Biomedical subjects

J H Peters

Publications and source records attributed to J H Peters.

At least 73 records · Page 4Linked to original sources

PubMed1999

[The physiopathological basis for Zenker's diverticulum].

Disorders of the pharyngoesophageal phase of swallowing, including Zenker's diverticulum, result from alterations of the neuromuscular events involved in chewing, initiation of swallowing, and propulsion of the material from the oropharynx into the cervical esophagus. Although a number of mechanisms have been postulated to explain the genesis of Zenker's divertcula, including sphincter incoordination, swallowing against a closed UES, failed UES relaxation, and a hypertensive spastic upper sphincter, recent evidence suggests that the pathophysiology of Zenker's diverticula involves altered compliance of the cricopharyngeal segment. Manometric relaxation may occur in the absence of anatomic opening. Incoordination is uncommon. Altered compliance is detectable with specialized cricopharyngeal manometric recording as impaired sphincter opening or a raised intrabolus pressure. Both return to normal following diverticulectomy and cricopharyngeal myotomy.

Humans↗

PubMed1999

The extent of Barrett's esophagus depends on the status of the lower esophageal sphincter and the degree of esophageal acid exposure.

OBJECTIVE: The purpose of this study was to assess whether the extent of intestinal metaplasia is related to the severity of the gastroesophageal reflux disease. METHODS: A total of 556 consecutive patients with symptoms suggestive of foregut disease had upper gastrointestinal endoscopy with extensive biopsies from the gastroesophageal junction and the esophagus. All patients had esophageal motility and 24-hour pH monitoring. In 411 patients, cardiac-type mucosa was identified; in 147 patients, the cardiac-type mucosa showed intestinal metaplasia. They were divided into 3 groups based on the extent of intestinal metaplasia commonly seen clinically: long segments (>3 cm), short segments (<3 cm), and limited to the gastroesophageal junction. The duration of symptoms, the status of the lower esophageal sphincter, the degree of esophageal acid exposure, and the time to clear a reflux episode were assessed in each group. RESULTS: The presence of intestinal metaplasia in cardiac-type mucosa was associated with the hallmarks of gastroesophageal reflux disease. The extent of intestinal metaplasia correlated strongly with the degree of esophageal acid exposure (r = 0.711; P <.001) and inversely with the lower esophageal sphincter pressure (r = 0.351; P <.001) and length (r = 0. 259; P =.002). Patients with a long segment of intestinal metaplasia (>3 cm) had longer duration of symptoms (16 years) than those patients with a segment of intestinal metaplasia less than 3 cm (10 years; P =.048) or those patients with intestinal metaplasia limited to the gastroesophageal junction (10 years; P =.01). CONCLUSION: The extent of intestinal metaplasia, that is, Barrett's esophagus, is related to the status of the lower esophageal sphincter and the degree of esophageal acid exposure.

Adolescent↗

PubMed1999

Node status in transmural esophageal adenocarcinoma and outcome after en bloc esophagectomy.

OBJECTIVE: Adenocarcinoma has replaced squamous cell as the most common esophageal cancer in the United States. The purpose of this study was to determine the prevalence and location of lymph node metastases, the feasibility of performing an R0 resection, and disease recurrence and survival in patients with transmural adenocarcinoma of the lower esophagus and gastroesophageal junction. METHODS: Forty-four patients with transmural adenocarcinoma underwent en bloc esophagectomy with systematic thoracic and abdominal lymphadenectomy. They were followed up for a median of 23 months. RESULTS: Actuarial survival for the entire group was 26% at 5 years. The most important predictors of the likelihood of recurrent disease and 5-year survival were the presence and number of lymph node metastases and the ratio of involved to total removed nodes. Seven patients (16%) were found to have no lymph node metastases and had an 85% 5-year survival. In contrast, patients with more than 4 involved nodes or a node ratio greater than 0.1 had a high likelihood of recurrence and death. Location of involved lymph nodes did not predict the likelihood of recurrence or death. Despite all patients having transmural tumors, recurrence within the field of the en bloc resection occurred in only 1 patient (2%). CONCLUSIONS: En bloc esophagectomy in patients with transmural esophageal adenocarcinoma is required to obtain the survival benefit of an R0 resection, to adequately assess lymphatic tumor burden, and to be able to predict the likelihood of recurrence and death and thereby guide the use of postoperative adjuvant therapy.

