Search

Cardiopulmonary exercise testing (CPET) allows the clinician to objectively evaluate symptoms and important functions. CPET also arms the investigator with a powerful tool to better understand the respiratory system role as an engaged participant of a fully integrated physiologic system in humans. The insights gained mean that CPET can aid in the assessment of activity limitation and dyspnea, in evaluating disability and disease severity, in judging risk and prognosis, and in considering the suitability for specific interventions such as transplantation. In the research laboratory, CPET can contribute to the complete evaluation of new therapeutic or management agents, provide physiologic understanding for various hypotheses and new-found research results, and aid in discovery to further our understanding of the complex behaviour and interaction of the human respiratory system. While these benefits are well known to those working closely in the field, the need for greater and more effective dissemination of these benefits is required. Hence, this special issue focuses on cardiopulmonary exercise testing. We begin with M. K. Stickland et al. reviewing normal exercise physiology, as well as providing guidelines for the understanding of cardiopulmonary exercise test results. Techniques to ensure valid measurements of inspiratory capacity permitting a learned assessment of ventilatory constraint are outlined by J. A. Guenette and colleagues, while R. Ramos and others review the clinical usefulness of rapid incremental testing protocols. J. C. da Silva et al. examine the best criteria to determine ramp exercise testing speed in their original research study. Meanwhile, I. Vogiatzis and colleagues undertake a detailed review of varied mechanisms contributing to activity limitation in chronic lung diseases. B. Borel et al. explore the responsiveness of different exercise testing protocols to therapeutic interventions in COPD. A. Apostolo et al. review the interaction and consequences for the lungs in the setting of chronic heart failure, while C. H. Kim and colleagues report original research assessing the validity of a new multivariate index for grading gas exchange severity in patients with pulmonary arterial hypertension and with heart failure. Finally, D. E. O'Donnell et al. review the respiratory consequences of obesity and its impact on exercise performance in both health and in COPD. We hope you find these articles both interesting and useful. We are confident that they will become meaningful resources in this field.

We have previously shown that respiratory factors (arterial hypoxemia and/or pulmonary mechanics) contribute to limit maximal incremental exercise in interstitial lung disease (ILD). In this study, we tested the hypothesis that arterial hypoxemia, not pulmonary mechanics, primarily limits maximal exercise in subjects with ILD. Seven subjects with ILD underwent two incremental exercise tests in random order. Test 1: breathing room air (RA); Test 2: breathing 60% O2 with added external dead space (O2VD). Added VD was used to prevent the fall in minute ventilation (VI) while breathing O2. All subjects demonstrated impaired exercise performance (maximal oxygen uptake [VO2], 56 +/- 13% predicted) while breathing RA. There was a significant increase in peak VI (RA, 64.9 +/- 22.3 L/min versus O2VD, 71.0 +/- 20.6; p < 0.05), maximal work rate (RA, 99 +/- 12 watts versus O2VD, 109 +/- 15 watts; p < 0.01), exercise duration (RA, 383 +/- 67 s versus O2VD; 426 +/- 72 s; p < 0.0005) and maximal VO2 (RA, 1.25 +/- 0.21 L/min versus O2VD, 1.39 +/- 0.26; p < 0.05) during the O2VD exercise test. There was a significant correlation between the percent increase in exercise duration during the O2VD test and the DLCO (r = -0.813, p < 0.05). At matched levels of ventilation, subjects demonstrated a significantly deeper and slower pattern of breathing during the O2VD test. Because subjects with ILD were able to further improve their exercise and further increase their VI during the O2VD exercise study, we conclude that arterial hypoxemia, and not respiratory mechanics, predominantly limits maximal incremental exercise in subjects with ILD.

Exercise testing has become an essential tool in the management of patients with CAL. In addition to its ability to assess exercise limitation objectively, it has usefulness in detecting the presence or absence of associated disease processes, in assessing the response to therapies, in allowing assessment of the importance of psychological factors in exercise limitation, and in guiding prescription for exercise rehabilitation programs. Although much is known about the clinical usefulness of exercise testing in this disease, and much has been learned about how this disease functionally impairs the exercise capacity of the patient, additional study is necessary to appreciate fully the physiologic abnormalities demonstrated by patients with CAL during exercise.

Cloransulam-methyl, N-(2-carbomethoxy-6-chlorophenyl)-5-ethoxy-7-fluoro[1,2,4]triazolo[1,5-c]pyrimidine-2-sulfonamide, is a new broad-spectrum herbicide for use in soybeans. The U.S. Environmental Protection Agency requires that analytical methodology be developed to enforce tolerance levels of pesticides in food crops. This paper describes the method developed to enforce tolerance levels of cloransulam-methyl in soybeans and soybean forage, hay, and processed commodities. The method description includes validation data supporting a lower limit of quantitation of 0.01 μg/g (10 ppb) for cloransulam-methyl in each matrix. Extracts of each matrix are purified using C18 and neutral alumina solid phase extraction. Cloransulam-methyl is derivatized, using (trimethylsilyl)diazomethane, to the N-methylcloransulam-methyl. Quantitation and simultaneous confirmation of residues of cloransulam-methyl as N-methylcloransulam-methyl employ gas chromatography with mass spectrometric detection using electron impact ioniza...

