An Anaesthesiology and Emergency Medicine Multidisciplinary Simulation-Based Bootcamp

Aim The fundamental concept of multidisciplinary education is a shared mental model that leads to better interdependent collaboration. The aim of this bootcamp was to create a sustainable induction curriculum for Anaesthesiology and Emergency Medicine trainees and nurses through training in a simulated multidisciplinary environment. Methods The two-day bootcamp consisted of lectures, equipment demonstration, workshops, and high-fidelity simulated scenarios. A pre- and post-course MCQ test was used for assessment of knowledge acquisition. Pre and post confidence scores were used to evaluate procedural skill confidence level. A 5-point Likert scale was used to evaluate qualitative feedback from participants. Results Seven anaesthesiology trainees, two anaesthetic nurses, six emergency medicine trainees and three emergency medicine nurses were enrolled. There was a statistically significant increase (p-value<0.01) in post-MCQ scores, portraying significant knowledge acquisition. The total procedural confidence scores increased from 375 (±9.15) to 550 (±8.43), (p < 0.01). All participants agreed that the stated educational objectives were met and relevant to their clinical practice, and strongly commended team training exercises. Conclusion Multidisciplinary simulation-based training improves team performance as well as transfer of knowledge across two or more disciplines. Overlapped training between Anaesthesiology and Emergency Medicine created an opportunity for sharing of educational resources in the current time-based speciality training system.

Expanding the Menu of HIV Prevention Options: A Qualitative Study of Experiences with Long-Acting Injectable Cabotegravir as PrEP in the Context of a Phase II Trial in the United States.

Adherence challenges with oral pre-exposure prophylaxis have stimulated interest in alternate modes of administration including long-acting injections. We conducted 30 in-depth interviews with 26 male trial participants and 4 clinical providers in a Phase IIa study (ÉCLAIR) evaluating the use of long-acting cabotegravir (CAB-LA) injections in New York and San Francisco. Interviews exploring attitudes and experiences with CAB-LA were audiotaped, transcribed, and analyzed using thematic content analysis. Despite a high frequency of some level of side effects, almost all participants reported being interested in continuing with CAB-LA, versus a daily oral, due to its convenience and the perceived advantage of not worrying about adhering to pills. Providers reinforced the importance of CAB-LA as a prevention option and the need for guidelines to assist patient decision-making. Further research is needed on the acceptability of CAB-LA among men and women at higher risk for HIV in different settings.

Follow-up arrangements for breast cancer patients; is it appropriate to transfer surveillance to general practitioners?

The aim of this study was to examine the evidence for hospital follow up of breast cancer survivors and to identify patient preferences for hospital or community follow-up. We surveyed General Practitioner attitudes towards community follow-up and quantified the incidence of new or recurrent cancers within a patient cohort to identify their primary symptoms and thus cancer detection in the community. A 22 item questionnaire was distributed to 101 breast cancer survivors from a cohort of 921 treated patients. A 9 item questionnaire was distributed to 81 General Practitioners. Patients are reassured by hospital outpatient appointments, n=63 (74%) but have high levels of confidence in General Practitioner follow-up, n=57 (67%). General Practitioners are equally divided regarding their support for the transfer of follow-up (51%, 49%). Ten of the 14 new cancer episodes were associated with obvious clinical signs (p < 0.05). The proposed transfer of follow-up for patients to general practice by the national cancer control programme is appropriate.

Discussing childbearing with HIV-infected women of reproductive age in clinical care: a comparison of Brazil and the US.

Despite long term access to highly active antiretroviral therapy in Brazil and the US, little is known about women's communication with their HIV provider regarding childbearing or the unmet need for reproductive counseling. We utilized identical survey questions to collect data from HIV-infected women of reproductive age in Rio de Janeiro (n = 180) and Baltimore (n = 181). We conducted univariate analyses to compare findings between samples of women and multivariate logistic regression to determine factors associated with childbearing desires, childbearing intentions, and provider communication among the combined sample of women (n = 361). Over one-third of women in Rio de Janeiro and nearly one-half of women in Baltimore reported the desire for future childbearing. Nevertheless, the majority of women in clinical care had not discussed future childbearing with their HIV provider. Even in countries with an advanced approach to HIV care, we found low and inadequate communication between providers and female patients about childbearing.

Outcome of laparoscopic duodenal switch for morbid obesity.

