Abbreviation use decreases effective clinical communication and can compromise patient safety

Clear communication is paramount for achieving the safest and best patient outcomes, for maximising time efficiency, and lowering clinician workload. Multiple factors contribute to communication efficacy, including knowledge of topics between those communicating, interpersonal familiarity, and available time. Information exchange is growing faster and more frequent due to evolving communication technology, and communication is expanding as a response to increasing workloads. The number of referrals between specialties and the general practitioner (GP) is rising. The use of abbreviations has expanded in clinical communications and is likely to lead to misunderstanding, increased workload, and worse patient outcomes. In this article, we explore the use of abbreviations in the clinical setting.

Caffeine: benefits and drawbacks for technical performance

Surgical and minimally-invasive procedures, including cardiac and radiological, have high-stake patient outcomes. Working pressures, altering shift rotas, and ever-increasing demands have led to worsening sleep patterns for surgeons and allied professionals. Sleep deprivation alone has harmful consequences in relation to clinical outcomes and the physical and mental health of the surgeon, and to offset fatigue, some surgeons use legal stimulants such as caffeine and energy drinks. This stimulant use, however, may come at the cost of negative effects on cognitive and physical function. We aimed to explore evidence behind the use of caffeine, and its consequences on technical performance and clinical outcomes.

911 Delayed Presentation of a Re-Bleed from A Traumatic Splenic Artery Rupture Following Endovascular Management in A Patient with Median Arcuate Ligament Syndrome

Endovascular management of splenic blunt trauma is widely accepted as a safe and effective alternative to open surgery in carefully selected patients. Following a radiologically successful intervention, patients are normally discharged with no follow up after 48-72 hours of haemodynamic stability and satisfactory serial haemoglobin levels.

We present a case of a fit and well 24-year-old male patient who presented with abdominal pain, syncope and haemodynamic instability 14 days post successful splenic artery coil-embolization for splenic artery aneurysm rupture secondary to blunt trauma. After initial resuscitation, computed tomography angiography was performed and demonstrated active bleeding from the splenic artery aneurysm which was deemed likely to be a consequence of retrograde filling. The patient underwent successful emergency re-embolization using a combination of embolization coils and Onyx via a trans-splenic approach to eliminate retrograde flow. On further review of the imaging, it was incidentally noted there was evidence suggesting a diagnosis of median arcuate ligament syndrome, which may have predisposed the patient to splanchnic artery aneurysm formation.

This case report highlights a potential limitation of endovascular management compared to open surgery and summarises the literature surrounding splenic artery anatomical variations and the implications of median arcuate ligament syndrome. A re-bleed following embolization is a hostile prospect with potentially catastrophic outcomes for patients if not recognised quickly. The authors propose that interval re-imaging should be considered following endovascular management of blunt splenic trauma.

493 An Examination into The Impact of Sleep Deprivation on Surgeons

Background

Lack of sleep amongst surgeons is significant and worrying. It poses short- and long-term risks to surgeons’ health and negatively impacts patient outcomes. Previous studies have examined sleep deprivation amongst health care professionals. The aim of the present study was to examine impact in a specific population of surgical doctors.

Method

A questionnaire-based study completed in the anatomy department of King’s College London University. Surgical subjects spanned the United Kingdom. Subjects completed 14 questions regarding sleep habits. Data was compiled, calculating a sleep deprivation score.

Results

Valid responses were obtained from 66 surgical subjects of varying seniority. Mean age of subjects was 33.7 years old. 59.1% of subjects had rota commitments changing on a weekly basis. Average sleep amongst subjects amounted to 6.15 (± 1.26) hours per night. Daily sleep did not present differences dependent on seniority level (p = 0.186). 25.8% of subjects took >30 minutes to fall asleep. Our subjects woke 1.67 (± 1.21) times a night. Mean sleep deprivation score amongst our surgical population was 16.5 (± 4.26) demonstrating moderate negative impact on daily activities. 28.9% accumulated ≧20 sleep deprivation score demonstrating severe impact of sleep deprivation on life.

