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Objective: The main purposes of this study were to examine, in subjects with chronic hemiparesis following a stroke: (i) the correlations between tests of muscle tone, stiffness, spasticity, paresis and co-contraction, and (ii) the correlations of these tests and measurements of impairment to upper extremity motor performance.Design: Prospective, cross-sectional, correlation matrix using sample of convenience.Subjects: Thirteen subjects with chronic hemiparesis secondary to a cerebrovascular accident (stroke) were tested.Methods: Subjects were assessed using the Fugl-Meyer Upper Extremity Motor Assessment, modified Ashworth scale, deep tendon reflexes, and muscle characteristics that included quantification of muscle stiffness, paresis and co-contraction during a voluntary reaching task and during passive movements. Surface electromyographic and myotonometric muscle stiffness data were obtained during movement trials.Results: Biceps and triceps brachii muscle paresis and excess biceps brachii co-contraction during voluntary reaching had the highest correlations to decreased motor performance. Muscle tone measurements did not have significant correlations to upper extremity performance.Conclusion: Paresis of elbow flexors and extensors and excess co-contraction of the biceps brachii during voluntary reaching appear to be most predictive of upper extremity motor performance. Results are discussed in relation to the specific challenges these findings pose for spastic paresis clinical management. [ABSTRACT FROM AUTHOR]

Background: Changes in the modulation of soleus alpha motoneuron excitability, as assessed by H reflexes, and temporal sequencing of the soleus and tibialis anterior muscles during voluntary ankle dorsiflexions and plantar flexions of young (24.7 +/- 11.5; n = 13) and older (68.7 +/- 5.4; n = 13) subjects were assessed to determine potential neural mechanisms that might contribute to motor control changes associated with aging.Methods: A repetitive stimulation (5 Hz) soleus H-reflex testing protocol and surface electromyography (EMG) were used to assess the latencies of soleus H-reflex changes in relation to tibialis anterior and soleus EMG activations of standing subjects during voluntary ankle dorsiflexions and plantar flexions at self-selected speeds. The pattern and latency of H-reflex changes in relation to EMG activity were compared between young and old subjects.Results: There were no differences in the relative amount of antagonist muscle (soleus) inhibition during voluntary ankle dorsiflexions between young and old subjects (26.4% and 27.2% decrease from resting H-reflex values, respectively). Older subjects, however, required additional time to achieve these levels of inhibition. Delays in the activation of soleus H reflexes during the plantar flexion task were also observed in older subjects. Older subjects also had considerable intra- and intersubject variability in muscle temporal sequencing patterns during ankle plantar flexions.Conclusions: Although older subjects exhibited similar relative levels of alpha motoneuron inhibition and excitation during voluntary movements, this modulation was delayed when compared to younger subjects. Temporal sequencing of distal muscle activations also appears to undergo change with aging. [ABSTRACT FROM AUTHOR]

We present the complete chloroplast genome sequence of Rhodochorton tenue from San Juan Island, Washington. The chloroplast genome of R. tenue is 192,037 bp in length, contains 244 genes, and is similar in content to Acrochaetium secundatum. Rhodochorton tenue is genetically distinct from Rhodochorton purpureum from the North Atlantic Ocean., Competing Interests: The authors declare no conflict of interest.

The present study investigated the effects of aging on the distribution of common descending neural drives to main postural muscles acting on the ankle, knee, hip, and lower trunk. The presence, distribution, and strength of these drives were assessed using intermuscular coherence estimations at a low-frequency band (0-55 Hz). Ten healthy older adults (68.7 ± 3.5 years) with no recent history of falls and ten healthy younger adults (26.8 ± 2.7 years) performed bipedal stances with eyes either opened or closed. Electromyographic (EMG) signals of six postural muscles were recorded. Estimations of intermuscular coherence were obtained from fifteen muscle pairs and four muscle groups. In general, single-pair and pooled coherence analyzes revealed significant levels of signal synchronization within 1-10 Hz. Significant common drives to anterior, posterior, and antagonist muscle groups were observed for both cohorts of participants. However, older participants showed significantly stronger EMG-EMG synchronization in the frequency domain compared to younger participants. It seems that age-related sarcopenia, visual-vestibular-proprioceptive decline, cortical activation increase, presynaptic inhibition modulation decrease, and co-contraction increase had a major impact on strengthening the common drives to the aforementioned muscle groups. Differently from young adults, the absence of visual inputs did not reduce the magnitude of signal synchronization in older adults. These results suggest that the aging central nervous system seems to organize similar arrangements of common drives to postural antagonist muscles at different joints, and to postural muscles pushing the body either forward or backward when visual information is not available.