BACKGROUND: The aim of this study was to determine the safety and efficacy of laparoscopic duodenal switch (LDS) as a treatment option in a selected group of patients with morbid obesity. METHODS: This retrospective analysis of a prospective database assessed the frequency of all complications and alterations in weight, body mass index (BMI), co-morbidity and quality of life. RESULTS: One hundred and twenty-one patients underwent LDS between April 2003 and March 2009. Median preoperative weight was 160 kg and median BMI 55 kg/m(2). All procedures were performed laparoscopically. The in-hospital mortality rate was zero. No ileoduodenal anastomotic stenosis was encountered. There were four clinical leaks (3·3 per cent) managed by laparoscopic drainage and placement of a feeding jejunostomy. Median percentage excess weight loss was 75 per cent at 12 months and 90 per cent at 24 months. Thirty-six of 40 diabetic patients had complete resolution of diabetes within 1 year. There were significant improvements in other obesity-related co-morbidity. Only a few patients developed postoperative protein deficiency, and fat-soluble vitamin deficiencies were easily managed with oral supplementation. CONCLUSION: The LDS procedure is a safe and effective treatment for morbid obesity and its associated co-morbidity in selected patients.

Effects of transcutaneous electrical nerve stimulation and therapeutic exercise on quadriceps activation in people with tibiofemoral osteoarthritis.

STUDY DESIGN: Blinded, randomized controlled trial. OBJECTIVES: To determine if the combination of transcutaneous electrical nerve stimulation (TENS) set to a sensory level and therapeutic exercise would be more effective than the combination of placebo TENS and therapeutic exercises or therapeutic exercises only to increase quadriceps activation in individuals with tibiofemoral osteoarthritis. BACKGROUND: Quadriceps activation deficits are common in those with tibiofemoral osteoarthritis, and TENS has been reported to immediately increase quadriceps activation. Yet the long-term benefits of TENS for motor neuron activation have yet to be determined. METHODS: Thirty-six individuals with radiographically assessed tibiofemoral osteoarthritis were randomly assigned to the TENS and exercise, placebo and exercise, and exercise only groups. All participants completed a supervised 4-week lower extremity exercise program. TENS and placebo TENS were worn throughout the therapeutic exercise sessions, as well as during daily activities. Our primary outcome measures, quadriceps central activation ratio, and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were evaluated at baseline and at 2 weeks and 4 weeks of the intervention. RESULTS: Quadriceps activation was significantly higher in the TENS with exercise group compared to the exercise only group at 2 weeks (0.94 ± 0.04 versus 0.82 ± 0.12, P<.05) and the placebo and exercise group at 4 weeks (0.94 ± 0.06 versus 0.81 ± 0.15, P<.05). WOMAC scores improved in all 3 groups over time, with no significant differences among groups. CONCLUSION: This study provides evidence that TENS applied in conjunction with therapeutic exercise and daily activities increases quadriceps activation in patients with tibiofemoral osteoarthritis and, while function improved for all participants, effects were greatest in the group treated with a combination of TENS and therapeutic exercises. LEVEL OF EVIDENCE: Therapy, level 1b-.

In humans the adiponectin receptor R2 is expressed predominantly in adipose tissue and linked to the adipose tissue expression of MMIF-1.

In this study, the regional adipose tissue-adiponectin (AT-ADN) and adiponectin receptor (R1 and R2) expression and their relation with metabolic parameters, circulating and AT-derived cytokine expressions were compared. Paired subcutaneous adipose tissue (SCAT) and visceral adipose tissue (VAT) were taken from 18 lean and 39 obese humans, AT-mRNA expression of adipokines analysed by RT-PCR and corresponding serum levels by enzyme-linked immunosorbent assay (ELISA). R1 and R2 adipocyte expression was compared with 17 other human tissues. ADN-gene expression was lower in VAT than SCAT [mean (SD) 1.54 (1.1) vs. 2.84 (0.87); p < 0.001], and lower in obese subjects (VAT : p = 0.01;SCAT : p < 0.001). SCAT-ADN correlated positively with serum ADN (r = 0.33;p = 0.036) but not VAT-ADN. AT expressions of ADN and macrophage migration inhibiting factor (MMIF), IL18 and cluster of differentiation factor 14 (CD14) in both depots showed inverse correlations. R1 and R2 were expressed ubiquitously and R2 highest in SCAT, and this is much higher (x100) than R1 (x100). R expression was similar in lean and obese subjects and unrelated to the metabolic syndrome, however, receptors correlated with VAT-MMIF (R 1: r = 0.4;p = 0.008;R 2: r = 0.35,p = 0.02) and SCAT-MMIF expression (R 2: r = 0.43;p = 0.004). Unlike ADN, its receptors are expressed in many human tissues. Human R2 expression is not highest in the liver but in AT where it is associated with MMIF expression. The adiponectin-dependent insulin-sensitizing action of thiazolidinediones is thus probably to differ amongst species with weaker effects on the human liver.