Conclusions

Our study has demonstrated reduced quantity and quality of sleep amongst our subject population. With protecting the health of both patients and surgeons in mind, we must place higher importance on improving sleep amongst surgical professionals.

Infective endocarditis in patients who use IV drugs: a single centre cohort

Background

Managing endocarditis in intravenous drug use (IVDU) patients is challenging: unless patients successfully quit IVDU, the risk of re-infection is high. Clinicians often raise concerns with ethical and resource allocation principles when considering valve replacement surgery in this patient population. To help inform practice, we sought to determine the long-term outcomes of IVDU patients with endocarditis who underwent valve surgery in our center.

Method

After research ethics board approval, infective endocarditis cases managed surgically at our General Hospital between 2009 and 2018 were identified through the Cardiac Care Network. We reviewed patients' charts and included those with a history of IVDU in this study. We abstracted data on baseline characteristics, peri-operative course, short- and long-term outcomes. We report results using descriptive statistics.

Results

We identified 124 IVDU patients with surgically managed endocarditis. Mean age was 37 years (SD 11), 61% were females and 8% had redo surgery. During admission, 45% (n=56) of the patients had an embolic event: 63% pulmonary, 30% cerebral, 18% peripheral and 11% mesenteric. Causative organisms included Methicillin-Sensitive Staphylococcus Aureus (51%, n=63), Methicillin-Resistant Staphylococcus Aureus (15%, n=19), Streptococcus Viridans (2%, n=2), and others (31%, n=38). Emergency cardiac surgery was performed for 42% of patients (n=52). Most patients (84%) had single valve intervention: 53% tricuspid, 18% aortic and 13% mitral. Double valve interventions occurred in 15% (n=18). Overall, bioprosthetic replacement was most commonly chosen (79%, n=98). In-hospital mortality was 7% (n=8). Median length of stay in hospital was 13 days (IQR 8,21) and ICU 2 days (IQR 1,6). Mortality at longest available follow-up was 24% (n=30), with a median follow-up of 129 days (IQR 15,416). Valve reintervention rate was 11% (n=13) and readmission rate was 14% (n=17) at a median of 275 days (IQR 54,502).

Conclusion

Despite their critical condition, IVDU patients with endocarditis have good intra-hospital outcomes. Challenges occur after hospital discharge with loss of follow-up and high short-term mortality. IVDU relapse likely accounts for some of these issues. In-hospital and community comprehensive addiction management may improve these patients' outcomes beyond the surgical procedure.

Annual rate 2009–2018

Funding Acknowledgement

Type of funding source: None

Performance status agreement assessed by the patient and clinician in a rapid access lung cancer service: Can either predict completion of treatment?

INTRODUCTION

Clinician-rated performance status (C-PS) is used routinely to predict whether patients are fit enough to undergo treatment for lung cancer. However, a good proportion of those with seemingly good C-PS do not go on to receive, let alone complete treatment. The value of C-PS in accurately predicting this is unclear, as is the merit of evaluating patient-rated PS (P-PS).

OBJECTIVES

Our aim was to prospectively assess Eastern Cooperative Oncology Group (ECOG) and Karnofsky C-PS and P-PS in patients attending a rapid access lung cancer service (RALCS), the agreement between these scores, and whether any score could predict receipt and completion of multidisciplinary team (MDT)-planned treatment.

RESULTS

ECOG and Karnofsky scores were highly correlated (Spearman's rho -0.79 for C-PS and -0.828 for P-PS, both p < 0.001). There was poor agreement between C-PS and P-PS scores (kappa statistics 0.275 for ECOG and 0.172 for Karnofsky); however, clinicians did not tend to consistently under- or overestimate patients' scores. ECOG P-PS showed an association with completion of MDT-planned treatment (p = 0.007), but C-PS did not.

CONCLUSION

Clinician-rated PS was not associated with completion of MDT-planned treatment, but there may be a role for patient-rated PS. C-PS and P-PS were poorly correlated in a RALCS.