Technical advancements in instrumentation and analytical methods have improved the ability of assessing balance control. This study investigated the effects of early stages of aging on postural sway using traditional and contemporary postural indices from different domains. Eleven healthy young adults and fourteen healthy non-faller older adults performed two postural tasks: (a) functional limits of stability and (b) unperturbed bipedal stance for 120s. Postural indices from spatial, temporal, frequency, and structural domains were extracted from the body's center of pressure (COP) signals and its Rambling and Trembling components. Results revealed a preservation of functional limits of upright stability in older adults accompanied by larger, faster, and shakier body sway in both anterior-posterior and medio-lateral directions; increased medio-lateral sway frequency; increased irregularity of body sway pattern in time in both directions; and increased area, variability, velocity, and jerkiness of both rambling and trembling components of the COP displacement in the anterior-posterior direction (p<0.02). Such changes might be interpreted as compensatory adjustments to the age-related decline of sensory, neural, and motor functions. In conclusion, balance assessment using postural indices from different domains extracted from the COP displacement was able to capture subtle effects of the natural process of aging on the mechanisms of postural control. Our findings suggest the use of such indices as potential markers for postural instability and fall risk in older adults., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The overall goal of this study was to investigate potential adaptations brought about by the natural processes of aging on the coordination of postural muscles. Considering the progressive and non-homogeneous deterioration of sensorimotor and neuromuscular systems as the individual grows older, it was hypothesized that aging is associated with a reorganization of synergistic mechanisms controlling postural muscles. Therefore, the presence, distribution, and strength of correlated neural inputs to three posterior postural muscles were measured by intermuscular coherence estimations at a low frequency band (0-55Hz). Nine healthy young adults and thirteen healthy older adults performed ten trials of a perturbed task: bipedal stance while holding a five kg load for fifteen seconds. Estimates of intermuscular coherence for each pair of electromyographic signals (soleus and biceps femoris, soleus and erector spinae, and biceps femoris and erector spinae) were computed. Results revealed significantly stronger levels of synchronization of posterior muscles within 0-10Hz in seniors compared to young adults. In addition, seniors presented similar spectra of intermuscular coherence within 0-55Hz for all three muscle pairs analyzed. These findings provide valuable information regarding compensatory mechanisms adopted by older adults to control balance. The age-related reorganization of neural drive controlling posterior postural muscles revealing a stronger synchronization within 0-10Hz might be related to the faster body sway and muscle co-activation patterns usually observed in this population. Finally, this study supports the use of Intermuscular Coherence Analysis as a sensitive method to detect age-related changes in multi-muscle control., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Primary Objective: The purpose of this study was to investigate the effects of mild traumatic brain injury (mTBI) on multiple postural indices that characterize body sway behaviour., Methods and Procedures: The body's centre of pressure (COP) displacement was recorded from 11 individuals with a history of mTBI (29.4 ± 6.7 years old) and 11 healthy controls (26.8 ± 3.7 years old) performing bipedal stance on a force platform for 120 seconds. Spatio-temporal (area, amplitude and mean velocity of the COP displacement) and frequency characteristics (frequency containing 80% of the power spectral density) of the body oscillation, as well as its dynamic characteristics (sample entropy estimate of the COP displacement) were extracted from COP signals., Main Outcomes and Results: All postural indices studied were significantly affected by mTBI (p < 0.010). Participants with a history of mTBI presented a larger, slower, and more random body oscillation compared to controls., Conclusion: The results suggest that (a) balance deficits can be recognized as an effect of mTBI; (b) balance deficits induced by mTBI are multi-dimensional, affecting all three domains included in this study; and, ((c) the postural indices employed in this study are potential markers to detect changes in postural control following mTBI.)

The current study used transcranial magnetic stimulation (TMS) of the right primary motor cortex (M1) during bimanual contractions to examine facilitatory and inhibitory influences on the contralateral, target extensor carpi radialis muscle (ECR) during changes in the task demands of the ipsilateral (task) ECR. The bimanual contractions were either mirrored (isometric wrist extension bilaterally) or more difficult asynergistic (asymmetric [wrist extension paired with wrist radial deviation]) contractions. TMS-induced motor evoked potentials (MEPs) and cortical silent periods (CSPs) were recorded during the execution of visually guided ramp and hold tasks. It was of interest to determine whether or not asynergistic contractions, representing a more difficult bimanual coordination task, resulted in differing patterns of activation and inhibition than mirrored movements. Asynergistic contractions were found to have differing effects on the target ECR than mirrored contractions. Foremost among these differences were the presence of enhanced inhibitory mechanisms. During asynergistic bimanual contractions the MEPs of the target ECR did not increase to the same degree and cortical silent period durations were longer. Findings indicate that bimanual mirrored and asynergistic contractions result in differing patterns of corticomotor excitability., (Published by Elsevier B.V.)