Establishment of an HIV/sexually transmitted disease programme and prevalence of infection among incarcerated men in Jamaica.

The goal of this study is to describe the establishment of an HIV testing and treatment programme in the Jamaican correctional system and to estimate the prevalence of HIV/sexually transmitted disease (STD) among adult incarcerated men in this country. A demonstration project was implemented by the Jamaican Department of Correctional Services and Ministry of Health in the nation's largest correctional centre. All inmates were offered HIV and syphilis testing, and a subset was offered chlamydia, gonorrhoea and trichomoniasis testing. Cross-sectional data from the project were reviewed to determine the prevalence and correlates of HIV/STD. HIV test acceptance was 63% for voluntary testers (n = 1200). The prevalence of HIV was 3.3% (95% confidence interval [CI] 2.33-4.64) (n = 1017) and the prevalence syphilis was 0.7% (95% CI 0.29-1.49) (n = 967). Among the subset tested (n = 396) the prevalence of chlamydia was 2.5% (95% CI 1.22-4.49) and for trichomoniasis it was 1.8% (95% CI 0.01-3.60), but no cases of gonorrhoea were detected (n = 396). The prevalence of HIV was significantly higher at 25% (95% CI 13.64-39.60) for persons located in a separate section where individuals labelled as men who have sex with men (MSM) are separated. HIV/STD testing is important and feasible in Jamaica. A special focus should be placed on providing services to inmates labelled as MSM. Other Caribbean nations may also benefit from similar programmes.

Effects of disinhibitory transcutaneous electrical nerve stimulation and therapeutic exercise on sagittal plane peak knee kinematics and kinetics in people with knee osteoarthritis during gait: a randomized controlled trial.

OBJECTIVE: to determine whether sensory transcutaneous electrical nerve stimulation (TENS) augmented with therapeutic exercise and worn for daily activities for four weeks would alter peak gait kinetics and kinematics, compared with placebo electrical stimulation and exercise, and exercise only. DESIGN: randomized controlled trial. SETTING: motion analysis laboratory. SUBJECTS: thirty-six participants with radiographically assessed knee osteoarthritis and volitional quadriceps activation below 90% were randomly assigned to electrical stimulation, placebo and comparison (exercise-only) groups. INTERVENTIONS: participants in all three groups completed a four-week quadriceps strengthening programme directed by an experienced rehabilitation clinician. Active electrical stimulation units and placebo units were worn in the electrical stimulation and placebo groups throughout the rehabilitation sessions as well as during all activities of daily living. MAIN MEASURES: peak external knee flexion moment and angle during stance phase were analysed at a comfortable walking speed before and after the intervention. FINDINGS: Comfortable walking speed increased for all groups over time (TENS 1.16 ± 0.15 versus 1.32 ± 0.16 m/s; placebo 1.21 ± 0.34 versus 1.3 ± 0.24 m/s; comparison 1.27 ± 0.18 versus 1.5 ± 0.14 m/s), yet no group differences in speed were found. No differences were found for peak flexion moment or angle between groups overtime. CONCLUSIONS: TENS in conjunction with therapeutic exercise does not seem to affect peak flexion moment and angle during stance over a four-week period in participants with tibiofemoral osteoarthritis.

Effects of balance training on gait parameters in patients with chronic ankle instability: a randomized controlled trial.

