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OBJECTIVE: High-resolution manometry (HRM) is the current standard for characterization of esophageal body and esophagogastric junction (EGJ) function. We aimed to examine the prevalence of abnormal esophageal motor patterns in health, and to determine optimal thresholds for software metrics across HRM systems. DESIGN: Manometry studies from asymptomatic adults were solicited from motility centers worldwide, and were manually analyzed using integrated relaxation pressure (IRP), distal latency (DL), and distal contractile integral (DCI) in standardized fashion. Normative thresholds were assessed using fifth and/or 95th percentile values. Chicago Classification v3.0 criteria were applied to determine motor patterns across HRM systems, study positions (upright vs supine), ages, and genders. RESULTS: Of 469 unique HRM studies (median age 28.0, range 18-79 years). 74.6% had a normal HRM pattern; none had achalasia. Ineffective esophageal motility (IEM) was the most frequent motor pattern identified (15.1% overall), followed by EGJ outflow obstruction (5.3%). Proportions with IEM were lower using stringent criteria (10.0%), especially in supine studies (7.1%-8.5%). Other motor patterns were rare (0.2%-4.1% overall) and did not vary by age or gender. DL thresholds were close to current norms across HRM systems, while IRP thresholds varied by HRM system and study position. Both fifth and 95th percentile DCI values were lower than current thresholds, both in upright and supine positions. CONCLUSIONS: Motor abnormalities are infrequent in healthy individuals and consist mainly of IEM, proportions of which are lower when using stringent criteria in the supine position. Thresholds for HRM metrics vary by HRM system and study position.

Esophageal hypomotility disorders manifest with abnormal esophageal body contraction vigor, breaks in peristaltic integrity, or failure of peristalsis in the context of normal lower esophageal sphincter relaxation on esophageal high-resolution manometry (HRM). The Chicago Classification version 4.0 recognizes two hypomotility disorders, ineffective esophageal motility (IEM) and absent contractility, while fragmented peristalsis has been incorporated into the IEM definition. Updated criteria for ineffective swallows consist of weak esophageal body contraction vigor measured using distal contractile integral (DCI, 100-450 mmHg·cm·s), transition zone defects >5 cm measured using a 20 mmHg isobaric contour, or failure of peristalsis (DCI < 100 mmHg·cm·s). More than 70% ineffective swallows and/or ≥50% failed swallows are required for a conclusive diagnosis of IEM. When the diagnosis is inconclusive (50%-70% ineffective swallows), supplementary evidence from multiple rapid swallows (absence of contraction reserve), barium radiography (abnormal bolus clearance), or HRM with impedance (abnormal bolus clearance) could support a diagnosis of IEM. Absent contractility requires 100% failed peristalsis, consistent with previous versions of the classification. Consideration needs to be given for the possibility of achalasia in absent contractility with dysphagia despite normal IRP, and alternate complementary tests (including timed upright barium esophagram and functional lumen imaging probe) are recommended to confirm or refute the presence of achalasia. Future research to quantify esophageal bolus retention on stationary HRM with impedance and to understand contraction vigor thresholds that predict bolus clearance will provide further refinement to diagnostic criteria for esophageal hypomotility disorders in future iterations of the Chicago Classification.

Introduction Grading dysphagia is crucial for clinical management of patients. The Eckardt score (ES) is the most commonly used for this purpose. We aimed to compare the ES with the recently developed Brief Esophageal Dysphagia Questionnaire (BEDQ) in terms of their correlation and discriminative capacity for clinical and manometric findings and evaluate the effect of gastroesophageal reflux symptoms on both. Methods Symptomatic patients referred for high-resolution manometry (HRM) were prospectively recruited from seven centers in Spain and Latin America. Clinical data and several scores (ES, BEDQ, GERDQ) were collected and contrasted to HRM findings. Standard statistical analysis was performed. Key Results 426 patients were recruited, 31.2% and 41.5% being referred exclusively for dysphagia and GERD symptoms, respectively. Both BEDQ and ES were independently associated with achalasia. Only BEDQ was independently associated with being referred for dysphagia and with relevant HRM findings. ROC curve analysis for achalasia diagnosis showed AUC of 0.809 for BEDQ and 0.765 for ES, with the main difference being higher BEDQ sensitivity (80.0% vs 70.8% for ES). GERDQ independently predicted ES but not BEDQ. In the absence of dysphagia (BEDQ = 0), GERD symptoms significantly determine ES. Conclusions and Inferences Our study suggests both the BEDQ and ES can complementarily describe symptomatic burden in achalasia. BEDQ has several advantages over the ES in the dysphagia evaluation, basically due to its higher sensitivity for manometric diagnosis and independence of GERD symptoms. ES should be used as an achalasia-specific metric, while BEDQ is a better symptom-generic evaluating tool.

