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Papers by Marshall Bedine

Gastroenterology, May 1, 2023

Gastroenterology, May 1, 2019

Gastroenterology, May 1, 2018

Background: Colonic biofilms are polymicrobial bacterial aggregates that invade the inner mucus l... more Background: Colonic biofilms are polymicrobial bacterial aggregates that invade the inner mucus layer of the colon and interact directly with the colonic epithelium. Biofilms were previously shown to be a feature of colorectal cancer, particularly in tumors proximal to the hepatic flexure, where biofilms were present on >90% of tumors. Biofilms were also associated with procarcinogenic inflammatory changes even in healthy controls. However, a limited number of healthy individuals have been screened for biofilms, and factors influencing biofilm formation and/or the ability to detect biofilms remain unclear. Here we present preliminary biofilm epidemiology data from an ongoing screening colonoscopy cohort of 2,000 healthy individuals. Methods: From August 2016 through October 2017, 774 patients were enrolled at three endoscopy sites in the US. Six biopsies (3 proximal and 3 distal) per patient were fixed in Carnoy's for bacterial biofilm detection using fluorescence in situ hybridization with the universal bacterial probe EUB338. To date, 834 biopsies from 139 patients have been screened in a blinded, randomized manner by two independent screeners. Patients were defined as biofilm positive if at least one biopsy contained invasive bacterial aggregates spanning a length of >200 µm within 1 µm proximity of the colonic epithelium and with a density of 2x10^9 bacteria in a 5 µm-thick tissue section. Results: Fourteen of 139 patients (10%) were biofilm positive. Four of these patients had biofilms on both distal and proximal biopsies, 6 patients had biofilms only on their distal colon, and 4 had biofilms only on their proximal colon. Biofilm-positive and biofilm-negative patients did not significantly differ with respect to history of polyps (50% vs. 42%, p = 0.232 Fisher's exact test) or presence of polyps at the current colonoscopy (43% vs. 39%, p = 0.614 Fisher's exact test). These data only include premalignant lesions; hyperplastic polyps were excluded. Finally, preliminary data suggests that several factors may negatively influence the ability to detect biofilms, including the addition of magnesium citrate to a bowel prep consisting of both polyethylene glycol (Miralax R) and bisacodyl (Dulcolax R), and taking bowel preps within 12 h of a colonoscopy (also known as a "split prep"). Conclusions: Our preliminary data suggest that biofilms in healthy hosts do not differ with respect to colon location, in contrast to the overwhelming prevalence of biofilms on proximal tumors compared to distal tumors. Additionally, the impact of the timing and type of bowel prep on biofilm detection suggests that biofilms reassemble within 12-24 h of clearance via bowel preps. Future efforts will continue to monitor polyp formation and biofilm status in addition to examining the impact of dietary and other environmental factors on biofilm formation.

PubMed, 1990

Colorectal carcinoma is the second leading cause of cancer death in the U.S. The risk for colon c... more Colorectal carcinoma is the second leading cause of cancer death in the U.S. The risk for colon carcinoma increases after the age of 40 years. Because there is a very significant familial incidence of colorectal carcinoma, this is a major group of individuals who should be screened. The vast majority of colorectal carcinomas are associated with adenomatous polyps of the large intestine. Colonoscopy is the best procedure available to evaluate those at risk; the double-contrast barium enema and flexible sigmoidoscopy also play a significant role in diagnosis. Screening for occult blood in the stool is presently the best tool to evaluate groups for potential colorectal lesions. Although there are still significant problems with occult blood testing, it can account for a definite decrease in morbidity and mortality from colorectal carcinoma.