OBJECTIVE: To examine the effects of a four-week balance training programme on ankle kinematics during walking and jogging in those with chronic ankle instability. A secondary objective was to evaluate the effect of balance training on the mechanical properties of the lateral ligaments in those with chronic ankle instability. DESIGN: Randomized controlled trial. SETTING: Laboratory. SUBJECTS/PATIENTS: Twenty-nine participants (12 males, 17 females) with self-reported chronic ankle instability were randomly assigned to a balance training group or a control group. INTERVENTION: Four weeks of supervised rehabilitation that emphasized dynamic balance stabilization in single-limb stance. The control group received no intervention. MAIN OUTCOME MEASURES: Kinematic measures of rearfoot inversion/eversion, shank rotation, and the coupling relationship between these two segments throughout the gait cycle during walking and jogging on a treadmill. Instrumented ankle arthrometer measures were taken to assess anterior drawer and inversion talar tilt laxity and stiffness. RESULTS: No significant alterations in the inversion/eversion or shank rotation kinematics were found during walking and jogging after balance training. There was, however, a significant decrease in the shank/rearfoot coupling variability during walking as measured by deviation phase after balance training (balance training posttest: 13.1 degrees +/- 6.2 degrees , balance training pretest: 16.2 degrees +/- 3.3 degrees , P = 0.03), indicating improved shank/rearfoot coupling stability. The control group did not significantly change. (posttest: 16.30 degrees +/- 4.4 degrees , pretest: 18.6 degrees +/- 7.1 degrees , P40.05) There were no significant changes in laxity measures for either group. CONCLUSIONS: Balance training significantly altered the relationship between shank rotation and rearfoot inversion/eversion in those with chronic ankle instability.

Differences in static and dynamic measures in evaluation of talonavicular mobility in gait.

STUDY DESIGN: Controlled laboratory study using a cross-sectional design. OBJECTIVES: To compare the measurements of navicular drop during walking and running to those made clinically during a static position in a group of healthy young adults. BACKGROUND: The navicular drop test is a common clinical measure of foot structure and, more specifically, of talonavicular joint function. Previous work has focused on static measurement to establish the relationship between navicular drop and various overuse injuries. However, loads on foot structure are dramatically increased during gait. Examining navicular drop dynamically is more reflective of the functional demands of the foot when walking and running. METHODS: The navicular drop of 72 healthy runners was evaluated using 2 static methods. Results were used to classify individuals into groups and compared to dynamic measures of navicular drop made during walking and running. Three-dimensional motion capture and an instrumented treadmill were used to assess dynamic navicular mobility. A repeated-measures analysis of variance (ANOVA) was performed to examine differences between measurement conditions. Between-group differences were assessed with independent-samples t test (P<.05). RESULTS: Static measures of navicular drop were not found to be uniformly predictive of dynamic function during walking or running. Functional navicular drop measurements underestimated the dynamic measures in all foot types, while subtalar neutral drop overestimated dynamic measures for individuals with neutral and hypermobile foot types. No differences in navicular drop were found between foot types during walking, and small differences were found in running only between the hypomobile and hypermobile foot types. Maximum foot deformation during gait occurs at the time of maximum ground reaction force. Significant differences in navicular drop between foot type groups measured statically become muted when looking at group differences while walking and running. CONCLUSIONS: Differences in navicular mobility between foot type groups during walking and running indicate that factors other than static alignment affect dynamic foot mobility. Dynamic assessment of navicular mobility may be an effective tool to examine the interplay of how the extrinsic force demands of gait and intrinsic structure and neuromuscular control affect foot function in walking and running.

Social cohesion, condom use, and sexually transmitted infections among female sex workers living with HIV in the Dominican Republic.

This cross-sectional study examines the relationship between social cohesion with consistent condom use (CCU) and sexually transmitted infections (STIs) among the Abriendo Puertas (Opening Doors) cohort of female sex workers (FSWs) living with human immunodeficiency virus (HIV) in the Dominican Republic (n = 228). Using data from the follow-up survey of the cohort, we conducted multivariate logistic regression to explore these dynamics. Social cohesion was significantly associated with CCU between FSWs living with HIV and their clients in the last month (adjusted odds ratio [AOR] = 1.65, 95% confidence interval [CI]: 1.11-2.45) and STI prevalence among FSWs (AOR: 3.76, CI: 1.159-12.162). Social cohesion was not associated with CCU between FSWs living with HIV and their steady partners. However, both illicit drug use in the past six months (AOR = 0.11, CI: 0.023-0.57) and pregnancy intentions (AOR = 0.11; CI: 0.02-0.42) were significantly associated with CCU with steady partners. Findings highlight the differential role of social cohesion on condom use outcomes between FSWs living with HIV and their paying clients versus steady partners. Research on the pathways via which cohesion influences condom use among sex workers and their clients is merited, as is research regarding the role of drug use and pregnancy intentions on condom use with steady partners.