Abdomen↗

PubMed1999

Prevalence and location of nodal metastases in distal esophageal adenocarcinoma confined to the wall: implications for therapy.

OBJECTIVE: The purpose of this study was to characterize the prevalence and location of regional lymph node metastases in adenocarcinoma confined to the esophagal wall, to determine the extent of dissection required, and to investigate the applicability of nonoperative therapy. METHODS: Histologic evaluation of the resected specimens after en bloc esophagogastrectomy with mediastinal and abdominal lymphadenectomy was performed on 37 patients with adenocarcinoma confined to the esophageal wall. Follow-up was complete in all patients (median 24 months). RESULTS: Fifteen patients (41%) had intramucosal tumors. Twelve (32%) had submucosal tumors and 10 (27%) had muscular invasion. The prevalence of regional lymph node metastases (15/37 patients, 41%) increased progressively with depth of tumor invasion, with involved nodes identified in 80% of patients with muscular invasion. Lymph node metastases were also more common at distant node stations in intramuscular tumors (5/10, 50%). Actuarial survival for the entire group was 63% at 5 years. Recurrence was identified in 6 of the 37 patients (16%), with the risk of recurrence correlating with tumor depth. CONCLUSIONS: Tumor depth is a strong predictor of the probabilities of regional lymph node metastases, the likelihood of involvement of distant node groups, and the risk of recurrence. Patients with invasion of the muscular wall are at particularly high risk. En bloc esophagectomy with mediastinal and abdominal lymphadenectomy has the highest likelihood of achieving an R0 resection. The long-term survival and low recurrence rate achieved with an en bloc esophagectomy emphasizes the importance of an aggressive lymph node dissection to remove all potentially involved nodes.

Adenocarcinoma↗

PubMed1999

Current state, techniques, and results of laparoscopic antireflux surgery.

The introduction of laparoscopic fundoplication has dramatically changed the face of antireflux surgery. Central to the success of laparoscopic fundoplication is careful preoperative patient evaluation and attention to surgical technique. Emerging evidence has questioned the long-term durability of laparoscopic partial fundoplications underscoring the place of laparoscopic Nissen fundoplication as the procedure of choice for most patients. The technique of laparoscopic Nissen fundoplication should incorporate crural closure, complete fundic mobilization by short gastric vessel division, and the creation of a short, loose fundoplication by enveloping the anterior and posterior fundic walls around the esophagus. Relief of typical reflux symptoms can be anticipated in over 90% of patients. The outcome of atypical reflux symptoms is less predictable, on average two thirds of patients benefiting. The cost of laparoscopic fundoplication compares favorably to long-term medical therapy and open fundoplication. Current trends indicate that laparoscopic fundoplication is being used increasingly as an alternative to long-term medical therapy.

Costs and Cost Analysis↗

PubMed1999

Occult esophageal adenocarcinoma: extent of disease and implications for effective therapy.

