound was used to measure mean echo intensity (EI) and echo variation (EV), together with muscle thickness, cross-sectional area (CSA) and width, over the entire muscle length for the medial gastrocnemius (MG), rectus femoris (RF) and tibialis anterior muscles. Pearson's correlation coefficient (r) was used to assess the strength of the relationship between echogenicity and geometry using all images taken over the entire muscle length. There were moderate-strong correlations (r = 0.67-0.90) between EI and EV and thickness for each muscle, with the strongest correlations evident for the MG and RF. EI and EV were moderately correlated with muscle CSA and weakly correlated with muscle width. Normalisation of echogenicity to muscle thickness may help delineate between regions of contractile and non-contractile tissue and provide a useful measure of muscle echogenicity when comparing muscles of different cross-sectional dimensions. We recommend that researchers consider controlling for muscle size-dependent effects on echogenicity, by normalising EI and EV to muscle thickness, or including the latter as a covariate when comparing between groups.

Increased Ankle Plantar Flexor Stiffness Is Associated With Reduced Mechanical Response to Stretch in Adults With CP

Hyperexcitable stretch reflexes are often not present despite of other signs of spasticity in people with brain lesion. Here we looked for evidence that increased resistance to length change of the plantar flexor muscle-fascicles may contribute to a reduction in the stretch reflex response in adults with cerebral palsy (CP). A total of 17 neurologically intact (NI) adults (mean age 36.1; 12 female) and 13 ambulant adults with CP (7 unilateral; mean age 33.1; 5 female) participated in the study. Subjects were seated in a chair with the examined foot attached to a foot plate, which could be moved by a computer-controlled electromotor. An ultrasound probe was placed over the medial aspect of the leg to measure the length of medial gastrocnemius muscle fascicles. Slow (7 deg/s) and fast (200 deg/s) stretches with amplitude 6 deg of the plantar flexors were applied over an ankle range of 70 deg at 10 deg intervals between 60 and 130 deg plantarflexion. It was checked by EMG electrodes that the slow stretches were sufficiently slow not to elicit any activity and that the fast stretches were sufficiently quick to elicit a maximal stretch reflex in both groups. The torque elicited by the stretches was measured together with changes in the length of medial gastrocnemius muscle fascicles. Muscle fascicles increased significantly in length with increasing dorsiflexion position in both populations (p < 0.001), but the fascicles were shorter in the CP population at all positions. Slow stretches elicited significantly larger torque and significantly smaller length change of muscle fascicles as the ankle joint position was moved more towards dorsiflexion in CP than in NI (p < 0.001). Fast stretches elicited larger torque responses at ankle joint positions of 80–100 deg in the NI than in the CP group (p < 0.01). A significant negative correlation was observed between the torque response and muscle fascicle length change to slow stretch in CP (p < 0.05), but not in NI. These findings support that increased passive resistance of the ankle plantar flexor muscle-tendon unit and development of contractures may conceal stretch reflex response in adults with CP. We argue that this should be taken into account in the neurological examination of spasticity.

The size and echogenicity of the tibialis anterior muscle is preserved in both limbs in young children with unilateral spastic cerebral palsy

PURPOSE

The primary of this study was to compare the volume, length, echo intensity, and growth rate of the medial gastrocnemius (MG) and tibialis anterior (TA) muscle of both limbs (more-involved and less-involved) in children with unilateral spastic cerebral palsy (USCP), with those of an age-matched typically developing (TD) group. A secondary aim in the USCP group was to explore the associations between these muscle parameters and discrete ankle positions during phase of gait.

METHODS

Muscle parameters were assessed using 3D ultrasound. Maximal ankle dorsiflexion in stance and swing during walking were determined from 2D video analysis. Group differences in muscle size and echo intensity were assessed using a two-way analysis of covariance (age-by-group), with the interaction term used to compare muscle growth rates. Associations between muscle parameters and maximal ankle dorsiflexion in stance and swing were assessed using backwards multiple linear regression analyses.

RESULTS

The MG of both limbs in children with USCP had signs of impaired muscle development (smaller volume and length, higher echo intensity and lower growth rate). There was no evidence of impaired muscle development of TA between limbs or compared the TD children. Tibialis anterior volume, length, echo intensity and MG volume explained 66% and 83% of the variance in maximal ankle dorsiflexion position in the stance and swing phases of walking, respectively.

CONCLUSIONS

Unlike the MG, the TA volume and growth rate in children with USCP are equivalent between limbs and compared to TD children. For the more-involved limb only, TA volume, length, and echo intensity appear associated with maximal ankle dorsiflexion during walking and represent important muscle parameters that could be targeted in with early exercise therapy.Implications for rehabilitationTibialis anterior (TA) size and echogenicity appear normal in both limbs in young children with unilateral spastic cerebral palsy (USCP); findings that could indicate sufficient mechanical stimulus and muscle anabolism to maintain normal muscle growth.Tibialis anterior size and echogenicity are associated with maximal ankle dorsiflexion in both stance and swing phase of walking in young children with USCP; though such relations appear isolated to the more-involved limb.Early therapeutic interventions that target TA are likely to be successful in maintaining muscle size and may offset the negative effects of medial gastrocnemius atrophy in the development of fixed ankle equinus of the more-involved limb and improve ankle positioning during gait.

Desert crossing strategies of migrant songbirds vary between and within species

Each year, billions of songbirds cross large ecological barriers during their migration. Understanding how they perform this incredible task is crucial to predict how global change may threaten the safety of such journeys. Earlier studies based on radar suggested that most songbirds cross deserts in intermittent flights at high altitude, stopping in the desert during the day, while recent tracking with light loggers suggested diurnal prolongation of nocturnal flights and common non-stop flights for some species. We analyzed light intensity and temperature data obtained from geolocation loggers deployed on 130 individuals of ten migratory songbird species, and show that a large variety of strategies for crossing deserts exists between, but also sometimes within species. Diurnal stopover in the desert is a common strategy in autumn, while most species prolonged some nocturnal flights into the day. Non-stop flights over the desert occurred more frequently in spring than in autumn, and more frequently in foliage gleaners. Temperature recordings suggest that songbirds crossed deserts with flight bouts performed at various altitudes according to species and season, along a gradient ranging from low above ground in autumn to probably >2000 m above ground level, and possibly at higher altitude in spring. High-altitude flights are therefore not the general rule for crossing deserts in migrant songbirds. We conclude that a diversity of migration strategies exists for desert crossing among songbirds, with variations between but also within species.

