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R O Dantas

Publications and source records attributed to R O Dantas.

At least 19 recordsLinked to original sources
PubMed2006

Differences in response of the proximal esophagus to wet swallows in patients of Chagas' disease and idiopathic achalasia.

Chagas' disease and idiopathic achalasia have similar esophageal manifestations such as absent or incomplete lower esophageal sphincter relaxation and aperistalsis in the esophageal body (alterations seen mainly in the distal esophageal body). Our aim in this paper was to study the response of the proximal esophageal body to wet swallows in patients with Chagas' disease and patients with idiopathic achalasia. We retrospectively analyzed the time interval between the onset of the pharyngeal contractions 1 cm proximal to the upper esophageal sphincter, as well as 5 cm distal to the pharyngeal measurement. Amplitude, duration and area under the curve of contractions in the proximal esophagus were also determined in 42 patients with Chagas' disease (15 with associated esophageal dilatation), 21 patients with idiopathic achalasia (14 with concomitant esophageal dilatation) and 31 control subjects. The time between the onset of pharyngeal and proximal esophageal contractions was longer in patients with Chagas' disease and in those with esophageal dilatation (1.39 +/- 0.16 s) than in control subjects (0.86 +/- 0.04 s, P < 0.01). The amplitude of proximal esophageal contractions was lower in patients with idiopathic achalasia and esophageal dilatation (60.9 +/- 16.3 mmHg) than in control subjects (89.7 +/- 6.9 mmHg, P = 0.06). The authors conclude that in patients with advanced esophageal disease, the proximal esophageal contractions in Chagas' disease have a delayed response to wet swallows when compared with controls, and that the amplitude of proximal esophageal contractions was lower than expected in patients with idiopathic achalasia.

Adult↗
PubMed2006

Primary and secondary esophageal contractions in patients with gastroesophageal reflux disease.

We studied the primary and secondary esophageal peristalsis in 36 patients with heartburn and acid regurgitation and in 14 asymptomatic volunteers. Primary peristalsis was elicited by ten swallows of a 5-mL bolus of water and secondary peristalsis was elicited by intra-esophageal infusion of 5, 10, and 15 mL water, 0.1 N hydrochloric acid and air. Esophageal contractions were measured by an 8-lumen manometric catheter assembly incorporating a 6-cm sleeve device. Contractions were registered at 3, 9, and 15 cm from the upper margin of the sleeve and the infusion was done through a side hole located at 12 cm. Twenty patients had normal endoscopic esophageal examination, 10 with normal (group I) and 10 with abnormal pH-metric examination (group II), and 16 had esophagitis (group III). The amplitude of contractions after swallows was lower (97.8 +/- 10.0 mmHg) in the distal esophagus of group III patients than in controls (142.3 +/- 14.0 mmHg). Patients of group III had fewer secondary contractions (water: 25% of infusion) than patients of the other groups and controls (67% of infusion). Patients of group III also had a lower amplitude of secondary peristalsis in the distal esophagus (water: 70.1 +/- 9.6 mmHg) than controls (129.2 +/- 18.2 mmHg). We conclude that patients with esophagitis have an impairment of primary and secondary peristalsis in the distal esophagus.

Adolescent↗
PubMed2005

Effect of treatment of dentofacial deformities on the electromyographic activity of masticatory muscles.

Individuals with dentofacial deformities present changes in masticatory muscles. The objective of the present study was to determine the influence of interdisciplinary treatment in cases of class III dentofacial deformities regarding the EMG activity of the temporal (T) and masseter (M) muscles. The study was conducted on 15 patients with class III dentofacial deformities who were submitted to orthodontic, oromyofunctional and surgical treatment and assigned to groups P1 (before surgery) and P2 (6-9 months after surgery). Fifteen individuals with no alterations in facial morphology or dental occlusion and without signs or symptoms of temporomandibular joint dysfunction were used as controls (CG). The T and M muscles were submitted to EMG bilaterally in the situations of mastication and mastication plus biting, with analysis of amplitude interval and root mean square. For all muscles tested, there was a difference between CG, P1 and P2; CG was higher than P2 and P2 higher than P1 in all situations assessed. We conclude that there was an increase in EMG activity in the T and M muscles after surgical correction of the dentofacial deformity accompanied by interdisciplinary treatment, although the values were still lower than those obtained for CG.

