scholarly journals Dyspnea, effort and muscle pain during exercise in lung transplant recipients: an analysis of their association with cardiopulmonary function parameters using machine learning

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Fausto Braccioni ◽  
Daniele Bottigliengo ◽  
Andrea Ermolao ◽  
Marco Schiavon ◽  
Monica Loy ◽  
...  
Keyword(s):  
Machine Learning ◽  
Exercise Testing ◽  
Subgroup Analysis ◽  
Muscle Pain ◽  
Lung Transplant ◽  
Minute Ventilation ◽  
Peak Exercise ◽  
Peripheral Muscle ◽  
Arterial Blood ◽  
Dyspnea Score

Abstract Background Despite improvement in lung function, most lung transplant (LTx) recipients show an unexpectedly reduced exercise capacity that could be explained by persisting peripheral muscle dysfunction of multifactorial origin. We analyzed the course of symptoms, including dyspnea, muscle effort and muscle pain and its relation with cardiac and pulmonary function parameters during an incremental exercise testing. Methods Twenty-four bilateral LTx recipients were evaluated in an observational cross-sectional study. Recruited patients underwent incremental cardio-pulmonary exercise testing (CPET). Arterial blood gases at rest and peak exercise were measured. Dyspnea, muscle effort and muscle pain were scored according to the Borg modified scale. Potential associations between the severity of symptoms and exercise testing parameters were analyzed using a Forest-Tree Machine Learning approach, which accomplishes for a ratio between number of observations and number of screened variables less than unit. Results Dyspnea score was significantly associated with maximum power output (WR, watts), and minute ventilation (VE, L/min) at peak exercise. In a controlled subgroup analysis, dyspnea score was a limiting symptom only in LTx recipients who reached the higher levels of WR (≥ 101 watts) and VE (≥ 53 L/min). Muscle effort score was significantly associated with breathing reserve as percent of maximal voluntary ventilation (BR%MVV). The lower the BR%MVV at peak exercise (< 32) the higher the muscle effort perception. Muscle pain score was significantly associated with VO2 peak, arterial [HCO3−] at rest, and VE/VCO2 slope. In a subgroup analysis, muscle pain was the limiting symptom in LTx recipients with a lower VO2 peak (< 15 mL/Kg/min) and a higher VE/VCO2 slope (≥ 32). Conclusions The majority of our LTx recipients reported peripheral limitation as the prevalent reason for exercise termination. Muscle pain at peak exercise was strictly associated with basal and exercise-induced metabolic altered pathways. The onset of dyspnea (breathing effort) was associated with the intensity of ventilatory response to meet metabolic demands for increasing WR. Our study suggests that only an accurate assessment of symptoms combined with cardio-pulmonary parameters allows a correct interpretation of exercise limitation and a tailored exercise prescription. The role and mechanisms of muscle pain during exercise in LTx recipients requires further investigations.

Exercise, potassium, and muscle deconditioning post-thoracic organ transplantation

1994 ◽  
Vol 77 (6) ◽  
pp. 2784-2790 ◽  
Author(s):  
M. J. Hall ◽  
G. I. Snell ◽  
E. A. Side ◽  
D. S. Esmore ◽  
E. H. Walters ◽  
...  
Keyword(s):  
Organ Transplantation ◽  
Healthy Subjects ◽  
Lung Transplant ◽  
Peak Plasma ◽  
Peak Oxygen Consumption ◽  
Peak Exercise ◽  
Arterial Blood ◽  
Graded Exercise ◽  
K Concentration ◽  
Thoracic Organ

Although muscle deconditioning appears to significantly limit peak exercise performance post-thoracic organ transplantation, few confirmatory data exist. Potassium (K+) regulation during exercise may reflect muscle deconditioning, since both peak plasma K+ concentration ([K+]) and the increase in plasma [K+] relative to energy expenditure (delta [K+]/W) are reduced in healthy individuals after training. This study compares delta [K+]/W during graded exercise and the change in [K+] (delta [K+]) during both exercise and recovery in 12 heart transplant (HT) recipients, 14 lung transplant (LT) recipients, and 7 healthy subjects. Plasma [K+] was determined from arterial blood sampled at rest; during the final 15 s of each power output; and at 1, 2, and 5 min postexercise. Peak oxygen consumption was significantly lower (P < 0.0001), whereas delta [K+]/W was significantly higher (P < 0.002) among the HT and LT groups. When delta [K+] during recovery was expressed relative to delta [K+] detected during activity, no difference at 1, 2, or 5 min postexercise was detected, although the absolute fall in plasma [K+] was greater among the healthy subjects in the 1st min (P < 0.0001). The rate of delta [K+] during recovery appears to reflect the rise seen during activity in all groups. These results suggest that [K+] regulation is altered during exercise in both HT and LT recipients and may reflect muscle deconditioning.