Novel approaches to measuring community integration in adults with cerebral palsy

Purpose: Rehabilitation goals often focus on increasing community integration for adults with disabilities and are measured by objective assessments. Research methods have lagged behind in capturing current conceptualizations of community integration as a multidimensional construct that incorporates participation, social supports, and feelings of belonging in the community. This paper addresses this challenge by describing a multi-method approach to assessing community integration for adults with cerebral palsy.Methods: Measures include standardized questionnaires, qualitative methods, measures of function and physical activity, and geospatial measures using Geographic Information System mapping and Global Positioning System tracking. These objective and subjective data are used to determine where adults spend time and are most active, and which activities and social connections are associated with feeling integrated into the community.Results: Two case examples highlight the importance of using a multi-method approach to assess community integration for adults with cerebral palsy. Results of objective clinical measures were comparable among case examples; however, actual experiences of feeling connected to the community were vastly different.Conclusions: Multiple measures are required to capture the complexity of community integration. Relying solely on objective measures may not provide a complete picture of community integration.IMPLICATIONS FOR REHABILITATIONCommunity integration is a complex construct that incorporates participation, socialization, and feelings of belonging in the community.New methods and measures are needed to assess the many aspects of community integration in adults with disabilities.A multi-method approach is recommended to provide a richer characterization of community integration in individuals with disabilities.A combination of quantitative and qualitative measures addressing the physical, social and psychological aspects of community integration should be used.

The effect of deloading tape on medial gastrocnemius muscle fascicle behaviour during dynamic exercise

This study examined the effect of diamond deloading tape on medial gastrocnemius (MG) muscle behaviour during exercise in healthy adults (n = 27). A randomised cross-over trial assessed the effect of tape (no-tape, sham-tape and deload-tape) on ankle and MG fascicle kinematics during three heel raise-lower exercises [double leg (DL), single leg (SL) and loaded single leg (LSL)]. There was no effect of tape on standing fascicle length (FL) or pennation angle (PA), or ankle or knee joint angle. There was a significant effect of tape on ankle kinematics for all exercises. Both the deload-tape and sham-tape resulted in less ankle plantar flexion but had no effect on dorsiflexion. There was a significant effect of tape on FL change for the SL and LSL exercise. Compared to no-tape, the deload-tape resulted in less fascicle shortening during ankle plantar flexion, and more fascicle lengthening during ankle dorsiflexion. For the LSL exercise, deload-tape caused MG fascicles to operate at longer lengths, for a given joint angle. Diamond taping, with or without added tension, has only a small effect on ankle and MG fascicle kinematics during the heel raise-lower exercise. With the exception of the LSL exercise, both tape conditions resulted in similar changes in the FL-angle relations.

Characterization of torque generating properties of ankle plantar flexor muscles in ambulant adults with cerebral palsy

PURPOSE

Weakness of plantar flexor muscles is related to reduced push-off and forward propulsion during gait in persons with cerebral palsy (CP). It has not been clarified to what an extent altered muscle contractile properties contribute to this muscle weakness. Here, we investigated the torque generating capacity and muscle fascicle length in the triceps surae muscle throughout ankle range of motion (ROM) in adults with CP using maximal single muscle twitches elicited by electrical nerve stimulation and ultrasonography.

METHODS

Fourteen adults with CP (age 36, SD 10.6, GMFCS I-III) and 17 neurological intact (NI) adults (age 36, SD 4.5) participated. Plantar flexor torque during supramaximal stimulation of the tibial nerve was recorded in a dynamometer at 8 ankle angles throughout ROM. Medial gastrocnemius (MG) fascicle length was tracked using ultrasonography.

RESULTS

Adults with CP showed reduced plantar flexor torque and fascicle shortening during supramaximal stimulation throughout ROM. The largest torque generation was observed at the ankle joint position where the largest shortening of MG fascicles was observed in both groups. This was at a more plantarflexed position in the CP group.

CONCLUSION

Reduced torque and fascicle shortening during supramaximal stimulation of the tibial nerve indicate impaired contractile properties of plantar flexor muscles in adults with CP. Maximal torque was observed at a more plantarflexed position in adults with CP indicating an altered torque-fascicle length/ankle angle relation. The findings suggest that gait rehabilitation in adults with CP may require special focus on improvement of muscle contractility.

Systemic inflammatory markers in individuals with cerebral palsy

Individuals with cerebral palsy (CP) develop skeletal muscle contractures that impair muscle function. In turn, contractures affect the ability to ambulate and often promote a sedentary lifestyle. The aim of the present study was to investigate the systemic inflammatory markers transforming growth factor beta-1 (TGFβ1), C-reactive protein (CRP), and interleukin-6 (IL-6) in children and adults with CP. Blood samples of n = 34 participants (24 individuals with CP (n = 14 children with CP age 10.36 ± 1.1 and n = 10 adults with CP age 38.80 ± 3.6) and 10 healthy adults age 36.63 ± 3.8) were analyzed for circulating levels of TGFβ1, CRP, and IL-6 using Sandwich Enzyme linked immunosorbent assay (ELISA) analyses (R&D systems). TGFβ1 and CRP levels were significantly higher in children with CP compared to both adults with CP (TGFβ1: P < 0.0005 and P < 0.0002, respectively) and healthy adults (CRP: P < 0.0001 and P < 0.0001, respectively), while no differences were observed between the adults with CP and healthy adults in TGFβ1 ( P = 0.29) and CRP ( P = 0.59), respectively. Furthermore, IL-6 levels showed no significant differences between the groups. The present findings indicate that the level of systemic inflammation is increased in children with CP. We speculate that persisting inflammation in children with CP might influence the development of muscle contractures, resulting in reduced muscle mass and marked muscle weakness in adults with CP.