OBJECTIVE: The need for esophagectomy in patients with Barrett's esophagus, with no endoscopically visible lesion, and a biopsy showing high-grade dysplasia or adenocarcinoma has been questioned. Recently, endoscopic techniques to ablate the neoplastic mucosa have been encouraged. The aim of this study was to determine the extent of disease present in patients with clinically occult esophageal adenocarcinoma to define the magnitude of therapy required to achieve cure. METHODS: Thirty-three patients with high-grade dysplasia (23 patients) or adenocarcinoma (10 patients) and no endoscopically visible lesion underwent repeat endoscopy and systematic biopsy followed by esophagectomy. The surgical specimens were analyzed to determine the biopsy error rate in detecting occult adenocarcinoma. In those with cancer, the depth of wall penetration and the presence of lymph node metastases on conventional histology and immunohistochemistry staining was determined. The findings were compared with those in 12 patients (1 with high-grade dysplasia, 11 with adenocarcinoma) who had visible lesions on endoscopy. RESULTS: The biopsy error rate for detecting occult adenocarcinoma was 43%. Of 25 patients with cancer and no visible lesion, the cancer was limited to the mucosa in 22 (88%) and to the submucosa in 3 (12%). After en bloc esophagectomy, one patient without a visible lesion had a single node metastasis on conventional histology. No additional node metastases were identified on immunohistochemistry. The 5-year survival rate after esophagectomy was 90%. Patients with endoscopically visible lesions were significantly more likely to have invasion beyond the mucosa (9/12 vs. 3/25, p = 0.01) and involvement of lymph nodes (5/9 vs. 1/10, p = 0.057). CONCLUSIONS: Endoscopy with systematic biopsy cannot reliably exclude the presence of occult adenocarcinoma in Barrett's esophagus. The lack of an endoscopically visible lesion does not preclude cancer invasion beyond the muscularis mucosae, cautioning against the use of mucosal ablative procedures. The rarity of lymph node metastases in these patients encourages a more limited resection with greater emphasis on improved alimentary function (esophageal stripping with vagal nerve preservation) to provide a quality of life compatible with the excellent 5-year survival rate of 90%.

Adenocarcinoma↗

PubMed1999

Current concepts in the management of paraesophageal hiatal hernia.

Herniation of a portion of the stomach through the esophageal hiatus into the posterior mediastinum is a common affliction of humans. The incidence of hiatal hernia is difficult to determine because of the absence of symptoms in a large number of patients. Upper gastrointestinal barium examinations in symptomatic patients identify some type of hiatal hernia in as many as 15% of patients.

Fundoplication↗

PubMed1999

Biology of gastroesophageal reflux disease: pathophysiology relating to medical and surgical treatment.

This chapter reviews the biology of gastroesophageal reflux disease, relating pathophysiology to medical and surgical therapy. Various definitions of the disease are presented and workable criteria are developed to identify patients with the disease. The central importance of the lower esophageal high-pressure zone as a barrier to reflux is emphasized, along with an analysis of its biomechanical alteration in disease. The composition of the refluxed gastric juice is characterized in regard to its potential for mucosal injury. Evidence is provided that cardiac-type mucosa is an acquired sequel to acid-induced squamous mucosal injury in the terminal esophagus. A hypothesis regarding the process of intestinalization of cardiac-type mucosa to form Barrett's esophagus is presented. An integrated concept of the pathophysiology of gastroesophageal reflux disease is constructed. Practical concepts regarding the treatment of gastroesophageal reflux disease are developed, based on a review of studies on the natural history of the disease and the long-term outcome of therapy.

Barrett Esophagus↗

PubMed1999

Are the motility abnormalities of achalasia reversible? An experimental outflow obstruction in the feline model.

BACKGROUND: Experimental and clinical evidence suggests that the loss of esophageal body function in achalasia may be a result of the outflow obstruction of a nonrelaxing, hypertensive lower esophageal sphincter. The reversibility of such abnormalities has implications to the timing of therapeutic interventions. This study was designed to evaluate the evolution and reversibility of motility abnormalities resulting from esophageal outflow obstruction in cats. METHODS: Twenty adult cats were divided into 2 groups. Group 1 consisted of 4 cats that underwent laparotomy as a sham procedure. Group 2 consisted of 16 cats that underwent surgical placement of a loose Gore-tex expanded polytetrafluoroethylene (W. L. Gore, Elkton, Md) band calibrated to 110% of the circumference of the gastroesophageal junction. The band was removed from 4 randomly selected cats each at 1, 2, 4, and 6 weeks after placement. Esophageal manometry was performed before placement of the band, at weekly intervals after placement of the band, and after removal of the band. The resting pressure and percent relaxation of the lower esophageal sphincter (LES), in addition to amplitude, duration, and propagation of esophageal body contractions, were measured at each interval. Data are expressed as median and interquartile range and compared with use of the Mann-Whitney U test for independent samples. RESULTS: The LES resting pressure remained unchanged after placement of the band, but sphincter compliance was reduced, as manifested by a significant reduction in the percent of sphincter relaxation (98% prebanding, 65% postbanding, P < .05). The median amplitude of esophageal contraction decreased significantly after banding. By 6 weeks after banding the esophagus was markedly dilated and exhibited aperistaltic, low-amplitude esophageal motility typical of that seen in clinical achalasia. Importantly, removal of the bands resulted in a prompt return of both peristalsis and amplitude of contraction. CONCLUSIONS: Loss of compliance of the lower esophageal sphincter produces outflow obstruction with the resultant loss of esophageal contraction amplitude and peristaltic waveform typical of achalasia in humans. These abnormalities were reversible after relief of obstruction in the feline model and may indicate that early relief of outflow obstruction in clinical achalasia may preserve esophageal function in patients.