Standing upright requires the coordination of neural drives to a large set of muscles involved in controlling human bipedal stance (i.e., postural muscles). The coordination may deteriorate in situations where standing is performed under more challenging circumstances, such as standing on a smaller base of support or not having adequate visual information. The present study investigates the role of common neural inputs in the organization of multi-muscle synergies and the effects of visual input disruption to this mechanism of control. We analyzed the strength and distribution of correlated neural inputs (measured by intermuscular coherence) to six postural muscles previously recognized as components of synergistic groups involved in the maintenance of the body's vertical positioning. Two experimental conditions were studied: quiet bipedal stance performed with opened eyes (OEs) and closed eyes (CEs). Nine participants stood quietly for 30 s while the activity of the soleus, biceps femoris, lumbar erector spinae, tibialis anterior, rectus femoris, and rectus abdominis muscles were recorded using surface electrodes. Intermuscular (EMG-EMG) coherence was estimated for 12 muscle pairs formed by these muscles, including pairs formed solely by either posterior, anterior, or mixed (one posterior and one anterior) muscles. Intermuscular coherence was only found to be significant for muscle pairs formed solely by either posterior or anterior muscles, and no significant coherence was found for mixed muscle pairs. Significant intermuscular coherence was only found within a distinct frequency interval bounded between 1 and 10 Hz when visual input was available (OEs trials). The strength of correlated neural inputs was similar across muscle pairs located in different joints but executing a similar function (pushing body either backward or forward) suggesting that synergistic postural groups are likely formed based on their functional role instead of their anatomical location. Absence of visual information caused a significant decrease in intermuscular coherence. These findings are consistent with the hypothesis that correlated neural inputs are a mechanism used by the CNS to assemble synergistic muscle groups. Further, this mechanism is affected by interruption of visual input.

Posture and postural reactions to mechanical perturbations require the harmonic modulation of the activity of multiple muscles. This precision can become suboptimal in the presence of neuromuscular disorders and result in higher fall risk and associated levels of comorbidity. This study was designed to investigate neurophysiological principles related to the generation and distribution of inputs to skeletal muscles previously recognized as a synergistic group. Specifically, we investigated the current hypothesis that correlated neural inputs, as measured by intermuscular coherence, are the mechanism used by the central nervous system to coordinate the formation of postural muscle synergies. This hypothesis was investigated by analyzing the strength and distribution of correlated neural inputs to postural muscles during the execution of a quiet stance task. Nine participants, 4 females and 5 males, mean age 29.2 years old (±6.1 SD), performed the task of standing while holding a 5-kg barbell in front of their bodies at chest level. Subjects were asked to maintain a standing position for 10 s while the activity of three postural muscles was recorded by surface electrodes: soleus (SOL), biceps femoris (BF), and lumbar erector spinae (ERE). EMG-EMG coherence was estimated for three muscle pairs (SOL/BF, SOL/ERE, and BF/ERE). Our choice of studying these muscles was made based on the fact that they have been reported as components of a functional (synergistic) muscle group that emerges during the execution of bipedal stance. In addition, an isometric contraction can be easily induced in this muscle group by simply adding a weight to the body's anterior aspect. The experimental condition elicited a significant increase in muscle activation levels for all three muscles (p < 0.01 for all muscles). EMG-EMG coherence analysis revealed significant coherence within two distinct frequency bands, 0-5 and 5-20 Hz. Significant coherence within the later frequency band was also found to be significantly uniformly distributed across the three muscle pairs. These findings are interpreted as corroborative with the idea of a hierarchic system of control where the controller may use the generation of common neural inputs to reduce the number of variables it manipulates.

The aims of the present study were to compare matching performance between ipsilateral and contralateral finger force matching tasks and to examine the effect of handedness on finger force perception. Eleven subjects were instructed to produce reference forces by an instructed finger (index-I or little-L finger) and to reproduce the same amount force by the same or a different finger within the hand (i.e., ipsilateral matching task), or by a finger of the other hand (i.e., contralateral matching task). The results of the ipsilateral and contralateral tasks in the present study commonly showed that (1) the reference and matching forces were matched closely when the two forces were produced by the same or homologous finger(s) such as I/I task; (2) the weaker little finger underestimated the magnitude of reference force of the index finger (I/L task), even with the higher level of effort (relative force), but the two forces were matched when considering total finger forces; (3) the stronger index finger closely matched the reference force of the little finger with the lower level of relative force (i.e., L/I task); (4) when considering the constant errors, I/L tasks showed an underestimation and L/I tasks showed an overestimation compared to I/I tasks. There was no handedness effect during ipsilateral tasks. During the contralateral task, the dominant hand overestimated the force of the non-dominant hand, while the non-dominant hand attempted to match the absolute force of the dominant hand. The overall results support the notion that the absolute, rather than relative, finger force is perceived and reproduced during ipsilateral and contralateral finger force matching tasks, indicating the uniqueness of finger force perception.

