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Biomedical subjects

Simon Bar-Meir

Publications and source records attributed to Simon Bar-Meir.

At least 19 recordsLinked to original sources

Long-standing colonic inflammation is associated with a low prevalence of diverticuli in inflammatory bowel disease patients.

BACKGROUND: Diverticulosis is associated with high intracolonic pressure and a weakened bowel wall. Chronic colitis is characterized by liquid stools suggestive of low intracolonic pressure and a thickened bowel wall. Therefore, the aim of this study was to assess the prevalence of diverticulosis in colitis patients. METHODS: Colonoscopy results of patients with inflammatory bowel disease (IBD)-associated colitis older than 50 years were retrospectively evaluated and compared with those of patients who underwent screening colonoscopy. Only patients with biopsy-proven disease, disease duration of more than 5 years, and disease beyond the distal 20 cm were included. RESULTS: In all, 1037 patients were diagnosed by colonoscopy as suffering from IBD-associated colitis between 1987-2005. After exclusion of patients who did not meet the inclusion criteria the study population consisted of 314 IBD patients and 1023 age-matched control patients. A significantly higher percent of diverticuli was detected in the control group compared with the IBD group (15% versus 3.5%, P < 0.001). No significant difference in the prevalence of diverticuli was detected between the three subtypes of IBD patients (2% in ulcerative colitis versus 4.7% in Crohn's colitis versus 7.6% in indeterminant colitis). Neither disease duration nor the specific colonic segment involved had a significant influence on the prevalence of diverticulosis. CONCLUSIONS: Long-standing colonic inflammation in IBD patients is associated with a lower prevalence of diverticuli.

Colitis↗

Diverticulitis in the young patient--is it different ?

AIM: To prospectively study the incidence and the natural history of acute diverticulitis in young patients. METHODS: A total of 207 patients hospitalized at our hospital between January 2000 to February 2005 with the diagnosis of acute diverticulitis were included. Their demographic characteristics, medical history, physical, radiographic and endoscopic findings as well as therapy were recorded. Patients were followed every 6 mo for the first year and later annually. RESULTS: The mean patients' age was 61 (range 27-92) years. Twenty-five patients (12%) were younger than 45 years. Acute diverticulitis was significantly more prevalent among male in the young age group as compared to the older age group (19/25, 76% vs 61/182, 33%, respectively, P = 0.0001). Complications occurred more often in the young age group; 32% vs 13%, (P = 0.002). During follow-up, 6 patients (28%) remained asymptomatic in the young age group as compared to 87 patients (55%) in the older age group (P = 0.024). As a result, sigmoidectomies were performed twice as often in the young age group (38% vs 13%, P = 0.002). CONCLUSION: Diverticulitis in young patients has a male predominance, a more aggressive course with a higher rate of complications and a higher recurrence rate. An earlier surgical approach might be considered in young patients with acute diverticulitis.

Acute Disease↗

Simbionix simulator.

The GI Mentor (Simbionix, Lod, Israel) is a computer-based simulator used for training in endoscopy. It contains modules for training in hand-eye coordination, upper and lower gastrointestinal endoscopy, endoscopic retrograde cholangiopancreatography, and endoscopic ultrasonography. It provides experience in the steering and torque of the endoscope, suction, and inflation, a realistic view through the monitor, and a realistic force feedback when performing the procedure. Its advantages include its availability for training with no need for previous preparation and the constant interaction with the trainee. It is costly, however, and presently is suitable only for the initial steps of training.

Clinical Competence↗

Endoscopic ultrasound staging of rectal cancer: diagnostic value before and following chemoradiation.

