The molecular pathology of urological malignancies

BACKGROUND: Effective esophageal peristalsis is a major determinant of esophageal clearance function. The relation of esophageal body function with a mechanically defective lower esophageal sphincter and the development of esophageal mucosal injury in patients with gastroesophageal reflux disease is unclear. STUDY DESIGN: We analyzed the relations among the manometrically determined esophageal clearance function, lower esophageal sphincter dysfunction, esophageal acid exposure, and the presence and severity of esophageal mucosal injury in patients with gastroesophageal reflux disease. Normal values for the manometric assessment of esophageal clearance function were established in 50 normal volunteers and subsequently applied to 160 symptomatic patients with increased esophageal exposure to gastric juice and various grades of esophageal mucosal injury (no minimal surgery, esophagitis, stricture, and Barrett's esophagus). RESULTS: Defective clearance function was present in 47.5% of the patients; a defective lower esophageal sphincter was documented in 63.1%. Compromised esophageal clearance function was significantly more common in patients with a defective lower esophageal sphincter than in those with normal sphincter function (55% versus 33.8%). Esophageal acid exposure time and the prevalence and severity of esophageal mucosal injury were highest in patients with a defective sphincter and compromised clearance function. CONCLUSIONS: These data show that esophageal motor function deteriorates with increasing severity of mucosal injury. This appears to be due to persistent reflux of gastric juice across a mechanically defective lower esophageal sphincter. This may influence the choice and outcome of antireflux surgery. Surgical correction of a mechanically defective sphincter before the loss of esophageal body function is advocated.     

Design and synthesis of small semi-mimetic peptides with immunomodulatory activity based on myelin basic protein (MBP)

Bile reflux has been implicated in the pathogenesis and malignant degeneration of Barrett's esophagus, but clinical studies in patients with adenocarcinoma arising in Barrett's esophagus are lacking. Ambulatory esophageal measurement of acid and bile reflux was performed with the previously validated fiberoptic bilirubin monitoring system (Bilitec) combined with a pH probe in 20 asymptomatic volunteers, 19 patients with gastroesophageal reflux disease (GERD) but no mucosal injury, 45 patients with GERD and erosive esophagitis, 33 patients with GERD and Barrett's esophagus, and 14 patients with early adenocarcinoma arising in Barrett's esophagus. Repeat studies were done in 15 patients under medical acid suppression and 16 patients after laparoscopic Nissen fundoplication. The mean esophageal bile exposure time showed an exponential increase from GERD patients without esophagitis to those with erosive esophagitis and benign Barrett's esophagus and was highest in patients with early carcinoma in Barrett's esophagus (P <0.01). Pathologic esophageal bile exposure was documented in 18 (54.5%) of 33 patients with benign Barrett's esophagus and 11 (78.6%) of 14 patients with early adenocarcinoma in Barrett's esophagus. Nissen fundoplication but not medical acid suppression resulted in complete suppression of bile reflux. Bile reflux into the esophagus is particularly prevalent in patients with Barrett's esophagus and early cancer. Bile reflux into the esophagus can be completely suppressed by Nissen fundoplication but not medical acid suppression alone.     

Is Barrett's esophagus characterized by more pronounced acid reflux than severe esophagitis?

OBJECTIVE: Barrett's esophagus is related to gastroesophageal reflux disease (GERD). However, only a small fraction of patients with GERD develop Barrett's esophagus. We evaluated whether gastroesophageal acid reflux is more pronounced in Barrett's patients than in patients with moderate or severe endoscopic esophagitis. METHODS: Retrospective evaluation of results of esophageal manometry and 24 hour ambulatory pH monitoring performed between 1990 and 1996 at the Leiden University Medical Center in those patients who also underwent endoscopy < or = 3 months before pH-metry. Included were 51 patients with Barrett's esophagus, 30 patients with severe esophagitis, 45 patients with moderate esophagitis, and 24 healthy control subjects. RESULTS: Patients with Barrett's esophagus had significantly increased acid reflux time (p < 0.01-0.05) compared to patients with moderate, but not compared to patients with severe esophagitis. Distal esophageal body motility and LES pressure were significantly (p < 0.01-0.05) reduced in patients with Barrett's esophagus compared to patients with moderate esophagitis but not compared to those with severe esophagitis. CONCLUSION: Although acid reflux is increased in patients with Barrett's esophagus and esophageal motility is impaired, other factors apart from acid exposure and motility contribute to the development of Barrett's esophagus.     