Validity and reliability of a freehand 3D ultrasound system for the determination of triceps surae muscle volume in children with cerebral palsy

This study assessed the validity, intra-rater and inter-rater reliability of segmentation of in vivo medial gastrocnemius (MG), lateral gastrocnemius (LG) and soleus (SOL) muscle volume measurement using a single sweep freehand 3D ultrasound (3DUS) in children with cerebral palsy (CP). The MG, LG and SOL of both limbs of 18 children with CP (age 8 years 4 months ± 1 year 10 months, 11 males, unilateral CP = 9, bilateral CP = 9, Gross Motor Functional Classification System I = 11, II = 7) were scanned using freehand 3DUS and magnetic resonance imaging (MRI). All freehand 3DUS and MRI images were segmented and volumes rendered by two raters. Validity was assessed using limits of agreement method. Intra-rater and inter-rater reliability was assessed using intra-class correlation (ICC), coefficient of variance (CV) and minimal detectable change (MDC). Freehand 3DUS overestimated muscle volume of the MG and LG by < 0.3 mL (1%) and underestimated SOL by < 1.3 mL (1.5%) compared with MRI. ICCs for intra-rater reliability of the segmentation process for the freehand 3DUS system and MRI for muscle volume were > 0.98 and 0.99, respectively, for all muscles. ICCs for inter-rater reliability of the segmentation process for freehand 3DUS and MRI volumes were > 0.96 and 0.98, respectively, for all muscles. MDCs for single rater freehand 3DUS and MRI were < 4.0 mL (14%) and 3.2 mL (11%), respectively, in all muscles. Freehand 3DUS is a valid and reliable method for the measurement of lower leg muscle volume that can be measured with a single sweep in children with CP in vivo. It can be used as an alternative to MRI for the detection of clinically relevant changes in calf muscle volume as the result of growth and interventions.

Impaired muscle growth precedes development of increased stiffness of the triceps surae musculotendinous unit in children with cerebral palsy

AIM

If increased muscle stiffness and contractures in children with cerebral palsy (CP) are related to impaired muscle growth, reduced muscle growth should precede or coincide with increased muscle stiffness during development. Here, we compared the volume of the medial gastrocnemius muscle and the passive (non-neural) stiffness of the triceps surae musculotendinous unit in typically developing children and children with CP from birth until 4 years of age.

METHOD

Forty-one children with CP and 45 typically developing children were included. Freehand three-dimensional ultrasound was used to evaluate the volume of the medial gastrocnemius muscle. Biomechanical and electrophysiological measures were used to determine passive and reflex mediated stiffness of the triceps surae musculotendinous unit.

RESULTS

Medial gastrocnemius muscle volume increased with the same rate in typically developing and children with CP until 12 months of age, when a significant smaller rate of growth was observed in children with CP. Passive stiffness of the triceps surae musculotendinous unit showed a linear increase with age in typically developing children. Children with CP older than 27 months showed a significant increase in passive stiffness. Reflex mediated stiffness was only pathologically increased in four children with CP.

INTERPRETATION

The deviation of medial gastrocnemius muscle volume, earlier than musculotendinous unit stiffness, is consistent with the hypothesis. The data also point out that muscle atrophy and muscle stiffness already develops within the first 1 to 2 years. This emphasizes the necessity of early interventions to promote lower limb muscle growth in this population.

WHAT THIS PAPER ADDS

Medial gastrocnemius muscle growth is reduced in children with cerebral palsy (CP) around 12 months after birth. Triceps surae musculotendinous unit stiffness is increased in children with CP around 27 months after birth. Reflex excitability is rarely increased in children with CP. Reduced muscle growth may be involved in the pathophysiology of contractures.

Determinants of muscle preservation in individuals with cerebral palsy across the lifespan: a narrative review of the literature

In individuals with cerebral palsy (CP), smaller muscle and atrophy are present at young age. Many people with CP also experience a decline in gross motor function as they age, which might be explained by the loss of muscle mass. The clinical observation of muscle wasting has prompted a comparison with sarcopenia in older adults, and the term accelerated musculoskeletal ageing is often used to describe the hallmark phenotype of CP through the lifespan. However, there has been very little research emphasis on the natural history of ageing with CP and even less with respect to the determinants or prevention of muscle loss with CP. Considering the burgeoning interest in the science of muscle preservation, this paper aims to (i) describe the characteristics of accelerated musculoskeletal ageing in people with CP, (ii) describe the pathophysiology of sarcopenia and parallels with CP, and (iii) discuss possible therapeutic approaches, based on established approaches for sarcopenia.

Quantitative 3-D Ultrasound of the Medial Gastrocnemius Muscle in Children with Unilateral Spastic Cerebral Palsy

Three-dimensional ultrasound (3-DUS) was used to examine the size and appearance of the medial gastrocnemius (MG) muscle in children with unilateral cerebral palsy (CP). Twenty-six children with CP and 10 typically developing (TD) children participated. Three-dimensional US images of both limbs in children with CP and the right limb in TD children were analysed using quantitative methods to determine muscle volume, global echo intensity, global echo pattern and regional echo intensity. Significant differences in MG volume and all echo parameters were found between TD and CP children. The more involved limb was smaller and had higher echo intensity and a more heterogenous echo pattern compared with the TD group. Compared with that of the more involved limb, the MG of the less involved limb was larger but had a similar echo appearance. The MG of both limbs in children with unilateral spastic CP is smaller and, based on quantitative ultrasound, structurally different from that of TD children.