BACKGROUND: Endoscopic ultrasound (EUS) has been shown to be a reliable tool for staging rectal cancer. Nevertheless, the accuracy of EUS after chemoradiation remains unclear; therefore the purpose of the present paper was to compare the accuracy of EUS staging for rectal cancer before and following chemoradiation. METHODS: Patients with rectal cancer undergoing EUS staging were stratified into two groups. Group I consisted of 66 patients who underwent surgery following EUS staging without preoperative chemoradiation. Group II consisted of 25 patients who had EUS evaluation following chemoradiation. The EUS staging was compared to surgical/pathological staging. RESULTS: The accuracy of the T staging for group I was 86% (57/66). Inaccurate staging was mainly associated with overstaging EUS T2 tumors. The accuracy of the N staging for group I was 71% (47/66). The accuracy of EUS for a composite T and N staging relevant to treatment decisions in group I was 91%. In group II, the accuracy of T and N staging was 72% (18/25) and 80% (20/25), respectively. Overstaging EUS T3 tumors accounted for most inaccurate staging. The EUS staging predicted post-chemoradiation T0N0 stage correctly in only 50% of cases. CONCLUSIONS: Preoperative staging of rectal cancer by EUS is a useful modality in determining the need for preoperative chemoradiation. The EUS T staging following chemoradiation appears to be less accurate. Detection of complete response may be insufficient for selecting patients for limited surgical intervention.

Adult↗

TNF-857 polymorphism in Israeli Jewish patients with inflammatory bowel disease.

Tumour necrosis factor (TNF)-alpha is an important pro-inflammatory cytokine that has been implicated in the pathogenesis of inflammatory bowel disease (IBD). The promoter TNF-857 C-->T single nucleotide polymorphism (SNP) is functional through the binding to the transcription factor octamer transcription factor-1 (OCT-1). In order to investigate the frequency of this SNP in Israeli Jewish IBD patients, we analysed a cohort of well-characterized patients, 153 with Crohn's disease (CD) and 78 with ulcerative colitis (UC) and 188 healthy controls individually matched for age, sex and ethnicity. Forty-one per cent of the patients were of Ashkenazi and 48% were of non-Ashkenazi background. The remaining 11% were of mixed Ashkenazi-non-Ashkenazi background. Patients and controls were genotyped for the TNF-857 SNP by Taqman technology. Stratification for the CARD15 Arg702Trp, Gly908Arg and Leu1007fsinsC mutations took place in 136 CD patients. Carrier frequency of TNF-857T between CD and controls (36% vs. 40%; P = 0.556; OR: 1.18, 95% CI 0.74-1.88), or between UC and controls (41% vs. 37%; P = 0.743; OR: 0.85, 95% CI 0.45-1.62) did not differ significantly. Neither did stratifying for the presence of at least one of the common CARD15 mutations result in a significant difference between CD and controls. No associations were found between TNF-857T and CD phenotype as defined by the Vienna classification, perianal disease or extra-intestinal disease irrespective of CARD15 carrier status. In conclusion, it appears that TNF-857 SNP does not contribute to susceptibility of IBD, neither does it define the phenotype of CD in Israeli Jewish IBD patients.

Adult↗

[Clinical and communication simulation workshop for fellows in gastroenterology: the trainees' perspective].

BACKGROUND: The continuing development in computer-based medical simulators provides an ideal platform for simulator-assisted training programs for medical trainees. Computer-based endoscopic simulators provide a virtual reality environment for training endoscopic procedures. This study illustrates the use of a comprehensive training model combining the use of endoscopic simulators with simulated (actor) patients (SP). AIM: To evaluate the effectiveness of a comprehensive simulation workshop from the trainee perspective. METHODS: Four case studies were developed with emphasis on communication skills. Three workshops with 10 fellows in each were conducted. During each workshop the trainees spent half of the time in SP case studies and the remaining half working with computerized endoscopic simulators with continuous guidance by an expert endoscopist. Questionnaires were completed by the fellows at the end of the workshop. RESULTS: Seventy percent of the fellows felt that the endoscopic simulator was close or very close to reality for gastroscopy and 63% for colonoscopy. Eighty eight percent thought the close guidance was important for the learning process with the simulator. Eighty percent felt that the case studies were an important learning experience for risk management. CONCLUSION: Further evaluation of multi-modality simulation workshops in gastroenterologist training is needed to identify how best to incorporate this form of instruction into training for gastroenterologists.

Computer-Assisted Instruction↗

Increasing the infliximab dose is beneficial in Crohn's disease patients who responded to a lower dose and relapsed.