We demonstrated a technique to control the placement of 6 nm-diameter CdSe and 5 nm-diameter CdSe/CdZnS colloidal quantum dots (QDs) through electron-beam lithography. This QD-placement technique resulted in an average of three QDs in each cluster, and 87% of the templated sites were occupied by at least one QD. These QD clusters could be in close proximity to one another, with a minimum separation of 12 nm. Photoluminescence measurements of the fabricated QD clusters showed intermittent photoluminescence, which indicates that the QDs were optically active after the fabrication process. This optimized top-down lithographic process is a step towards the integration of individual QDs in optoelectronic and nano-optical systems., Hertz Foundation (Fellowship), United States. Dept. of Energy. Office of Basic Energy Sciences (Award DE-SC0001088)

Recent reports have suggested that low-dose nebulized morphine may improve exercise tolerance in patients with interstitial lung disease (ILD) by acting on peripheral opioid-sensitive pulmonary receptors. We therefore examined whether the administration of low-dose nebulized morphine would influence dyspnea or the breathing pattern during exercise of subjects with ILD and improve their exercise performance. Each of six subjects with ILD underwent three maximal incremental cycle ergometer tests, each test separated from the last by at least 3 d. Each exercise test was similar except that 30 min before exercise, the subjects received nebulized saline (control), morphine 2.5 mg, or morphine 5.0 mg, respectively, in double-blinded fashion. No significant differences were noted in exercise duration, maximal workload, or sense of dyspnea at the end of exercise in the control test and the tests with either morphine 2.5 mg or morphine 5.0 mg. Nor were significant differences noted in resting, submaximal, or end-exercise measurements of oxygen uptake (VO2), carbon dioxide output (VCO2), end-tidal CO2 (PETCO2), oxygen saturation (SaO2), minute ventilation (VI), respiratory frequency (f), tidal volume (VT), or heart rate (HR) in the three tests. Low-dose nebulized morphine did not alter the subjects' breathing pattern or affect the relationship between dyspnea and ventilation during exercise. No significant side effects were noted. The administration of low-dose nebulized morphine to subjects with ILD neither relieves their dyspnea during exercise nor improves their maximal exercise performance.

A method is described for the determination of tebuthiuron and five metabolites [metabolite 104, N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N-methylurea ; metabolite 106, N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl] urea ; metabolite 109, N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N'-(hydroxymethyl)-N-methylurea; metabolite 104(OH), N-[5-(2-hydroxy-1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N-methylurea; and metabolite 109(OH), N-[5-(2-hydroxy-1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N'-(hydroxymethyl)-N-methylurea] in bovine milk. The compounds are extracted from acid-hydrolyzed milk with ethyl acetate or methyl tert-butyl ether, and samples are purified with alumina and C 18 solid phase extractions. Following trifluoroacetylation and silylation, the analytes are quantitated by gas chromatography with mass spectrometric detection in the selected ion monitoring mode. During hydrolysis, metabolites 109 and 109(OH) are converted to 104 and 104(OH), respectively ; therefore, quantitation of metabolites 104 and 104(OH) includes these two metabolites as well. Additional purification and derivatization steps are required for the isolation and determination of metabolite 106, thus necessitating separate analysis. Limits of quantitation for all of the analytes range from 0.02 to 0.09 μg/mL.

Scotty J Butcher,1 Brendan J Pikaluk,2 Robyn L Chura,1 Mark J Walkner,1 Jonathan P Farthing,2 Darcy D Marciniuk31School of Physical Therapy, University of Saskatchewan, Saskatoon, SK, Canada; 2College of Kinesiology, University of Saskatchewan, Saskatoon, SK, Canada; 3Division of Respiratory, Critical Care and Sleep Medicine, University of Saskatchewan, Saskatoon, SK, CanadaAbstract: High-level activities are typically not performed by patients with chronic obstructive pulmonary disease (COPD), which results in reduced functional performance; however, the physiological parameters that contribute to this reduced performance are unknown. The aim of this study was to determine the relationships between high-level functional performance, leg muscle strength/power, aerobic power, and anaerobic power. Thirteen patients with COPD underwent an incremental maximal cardiopulmonary exercise test, quadriceps isokinetic dynamometry (isometric peak torque and rate of torque development; concentric isokinetic peak torque at 90°/sec, 180°/sec, and 270°/sec; and eccentric peak torque at 90°/sec), a steep ramp anaerobic test (SRAT) (increments of 25 watts every 10 seconds), and three functional measures (timed up and go [TUG], timed stair climb power [SCPT], and 30-second sit-to-stand test [STS]). TUG time correlated strongly (P < 0.05) with all muscle strength variables and with the SRAT. Isometric peak torque was the strongest determinant of TUG time (r = –0.92). SCPT and STS each correlated with all muscle strength variables except concentric at 270°/sec and with the SRAT. The SRAT was the strongest determinant of SCPT (r = 0.91), and eccentric peak torque at 90°/sec was most significantly associated with STS (r = 0.81). Performance on the SRAT (anaerobic power); slower-velocity concentric, eccentric, and isometric contractions; and rate of torque development are reflected in all functional tests, whereas cardiopulmonary exercise test performance (aerobic power) was not associated with any of the functional or muscle tests. High-level functional performance in patients with COPD is associated with physiological parameters that require high levels of muscle force and anaerobic work rates.Keywords: stair climb, sit to stand, timed up and go, steep ramp, isokinetic