Retrospective cohort study of 925 OAGB procedures. The UK MGB/OAGB collaborative group.

BACKGROUND: Mini-One Anastomosis Gastric Bypass is a new operation that provides comparable outcomes to the common bariatric procedures. Revisional surgery is still needed after a number of MGB-OAGB procedures. The aim of this study is to report the causes and management of these revisions. METHODS: From 2010 to 2018, 925 MGB-OAGB operations were performed at 7 bariatric units across the United Kingdom and included in this retrospective cohort study. The data was retrospectively collected and analysed. The primary end point was the identification of the causes and management of revisions. Follow up ranged from 6 months to 3 years. RESULTS: Twenty-two patients [2.3%] required revisional surgery after MGB-OAGB. Five patients [0.5%] developed severe diarrhoea managed by shortening the bilio-pancreatic limb to 150 cm. Four patients [0.4%] developed afferent loop syndrome and bile reflux was reported in another 3 [0.3%] cases; all were managed by either conversion to Roux en Y Gastric Bypass or a Braun anastomosis. Postoperative bleeding was controlled laparoscopically in 3 patients [0.3%]. Liver decompensation that was reported in 2 patients [0.2%] was treated by shortening the BPL in one patient and a reversal to normal anatomy in another. The liver failure resolved in both patients. Other indications for revision included two gastro-jejunal stenosis [0.2%], one perforated ulcer [0.1%], one patient [0.1%] with excessive weight loss and one case [0.1%] of protein malnutrition. None of the 22 patients undergoing revisional surgery after MGB-OAGB died. Lost to follow up rate was 0.2%. CONCLUSION: Complications requiring revisional surgery after MGB-OAGB are uncommon [2.3%] and the majority can be managed by bilio-pancreatic limb shortening, the addition of a Braun side-to-side anastomosis or conversion to RYGB. Bilio-pancreatic limb length of 200 cm or more resulted in serious complications of liver failure, protein malnutrition, excessive weight loss and diarrhoea.

Plasma obestatin levels are lower in obese and post-gastrectomy subjects, but do not change in response to a meal.

OBJECTIVE: To investigate a potential role for obestatin in humans by examining response to a fixed energy meal. CONTEXT: A new anorectic peptide hormone, obestatin has recently been isolated from rat stomach. The significance of this peptide in humans is unknown. STUDY DESIGN: Case-control study. SETTING: Hospital-based study. PATIENTS: Nine healthy controls, nine morbidly obese subjects and eight post-gastrectomy subjects. INTERVENTION: Subjects attended after an overnight fast and were given a fixed energy meal (1550 kJ). MAIN OUTCOME MEASURE: The response of obestatin to a meal in the different groups. RESULTS: Fasting obestatin was significantly lower in obese subjects as compared to lean subjects (27.8+/-4 vs 17.2+/-2 pg/ml, P=0.03). Obestatin was also decreased in gastrectomy subjects but this did not reach statistical significance (27.8+/-4 vs 21.9+/-3 pg/ml, P=0.3). Obestatin did not change significantly from baseline in response to the meal. Lean and obese subjects had a similar obestatin/ghrelin ratio (0.04+/-0.003 vs 0.05+/-0.009, P=0.32), but this was higher in the gastrectomy group (0.04+/-0.003 vs 0.1+/-0.01, P<0.001). CONCLUSIONS: Obestatin does not vary significantly with a fixed energy meal, but is significantly lower in morbidly obese subjects as compared to lean subjects supporting a possible role for obestatin in long-term body weight regulation. Obestatin tended to be lower in gastrectomy subjects and their obestatin/ghrelin ratio differed from healthy controls. Hence, the expression of obestatin is altered following gastrectomy, suggesting other sites outside the stomach may also secrete obestatin.

The influence of arch supports on knee torques relevant to knee osteoarthritis.