Ventilatory failure during loaded breathing: the role of central neural drive

1988 ◽  
Vol 65 (1) ◽  
pp. 249-255 ◽  
Author(s):  
J. F. Watchko ◽  
T. A. Standaert ◽  
D. E. Mayock ◽  
G. Twiggs ◽  
D. E. Woodrum
Keyword(s):  
Minute Ventilation ◽  
Respiratory Muscles ◽  
Muscle Performance ◽  
Emg Activity ◽  
Base Line ◽  
Force Frequency ◽  
Peripheral Muscle ◽  
Arterial Blood ◽  
Loaded Breathing ◽  
Ventilatory Failure

Minute ventilation (VE), arterial blood gases, diaphragmatic electromyogram (EMG) activity, centroid frequency (Fc) and peak inspiratory airway pressures (Paw) were measured in five unanesthetized tracheostomized infant monkeys during various intensities of inspiratory resistive loaded breathing (IRL) until either 1) ventilatory failure occurred (failed trial) or 2) normocapnia was sustained for 1 h (successful trial). During successful trials VE and arterial PCO2 (PaCO2) were sustained at base-line levels, and an increase in peak integrated diaphragmatic EMG activity and peak inspiratory Paw occurred. In contrast, during ventilatory failure runs, VE decreased and PaCO2 rose compared with their respective base-line values. The fall in VE occurred secondary to a significant decline in breathing frequency. Tidal volume was sustained at base-line levels during all trials (both successful and failed groups). Inspiratory Paw's and peak moving time average EMG were sustained at elevated levels during ventilatory failure runs, suggesting that the respiratory muscles did not fail as pressure generators. Furthermore, the EMG Fc did not change from base line during either successful or failed trials. These data suggest that peripheral muscle fatigue did not occur, although in the absence of a more direct test of muscle performance, i.e., a force-frequency curve, we cannot rule out the possibility that a component of peripheral failure contributed to our results. Ventilatory failure during severe IRL in the infant monkey was most clearly associated with an alteration in the respiratory center timing mechanism, i.e., such failure was a function of a decline in respiratory frequency.

scholarly journals Reference Values and Predictive Equations for Cardiopulmonary Exercise Testing in Thai Adults

2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Prapaporn Pornsuriyasak ◽  
Kitipong Ngaojaruwong ◽  
Suchada Saovieng ◽  
Jayanton Patumanond ◽  
Khanat Kruthkul ◽  
...  
Keyword(s):  
Physical Activity ◽  
Exercise Testing ◽  
Minute Ventilation ◽  
Cardiopulmonary Exercise Testing ◽  
Activity Level ◽  
Screening Tests ◽  
Peak Exercise ◽  
Predictive Equations ◽  
Cardiopulmonary Exercise ◽  
History Of