Gastro-oesophageal reflux associated with nocturnal gastric acid breakthrough on proton pump inhibitors

BACKGROUND: Nocturnal gastric acid breakthrough, defined as intragastric pH < 4 for more than 1 h in the overnight period, is observed in up to 70% of normal subjects on proton pump inhibitors taken twice daily. The frequency of this breakthrough in patients with gastro-oesophageal reflux and accompanying oesophageal reflux during this period has not been studied. AIM: To examine the frequency of nocturnal break-through and accompanying oesophageal acid exposure in patients with gastro-oesophageal reflux treated with proton pump inhibitors twice daily. METHODS: Prolonged ambulatory pH records from 76 patients on twice daily proton pump inhibitors between January 1991 and July 1997 were analysed for the presence of nocturnal gastric acid breakthrough and accompanying oesophageal pH < 4. Studies from 31 normal subjects on twice daily proton pump inhibitors constituted the control group. RESULTS: Nocturnal gastric acid breakthrough was seen in 70% of 61 patients with gastro-oesophageal reflux, 80% of 15 patients with Barrett's oesophagus and 67% of normal controls (P=N.S.). Oesophageal acid exposure was seen in 33% of gastro-oesophageal reflux patients, 50% of Barrett's oesophagus patients and 8% of normal controls (P < 0.03). No difference was found between patients taking omeprazole or lansoprazole. CONCLUSION: Nocturnal acid breakthrough is frequently seen on proton pump inhibitors twice daily and is often accompanied by oesophageal reflux. This has important implications for medical therapy in patients with severe gastro-oesophageal reflux and Barrett's oesophagus.     

pH-metric analysis after successful antireflux surgery: comparison of 24-hour pH profiles in patients undergoing floppy fundoplication or Roux-en-Y duodenal diversion

Fundoplication is the most widely used antireflux method, whereas Roux-en-Y duodenal diversion (partial gastrectomy, vagotomy, and Roux-en-Y reconstruction) has been used in fewer patients with more complicated gastroesophageal reflux disease. Abnormal esophageal pH values are normalized after successful fundoplication. However, very little is known about possible changes in the pH profile after successful Roux-en-Y duodenal diversion. A total of 37 patients with severe gastroesophageal reflux disease were treated by fundoplication (n=22) or Roux-en-Y duodenal diversion (n=15). Postoperatively all patients in both groups were symptom free and healing of esophagitis was verified endoscopically. After fundoplication, the 24-hour esophageal acid exposure decreased significantly (P=0.03) and the pH profile normalized (pH<4 in 5.8%+/-2.4% of the recorded time). However, the decrease in esophageal acid exposure was not significant (P=0.77) after successful Roux-en-Y reconstruction and the pH profile remained abnormal (pH<4 in 15.1%+/-4.3%). It was concluded that 24-hour esophageal pH monitoring is a reliable means of assessing the results of fundoplication, but the current test criteria should be reexamined in evaluating the results of Roux-en-Y duodenal diversion. Healing of esophagitis after Roux-en-Y duodenal diversion despite abnormal acid reflux, as shown by 24-hour pH measurements, suggests that duodenal contents also have a role in the pathogenesis of esophagitis in an acid milieu.     

Gastroesophageal reflux disease in patients with columnar-lined esophagus

Columnar-lined esophagus or Barrett's esophagus is closely associated with gastroesophageal reflux disease. Animal and human studies have shown not only acid but duodenogastroesophageal reflux acting in synergy with acid causes the most esophageal injury. Patients with Barrett's esophagus manifest typical and atypical symptoms of reflux. Ten percent to 25%, however, have clinically silent reflux. Early diagnosis is essential for this disease as it is a risk factor for the development of adenocarcinoma of the esophagus.     