We present the first semiconductor nanocrystal films of nanoscale dimensions that are electrically conductive and crack-free. These films make it possible to study the electrical properties intrinsic to the nanocrystals unimpeded by defects such as cracking and clustering that typically exist in larger-scale films. We find that the electrical conductivity of the nanoscale films is 180 times higher than that of drop-cast, microscopic films made of the same type of nanocrystal. Our technique for forming the nanoscale films is based on electron-beam lithography and a lift-off process. The patterns have dimensions as small as 30 nm and are positioned on a surface with 30 nm precision. The method is flexible in the choice of nanocrystal core-shell materials and ligands. We demonstrate patterns with PbS, PbSe, and CdSe cores and Zn(0.5)Cd(0.5)Se-Zn(0.5)Cd(0.5)S core-shell nanocrystals with a variety of ligands. We achieve unprecedented versatility in integrating semiconductor nanocrystal films into device structures both for studying the intrinsic electrical properties of the nanocrystals and for nanoscale optoelectronic applications.

The Steep Ramp Anaerobic Test (SRAT) was developed as a clinical test of anaerobic leg muscle function for use in determining anaerobic power and in prescribing high-intensity interval exercise in patients with chronic heart failure and Chronic Obstructive Pulmonary Disease (COPD); however, neither the test-retest reliability nor the physiological qualities of this test have been reported. We therefore, assessed test-retest reliability of the SRAT and the physiological characteristics associated with the test in patients with COPD. 11 COPD patients (mean FEV143% predicted) performed a cardiopulmonary exercise test (CPET) on Day 1, and an SRAT and a 30-second Wingate anaerobic test (WAT) on each of Days 2 and 3. The SRAT showed a high degree of test-retest reliability (ICC=0.99;CV=3.8%, and bias 4.5 W, error −15.3–24.4 W). Power output on the SRAT was 157 W compared to 66 W on the CPET and 231 W on the WAT. Despite the differences in workload, patients exhibited similar metabolic and ventilatory responses between the three tests. Measures of ventilatory constraint correlated more strongly with the CPET than the WAT; however, physiological variables correlated more strongly with the WAT. The SRAT is a highly reliable test that better reflects physiological performance on a WAT power test despite a similar level of ventilatory constraint compared to CPET.

We investigate the bias-stress effect in field-effect transistors (FETs) consisting of 1,2-ethanedithiol-treated PbS quantum dot (QD) films as charge transport layers in a top-gated configuration. The FETs exhibit ambipolar operation with typical mobilities on the order of μ(e) = 8 × 10(-3) cm(2) V(-1) s(-1) in n-channel operation and μ(h) = 1 × 10(-3) cm(2) V(-1) s(-1) in p-channel operation. When the FET is turned on in n-channel or p-channel mode, the established drain-source current rapidly decreases from its initial magnitude in a stretched exponential decay, manifesting the bias-stress effect. The choice of dielectric is found to have little effect on the characteristics of this bias-stress effect, leading us to conclude that the associated charge-trapping process originates within the QD film itself. Measurements of bias-stress-induced time-dependent decays in the drain-source current (I(DS)) are well fit to stretched exponential functions, and the time constants of these decays in n-channel and p-channel operation are found to follow thermally activated (Arrhenius) behavior. Measurements as a function of QD size reveal that the stressing process in n-channel operation is faster for QDs of a smaller diameter while stress in p-channel operation is found to be relatively invariant to QD size. Our results are consistent with a mechanism in which field-induced nanoscale morphological changes within the QD film result in screening of the applied gate field. This phenomenon is entirely recoverable, which allows us to repeatedly observe bias stress and recovery characteristics on the same device. This work elucidates aspects of charge transport in chemically treated lead chalcogenide QD films and is of relevance to ongoing investigations toward employing these films in optoelectronic devices.