The need for integrated public health surveillance to address sexually transmitted and blood-borne syndemics

A national approach to addressing sexually transmitted and blood-borne infections (STBBIs) was recently articulated in the Public Health Agency of Canada's new A Pan-Canadian Framework for Action: Reducing the health impact of sexually transmitted and blood-borne infections in Canada by 2030. This Framework promotes an integrated approach, with a focus on the key populations that are affected by overlapping epidemics (i.e., syndemics). We advance the idea that integrating surveillance would be helpful in characterizing and understanding the populations, locations, risk behaviours and other drivers that contribute to STBBI syndemics. The creation of matched or linked data systems that would allow routine reporting of integrated data is challenged by the technical barriers of integrating data silos as well as by the privacy and ethical considerations of merging sensitive individual-level data. Lessons can be learned from jurisdictions where an improved understanding of syndemics, through integrated STBBI surveillance, has led to more efficient and effective operational, program and policy decisions. Emerging enablers include the development of data standards and guidelines, investment in resources to overcome technical challenges and community engagement to support the ethical and non-stigmatizing use of integrated data. The Framework's call to action offers an opportunity for national discussion on priorities and resources needed to advance STBBI syndemic surveillance for local, regional and national reporting in Canada.

Longitudinal study to assess impact of smoking at diagnosis and quitting on 1-year survival for people with non-small cell lung cancer

OBJECTIVES

To update the prevalence of smoking in people as they were diagnosed with non-small cell lung cancer (NSCLC) and to see whether smoking status at baseline and quitting are independently associated with 1-year survival.

DESIGN

A real-world cohort study following patients from diagnosis for up to 1 year or until death.

SETTING

UK multi-centre study (28 sites) based in secondary and primary care.

PARTICIPANTS

1124 patients with newly diagnosed NSCLC between 2010-2016.

MAIN OUTCOME MEASURES

Smoking status was validated at diagnosis and at every routine and emergency hospital visit. Cancer treatments were offered according to local multi-disciplinary team decisions following UK guidelines and smoking cessation treatments offered according to local practice /availability. Survival analysis and Cox Proportional Hazards Modelling examined the associations of a) smoking at baseline and b) quitting smoking, on survival at 1 year.

RESULTS

77% of never smokers, 60% of ex-smokers and 57% of current smokers, were alive at 1 year (p = 0.01). After adjusting for age, stage, EGOG, surgery and gender, ex smokers (adjusted HR 1.96, 95% CI 1.16-2.31) and current smokers (aHR 2.04, 1.19-3.48) were both more likely to die within one year. 23% of smokers with NSCLC quit within 3 months of diagnosis. At 1 year, 69% of those who quit were alive versus 53% of those who continued to smoke (p < 0.01). After adjusting the risk of dying was lower (aHR 0.75), in those who quit smoking, although this was not statistically significant (p = 0.23).

CONCLUSIONS

This is the largest prospective study that validates smoking in NSCLC; it shows a third of people are smoking at the time of diagnosis. Smokers have lower 12-month survival than never and ex -smokers. Quitting smoking was associated with 25% reduction in mortality which may be clinically important although not statistically significant, after adjusting for other factors.

Impact of hydration and nutrition on personal performance in the clinical workplace

As clinicians we sometimes fail to look after ourselves at work. We often do not drink enough during the day or miss lunch breaks while caring for patients, and this can be particularly evident during an all-day operating list when procedures are long and complex. Some operating theatre staff do not even eat breakfast regularly. Inadequate intake of fluids or nutrition can impair performance, lead to tiredness and headaches, and may compromise both our own health and the care we provide to patients. Other high-risk organisations, including aviation, have recognised that employees must look after themselves if they are to optimise their performance. In this review, we discuss the importance of adequate hydration and nutrition at work to raise awareness that this is essential if we are to provide the best care for our patients.

Association of sarcopenia and observed physical performance with attainment of multidisciplinary team planned treatment in non-small cell lung cancer: an observational study protocol

BACKGROUND

Non-small cell lung cancer (NSCLC) frequently presents in advanced stages. A significant proportion of those with reportedly good ECOG performance status (PS) fail to receive planned multidisciplinary team (MDT) treatment, often for functional reasons, but an objective decline in physical performance is not well described. Sarcopenia, or loss of muscle mass, is an integral part of cancer cachexia. However, changes in both muscle mass and physical performance may predate clinically overt cachexia, and may be present even with normal body mass index. Physical fitness for treatment is currently subjectively assessed by means of the PS score, which may be inadequate in predicting tolerance to treatment. This study aims to evaluate whether measuring physical performance and muscle mass at baseline in NSCLC patients, in addition to PS score, is able to predict commencement and successful completion of MDT-planned treatment.