Laparoscopic Toupet fundoplication for gastroesophageal reflux disease with poor esophageal body motility

Impaired esophageal body motility is a complication of chronic gastroesophageal reflux disease (GERD). In patients with this disease, a 360-degree fundoplication may result in severe postoperative dysphagia. Forty-six patients with GERD who had a weak lower esophageal sphincter pressure and a positive acid reflux score associated with impaired esophageal body peristalsis in the distal esophagus (amplitude <30 mm Hg and >10% simultaneous or interrupted waves) were selected to undergo laparoscopic Toupet fundoplication. They were compared with 16 similar patients with poor esophageal body function who underwent Nissen fundoplication. The patients who underwent Toupet fundoplication had less dysphagia than those who had the Nissen procedure (9% vs.44%; P=0.0041). Twenty-four-hour ambulatory pH monitoring and esophageal manometry were repeated in 31 Toupet patients 6 months after surgery. Percentage of time of esophageal exposure to pH <4.0, DeMeester reflux score, lower esophageal pressure, intra-abdominal length, vector volume, and distal esophageal amplitude all improved significantly after surgery. Ninety-one percent of patients were free of reflux symptoms. The laparoscopic Toupet fundoplication provides an effective antireflux barrier according to manometric, pH, and symptom criteria. It avoids potential postoperative dysphagia in patients with weak esophageal peristalsis and results in improved esophageal body function 6 months after surgery.     

Biliary reflux can be a contributory cause of esophagitis

In recent years duodenogastric reflux has been recognised as a possible cause of oesophagitis. Alone or in combination, bile salts, trypsin, pepsin, and hydrochloric acid have all been shown to cause oesophagitis. Duodenal content in the oesophagus can be measured by means of a new fibre-optic sensor, Bilitech 2000, a device measuring the occurrence of bilirubin and yielding 24-hour readings from the distal oesophagus. Studies in which the device has been used have shown oesophageal bilirubin to be increased in patients with oesophagitis, especially in the subgroup with such complications as oesophageal stricture or ulceration, or Barrett's oesophagus. The evidence suggests that unsatisfactory response to proton pump inhibitors in reflux patients might be due to an increase in duodenal reflux, and should be treated surgically with fundoplication or biliary diversion. This may also be true of oesophagitis patients with complications, though this remains to be shown in clinical studies.     

Total duodenal diversion for treatment of reflux esophagitis uncontrolled by repeated antireflux procedures

The operations of Nissen, Hill, and Belsey are adequate in controlling esophaegeal reflux in the majority of patients. In a small percentage however, objective and subjective evidence of esophagitis persists in spite of repeated operations to restore lower esophageal sphincter competency. These failures are then usually treated by operative procedures of great magnitude involving organ interposition. Repeated antireflux operations directed to the gastroesophageal area may in some instances result in impairment of blood supply with an increased risk of both esophageal and gastric fistulae. In the past many observers have felt that reflux esophagitis resulted solely from the effects of acid-pepsin secretions bathing the distal esophagus. Recently experimental and clinical data have indicated the importance of duodenal contents in the etiology and perpetuation of reflux esophagitis. During a recent two year period, 6 patients with persistent reflux esophagitis uncontrolled by repeated antireflux procedures have been seen on our service. These 6 patients, underwent 12 unsuccessful antireflux operations elsewhere. Three of the 6 patients had also been subjected to vagotomy-antrectomy for a coexisting duodenal ulcer. A marked lowering of gastric acidity took place but esophageal reflux and esophagitis persisted. These three patients were treated on our service by takedown of the Billroth I anastomosis, closure of the duodenal stump and diversion of the duodenal contents into a Roux-en-Y limb. Three other patients who had undergone unsuccessful antireflux procedures alone were subjected to antral resection, Roux-en-Y diversion and transthoracid vagotomy. This simplified appraoch to the treatment of persistent esophageal reflux uncontrolled by repeated antireflux procedures has given satisfactory results. The operation should be considered when technical considerations preclude further surgical attempts to perform another effective antireflux operation. Total duodenal diversion should, however, not be considered as the primary operation for the patient suffering from reflux esophagitis. However, in circumstances discussed above this direct approach appears preferable to major resectional procedures.     