Background: A series of racial specific predictive equations for exercise parameters are needed to determine a lack of cardiopulmonary fitness or having an exercise limitation on cardiopulmonary exercise testing (CPET). Objectives: The study aimed to develop a new set of predictive equations of CPET parameters during maximal cycling exercise for Thai adults. Methods: A sample of 580 Thai adults whom could pass screening tests were asked to fill a health questionnaire and the Global Physical Activity questionnaire. Participants with history of symptomatic heart and pulmonary diseases, current smokers, history of smoking ≥ 10 pack-years, and abnormal spirometry were excluded. The CPET was performed using a cycle ergometer with an incremental symptom-limited protocol. Values of CPET parameters at the peak exercise (oxygen uptake [V̇O2], work rate, heart rate, oxygen pulse, and minute ventilation), lactic acidosis threshold, and ventilatory equivalents for oxygen and carbon dioxide were documented. Analyses were stratified using age and gender criterion. Predictive equations for CPET parameters were established using multivariable linear regression with age (A), weight (W), height (H), and physical activity level (Act) as independent variables. Results: A total of 493 participants (208 men and 285 women) were analysed. The predictive equation of V̇O2peak (L.min-1) for males was: -2.268 + (0.037 × A) - (0.0005 × A2) + (0.016 × W) + (0.014 × H) + (0.104 × Act), (R2 = 0.41, SEE = 0.392), and for females, it was: -0.34 + (0.009 × A) - (0.0002 × A2) + (0.012 × W) + (0.005 × H) + (0.058 × Act), (R2 = 0.44, SEE = 0.220). Conclusions: This is the first study that constructed the predictive equations for cycling CPET parameters in Thai adults. These equations are useful to evaluate the cardiopulmonary health of the Thai population and may be generalized to other populations with geographical or ethnic proximity to the Thai people.

Ventilatory and metabolic adaptations to walking and cycling in patients with COPD

2000 ◽  
Vol 88 (5) ◽  
pp. 1715-1720 ◽  
Author(s):  
Paolo Palange ◽  
Silvia Forte ◽  
Paolo Onorati ◽  
Felice Manfredi ◽  
Pietro Serra ◽  
...  
Keyword(s):  
Minute Ventilation ◽  
Venous Blood ◽  
Blood Gases ◽  
Peak Exercise ◽  
Chronic Obstructive ◽  
Arterial Blood Gases ◽  
Physiological Dead Space ◽  
Arterial Blood ◽  
Ergometer Exercise ◽  
Walking Capacity

To test the hypothesis that in chronic obstructive pulmonary disease (COPD) patients the ventilatory and metabolic requirements during cycling and walking exercise are different, paralleling the level of breathlessness, we studied nine patients with moderate to severe, stable COPD. Each subject underwent two exercise protocols: a 1-min incremental cycle ergometer exercise (C) and a “shuttle” walking test (W). Oxygen uptake (V˙o 2), CO2output (V˙co 2), minute ventilation (V˙e), and heart rate (HR) were measured with a portable telemetric system. Venous blood lactates were monitored. Measurements of arterial blood gases and pH were obtained in seven patients. Physiological dead space-tidal volume ratio (Vd/Vt) was computed. At peak exercise, W vs. CV˙o 2,V˙e, and HR values were similar, whereasV˙co 2 (848 ± 69 vs. 1,225 ± 45 ml/min; P < 0.001) and lactate (1.5 ± 0.2 vs. 4.1 ± 0.2 meq/l; P < 0.001) were lower, ΔV˙e/ΔV˙co 2(35.7 ± 1.7 vs. 25.9 ± 1.3; P < 0.001) and ΔHR/ΔV˙o 2values (51 ± 3 vs. 40 ± 4; P < 0.05) were significantly higher. Analyses of arterial blood gases at peak exercise revealed higher Vd/Vt and lower arterial partial pressure of oxygen values for W compared with C. In COPD, reduced walking capacity is associated with an excessively high ventilatory demand. Decreased pulmonary gas exchange efficiency and arterial hypoxemia are likely to be responsible for the observed findings.

Cardiopulmonary Exercise Testing in Combined Pulmonary Fibrosis and Emphysema

Respiration ◽  
2021 ◽  
pp. 369-377
Author(s):  
Michael Westhoff ◽  
Patric Litterst ◽  
Ralf Ewert
Keyword(s):  
Body Weight ◽  
Pulmonary Fibrosis ◽  
Sensitivity And Specificity ◽  
Exercise Testing ◽  
Cardiopulmonary Exercise Testing ◽  
Arterial Oxygen ◽  
Peak Exercise ◽  
Cutoff Value ◽  
Cardiopulmonary Exercise ◽  
Peak Vo2