Comprehensive Therapy, Mar 1, 1999

Colorectal carcinoma is a leading cause of death in the United States. Risk factors include genet... more Colorectal carcinoma is a leading cause of death in the United States. Risk factors include genetic predispotion, diet, obesity, and inflammatory bowel disease. Early detection and chemoprevention can lead to a lower death rate. Future developments will include sensitive and specific larEe-scale screening. Colorectal carcinoma continues to be the second leading cause of cancer death in the United States {second to lung cancer}. In 1996 there were approximately 140,000 new cases of colorectal carcinoma diagnosed in the United States, with more than 55,000 deaths. The lifetime risk for the development of colorectal carcinoma is 6% for both men and women. Mortality figures are also equal. Although the U.S. incidence of colorectal cancer has increased slightly since 1973, there is a marked increase in the incidence in nonwhite and especially in African-American men. Total mortality has decreased, but has increased in African-Americans. Most colorectal carcinomas begin as asymptomatic tubular adenomas. Screening techniques are designed to detect and remove polyps, when small, to prevent the development of cancer. Risk for development of colorectal carcinoma increases with age, beginning at age 40 and rising rapidly after age 50. The distribution of colorectal carcinomas has changed so that only 50% are found in the rectum and sigmoid. This shift has implications for the type and cost of screening the population. RISK FACTORS AND CHEMOPREVENTION There are large differences in the incidence of colorectal carcinoma between the developed countries of the Western World and Asia, South America, and Africa. The role of environmental factors is suggested by evidence that Japanese immigrants to the United States develop higher rates of colorectal carcinoma with time and with changes toward a more Western diet. Similar changes have been noted among Israeli Jews who migrated from low-risk areas such as Yemen or North Africa. The rates of these groups eventually rise to the levels of the native populations. Diets with high fat intake (both saturated and unsaturated fat) may predispose to the develop-REPRINTS

Journal of Laparoendoscopic & Advanced Surgical Techniques, Aug 1, 2003

Obesity is increasing at an alarming rate. Approximately 25% of adult women and 20% of adult men ... more Obesity is increasing at an alarming rate. Approximately 25% of adult women and 20% of adult men in the United States are obese. Obesity is increasing even more rapidly in children. The incidence of type 2 diabetes mellitus, hypertension, dyslipidemia, and liver disease is significantly increased in obese persons. Traditional methods of diet, exercise, drugs, and behavior modification are unsuccessful in the treatment of patients who are morbidly obese and have a body mass index of 40 kg/m(2) or a body mass index of 35 kg/m(2) with comorbidity. Multiple surgical alternatives to the traditional treatments are available and have been successful. Considerable weight loss may be achieved and maintained. Each procedure is associated with a variety of side effects and complications. The selection of patients for bariatric surgery requires a careful evaluation of their medical condition in addition to multiple psychological and social factors. Postoperative care entails careful medical follow-up and long-term support. Patients may have a difficult time adjusting to their new ability to eat normally.

Gastroenterology, May 1, 2000

Digestive Diseases and Sciences, Feb 16, 2007

The Beckman Coulter DxN VERIS System is a fully automated, random access, closed molecular diagno... more The Beckman Coulter DxN VERIS System is a fully automated, random access, closed molecular diagnostic instrument for viral load quantification of hepatitis B virus (HBV). The purpose of this study was to compare the performance of the VERIS HBV Assay (Beckman Coulter DxN Veris HBV kit, U.S.A.) with our routine system (Artus HBV Qiagen kit, Germany) in clinical samples. A total of 67 HBV plasma samples from Kocaeli city, with the HBV DNA levels ranging from negative to >106 IU/ml, were analyzed by both using Qiagen kit and fully automated VERIS instrument that incorporates the extraction, purification, quantification, and results interpretation of infectious disease nucleic acid targets. For assay analysis, Bland Altman Data Plotting and Passing-Bablok regression analysis methods were used. According to the Bland Altman Plot (Veris combined Qiagen Log IU/ml), the specificity resulted 95% LoA (Cl 95% = −1.55-0.61), correlation 0.97 with standard deviation (SD) 0.55 and a mean SD = −0.47.HBV Passing-Bablok regression analysis indicates that Veris combined = −1.179 + 1.153 Qiagen Log IU/ml with correlation 0.97. The Veris DxN HBV system exhibited high sensitivity, specifity, linearity and reproducibility. In addition to that characteristics, being low cost and easy to use, make this system new solution for the detection of HBV infection.

The Western journal of medicine, 1977