Liana functional assembly along the hydrological gradient in Central Amazonia.

Soil hydrology, nutrient availability, and forest disturbance determine the variation of tropical tree species composition locally. However, most habitat filtering is explained by tree species' hydraulic traits along the hydrological gradient. We asked whether these patterns apply to lianas. At the community level, we investigated whether hydrological gradient, soil fertility, and forest disturbance explain liana species composition and whether liana species-environment relationships are mediated by leaf and stem wood functional traits. We sampled liana species composition in 18 1-ha plots across a 64 km2 landscape in Central Amazonia and measured eleven leaf and stem wood traits across 115 liana species in 2000 individuals. We correlated liana species composition, summarized using PCoA with the functional composition summarized using principal coordinate analysis (PCA), employing species mean values of traits at the plot level. We tested the relationship between ordination axes and environmental gradients. Liana species composition was highly correlated with functional composition. Taxonomic (PCoA) and functional (PCA) compositions were strongly associated with the hydrological gradient, with a slight influence from forest disturbance on functional composition. Species in valley areas had larger stomata size and higher proportions of self-supporting xylem than in plateaus. Liana species on plateaus invest more in fast-growing leaves (higher SLA), although they show a higher wood density. Our study reveals that lianas use different functional solutions in dealing with each end of the hydrological gradient and that the relationships among habitat preferences and traits explain lianas species distributions less directly than previously found in trees.

Spatiotemporal patterns in the natural and anthropogenic additions to the soundscape in parts of the Salish Sea, British Columbia, 2018-2020.

Passive acoustic recorders were deployed over two years (February 2018-March 2020) in the Salish Sea to monitor the underwater soundscape. Seasonal cycles and differences between the open Strait of Juan de Fuca and protected inner waterways were pervasive during this period. A comparison between natural and human-derived noise demonstrated the impact of anthropogenic activities on the sound field. Elevated ambient noise levels during winter resulted predominantly from greater sea states and storm events. Abiotic additions were defined through correlations to wind speed, wave and precipitation measures. Vessel noise was a pervasive anthropogenic addition; commercial vessel noise was consistently present, whereas smaller vessels showed weekly and diurnal patterns, especially during the summer when their presence increased. A better understanding of the different soundscape constituents, and when each dominates, is crucial to understanding the human impact on underwater ecosystems and the organisms within them, leading to more effective mitigation measures.

A new role for stereolithic models in the management of complex mandibular fractures.

The author discusses a new role for stereolithic models in the management of complex mandibular fractures with reference to two case studies.

Successful use of a military-grade haemostatic agent for a major head and neck bleed.

BACKGROUND: Major haemorrhage is a catastrophic complication occurring in 3-4 per cent of head and neck cancer patients. Massive haemorrhage also causes 50 per cent of preventable deaths in combat situations. There has been a surge of interest in the development of effective haemostatic products in the military, with chitosan being one such product. CASE REPORT: A 48-year-old lady presented with a life-threatening head and neck bleed. She was known to have a malignant peripheral nerve sheath sarcoma originating from the left parapharyngeal space. Bleeding was successfully controlled with the application of Celox™ granules, a chitosan-based product currently used in the military. CONCLUSION: This paper describes the first known use of a military haemostatic agent to control a malignant head and neck bleed. Celox granules can be poured directly onto a wound to enhance haemorrhage control. The suggested mechanism of action and reports of current uses of haemostatic agents are described.

Hoist the mainsail! The use of standardised colour-coded sloops to aid vascular control in head and neck surgery.

The authors have adopted a set pattern of colour coded vascular sloops that they use to identify and isolate vital structures in the head and neck. This simple and cost-effective technique aids vascular control and has applications in elective head and neck surgery, as well as in controlling haemorrhage secondary to trauma.

Fibrous myopathy as a complication of repeated intramuscular injections for chronic headache.

Two cases of fibrous myopathy associated with repeated, long-term intramuscular injections for treatment of chronic temporomandibular joint pain and chronic headache, respectively, are described. Both patients developed severe, function-limiting contractures in upper and lower extremity muscles used as injection sites. In one of the cases, the contractures were painful. Electrophysiological testing, magnetic resonance imaging and muscle biopsy results were all consistent with myopathy and replacement of skeletal muscle with noncontractile fibrous tissue. These cases are presented to increase awareness of fibrous myopathy and to promote surveillance for this serious potential complication of long-term intramuscular injections in chronic headache and other pain patients.

A confidential study of deaths after emergency medical admission: issues relating to quality of care.