Introduction: Following lung transplantation, cytomegalovirus (CMV) has both direct and indirect adverse effects on the allograft. Natural killer cells mediate immune responses to CMV. This can be both dependent and independent of MHC class I expression. However, their role during CMV infection following lung transplantation is unknown. In this study, the immunophenotypic characteristics of NK cells were correlated with CMV infection following lung transplantation., Methods: Seventy lung transplant recipients were included in the study. NK cells were characterised via flow cytometric analysis of CD3, CD16, CD56, CD107a, CD107b, and CD161. CMV infection was determined using an established quantitative PCR technique on peripheral blood., Results: The number of peripheral blood NK cells with CD16, CD56 and CD161 phenotypes decreased in patients with CMV infection. However, there were no correlations between CMV infection and NK cell activation determined via LAMP expression., Conclusions: This study reports comparative differences in the peripheral blood NK cell repertoire in lung transplant recipients with CMV infection versus those without. However, NK cell activity did not alter with CMV infection, suggesting that CMV infection alone does not induce an NK cell response.

The purpose of the present study was to investigate the effect of intervening forces on the estimation of finger forces. To do this, we introduced intervening forces during a delayed force matching task. The basic idea in the present study was that when a reference force (or to-be-remembered force) is followed by another force, this second force (i.e., intervening force) will interfere with the estimation of the reference force. Subjects performed a modified delayed force matching task using the index finger of their dominant hand. This study consisted of eight experimental conditions which combined two reference forces (i.e., 10 and 30% MVCs) with four intervening forces (i.e., No, Half, Same and Double the reference force). The main finding of the present study was that the matching performance was systematically affected by intervening forces. The results showed that the reference force was underestimated in the condition where the intervening force was half the reference force, and overestimated in the condition where the intervening force was double the reference force. When the reference and intervening forces were the same, no intervening force effect was found. The effect of intervening force was explained by a distortion of force memory.

Background: Monocytes mediate immune responses following solid organ transplantation via cytokine secretion and differentiation to macrophage/dendritic cell lineages. To date, the pleiotropic immunomodulatory effect of statins on human monocytes following human heart transplantation has yet to be elucidated. This study was designed to assess the effects of statin administration on the monocyte repertoire., Methods: 108 patients were recruited into the study. Clinical data were collected from patients' notes. Peripheral blood immunophenotype was determined via flow cytometry (using CD11c, CD14, CD16, CD49d, CD64, CD80 and CD195)., Results: There were fewer circulating classical (p=0.0001) and non-classical (p=0.0013) monocytes in patients treated with a statin. CD64 expression was down-regulated (p=0.011 and p=0.049) whereas CD49d expression was up-regulated (p=0.004 and p=0.022) on classical and non-classical monocytes in this group. Patients receiving Atorvastatin had fewer circulating classical monocytes (p=0.001) compared to patients administered Pravastatin. Patients receiving Pravastatin had fewer circulating non-classical monocytes (p=0.029) compared to patients administered Atorvastatin., Discussion: Statin administration alters the circulating monocyte repertoire following heart transplantation, including population size, FcgammaRI and VLA-4 adhesion molecule expression. Furthermore, different statin treatments are associated with a selective depletion of macrophage or DC (re)generating monocytes.

Despite improvements in surgical technique, organ preservation, immunosuppression, and management of infection, the long term survival following lung transplantation remains low, mainly due to immune mediated complications such as acute and chronic rejection. Almost all immunosuppressive agents used in the prophylaxis and treatment of rejection following lung transplantation are targets of T cell maturation, function or proliferation, which in theory should cause sufficient disruption of the adaptive immune system to prevent graft rejection. However the five year survival rate of only 50% suggests this is not the case. More recent evidence suggests that NK cells may play a significant role in immune processes following lung transplantation. This article reviews the literature on the potential function of NK cells in rejection, infection, malignancy and tolerance following lung transplantation.

Background: Natural killer (NK) cells have the capacity to recognize and respond to alloantigen, yet their role in lung transplant rejection is not well defined. The aim of this study was to correlate NK cell numbers and immunophenotype in peripheral blood and tissue with graft function after lung transplantation., Methods: NK cell subsets were immunophenotyped in peripheral blood (n = 41). Lung tissue was stained for NK cells via CD16 and morphologic assessment (n = 30)., Results: Peripheral blood NK cells were activated in patients with chronic rejection, but the overall number of cells was lower in these patients when compared with stable patients. Furthermore, there was significantly more CD16(+) NK cells in the lung compartment of patients with bronchiolitis obliterans syndrome compared with stable patients (p = 0.001)., Conclusions: In patients with chronic rejection, peripheral blood NK cells are activated but their numbers decrease, while the number of NK cells in the lungs increases. This suggests NK cells systemically activate and migrate to the lung during the progression of chronic rejection after lung transplantation.