BACKGROUND: Relapse after an initial response to infliximab therapy poses a problem for maintenance treatment. AIM: To assess the effects of increasing the infliximab dosage in Crohn's disease (CD) patients who initially responded but flared during maintenance therapy. METHODS: This was an observational study. Twelve CD patients with both inflammatory and fistulizing manifestations were included. All patients initially responded to 5 mg/kg of infliximab, relapsed during maintenance therapy, and were treated with 10 mg/kg. The Harvey-Bradshaw index, the fistula activity, and steroid use were assessed before and after treatment with the increased dose of infliximab. RESULTS: The mean Harvey-Bradshaw index score after flare-up during treatment with 5 mg/kg of infliximab was 13.5+/-3.7. Treatment with 10 mg/kg, in a mean of 3.3 infusions, decreased the activity score to a mean of 8.8+/-2.5. Two patients were weaned off prednisone, and a reduced dose was possible in the other steroid-treated patients. CONCLUSIONS: Increasing the infliximab dose may be beneficial in CD patients who initially responded to therapy, but relapsed during maintenance with the lower dosage.

Adult↗

Endosonographic evaluation of perianal fistulas and abscesses: comparison of two instruments and assessment of the role of hydrogen peroxide injection.

PURPOSE: The aims of this study were to compare the performance of a mechanical radial endosonoscope and an endorectal electronic probe and to evaluate the value of hydrogen peroxide (H(2)O(2)) injection in the diagnosis of perianal fistulas. PATIENTS AND METHODS: Sixty-one patients underwent clinical and endosonographic studies for suspected perianal fistulas or abscesses. Endosonography was performed using two instruments: a mechanical radial endosonoscope (Olympus GF-UM20) and an electronic endorectal probe (Hitachi EUP-R53). The patients were re-examined during and following H(2)O(2) injection using both systems. RESULTS: Thirty-seven fistulous tracts were visualized with the electronic endorectal probe versus only 9 with the mechanical radial endosonoscope. Four patients had anal stenosis, precluding the use of the larger electronic probe. Three fistulas were detected in these patients using the mechanical radial endosonoscope. H(2)O(2) injection was not feasible in 26 patients (43%). Visualization of 11 (31%) fistulas improved after administration of H(2)O(2). Six fistulous tracts not detected before H(2)O(2) administration were clearly visualized during injection and for several minutes thereafter. CONCLUSIONS: Work-up of perianal fistula should be preferably performed using the endorectal electronic probe. However, the mechanical radial endoscope is preferred in patients with anal stricture. H(2)O(2) injection should become an integral part of every sonographic study of perianal fistulas.

Abscess↗

A prospective study of the diagnostic accuracy of PillCam ESO esophageal capsule endoscopy versus conventional upper endoscopy in patients with chronic gastroesophageal reflux diseases.

INTRODUCTION: Endoscopy is commonly performed to evaluate for suspected or established esophageal diseases including gastroesophageal reflux disease (GERD) and its complications. The newly developed PillCam ESO Esophageal Capsule offers an alternative approach to visualize the esophagus and to evaluate patients with suspected esophageal disease. AIM: Compare the accuracy (specificity, sensitivity, positive predictive value [PPV], and negative predictive value [NPV]) of esophageal capsule endoscopy (ECE) compared with esophagogastroduodenoscopy (EGD) in evaluating patients with GERD. METHODS: A multicenter pivotal trial was conducted at seven sites. The PillCam ESO esophageal capsule is similar to the standard capsule endoscope used for the small bowel but acquires video images from both ends of the device at 2 frames/second/end. A total of 106 patients (93 GERD; 13 Barrett) underwent ECE followed by EGD. ECE videos were evaluated by an investigator blinded to EGD findings. A blinded adjudication committee reviewed all discrepant findings between ECE and EGD. RESULTS: Sixty-six of 106 patients had positive esophageal findings, ECE identified esophageal abnormalities in 61 (sensitivity, 92%; specificity, 95%). The per-protocol sensitivity, specificity, PPV, and NPV of ECE for Barrett esophagus were 97%, 99%, 97%, and 99%, respectively, and for esophagitis 89%, 99%, 97%, and 94%, respectively. ECE was preferred over EGD by all patients. There were no adverse events related to ECE. CONCLUSIONS: ECE is a convenient and sensitive method for visualization of esophageal mucosal pathology and may provide an effective method to evaluate patients for esophageal disease.