In this retrospective pilot study we examine the feasibility of establishing a confidential enquiry into why some patients die after emergency admission to hospital. After excluding those who died in the first hour or who were admitted for palliative care, pairs of physicians were able to collect quantitative and qualitative data on 200 consecutive deaths. Both physicians reported shortfalls of care in 14 patients and one of the pair in 25 patients whose deaths would not have been the expected outcome. In 25, the shortfalls of care may have contributed to their deaths. Major problems were delays in seeing doctors, inaccurate diagnoses, delays in investigations and initiation of treatment. They occurred mostly in those admitted at night. It is possible that establishing the correct diagnosis and starting appropriate treatment may have been delayed in 64% of the 200 patients. The headline figures appear worse than some previous external assessment studies but this study did concentrate on those in whom problems were more likely. Nevertheless, the frequency is too high to be overlooked. In this feasibility study we have demonstrated that it is practicable for local staff to collect and assess data in hospitals and that the types of problems identified are relevant to anyone planning how to organise emergency care. A larger definitive study should be performed.

Improved glucose tolerance and insulin sensitivity after electrical stimulation-assisted cycling in people with spinal cord injury.

DESIGN: Longitudinal training. OBJECTIVES: The purpose was to determine the effect of electrical stimulation (ES)-assisted cycling (30 min/day, 3 days/week for 8 weeks) on glucose tolerance and insulin sensitivity in people with spinal cord injury (SCI). SETTING: The Steadward Centre, Alberta, Canada. METHODS: Seven participants with motor complete SCI (five males and two females aged 30 to 53 years, injured 3-40 years, C5-T10) underwent 2-h oral glucose tolerance tests (OGTT, n=7) and hyperglycaemic clamp tests (n=3) before and after 8 weeks of training with ES-assisted cycling. RESULTS: Results indicated that subjects' glucose level were significantly lower at 2 h OGTT following 8 weeks of training (122.4+/-10 vs 139.9+/-16, P=0.014). Two-hour hyperglycaemic clamps tests showed improvement in all three people for glucose utilisation and in two of three people for insulin sensitivity. CONCLUSIONS: These results suggested that exercise with ES-assisted cycling is beneficial for the prevention and treatment of Type 2 diabetes mellitus in people with SCI. SPONSORSHIP: Supported by Alberta Paraplegic Foundation, Therapeutic Alliance.

Infrared skin temperature measurement cannot be used to detect myofascial tender spots.

OBJECTIVE: To determine the relationship between skin temperature and pressure tolerance in patients with myofascial pain. DESIGN: Blinded, criterion standard. SETTING: Community physiatry clinic. PATIENTS: Sixteen consecutive female patients with myofascial pain or fibromyalgia with shoulder girdle symptoms above the T4 level for at least 3 months. No patient met the exclusion criteria of recent trauma to the area or therapy within 48 hours. INTERVENTIONS: Skin temperature was measured by using a hand-held infrared thermometer over 36 points arranged in a grid on the upper and midtrapezius. Pressure threshold was then assessed at each point by using a pressure threshold meter. A second, blinded examiner then examined each patient to find any myofascial tender spots and noted within which square on the grid they occurred. MAIN OUTCOME MEASURES: The correlation between temperature and pressure threshold and the temperature differences between tender and nontender areas. RESULTS: A nonsignificant correlation of.023 (p =.57) was found between temperature and pressure threshold. The mean temperature of the tender spots was 32.1 degrees C. No significant difference existed between tender spot temperature and temperature of nontender points (32.1 degrees C, p =.653) or contralateral points (32 degrees C, p =.893). CONCLUSIONS: Skin temperature, measured with a hand-held infrared thermometer, cannot be used to diagnose and follow treatment progress of myofascial tender spots, because skin temperature over tender spots does not correlate with pressure sensitivity.

Habitat-related error in estimating temperatures from leaf margins in a humid tropical forest.

Leaf margin characters are strong predictors of mean annual temperature (MAT) in modern plant communities and widely used tools for reconstructing paleoclimates from fossil floras. However, the frequency of nonentire-margined species may vary dramatically between different habitats of the same forest. In this paper we explore the potential for this habitat variation to introduce error into temperature reconstructions, based on field data from a modern lowland forest in Amazonian Ecuador.The data show that the provenance of leaves can influence temperature estimates to an important degree and in a consistent direction. Woody plants growing along lakes and rivers underestimated MAT by 2.5°-5°C, while those in closed-canopy forest provided very accurate predictions. The high proportion of liana species with toothed leaves in lakeside and riverside samples appears to be responsible for a large part of the bias. Samples from closed-canopy forest that included both lianas and trees, however, were more accurate than tree-only or liana-only samples.We conclude that paleotemperature reconstructions based on leaf margin characters will be misleading to the extent that fossilization provides a better record of certain habitats than others. The preponderance of lake and river deposits in the angiosperm fossil record suggests that underestimation of mean annual paleotemperature may be common.