Adult↗
PubMed2005

Residence of liquids in the infra-junctional portion of the proximal stomach in patients with gastroesophageal reflux disease.

Patients with gastroesophageal reflux disease may have disturbances of gastric motility, which could play a role in the pathophysiology of the disease. Recent studies have suggested that the gastric region just below the gastroesophageal junction may have a distinct physiological behavior. We determined whether patients with gastroesophageal reflux disease have abnormal residence of food in the infra-junctional portion of the stomach after ingesting a liquid nutrient meal. Fasted adult patients with reflux disease (N = 11) and healthy volunteers (N = 10) ingested a liquid meal (320 ml; 437 kcal) labeled with 99m technetium-phytate and their total gastric emptying half-time and regional emptying from the stomach infra-junctional region were determined. In 8 patients, episodes of postprandial acidic reflux to the esophagus were measured for 2 h using pH monitoring. There were no differences between reflux patients and controls regarding total gastric emptying time (median: 68 min; range: 39-123 min vs 65 min and 60-99 min, respectively; P > 0.50). Food residence in the infra-junctional area was similar for patients and controls: 23% (range: 20-30) vs 27% (range: 19-30%; P = 0.28) and emptying from this area paralleled total gastric emptying (Rs = 0.79; P = 0.04). There was no correlation between residence of food in the infra-junctional area and episodes of gastroesophageal reflux (Rs = 0.06; P = 0.88). We conclude that it is unlikely that regional motor disturbances involving the infra-junctional region of the stomach play a relevant role in the pathogenesis of acidic gastroesophageal reflux.

Adult↗
PubMed2003

Effect of successive swallows on oesophageal motility of normal volunteers, patients with Chagas' disease and patients with idiopathic achalasia.

Most frequently, ten swallows of a 5-mL bolus of water are performed during oesophageal manometry. Our hypothesis is that five swallows may produce the same results. We studied the oesophageal contraction parameters of 40 volunteers, 75 patients with Chagas' disease and 14 patients with idiopathic achalasia. Motility was recorded at 5, 10 and 15 cm above the lower oesophageal sphincter. The subjects performed ten swallows of a 5-mL bolus of water alternated with ten dry swallows with an interval of at least 30 s. We measured the amplitude, duration, peristaltic velocity, number of failed and number of simultaneous contractions of the initial five and final five dry and wet swallows. The comparison of dry and wet swallows showed the differences already known. The comparison of the parameters of the initial five swallows with those of the final five swallows showed no differences. Thus, when the initial five or the final five swallows were considered, there was no change in the conclusions reached by the comparison of patients and volunteers and of dry and wet swallows. We conclude that five swallows may be sufficient for the manometric examination of oesophageal parameters in Chagas' disease and idiopathic achalasia.

Adult↗
PubMed2002

Vigorous achalasia in Chagas' disease.

The study investigated the esophageal motility of 98 patients with Chagas' disease and 40 asymptomatic volunteers, with the objective of comparing patients with vigorous achalasia (distal amplitude contractions >/= 37 mmHg) and patients with classical achalasia (amplitude < 37 mmHg). The Chagas' disease patients had normal esophageal radiologic transit (n=60) or esophageal slow transit and retention without dilation (n=38). The manometric method with continuous perfusion was used to study esophageal motility. Comparison of classical and vigorous achalasia showed no difference in duration of contractions, lower and upper esophageal sphincter pressure, proportion of patients with dysphagia, or the number of multipeaked contractions. The number of failed contractions was higher in patients with classic achalasia than in patients with vigorous achalasia. We conclude that the distinction between classical and vigorous achalasia does not seem to be important for the classification of Chagas' disease.