BACKGROUND High-resolution impedance manometry (HRIM) evaluates esophageal peristalsis and bolus transit. We used esophageal impedance integral (EII), the ratio between bolus presence before and after an expected peristaltic wave, to evaluate predictors of bolus transit. METHODS From HRIM studies performed on 61 healthy volunteers (median age 27 years, 48%F), standard metrics were extracted from each of 10 supine water swallows: distal contractile integral (DCI, mmHg cm s), integrated relaxation pressure (IRP, mmHg), and breaks in peristaltic integrity (cm, using 20 mmHg isobaric contour). Pressure and impedance coordinates for each swallow were exported into a dedicated, python-based program for EII calculation (EII ratio ≥ 0.3 = abnormal bolus clearance). Univariate and multivariate analyses were performed to assess predictors of abnormal bolus clearance. KEY RESULTS Of 591 swallows, 80.9% were intact, 10.5% were weak, and 8.6% failed. Visual analysis overestimated abnormal bolus clearance compared to EII ratio (p ≤ 0.01). Bolus clearance was complete (median EII ratio 0.0, IQR 0-0.12) in 82.0% of intact swallows in contrast to 53.3% of weak swallows (EII ratio 0.29, IQR 0.0-0.57), and 19.6% of failed swallows (EII ratio 0.5, IQR 0.34-0.73, p

Background Anxiety is a significant modulator of sensitivity along the GI tract. The recently described Esophageal Hypervigilance and Anxiety Score (EHAS) evaluates esophageal-specific anxiety. The aims of this study were as follows: 1. translate and validate an international Spanish version of EHAS. 2. Evaluate its psychometric properties in a large Hispano-American sample of symptomatic individuals. Methods A Spanish EHAS version was developed by a Delphi process and reverse translation. Patients referred for high-resolution manometry (HRM) were recruited prospectively from seven Spanish and Latin American centers. Several scores were used: EHAS, Hospital Anxiety and Depression Scale (HADS), Eckardt score (ES), Gastroesophageal Reflux Questionnaire (GERDQ), and the Brief Esophageal Dysphagia Questionnaire (BEDQ). Standardized psychometric analyses were performed. Key Results A total of 443 patients were recruited. Spanish EHAS showed excellent reliability (Cronbach ' s alpha = 0.94). Factor analysis confirmed the presence of two factors, corresponding to the visceral anxiety and hypervigilance subscales. Sufficient convergent validity was shown by moderate significant correlations between EHAS and other symptomatic scores. Patients with high EHAS scores had significantly more dysphagia. There was no difference in EHAS scores when compared normal vs abnormal or major manometric diagnosis. Conclusions and Inferences A widely usable Spanish EHAS version has been validated. We confirm its excellent psychometric properties in our patients, confirming the appropriateness of its use in different populations. Our findings support the appropriateness of evaluating esophageal anxiety across the whole manometric diagnosis spectrum.

Background Esophagogastric junction contractile integral (EGJ-CI) and EGJ morphology are high-resolution manometry (HRM) metrics that assess EGJ barrier function. Normative data standardized across world regions and HRM manufacturers are limited. Methods Our aim was to determine normative EGJ metrics in a large international cohort of healthy volunteers undergoing HRM (Medtronic, Laborie, and Diversatek software) acquired from 16 countries in four world regions. EGJ-CI was calculated by the same two investigators using a distal contractile integral-like measurement across the EGJ for three respiratory cycles and corrected for respiration (mm Hg cm), using manufacturer-specific software tools. EGJ morphology was designated according to Chicago Classification v3.0. Median EGJ-CI values were calculated across age, genders, HRM systems, and regions. Results Of 484 studies (28.0 years, 56.2% F, 60.7% Medtronic studies, 26.0% Laborie, and 13.2% Diversatek), EGJ morphology was type 1 in 97.1%. Median EGJ-CI was similar between Medtronic (37.0 mm Hg cm, IQR 23.6-53.7 mm Hg cm) and Diversatek (34.9 mm Hg cm, IQR 22.1-56.1 mm Hg cm, P = 0.87), but was significantly higher using Laborie equipment (56.5 mm Hg cm, IQR 35.0-75.3 mm Hg cm, P < 0.001). 5(th) percentile EGJ-CI values ranged from 6.9 to 12.1 mm Hg cm. EGJ-CI values were consistent across world regions, but different between manufacturers even within the same world region (P = 0.3) but higher in women (P < 0.001). Conclusions EGJ morphology is predominantly type 1 in healthy adults. EGJ-CI varies widely in health, with significant gender influence, but is consistent within each HRM system. Manufacturer-specific normative values should be utilized for clinical HRM interpretation.

