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D Rex

Publications and source records attributed to D Rex.

18 recordsLinked to original sources
PubMed2006

The Aer-O-Scope: proof of the concept of a pneumatic, skill-independent, self-propelling, self-navigating colonoscope in a pig model.

BACKGROUND AND STUDY AIMS: Considerable training is needed to enable endoscopists to use the currently available commercial colonoscopes and sigmoidoscopes effectively and safely. The aim of this study was to evaluate the safety and efficacy of the propulsion mechanism incorporated into the Aer-O-Scope (GI View Ltd., Ramat Gan, Israel)--a novel self-propelled, self-navigating colonic endoscope for diagnostic purposes. MATERIALS AND METHODS: Twenty young female pigs underwent complete bowel preparation followed by a sedated examination using the new device. Ten pigs underwent two consecutive procedures, with a wash-out period of 7 days between each procedure. The total number of procedures was 30. Two prototypes of the Aer-O-Scope, with different cable lengths and vehicle balloon sizes (n = 20 and n = 10 for prototypes I and II, respectively) were used. Each examination was followed by a standard colonoscopy for safety evaluation. The insertion length of the Aer-O-Scope was determined by fluoroscopy images. RESULTS: The colon was adequately clean in 25 procedures. Maximum insertion was achieved in 21 procedures (84%)--80% with prototype I (n = 15) and 90% with prototype II (n = 10). The time to maximum insertion averaged 8.9 +/- 4.4 min (10 +/- 4.6 and 6.6 +/- 2.9 min for prototypes I and II; P < 0.05), and the withdrawal time averaged 3.4 +/- 2.1 and 4.2 +/- 3.4 min, respectively. The driving pressures for prototypes I and II averaged 46.3 and 34.5 mbar, respectively. The follow-up conventional colonoscopy identified no mucosal tears or perforations. Minor mucosal petechiae were noted in 43% of the cases. No adverse events were noted up to 7 days after the procedure. CONCLUSIONS: The propulsion mechanism used in this novel self-propelled, self-navigating colonoscope was effective and safe in pigs.

Animals↗
PubMed2005

Sporadic adenomatous polyp regression with exisulind is effective but toxic: a randomised, double blind, placebo controlled, dose-response study.

BACKGROUND AND AIMS: A 12 month, multicentre, randomised, double blind, placebo controlled, phase 3, dose-response study was carried out. Exisulind inhibits tumour growth by induction of apoptosis. The aim of our study was to investigate if exisulind induces regression of sporadic colonic adenomas. PATIENTS AND METHODS: A 12 month multicentre randomised double blind placebo controlled phase 3 dose response study was carried out. At baseline colonoscopy, left sided polyps (3-10 mm) were tattooed, measured, and left in place. Subjects received exisulind 200 or 400 mg, or placebo daily. Follow up sigmoidoscopy was performed after six months, and removal of any remaining polyps at the 12 month colonoscopy. The primary efficacy variable was change in polyp size from baseline. RESULTS: A total of 281 patients were enrolled and randomised; 155 (55%) fulfilled the criteria for the intention to treat (ITT) analysis and 114 (41%) fulfilled the criteria for the efficacy evaluation analysis (patients who underwent the 12 month colonoscopy). The decrease in median polyp size was significantly greater (p=0.03) in patients who received exisulind 400 mg (-10 mm2) compared with those who received placebo (-4 mm2). Complete or partial response was significantly higher in the exisulind 400 mg group (54.6%) compared with the placebo group (30.2%), and disease progression was significantly lower (6.1% v 27.9%) (p=0.04 and 0.02, respectively). Increased liver enzymes (8.4%) and abdominal pain (14.7%) were also reported at a greater frequency in the exisulind 400 mg group. CONCLUSION: Exisulind caused significant regression of sporadic adenomatous polyps but was associated with more toxicity. This model of polyp regression, short in its term and involving a comparatively small patient sample size, may be the best available tool to assess a therapeutic regimen before launching into large preventive clinical studies.

Adenomatous Polyposis Coli↗
PubMed2001

Malignant melanoma: patterns of metastasis to the small bowel, reliability of imaging studies, and clinical relevance.