Adult↗
PubMed2002

Esophageal striated muscle contractions in patients with Chagas' disease and idiopathic achalasia.

Chagas' disease causes degeneration and reduction of the number of intrinsic neurons of the esophageal myenteric plexus, with consequent absent or partial lower esophageal sphincter relaxation and loss of peristalsis in the esophageal body. The impairment of esophageal motility is seen mainly in the distal smooth muscle region. There is no study about esophageal striated muscle contractions in the disease. In 81 patients with heartburn (44 with esophagitis) taken as controls, 51 patients with Chagas' disease (21 with esophageal dilatation) and 18 patients with idiopathic achalasia (11 with esophageal dilatation) we studied the amplitude, duration and area under the curve of esophageal proximal contractions. Using the manometric method and a continuous perfusion system we measured the esophageal striated muscle contractions 2 to 3 cm below the upper esophageal sphincter after swallows of a 5-ml bolus of water. There was no significant difference in striated muscle contractions between patients with heartburn and esophagitis and patients with heartburn without esophagitis. There was also no significant difference between patients with heartburn younger or older than 50 years or between men and women or in esophageal striated muscle contractions between patients with heartburn and Chagas' disease. The esophageal proximal amplitude of contractions was lower in patients with idiopathic achalasia than in patients with heartburn. In patients with Chagas' disease there was no significant difference between patients with esophageal dilatation and patients with normal esophageal diameter. Esophageal striated muscle contractions in patients with Chagas' disease have the same amplitude and duration as seen in patients with heartburn. Patients with idiopathic achalasia have a lower amplitude of contraction than patients with heartburn.

Adolescent↗
PubMed2001

Pharyngeal clearance and pharyngeal transit time determined by a biomagnetic method in normal humans.

Clearance and transit time are parameters of great value in studies of digestive transit. Such parameters are nowadays obtained by means of scintigraphy and videofluoroscopy, with each technique having advantages and disadvantages. In this study we present a new, noninvasive method to study swallowing pharyngeal clearance (PC) and pharyngeal transit time (PTT). This new method is based on variations of magnetic flux produced by a magnetic bolus passing through the pharynx and detected by an AC biosusceptometer (ACB). These measurements may be performed in a simple way, cause no discomfort, and do not use radiation. We measured PC in 8 volunteers (7 males and 1 female, 23-33 years old) and PTT in 8 other volunteers (7 males and 1 female, 21-29 years old). PC was 0.82 +/- 0.10 s (mean +/- SD) and PTT was 0.75 +/- 0.03 s. The results were similar for PC but longer for PTT than those determined by means of other techniques. We conclude that the biomagnetic method can be used to evaluate PC and PTT.

Adult↗
PubMed2001

Esophageal motility of patients with Chagas' disease and idiopathic achalasia.

Chagas' disease and idiopathic achalasia have the same neuropathic lesion--the loss of ganglion cells within the esophageal myenteric plexus--with similar clinical, radiologic, and manometric features. However, it is suggested that there are some differences between them. We studied the esophageal motility of 45 patients with Chagas' disease (seven with esophageal dilation), 27 patients with idiopathic achalasia (13 with esophageal dilation), and 40 asymptomatic volunteers. We used the manometric method with continuous perfusion. The lower esophageal sphincter (LES) pressure was measured by the rapid pull-through method. Esophageal contractions was evaluated at 5, 10, and 15 cm above the LES, after 10 swallows of a 5-ml bolus of water alternated with 10 dry swallows. LES pressure was higher in achalasia than in Chagas' disease patients and controls (P < 0.05). Amplitude of contraction was lower in all patient groups compared with controls (P < 0.01) and lower in patients with dilation compared with patients without dilation (P < 0.05). The contraction duration was longer in patients with achalasia than in patients with Chagas' disease and controls (P < 0.05). The percentage of failed contractions was higher in Chagas' disease than in achalasia and controls (P < 0.05), and the percentage of simultaneous contractions was higher in patients with idiopathic achalasia than in patients with Chagas' disease and controls (P < 0.05). The results suggest the possibility that the extent of impairment of esophageal innervation differs between Chagas' disease and idiopathic achalasia.