METHODS/DESIGN

This is a prospective, single-centre exploratory study of NSCLC patients attending a Rapid Access Lung Cancer clinic. Baseline data collected are (methods in brackets): physical performance (Short Physical Performance Battery), muscle mass (bioelectrical impedance ± dual energy x-ray absorptiometry), patient and physician-assessed PS (ECOG and Karnofsky), nutritional status and presence of cachexia. Longitudinal data consists of receipt and completion of MDT treatment plan. The primary outcome measure is commencement of MDT-planned treatment, and important secondary outcomes include successful completion of treatment, length of stay in surgical patients, and risk of chemotherapy- and radiotherapy-related side effects.

DISCUSSION

A more comprehensive assessment of phenotype, particularly with regards to physical performance and muscle mass, will provide additional discriminatory information of patients' fitness for treatment. If positive, this study has the potential to identify targets for early intervention in those who are at risk of deterioration. This will subsequently enable optimisation of performance of patients with NSCLC, in anticipation of systemic treatment.

Division of the spinal accessory nerve in the anterior triangle: a prospective clinical study

The anatomical relation between the spinal accessory nerve and internal jugular vein is well documented, but other variants of the nerve, including the contributions of the cervical plexus to supply motor fibres to the trapezius, are less well known. We have previously described an anatomical variant in which the spinal accessory nerve divided before entering the sternocleidomastoid, and the inferior trunk passed directly under it to supply the trapezius. We now present a prospective study of 133 neck dissections (excluding radical dissections) in which a meticulous search was made for the variant in the anterior triangle of the neck during operation. We found it in 3 necks (2%). One of the 3 patients had a bilateral neck dissection but it was found on one side only, and in 2 cases it communicated with the cervical plexus. In all 3, stimulation of the inferior division resulted in contraction of the trapezius while the upper division was found to supply the sternocleidomastoid only. The finding of this variant, which was more common than first thought, highlights the need for meticulous dissection of the nerve before it enters the sternocleidomastoid to ensure that, when present, the inferior branch is preserved to minimise potential postoperative shoulder dysfunction. Further research including a cadaveric study is needed to understand this important variant more fully.

SEB-3, a CRF receptor-like GPCR, regulates locomotor activity states, stress responses and ethanol tolerance in Caenorhabditis elegans

The CRF (corticotropin-releasing factor) system is a key mediator of the stress response. Alterations in CRF signaling have been implicated in drug craving and ethanol consumption. The development of negative reinforcement via activation of brain stress systems has been proposed as a mechanism that contributes to alcohol dependence. Here, we isolated a gain-of-function allele of seb-3, a CRF receptor-like GPCR in Caenorhabditis elegans, providing an in vivo model of a constitutively activated stress system. We also characterized a loss-of-function allele of seb-3 and showed that SEB-3 positively regulates a stress response that leads to an enhanced active state of locomotion, behavioral arousal and tremor. SEB-3 also contributed to acute tolerance to ethanol and to the development of tremor during ethanol withdrawal. Furthermore, we found that a specific CRF(1) receptor antagonist reduced acute functional tolerance to ethanol in mice. These findings demonstrate functional conservation of the CRF system in responses to stress and ethanol in vertebrates and invertebrates.