Shrink rethink: rebranding psychiatry

Negative public attitudes towards psychiatry hinder individuals coming for treatment and prevent us from attracting and retaining the very brightest and best doctors. As psychiatrists we are skilled in using science to change the thoughts and behaviours of individuals, however, we lack the skills to engage entire populations. Expertise in this field is the preserve of branding, advertising and marketing professionals. Techniques from these fields can be used to rebrand psychiatry at a variety of levels from national recruitment drives to individual clinical interactions between psychiatrists and their patients.

Medial gastrocnemius and soleus muscle-tendon unit, fascicle, and tendon interaction during walking in children with cerebral palsy

AIM

This study investigates the in vivo function of the medial gastrocnemius and soleus muscle-tendon units (MTU), fascicles, and tendons during walking in children with cerebral palsy (CP) and an equinus gait pattern.

METHOD

Fourteen children with CP (9 males, 5 females; mean age 10y 6mo, standard deviation [SD] 2y 11mo; GMFCS level I=8, II=6), and 10 typically developing (6 males, 4 females; mean age 10y, SD 2y 1mo) undertook full body 3D gait analysis and simultaneous B-mode ultrasound images of the medial gastrocnemius and soleus fascicles during level walking. Fascicle lengths were analysed using a semi-automated tracking algorithm and MTUs using OpenSim. Statistical parametric mapping (two-sample t-test) was used to compare differences between groups (p<0.05).

RESULTS

In the CP group medial gastrocnemius fascicles lengthened during mid-stance gait and remained longer into late-stance compared to the typically developing group (p<0.001). CP medial gastrocnemius fascicles shortened less during stance (1.16mm [SD 1.47mm]) compared to the typically developing group (4.48mm [SD 1.94mm], p<0.001). In the CP group the medial gastrocnemius and soleus MTU and tendon were longer during early- and mid-stance (p<0.001). Ankle power during push-off (p=0.015) and positive work (p<0.002) and net work (p<0.001) were significantly lower in the CP group.

INTERPRETATION

Eccentric action of the CP medial gastrocnemius muscle fascicles during mid-stance walking is consistent with reduced volume and neuromuscular control of impaired muscle. Reduced ankle push-off power and positive work in the children with CP may be attributed to reduced active medial gastrocnemius fascicle shortening. These findings suggest a reliance on passive force generation for forward propulsion during equinus gait.

PREDICT-CP: study protocol of implementation of comprehensive surveillance to predict outcomes for school-aged children with cerebral palsy

OBJECTIVES

Cerebral palsy (CP) remains the world's most common childhood physical disability with total annual costs of care and lost well-being of $A3.87b. The PREDICT-CP (NHMRC 1077257 Partnership Project: Comprehensive surveillance to PREDICT outcomes for school age children with CP) study will investigate the influence of brain structure, body composition, dietary intake, oropharyngeal function, habitual physical activity, musculoskeletal development (hip status, bone health) and muscle performance on motor attainment, cognition, executive function, communication, participation, quality of life and related health resource use costs. The PREDICT-CP cohort provides further follow-up at 8-12 years of two overlapping preschool-age cohorts examined from 1.5 to 5 years (NHMRC 465128 motor and brain development; NHMRC 569605 growth, nutrition and physical activity).

METHODS AND ANALYSES

This population-based cohort study undertakes state-wide surveillance of 245 children with CP born in Queensland (birth years 2006-2009). Children will be classified for Gross Motor Function Classification System; Manual Ability Classification System, Communication Function Classification System and Eating and Drinking Ability Classification System. Outcomes include gross motor function, musculoskeletal development (hip displacement, spasticity, muscle contracture), upper limb function, communication difficulties, oropharyngeal dysphagia, dietary intake and body composition, participation, parent-reported and child-reported quality of life and medical and allied health resource use. These detailed phenotypical data will be compared with brain macrostructure and microstructure using 3 Tesla MRI (3T MRI). Relationships between brain lesion severity and outcomes will be analysed using multilevel mixed-effects models.

ETHICS AND DISSEMINATION

The PREDICT-CP protocol is a prospectively registered and ethically accepted study protocol. The study combines data at 1.5-5 then 8-12 years of direct clinical assessment to enable prediction of outcomes and healthcare needs essential for tailoring interventions (eg, rehabilitation, orthopaedic surgery and nutritional supplements) and the projected healthcare utilisation.

TRIAL REGISTRATION NUMBER

ACTRN: 12616001488493.

Characteristics associated with physical activity capacity and performance in children and adolescents with an acquired brain injury

AIM

To examine characteristics associated with physical activity capacity and performance in children with acquired brain injury (ABI).

METHODS

58 children (32 men; age 11 years 11 months ± 2 years 6 months; Gross motor function classification system [GMFCS] equivalent I = 29, II = 29) >12 months post ABI were recruited. Physical activity capacity measures included: (i) combined score of three 30-second repetition maximum functional strength exercises; (ii) timed up and go; (iii) 6-minute walk test and (iv) high-level mobility assessment tool (HiMAT). Physical activity performance determined time spent in sedentary, light and moderate to vigorous physical activity (MVPA). Full scale intelligence quotient (FSIQ) was assessed using the Wechsler intelligence scale for Children-IV. Regression models were constructed with functional strength score (n = 56), activity counts/minutes and time spent in MVPA and sedentary (n = 37).

RESULTS

The HiMAT and FSIQ explained 69% of the variance in functional strength. Age explained 12% of the variance in counts/min and 14% of the variance in time spent sedentary. GMFCS explained 10% of the variance in time spent in MVPA.

CONCLUSIONS

The ability to perform functional strength exercises is associated with mobility beyond independence and adequate intellectual ability for children with ABI. Age was the most significant factor associated with physical activity performance, and interventions should target adolescents with ABI.

Systematic review of physiotherapy interventions to improve gross motor capacity and performance in children and adolescents with an acquired brain injury

AIM

To systematically review the efficacy of physiotherapy interventions to improve gross motor capacity, performance and societal participation in children aged 5-17 years with an acquired brain injury (ABI).

