Weight-bearing exercise accuracy influences muscle activation strategies of the knee.

Purpose: Dynamic stability of the knee joint is a research topicof increasing focus after ACL injury, stroke, and incomplete spinal cord injury. Since rehabilitation programs use functional weightbearing tasks to improve neuromuscular control of the knee, it is important to understand the adaptability of muscle control strategies during weight-bearing exercise. The purpose of this study was to compare muscle activation patterns during a single leg squat (SLS) exercise performed before and after feedback-controlled training.

Mathematical models of human paralyzed muscle after long-term training.

Spinal cord injury (SCI) results in major musculoskeletal adaptations, including muscle atrophy, faster contractile properties, increased fatigability, and bone loss. The use of functional electrical stimulation (FES) provides a method to prevent paralyzed muscle adaptations in order to sustain force-generating capacity. Mathematical muscle models may be able to predict optimal activation strategies during FES, however muscle properties further adapt with long-term training.

Musculoskeletal adaptations in chronic spinal cord injury: effects of long-term soleus electrical stimulation training.

Objective: The purpose of this study was to determine whether long-term electrical stimulation training of the paralyzed soleus could change this muscle's physiological properties (torque, fatigue index, potentiation index, torque-time integral) and increase tibia bone mineral density.

Methods: Four men with chronic (>2 years) complete spinal cord injury (SCI; American Spinal Injury Association classification A) trained 1 soleus muscle using an isometric plantar flexion electrical stimulation protocol. The untrained limb served as a within-subject control.

Training of staff for the delivery of PET/CT services in the UK.

Evidence for the cost effectiveness of PET/CT imaging is now driving the widespread introduction of PET/CT services throughout the UK. The provision of PET/CT facilities will require a workforce of medical, scientific, technical and engineering staff who are adequately trained and fit for purpose. Suitably trained staff in this speciality are scarce.

Measuring the quality of diabetes care in urban and rural Indian health programs.

Objective: The purpose of this study was to compare the quality of diabetes care provided to American Indians/Alaska Natives (AI/AN) by urban and rural Indian health programs.

Design: Medical record review data collected by the Indian Health Service as part of the Diabetes Care and Outcomes Audit in 2002.

Setting: Seventeen urban Indian health clinics and 225 rural Indian health programs.

Peripheral quantitative computed tomography: measurement sensitivity in persons with and without spinal cord injury.

Objectives: To determine (1) the error attributable to external tibia-length measurements by using peripheral quantitative computed tomography (pQCT) and (2) the effect these errors have on scan location and tibia trabecular bone mineral density (BMD) after spinal cord injury (SCI).

Design: Blinded comparison and criterion standard in matched cohorts.

Setting: Primary care university hospital.

The value of registration correction in the attenuation correction of myocardial SPECT studies using low resolution computed tomography images.

Background: Artifacts caused by tissue attenuation create problems in the interpretation of myocardial perfusion studies. In a previous study we evaluated attenuation correction using 'Hawkeye' and noted that the incidence of anterior/apical defects increased after attenuation correction. This increased incidence appeared to be associated with mis-registration between emission and transmission images.

Feedback-controlled stimulation enhances human paralyzed muscle performance.

Chronically paralyzed muscle requires extensive training before it can deliver a therapeutic dose of repetitive stress to the musculoskeletal system. Neuromuscular electrical stimulation, under feedback control, may subvert the effects of fatigue, yielding more rapid and extensive adaptations to training. The purposes of this investigation were to 1) compare the effectiveness of torque feedback-controlled (FDBCK) electrical stimulation with classic open-loop constant-frequency (CONST) stimulation, and 2) ascertain which of three stimulation strategies best maintains soleus torque during repetitive stimulation.

High dry bean intake and reduced risk of advanced colorectal adenoma recurrence among participants in the polyp prevention trial.

Adequate fruit and vegetable intake was suggested to protect against colorectal cancer and colorectal adenomas; however, several recent prospective studies reported no association. We examined the association between fruits and vegetables and adenomatous polyp recurrence in the Polyp Prevention Trial (PPT). The PPT was a low-fat, high-fiber, high-fruit, and vegetable dietary intervention trial of adenoma recurrence, in which there were no differences in the rate of adenoma recurrence in participants in the intervention and control arms of the trial.

Phrenic neuropathy due to neuralgic amyotrophy.

The authors reviewed the medical records of 33 patients diagnosed with idiopathic phrenic neuropathy and found that 17 patients had clinical features of neuralgic amyotrophy. They concluded that a careful clinical and electrodiagnostic evaluation may implicate neuralgic amyotrophy as a causative disease in patients with apparently isolated phrenic neuropathy.

Predictive model of muscle fatigue after spinal cord injury in humans.

The fatigability of paralyzed muscle limits its ability to deliver physiological loads to paralyzed extremities during repetitive electrical stimulation. The purposes of this study were to determine the reliability of measuring paralyzed muscle fatigue and to develop a model to predict the temporal changes in muscle fatigue that occur after spinal cord injury (SCI). Thirty-four subjects underwent soleus fatigue testing with a modified Burke electrical stimulation fatigue protocol.