The effect of fatigue on finger force perception within a hand during ipsilateral finger force matching was examined. Thirteen subjects were instructed to match a reference force of an instructed finger using the same or different finger within the hand before and after index finger fatigue. Absolute reference force targets for the index or little finger were identical during pre- and post-fatigue sessions. Fatigue was induced by a 60-s sustained maximal voluntary contraction (MVC) of the index finger. Index finger MVC decreased approximately 29%, while there was a non-significant (about 5%) decrease in the little finger MVC. The results showed that: (1) the absolute reference and matching forces of the instructed fingers were not significantly changed after fatigue, while the total forces (sum of instructed and uninstructed finger forces) were increased after fatigue. (2) The relative forces (with respect to corresponding pre- and post-fatigue MVCs) of the index finger increased significantly in both reference and matching tasks, while the relative forces of the little finger remained unchanged after fatigue. (3) Matching errors remained unchanged after fatigue when the fatigued index finger produced the reference force, while the errors increased significantly when the fatigued index finger produced the matching force. (4) Enslaving (difference between total and instructed finger forces) increased significantly after fatigue, especially during force production by the fatigued index finger and when the little finger produced matching forces at higher force levels. (5) Enslaving significantly increased matching errors particularly after fatigue. Taken together, our results suggest that absolute finger forces within the hand are perceived within the CNS during ipsilateral finger force matching. Perception of absolute forces of the fatigued index finger is not altered after fatigue. The ability of the fatigued index finger to reproduce little finger forces is impaired to a certain degree, however. The impairment is likely to be attributable to altered afferent/efferent relationships of the fatigued index finger.

Myotonometric measurement of muscle compliance represents new technology that quantifies muscle tone. Compliance change during muscle contraction might provide an indirect measure of strength. The purpose of this study was to determine relationships among myotonometric measurements of muscle compliance, surface electromyographic (sEMG) measurements of muscle activation and joint force production during voluntary isometric knee extensions. The level of relationship will contribute to the construct validity of use of muscle compliance as an indirect strength measurement. Thirteen male subjects, mean age 25 +/- 1.5 years, participated. Simultaneous recordings of myotonometric, sEMG of the rectus femoris and isometric knee extension force measurements were taken at rest, during maximal voluntary contraction (MVC), and during 33% and 66% MVC contractions. Relationships among the three measurement procedures were calculated using correlation and regression analyses. Myotonometric measures of muscle compliance, sEMG and force measurements were highly correlated. Myotonometric measurements were best represented by a curvilinear (quadratic) relationship to sEMG (r = 0.82, p < 0.001) and joint force (r = 0.83, p < 0.001). The present experiments establish the construct validity of myotonometric measurements of muscle compliance as an indirect means of quantifying muscle strength and activation levels. This method, therefore, offers a possible alternative for cases in which direct measurement of joint force or sEMG is difficult or inappropriate.

Background: Lung transplantation (LTx) is widely accepted as a therapeutic option for end-stage respiratory failure in cystic fibrosis. However, airway complications remain a major cause of morbidity and mortality in these patients, serious airway complications like bronchopleural fistula (BPF) are rare, and their management is very difficult., Case Presentation: A 47-year-old man with end-stage respiratory failure due to cystic fibrosis underwent bilateral sequential lung transplantation. Severe post-operative bleeding occurred due to dense intrapleural adhesions of the native lungs. He was re-explored and packed leading to satisfactory haemostasis. He developed a bronchopleural fistula on the 14th post-operative day. The fistula was successfully repaired using pericardial and intercostal vascular flaps with veno-venous extracorporeal membrane oxygenator (VV-ECMO) support. Subsequently his recovery was uneventful., Conclusion: The combination of pedicled intercostal and pericardial flaps provide adequate vascular tissue for sealing a large BPF following LTx. Veno-venous ECMO allows a feasible bridge to recovery.

Background: Variations in the expression and activity levels of the multidrug-resistance MDR1/ABCB1 encoded P- glycoprotein (P-gp) have an impact on the therapeutic efficacy of many drugs. C3435T and G2677 polymorphisms of the MDR1/ABCB1 gene correlate with cellular expression levels of P-gp, a membrane-bound efflux pump which removes a multitude of drugs, including chemotherapy drugs and immunosuppressants, from cells. We aimed to investigate whether the phenomenon of drug resistance, mediated by the MDR1/ABCB1 gene and seen in tumor cells to chemotherapeutic agents, is important in the field of transplantation, predisposing some patients to resistance to immunosuppressants., Methods: G2677 and C3435T polymorphisms of the ABCB1 gene were determined by PCR in 170 heart transplant recipients. We examined the relationship between MDR1/ABCB1 polymorphisms and endomyocardial biopsy-proven rejection (EBPR) determined by biopsy performed at set intervals according to a standard protocol., Results: A significant relationship was found between a patient's C3435T genotype and freedom from first grade > or =3A rejection episode. 3435-CC recipients were 1.8 times (1.05-3.09; P = 0.03) more likely to undergo a > or =3A rejection episode in the first 12 months. Haplotypes derived from the G2677 and C3435T polymorphisms (GG/CC, GT/CT and TT/TT) amplified this phenomenon further (log rank, P = 0.03; HR 2.18; 1.21-4.26; P = 0.02)., Conclusions: ABCB1 polymorphisms correlate with freedom from grade > or =3A EBPR and we believe that this may be attributed to MDR1/ABCB1 encoded P-gp mediating the efflux of immunosuppressants out of leukocytes, with depleted immunosuppressant levels in leukocytes manifesting as increased cellular rejection.