Quadriceps muscle deoxygenation during functional electrical stimulation in adults with spinal cord injury.

STUDY DESIGN: Cross-sectional study comparing healthy subjects with age and gender matched subjects with spinal cord injury (SCI, injury levels from C5 to T12). OBJECTIVES: To compare the acute cardiorespiratory responses and muscle oxygenation trends during functional electrical stimulation (FES) cycle exercise and recovery in the SCI and healthy subjects exercising on a mechanical cycle ergometer. SETTING: Seven volunteers in each group participated in one exercise test at the Rick Hansen Center, University of Alberta, Edmonton, Canada. METHODS: Both groups completed a stagewise incremental test to voluntary fatigue followed by 2 min each of active and passive recovery. Cardiorespiratory responses were continuously monitored using an automated metabolic cart and a wireless heart rate monitor. Tissue absorbency, an index of muscle oxygenation, was monitored non-invasively from the vastus lateralis using near infrared spectroscopy. RESULTS: The healthy subjects showed significant (P<0.05) increases in the oxygen uptake (VO2), heart rate (HR) and ventilation rate (VE) from rest to maximal exercise. The SCI subjects showed a twofold increase in VO2 (P>0.05), a threefold increase in VE (P<0.05) and a 5 beats/min increase in HR (P>0.05) from the resting value. The SCI subjects demonstrated a lesser degree (P<0.05) of muscle deoxygenation than the healthy subjects during the transition from rest to exercise. Regression analysis indicated that the rate of decline in muscle deoxygenation with respect to the VO2 was significantly (P<0.05) faster in the SCI subjects compared to healthy subjects. CONCLUSIONS: FES exercise in SCI subjects elicits: (a) modest increases in the cardiorespiratory responses when compared to resting levels; (b) lower degree of muscle deoxygenation during maximal exercise, and (c) faster changes in muscle deoxygenation with respect to the VO2 during exercise when compared to healthy subjects.

Preliminary outcome analysis of a long-term rehabilitation program for severe acquired brain injury.

OBJECTIVES: To describe the general characteristics and functional outcomes of individuals treated in a publicly funded, long-term, acquired brain injury rehabilitation program and investigate variables affecting functional outcomes in this patient population. DESIGN: Retrospective database review of demographic, descriptive, and functional outcome assessment data. SETTING: Publicly funded, comprehensive, multidisciplinary, long-term, residential brain injury rehabilitation program in Alberta, Canada (64 beds). PATIENTS: All rehabilitation patients admitted to and discharged from the brain injury program from February 1991 to March 1999 (n = 349). INTERVENTIONS: Multidisciplinary rehabilitation program. MAIN OUTCOME MEASURES: Demographic and descriptive information included sex, age at admission, type and severity of injury, time from injury to long-term program admission, and length of stay (LOS). Functional outcome information included level of care required at admission and discharge, admission and discharge Rappaport disability rating scale scores, and admission and discharge FIM instrument and Functional Assessment Measure scores for a subset of patients. RESULTS: Fifty-nine percent of the subjects had severe traumatic brain injuries (TBI) and 41% had severe nontraumatic brain injuries (NTBI) of various causes. Mean age at admission was older and LOS was longer for NTBI compared with TBI; there were no other differences between the groups in demographic or descriptive measures. The TBI group had significantly lower admission motor subscale scores than the NTBI group, but the groups did not differ on cognitive scores. All functional assessment measures showed statistically significant improvement from admission to discharge, and 85.6% of patients were discharged to community living after a mean LOS of 359.5 days. Functional status at admission, age at admission, length of time between injury and admission, and LOS in the rehabilitation program significantly correlated with functional improvement. CONCLUSIONS: Patients with severe TBI and NTBI who were not candidates for other more conventional forms of rehabilitation showed significant improvement in functional outcomes after extended program admissions. Consideration was also given to the potential insensitivity of commonly used outcome assessment measures in this population.

Effect of concurrent strength and endurance training on skeletal muscle properties and hormone concentrations in humans.