METHODS

Randomized and non-randomized controlled trials, cohort, case series, case-control and case studies were included and classified according to grades of evidence. Methodological quality of studies was assessed using the Downs and Black (D&B) scale and quantitative data was analysed using effect sizes.

RESULTS

Two home-based studies investigated functional strength training (one randomized controlled trial, n = 20, level 2b, D&B = 16/32 and one non-randomized self-control study, n = 19, level 4, D&B = 15/32). Four studies evaluated virtual reality including: one pilot study, n = 50, level 4, D&B = 22/32; one single-subject, non-concurrent, randomized multiple baseline study, n = 3, level 4, D&B = 15/32; one case series study, n = 2, level 4, D&B = 15/32; one case study, n = 1, level 4, D&B = 15/32. Effect sizes for the randomized controlled trial ranged between 0.30-1.29 for the Functional Reach and Timed Up and Go outcome measures.

CONCLUSION

There is preliminary evidence to support the efficacy of physiotherapy interventions to improve gross motor outcomes in children with an ABI. Both functional strength training and virtual-reality based therapy are potential treatment options for clinicians to prescribe in either home or clinical settings.

Febrile neutropenia in cats treated with chemotherapy

The purpose of this study was to describe the clinical presentation, potential causative agents, treatment and outcome of febrile neutropenia (FN) in chemotherapy-treated cats. Medical records from eight institutions were retrospectively reviewed. A total of 22 FN events in 20 cats were evaluated. Lymphoma was the most common cancer diagnosis; lomustine and vinca alkaloids were the most frequently implicated causative agents. Presenting clinical signs included decreased appetite, lethargy, vomiting and diarrhoea. Median body temperature and absolute neutrophil count at presentation were 104.1 °F; 40 °C (range: 103.1-105.1 °F; 39.5-40.6 °C) and 246 mL^-1 (range: 0-1600 mL^-1 ), respectively. Median number of days between chemotherapy administration and FN onset was 5 (range: 4-25 days). All but one cat were treated with intravenous fluids and broad spectrum antibiotics. Fevers resolved in all cases and absolute neutrophil counts returned to normal in 19 cats. Clinical presentation of cats with FN appears similar to that of dogs.

Mitii™ ABI: study protocol of a randomised controlled trial of a web-based multi-modal training program for children and adolescents with an Acquired Brain Injury (ABI)

BACKGROUND

Acquired brain injury (ABI) refers to multiple disabilities arising from damage to the brain acquired after birth. Children with an ABI may experience physical, cognitive, social and emotional-behavioural impairments which can impact their ability to participate in activities of daily living (ADL). Recent developments in technology have led to the emergence of internet-delivered therapy programs. "Move it to improve it" (Mitii™) is a web-based multi-modal therapy that comprises upper limb (UL) and cognitive training within the context of meaningful physical activity. The proposed study aims to compare the efficacy of Mitii™ to usual care to improve ADL motor and processing skills, gross motor capacity, UL and executive functioning in a randomised waitlist controlled trial.

METHODS/DESIGN

Sixty independently ambulant children (30 in each group) at least 12 months post ABI will be recruited to participate in this trial. Children will be matched in pairs at baseline and randomly allocated to receive either 20 weeks of Mitii™ training (30 min per day, six days a week, with a potential total dose of 60 h) immediately, or be waitlisted for 20 weeks. Outcomes will be assessed at baseline, immediately post-intervention and at 20 weeks post-intervention. The primary outcomes will be the Assessment of Motor and Process Skills and 30 s repetition maximum of functional strength exercises (sit-to-stand, step-ups and half kneel to stand). Measures of body structure and functions, activity, participation and quality of life will assess the efficacy of Mitii™ across all domains of the International Classification of Functioning, Disability and Health framework. A subset of children will undertake three tesla (3T) magnetic resonance imaging scans to evaluate functional neurovascular changes, structural imaging, diffusion imaging and resting state functional connectivity before and after intervention.

DISCUSSION

Mitii™ provides an alternative approach to deliver intensive therapy for children with an ABI in the convenience of the home environment. If Mitii™ is found to be effective, it may offer an accessible and inexpensive intervention option to increase therapy dose.

TRIAL REGISTRATION

ANZCTR12613000403730.

The effects of botulinum toxin injection frequency on calf muscle growth in young children with spastic cerebral palsy: a 12-month prospective study

PURPOSE

This study was a 12-month prospective investigation of changes in the medial gastrocnemius (MG) muscle morphology in children aged 2-5 years with spastic cerebral palsy (CP) who had received no previous intramuscular injections of botulinum neurotoxin type-A (BoNT-A) and were randomised to receive either single or multiple (three) BoNT-A injections to the gastrocsoleus. MG morphological changes were compared to age-matched typically developing (TD) peers.

METHODS

Thirteen children with spastic CP with a mean age of 45 (15) months and 18 TD children with a mean age of 48 (14) months participated in the study. The principal outcome measures were MG muscle volume, fascicle length, pennation angle and physiological cross-sectional area (PCSA), which were obtained using 2D and 3D ultrasound.

RESULTS

The single and multiple injection frequency groups significantly increased MG muscle volume at 12 months relative to the baseline by 13 and 15 %, respectively. There were no significant differences in the MG muscle volume 28.5 (12.3) versus 30.3 (3.8) ml, fascicle length 48.0 (10.4) versus 44.8 (1.2) mm or PCSA 7.0 (1.2) versus 6.6 (1.7) cm(2) between the single and multiple injection groups, respectively, at 12 months follow-up. The change in MG muscle volume in the single and multiple injection groups was significantly lower than the TD peers by 66 and 60 %, respectively.

INTERPRETATION

In young children with spastic CP, naive to BoNT-A treatment, MG muscle growth over 12 months does not appear to be influenced by intramuscular BoNT-A injection frequency. However, MG muscle growth in the spastic CP groups was significantly lower than the age-matched TD peers. It is unclear whether this is an effect of intramuscular BoNT-A injections or reduced growth rates in children with spastic CP in general. Controlled investigations and longitudinal studies with multiple measurement time points are required in order to determine the influence of BoNT-A treatment on muscle physiological and mechanical growth factors in young children with spastic CP.