Endoscopy, Gastrointestinal↗

Somatostatin inhibits pro-inflammatory cytokine secretion from rat hepatic stellate cells.

BACKGROUND/AIMS: Activated hepatic stellate cells (HSCs) have been implicated in hepatic fibrosis. Somatostatin (SOM) has an immunomodulatory role. The aim of this study was to assess the secretion of pro-inflammatory cytokines by HSCs and to determine the effect of SOM on the secretion of these mediators. METHODS: Activated rat HSCs were evaluated for their secretion of IL-1beta, IL-8, and TNF-alpha using ELISA. RNA protection assay was used to determine cytokine mRNA levels. The expression of chemokine and cytokine mRNA and the secretion of these mediators were assessed following incubation with SOM or octreotide. RESULTS: HSCs spontaneously secreted IL-1beta, IL-8, and TNF-alpha. This secretion was augmented following stimulation by IL-1beta and TNF-alpha. SOM inhibited the spontaneous and TNF-alpha-induced secretion of IL-1beta, IL-8, and TNF-alpha and suppressed the expression of IL-1beta and TNF-alpha mRNA. Octreotide suppressed the secretion of IL-1beta and IL-8. CONCLUSIONS: These observations indicate that SOM exerts an inhibitory immunomodulatory effect on HSCs.

Animals↗

The familial Mediterranean fever (MEVF) gene as a modifier of Crohn's disease.

OBJECTIVES: Crohn's disease (CD) has been reported to be more frequent among non-Ashkenazi Jewish patients suffering from familial Mediterranean fever (FMF). Interestingly, functional similarities between the CD susceptibility gene (NOD2/CARD15) and the FMF gene (MEFV) have been described: both belong to the death domain containing protein family, important in the regulation of apoptosis, cytokine processing and inflammation. AIMS: To investigate the prevalence of MEFV mutations in Jewish non-Ashkenazi CD patients and its putative effect on CD presentation. METHODS: Germline DNA of 105 Israeli CD patients of non-Ashkenazi and mixed Ashkenazi-non-Ashkenazi ethnic background was analyzed for three most common MEFV mutations: M694V, V726A, and E148Q. Five patients (4.7%) with a clinical diagnosis of FMF were included. Data obtained from each patient included: age of onset, disease location, and behavior, the presence of extraintestinal manifestations of CD and therapeutic regimens. RESULTS: The overall prevalence of mutation carriers among non-FMF-CD patients was 13% (13/100). A stricturing disease pattern was observed in 56% (10/18) of all carriers, FMF-CD, and non-FMF-CD patients, and in 25% (22/87) of noncarriers (OR: 3.7, 95% CI: 1.3-10.5, p= 0.015). The prevalence of fistulas was comparable in both groups. Extraintestinal manifestations were significantly more frequent among carriers than noncarriers (65%vs 32%, OR 3.9, 95% CI = 1.3-11.5, p= 0.015). No differences were observed in disease location and disease severity. CONCLUSIONS: MEFV mutations are not associated with CD susceptibility, yet the presence of these mutations appears to be associated with a stricturing disease pattern and extraintestinal disease manifestations of CD.

Adult↗

Allicin inhibits spontaneous and TNF-alpha induced secretion of proinflammatory cytokines and chemokines from intestinal epithelial cells.