Complications of gastroesophageal reflux disease. Esophagitis, acid laryngitis, and beyond

Gastroesophageal reflux disease is a common disorder that can result in various esophageal and extraesophageal complications. Reflux of gastric contents can cause esophageal mucosal abnormalities, such as ulcers and peptic strictures, as well as pulmonary and otolaryngologic symptoms, including reflux-induced asthma and acid laryngitis. Left untreated, some complications can lead to more severe disorders, such as esophageal adenocarcinoma that develops in patients with Barrett's esophagus. Accurate recognition of these diverse manifestations allows improved identification of patients at risk for reflux-related disorders and aids in proper evaluation and treatment.     

Effect of pneumatic dilation on gastroesophageal reflux in achalasia

The aims of this study were to assess the effect of pneumatic dilation on gastroesophageal reflux in achalasia, differentiate esophageal acid due to lactate from acid due to gastroesophageal reflux, and determine if chest pain and heartburn are reliable indicators of gastroesophageal reflux. Eight untreated achalasia patients underwent pre- and postdilation esophageal fluid/food residue lactate and pH analysis, esophageal manometry, 24-hr pH monitoring, and symptom assessment. All patients had a successful clinical outcome and a decrease in lower esophageal sphincter pressure from 29.1 +/- 12.7 to 14.7 +/- 3.8 mm Hg (mean +/- SD; P = 0.04). Abnormal acid exposure was present in two patients before and two patients after dilation. Postdilation acid exposure was mild. Lactate was detected before dilation in all patients. A lactate concentration >2 mmol/liter was associated with acidic residue and one abnormal 24-hr pH profile. There was no correlation between an abnormal 24-hr pH test and age, lower esophageal sphincter pressure, or duration of symptoms prior to treatment. Chest pain and heartburn were unrelated to drops in pH. Gastroesophageal reflux is rare in untreated achalasia and esophageal acidity may result from ingestion of acidic foods or production of lactate. Mild gastroesophageal reflux occurs after dilation but is of no clinical significance. Chest pain and heartburn are not indicators of acid reflux in achalasia.     

Barrett's esophagus: pathogenesis, epidemiology, functional abnormalities, malignant degeneration, and surgical management

Barrett's esophagus (i.e. columnar epithelial metaplasia in the distal esophagus) is an acquired condition that in most patients results from chronic gastroesophageal reflux. It is a disorder of the white male in the Western world with a prevalence of about 1/400 population. Due to the decreased sensitivity of the columnar epithelium to symptoms, Barrett's esophagus remains undiagnosed in the majority of patients. Gastroesophageal reflux disease in patients with Barrett's esophagus has a more severe character and is more frequently associated with complications as compared with reflux patients without columnar mucosa. This appears to be due to a combination of a mechanically defective lower esophageal sphincter, inefficient esophageal clearance function, and gastric acid hypersecretion. Excessive reflux of alkaline duodenal contents may be responsible for the development of complications (i.e., stricture, ulcer, and dysplasia). Therapy of benign Barrett's esophagus is directed towards treatment of the underlying reflux disease. Barrett's esophagus is associated with a 30- to 125-fold increased risk for adenocarcinoma of the esophagus. The reasons for the dramatic rise in the incidence of esophageal adenocarcinoma, which occurred during the past years, are unknown. High grade dysplasia in a patient with columnar mucosa is an ominous sign for malignant degeneration. Whether an esophagectomy should be performed in patients with high grade dysplasia remains controversial. Complete resection of the tumor and its lymphatic drainage is the procedure of choice in all patients with a resectable carcinoma who are fit for surgery. In patients with tumors located in the distal esophagus, this can be achieved by a transhiatal en-bloc esophagectomy and proximal gastrectomy. Early adenocarcinoma can be cured by this approach. The value of multimodality therapy in patients with advanced tumors needs to be shown in randomized prospective trials.     