Adult↗
PubMed2000

A scintigraphic study of oropharyngeal swallowing dynamics in Chagas' disease.

We studied oropharyngeal function in patients with Chagas' disease and oesophageal disease. Twenty-four patients with Chagas' disease, 17 of them with oesophageal disease, were submitted to scintigraphic oropharyngeal transit. A single swallow of a 10-mL bolus of water labelled with 40 MBq 99m Tc-phytate, followed by image acquisition at 20 images s-1 yielded time-activity curves in which oropharyngeal dynamics was evaluated. Thirteen normal volunteers were used as controls. Oral transit was longer for chagasics with oesophageal disease than for controls (P=0.004) or for chagasics with a normal oesophagus (P=0.028). Oesophageal filling rate, measured by the slope of the ascending aspect of the oesophageal radioactivity curve, was lower for chagasics with oesophageal disease than for controls (P=0.037). Also, maximum oesophageal filling rate was lower (P=0. 021) and occurred later (P=0.003) for chagasics with oesophageal disease than for controls. Pharyngeal clearance was positively correlated with oral transit (r=0.603, P=0.002). We conclude that chagasic oesophageal disease is associated with oral transit delay and a slower oesophageal filling rate.

Adult↗
PubMed2000

Effect of gastroesophageal reflux on hypertrophy of the base of the tongue.

The objective of this study was to determine a possible association between pharyngolaryngeal signs of gastroesophageal reflux (GER) and hypertrophy of the lymphoid follicles at the base of the tongue (HBT). For this purpose, 306 patients submitted to videolaryngoscopy were studied retrospectively and classified according to the presence and size of follicles on the base of the tongue. HBT was considered to be present when the follicles prevented the view of the vallecula. The patients were grouped according to the presence of videolaryngoscopic signs of GER and further subdivided according to the presence of esophageal, pharyngolaryngeal, and esophagopharyngolaryngeal symptoms, with an attempt made to relate these symptoms to the presence of HBT. HBT was detected in 62.4% (63/101) of the patients with signs of GER and in 29.3% (60/205) of patients with no signs of GER. When HBT incidence was studied according to the symptoms reported by the patient, the condition was found to be present in 57.2% (8/14) of patients with exclusively esophageal symptoms, in 63.6% (21/33) with esophagopharyngolaryngeal symptoms, and in 75% (15/20) with exclusively pharyngolaryngeal symptoms. We conclude therefore that HBT is associated with GER.

Gastroesophageal Reflux↗
PubMed2000

Upper esophageal sphincter pressure in patients with Chagas' disease and primary achalasia.

The most important component of the upper esophageal sphincter (UES) is the cricopharyngeal muscle. During the measurement of sphincter pressure the catheter passed through the sphincter affects the pressure value. In Chagas' disease and primary achalasia there is an esophageal myenteric plexus denervation which may affect UES pressure. We measured the UES pressure of 115 patients with Chagas' disease, 28 patients with primary achalasia and 40 healthy volunteers. We used a round manometric catheter with continuous perfusion and the rapid pull-through method, performed in triplicate during apnea. Pressures were measured in four directions, and the direction with the highest pressure (anterior/posterior) and the average of the four directions were measured. The highest UES pressure in Chagas' disease patients without abnormalities upon radiologic esophageal examination (N = 63) was higher than in normal volunteers (142.8 +/- 47.4 mmHg vs 113.0 +/- 46.0 mmHg, mean +/- SD, P<0.05). There was no difference in UES pressure between patients with primary achalasia and patients with Chagas' disease and similar esophageal involvement and normal volunteers (P>0.05). There was no difference between patients with or without esophageal dilation. In the group of subjects less than 50 years of age the UES pressure of primary achalasia (N = 21) was lower than that of Chagas' disease patients with normal radiologic esophageal examination (N = 41), measured at the site with the highest pressure (109.3 +/- 31.5 mmHg vs 149.6 +/- 45.3 mmHg, P<0.01) and as the average of the four directions (64.2 +/- 17.1 mmHg vs 83.5 +/- 28.6 mmHg, P<0.05). We conclude that there is no difference in UES pressure between patients with Chagas' disease, primary achalasia and normal volunteers, except for patients with minor involvement by Chagas' disease, for whom the UES pressure at the site with the highest pressure was higher than the pressure of normal volunteers and patients with primary achalasia.