Chicago Classification v4.0 (CCv4.0) is the updated classification scheme for esophageal motility disorders using metrics from high-resolution manometry (HRM). Fifty-two diverse international experts separated into seven working subgroups utilized formal validated methodologies over two-years to develop CCv4.0. Key updates in CCv.4.0 consist of a more rigorous and expansive HRM protocol that incorporates supine and upright test positions as well as provocative testing, a refined definition of esophagogastric junction (EGJ) outflow obstruction (EGJOO), more stringent diagnostic criteria for ineffective esophageal motility and description of baseline EGJ metrics. Further, the CCv4.0 sought to define motility disorder diagnoses as conclusive and inconclusive based on associated symptoms, and findings on provocative testing as well as supportive testing with barium esophagram with tablet and/or functional lumen imaging probe. These changes attempt to minimize ambiguity in prior iterations of Chicago Classification and provide more standardized and rigorous criteria for patterns of disorders of peristalsis and obstruction at the EGJ. © 2020 John Wiley & Sons Ltd, National Institute of Diabetes and Digestive and Kidney Diseases, NIDDK: P01 DK092217, National Institute of Diabetes and Digestive and Kidney Diseases, Grant/Award Number: P01 DK092217

Background The recently developed Brief Esophageal Dysphagia Questionnaire (BEDQ) evaluates esophageal obstructive symptoms. Its initial evaluation showed strong psychometric properties. The aims of this study were to (a) translate and validate an international Spanish version of BEDQ and (b) evaluate its psychometric properties in a large Hispano-American sample of symptomatic individuals. Methods A Spanish BEDQ version was performed by Hispano-American experts using a Delphi process and reverse translation. Patients were prospectively recruited from seven centers in Spain and Latin America among individuals referred for high-resolution manometry (HRM). Patients completed several scores: Hospital Anxiety & Depression Scale (HADS), Eckardt score (ES), Gastroesophageal Reflux Questionnaire (GERDQ), and the BEDQ. Standardized psychometric analyses were performed. Key Results A total of 426 patients were recruited. Spanish BEDQ showed excellent reliability (Cronbach's alpha = 0.91). Factor analysis confirmed its unidimensional character. Moderate significant correlations between BEDQ and other symptomatic scores were found, suggesting sufficient convergent validity. Patients with abnormal or obstructive HRM findings scored significantly higher when compared to normal or non-obstructive findings, respectively. Using a cutoff of 10, BEDQ showed a sensitivity of 65.38% and a specificity of 66.21% and an area under the curve of 0.71 for obstructive or major manometric diagnosis. Conclusions and Inferences A widely usable Spanish BEDQ version has been validated. We confirm its excellent psychometric properties in our patients, confirming the appropriateness of its use in different populations.

BACKGROUND The definition and relevance of ineffective esophageal motility (IEM) remains debated. Our aim was to determine motility patterns and symptoms associated with IEM defined as impaired bolus clearance. METHODS To define altered bolus clearance, normal range of swallows with complete bolus transit (CBT) on high-resolution impedance manometry (HRIM) was determined in 44 asymptomatic controls. The results were then applied to a cohort of 81 patients with esophageal symptoms to determine the motility patterns which best predicted altered bolus clearance. Subsequently, in a cohort of 281 consecutive patients the identified motility patterns were compared with patients' customary symptoms. KEY RESULTS In asymptomatic controls, the normal range of swallows with CBT was 50%-100%. In patients, altered bolus transit (