Animals↗

PubMed1999

Abnormal esophageal body function: radiographic-manometric correlation.

Stationary manometry is the gold standard for the evaluation of patients with suspected esophageal motility disorders. Comparison of videoesophagram in the evaluation of esophageal motility disorders with stationary motility has not been objectively studied. Two hundred two patients with foregut symptoms underwent stationary motility and videoesophagram. Radiographic assessment of esophageal motility was done by video recording of five 10-cc swallows of barium. Abnormal esophageal body function was defined by stasis of barium in the middle third of the esophagus on at least four swallows or stasis on at least three swallows in the distal third. Stationary manometry was performed using a five-channel water perfused system. Contraction amplitudes <25 mm Hg in any of the last two channels or the presence of simultaneous or interrupted waves in 10 per cent or more were considered to be abnormal. Sixty-two patients had abnormal manometry. Thirty-four patients also demonstrated abnormal videoesophagrams for an overall sensitivity of 55 per cent. The positive predictive value was 53 per cent; specificity was 79 per cent; and negative predictive value was 80 per cent. Sensitivity was greatest in patients with achalasia (94%) and scleroderma (100%) and in patients presenting with dysphagia (89%). Sensitivity was poor for nonspecific esophageal motility disorders. A videoesophagram is relatively insensitive in detecting motility disorders. It seems most useful in the detection of patients with esophageal dysfunction, for which surgical treatment is beneficial, and in those patients presenting with dysphagia.

Adolescent↗

PubMed1998

Treatment of advanced gastroesophageal reflux disease with Collis gastroplasty and Belsey partial fundoplication.

OBJECTIVE: To examine the factors affecting outcome in patients with advanced gastroesophageal reflux disease. DESIGN: Retrospective analysis. SETTING: University tertiary referral center. PATIENTS: Thirty-seven patients with advanced gastroesophageal reflux disease and no previous antireflux surgery. INTERVENTIONS: Thirty patients underwent Collis gastroplasty for esophageal lengthening and Belsey partial fundoplication. Seven patients with esophageal stricture and global loss of esophageal body motility who underwent primary esophagectomy and reconstruction were used as a comparison group. OUTCOME MEASURES: Symptomatic outcome in all 37 patients was assessed by questionnaire at a median of 25 months (range, 5-156 months) after surgery. In a subset of 11 patients undergoing the Collis-Belsey procedure, outcome was measured using 24-hour pH and results of motility studies. RESULTS: The Collis-Belsey procedure was successful in relieving symptoms of gastroesophageal reflux in 21 (70%) of the 30 patients. The outcome was excellent or good in 16 (89%) of 18 patients who presented with symptoms other than dysphagia, but only in 5 (42%) of 12 patients with dysphagia (P = .01). The outcome was particularly poor if dysphagia was associated with a previously dilated esophageal stricture. Persistent or induced dysphagia was the reason for failure in all but 1 patient. Results of 24-hour esophageal pH studies were returned to normal in 8 (73%) of 11 patients undergoing postoperative evaluation. Contraction amplitudes in the distal esophagus and the prevalence of simultaneous contractions in these segments did not change after the operation. All 7 patients who underwent primary esophagectomy were classified as having an excellent or good outcome and were relieved of their reflux symptoms, including dysphagia. Six of these could eat 3 meals per day and enjoyed an unrestricted diet. CONCLUSIONS: The outcome of the Collis-Belsey procedure in patients with advanced gastroesophageal reflux disease without dysphagia is excellent. It is less so in patients with dysphagia as a preoperative symptom. Esophagectomy can provide a good outcome in patients who have a combination of dysphagia stricture and a profound loss of esophageal motility.