Background: Combined pulmonary fibrosis and emphysema (CPFE) is a distinct entity among fibrosing lung diseases with a high risk for lung cancer and pulmonary hypertension (PH). Notably, concomitant PH was identified as a negative prognostic indicator that could help with early diagnosis to provide important information regarding prognosis. Objectives: The current study aimed to determine whether cardiopulmonary exercise testing (CPET) can be helpful in differentiating patients having CPFE with and without PH. Methods: Patients diagnosed with CPFE in 2 German cities (Hemer and Greifswald) over a period of 10 years were included herein. CPET parameters, such as peak oxygen uptake (peak VO2), functional dead space ventilation (VDf/VT), alveolar-arterial oxygen difference (AaDO2), arterial-end-tidal CO2 difference [P(a-ET)CO2] at peak exercise, and the minute ventilation-carbon dioxide production relationship (VE/VCO2 slope), were compared between patients with and without PH. Results: A total of 41 patients with CPET (22 with PH, 19 without PH) were analyzed. Right heart catheterization was performed in 15 of 41 patients without clinically relevant complications. Significant differences in peak VO2 (861 ± 190 vs. 1,397 ± 439 mL), VO2/kg body weight/min (10.8 ± 2.6 vs. 17.4 ± 5.2 mL), peak AaDO2 (72.3 ± 7.3 vs. 46.3 ± 14.2 mm Hg), VE/VCO2 slope (70.1 ± 31.5 vs. 39.6 ± 9.6), and peak P(a-ET)tCO2 (13.9 ± 3.5 vs. 8.1 ± 3.6 mm Hg) were observed between patients with and without PH (p < 0.001). Patients with PH had significantly higher VDf/VT at rest, VT1, and at peak exercise (65.6 ± 16.8% vs. 47.2 ± 11.6%; p < 0.001) than those without PH. A cutoff value of 44 for VE/VCO2 slope had a sensitivity and specificity of 94.7 and 72.7%, while a cutoff value of 11 mm Hg for P(a-ET)CO2 in combination with peak AaDO2 >60 mm Hg had a specificity and sensitivity of 95.5 and 84.2%, respectively. Combining peak AaDO2 >60 mm Hg with peak VO2/body weight/min <16.5 mL/kg/min provided a sensitivity and specificity of 100 and 95.5%, respectively. Conclusion: This study provided initial data on CPET among patients having CPFE with and without PH. CPET can help noninvasively detect PH and identify patients at risk. AaDO2 at peak exercise, VE/VCO2 slope, peak P(a-ET)CO2, and peak VO2 were parameters that had high sensitivity and, when combined, high specificity.

scholarly journals Supervised Machine Learning Methods and Hyperspectral Imaging Techniques Jointly Applied for Brain Cancer Classification

Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3827
Author(s):  
Gemma Urbanos ◽  
Alberto Martín ◽  
Guillermo Vázquez ◽  
Marta Villanueva ◽  
Manuel Villa ◽  
...  
Keyword(s):  
Machine Learning ◽  
Blood Vessel ◽  
Hyperspectral Imaging ◽  
Imaging Techniques ◽  
Venous Blood ◽  
Healthy Tissue ◽  
Supervised Machine Learning ◽  
Support Vector ◽  
Arterial Blood

Hyperspectral imaging techniques (HSI) do not require contact with patients and are non-ionizing as well as non-invasive. As a consequence, they have been extensively applied in the medical field. HSI is being combined with machine learning (ML) processes to obtain models to assist in diagnosis. In particular, the combination of these techniques has proven to be a reliable aid in the differentiation of healthy and tumor tissue during brain tumor surgery. ML algorithms such as support vector machine (SVM), random forest (RF) and convolutional neural networks (CNN) are used to make predictions and provide in-vivo visualizations that may assist neurosurgeons in being more precise, hence reducing damages to healthy tissue. In this work, thirteen in-vivo hyperspectral images from twelve different patients with high-grade gliomas (grade III and IV) have been selected to train SVM, RF and CNN classifiers. Five different classes have been defined during the experiments: healthy tissue, tumor, venous blood vessel, arterial blood vessel and dura mater. Overall accuracy (OACC) results vary from 60% to 95% depending on the training conditions. Finally, as far as the contribution of each band to the OACC is concerned, the results obtained in this work are 3.81 times greater than those reported in the literature.

