Isoorientin attenuates benzo[a]pyrene-induced colonic injury and gut microbiota disorders in mice.

Benzo[a]pyrene (BaP, most toxic polycyclic aromatic hydrocarbon) is a global food-borne pollutant, and is associated with many diseases and gut microbiota disorders. The present study was designed to investigate the protective effects of isoorientin (ISO), a flavonoid compound in the human diet, on BaP-induced colonic damage and gut microbial disorders in mice. ISO was administered orally to mice at doses of 20 mg/kg body weight before BaP challenge (oral administration, 50 mg/kg body weight). The results revealed that ISO suppressed the BaP-induced reduction of body weight in mice, and it also prevented colonic damage, as evidenced by the increase in colon total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) activities, and the decrease in colon malonaldehyde (MDA) and hydrogen peroxide (H2O2) levels, compared to BaP-treated mice. Meanwhile, we used 16S rRNA gene sequencing to investigate the impact of BaP with or without ISO on the colon contents associated bacteria in mice. ISO could relieve the BaP-induced change in the abundance of gut microbiota, especially the genera of Feacalibaculum, Lactobacillus, Acinetobacter, Desulfovibrio and Alistipes. And ISO ameliorated BaP-induced microbiota metabolic disturbance, especially the metabolic pathways of LPS and sulphur compounds. In conclusion, our findings indicated that ISO could be of significant advantage in suppressing the colonic injury and the gut microbiota disorder induced by BaP.

Consenso mexicano sobre el diagnóstico y tratamiento de la enfermedad diverticular del colon / The Mexican consensus on the diagnosis and treatment of diverticular disease of the colon

Desde la publicación en 2008 de las guías de diagnóstico y tratamiento de la enfermedad diverticular del colon de la Asociación Mexicana de Gastroenterología ha habido avances significativos en el conocimiento de esta enfermedad. Se realizó una revisión sistemática de la literatura en PubMed de enero de 2008 a julio de 2018 con el fin de revisar y actualizar las guías 2008 y proporcionar nuevas recomendaciones basadas en la evidencia. Se incluyeron todas las publicaciones en español e inglés, de alta calidad. Se redactaron los enunciados, que fueron votados utilizando el método Delphi. Se estableció la calidad de la evidencia y la fuerza de las recomendaciones según el sistema GRADE para cada enunciado. Cuarenta y tres enunciados fueron finalmente votados y calificados. Se informan nuevos datos sobre definición, clasificación, epidemiología, fisiopatología y factores de riesgo. Se revisó con especial énfasis la utilidad de la tomografía computarizada y de la colonoscopia, así como los métodos endoscópicos para el control de la hemorragia. Se discutió sobre el tratamiento ambulatorio de la diverticulitis no complicada, el papel de la rifaximina y la mesalazina, en el manejo de la diverticulitis aguda complicada tanto en sus alternativas mínimamente invasivas hasta las opciones quirúrgicas con énfasis en sus indicaciones, limitaciones y contraindicaciones. Los nuevos enunciados proporcionan directrices basadas en la evidencia actualizada. Se presentan la discusión, el grado y la fuerza de la recomendación de cada uno de ellos.

Protective properties of combined fungal polysaccharides from Cordyceps sinensis and Ganoderma atrum on colon immune dysfunction.

In vivo an ecological network of polysaccharides utilization by gut microbiota is not only an intense competition but also an impressive cooperation pattern. The present study evaluated the in vivo protective effect of combined fungal polysaccharides (CFP) from Cordyceps sinensis and Ganoderma atrum on colon immune dysfunction, induced by 150mg/kg cyclophosphamide (CP). The results showed that C. sinensis polysaccharides (CSP) significantly promoted microbial-derived butyrate to improve histone h3 acetylation mediating regulatory T (Treg) cell specific Foxp3, as well as significantly restored CP-induced elevation of interleukin (IL)-17 and IL-21. Additionally, G. atrum polysaccharides (PSG) significantly down-regulated MyD88, as well as significantly increased IL-10 and TGF-ß3. Furthermore, CFP balanced the disequilibrium of cytokines secretion and Foxp3/RORγt ratio related Treg/T helper 17 (Th17) balance, as well as down-regulated the TLR-mediated inflammatory signaling pathway and promoted secretory immunoglobulin A (sIgA) secretion to suppress colonic inflammation. Therefore, our results typically contribute to understand the in vivo immunoregulatory function of fungal polysaccharides compounds, involving microbial-associated inflammatory signals and specific metabolic products.