Adult↗

PubMed1998

Patient response to marketing minimally invasive surgery for heartburn.

BACKGROUND: Over 40% of Americans suffer from "heartburn" at least once a month. This and other manifestations of gastroesophageal reflux (GERD) are often treated with neglect by both patients and their primary care physicians. Diagnostic evaluation is all too often sought only in late stages of the disease. We studied the response to a media campaign promoting minimally invasive surgery as a cure for longstanding heartburn. METHODS: The information was publicized on 14 TV and six radio stations over 4 weeks. Patients were referred to an 800-number and data on the following topics were obtained using a standardized questionnaire: demographics, reflux symptoms, previous specialist referral, diagnostic evaluation and treatment, insurance information, and reasons for and expectations in calling. All questionnaires were screened for likelihood of GERD (high, medium, low). A return call was placed to triage patients (surgical or medical appointment, information only, no contact). RESULTS: We received calls from 1,389 potential patients. Based on symptoms, medical therapy, and previous evaluation, 891 (64%) were judged to likely have GERD and assigned high-priority status. Of the patients providing insurance information, 32% were enrolled in an HMO; 29% commercial; 16% Medicare; 14% employer based; and 9% had no insurance. Six hundred ninety-eight high-priority patients were contacted. Of these, 402 (58%) wanted information only; 228 (33%) desired surgical and 68 (%) medical appointments. Two hundred fifteen patients (16% of callers) were seen by a surgical or medical consultant. One hundred thirty-five underwent diagnostic studies, of which 77 (57%) had pathologic esophageal acid exposure. Eighty-three patients have undergone surgery to date-60 laparoscopic and 14 open antireflux procedures; nine had other surgical procedures. CONCLUSIONS: Surprisingly, 64% of patients responding to a marketing campaign for heartburn have typical symptoms of GERD, have consulted one or more physicians and/or received medical treatment. More than half the patients tested (77/135) were found to have a positive 24-h pH study, and 78% (60/77) of these elected antireflux surgery to control their reflux symptoms.

Gastroesophageal Reflux↗

PubMed1998

Ultrasonic epithelial ablation of the lower esophagus without stricture formation. A new technique for Barrett's ablation.

BACKGROUND: The premalignant potential of Barrett's esophagus has stimulated efforts to find a way to ablate the columnar epithelium in order to reheal the area with squamous epithelium, thus obviating the cancer risk. This study describes and evaluates a new technique using ultrasonic energy to ablate the epithelium of the lower esophagus in a porcine model. METHODS: Eight young farm pigs were used to develop the technique of applying a laparoscopic Cavitron Ultrasonic Surgical Aspirator (CUSA) to the lower esophageal mucosa through an operating gastrostomy. A further 11 Yakutan minipigs then underwent CUSA epithelial ablation, followed by a laparoscopic Nissen fundoplication or postoperative acid suppression therapy. We then assessed the healing response in these subjects. RESULTS: Optimal CUSA energy settings enabled complete ablation of the squamous epithelium with preservation of the muscularis mucosa and submucosa. The integrity of the aspirated cells was sufficient for cytological analysis. Healing occurred by squamous regeneration without stricture formation. CONCLUSION: The CUSA technique holds promise for complete ablation of the Barrett's epithelium in a single setting. The unique tissue-selective nature of the ablative process allows complete mucosal reepithelialization without stricture formation.

Animals↗

PubMed1998

Esophageal replacement for end-stage benign esophageal disease.