The spondyloarthropathies (SpA) are a group of inflammatory rheumatic diseases affecting the spine, peripheral joints and nonarticular structures. Often referred to as “seronegative” due to the absence of rheumatoid factor, SpA include ankylosing spondylitis (AS), reactive arthritis (ReA), enteropathic (IBD) associated arthritis, psoriatic arthritis (PsA), as well as undifferentiated, and juvenile SpA. A broad and overlapping spectrum of disease presentations creates difficulties in determining an initial diagnosis. In the last 10 years treatment options have expanded.

We fabricated planar PbS quantum dot devices with ohmic and Schottky type electrodes and characterized them using scanning photocurrent and photovoltage microscopies. The microscopy techniques used in this investigation allow for interrogation of the lateral depletion width and related photovoltaic properties in the planar Schottky type contacts. Titanium/QD contacts exhibited depletion widths that varied over a wide range as a function of bias voltage, while the gold/QD contacts showed ohmic behavior over the same voltage range.

Introduction The prescription of physical activity for hospitalized patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) can be complicated by the presence of comorbidities. The current research aimed to synthesize the relevant literature on the benefits of exercise for people with multimorbidities who experience an AECOPD, and ask: What are the parameters and outcomes of exercise in AECOPD and in conditions that are common comorbidities as reported by systematic reviews (SRs)? Methods An SR was performed using the Cochrane Collaboration protocol. Nine electronic databases were searched up to July 2011. Articles were included if they (1) described participants with AECOPD, chronic obstructive pulmonary disease (COPD), or one of eleven common comorbidities, (2) were an SR, (3) examined aerobic training (AT), resistance training (RT), balance training (BT), or a combination thereof, (4) included at least one outcome of fitness, and (5) compared exercise training versus control/sham. Results This synthesis examined 58 SRs of exercise training in people with AECOPD, COPD, or eleven chronic conditions commonly associated with COPD. Meta-analyses of endurance (aerobic or exercise capacity, 6-minute walk distance – 6MWD) were shown to significantly improve in most conditions (except osteoarthritis, osteoporosis, and depression), whereas strength was shown to improve in five of the 13 conditions searched: COPD, older adults, heart failure, ischemic heart disease, and diabetes. Several studies of different conditions also reported improvements in quality of life, function, and control or prevention outcomes. Meta-analyses also demonstrate that exercise training decreases the risk of mortality in older adults, and those with COPD or ischemic heart disease. The most common types of training were AT and RT. BT and functional training were commonly applied in older adults. The quality of the SRs for most conditions was moderate to excellent (>65%) as evaluated by AMSTAR scores. Conclusion In summary, this synthesis showed evidence of significant benefits from exercise training in AECOPD, COPD, and conditions that are common comorbidities. A broader approach to exercise and activity prescription in pulmonary rehabilitation may induce therapeutic benefits to ameliorate clinical sequelae associated with AECOPD and comorbidities such as the inclusion of BT and functional training.

The cardiopulmonary exercise test (CPET) is an important physiological investigation that can aid clinicians in their evaluation of exercise intolerance and dyspnea. Maximal oxygen consumption (V˙O2max) is the gold-standard measure of aerobic fitness and is determined by the variables that define oxygen delivery in the Fick equation (V˙O2 = cardiac output × arterial-venous O2 content difference). In healthy subjects, of the variables involved in oxygen delivery, it is the limitations of the cardiovascular system that are most responsible for limiting exercise, as ventilation and gas exchange are sufficient to maintain arterial O2 content up to peak exercise. Patients with lung disease can develop a pulmonary limitation to exercise which can contribute to exercise intolerance and dyspnea. In these patients, ventilation may be insufficient for metabolic demand, as demonstrated by an inadequate breathing reserve, expiratory flow limitation, dynamic hyperinflation, and/or retention of arterial CO2. Lung disease patients can also develop gas exchange impairments with exercise as demonstrated by an increased alveolar-to-arterial O2 pressure difference. CPET testing data, when combined with other clinical/investigation studies, can provide the clinician with an objective method to evaluate cardiopulmonary physiology and determination of exercise intolerance.

The cardiopulmonary exercise test (CPET) is an important physiological investigation that can aid clinicians in their evaluation of exercise intolerance and dyspnea. Maximal oxygen consumption (V˙O2max) is the gold-standard measure of aerobic fitness and is determined by the variables that define oxygen delivery in the Fick equation (V˙O2= cardiac output × arterial-venous O2content difference). In healthy subjects, of the variables involved in oxygen delivery, it is the limitations of the cardiovascular system that are most responsible for limiting exercise, as ventilation and gas exchange are sufficient to maintain arterial O2content up to peak exercise. Patients with lung disease can develop a pulmonary limitation to exercise which can contribute to exercise intolerance and dyspnea. In these patients, ventilation may be insufficient for metabolic demand, as demonstrated by an inadequate breathing reserve, expiratory flow limitation, dynamic hyperinflation, and/or retention of arterial CO2. Lung disease patients can also develop gas exchange impairments with exercise as demonstrated by an increased alveolar-to-arterial O2pressure difference. CPET testing data, when combined with other clinical/investigation studies, can provide the clinician with an objective method to evaluate cardiopulmonary physiology and determination of exercise intolerance.