The purpose of this study was to investigate the effect of concurrent strength and endurance training on strength, endurance, endocrine status and muscle fibre properties. A total of 45 male and female subjects were randomly assigned to one of four groups; strength training only (S), endurance training only (E), concurrent strength and endurance training (SE), or a control group (C). Groups S and E trained 3 days a week and the SE group trained 6 days a week for 12 weeks. Tests were made before and after 6 and 12 weeks of training. There was a similar increase in maximal oxygen consumption (VO2max) in both groups E and SE (P < 0.05). Leg press and knee extension one repetition maximum (1 RM) was increased in groups S and SE (P < 0.05) but the gains in knee extension 1 RM were greater for group S compared to all other groups (P < 0.05). Types I and II muscle fibre area increased after 6 and 12 weeks of strength training and after 12 weeks of combined training in type II fibres only (P < 0.05). Groups SE and E had an increase in succinate dehydrogenase activity and group E had a decrease in adenosine triphosphatase after 12 weeks of training (P < 0.05). A significant increase in capillary per fibre ratio was noted after 12 weeks of training in group SE. No changes were observed in testosterone, human growth hormone or sex hormone binding globulin concentrations for any group but there was a greater urinary cortisol concentration in the women of group SE and decrease in the men of group E after 12 weeks of training (P < 0.05). These findings would support the contention that combined strength and endurance training can suppress some of the adaptations to strength training and augment some aspects of capillarization in skeletal muscle.

Functional electrical stimulation effect on orthostatic hypotension after spinal cord injury.

OBJECTIVE: To investigate the possibility of using functional electrical stimulation (FES) to control orthostatic hypotension in patients with spinal cord injury (SCI) and to clarify the mechanism of the response. DESIGN: Subjects were tilted by 10 degree increments with varying intensities of lower-extremity FES. Stimulation over muscles was compared to stimulation over noncontractile sites. SETTING: Physical therapy department of a major rehabilitation center. PATIENTS: Six patients with SCI above T6 (3 with recent injury recruited consecutively from an inpatient spinal cord rehabilitation unit, and 3 from the community with longstanding injury, recruited as volunteers). MAIN OUTCOME MEASURES: Blood pressure, heart rate, and perceived presyncope score recorded at each tilt angle and analyzed using a multivariate analysis of variance statistical methodology. RESULTS: Systolic and diastolic blood pressure increased with increasing stimulation intensities (systolic, p = .001; diastolic, p = .0019) and decreased with increasing angle of tilt (p < .001) regardless of the site of stimulation. Subjects tolerated higher angles of incline with electrical stimulation than without (p = .03). CONCLUSIONS: FES causes a dose-dependent increase in blood pressure independent of stimulation site that may be useful in treating orthostatic hypotension.

The effect of polytrauma in persons with traumatic spine injury. A prospective database of spine fractures.

STUDY DESIGN: A mixed cross-sectional survey and cohort study using a prospectively gathered database of persons with traumatic spine injury. OBJECTIVES: To identify demographic and injury mechanism factors that predict greater injury severity, and to determine the effect of injury severity on outcomes in traumatic spine fracture. SUMMARY OF BACKGROUND DATA: Traumatic spine fracture outcome studies have focused on defining type and level of vertebral fracture without considering the severity of associated injuries. In the trauma population, greater injury severity has been shown to be related to worse outcome. No studies have been reported on the effect of injury severity on outcome in the traumatic spine fracture population. METHODS: Prospectively collected data on 830 persons with traumatic spine injury who were admitted to a trauma hospital were reviewed. Patient demographics; injury mechanism; hospital events; and disability, employment, and pain status at discharge, 1 year, and 2 years after injury were recorded. Associations between these factors and trauma severity (Injury Severity Score) were explored using Pearson's correlation and analysis of variance. RESULTS: Trauma was more severe in patients who had been married previously, who were involved in a motor vehicle accident, were ejected from the vehicle, had loss of consciousness, had higher-level and multiple complicated vertebral fractures, or had neurologic deficit. Those more severely injured had longer lengths of stay, more surgery, more complications, higher mortality, more disability, and less return to work. CONCLUSIONS: Persons with traumatic spine injury and polytrauma have poorer short- and long-term outcomes. This high-risk group may require aggressive interventions, more hospital resources, and close follow-up observation after discharge from hospital to optimize outcome.

Functional electrical stimulation exercise increases GLUT-1 and GLUT-4 in paralyzed skeletal muscle.

The study purpose was to determine the effect of functional electrical stimulation (FES)-leg cycle ergometer training (30 minutes on 3 d/wk for 8 weeks) on the GLUT-1 and GLUT-4 content of paralyzed skeletal muscle. Biopsy samples of vastus lateralis muscle were obtained pre- and post-training from five individuals with motor-complete spinal cord injury ([SCI] four men and one woman aged 31 to 50 years, 3 to 25 years postinjury involving C5-T8). Western blot analysis indicated that GLUT-1 increased by 52% and GLUT-4 increased by 72% with training (P < .05). This coincided with an increase in the muscle oxidative capacity as indicated by a 56% increase in citrate synthase (CS) activity (P < .05) and an improvement in the insulin sensitivity index as determined from oral glucose tolerance tests (P < .05). It is concluded that FES endurance training is effective to increase glucose transporter protein levels in paralyzed skeletal muscle of individuals with SCI.