Adult↗
PubMed1999

Esophageal manometric and radiologic findings in asymptomatic subjects with Chagas' disease.

We studied 68 asymptomatic subjects (63 men) aged 19-67 years (median age, 41.5 years), who were candidates to donate blood at the University Hospital of the School of Medicine of Ribeirão Preto whose serologic examination result for Chagas' disease was positive. These individuals underwent a resting electrocardiogram (ECG). chest and esophageal radiographic examinations, and esophageal manometry. Thirty-three subjects (49%) had normal esophageal and cardiac examinations. Twenty-eight (41%) had an abnormal ECG and/or abnormal chest radiograph, 18 of them with normal findings on both esophageal manometry and radiograph. Two of the other 10 subjects had normal results on manometry and an abnormal esophageal radiograph. Eight of these subjects had manometric abnormalities which included decreased contraction amplitude (n = 4), failed lower esophageal sphincter (LES) relaxation (n = 1), and simultaneous contractions (n = 3). Esophageal radiographic examination showed no alteration in five cases and esophageal retention in three. Only seven subjects (10%) exhibited exclusive esophageal manifestations, that is, simultaneous contractions (n = 5), simultaneous contractions with failed LES relaxation (n = 1), and esophageal retention (n = 1). Of the total group of 68 subjects, 17 (25%) had some esophageal abnormality observed on manometry (14 cases [21%]) and on radiographic examination (6 cases [9%]). We conclude that asymptomatic subjects with Chagas' disease may have cardiac and esophageal alterations which may be detectable by the examinations regularly used to study heart and esophagus.

Adult↗
PubMed1998

Dysphagia in patients with Chagas' disease.

Some patients with Chagas' disease and apparent normal esophageal function complain of dysphagia. With the objective of investigating the esophageal motility of these patients we studied the esophageal contraction amplitude, duration, velocity, and lower esophageal sphincter (LES) pressure of 34 patients with a positive serologic test for Chagas' disease, normal radiologic esophageal examination, peristaltic contractions in the esophageal body, and complete LES relaxation. Fourteen patients complained of dysphagia and 20 had no symptoms. The results were compared with those of 22 healthy controls. We used the manometric method with continuous perfusion. In patients without dysphagia, the LES pressure (17.8 +/- 1.2 mmHg, mean +/- SEM) and distal esophageal amplitude (71.8 +/- 7.9 mmHg) were lower than those of control subjects (24.3 +/- 1.8 mmHg and 100. 4 +/- 10.6 mmHg, respectively). The velocity of peristaltic contractions was higher in patients than in controls, but there was no difference between patients with or without dysphagia. The duration of contraction in the distal esophagus was longer in patients with dysphagia (3.9 +/- 0.2 sec) than in patients without dysphagia (3.1 +/- 0.2 sec) and controls (3.2 +/- 0.2 sec). We conclude that dysphagia in patients with Chagas' disease and a nondilated esophagus with peristaltic contractions and complete LES relaxation is related to a longer duration of contractions in the middle and distal esophageal body.

Adult↗
PubMed1998

HLA class I and II profiles of patients presenting with Chagas' disease.