PURPOSE: Changes in footwear and foot orthotic devices have been shown to significantly alter knee joint torques thought to be relevant to the progression if not the development of knee osteoarthritis (OA) in the medial tibiofemoral compartment. The purpose of this study was to determine if commonly prescribed arch support cushions promote a medial force bias during gait similar to medial-wedged orthotics, thereby increasing knee varus torque during both walking and running. METHODS: Twenty-two healthy, physically active young adults (age, 29.2 +/- 5.1 yr) were analyzed at their self-selected walking and running speeds in control shoes with and without arch support cushions. Three-dimensional motion capture data were collected in synchrony with ground reaction force (GRF) data collected from an instrumented treadmill. Peak external knee varus torque during walking and running were calculated through a full inverse dynamic model and compared. RESULTS: Peak knee varus torque was statistically significantly increased by 6% (0.01 +/- 0.02 N.m.(kg.m)(-1)) in late stance during walking and by 4% (0.03 +/- 0.03 N.m.(kg.m)(-1)) during running with the addition of arch support cushions. CONCLUSIONS: The addition of material under the medial aspect of the foot by way of a flexible arch support promotes a medial force bias during walking and running, significantly increasing knee varus torque. These findings suggest that discretion be employed with regard to the prescription of commonly available orthotic insoles like arch support cushions.

A kinematics and kinetic comparison of overground and treadmill running.

PURPOSE: The purpose of this study was to compare the kinematic and kinetic parameters of treadmill running to those of overground running. METHODS: Twenty healthy young subjects ran overground at their self-selected moderate running speed. Motion capture and ground reaction force (GRF) data for three strides of each limb were recorded and the subjects' average running speed was evaluated. The subjects then ran on an instrumented treadmill set to their average overground running speed while motion capture and GRF data were recorded. The kinematics (body segment orientations and joint angles) and kinetics (net joint moments and joint powers) for treadmill (15 consecutive gait cycles) and overground running (three cycles each limb) were calculated and compared. RESULTS: The features of the kinematic and kinetic trajectories of treadmill gait were similar to those of overground gait. Statistically significant differences in knee kinematics,the peak values of GRF, joint moment, and joint power trajectories were identified. DISCUSSION: Parameters measured with an adequate instrumented treadmill are comparable to but not directly equivalent to those measured for overground running. With such an instrument, it is possible to study the mechanics of running under well-controlled and reproducible conditions. SIGNIFICANCE: Treadmill-based analysis of running mechanics can be generalized to overground running mechanics, provided the treadmill surface is sufficiently stiff and belt speed is adequately regulated.

Gait synchronized force modulation during the stance period of one limb achieved by an active partial body weight support system.

Our purpose was to demonstrate the ability of an actively controlled partial body weight support (PBWS) system to provide gait synchronized support during the stance period of a single lower extremity while examining the affect of such a support condition on gait asymmetry. Using an instrumented treadmill and a motion capture system, we compared gait parameters of twelve healthy elderly subjects (age 65-80 years) during unsupported walking to those while walking with 20% body weight support provided during only the stance period of the right limb. Specifically, we examined peak three-dimensional ground reaction force (GRF) data and the symmetry of lower extremity sagittal plane joint angles and of time and distance parameters. A reduction in all three GRF components was observed for the supported limb during modulated support. Reductions observed in the vertical GRF were comparable to the desired 20% support level. Additionally, GRF components examined for the unsupported limb during modulated support were consistently similar to those measured during unsupported walking. Modulated support caused statistically significant increases in asymmetry for knee flexion during stance (increased 5.9%), hip flexion during late swing (increased 9.1%), and the duration of single limb support (increased 2.8%). However, the observed increases were similar or considerably less than the natural variability in the asymmetry of these parameters during unsupported walking. The ability of the active PBWS device to provide unilateral support may offer new and possibly improved applications of PBWS rehabilitation for patients with unilateral walking deficits such as hemiparesis or orthopaedic injury.

Lack of an acute effect of ghrelin on markers of bone turnover in healthy controls and post-gastrectomy subjects.