OBJECTIVES: The aims of this study were to determine the frequency of different patterns of melanoma metastases to small bowel on radiological examination, and to assess the reliability of the most commonly used radiological methods for detecting these lesions. METHODS: The records of cases archived as melanoma metastatic to the small bowel of the Armed Forces Institute of Pathology were reviewed. The clinical information, type of imaging procedure performed, and radiological features were analyzed and compared to the findings at surgery and at autopsy. RESULTS: A total of 32 patients had clinical and surgical data with pathological confirmation. Seven patients had metastasis involving the duodenum, 22 had jejunal involvement, and 11 had ileal involvement. Metastases were categorized as polypoid, cavitary, infiltrating, or exoenteric. The polypoid pattern was seen in 20 patients (63%), six of whom showed multiple polypoid lesions (>10), referred to as polyposis. The "target lesion," a discrete polypoid mass with a central ulceration, was observed in only three (9%) of the 32 patients. Eight patients (25%) demonstrated a cavitary pattern, a circumferential mass with inner marginal necrosis, and five (16%) showed an infiltrating pattern. One patient (3%) had an exoenteric lesion with a fistulous tract. The small bowel follow-through demonstrated 32 of 55 metastases (sensitivity 58%). Contrast-enhanced CT demonstrated 32 of 48 masses (sensitivity 66%). Of the six cases of malignant polyposis, none were identified using CT, and only two were diagnosed by small bowel follow-through. CONCLUSIONS: The polypoid pattern, equally distributed between the jejunum and ileum, is the most common manifestation of metastatic melanoma to the small bowel. The target lesion was infrequently seen in this series. Small bowel follow-through and conventional CT seem to be unreliable in demonstrating melanoma metastases to the small bowel.

Adult↗
PubMed2000

Should we colonoscope women with gynecologic cancer?

Retrospective analysis of the Surveillance Epidemiology and End Results (SEER) program database for the period 1974 through 1995 identified 101,734 white and African-American women, age > or = 25 yr, with prior cervical, endometrial, or ovarian cancer. Subsequent follow-up demonstrated no increased risk of colorectal cancer in women with cervical cancer. For endometrial cancer patients, increased risk of colorectal cancer was confined to women whose diagnosis of endometrial cancer was before age 50, but the increased risk was substantial in this group (RR 3.39; 95% CI 2.73-4.17). For ovarian cancer patients, increased risk for colorectal cancer was substantial for those diagnosed with ovarian cancer before age 50 (RR 3.67; 95% CI 2.74-4.80), and there was some increased risk for women diagnosed at ages 50-64 yr (RR 1.52; 95% CI 1.25-1.83).

Adult↗
PubMed1999

Variable pathologic interpretation of columnar lined esophagus by general pathologists in community practice.

BACKGROUND: Pathologic interpretation of biopsy specimens of columnar lined esophagus guides subsequent endoscopic surveillance and/or surgical intervention. The aim of this study was to evaluate pathologic interpretation of columnar lined esophagus by general pathologists in community practice. METHODS: Five histologic slides representing different types of columnar lined esophagus were submitted for review by 20 randomly selected general pathologists in community practice. There were three cases with intestinal metaplasia (one with no dysplasia, one with low-grade dysplasia, and one with high-grade dysplasia) and two cases of gastric metaplasia (one fundic-type and one cardia-type). RESULTS: High-grade dysplasia was identified as such by 30% of pathologists and was called invasive adenocarcinoma by 20%, low-grade dysplasia by 30%, and moderate dysplasia by the remaining 20%. Low-grade dysplasia was identified as such by 35% of pathologists and was called high-grade dysplasia by 20%, moderate dysplasia by 20%, and no dysplasia by 25%. Specialized columnar epithelium with no dysplasia was identified as such by 35%, called low-grade dysplasia by 35%, moderate dysplasia by 15%, indeterminate for dysplasia by 10%, and invasive adenocarcinoma by 5%. Gastric metaplasia without specialized columnar epithelium was identified as Barrett's esophagus in 38% of cases. CONCLUSIONS: Pathologic interpretation of columnar lined esophagus by community pathologists may be subject to marked interobserver variation. The term Barrett's esophagus is often used to describe columnar lined esophagus without goblet cells. Because this finding is not clearly associated with an increased risk of cancer, these data support recent suggestions that the term Barrett's esophagus be abandoned. Interpretations of both high-grade and low-grade dysplasia should be considered for review by experts in esophageal pathology.