Dietary effects on exercising muscle metabolism and performance by 31P-MRS

1994 ◽  
Vol 77 (3) ◽  
pp. 1108-1115 ◽  
Author(s):  
D. E. Larson ◽  
R. L. Hesslink ◽  
M. I. Hrovat ◽  
R. S. Fishman ◽  
D. M. Systrom
Keyword(s):  
Minute Ventilation ◽  
Muscle Metabolism ◽  
Exercise Duration ◽  
Quadriceps Muscle ◽  
Peak Exercise ◽  
Crossover Fashion ◽  
Resonance Spectroscopy ◽  
Phosphorylation Potential ◽  
Beneficial Effects ◽  
Muscle Ph

To determine how diet modulates short-term exercise capacity, skeletal muscle pH and bioenergetic state were examined by 31P-magnetic resonance spectroscopy in nine healthy volunteers. Subjects performed incremental quadriceps exercise to exhaustion after 5 days of high-carbohydrate (HCHO) or high-fat (HFAT) diet randomly assigned in crossover fashion and separated by a 2.5-day period of ad libitum mixed diet. Simultaneous measurements were made of pulmonary gas exchange, minute ventilation, and quadriceps muscle pH and phosphorylation potential. At rest and peak exercise, respiratory exchange ratio and minute ventilation were higher after HCHO than after HFAT (P < 0.05), reflecting greater CHO utilization. Peak O2 consumption (VO2) was not increased after HCHO (P > 0.05), but exercise duration was (339 +/- 34 s for HCHO vs. 308 +/- 25 s for HFAT; P < 0.05). HCHO was associated with a blunted early fall of phosphocreatine (PCr)/Pi vs. VO2 (-4.1 +/- 0.7 x 10(-2) min/ml for HCHO vs. -5.6 +/- 1.2 x 10(-2) min/ml for HFAT; P < 0.05). On both study days, the slope of PCr/Pi vs. VO2, before and after the PCr threshold, was correlated with exercise time. The results suggest that a diet rich in CHO improves exercise efficiency through beneficial effects on intracellular phosphorylation potential.

scholarly journals Radiomics side experiments and DAFIT approach in identifying pulmonary hypertension using Cardiac MRI derived radiomics based machine learning models

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sarv Priya ◽  
Tanya Aggarwal ◽  
Caitlin Ward ◽  
Girish Bathla ◽  
Mathews Jacob ◽  
...  
Keyword(s):  
Machine Learning ◽  
Pulmonary Hypertension ◽  
Feature Selection ◽  
Subgroup Analysis ◽  
Cardiac Mri ◽  
Intraclass Correlation ◽  
Poor Performance ◽  
Superior Performance ◽  
Feature Filtering ◽  
The Impact

AbstractSide experiments are performed on radiomics models to improve their reproducibility. We measure the impact of myocardial masks, radiomic side experiments and data augmentation for information transfer (DAFIT) approach to differentiate patients with and without pulmonary hypertension (PH) using cardiac MRI (CMRI) derived radiomics. Feature extraction was performed from the left ventricle (LV) and right ventricle (RV) myocardial masks using CMRI in 82 patients (42 PH and 40 controls). Various side study experiments were evaluated: Original data without and with intraclass correlation (ICC) feature-filtering and DAFIT approach (without and with ICC feature-filtering). Multiple machine learning and feature selection strategies were evaluated. Primary analysis included all PH patients with subgroup analysis including PH patients with preserved LVEF (≥ 50%). For both primary and subgroup analysis, DAFIT approach without feature-filtering was the highest performer (AUC 0.957–0.958). ICC approaches showed poor performance compared to DAFIT approach. The performance of combined LV and RV masks was superior to individual masks alone. There was variation in top performing models across all approaches (AUC 0.862–0.958). DAFIT approach with features from combined LV and RV masks provide superior performance with poor performance of feature filtering approaches. Model performance varies based upon the feature selection and model combination.

scholarly journals Cardiopulmonary Exercise Testing to Assess Persistent Symptoms at 6 Months in People With COVID-19 Who Survived Hospitalization – A Pilot Study

2021 ◽  
Author(s):  
David Debeaumont ◽  
Fairuz Boujibar ◽  
Eglantine Ferrand-Devouge ◽  
Elise Artaud-Macari ◽  
Fabienne Tamion ◽  
...  
Keyword(s):  
Pilot Study ◽  
Physical Fitness ◽  
Exercise Testing ◽  
Cardiopulmonary Exercise Testing ◽  
Respiratory Muscle Training ◽  
Persistent Symptoms ◽  
Cardiopulmonary Exercise ◽  
Rehabilitation Intervention ◽  
Physical Limitations ◽  
Dyspnea Score