A randomized trial investigating the efficacy and safety of water soluble micellar paclitaxel (Paccal Vet) for treatment of nonresectable grade 2 or 3 mast cell tumors in dogs

BACKGROUND

Effective treatments for dogs with advanced stage mast cell tumors (MCT) remain a pressing need. A micellar formulation of paclitaxel (paclitaxel [micellar]) has shown promise in early-phase studies.

HYPOTHESIS/OBJECTIVES

The objective was to demonstrate greater activity for paclitaxel (micellar) compared with lomustine. The null hypothesis was μ(p) = μ(L) (ie, proportion of responders for the paclitaxel [micellar] and lomustine groups, respectively).

ANIMALS

Two hundred and fifty-two dogs with advanced stage nonresectable grade 2 or 3 MCT.

METHODS

Prospective multicenter randomized double-blind positive-controlled clinical trial. The primary endpoint was confirmed overall response rate (CORR) at 14 weeks. A secondary endpoint, biologic observed response rate (BORR), also was calculated. Safety was assessed by the characterization and grading of adverse events (AE).

RESULTS

Overall CORR (7% versus 1%; P = .048) and BORR (23% versus 10%; P = .012) were greater for paclitaxel (micellar) compared with lomustine. Paclitaxel (micellar)-treated dogs were 6.5 times more likely to have a confirmed response and 3.1 times more likely to experience a biologic observed response. The majority of AE with paclitaxel (micellar) were transient and clinically manageable. Twenty-seven dogs (33%) receiving lomustine were discontinued because of hepatopathy compared with 3 dogs (2%) receiving paclitaxel (micellar) (P < .0001; odds ratio 26.7).

CONCLUSIONS AND CLINICAL IMPORTANCE

Paclitaxel (micellar)'s activity and safety profile are superior to lomustine. The addition of an active and novel taxane to the veterinary armamentarium could fill a substantial need and, as its mechanism of action and AE profile do not overlap with currently available TKI, its availability could lead to effective combination protocols.

Medial gastrocnemius muscle volume and fascicle length in children aged 2 to 5 years with cerebral palsy

AIM

The aim of this article was to compare medial gastrocnemius muscle volume, physiological cross-sectional area (PCSA), muscle length, fascicle length, and pennation angle in children aged 2 to 5 years with spastic cerebral palsy (CP) and in typically developing children. method: Fifteen children with spastic CP (11 males, four females; mean age 45 mo [SD 15 mo]; five with hemiplega; 10 with diplega; 10 classified at Gross Motor Function Classification System (GMFCS) level I, five at GMFCS level II) and 20 typically developing children (11 males, nine females; mean age 48 mo [SD 14 mo]) participated in the study. Individuals with spastic CP were included if they had a minimum range of motion of 0° ankle dorsiflexion with the knee extended and were excluded if they had had previous botulinum toxin treatment to the calf muscles or previous calf surgery. Typically developing children were included if they were able to walk independently and were excluded if there was a history of previous lower leg injury or other developmental disorder affecting the lower limb. Freehand two-dimensional and three-dimensional ultrasound was used to assess muscle properties of the relaxed medial gastrocnemius muscle at three ankle joint angles: maximum dorsiflexion, neutral and maximum plantarflexion. PCSA was calculated as a function of muscle volume and muscle fascicle length and pennation angle was recorded at the neutral ankle joint angle.

RESULTS

Medial gastrocnemius muscle volume was 22% lower in the group with spastic CP than in the typically developing group, which in the absence of significant group differences in neutral fascicle length gave rise to an equivalent reduction in PCSA for the group with spastic CP. Significant positive correlations were found between muscle volume and age (r=0.63-0.65) and between muscle length and age (r=0.72-0.81) in both groups. Maximum ankle dorsiflexion angle was also reduced in the group with spastic CP (8°) compared with the typically developing group (26°).

INTERPRETATION

The observed reduction in muscle PCSA in the group with spastic CP would be expected to contribute to the clinically observed muscle weakness in spastic CP and suggests the need for early intervention in order to minimize loss of muscle PCSA in spastic CP.

Validity and reliability of a simple ultrasound approach to measure medial gastrocnemius muscle length

Fixed shortening of a muscle, or contracture, often develops in individuals with an upper motor neuron disorder. A clinical measure of muscle length would therefore be useful for identifying the presence of muscle contracture, tracking changes over time and evaluating the effect of interventions. This study compared a novel ultrasound-tape length method with a previously validated freehand 3D ultrasound method for measuring muscle length. The ultrasound-tape method intra-session reliability was also assessed. Resting medial gastrocnemius muscle length was measured at three ankle joint angles in 15 typically developed (TD) adults and nine adults with cerebral palsy (CP) using the two methods. The ultrasound-tape method on average overestimated the muscle length in the TD group by <0.1% (95% CI, 6%) and underestimated in the muscle length in the CP group by 0.1% (95% CI, 6%) compared with the 3D ultrasound method. Intra-session reliability of the ultrasound-tape method was high, with intra-class correlation coefficients >0.99. The ultrasound-tape method has sufficient accuracy to detect clinically relevant differences and changes in medial gastrocnemius muscle length and may therefore be a useful clinical tool for assessing muscle length changes associated with contracture.