In Silico and in Vitro Screening for P-Glycoprotein Interaction with Tenofovir, Darunavir, and Dapivirine: An Antiretroviral Drug Combination for Topical Prevention of Colorectal HIV Transmission.

The aim of the study was to use in silico and in vitro techniques to evaluate whether a triple formulation of antiretroviral drugs (tenofovir, darunavir, and dapivirine) interacted with P-glycoprotein (P-gp) or exhibited any other permeability-altering drug-drug interactions in the colorectal mucosa. Potential drug interactions with P-gp were screened initially using molecular docking, followed by molecular dynamics simulations to analyze the identified drug-transporter interaction more mechanistically. The transport of tenofovir, darunavir, and dapivirine was investigated in the Caco-2 cell models and colorectal tissue, and their apparent permeability coefficient (Papp), efflux ratio (ER), and the effect of transporter inhibitors were evaluated. In silico, dapivirine and darunavir showed strong affinity for P-gp with similar free energy of binding; dapivirine exhibiting a ΔGPB value -38.24 kcal/mol, darunavir a ΔGPB value -36.84 kcal/mol. The rank order of permeability of the compounds in vitro was tenofovir < darunavir < dapivirine. The Papp for tenofovir in Caco-2 cell monolayers was 0.10 ± 0.02 × 10-6 cm/s, ER = 1. For dapivirine, Papp was 32.2 ± 3.7 × 10-6 cm/s, but the ER = 1.3 was lower than anticipated based on the in silico findings. Neither tenofovir nor dapivirine transport was influenced by P-gp inhibitors. The absorptive permeability of darunavir (Papp = 6.4 ± 0.9 × 10-6 cm/s) was concentration dependent with ER = 6.3, which was reduced by verapamil to 1.2. Administration of the drugs in combination did not alter their permeability compared to administration as single agents. In conclusion, in silico modeling, cell culture, and tissue-based assays showed that tenofovir does not interact with P-gp and is poorly permeable, consistent with a paracellular transport mechanism. In silico modeling predicted that darunavir and dapivirine were P-gp substrates, but only darunavir showed P-gp-dependent permeability in the biological models, illustrating that in silico modeling requires experimental validation. When administered in combination, the disposition of the proposed triple-therapy antiretroviral drugs in the colorectal mucosa will depend on their distinctly different permeability, but was not interdependent.

Melatonin alleviates brain and peripheral tissue edema in a neonatal rat model of hypoxic-ischemic brain damage: the involvement of edema related proteins.

BACKGROUND: Previous studies have indicated edema may be involved in the pathophysiology following hypoxic-ischemic encephalopathy (HIE), and melatonin may exhibit neuro-protection against brain insults. However, little is known regarding the mechanisms that involve the protective effects of melatonin in the brain and peripheral tissues after HIE. The present study aimed to examine the effects of melatonin on multiple organs, and the expression of edema related proteins in a neonatal rat model of hypoxic-ischemic brain damage (HIBD). METHODS: One hundred ninety-two neonatal rats were randomly divided into three subgroups that underwent a sham surgery or HIBD. After the HIBD or sham-injury, the rats received an intraperitoneal injection of melatonin or an equal volume vehicle, respectively. We investigated the effects of melatonin on brain, kidney, and colon edema via histological examination and the expression of edema related proteins, including AQP-4, ZO-1 and occludin, via qPCR and western blot. RESULTS: Our data indicated (1) Melatonin reduced the histological injury in the brain and peripheral organs induced by HIBD as assessed via H-E staining and transmission electron microscopy. (2) Melatonin alleviated the HIBD-induced cerebral edema characterized by increased brain water content. (3) HIBD induced significant changes of edema related proteins, such as AQP-4, ZO-1 and occludin, and these changes were partially reversed by melatonin treatment. CONCLUSIONS: These findings provide substantial evidence that melatonin treatment has protective effects on the brain and peripheral organs after HIBD, and the edema related proteins, AQP4, ZO-1, and occludin, may indirectly contribute tothe mechanism of the edema protection by melatonin.

Use of a Barbed Knotless Suture for Laparoscopic Ablation of the Nephrosplenic Space in 8 Horses.