Abstract Objective The aim of this pilot study was to assess physical fitness and its relationship with functional dyspnea in survivors of Covid-19, 6 months after their discharge from the hospital. Methods Data collected routinely from people referred for cardiopulmonary exercise testing (CPET) following hospitalization for Covid-19 were retrospectively analyzed. Persistent dyspnea was assessed using the modified Medical Research Council dyspnea (mMRC) scale. Results Twenty-three people with persistent symptoms were referred for CPET. Mean mMRC dyspnea score was 1 (SD = 1) and was significantly associated with VO2peak (%) (rho = −0.49). At 6 months, those hospitalized in the general ward had a slightly reduced VO2peak (87% [SD = 20]), whereas those who had been in the intensive care unit (ICU) had a moderately reduced VO2peak (77% [SD = 15]). Of note, the results of the CPET revealed that, in all patients, respiratory equivalents were high, power-to-weight ratios were low, and those who had been in the ICU had a relatively low ventilatory efficiency (mean VE/VCO2 slope = 34 [SD = 5]). Analysis of each individual showed that none had a breathing reserve &lt;15% or 11 L/min, all had a normal exercise electrocardiogram, and 4 had a heart rate above 90%. Conclusion At 6 months, persistent dyspnea was associated with reduced physical fitness. This study offers initial insights into the mid-term physical fitness of people who required hospitalization for Covid-19. It also provides novel pathophysiological clues about the underlaying mechanism of the physical limitations associated with persistent dyspnea. Those with persistent dyspnea should be offered a tailored rehabilitation intervention, which should probably include muscle reconditioning, breathing retraining, and perhaps respiratory muscle training. Impact This study is the first to show that a persistent breathing disorder (in addition to muscle deconditioning) can explain persistent symptoms 6 months after hospitalization for Covid-19 infection and suggests that a specific rehabilitation intervention is warranted.

Abstract 13745: Severity of Functional Mitral Regurgitation During Maximal Exercise Testing in Heart Failure: Additional Value of Combining Echocardiography with Cardiopulmonary Exercise Testing

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Greta Generati ◽  
Francesco Bandera ◽  
Marta Pellegrino ◽  
Valentina Labate ◽  
Eleonora Alfonzetti ◽  
...  
Keyword(s):  
Heart Failure ◽  
Mitral Regurgitation ◽  
Ejection Fraction ◽  
Exercise Testing ◽  
Cardiopulmonary Exercise Testing ◽  
Functional Mitral Regurgitation ◽  
Peak Exercise ◽  
Cardiopulmonary Exercise ◽  
Pulmonary Hemodynamic ◽  
Increased Risk

Background: In heart failure (HF) patients the severity of mitral regurgitation (MR) at rest has a well established prognostic value and its increase during exercise further adds to an increased risk. Our goal was to define the relationship between the degree of exercise MR severity with cardiopulmonary and echocardiographic related phenotypes in a cohort of HF patients. Methods: 71 HF reduced ejection fraction patients (mean age 67±11; male 72%; ischemic etiology 61%; NYHA class I, II, III and IV 13%, 36%, 39% and 12%, mean ejection fraction 33±9%) underwent cardiopulmonary exercise test (CPET) on tiltable cycle-ergometer combined with echocardiography at rest and during exercise. The population was divided into two groups according to the degree of functional peak MR: no to mild/moderate MR (no MR, MR1+ and MR2+) vs moderate/severe MR (MR3+ and MR4+). Results: A good correlation (ρ coefficient= 0.49) was found between the degree of dynamic MR and PASP at peak exercise. Despite similar echocardiographic profile at rest patients with significant peak MR (MR≥3+) had worse exercise performance (lower peak VO2, O2 pulse and workload) and impaired ventilatory efficiency (higher VE/VCO2 slope). Conclusions: In HF patients the severity of exercise-induced MR is associated with the most unfavorable performance and pulmonary hemodynamic response. A combined approach with CPET and echocardiographic assessment can help to early unmask and target functional MR and its related unfavorable phenotypes.

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