BACKGROUND: Benign esophageal diseases constitute a common group of disorders that are generally managed with medical therapy or surgery designed to improve foregut function. A small subset of patients, however, has advanced disease that requires esophageal replacement to achieve symptomatic relief. PATIENTS AND METHODS: One hundred four patients with benign esophageal disease who underwent esophageal reconstruction over a 21-year period (1975 to 1996) were reviewed retrospectively. Dysphagia was the major symptom driving surgery in 80% of the patients. Colon was used to reconstruct the esophagus in 85 patients; stomach, in 10 patients; and jejunum, in 9 patients. Forty-two patients who had lived with their reconstruction for 1 year or more answered a postoperative questionnaire concerning their long-term functional outcome. RESULTS: In the 104 patients, the primary underlying abnormality leading to esophageal replacement was end-stage gastroesophageal reflux (37 patients), an advanced motility disorder (37 patients), traumatic, iatrogenic or spontaneous perforation (15 patients), corrosive injury (8 patients), congenital abnormality (6 patients), or extensive leiomyoma (1 patient). Ninety-eight percent of patients reported that the operation had cured or improved the symptom driving surgery. Ninety-three percent were satisfied with the outcome of the operation. The overall hospital mortality rate was 2%, and the median hospital stay was 17 days. Graft necrosis occurred in 3% of patients, and anastomotic leak occurred in 6% of patients (or 2% of the total number of anastomoses). CONCLUSIONS: Esophageal replacement for benign disease can be accomplished with a low mortality rate and a marked improvement in alimentation. Reconstruction restores the pleasure of eating and is viewed by the patient to be highly successful.

Adolescent↗

PubMed1998

Esophagectomy for unsuccessful antireflux operations.

BACKGROUND: Primary antireflux surgery provides excellent symptom relief in most patients. Unfortunately, the results of redo surgery are less predictable. In these patients, esophageal injury from long-standing reflux of gastric contents and operative trauma from previous failed antireflux procedures results in progressive deterioration in esophageal propulsion, poor clearance of reflux episodes, mucosal damage, and, in some cases, stricture formation. For the past 16 years, we have selectively used esophageal resection and replacement instead of another reoperation in these challenging patients. METHODS: Seventeen patients with end-stage esophageal body dysfunction and one or more previously unsuccessful antireflux procedures underwent esophagectomy and reconstruction by colon interposition in 15 patients and jejunum interposition in 2 patients. The indications for esophagectomy rather than a redo antireflux procedure were a global loss of effective esophageal motility in 13 and a nondilatable stricture in four. Their outcome was compared with that of 32 patients with adequate motility and 18 with a similar global loss of motility who had a redo antireflux procedure. Perioperative complications after esophagectomy were recorded, and long-term outcome was assessed by means of a standardized questionnaire at a median of 7 years after the operation. RESULTS: Patients with profound esophageal body dysfunction who underwent esophageal resection had outcomes similar to those with normal motility who underwent a redo antireflux procedure. Those with profound esophageal motility dysfunction who underwent a redo antireflux procedure had a worse outcome than those who underwent resection. Esophageal resection and replacement was performed without mortality or graft failure. All patients who underwent resection stated that their preoperative symptoms were relieved completely (n = 6) or improved (n = 10). Thirteen patients (81%) were able to eat three meals a day, and 12 patients (75%) enjoyed an unrestricted diet. Two thirds of the patients were at or above their ideal body weight, and 88% were fully satisfied with the outcome of the procedure. CONCLUSION: Patients with end-stage esophageal body dysfunction who have had a previous unsuccessful antireflux procedure can be treated by esophageal resection with a high expectation of success.

Adult↗

PubMed1998

Specific autologous anti-melanoma T cell response in vitro using monocyte-derived dendritic cells.

Dendritic cells (DC) are antigen-presenting cells initiating primary and secondary immune responses. Since malignant tumors are able to escape immunologic control, DC might be prime candidates to activate the immune system against tumor cells. In an autologous system, a dynamic interaction among monocyte-derived DC (MoDC), T lymphocytes, and tumor cells obtained from melanoma patients could be noted. MoDC were generated from blood monocytes in the presence of GM-CSF, IL-4, and IFN-gamma. T cells were isolated either from peripheral blood or from lymph nodes. Melanoma cells were harvested from surgically removed tumor metastases. They were then gamma-irradiated and co-cultured with autologous MoDC and T lymphocytes. After 5 days, the lymphocytes showed a high proliferative activity and the majority of them were CD8-positive. In five cases tested, they revealed a high cytotoxic activity resulting in apoptosis of tumor cells. These findings suggest that MoDC are capable of initiating an effective specific anti-tumor response in a strictly autologous mixed lymphocyte tumor culture (MLTC), even though tumor-specific antigens had not been individually defined. Therefore (I) whole melanoma cells can serve as a source of antigen, (II) monocyte-derived dendritic cells may process and present melanoma-specific antigens resulting in a strong lymphocyte proliferation, (III) the majority of responding T lymphocytes are CD8-positive, and (IV) an acquired cytotoxic response eventually leads to apoptosis of the melanoma cells. The reaction demonstrated here permits to in vitro and quantitatively monitoring the effect of T cell directed immunotherapies such as the adoptive immunotherapy of tumors.