The primary purpose was to examine the effect of enslaving on finger force perception during isometric finger force production using an ipsilateral force-matching paradigm. Fourteen subjects were instructed to produce varying levels of reference forces [10, 20, 30, and 40% maximal voluntary contraction (MVC)] force using one finger (index, I or little, L) and to reproduce these forces using the same finger (homo-finger tasks, I/I and L/L) or a different finger (hetero-finger tasks, I/L and L/I). Forces of all fingers were recorded. During homo-finger tasks, no differences were found in force magnitude or relative level of force (expressed as a proportion of MVC). The index finger matching force magnitudes were greater than the little finger reference force magnitudes, with significantly lower levels of relative force during L/I tasks; while the little finger matching forces underestimated the index finger reference forces with significantly higher levels of relative force during I/L tasks. The difference in the matching and reference forces by the instructed finger(s), i.e., matching error, was larger in hetero-finger tasks than in homo-finger tasks, particularly at high reference force levels (30, 40% MVC). When forces of all fingers were considered, enslaving (uninstructed finger forces) significantly minimized matching errors of the total force during both I/L and L/I hetero-finger tasks, especially at high reference force levels. Our results show that there is a tendency to match the absolute magnitude of the total force during ipsilateral finger force-matching tasks. This tendency is likely related to enslaving effects. Our results provide evidence that all (instructed and uninstructed) finger forces are sensed, thus resulting in perception of the absolute magnitude of total finger force.

Deficits in reciprocal inhibition likely contribute to excessive antagonist muscle cocontraction during voluntary movements of individuals with cerebral palsy. This study examined neural contributions to reciprocal inhibition of the soleus motoneurons of individuals with spastic, diplegic cerebral palsy and nondisabled individuals during various levels of voluntary tibialis anterior contraction. A condition-test H-reflex paradigm examined short- and long-latency contributions to reciprocal inhibition of soleus neural pools during changing levels of voluntary tibialis anterior contraction. Electrically induced short- and long-latency inhibition was similar between healthy, neurologically intact control subjects and subjects with cerebral palsy during rest. With increasing levels of tibialis anterior contraction, control subjects experienced increasing levels of soleus motoneuron inhibition, especially of long-latency inhibitory responses. In contrast, there was no evidence of modulation of short- or long-latency inhibition with increasing levels of tibialis anterior contraction among subjects with cerebral palsy. Deficits in long-latency (presynaptic) inhibition appear to contribute prominently to voluntary movement impairment of individuals with cerebral palsy.

Aims: ANGII mediates vascular neointimal formation through smooth muscle cell stimulation and enhanced production of growth factors leading to increased arterial medial layer thickness, which is a characteristic of transplant arteriosclerosis. ACE inhibition is known to be of benefit to patients with cardiovascular risk factors. We aimed to determine the effect of ACE inhibitor therapy on ACE enzymatic activity and serum ANGII levels following cardiac transplantation., Methods: A total of 43 serum samples from eight transplant recipients were used for analysis. Samples were taken monthly from the date of transplant for the initial 6 months. ANGII was measured using sandwich ELISA. ACE enzymatic activity was measured using spectrophotometric kinetic analysis., Results: There was a significant reduction in ACE enzymatic activity among individuals treated with ACE inhibitor therapy (18.0 +/- 16.6 vs 31.8 +/- 23.4, P = .008). We found significantly higher ANGII serum levels in patients receiving ACE inhibitor therapy compared to those not (2.4 +/- 2.1 vs 8.0 +/- 7.4, P = .002). There was also a significant positive correlation between ACE enzymatic activity and ANGII serum level (coefficient 0.332, P = .03)., Conclusions: Our results suggest an effective ACE independent pathway for ANGII conversion. Chymase can convert ANGI with higher affinity than ACE. Also, chymase is stored in mast cells, which infiltrate the myocardium following transplantation. This data indicate that pharmacological chymase inhibition may be a possible therapeutic strategy following transplantation.