Background Eckardt symptom score (ESS) is the most used tool for the evaluation of esophageal symptoms. Recent data suggest that it might have suboptimal reliability and validity. The aims of this study were as follows: (a) Develop and validate an international Spanish ESS version. (b) Perform psychometric ESS evaluation in patients with achalasia and non-achalasia patients. Methods Eckardt symptom score translation was performed by Delphi process. ESS psychometric evaluation was done in two different samples of patients referred for manometry. First sample: 430 dysphagia non-achalasia patients. Second sample: 161 achalasia patients. Internal consistency was evaluated using Cronbach's alpha and Guttman coefficient (0.7 = acceptable). Key Results Our data show that in patients without and with achalasia, ESS behaves similarly. Both show a fair reliability with Cronbach's alpha of 0.57 and 0.65, respectively. Based on our results, we recommend interpretation of the Spanish ESS be done with caution. The psychometric quality of the ESS could not be improved by removal of any items based on the single-factor structure of the scale and no items meeting criteria for elimination. Conclusions and Inferences Eckardt symptom score Spanish translation was developed. ESS showed a fair reliability for the evaluation of patients with any causes of dysphagia. Our results highlight the need for development and psychometric validation of new dysphagia scoring tools.

OBJECTIVES : High-resolution manometry (HRM) is the preferred method for the evaluation of motility disorders. Recently, an update of the diagnostic criteria (Chicago 3.0) has been published. The aim of this study was to compare the performance criteria of Chicago version 2.0 (CC2.0) vs. 3.0 (CC3.0) in a cohort of healthy volunteers and symptomatic patients. METHODS: HRM studies of asymptomatic and symptomatic individuals from several centers of Spain and Latin America were analyzed using both CC2.0 and CC3.0. The final diagnosis was grouped into hierarchical categories: obstruction (achalasia and gastro-esophageal junction obstruction), major disorders (distal esophageal spasm, absent peristalsis, and jackhammer), minor disorders (failed frequent peristalsis, weak peristalsis with small or large defects, ineffective esophageal motility, fragmented peristalsis, rapid contractile with normal latency and hypertensive peristalsis) and normal. The results were compared using McNemar's and Kappa tests. RESULTS: HRM was analyzed in 107 healthy volunteers (53.3% female; 18-69 years) and 400 symptomatic patients (58.5% female; 18-90 years). In healthy volunteers, using CC2.0 and CC3.0, obstructive disorders were diagnosed in 7.5% and 5.6%, respectively, major disorders in 1% and 2.8%, respectively, minor disorders in 25.2% and 15%, respectively, and normal in 66.4% and 76.6%, respectively. In symptomatic individuals, using CC2.0 and CC3.0, obstructive disorders were diagnosed in 11% and 11.3%, respectively, major disorders in 14% and 14%, respectively, minor disorders in 33.3% and 24.5%, respectively, and normal in 41.8% and 50.3%, respectively. In both groups of individuals, only an increase in normal and a decrease in minor findings using CC3.0 were statistically significant using McNemar's test. DISCUSSIONS: CC3.0 increases the number of normal studies when compared with CC2.0, essentially at the expense of fewer minor disorders, with no significant differences in major or obstructive disorders. As the relevance of minor disorders is questionable, our data suggest that CC3.0 increases the relevance of abnormal results.

Background: Multiple water swallow is increasingly used as a complementary challenge test in patients undergoing high-resolution manometry (HRM). Our aim was to establish the range of normal pressure responses during the rapid drink challenge test in a large population of healthy subjects. Methods: Pressure responses to a rapid drink challenge test (100 or 200 mL of water) were prospectively analyzed in 105 healthy subjects studied in nine different hospitals from different countries. Esophageal motility was assessed in all subjects by solid-state HRM. In 18 subjects, bolus transit was analyzed using concomitant intraluminal impedance monitoring. Key Results: A virtually complete inhibition of pressure activity was observed during multiple swallow: Esophageal body pressure was above 20 mm Hg during 1 (0-8) % and above 30 mm Hg during 1 (0-5) % of the swallow period, and the pressure gradient across the esophagogastric junction was low (-1(-7 to 4) mm Hg). At the end of multiple swallow, a postswallow contraction was evidenced in only 50% of subjects, whereas the remaining 50% had non-transmitted contractions. Bolus clearance was completed after 7 (1-30) s after the last swallow, as evidenced by multichannel intraluminal impedance. Conclusions & Inferences: The range of normal pressure responses to a rapid drink challenge test in health has been established in a large multicenter study. Main responses are a virtually complete inhibition of esophageal pressures with a low-pressure gradient across esophagogastric junction. This data would allow the correct differentiation between normal and disease when using this test.