We examined whether arterial hypoxemia impairs incremental exercise performance in subjects with interstitial lung disease (ILD). Seven subjects underwent two incremental exercise tests on a bicycle ergometer in random order; one while breathing room air (RA), and the other while breathing 60% O2. Maximal exercise performance was impaired in all subjects: maximal oxygen uptake (peak VO2) was 56 +/- 4% predicted (+/- SEM); and all subjects demonstrated significant arterial oxygen desaturation during exercise breathing RA (mean 11 +/- 1%). Breathing 60% O2 during exercise resulted in a significant increase in peak VO2 (RA: 1.32 +/- 0.05 L/min; O2: 1.58 +/- 0.08 L/min; p < 0.05), exercise duration (RA: 390 +/- 21 s; O2: 458 +/- 24 s; p < 0.01) and maximal work load (RA: 112 +/- 6 watts; O2: 129 +/- 6 watts; p < 0.005). There was no significant difference in maximal minute ventilation (VI) achieved at the end of both tests. At matched ventilation (90% peak VI from the RA test), respiratory frequency (f) was significantly higher (RA: 33 +/- 2 breaths/min; O2: 35 +/- 2 breaths/min; p < 0.05), and tidal volume (VT) significantly lower (RA: 1.72 +/- 0.15 L; O2: 1.64 +/- 0.12; p < 0.05) when subjects exercised breathing oxygen. We conclude that arterial hypoxemia significantly impairs incremental exercise performance in subjects with ILD, but that mechanisms other than arterial oxygen desaturation are responsible for the rapid, shallow breathing pattern these subjects adopt during exercise.

Study design We tested the hypothesis that maximal exercise performance in subjects with interstitial lung disease (ILD) is limited by respiratory factors. Assuming this is so, ventilatory stimulation by added dead space (VD) should impair exercise capacity. Methods Six subjects with ILD each underwent three maximal incremental exercise studies on a bicycle ergometer; control 1, added VD, and control 2. During the VD study, external VD (500 ml) was added to the circuit, and results obtained were compared with the mean results from the control studies. Results Exercise duration (TLIM) was significantly less in the VD study when compared to the control study (369 ± 50 vs 439 ± 55, p < 0.05), as was work rate (102 ± 13 vs 125 ± 14 W, p < 0.05) and peak oxygen uptake per minute ( V ˙ o 2 ) (1.08 ± 0.09 vs 1.43 ± 0.14 L/min, p < 0.05). At end-exercise, the Borg scale was higher in the VD study when compared to the control study (6 ± 1 vs 5 ± 1, p < 0.05), while no significant difference in minute ventilation ( V ˙ I) or oxygen desaturation was noted. When compared to the control study at matched times during exercise, the addition of VD resulted in a significant increase in V ˙ while no significant change was noted in V ˙ o 2 , carbon dioxide output ( V ˙ co 2 ), or heart rate (HR). Conclusion The decrease observed in TLIM, work rate, and peak V ˙ o 2 with added VD, associated with a lack of change in V ˙ I or oxygen desaturation at end-exercise, suggests that exercise limitation in ILD isprimarily due to respiratory factors.