Lineage differentiation of canine lymphoma/leukemias and aberrant expression of CD molecules

Multiparameter flow cytometry analysis and specific cluster differentiation (CD) molecules were used to determine the expression profiles of B- and T-cell antigens on lymph node preparations from 59 dogs with generalized or multisystemic lymphoma. Lymph node samples from 11 healthy dogs were labeled to validate the specificity of antibodies and to formulate guidelines for interpretation of the results obtained from lymphoma samples. In normal lymph nodes, T-lymphocytes expressing CD3, CD4, or CD8 beta represented 59+/-11%, 43+/-8%, or 16+/-5% of the total cells, whereas B-lymphocytes expressing either CD21 or surface IgM (IgM) represented 37+/-9% or 14+/-5%, respectively. Small lymphocytes could be distinguished from large lymphocytes by forward light scatter. Of the patient samples 29 different breeds were represented with Golden and Labrador retriever being the most common. The lymphoma samples segregated into three groups based on CD antigen expression. Thirty cases predominantly expressed one or more combinations of CD79a, IgM, and CD21 representing a B-cell lineage. Three B-cell cases also expressed the stem cell antigen, CD34. Sixteen cases expressed one or more combinations of CD3, CD4, and CD8 consistent with a T-cell lineage and CD3+CD4+CD8--phenotype was the most common. Thirteen cases showed a mixed expression profile for T- and B-cell antigens and in three cases CD14 was highly expressed. Clinical response was poorest for T-cell lymphomas. Leukemic states occurred in all three phenotypes; but mixed cell cases had the greatest proportion. Dual immunofluorescence staining confirmed co-expression of T-cell (CD3) and B-cell antigens (CD79a or CD21) on neoplastic lymphocytes of six mixed cell cases. In one mixed cell case, dual immunostaining identified lymphocyte populations that stained mutually exclusive for CD79a and CD3. Six mixed cell lymphomas tested by PCR showed clonality for rearranged antigen receptor. Four cases that were CD79a+CD3+ had TCRgamma chain gene rearrangements, whereas two cases that were CD3+CD8+CD21+ had Ig heavy chain rearrangement. One case expressing multiple CD molecules (CD3+CD8+CD21+CD14+) was PCR negative for both Ig and TCRgamma gene rearrangement and could not be classified into a B- or T-cell lineage. We show for the first time co-expression of B- and T-cell markers on lymphoma cells that had specific T- or B-cell gene rearrangements. These findings suggest that aberrant CD molecule expression is not an uncommon finding in canine lymphomas and is a useful diagnostic marker for malignancy.

Multiple, distinct isoforms of sucrose synthase in pea

Genes encoding three isoforms of sucrose synthase (Sus1, Sus2, and Sus3) have been cloned from pea (Pisum sativum). The genes have distinct patterns of expression in different organs of the plant, and during organ development. Studies of the isoforms expressed as recombinant proteins in Escherichia coli show that they differ in kinetic properties. Although not of great magnitude, the differences in properties are consistent with some differentiation of physiological function between the isoforms. Evidence for differentiation of function in vivo comes from the phenotypes of rug4 mutants of pea, which carry mutations in the gene encoding Sus1. One mutant line (rug4-c) lacks detectable Sus1 protein in both the soluble and membrane-associated fractions of the embryo, and Sus activity in the embryo is reduced by 95%. The starch content of the embryo is reduced by 30%, but the cellulose content is unaffected. The results imply that different isoforms of Sus may channel carbon from sucrose towards different metabolic fates within the cell.

Multiple, distinct isoforms of sucrose synthase in pea

Genes encoding three isoforms of sucrose synthase (Sus1, Sus2, and Sus3) have been cloned from pea (Pisum sativum). The genes have distinct patterns of expression in different organs of the plant, and during organ development. Studies of the isoforms expressed as recombinant proteins in Escherichia coli show that they differ in kinetic properties. Although not of great magnitude, the differences in properties are consistent with some differentiation of physiological function between the isoforms. Evidence for differentiation of function in vivo comes from the phenotypes of rug4 mutants of pea, which carry mutations in the gene encoding Sus1. One mutant line (rug4-c) lacks detectable Sus1 protein in both the soluble and membrane-associated fractions of the embryo, and Sus activity in the embryo is reduced by 95%. The starch content of the embryo is reduced by 30%, but the cellulose content is unaffected. The results imply that different isoforms of Sus may channel carbon from sucrose towards different metabolic fates within the cell.

[Refractory hypotension sustained during general anesthesia due to chronic treatment with angiotensin-converting enzyme inhibitors]

Perioperative management of angiotensin-converting enzyme inhibitors (ACEI) is controversial because of associated hypertensive episodes during induction and maintenance of anesthesia. A 71-year-old woman with a non-functioning thyroid node was scheduled for thyroid lobectomy. Her medical history included high blood pressure and she was being chronically treated with ACEI, which were taken until the morning of surgery. After induction of anesthesia, arterial hypotension refractory to crystalloid therapy developed and worsened in spite of administration of a gelatin-type colloid (Gelafundina). The patient did not respond to ephedrine or dopamine and required stabilization with adrenalin in continuous perfusion for 12 hours. Later evolution was satisfactory and recovery took place without sequelae. We discuss the anesthetic implications of chronic ACEI treatment and possible hemodynamic repercussions of associated administration with gelatin-type solutions or human albumin.

Differences in medical students' empathy

Medical students' Balanced Emotional Empathy Scale scores were compared by year, sex, and expressed specialty choice. Scores were lower for students choosing non-core specialties, and for M4 men students compared with M3 men students.

A prospective study of a quantitative PCR ELISA assay for the diagnosis of CMV pneumonia in lung and heart-transplant recipients

BACKGROUND

Qualitative polymerase chain reaction (PCR) for the identification of cytomegalovirus (CMV) infection has a low predictive value for the identification of CMV pneumonia. This study prospectively evaluated the application of a quantitative PCR Enzyme-Linked Immuno-Sorbent Assay (ELISA) assay in 9 lung- and 18 heart-transplant recipients who did not receive ganciclovir prophylaxis.

METHODS

DNA was collected from peripheral blood polymorphonuclear leucocytes (PMNL) posttransplantation. Oligonucleotide primers for the glycoprotein B gene (149 bp) were used in a PCR ELISA assay using an internal standard for quantitation. CMV disease was defined as histological evidence of end organ damage.