Background: Previous studies have not been able to correlate manometry findings with bolus perception. The aim of this study was to evaluate correlation of different variables, including traditional manometric variables (at diagnostic and extreme thresholds), esophageal shortening, bolus transit, automated impedance manometry (AIM) metrics and mood with bolus passage perception in a large cohort of asymptomatic individuals. Methods: High resolution manometry (HRM) was performed in healthy individuals from nine centers. Perception was evaluated using a 5-point Likert scale. Anxiety was evaluated using Hospitalized Anxiety and Depression scale (HAD). Subgroup analysis was also performed classifying studies into normal, hypotensive, vigorous, and obstructive patterns. Key Results: One hundred fifteen studies were analyzed (69 using HRM and 46 using high resolution impedance manometry (HRIM); 3.5% swallows in 9.6% of volunteers were perceived. There was no correlation of any of the traditional HRM variables, esophageal shortening, AIM metrics nor bolus transit with perception scores. There was no HRM variable showing difference in perception when comparing normal vs extreme values (percentile 1 or 99). Anxiety but not depression was correlated with perception. Among hypotensive pattern, anxiety was a strong predictor of variance in perception (R-2 up to .70). Conclusion and Inferences: Bolus perception is less common than abnormal motility among healthy individuals. Neither esophageal motor function nor bolus dynamics evaluated with several techniques seems to explain differences in bolus perception. Different mechanisms seem to be relevant in different manometric patterns. Anxiety is a significant predictor of bolus perception in the context of hypotensive motility.

This is the peer reviewed version of the following article: Bendezú, R. A., Barba, E., Burri, E., Cisternas, D., Accarino, A., Quiroga, S., Monclus, E., Navazo, I., Malagelada, J.-R. and Azpiroz, F. (2016), Colonic content in health and its relation to functional gut symptoms. Neurogastroenterol. Motil., 28: 849–854, which has been published in final form at [doi:10.1111/nmo.12782]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving Gut content may be determinant in the generation of digestive symptoms, particularly in patients with impaired gut function and hypersensitivity. Since the relation of intraluminal gas to symptoms is only partial, we hypothesized that non-gaseous component may play a decisive role. Methods: Abdominal computed tomography scans were evaluated in healthy subjects during fasting and after a meal (n = 15) and in patients with functional gut disorders during basal conditions (when they were feeling well) and during an episode of abdominal distension (n = 15). Colonic content and distribution were measured by an original analysis program. Key results: In healthy subjects both gaseous (87 ± 24 mL) and non-gaseous colonic content (714 ± 34 mL) were uniformly distributed along the colon. In the early postprandial period gas volume increased (by 46 ± 23 mL), but non-gaseous content did not, although a partial caudad displacement from the descending to the pelvic colon was observed. No differences in colonic content were detected between patients and healthy subjects. Symptoms were associated with discrete increments in gas volume. However, no consistent differences in non-gaseous content were detected in patients between asymptomatic periods and during episodes of abdominal distension. Conclusions & inferences: In patients with functional gut disorders, abdominal distension is not related to changes in non-gaseous colonic content. Hence, other factors, such as intestinal hypersensitivity and poor tolerance of small increases in luminal gas may be involved.

The abdomen normally accommodates intra-abdominal volume increments. Patients complaining of abdominal distension exhibit abnormal accommodation of colonic gas loads (defective contraction and excessive protrusion of the anterior wall). However, abdominal imaging demonstrated diaphragmatic descent during spontaneous episodes of bloating in patients with functional gut disorders. We aimed to establish the role of the diaphragm in abdominal distension.In 20 patients complaining of abdominal bloating and 15 healthy subjects, we increased the volume of the abdominal cavity with a colonic gas load, while measuring abdominal girth and electromyographic activity of the anterior abdominal muscles and of the diaphragm.In healthy subjects, the colonic gas load increased girth, relaxed the diaphragm, and increased anterior wall tone. With the same gas load, patients developed significantly more abdominal distension; this was associated with paradoxical contraction of the diaphragm and relaxation of the internal oblique muscle.In this experimental provocation model, abnormal accommodation of the diaphragm is involved in abdominal distension.