Background: Chemokines regulate the recruitment and trafficking of leukocytes during an immune response. Animal models have shown correlations between chemokine production and leukocyte infiltration during allograft rejection. Also, antagonism of chemokine receptors in transplant models has produced prolonged graft survival. Individuals homozygous for a 32 base pair deletion in the CC chemokine receptor 5 (CCR5) gene have an inactive receptor. Renal transplant recipients homozygous for the deletion have been shown to survive significantly longer than those heterozygous or homozygous for the wild type allele. CCR5 ligands are upregulated during allograft rejection aiding infiltration of leukocytes. We investigated the influence of CCR5Delta32 polymorphism on outcome following human cardiac transplantation., Methods: Recipients and corresponding donors were genotyped for CCR5Delta32 polymorphism using polymerase chain reactions., Results: We found no correlation between recipient genotype and outcome following transplantation. However, there was a significant correlation between donor genotype and mortality in patients transplanted for a nonischemic condition (DD = n/a, ID = 4%, II = 25%, P = .0014)., Conclusions: The induction of CCR5 expression in endomyocardial biopsy tissue is known to correlate with leukocyte graft infiltration. We suggest that donor CCR5 may be more important for leukocyte trafficking during rejection than recipient CCR5 expression. The CCR5 gene is highly conserved, and due to the small population available for this study, more work is required from other centers.

Introduction: Survival following lung transplantation is less than 50% at 5 years, mainly due to immune-mediated chronic rejection. Recently a novel subset of T cells, CD4-veCD8-ve CD30+ve, so-called double negative (DN) CD30+ve T cells, has been described and shown to be responsible for tolerance in an animal model of skin transplantation., Methods: We investigated 18 lung transplant recipients for the presence of DN CD30+ve T cells in resting peripheral blood and also following in vitro stimulation of recipient peripheral blood mononuclear cells (PBMCs) with donor spleen cells., Results: Small percentages (0.2% to 6%) of DN T cells are detectable in resting PBMCs of human transplant patients (n = 18), but these did not correlate with allograft function, acute rejection episodes, HLA mismatch, or CMV status. On repeated stimulation of recipient PBMCs (two exposures) in vitro by donor spleen cells (2:1 ratio stimulators to responders) the percentage of DN CD30+ve T cells within the lymphocyte pool correlated with preservation of allograft lung function (both for FEV(1), P = .009, and FEF(25-75), P = .036) and was inversely correlated with grade of chronic rejection. On repeated exposure of recipient PBMCs to donor spleen cells with a 1:1 ratio the percentage of DN CD30+ve T cells correlated with the number of acute rejection episodes of grade 2 or greater. The total number of HLA mismatches correlated with the percentage DN CD30+ve T cells present after primary stimulation of recipient PBMCs with donor spleen cells (1:1 ratio). The number of mismatches at the B locus inversely correlated with the percentage of DN CD30+ve T cells after primary stimulation of recipient PBMCs with donor spleen cells (1:1 ratio; P = .031, n = 18)., Conclusion: Percentages of DN CD30+ve T cells present following repeated stimulation of recipient PBMCs by donor spleen cells correlated with preservation of graft function following lung transplantation.

Background: The angiotensin converting enzyme insertion deletion polymorphism (ACE I/D) has been associated with much cardiovascular pathology, including posttransplantation hypertension. Hypertension is a significant cause of morbidity and mortality after cardiac transplantation. We investigated the influence of the ACE I/D polymorphism on posttransplantation hypertension., Methods: A total of 211 heart transplant recipients and 154 corresponding donors were genotyped for the ACE I/D polymorphism by polymerase chain reaction. ACE enzymatic activity was measured by spectrophotometric kinetic analysis. Sitting systolic and diastolic blood pressures were recorded at 3 consecutive visits, and the mean was calculated. Clinical data, including demographics and medication, were collected for all recipients. Results were analyzed by the chi-square test and analysis of variance, taking a p value of <0.05 to be significant., Results: A total of 41.7% of the subjects were hypertensive (diastolic blood pressure >90 mm Hg) at the time of the study, with 79.6% taking at least one antihypertensive agent. We found no difference between the number of antihypertensive agents, cyclosporin dose and level, renal function, or systolic blood pressure for the different recipient or donor genotypes. We also found no significant correlation between ACE enzymatic activity and systolic or diastolic blood pressure., Conclusions: Our study of 211 recipients and 154 corresponding donors is the largest investigation of this polymorphism in a cardiac transplantation population. We found no apparent relationship between the ACE genotype (of either donor or recipient) and systemic hypertension (absolute measurements and the number or dose of antihypertensive agents used).

Bronchiolitis obliterans syndrome is a clinical diagnosis based on lung function parameters. Using induced sputum, taken from lung transplant recipients, this paper reports on the correlation between the neutrophil count and the percentage change from postoperative baseline for FEV(1), FEF(50), and FEF(25-75). In double lung transplant recipients the correlations were significant for FEV(1) (r = -0.68, p = 0.002), FEF(50) (r = -0.65, p = 0.016), and FEF(25-75) (r = -0.56, p = 0.016). In single lung transplant recipients, no significant correlations were seen.