Cell Differentiation↗

PubMed1998

Focussing human B cell specificity by immunoselection via antigen-presenting cells in vitro.

We present a protocol for in vitro immunization of B cells using monocyte-derived accessory cells (MoAC). MoAC are developed from human peripheral blood monocytes in culture and represent functionally competent inducers of antigen-specific immune responses. Using MoAC, we attempted to immunoselect TT-specific lymphocytes by rosetting. Adherent human MoAC were pulsed with tetanus toxoid (TT) and allowed to form clusters with autologous lymphocytes, followed by removal of non-adherent cells. After one week of culture, a specific anti-TT antibody response emerged on a low background of unspecific Ig. In comparison, cultures which had not been selected for adherent cells produced a high polyclonal background. Our results demonstrate that from peripheral blood cells, previously not a favourable source for in vitro immunization, in a majority of tests antigen-specific B cells could efficiently be immunoselected via adherence to autologous antigen-presenting cells, leading to a high-titre in vitro immunization.

Antibody Specificity↗

PubMed1998

The treatment of gastroesophageal reflux disease with laparoscopic Nissen fundoplication: prospective evaluation of 100 patients with "typical" symptoms.

OBJECTIVE: To evaluate prospectively the outcome of laparoscopic fundoplication in a large cohort of patients with typical symptoms of gastroesophageal reflux. SUMMARY BACKGROUND DATA: The development of laparoscopic fundoplication over the past several years has resulted in renewed interest in the surgical treatment of gastroesophageal reflux disease (GERD). METHODS: One hundred patients with typical symptoms of GERD were studied. The study was limited to patients with positive 24-hour pH studies and "typical" symptoms of GERD. Laparoscopic fundoplication was performed when clinical assessment suggested adequate esophageal motility and length. Outcome measures included assessment of the relief of the primary symptom responsible for surgery; the patient's and the physician's evaluation of outcome; quality of life evaluation; repeated upper endoscopy in 30 patients with presurgical esophagitis; and postsurgical physiologic studies in 28 unselected patients, consisting of 24-hour esophageal pH and lower esophageal sphincter manometry. RESULTS: Relief of the primary symptom responsible for surgery was achieved in 96% of patients at a mean follow-up of 21 months. Seventy-one patients were asymptomatic, 24 had minor gastrointestinal symptoms not requiring medical therapy, 3 had gastrointestinal symptoms requiring medical therapy, and 2 were worsened by the procedure. Eighty-three patients considered themselves cured, 11 were improved, and 1 was worse. Occasional difficulty swallowing not present before surgery occurred in 7 patients at 3 months, and decreased to 2 patients by 12 months after surgery. There were no deaths. Clinically significant complications occurred in four patients. Median hospital stay was 3 days, decreasing from 6.3 in the first 10 patients to 2.3 in the last 10 patients. Endoscopic esophagitis healed in 28 of 30 patients who had presurgical esophagitis and returned for follow-up endoscopy. Twenty-four-hour esophageal acid exposure had returned to normal in 26 of 28 patients studied after surgery. Lower esophageal sphincter pressures had also returned to normal in all patients, increasing from a median of 5.1 mmHg to 14.9 mmHg. CONCLUSIONS: Laparoscopic Nissen fundoplication provides an excellent symptomatic and physiologic outcome in patients with proven gastroesophageal reflux and "typical" symptoms. This can be achieved with a hospital stay of 48 hours and a low incidence of postsurgical complications.

Fundoplication↗