BACKGROUND & AIMS: Allicin, the active substance of fresh crushed garlic has different biological activities and was implicated as an anti-inflammatory agent. Epithelial cells have an important role in intestinal inflammation. The aim of this study was to assess the immunomodulatory effect of allicin on intestinal epithelial cells. METHODS: The spontaneous and TNF-alpha-stimulated secretion of IL-1beta, IL-8, IP-10 and MIG from HT-29 and Caco-2 cells was tested with, or without pretreatment with allicin. Cytokine secretion was assessed using ELISA and expression of mRNA was determined by an RNA protection assay. RESULTS: Allicin markedly inhibited the spontaneous and TNF-alpha -induced secretion of IL-1beta, IL-8, IP-10 and MIG from the two different cell lines in a dose-dependent manner and suppressed the expression of IL-8 and IL-1beta mRNA levels. In addition, allicin suppressed the degradation of IkappaB. No effect on cell viability was noted. CONCLUSIONS: These observations indicate that allicin exerts an inhibitory immunomodulatory effect on intestinal epithelial cells and suggest that allicin may have the potential to attenuate intestinal inflammation.

Anti-Infective Agents↗

Colorectal cancer screening in patients presenting with an inguinal hernia: is it necessary?

BACKGROUND: It has been suggested that patients presenting with an inguinal hernia have an increased risk for colorectal cancer. Therefore, surgeons frequently request screening for colorectal cancer before surgery. The aim of this study was to assess the frequency of premalignant and malignant colonic lesions in a group of patients with an inguinal hernia, and to compare this with a control group of subjects undergoing screening colonoscopy. METHODS: In a case-control study, 243 patients with an inguinal hernia and no history of colonic neoplasia or symptoms suggestive of colorectal cancer underwent perioperative colonoscopy. The patients were stratified into two age groups: less than 50 years old (Group I) and more than 50 years old (Group II). The colonoscopic findings were compared with findings in 534 asymptomatic control patients who underwent screening colonoscopy. RESULTS: The mean age of patients (n=64) and control subjects (n=200) in Group I was similar, at 44 (3) years. The mean age of the patients (n=179) and control subjects (n=334) in Group II was, respectively, 70 (9) years and 64 (7) years (p<0.001). In Group I, no colorectal cancer was found in patients with inguinal hernia, and only one colorectal cancer was found among control subjects (p=0.571). In Group II, a diagnosis of colorectal cancer was made in 7 patients (4%) with inguinal hernia as compared with 10 patients (3%) among the control subjects (p=0.769). In both groups, the size and the histopathologic type of the polyps were not significantly different. CONCLUSIONS: In otherwise asymptomatic patients, the presence of inguinal hernia is not associated with an increased risk for colorectal cancer. Therefore, the presence of an inguinal hernia alone does not justify screening colonoscopy before herniorrhaphy.

Adult↗

Second capsule endoscopy for patients with severe iron deficiency anemia.

BACKGROUND: Patients with iron deficiency anemia are subjected to multiple endoscopic and radiologic examinations of the GI tract. If negative, some of the examinations are repeated, occasionally with positive findings. The diagnostic yield of a second capsule endoscopy in such patients is unknown. The aim of the current study was to assess the diagnostic yield of a second capsule endoscopy in patients with significant iron deficiency anemia and a previous negative evaluation. METHODS: Twenty patients with iron deficiency anemia (Hb < 10 g/dL) were enrolled. All had at least one normal evaluation of the GI tract, including capsule endoscopy. A second capsule endoscopy examination was offered to all patients. RESULTS: The time between the first and the second capsule endoscopy ranged from 2 months to 1 year. Depending on the nature of an abnormality and its relevance to blood loss, the findings were classified as positive, suspicious, clinically irrelevant, or negative. In 7 patients, the second capsule endoscopy disclosed findings that were classified as either positive or suspicious findings, including arteriovenous malformations (2), flat polypoid lesion (1), edematous inflamed mucosa (1), erosions (1), and hemorrhagic gastritis (1). Lesions were located in the small intestine (5), the stomach (1), and the cecum (1). Based on the findings of the second capsule endoscopy, therapy was changed in two patients (10%). CONCLUSIONS: A second capsule endoscopy should be considered for patients with severe iron deficiency anemia and negative initial evaluation.

Adult↗

Association between mutations in the CARD15 (NOD2) gene and Crohn's disease in Israeli Jewish patients.