This guideline is an official statement of the American College of Physicians (ACP), American College of Chest Physicians (ACCP), American Thoracic Society (ATS), and European Respiratory Society (ERS). It represents an update of the 2007 ACP clinical practice guideline on diagnosis and management of stable chronic obstructive pulmonary disease (COPD) and is intended for clinicians who manage patients with COPD. This guideline addresses the value of history and physical examination for predicting airflow obstruction; the value of spirometry for screening or diagnosis of COPD; and COPD management strategies, specifically evaluation of various inhaled therapies (anticholinergics, long-acting β-agonists, and corticosteroids), pulmonary rehabilitation programs, and supplemental oxygen therapy.This guideline is based on a targeted literature update from March 2007 to December 2009 to evaluate the evidence and update the 2007 ACP clinical practice guideline on diagnosis and management of stable COPD. RECOMMENDATION 1: ACP, ACCP, ATS, and ERS recommend that spirometry should be obtained to diagnose airflow obstruction in patients with respiratory symptoms (Grade: strong recommendation, moderate-quality evidence). Spirometry should not be used to screen for airflow obstruction in individuals without respiratory symptoms (Grade: strong recommendation, moderate-quality evidence). RECOMMENDATION 2: For stable COPD patients with respiratory symptoms and FEV(1) between 60% and 80% predicted, ACP, ACCP, ATS, and ERS suggest that treatment with inhaled bronchodilators may be used (Grade: weak recommendation, low-quality evidence). RECOMMENDATION 3: For stable COPD patients with respiratory symptoms and FEV(1)60% predicted, ACP, ACCP, ATS, and ERS recommend treatment with inhaled bronchodilators (Grade: strong recommendation, moderate-quality evidence). RECOMMENDATION 4: ACP, ACCP, ATS, and ERS recommend that clinicians prescribe monotherapy using either long-acting inhaled anticholinergics or long-acting inhaled β-agonists for symptomatic patients with COPD and FEV(1)60% predicted. (Grade: strong recommendation, moderate-quality evidence). Clinicians should base the choice of specific monotherapy on patient preference, cost, and adverse effect profile. RECOMMENDATION 5: ACP, ACCP, ATS, and ERS suggest that clinicians may administer combination inhaled therapies (long-acting inhaled anticholinergics, long-acting inhaled β-agonists, or inhaled corticosteroids) for symptomatic patients with stable COPD and FEV(1)60% predicted (Grade: weak recommendation, moderate-quality evidence). RECOMMENDATION 6: ACP, ACCP, ATS, and ERS recommend that clinicians should prescribe pulmonary rehabilitation for symptomatic patients with an FEV(1)50% predicted (Grade: strong recommendation, moderate-quality evidence). Clinicians may consider pulmonary rehabilitation for symptomatic or exercise-limited patients with an FEV(1)50% predicted. (Grade: weak recommendation, moderate-quality evidence). RECOMMENDATION 7: ACP, ACCP, ATS, and ERS recommend that clinicians should prescribe continuous oxygen therapy in patients with COPD who have severe resting hypoxemia (Pao(2) ≤55 mm Hg or Spo(2) ≤88%) (Grade: strong recommendation, moderate-quality evidence).

Background Non-adherence rates are high among patients with psoriasis, partly because of discordance between recommended treatments and individual preferences. Objectives Our aim was to assess the impact of comorbidities on patients' preferences for psoriasis treatments. Methods A computer-based conjoint analysis experiment was conducted to analyze preferences of patients with psoriasis (N = 163) for treatment outcome attributes (probability, magnitude and duration of benefit; probability, severity and reversibility of side effects) and process attributes (treatment location, frequency, duration, delivery method, individual cost). The impact of comorbidities (psoriatic arthritis, cardiovascular disease, diabetes, and depression) on relative importance scores of each attribute was assessed by analyses of variance, post hoc test, and multivariate regression analysis. Results Among the participants included (58.9% males, mean age 49.3 yrs), 27% suffered from psoriatic arthritis, 13.5% from cardiovascular disease, 8% from diabetes, and 12.9% from depression. Preferences for treatment attributes varied significantly depending on comorbidities. Participants with psoriatic arthritis cared most about the probability of benefit (β 0.166; P = .037), whereas those participants with cardiovascular disease were highly concerned about the probability of side effects (β 0.179; P = .046). For participants with depression, treatment duration (β 0.163; P = .047), and individual cost ( P = .023) were highly important. Limitations Only patients with moderate and severe psoriasis treated at a university medical center were included. Conclusions Integrating patients' preferences into shared decision-making may facilitate treatment adherence and optimize outcomes. Addressing patients' comorbidities, particularly depression, may be a currently neglected opportunity to improve care.

The ability to engineer interfacial energy offsets in photovoltaic devices is one of the keys to their optimization. Here, we demonstrate that improvements in power conversion efficiency may be attained for ZnO/PbS heterojunction quantum dot photovoltaics through the incorporation of a MoO(3) interlayer between the PbS colloidal quantum dot film and the top-contact anode. Through a combination of current-voltage characterization, circuit modeling, Mott-Schottky analysis, and external quantum efficiency measurements performed with bottom- and top-illumination, these enhancements are shown to stem from the elimination of a reverse-bias Schottky diode present at the PbS/anode interface. The incorporation of the high-work-function MoO(3) layer pins the Fermi level of the top contact, effectively decoupling the device performance from the work function of the anode and resulting in a high open-circuit voltage (0.59 ± 0.01 V) for a range of different anode materials. Corresponding increases in short-circuit current and fill factor enable 1.5-fold, 2.3-fold, and 4.5-fold enhancements in photovoltaic device efficiency for gold, silver, and ITO anodes, respectively, and result in a power conversion efficiency of 3.5 ± 0.4% for a device employing a gold anode.