A study of radionuclides, metals and stable lead isotope ratios in sediments and soils in the vicinity of natural U-mineralisation areas in the Northern Territory

Australian guidelines recommend that tailings materials from uranium (U) mining and milling be contained without any detrimental impact on the environment for at least 1000 years. Natural analogue sites are being investigated to determine if they can provide data on the rates of natural erosion processes which occur over these timescales, for input into predictive geomorphic computer models. This paper presents radionuclide, metal and stable lead (Pb) isotope data from sediment cores and surface soils in the vicinity of two mineralised areas in the Alligator Rivers Region. Surface scrapes from the natural Anomaly #2, south of the Ranger mineral lease, exhibit radiogenic (206)Pb/(207)Pb and (208)Pb/(207)Pb ratios, and elevated U and metal concentrations typical for a near surface U anomaly. In contrast, samples taken from the Koongarra mineral lease (KML) show radionuclide activity and metal concentrations similar to natural areas elsewhere in the Alligator Rivers Region and Pb isotope ratios are closer to present day average crustal ratios (PDAC), as the orebodies at KML are covered by surficial sand. A sediment core collected from Anbangbang Billabong, downstream of KML, exhibits small variations in Pb isotope ratios that indicate that approximately 1% of the upper sediments in the sediment core may be derived from material originating from the U anomaly at Koongarra.

Non-target effects of transgenic blight-resistant American chestnut (Fagales: Fagaceae) on insect herbivores

American chestnut [Castanea dentata (Marshall) Borkhausen], a canopy dominant species across wide swaths of eastern North America, was reduced to an understory shrub after introduction of the blight fungus [Cryphonectria parasitica (Murrill) Barr] in the early 1900s. Restoration of American chestnut by using biotechnology is promising, but the imprecise nature of transgenesis may inadvertently alter tree phenotype, thus potentially impacting ecologically dependent organisms. We quantified effects of genetic engineering and fungal inoculation of trees on insect herbivores by using transgenic American chestnuts expressing an oxalate oxidase gene and wild-type American and Chinese (C. mollissima Blume) chestnuts. Of three generalist folivores bioassayed, only gypsy moth [Lymantria dispar (L.)] was affected by genetic modification, exhibiting faster growth on transgenic than on wild-type chestnuts, whereas growth of polyphemus moth [Antheraea polyphemus (Cramer)] differed between wild-type species, and fall webworm [Hyphantria cunea (Drury)] performed equally on all trees. Inoculation of chestnuts with blight fungus had no effect on the growth of two herbivores assayed (polyphemus moth and fall webworm). Enhanced fitness of gypsy moth on genetically modified trees may hinder restoration efforts if this invasive herbivore's growth is improved because of transgene expression.

A uniaxial tensile stage with tracking capabilities for micro X-ray diffraction applications

First results are presented for a uniaxial tensile stage designed to operate on a scanning micro X-ray diffraction synchrotron beamline. The new tensile stage allows experiments at typical loading cycles used in standard engineering stress–strain tests. Several key features have been implemented to supportin situloading experiments at the intragranular length scale. The physical size and weight of the load cell were minimized to maintain the correct working distance for the X-ray focusing optics and to avoid overloading the high-resolution raster scan translation stages. A high-magnification optical microscope and image correlation code were implemented to enable automated online tracking capabilities during macroscopic elongation of the sample. Preliminaryin situtensile loading experiments conducted on beamline 12.3.2 at the Advanced Light Source using a polycrystalline commercial-purity Ti test piece showed that the elastic–plastic response of individual grains could be measured with submicrometre spatial resolution. The experiments highlight the unique instrumentation capabilities of the tensile stage for direct measurement of deviatoric strain and observation of dislocation patterning on an intragranular length scale as a function of applied load.

Economic burden and healthcare utilization associated with castration-resistant prostate cancer in a commercial and Medicare Advantage US patient population

OBJECTIVE

Prostate cancer is a leading cause of cancer death in men in the US. Castration-resistant prostate cancer (CRPC) is an advanced form of the disease and has a poor prognosis and limited treatment options. The objective of this study was to identify patients with CRPC from a medical claims database, and determine the prostate cancer-related economic burden and healthcare utilization of these patients.

METHODS

This was a retrospective study using claims and enrollment information from a large US database linkable to laboratory data. Male patients aged 40 or older who were diagnosed with prostate cancer and received surgical or medical castration between July 1, 2001 and December 1, 2007 were considered for study inclusion. Patients with CRPC were initially identified based on at least two increases in prostrate-specific antigen (PSA) values. Due to the small number of patients with available PSA results data, logistic regression modeling using characteristics of patients with known CRPC was used to identify a larger set of patients with likely CRPC. Per-patient per-month healthcare utilization and costs were determined using medical and pharmacy claims data.