Postfatigue potentiation of the paralyzed soleus muscle: evidence for adaptation with long-term electrical stimulation training.

Understanding the torque output behavior of paralyzed muscle has important implications for the use of functional neuromuscular electrical stimulation systems. Postfatigue potentiation is an augmentation of peak muscle torque during repetitive activation after a fatigue protocol. The purposes of this study were 1) to quantify postfatigue potentiation in the acutely and chronically paralyzed soleus and 2) to determine the effect of long-term soleus electrical stimulation training on the potentiation characteristics of recently paralyzed soleus muscle.

Electrically induced muscle contractions influence bone density decline after spinal cord injury.

Study Design: Longitudinal repeated-measures; within-subject control.

Objective: We examined the extent to which an isometric plantar flexion training protocol attenuates bone loss longitudinally after SCI.

Summary Of Background Data: After spinal cord injury (SCI), bone mineral density (BMD) of paralyzed extremities rapidly declines, likely because of loss of mechanical loading of bone via muscle contractions.

Musculoskeletal plasticity after acute spinal cord injury: effects of long-term neuromuscular electrical stimulation training.

Maintaining the physiologic integrity of paralyzed limbs may be critical for those with spinal cord injury (SCI) to be viable candidates for a future cure. No long-term intervention has been tested to attempt to prevent the severe musculoskeletal deterioration that occurs after SCI. The purposes of this study were to determine whether a long-term neuromuscular electrical stimulation training program can preserve the physiological properties of the plantar flexor muscles (peak torque, fatigue index, torque-time integral, and contractile speed) as well as influence distal tibia trabecular bone mineral density (BMD).

Assessment of physical function and secondary complications after complete spinal cord injury.

Purpose: Two physical function questions on the widely used SF-12 Health Related Quality of Life questionnaire appear less than optimal for people with complete spinal cord injury (SCI). Physical function questions typically receive the lowest score unless the individual is ambulatory. Additionally, the influence of secondary complications of SCI on quality of life is largely unknown.

Predicting human chronically paralyzed muscle force: a comparison of three mathematical models.

Chronic spinal cord injury (SCI) induces detrimental musculoskeletal adaptations that adversely affect health status, ranging from muscle paralysis and skin ulcerations to osteoporosis. SCI rehabilitative efforts may increasingly focus on preserving the integrity of paralyzed extremities to maximize health quality using electrical stimulation for isometric training and/or functional activities. Subject-specific mathematical muscle models could prove valuable for predicting the forces necessary to achieve therapeutic loading conditions in individuals with paralyzed limbs.

Bone mineral density after spinal cord injury: a reliable method for knee measurement.

Objectives: To test the interrater reliability of a standardized method to analyze knee bone mineral density (BMD) using dual-energy x-ray absorptiometry (DXA); to compare spine, hip, and knee BMD of people with spinal cord injury (SCI) with able-bodied controls; and to determine the relation between hip BMD and knee BMD in SCI and able-bodied subjects.

Design: Criterion standard and masked comparison.

Setting: Primary care university hospital.

Idiopathic pulmonary artery aneurysm.

A case of idiopathic pulmonary artery aneurysm is presented along with a review of our experience of this rare condition. These entities may have an association with cystic medial degeneration of the arterial wall and are subject to the same complications as aortic aneurysms.

Sustained muscle activity minimally influences dynamic position sense of the ankle.

Study Design: Cross-sectional study.

Objective: The purpose of this study was to determine if a sustained fatiguing contraction of the dorsiflexor muscles alters the dynamic position sense (proprioception) and the associated central nervous system processing time of information from the ankle.

Background: Ankle injury has been hypothesized to be related to altered proprioception as a consequence of fatiguing exercise.

Inhibition of insulin-like growth factor-I receptor (IGF-IR) signaling and tumor cell growth by a fully human neutralizing anti-IGF-IR antibody.

Insulin-like growth factor-I receptor (IGF-IR) plays an important role in tumor cell growth and survival. On ligand stimulation, IGF-IR, a receptor tyrosine kinase, phosphorylates tyrosine residues on two major substrates, IRS-1 and Shc, which subsequently signal through the Ras/mitogen-activated protein kinase and phosphatidylinositol 3-kinase/AKT pathways. Here, we describe the characterization of a fully human anti-IGF-IR monoclonal antibody 19D12 that inhibits IGF binding and autophosphorylation of both IGF-IR/IGF-IR homodimers and IGF-IR/insulin receptor heterodimers.

Effects of a maximal graded exercise test on glutathione as a marker of acute oxidative stress.

Purpose: Strenuous exercise in animal studies has been shown to cause acute oxidative stress due to the generation of oxygen-centered free radicals reflected in lower levels of glutathione (GSH), higher levels of glutathione disulfide (GSSG), and a drop in GSH:GSSG ratios, the maintenance of which is crucial for a variety of cell functions. Human studies on this topic are limited. The purpose of this study was to investigate the effects of a maximal graded exercise test GXTmax (modified Bruce protocol) on GSH as a marker of acute oxidative stress, and whether full recovery will occur at 60 minutes postexercise.