We fabricate PbS colloidal quantum dot (QD)-based solar cells using a fullerene derivative as the electron-transporting layer (ETL). A thiol treatment and oxidation process are used to modify the morphology and electronic structure of the QD films, resulting in devices that exhibit a fill factor (FF) as high as 62%. We also show that, for QDs with a band gap of less than 1 eV, an open-circuit voltage (VOC) of 0.47 V can be achieved. The power conversion efficiency reaches 1.3% under 1 sun AM1.5 test conditions and 2.4% under monochromatic infrared (lambda=1310 nm) illumination. A consistent mechanism for device operation is developed through a circuit model and experimental measurements, shedding light on new approaches for optimization of solar cell performance by modifying the interface between the QDs and the neighboring charge transport layers.

Background: Individuals engaged in work in intensive animal houses experience some of the highest rates of occupationally related respiratory symptoms. Organic dust and in particular endotoxin has been mostclosely associatedwith respiratorysymptomsand lung function changes in workers. It has previously been shown that for intensive poultryoperations, type of poultry housing [cage-housed (CH) versus floor-housed (FH)] can influence the levels of environmental contaminants. The goal of the study was to determine the differences in endotoxin and dust levels at different size fractions between CH and FH poultry operations. Methods:FifteenCH and15FHpoultryoperations weresampledforstationarymeasurements (area) of dust and associated endotoxin. Fractioned samples were collected utilizing Marple cascade impactors. Gravimetric and endotoxin analysis were conducted on each of the filters. Results: When assessed by individual Marple stage, there was significantly greater airborne endotoxin concentration (endotoxin units per cubic meter) in the size fraction >9.8 mm for the FH operations whereas at the size fraction 1.6‐3.5 mm, the CH operations had significantly greater airborne endotoxin concentration than the FH operations. Endotoxin concentration in the dust mass (endotoxin units per milligram) was significantly greater in the CH operations as compared to the FH operations for all size fractions >1.6 mm. As such, endotoxin in the respirable fraction accounted for 24% of the total endotoxin in the CH operations whereas it accounted for only 11% in the FH operations. There was significantly more dust in all size fractions in the FH operations as compared to the CH poultry operations. Conclusions: There is more endotoxin in the presence of significantly lower dust levels in the respirable particle size fractions in CH poultry operations as compared to the FH poultry operations. This difference in respirable endotoxin may be important in relation to the differential respiratory response experienced by CH and FH poultry operation workers.

A B S T R A C T Introduction: Respiratory illness is a leading cause of death worldwide, with rates that will continue to escalate into the foreseeable future. Rural residents have an increased risk of dying from some forms of respiratory disease, although little is known about the healthcare utilization or location of death for persons with advanced respiratory illness in rural settings. The purpose of this study was to examine rural-urban differences in healthcare utilization and location of death for residents of Saskatchewan, Canada, with chronic obstructive pulmonary disease (COPD) or lung cancer in the last 12 months of life. Methods: A retrospective cohort study was undertaken of 1098 patients who died in 2004 with a cause of death recorded as COPD or lung cancer in administrative health data from Saskatchewan Health. Decedents were classified as residents of rural/remote ( �9,999 population size), small urban or urban ( �100 000) locations and analysis conducted using this primary variable of interest. Comparisons were made between the three groups in terms of demographic characteristics, healthcare utilization (physician visits, length of stay, hospitalizations, institutional care, home care, transitions between care settings) and location of death (hospital, long-term care (LTC) or home). Results: The study population was 57% male with a mean age of 77 years (SD=11). Demographic characteristics, underlying cause of death and number of comorbid conditions were similar between urban, small urban and rural/remote groups. After

Donna Goodridge1, Josh Lawson2, Graeme Rocker3, Darcy Marciniuk4, Donna Rennie1,21College of Nursing, 2Canadian Centre for Health and Safety in Agriculture, University of Saskatchewan, Saskatoon, Saskatchewan, Canada; 3Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada; 4College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, CanadaBackground: For patients in late stages of chronic obstructive pulmonary disease (COPD), dyspnea is often refractory to conventional treatment. We know little about the use of opioids in ameliorating dyspnea in this population. In this study we explored factors associated with opioid dispensation within the last year of life and differences in opioid dispensation for persons with lung cancer or COPD.Methods: In this retrospective cohort study we used administrative health data gained from 1,035 residents of Saskatchewan, Canada to examine patterns of community opioid dispensation in the last year of life. Factors associated with opioid use were determined using multiple logistic regression.Results: When compared with those with lung cancer, fewer patients with COPD were given opioids within the last week of life; the last month of life, and the last 3 months of life. After adjusting for relevant predictors, patients with lung cancer were more than twice as likely as those with COPD to fill prescriptions for the following: morphine (odds ratio [OR] 2.36, 95% confidence interval [CI]: 1.52–3.67); hydromorphone (OR 2.69, 95% CI: 1.53–4.72); transdermal fentanyl (OR 2.25, 95% CI: 1.28–3.98); or any of these opioids (OR 2.61, 95% CI: 1.80–3.80).Conclusion: These opioids are dispensed only for a small proportion of patients with COPD at the end of their lives. Future researchers could explore the efficacy and safety of opioid use for patients with advanced COPD, and whether their limited use is justified.Keywords: COPD, lung cancer, dyspnea, opioid dispensation, palliative care