RESULTS

The median level CMV genome equivalents in patients with CMV disease was 2665/2 x 10(5) PMNL (range 1,200 to 61,606) compared to 100 x 10(5) PMNL (range 20 to 855) with infection but no CMV disease (p = 0.036). All patients with CMV disease had genome equivalents levels of >1200/2 x 10(5) PMNL. A cut-off level of 1,200 PMNL had a positive predictive value for CMV disease of 100% and a negative predictive value of 100%. The first detection of levels of CMV genome equivalents above a level of 1200/2 x 10(5) PMNL was at a median of 58 days (range 47 to 147) posttransplant.

CONCLUSIONS

Quantitative PCR assays for the diagnosis of CMV infection may predict patients at risk of CMV disease and thereby direct preemptive treatment to high-risk patients.

Canine hemangiosarcoma treated with standard chemotherapy and minocycline

Standard treatments for canine hemangiosarcoma include surgery and chemotherapy with doxorubicin, but in spite of treatment most dogs with this disease die within 6 months of diagnosis. Tumor growth and metastasis are angiogenesis dependent. Antiangiogenic drugs such as minocycline may provide therapeutic benefits in cancer patients. The purpose of this prospective study was to evaluate the efficacy of chemotherapy with doxorubicin and minocycline, an antiangiogenic agent, in dogs with hemangiosarcoma. Eighteen dogs with histologically confirmed hemangiosarcoma of any stage were treated with doxorubicin, cyclophosphamide, and minocycline. Complete staging was performed before and during the treatment period to assess remission status and response to therapy. No statistically significant difference was found in survival between the dogs treated with chemotherapy and minocycline, and historical controls consisting of dogs that received chemotherapy alone. Postmortem examination revealed widespread metastasis, suggesting that minocycline is ineffective as a single antiangiogenic agent in canine hemangiosarcoma.

The importance of stable schooling: do familiar sticklebacks stick together?

Preferences for rejoining shoals composed of familiar individuals have recently been documented in a variety of small, shallow-water fish species. Such preferences are assumed to be adaptive, since familiar groups have improved anti-predator defences and more stable dominance hierarchies. However, the design of these studies may have created conditions that elevate preferences for familiar individuals. Furthermore, in natural habitats, where significant opportunities for inter-shoal transfer may exist, it is unclear whether shoals stay together long enough for such preferences to develop. Here we present the results of a laboratory study examining whether prior familiarity influences the subsequent shoal composition of sticklebacks (Gasterosteus aculeatus) allowed to re-assort freely in a large arena tank. We show that fish from different familiarity groups associate with familiar conspecifics significantly more than predicted by a model of random assortment, suggesting that even when there is ample opportunity for inter-group transfer, shoal composition can remain stable. We discuss the phenomena that may lead to the formation of familiar groups in natural habitats. In addition, we suggest that familiarity benefits may reduce the relative value of transferring to otherwise more attractive (e.g. larger or more phenotypically matched) groups, and thereby stabilize shoal structure.

Immune-mediated neutropenia in 2 dogs

Immune‐mediated neutropenia, also termed autoimmune neutropenia (AIN), is an uncommon event, rarely documented within veterinary literature, although the clinical profile and probable pathogenesis have been outlined in detail within medical literature. In this paper, we review 2 different manifestations of this disorder. The 1st case primarily involved peripheral destruction of mature neutrophils, with little impact on marrow precursors, whereas the 2nd case resulted in suppression of neutrophilic granulopoiesis within marrow. In both cases, absolute neutrophil counts dropped below 200/mL.

The development of a quantitative PCR ELISA to determine HCMV DNAaemia levels in heart, heart/lung and lung transplant recipients

The adaptation of the polymerase chain reaction (PCR) enzyme-linked immunosorbent assay (ELISA) using a co-amplified DNA standard to quantitate the human cytomegalovirus (HCMV) glycoprotein B (gB) gene in clinical samples is described. The PCR ELISA is a solution hybridisation system with colorimetric end stage detection of amplicons. A DNA internal standard (IS) was designed by replacing a probe sequence used currently within the gB region with a heterogeneous sequence, allowing co-amplification with the same oligonucleotide primer sets and differentiation by probe hybridisation. Two DNA fragments homologous to the gB and IS sequences were generated and used for co-amplification studies to construct a standard curve. From this the copy number of the gB gene present in clinical samples could be interpolated. Co-amplification with 1000 IS copies allowed quantitation of 10-1000000 gB DNA copies in a single PCR. This assay was validated subsequently using blood samples tested by the HCMV antigenaemia assay and showed a trend of increasing HCMV DNAaemia with increasing antigenaemia levels. This rapid assay avoids using gel electrophoresis and cumbersome quantitative systems. It has the potential for early identification of patients at high risk of developing HCMV disease, and for therapeutic monitoring.

Combination therapy of cholesterol reduction and L-arginine supplementation controls accelerated vein graft atheroma

Hyperlipidemia contributes to the development of intimal hyperplasia and accelerated atheroma in vein bypass grafts. Dietary cholesterol reduction and oral supplementation with L-arginine have been shown to reduce accelerated atheroma in experimental vein grafts. This study extends these observations by examining the effect of the combination therapy of cholesterol reduction and L-arginine supplementation on the development of intimal hyperplasia in vein grafts in hypercholesterolemic animals. Thirty New Zealand White rabbits had a carotid vein bypass graft performed and were sacrificed at 28 days postoperatively either for morphology (light and electron microscopy) and videomorphometry, or for in vitro contractile studies. Twenty animals received a 1% cholesterol diet for 4 weeks prior to surgery. This diet was continued until harvest in ten animals. Ten cholesterol-fed animals received L-arginine supplementation (2 g/kg/day, p.o.) for 7 days preoperatively and thereafter until harvest and in addition were returned to a normal diet on the day of surgery. The last ten animals were controls (normal diet). Combined cholesterol reduction and L-arginine supplementation prevented accelerated atheroma in vein grafts, halted the change in enhanced smooth muscle cell contractility, and improved endothelial cell function. Early postoperative therapy targeting atheroma development in the high-risk patient could offer significant morphological and functional benefits.