To evaluate the HLA class I and II profiles of a large group of patients with Chagas' disease, 176 patients presenting with pure cardiomyopathy with heart failure (N = 60), cardiomyopathy without heart failure (N = 18), pure digestive tract manifestations (N = 25), cardiac plus digestive disease (N = 40), and asymptomatic patients with positive serology for chronic Trypanosoma cruzi infection (N = 33) were studied. A total of 448 normal individuals were also studied in parallel. HLA class I and II specificities were determined using serology and oligonucleotide analysis. HLA-A30 antigen was overrepresented in the total group and in the subgroups presenting with the pure cardiac (with or without heart failure) or digestive form, conferring similar relative risks and etiologic fractions on all these presentation forms. Serologic HLA class II analysis showed that HLA-DQ1 conferred susceptibility to, while HLA-DQ7 antigen conferred protection against the development of the disease in the total group of patients. Oligonucleotide typing did not confirm the HLA class II associations obtained by serology, but showed that HLA-DQB1*06 alleles were underrepresented in the total group and in the subgroups presenting with pure digestive or cardiac disease, conferring closely similar relative risks and preventive fractions. Although asymptomatic patients showed a tendency to increased HLA-A30, they presented a significant increase of HLA-DQB1*0302 specificity. In conclusion, HLA-A30 antigen conferred susceptibility to, while HLA-DQB1*06 specificity conferred protection against, the development of the disease, regardless of the form of presentation, ie, cardiac or digestive tract disease.

Adult↗
PubMed1998

Intraesophageal balloon distension test in Chagas' disease patients with noncardiac chest pain.

Patients with Chagas' disease often have chest pain as a prominent symptom. The objective of this study was to compare the results of intraesophageal balloon distension in chagasic and nonchagasic patients with chest pain not caused by coronary obstruction. We studied 40 patients with chest pain and angiographically normal coronary arteries, 25 with a positive serologic test for Chagas' disease (Chagas group, 16 women, mean age 53+/-10 years), and 15 with a negative serologic test (control group, 11 women, mean age 46+/-10 years). All patients had radiologic and endoscopic examinations of esophagus, stomach, and duodenum, esophageal manometry with the acid infusion test in the distal esophagus, and intraesophageal balloon distension. None of them had esophageal dilation or any signs of cardiovascular disease. A 25-mm-long latex balloon located 10 cm above the lower esophageal sphincter was inflated and deflated over a period of 10 sec at 1-ml increments of air until the subjects reported chest pain or to a maximum volume of 20 mi. The test caused chest pain in 14 subjects in the control group (93%) and in 12 in the Chagas' disease group (48%, P < 0.05). The mean volume of air that caused chest pain was 10+/-3 ml in the control group and 15+/-4 ml in the Chagas' disease group (mean+/-SD, P < 0.05). The maximum intraesophageal pressure during the examination was higher in Chagas' disease patients with chest pain during balloon distension (60 +/- 21 mm Hg) than in patients who did not have chest pain (37 +/-18 mm Hg, P < 0.05) and did not differ from the control group (48+/-16 mm Hg, P > 0.05). With the other examinations there was no difference between groups or between patients with or without chest pain during the balloon distension test. Although esophagitis was observed in 47% of patients in the control group and in 40% of the Chagas' disease group, the acid infusion test was positive in 27% of patients in the control group and in 4% of patients in the Chagas' disease group. We conclude that, as compared to a group of patients with similar chest pain, chagasic patients are less sensitive to esophageal distension. Thus, it is unlikely that their chest pain is related to esophageal mechanisms.

Adult↗
PubMed1998

Cricopharyngeal dysfunction in a patient with achalasia.

A 64-year-old man had intense dysphagia and aspiration of 1 month's duration. The patient had lower esophageal sphincter (LES) achalasia and cricopharyngeal dysfunction, with generalized muscle weakness discovered by neurologic examination. Endoscopy showed no lesions of the mouth, pharynx, larynx, or esophagus. The diagnosis of achalasia was made by manometry. The LES did not relax with deglutition; the contractions in the esophageal body were nonperistaltic and of low amplitude; and the upper esophageal sphincter pressure did not decrease after deglutition. A scintigraphic study of the oral and pharyngeal phases of swallowing showed a mouth and pharyngeal retention of 90% of the volume swallowed.

Deglutition Disorders↗