BACKGROUND: Ghrelin is a gut-brain peptide that powerfully stimulates appetite and growth hormone secretion and is also known to directly regulate osteoblast cell function in vitro and in animal models. Little is known about the effects of ghrelin on bone turnover in humans. As the stomach is the main site of ghrelin synthesis, gastrectomy patients are deficient in ghrelin; they are also prone to osteopenia and osteomalacia. HYPOTHESIS: Ghrelin may play a role in bone regulation in humans; ghrelin deficiency following gastrectomy is associated with the disrupted regulation of bone turnover seen in these subjects. SUBJECTS AND METHODS: In a randomised, double-blind, placebo-controlled study 8 healthy controls and 8 post-gastrectomy subjects were infused with intravenous ghrelin (5 pmol/kg/min) or saline over 240 min on different days. Subjects were given a fixed energy meal during the infusion. Ghrelin, GH, type-1 collagen beta C-telopeptide (betaCTX), a marker of bone resorption, and procollagen type-1 amino-terminal propeptide (P1NP), a marker of bone formation, were measured. RESULTS: Fasting ghrelin was significantly lower in the gastrectomy group during the saline infusion (226.1+/-62.0 vs. 762+/-71.1 ng/l p<0.001). Growth hormone was significantly higher at 90 min after the ghrelin infusion, compared to saline in both healthy controls (61.1+/-8.8 vs. 1.4+/-0.6 mIU/l p<0.001) and gastrectomy subjects (61.1+/-11.8 vs. 0.9+/-0.2 mIU/l p<0.001) confirming the ghrelin was bioactive. Gastrectomy subjects were significantly older and had significantly higher plasma betaCTX than healthy controls at all time points (ANOVA p=0.009). After adjustment for age and BMI ghrelin was found to be a significant predictor of baseline plasma betaCTX and was inversely correlated with baseline plasma betaCTX (beta=-0.54 p=0.03 R2=26%). However, there was no significant effect of the ghrelin infusion on plasma betaCTX or P1NP in either subject group. CONCLUSIONS: Ghrelin infusion has no acute effect on markers of bone turnover in healthy controls and post-gastrectomy subjects, but is inversely correlated with bone resorption.

Physiological modulation of gait variables by an active partial body weight support system.

Partial body weight support (PBWS) systems used for rehabilitation status post-neurological and musculoskeletal pathologies and injuries are traditionally passive. Our purpose was to demonstrate the ability of an actively controlled PBWS system to provide a clinically relevant modulated support condition while investigating the impact of such a condition on the dynamics of gait. Using an instrumented treadmill and a motion capture system, we compared gait parameters of six healthy young adults (age 24-31 years) during unsupported walking to those under the assistance of two support conditions (a constant 20% body weight support, and a modulated support providing 20% body weight support during the loading response of each leg while allowing for an unsupported terminal stance). The modulated condition achieved support synchronized to gait cycle events with mean and maximum loading errors at the 20% body weight support level equal to 1.01 and 2.44 kg, respectively. Constant support significantly reduced sagittal plane hip angle range of motion and increased ankle platarflexion as compared to unsupported walking (p < 0.05). Also, a clear trend of decreased stride length was observed for constant support. No significant differences in these parameters were evident between the modulated support condition and unsupported walking. Ankle power generation and absorption both significantly decreased under constant support. The modulated support condition significantly increased ankle power absorption though showed no change in ankle power generation. The ability of the presented active PBWS device to provide individualized support schemes may offer new and possibly improved applications of PBWS rehabilitation.

Determinants of gait as applied to children with cerebral palsy.

In the present study, we quantified the isolated contributions of eight determinants of gait on the vertical center of mass (CoM) displacement of both typically developing children and children with cerebral palsy (CP). The role of these determinants, on vertical excursion, has never been examined for children or children with CP. We hypothesized that the relative contributions of the determinants to vertical CoM excursion of children with CP would be the same as the age-matched controls. We found that based on the similarities in the determinants effect on gait between the controls and adults reflect that children of this age walk with a mature gait. When applied to subjects with CP the determinant analysis found similar, but slightly exaggerated effects of those of the controls. All determinants that negatively affect CoM excursion were significantly worse in the children with CP, while those determinants that decreased excursion were varied. Heel rise, single support knee flexion, and pelvic obliquity had similar effects for on both groups. Pelvic rotation resulted in more excursion reduction in the controls, while leg inclination was more beneficial in reducing the CP groups excursion. The main cause for increased vertical excursion of the CoM in the children with CP was the increased knee flexion of both legs during double support. This excessive lowering of the CoM means that extra work is done to raise the CoM over the single support leg. The situation is aggravated by the fact that the CoM was lifted higher than typical because of the heel lifting during single support. Although these determinants allow quantification of the effects of gait kinematics and provide some useful information for gait they are limited in their ability to quantify the dynamics and kinetics of gait that are important for individuals with walking disabilities.