Ulcerative colitis (UC) and Crohn's disease (CD) are heterogeneous disorders characterized by chronic intestinal inflammation. Genetic predisposition is a major risk factor in both diseases. The CARD15 (NOD2) gene has been implied as a candidate gene in the pathogenesis CD. Our aim was to delineate the frequency of three missense and one frameshift variant of CARD15 in Israeli Jewish CD and UC patients. DNA was extracted from blood samples from 238 unrelated inflammatory bowel disease (IBD) patients, 68 with UC and 170 with CD. The DNA was genotyped for two missense mutations, R675W and G881R, and one frameshift mutation, 980FS981X. Mutations in CARD15 were observed with significantly greater frequency in CD patients (46/170, 27%) than in UC patients (7/68, 10%) (P = 0.005). Homozygous and compound heterozygous carriers were restricted to seven (4%) patients with CD as compared to none of the UC patients (P = 0.01). Similar rates in Ashkenazi and non-Ashkenazi Jewish patients were observed. Age-of-onset of disease was lower in Ashkenazi mutation carriers as compared to non-carriers of Ashkenazi origin (18.7 +/- 8.6 years vs. 25.8 +/- 13.4 years, respectively, P = 0.03). No other phenotypic characteristics could distinguish mutation carriers from non-carriers. We conclude that germline mutations in the CARD15 gene are more frequently found in CD than UC patients and appear to predict an earlier age-of-onset in Ashkenazi Jewish patients. No association could be demonstrated between CARD15 mutations and specific disease course or behavior.

Adult↗

Genetic analysis of familial colorectal cancer in Israeli Arabs.

Colorectal cancers (CRC) among Israeli Arabs differ from those diagnosed in Jewish Israeli individuals in two manners: an earlier age of occurrence and a low frequency. These differences are unaccounted for and thus prompted us to perform genetic analysis in Israeli Arab CRC patients. Analysis included the major Hereditary non-polyposis colorectal cancer (HNPCC) genes and the APC I1307K mutation (MIM# 175100.0029). Twenty-five patients and 25 relatives from 24 unrelated families were clinically classified according to personal and familial cancer history. If MSI (microsatellite instability) was displayed in tumor tissue, patients underwent mutation analysis of the MSH2 and MLH1 genes using DGGE (denaturing gradient gel electrophoresis) and sequencing. MSI was detected in 9/21 of the tumors tested (43%). Two novel missense mutations were diagnosed among 11 fully analyzed patients: a change of A to G at position 380 in MSH2 (N127S), and a D601G mutation in MLH1. The I1307K mutation was detected in 8 families (8/24, 33.3%). This is the first report of genetic analysis in familial CRC associated genes among Israeli Arabs. We suggest that the I1307K mutation may contribute to CRC in Israeli Arabs and that inactivating mutations of MSH2 and MLH1 may not be a major cause for early onset CRC.

Adaptor Proteins, Signal Transducing↗

Budesonide foam vs. hydrocortisone acetate foam in the treatment of active ulcerative proctosigmoiditis.

INTRODUCTION: Rectal administration of corticosteroids is advocated in patients with proctosigmoiditis who have failed therapy with mesalamine enema. Foam offers patients better tolerability than an enema. In this study the efficacy and adverse effects of a new budesonide foam are compared with the presently available hydrocortisone foam. METHODS: Two hundred fifty-one patients with proctosigmoiditis were randomly assigned to receive either budesonide foam or hydrocortisone foam for eight weeks. RESULTS: Remission rates were comparable in the budesonide and hydrocortisone groups, 53 and 52 percent, respectively. The mean disease activity index for the two groups decreased to a similar extent, from 7.2 +/- 1.9 and 7 +/- 2 to 3.6 +/- 3.1 and 3.9 +/- 3.4 in the budesonide and hydrocortisone groups, respectively. In a subgroup of patients who had not responded to rectal administration of mesalamine, 23 of 44 (52 percent) patients who received budesonide responded favorably to the foam, as compared with 14 of 38 (37 percent) patients who received hydrocortisone (P = not significant). Low plasma cortisol occurred in 3 percent of the budesonide group and in none of the hydrocortisone patients. CONCLUSIONS: This trial demonstrates a similar efficacy and safety of the two foams in patients with proctosigmoiditis.

Administration, Rectal↗