Treatment of reflux oesophagitis of moderate and severe grade with ranitidine or pantoprazole--comparison of 24-hour intragastric and oesophageal pH

BACKGROUND: Proton pump inhibiting drugs strongly decrease gastric acid secretion and have proven more effective in the treatment of reflux oesophagitis than H2-receptor antagonists. METHODS: In a double-blind randomized trial, 24 patients with oesophagitis grade II (n = 15) and III (n = 9) were treated for 4 weeks with either ranitidine 150 mg b.d. (n = 13) or pantoprazole 40 mg o.m. (n = 11). Before the trial and on the last day of medication, 24-h intragastric pH and oesophageal pH profiles were performed. Healing was assessed by endoscopy. RESULTS: Pantoprazole increased median gastric pH from 1.7 to 3.9. Virtually no change in gastric pH was seen in the ranitidine group. Pantoprazole reduced the fraction time of pH < 4 in the oesophagus from 21% to 3% (P = 0.0005), and the median number of refluxes from 206 to 56 (P = 0.022). Oesophageal acid exposure was not decreased by ranitidine. Healing of the oesophagitis was seen in 6/11 cases after pantoprazole and in 3/13 cases after ranitidine (N.S.) CONCLUSION: In patients with oesophagitis of moderate and severe grade, pantoprazole 40 mg o.m. decreases intragastric acidity and gastro-oesophageal acid reflux more effectively than ranitidine 150 mg b.d.     

Effects of oral rabeprazole on oesophageal and gastric pH in patients with gastro-oesophageal reflux disease

BACKGROUND: This study examined the dose-response effects of the new proton-pump inhibitor rabeprazole on oesophageal and gastric pH in patients with gastro-oesophageal reflux disease. METHODS: This study had a single-centre, double-blind, randomized, two-way crossover design. Twenty patients were treated for two 7-day periods separated by a 7-10-day washout period. Patients were randomly assigned to receive either 20 mg of rabeprazole once daily during the first treatment period and 40 mg once daily during the second treatment period, or 40 mg during the first treatment period and 20 mg during the second treatment period. The primary efficacy variable was oesophageal acid exposure determined by 24-hour ambulatory pH monitoring. Acid-reflux time was defined as the percentage of time over 24 h that oesophageal pH was < 4. A dosage was considered effective if reflux time was reduced to < 6%, a number which has been our internal laboratory reference. RESULTS: Both rabeprazole 20 mg and 40 mg, given once daily, normalized reflux time, with decreases of 79% and 92% in acid exposure by day 7. Both dosages also decreased the mean total number of reflux episodes and the number of episodes lasting > 5 min, with no significant differences between dosages for any reflux parameter. Mean gastric pH increased with 20 mg from 1.86 at baseline to 3.71 on day 1 and 4.17 on day 7. Rabeprazole 40 mg once daily increased gastric pH from 2.01 to 4.37 on day 1, and to 4.65 on day 7. Safety analyses revealed no significant acute side-effects for either dosage. CONCLUSIONS: Pathological oesophageal acid exposure was normalized with both 20 mg and 40 mg dosages of rabeprazole, and the effects of these two doses did not differ. Rabeprazole was well-tolerated in this short-term study.     

Duodenogastric reflux after gastric surgery and in gastric ulcer disease: continuous measurement with a sodium ion selective electrode

Duodenogastric reflux (DGR) was investigated with a sodium ion selective electrode in 10 normal controls, 10 patients with persistent pain after gastric surgery, and five patients with gastric ulcer. During an average study time of two and a half hours, normal controls had reflux for 12% of the study, whereas patients after gastric surgery had reflux for 91% of the study time (p < 0.0002). Patients with a gastric ulcer had reflux on average for 67% of the study (p < 0.001). The patients who had had gastric surgery had several symptoms, but there was no association between the number or nature of symptoms and the severity of DGR as determined by the sodium electrode. Patients with positive bile provocation tests did not show any significant difference in the duration of reflux compared with those with a negative provocation test (79% and 87%). There was also no relation between the results of the provocation test and the number and nature of symptoms. Continuous monitoring of intragastric sodium ions with a selective electrode is a practical means of assessing DGR. Results suggest that symptoms due to DGR may be related to the sensitivity of the gastric lining as well as the amounts of duodenal contents flowing back into the stomach.     