Barrett Esophagus↗
PubMed1999

Accuracy of polyp detection by gastroenterologists and nurse endoscopists during flexible sigmoidoscopy: a randomized trial.

BACKGROUND & AIMS: The use of nurse endoscopists to perform flexible sigmoidoscopy is expanding, increasing the availability of colorectal cancer screening. However, the effectiveness of this practice has not been studied in randomized trials. The aim of this trial was to examine the miss rate of polyps, the depth of sigmoidoscope insertion, and the incidence of complications during flexible sigmoidoscopy performed by nurse endoscopists and by gastroenterologists. METHODS: Three hundred twenty-eight patients were randomized to undergo screening flexible sigmoidoscopy performed by a nurse endoscopist or by a gastroenterologist. Frequency of missed polyps was determined by repeat sigmoidoscopy, performed by a gastroenterologist blinded to the identity of the first endoscopist. Multiple logistic regression analysis identified characteristics associated with missed polyps. RESULTS: Gastroenterologists and nurse endoscopists had equivalent miss rates for adenomatous polyps (20% vs. 21%, respectively; P = 0.91). No complications occurred in any patient. Gastroenterologists inserted the sigmoidoscope further than nurse endoscopists (61 vs. 55 cm, respectively; P < 0.00001). Polyp location in the descending colon (odds ratio, 4.1; 95% confidence interval, 1.7-10.3) was highly associated with missed polyps. CONCLUSIONS: No differences in detection of adenomatous polyps or frequency of complications were found. These data suggest that experienced nurse endoscopists may perform screening flexible sigmoidoscopy as safely and as effectively as gastroenterologists.

Adult↗
PubMed1997

Use of the 25 mm flanged esophageal Z stent for malignant dysphagia: a prospective multicenter trial.

BACKGROUND: An initial multicenter study using a 21 mm flanged esophageal Z stent demonstrated excellent palliation but an 11% immediate complication rate at placement and a 27% migration rate at 1 month. This North American multicenter trial prospectively studied a 25 mm flanged Z stent to define its palliative ability and whether the increased diameter affected placement or migration problems. METHODS: Fifty patients who had esophageal Z stents at seven university or regional referral hospitals were prospectively studied. Indications for prosthesis placement, previous therapy, patient demographics, incidence of concomitant tracheoesophageal fistula, and degree of dysphagia were defined, as were procedural and subsequent stent-related problems, survival times, the ability to occlude a tracheoesophageal fistula, and subsequent degree of dysphagia. RESULTS: Twenty-four patients had infiltrating malignancy (16 exophytic and 10 extrinsic), 9 of whom had concomitant tracheoesophageal fistulas. Ten patients (20%) had misplaced stents requiring retrieval and replacement, 12 patients (24%) had subsequent stent-related problems including exsanguination (2), aspiration (3), tumor overgrowth (3), and postplacement migration (4) (8%). There was statistically significant improvement in prestent versus poststent dysphagia and two thirds of patients had complete occlusion of their tracheoesophageal fistula. CONCLUSIONS: Redesign of the esophageal Z stent has decreased the migration rate without increasing placement or subsequent erosion problems. Its efficacy appears comparable to the currently marketed Z stent for the palliation of malignant dysphagia and occlusion of tracheoesophageal fistula.

Aged↗
PubMed1997

Energy consumption in children with myelomeningocele: a comparison between reciprocating gait orthosis and hip-knee-ankle-foot orthosis ambulators.

This study compared the differences in energy efficiency (energy cost) in children with myelomeningocele ambulating with either reciprocating gait orthoses (RGOs) or hip-knee-ankle-foot orthoses (HKAFOs). There were 15 children who ambulated with RGOs and 11 children braced and ambulating in HKAFOs. Velocity was measured in m/s, energy consumption was measured in mL/kg/min, and energy cost (energy consumption/velocity) was measured in mL/kg/m. Children in HKAFOs had a significantly higher energy consumption rate than children in RGOs. However, children who swing through in a HKAFO have a significantly faster velocity than children who ambulate with the RGO using a reciprocating pattern. The increased energy cost in the RGO group is influenced by their slower velocity, just as the decreased energy cost in the HKAFO group is influenced by their increased velocity. Therefore it appears that children in HKAFOs are more energy efficient than children in RGOs.