Objectives: Muscle stiffness increases during muscle contraction. The purpose of this study was to determine the strength of the correlation between myotonometric measurements of muscle stiffness and surface electromyography (sEMG) measurements during various levels of voluntary isometric contractions of the biceps brachii muscle., Subjects: Eight subjects (four female; four male), with mean age of 30.6 +/- 8.23, volunteered to participate in this study., Methods: Myotonometer and sEMG measurements were taken simultaneously from the right biceps brachii muscle. Data were obtained: (1) at rest, (2) while the subject held a 15 lb (6.8 kg) weight isometrically and, (3) during a maximal voluntary isometric contraction. Myotonometer force-displacement curves (amount of tissue displacement to a given unit of force applied perpendicular to the muscle) were compared with sEMG measurements using Pearson's product-moment correlation coefficients., Results: Myotonometer and sEMG measurement correlations ranged from -0.70 to -0.90. The strongest correlations to sEMG were from Myotonometer force measurements between 1.00 and 2.00 kg., Conclusions: Myotonometer and sEMG measurements were highly correlated. Tissue stiffness, as measured by the Myotonometer, appears capable of assessing changes in muscle activation levels.

Background: Due to the increasing demand for suitable cardiac donor organs, acceptance criteria need to be re-evaluated. We retrospectively analyzed the effect of donor age on survival following cardiac transplantation., Method: Three hundred thirty-five cardiac transplant recipients and corresponding donor data were reviewed using SPSS., Results: Seventy-two recipients had early posttransplant angiography or postmortem data available. The mean donor age of recipients with evidence of graft coronary artery disease (32.5 +/- 11.7 years) was significantly higher than that of recipients free of transplant coronary artery disease (TCAD) (24.8 +/- 9.4 years; P=.003). Recipient of organs from donors aged less than 50 years were less likely to develop TCAD than those of donors aged over 50 years (odds ratio 0.333; 95% CI 0.239-0.465; P=.044). TCAD also occurred much earlier posttransplantation in recipients of organ from donors over 50 years (mean time 6.5 years; median 5.0 years) than those of donors under 50 years (mean time 12.7 years; median 14.0 years)., Conclusion: We observed no increase in mortality associated with cardiac donors over 50 years. However, increased donor age was associated with an increased incidence of TCAD.

The purposes of this study were to assess intra- and interrater reliabilities by novice users of the Myotonometer (Neurogenic Technologies, Inc., Missoula, MT), a portable electronic device that quantifies muscle tone (stiffness) and paresis, in assessing children with cerebral palsy. Two raters used the Myotonometer to assess the biceps brachii and medial gastrocnemius muscles of 10 children with spastic-type cerebral palsy. Muscles were measured in a relaxed state and during a voluntary isometric contraction. Intraclass correlation coefficients and repeatability coefficients were calculated for each muscle and for each condition (relaxed and contracted). Intrarater reliabilities ranged from 0.82 to 0.99 (biceps brachii muscles) and 0.88 to 0.99 (medial gastrocnemius muscles). Interrater reliabilities ranged from 0.74 to 0.99 (biceps brachii muscles) and 0.84 to 0.99 (medial gastrocnemius muscles). Repeatability coefficients indicated a 98% level of agreement between raters across all conditions. Novice users of the Myotonometer, with few exceptions, had high to very high intra- and interrater reliabilities for measurements of the biceps brachii and medial gastrocnemius muscles of children with spastic-type cerebral palsy.

Objectives: To assess the intra- and interrater reliabilities of the Myotonometer, a hand-held, computerized, electronic device that quantifies muscle stiffness (tone/compliance)., Design: Reliability study., Setting: Research laboratory., Participants: Thirty-five healthy, nondisabled adults (age range, 22-42 y)., Interventions: Not applicable., Main Outcome Measures: Two raters used the Myotonometer to evaluate subjects' lateral gastrocnemius and biceps brachii muscles. Muscles were measured in a relaxed state and during a voluntary isometric contraction. Coefficients were calculated for each muscle and each condition (relaxed, contracted). Results were analyzed by using Design II intraclass correlation coefficients., Results: Reliability coefficients were highest when the instrument exerted moderate to strong forces against the muscle (range, 0.50-2.00 kg; intrarater reliability R range, .84 - .99; interrater reliability R range, .75 - .96)., Conclusions: Myotonometer measurements had high to very high intra- and interrater reliabilities for measurements of the lateral gastrocnemius and biceps brachii muscles.

The current treatment of obliterative bronchiolitis in lung transplant recipients is sub-optimal. Triptolide is a novel immunosuppressant that has a mechanism of action distinct from currently available immunosuppressants, including induction of T-cell apoptosis, blockade of fibroblast proliferation/maturation and inhibition of transforming growth factor-beta (TGF-beta) mRNA production. We hypothesized that triptolide may be helpful in blocking obliterative airway disease in lung transplant recipients. We investigated the effect of PG490-88, a water-soluble derivative of triptolide, in a mouse heterotopic tracheal allograft model of obliterative airway disease. We show that PG490-88 attenuates airway obliteration in this model and inhibits accumulation of inflammatory cells, and therefore may have preventive or therapeutic benefits for patients with obliterative airway disease (OAD) following lung transplantation.