Fumonisins are mycotoxins produced by strains belonging to several different mating populations of Gibberella fujikuroi (anamorphs, Fusarium section Liseola), a major pathogen of maize and sorghum worldwide. We studied the heritability of fumonisin production in mating population A by crossing fumonisin-producing strains collected from maize and sorghum in the United States with fumonisin-nonproducing strains collected from maize in Nepal. Random ascospore and tetrad progeny from three of these crosses were analyzed by gas chromatography-mass spectrometry and high-performance liquid chromatography for their ability to produce fumonisins on autoclaved cracked maize. In all three crosses, the ability to produce fumonisins, predominately fumonisin B1, segregated as a single gene or group of closely linked genes. Intercrosses between appropriate progeny and parents were poorly fertile, so we could not determine if the apparent single genes that were segregating in each of these crosses were allelic with one another. Mating type and spore-killer traits were scored in some crosses, and each segregated, as expected, as a single gene that was unlinked to the ability to produce fumonisins. We conclude that G. fujikuroi mating population A provides a powerful genetic system for the study of this important fungal toxin.

Protamine sulfate (PS), used to neutralize the anticoagulant effect of heparin, is often associated with systemic hypotension. Whether this hypotension is secondary to a depression of myocardial function is not clear. The present study tested the hypothesis that systemic hypotension was accompanied by a depression in myocardial function and examined the possible role of histamine in mediating the cardiovascular response to PS. Seven conditioned dogs were chronically instrumented with pressure and ultrasonic dimension transducers. Studies were conducted under halothane anesthesia 7 to 10 days after instrumentation. Cardiac contractility was assessed using the slope, Ees, of the linear regression of the left ventricular end-systolic pressure-diameter relationship. Intravenous infusion of PS, 5 mg/kg, when given in periods of less than 30 seconds, decreased systemic arterial pressure by 45% (from 101 +/- to 54 +/- 5 mm Hg) without change in heart rate. Cardiac output decreased by 22% from control and the slope Ees decreased by 37% (from 14.5 +/- 1.2 to 8.7 +/- 1.4 mm Hg/mm). Systemic vascular resistance decreased by 34% (from 2581 +/- 121 to 1712 +/- 200 dyne.s.cm-5). The cardiovascular depression caused by PS was transient and could not be reproduced by a repeated dose given within a 60-minute period. Antagonists of histamine (diphenhydramine and cimetidine) could not attenuate the PS-induced cardiovascular depression. This depression was independent of preheparinization and did not occur when PS was infused slowly over a 2-minute period. The data clearly demonstrate negative inotropic and vasodilator effects of PS following rapid administration.(ABSTRACT TRUNCATED AT 250 WORDS)

A new fumonisin has been isolated from Fusarium moniliforme isolate MRC826 grown on corn. It was shown by NMR and mass spectrometry to be an isomer of fumonisin B2 that has free hydroxyl groups at C-3 and C-10 instead of the normal C-3 and C-5. This new fumonisin was detected in cultures of most isolates of F. moniliforme that were examined and was usually present at concentrations similar to those of fumonisin B2. Two isolates of F. moniliforme that produce significantly higher levels of this new isomer were identified.

La introduccion in vitro de tejido adulto de nogal (Juglans regia L.) representa una oportunidad de clonacion de genotipos elite, cuya seleccion ocurre en estados ontogenicos avanzados. Asi, con el objeto de desarrollar un protocolo que permita la propagacion masiva de genotipos valiosos a partir de material adulto, se compararon dos sistemas de induccion rizogenica de microtallos de nogal provenientes del cuarto subcultivo de un programa de introduccion in vitro de tejido adulto de nogal, previamente revigorizado mediante injerto tradicional. Se utilizo la induccion rizogenica por acido indol-3-butirico (AIB) y Agrobacterium rhizogenes. El proceso rizogenico se analizo tanto para induccion auxinica (T1: 3 mg L-1 AIB; T2: 5 mg L-1 AIB), como para induccion por A. rhizogenes (T3: A-477; T4: A-478), en dos fases. Una primera fase de induccion radicular, con una duracion de 3 dias en oscuridad; y una segunda fase de 27 dias, denominada de manifestacion radicular. En todos los tratamientos se evaluo porcentaje de enraizamiento y se caracterizaron los sistemas radiculares inducidos (numero, largo, diametro y zona de insercion de raices). Los mejores resultados de enraizamiento se obtuvieron en T2; sin embargo, la respuesta obtenida con A. rhizogenes no difiere de aquella lograda en T1, por lo que pareciera ser una metodologia de creciente interes para la rizogenesis adventicia en esta especie.