Adolescent↗
PubMed1997

Subtotal colectomy in a patient with collagenous colitis associated with colonic carcinoma and systemic lupus erythematosus.

A case of colonic carcinoma is described in a 60-yr-old woman with the typical clinical and histopathologic features of collagenous colitis and systemic lupus erythematosus, who is doing well 24 months after undergoing a subtotal colectomy with Brooke ileostomy. Collagenous colitis has only rarely been previously reported in association with colonic carcinoma (n = 1 case) or systemic lupus erythematosus (n = 1 case). In addition, this case is the second report of symptomatic collagenous colitis refractory to medical therapy, treated successfully with surgery.

Adenocarcinoma↗
PubMed1996

The effect of environmental pH on the proton motive force of Helicobacter pylori.

BACKGROUND & AIMS: Responses of the proton motive force (the driving force for protons) in Helicobacter pylori to varying medium pH may explain gastric colonization. The aim of this study was to determine the effect of external pH (pHout) on the proton motive force, the sum of the pH gradient, and the potential difference across the bacterial membrane. METHODS: Intracellular pH (pHin) was measured by bis-carboxyethyl-carboxy fluorescein fluorescence and transmembrane potential difference (PD) by fluorescent quenching of 3,3'-dipropyl thiadicarbocyanine iodide at differing pHout and was correlated with survival. RESULTS: PD was -131 +/- 0.36 mV (n = 3), and pHin was about 8.4 at loading pHout 7.0. PD increased as pHout was increased from 4.0 to 8.0, giving a constant proton motive force of about -220 mV. Outside these limits, PD collapsed irreversibly to zero. Addition of 5 mmol/L urea to weak buffer at pH 3.0 or 3.5 prevented irreversible collapse of PD by elevation of pHout caused by NH3 production. Urea addition to weak buffer at pH 7.0 collapsed the PD as urease activity increased the pHout to about 8.4. Survival was also limited to this range of pHout. CONCLUSIONS: H. pylori survives over the range of pHout where it maintains a proton motive force. The effect of urease activity on pHout, while allowing gastric survival in acidic media, may limit survival in nonacidic media.

Ammonium Chloride↗
PubMed1987

Small bowel radiography: how, when, and why?

Since the advent of endoscopy for evaluating the upper and lower gastrointestinal (GI) tracts, it has become clear that only in the small bowel does barium radiography remain unchallenged. Regrettably, barium examination of the small bowel has traditionally been regarded by many radiologists as a study of minor importance. Small bowel follow-through techniques and enteroclysis methods differ in their diagnostic purpose, potential, and methods of performance. This review examines in detail the spectrum of barium examination techniques currently available for evaluating the small bowel. The benefits of enteroclysis in the majority of clinical situations requiring contrast examination of the small bowel are stressed. Radiologists play the crucial role in the diagnostic evaluation of the small bowel and should strive to refine and advance the accuracy of small bowel radiography.

Administration, Oral↗
PubMed1983

Intrahepatic cholestasis and sicca complex after thiabendazole. Report of a case and review of the literature.

Thiabendazole is a relatively safe and effective agent with a wide range of activity against nematodes infesting the gastrointestinal tract. A 55-yr-old man developed prolonged jaundice and sicca complex after a course of thiabendazole therapy. Endoscopic retrograde cholangiopancreatography demonstrated normal biliary tree and pancreatic ducts. Liver biopsy was consistent with a drug-induced intrahepatic cholestatic reaction. The patient recovered completely from his liver injury, but the sicca complex persisted 1 yr after the drug was given. The literature on thiabendazole-induced cholestasis and its association with sicca complex is reviewed.

Biopsy↗
PubMedDate not supplied

Remission of overt diabetes mellitus after removal of an oral epidermoid carcinoma.

This report describes a patient with an invasive epidermoid carcinoma of the tongue who presented with insulin-requiring diabetes mellitus. Fasting blood glucose was 379 mg/dl and 295 mg/dl on two successive days. The patient required 35 to 40 units of insulin per day for control. After removal of the carcinoma the insulin requirements decreased, and ultimately the insulin was stopped. One year after removal of the carcinoma, glucose and insulin levels were completely normal during an oral glucose tolerance test, demonstrating complete remission of overt diabetes mellitus.

Carcinoma, Squamous Cell↗
PubMedDate not supplied

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Diet↗