RESULTS

The final sample of patients with likely CRPC as determined by regression modeling included 349 patients with known CRPC identified from the database on the basis of PSA results and an additional 2391 with likely CRPC. Within this final sample of 2740 CRPC patients, there was a per-patient per-month average of 1.43 prostate cancer-related ambulatory visits, 0.04 prostate cancer-related inpatient stays, and 0.01 prostate cancer-related ER visits. Average per-patient per-month prostate cancer-related costs were $1152 (SD = $2073) for ambulatory visits, $559 (SD = $2383) for inpatient stays, $72 (SD = $229) for pharmacy costs, and $1 (SD = $14) for ER visits. Total per-patient per-month prostate cancer-related costs were on average $1799 (SD = $3505), and these costs comprised about half of the all-cause healthcare costs for these patients.

CONCLUSIONS

CRPC is a costly disease, with ambulatory visits and inpatient care accounting for a substantial proportion of the economic burden. Limitations related to the use of retrospective claims data should be considered when interpreting these results.

Perceived exertion influences pacing among ultramarathon runners but post-race mood change is associated with performance expectancy

Objectives. This study investigated whether post-race mood changes among ultramarathon runners are associated with perceived exertion or the discrepancy between their actual and predicted performance times.Methods. Eight runners completed the Puffer ultramarathon, which is a challenging 73 km mountainous race across Table Mountain National Park in South Africa. Each runner completed a series of profile of mood state questionnaires (POMS) 2 days before the race (baseline), on the morning of the race (pre-race) and immediately after the race (post-race). Ratings of perceived exertion (RPE) were measured at 13 points during the race using the Borg 6-20 scale. The accuracy of performance expectationswas measured as the difference between runners’ actual and predicted race times.Results. Average completion time was 11:31:36±00:26:32 (h :mm:ss), average running speed was 6.4±2.2 km.hr-1 and averageRPE was 14.1±2.0. Increased POMS confusion was found before the race (33.30.7 v. 37.1±5.2, p=0.014; baseline v. pre-race). Post-race increases in POMS total mood disturbance (TMD) were found (168.3±20 v. 137.5±6.3, p=0.001; post race v. baseline) characterised by decreased vigour (43.3±4.0 v. 33.5±7.0, p=0.008; baseline v. post race), increased confusion (33.3±0.7 v. 38.5±4.8, p=0.006; baseline v. post race) and increased fatigue (37.8±4.8 v. 53.8±7.3, p=0.0003; baseline v. post race). A linear increase in RPE was found during the race (r=0.737, p=0.002).The magnitude of their post-race mood change (r=-0.704, p=0.026) was not found to be associated with runners’ average RPE but was found to be negatively correlated with accuracy of the performance predictions. A time series analysis indicated that POMS TMD would have taken 142±89 min to recover. Conclusions. The results show that RPE influences the wayultramarathon runners pace themselves more than performance expectancy but performance expectations have a greater influence on post-race mood. The magnitude of post-race mood change is associated with the extent of discrepancy between runners’ predicted and actual performance. This has implications for designing appropriate goals and pacing strategies for ultraendurance athletes. 

Radioactive and radiogenic isotopes in sediments from Cooper Creek, Western Arnhem Land

Protection of the environment post-mining is a key objective of rehabilitation, especially where runoff and erosion from rehabilitated mine sites could potentially lead to contamination of the surrounding land and watercourses. As part of an overall assessment of the success of rehabilitation at the former Nabarlek uranium (U) mine, an appraisal of stable lead (Pb) isotopes, radionuclides and trace metals within sediments and soils was conducted to determine the off site impacts from a spatial and temporal perspective. The study found localised areas on and adjacent to the site where soils had elevated levels of trace metals and radionuclides. Lead isotope ratios are highly radiogenic in some samples, indicating the presence of U-rich material. There is some indication that erosion products with more radiogenic Pb isotope ratios have deposited in sediments downstream of the former ore body. However, there is no indication that the radiogenic erosion products found on the mine site at present have significantly contaminated sediments further downstream of Cooper Creek.