Esophageal cancer on the increase. Is Barrett esophagus the cause?

At the Dept of Surgery, Lund University, during the 10-year period 1985-95, 54 patients with adenocarcinoma of the gastro-oesophageal junction (17 with Barrett's epithelium, and 37 without) underwent oesophageal resection: oesophagectomy and gastric pull-up (n = 10), extended total gastrectomy (n = 37), or oesophageal resection and interposition of colon (n = 2) or jejunum (n = 5). Hospital mortality was 3.7% (2/54), and the mean duration of hospitalisation 13 days (range, 9-42). Long-term survival was significantly better in the Barrett's oesophagus subgroup than in the carcinoma of the cardia (non-Barrett's oesophagus) subgroup, the respective rates being 50% vs. 10% (p = 0.0052; Log rank test). The better survival in the Barrett's oesophagus subgroup is probably to be explained by the earlier stage of disease among these patients, in turn due to a history of gastro-oesophageal reflux, whereas the predominant symptom in the cardia carcinoma subgroup was dysphagia.     

Gastroesophageal reflux disease: pathophysiology, diagnosis and drug therapy

The principal mechanism leading to gastro-oesophageal reflux is an increased frequency of transient lower oesophageal sphincter relaxations; other factors are oesophageal hypersensitivity to gastric juice, hiatus hernia, and possible duodenal reflux. Patients with classical symptoms such as heartburn and regurgitation may be treated pharmaceutically combined with life style counselling. If the symptoms have not improved after 6 to 12 weeks, endoscopical examination is performed and, if necessary, 24-hour pH monitoring, barium radiographing and manometry. In the case of atypical symptoms such as dysphagia, laryngitis, asthma and chest pain, there is more reason to pursue diagnostic testing. In patients with dysphagia endoscopy is indicated to exclude malignancy. Drug treatment can be subdivided into antacids, H2 receptor antagonists, cytoprotective agents, prokinetics and proton pump inhibitors. In general practice a step-up approach to treatment is preferable, while for specialist treatment a stepdown approach is more (cost-)effective. Drawbacks of medical treatment are considerable frequency of recurrence of oesophagitis, persistence of regurgitation in 'volume refluxers' and controversial data on the possible development of (pre)malignant lesions of oesophagus and stomach. Surgical treatment is a good alternative for patients with persistent severe regurgitation during medical therapy and for young patients who prefer surgery to lifelong medication. Patients with Barrett's oesophagus should undergo regular endoscopic biopsy surveillance.     

A prospective assessment of gastroesophageal reflux before and after treatment of achalasia patients: pneumatic dilation versus transthoracic limited myotomy

OBJECTIVES: We conducted this study to determine whether reflux should be a major consideration in the choice of treatment for achalasia patients. Achalasia patients undergoing either pneumatic dilation or transthoracic limited esophagomyotomy were monitored for reflux before and after treatment, for comparison. METHODS: Twenty-four hour ambulatory esophageal pH tests and esophageal manometry were performed on 32 consecutive, untreated achalasia patients. Studied (before and after treatment) were 17 patients who underwent pneumatic dilation and 15 patients who received transthoracic limited myotomy without fundoplication. All follow-up studies were completed within 12 months of treatment. RESULTS: The ages of the two groups were not significantly different (p > 0.05, 45 +/- 9 yr myotomy vs. 44 +/- 13 yr dilation). The resting lower esophageal sphincter pressure was not significantly different (p > 0.05 before treatment) between groups but was reduced significantly (p < 0.05 after treatment) in both groups (30 +/- 9 mm Hg before vs. 9 +/- 4 mm Hg after myotomy, and 27 +/- 10 mm Hg before vs. 11 +/- 4 mm Hg after pneumatic dilation. The total time the pH was < 4.0 was not significantly different, p > 0.05, in either group before treatment (myotomy, 3.7 +/- 4.4%; dilation, 2.9 +/- 4.9%) or after treatment (myotomy, 8.6 +/- 9.2%; dilation, 10.2 +/- 15.9%). Twelve of 32 patients (38%), had a percent total time < 4.0 that exceeded 6% after treatment, eight of whom were asymptomatic. CONCLUSIONS: These results indicate that the amount of reflux after treatment by both pneumatic dilation and transthoracic esophagomyotomy is similar. The absence of reflux symptoms in treated achalasia patients does not exclude the possibility of significant acid reflux.     