BACKGROUND & AIMS: In patients with functional gut disorders, abdominal distension has been associated with descent of the diaphragm and protrusion of the anterior abdominal wall. We investigated mechanisms of abdominal distension in these patients. METHODS: We performed a prospective study of 45 patients (42 women, 24-71 years old) with functional intestinal disorders (27 with irritable bowel syndrome with constipation, 15 with functional bloating, and 3 with irritable bowel syndrome with alternating bowel habits) and discrete episodes of visible abdominal distension. Subjects were assessed by abdominothoracic computed tomography (n = 39) and electromyography (EMG) of the abdominothoracic wall (n = 32) during basal conditions (without abdominal distension) and during episodes of severe abdominal distension. Fifteen patients received a median of 2 sessions (range, 1-3 sessions) of EMG-guided, respiratory-targeted biofeedback treatment; 11 received 1 control session before treatment. RESULTS: Episodes of abdominal distension were associated with diaphragm contraction (19% +/- 3% increase in EMG score and 12 +/- 2 mm descent; P < .001 vs basal values) and intercostal contraction (14% +/- 3% increase in EMG scores and 6 +/- 1 mm increase in thoracic antero-posterior diameter; P < .001 vs basal values). They were also associated with increases in lung volume (501 +/- 93 mL; P < .001 vs basal value) and anterior abdominal wall protrusion (32 +/- 3 mm increase in girth; P < .001 vs basal). Biofeedback treatment, but not control sessions, reduced the activity of the intercostal muscles (by 19% +/- 2%) and the diaphragm (by 18% +/- 4%), activated the internal oblique muscles (by 52% +/- 13%), and reduced girth (by 25 +/- 3 mm) (P

Patients with irritable bowel syndrome and abdominal bloating exhibit abnormal responses of the abdominal wall to colonic gas loads. We hypothesised that in patients with postprandial bloating, ingestion of a meal triggers comparable abdominal wall dyssynergia. Our aim was to characterise abdominal accommodation to a meal in patients with postprandial bloating.A test meal (0.8 kcal/ml nutrients plus 27 g/litre polyethylenglycol 4000) was administered at 50 ml/min as long as tolerated in 10 patients with postprandial bloating (fulfilling Rome III criteria for postprandial distress syndrome) and 12 healthy subjects, while electromyographic (EMG) responses of the anterior wall (upper and lower rectus, external and internal oblique via bipolar surface electrodes) and the diaphragm (via six ring electrodes over an oesophageal tube in the hiatus) were measured. Means +/- SD were calculated.Healthy subjects tolerated a meal volume of 913±308 ml; normal abdominal wall accommodation to the meal consisted of diaphragmatic relaxation (EMG activity decreased by 15±6%) and a compensatory contraction (25±9% increase) of the upper abdominal wall muscles (upper rectus and external oblique), with no changes in the lower anterior muscles (lower rectus and internal oblique). Patients tolerated lower volume loads (604±310 ml; p=0.030 vs healthy subjects) and developed a paradoxical response, that is, diaphragmatic contraction (14±3% EMG increment; p0.01 vs healthy subjects) and upper anterior wall relaxation (9±4% inhibition; p0.01 vs healthy subjects).In functional dyspepsia, postprandial abdominal distension is produced by an abnormal viscerosomatic response to meal ingestion that alters normal abdominal accommodation.

Contraction Amplitude Is a Relevant Predictor of Bolus Transit During Sitting Viscous Solution Swallows in Healthy Individuals: Preliminary Results of a Multicenter Study Using High Resolution Impedance Manometry (HRIM) Daniel Cisternas, Roberto A. Candia, Ingrid Marin, Jordi Serra, Antonio Ruiz de Leon, Julio Perez de la Serna, Concepcion Sevilla, Albis C. Hani, Alberto Rodriguez, Ana Maria Leguizamo, Miguel A. Valdovinos, Arturo Meixueiro, Miguel Angel Zavala, Jose Maria Remes-Troche, Ramiro Coello Jaramillo, Eponina Maria de Oliveira Lemme, Luiz Abrahao Junior, Andres Ditaranto, Claudio R. Bilder