A laboratory based system for laue micro x-ray diffraction

A laboratory diffraction system capable of illuminating individual grains in a polycrystalline matrix is described. Using a microfocus x-ray source equipped with a tungsten anode and prefigured monocapillary optic, a micro-x-ray diffraction system with a 10 microm beam was developed. The beam profile generated by the ellipsoidal capillary was determined using the "knife edge" approach. Measurement of the capillary performance, indicated a beam divergence of 14 mrad and a useable energy bandpass from 5.5 to 19 keV. Utilizing the polychromatic nature of the incident x-ray beam and application of the Laue indexing software package X-Ray Micro-Diffraction Analysis Software, the orientation and deviatoric strain of single grains in a polycrystalline material can be studied. To highlight the system potential the grain orientation and strain distribution of individual grains in a polycrystalline magnesium alloy (Mg 0.2 wt % Nd) was mapped before and after tensile loading. A basal (0002) orientation was identified in the as-rolled annealed alloy; after tensile loading some grains were observed to undergo an orientation change of 30 degrees with respect to (0002). The applied uniaxial load was measured as an increase in the deviatoric tensile strain parallel to the load axis.

Resilience of mycorrhizal fungi on defoliated and fertilized hybrid poplars

We examined the effects of fertilization and gypsy moth defoliation of hybrid poplar (Populus ×canadensis Moench 'Eugenei') on ectomycorrhizal (ECM) and arbuscular mycorrhizal (AM) fungal colonization, ECM richness, and ECM composition in the summers of 1997 and 1998. The factorial experiment included two levels of defoliation (defoliated and control) and fertilization (100 kg N·ha–1and control). Gypsy moth (Lymantria dispar L.) populations were manipulated to obtain defoliation in the summer of 1996, 1997, and 1998; fertilization subplots were fertilized with NH4NO3(100 kg N·ha–1) in the spring of these years. There were no significant effects of defoliation on ECM or AM colonization in either year; there was a significant (p ≤ 0.05) decline in AM colonization in fertilized plots in 1997 and a significant interaction between defoliation and fertilization effects on ECM colonization in 1997. In the nondefoliated plots, ECM fungal colonization increased, whereas AM colonization decreased because of fertilization. In the defoliated plots, neither ECM nor AM colonization was affected by fertilization. ECM community composition and richness were unchanged by any treatment. The small and transient effects of defoliation and fertilization on poplar AMs and ECMs demonstrate the tolerance of these early-successional trees to defoliation and their ability to rapidly use high levels of available nitrogen.Key words: Populus, nitrogen, ectomycorrhizas, arbuscular mycorrhizas, ectomycorrhizas, Lymantria dispar (gypsy moth), defoliation.

A comparison of the effect of elemental and immune-enhancing polymeric jejunal feeding on exocrine pancreatic function

BACKGROUND

There are few studies examining the effect of jejunal feeding on pancreatic exocrine output. The purpose of this study was to compare the effects of jejunal feeding with an elemental formula (EF) and with a polymeric immune-enhancing formula (PIEF) on pancreatic exocrine function.

METHODS

Patients undergoing a partial pancreatectomy had a jejunal feeding tube inserted and a pancreatic stent exteriorized, facilitating collection of pancreatic secretions. Postoperatively, patients underwent a secretin-stimulation test to document adequate pancreatic reserve. Patients were then randomized to receive jejunal feeding with EF or with PIEF for a 24-hour period, followed by a washout period of feeding with dextrose, and subsequent jejunal feeding with EF or PIEF.

RESULTS

The secretin-stimulation test demonstrated significant pancreatic reserve in all patients. There was a mild increase in pancreatic exocrine secretion with jejunal feeding with EF and PIEF compared with baseline and with dextrose. There was increased bicarbonate secretion with EF compared with PIEF, but there were no other significant differences in pancreatic exocrine function.

CONCLUSIONS

In this model of partial pancreatectomy, there was no significant difference in pancreatic exocrine output when use of an EF was compared with use of a PIEF for jejunal feeding. Further clinical studies are needed to determine the potential role of PIEF in pancreatic disease.