Esophageal function in systemic sclerosis: a prospective evaluation of motility and acid reflux in 36 patients

Systemic sclerosis (SSc) is a connective tissue disorder which frequently involves the esophagus, with severe gastroesophageal reflux (GER) and dysphagia as clinical consequences of esophageal dysmotility. The relationship between the severity and extent of esophageal acid exposure and the specific manometric disturbances has received little attention. Similarly, a paucity of manometric data exists regarding pharyngeal/upper esophageal sphincter (UES) function in SSc patients. We prospectively studied 36 SSc patients using computerized solid-state manometric and ambulatory dual-pH (upper and lower esophageal) monitoring, to define further the relationship between esophageal dysmotility and severity of GER in these patients. Patients were separated for analysis into two subgroups based on the absence (group 1, N = 25) or presence (group 2, N = 11) of distal esophageal peristalsis. SSc disease variant (diffuse vs. limited) and duration of illness were inaccurate predictors of the presence and severity of esophageal involvement. The mean lower esophageal sphincter (LES) pressure for the SSc patients (15.8 +/- 1.2 mm Hg, mean +/- SE) was significantly lower (p < 0.01) than that for a control group (26.0 +/- 2.1 mm Hg). There was no significant difference between the mean LES pressure for group 1 (15.0 +/- 1.6 mm Hg) and group 2 (17.5 +/- 1.6 mm Hg) patients. Although distal esophageal aperistalsis was noted in 70% of patients, normal proximal esophageal contraction pressures were documented in all cases. Mean UES pressure was significantly (p < 0.01) lower in group 1 (52.5 +/- 4.6 mm Hg) than in group 2 (80.5 +/- 10.6 mm Hg). The mean duration of UES relaxation and the mean time interval between the onset of UES relaxation and onset of pharyngeal contraction were significantly (p < 0.05) shorter for group 1 than group 2 patients. Pharyngeal pressures, peristalsis, and other aspects of pharyngeal/UES coordination were normal. Excessive distal esophageal acid exposure was often seen in patients in both subgroups, but it was significantly (p < 0.01) greater in group 1. Excessive proximal esophageal acid exposure was documented only in patients with absent distal peristalsis. Linear regression analysis revealed a poor correlation between the severity of esophageal acid exposure and the LES pressure. Thus, the severity and extent of GER in SSc is most closely related to the integrity of distal esophageal peristalsis.     

Protein and RNA synthesis in larvae of the yellow mealworm beetle (Tenebrio molitor) during cooling and cold acclimatization

Adult patients with symptoms of gastric disease were randomly assigned to two treatment groups (roxatidine group, n = 115; famotidine group, n = 113) or untreated control group (placebo, n = 111). The treatment groups randomly received 75 mg of roxatidine or 20 mg of famotidine at 9 pm, and 12 - 13 h later gastric juice secretion was measured with gastric X-ray films in both groups. Mean gastric juice secretion was significantly lower in the treated groups (roxatidine, 16.1 ml/12 h; famotidine, 19.9 ml/12 h) than in the untreated controls (placebo, 49.5 ml/12 h). Gastric juice suppression by roxatidine and by famotidine, respectively, was 82% and 37% in patients with gastric ulcer; 71% and 39% in patients with duodenal ulcer; 70% and 64% in patients with gastritis; and 68% and 86% in patients with no evidence of disease. It is concluded that roxatidine was more effective than famotidine for gastric juice suppression in patients with peptic ulcer. In patients with no evidence of gastric disease, however, famotidine was more effective than roxatidine.