OBJECTIVE: To evaluate use of a knotless suture for laparoscopic closure of the equine nephrosplenic space. STUDY DESIGN: Experimental in vivo study. ANIMALS: Normal horses without previous history of abdominal surgery (n=8). METHODS: The nephrosplenic space was closed under laparoscopic visualization using a unidirectional, barbed 0 metric absorbable suture (copolymer of glycolic acid and trimethylene carbonate). Intracorporeal suturing of the nephrosplenic space was performed in a cranial-to-caudal direction in a simple continuous fashion. Repeat evaluation was performed laparoscopically in 2 horses and by necropsy in 6 horses. The length of closure was measured and nature of the healed tissue was evaluate grossly. RESULTS: Total surgery time was 65-167 minutes (mean ± SD, 89.6 ± 22.6). Suturing time was 30-65 minutes (40.4 ± 16.3). Second laparoscopy in 2 horses was performed at days 198 and 227. Necropsy was performed at day 69-229 postoperatively (132.7 ± 63.0) in 6 horses. The closure measured 12-14 cm in length (13 ± 1) and consisted of mature fibrous tissue bridging the splenic capsule and the nephrosplenic ligament. No residual suture material was identified grossly in any horses. The procedure was easily performed; extracorporeal suture management to hold it taut was unnecessary since the barbs had excellent purchase in the apposed tissues, and intracorporeal knot tying was not required. CONCLUSION: The barbed knotless suture appears to be a valid alternative to facilitate laparoscopic closure of the nephrosplenic space in normal horses; however, further work is necessary to investigate its suitability in clinically affected horses.

Comparison of Efficacy of Prophylactic Endoscopic Therapies for Postpolypectomy Bleeding in the Colorectum: A Systematic Review and Network Meta-Analysis.

OBJECTIVES: Although various endoscopic therapies have been suggested for preventing bleeding after colorectal polypectomy, the optimal therapy has yet to be fully clarified. We assessed the comparative efficacy of prophylactic therapies for postpolypectomy bleeding through a network meta-analysis combining direct and indirect comparisons. METHODS: We searched for all relevant randomized controlled trials published up until January 2016 examining the effects of prophylactic therapy for bleeding after colorectal polypectomy. The types of prophylactic therapy were classified as mechanical therapy, epinephrine-saline injection therapy, coagulation therapy, combined therapy, or no prophylactic therapy. Combined therapy was defined as a combination of two or more types of therapy including mechanical therapy, epinephrine-saline injection therapy, and coagulation therapy. We performed a Bayesian network meta-analysis for all prophylactic therapies. RESULTS: Fifteen studies with 3,462 patients were included in the meta-analysis. Compared with no prophylactic therapy, both epinephrine-saline injection and mechanical therapy showed superiority for preventing early postpolypectomy bleeding with a moderate quality of evidence (injection therapy, risk ratio (RR; 95% credible interval (CrI))=0.32 (0.11-0.67); mechanical therapy, RR (95% CrI)=0.13 (0.03-0.37)). Combined therapy did not show a statistically significant difference for decreasing the risk of early bleeding compared with injection or mechanical therapies, respectively (combined vs. injection therapy: RR (95% CrI)=0.35 (0.10-1.00); combined vs. mechanical therapy: RR (95% CrI)=0.88 (0.23-3.00)). In cases of delayed bleeding, no type of prophylactic therapy decreased the risk of bleeding compared with no prophylactic therapy. CONCLUSIONS: Either mechanical therapy or injection therapy reduced the risk of early postpolypectomy bleeding. As for delayed bleeding, none of the prophylactic therapies was associated with a lower risk of bleeding compared with no prophylactic therapy.

Colonoscopia óptica y colonoscopia virtual. El papel de cada una hoy / Optical colonoscopy and virtual colonoscopy: The current role of each technique

La importancia de la colonoscopia óptica o convencional para diagnosticar enfermedades del colon es indiscutible. Es la exploración de referencia con la que cualquiera debe validarse. Además de inspeccionar directamente la mucosa del colon, permite hacer biopsias y técnicas para tratar y prevenir el cáncer colorrectal. La colonoscopia virtual, o colonografía-TC, se ha validado en estudios multicéntricos y es una técnica tan sensible como la colonoscopia convencional para diagnosticar pólipos y cáncer de colon. Es la única alternativa válida actual a la colonoscopia convencional. Su papel en el paciente con riesgo medio o alto de cáncer colorrectal se define día a día a medida que los equipos multidisciplinarios ganan experiencia. El objetivo de este trabajo es discutir la utilidad de la colonoscopia virtual en diferentes situaciones clínicas, destacando aquellas con evidencia científica suficiente, y discutir las controversias de su posible uso en el cribado poblacional (AU)

The importance of optical or conventional colonoscopy in diagnosing colon disease is undisputed. In this context, optical colonoscopy is the gold standard against which other techniques must be validated. Apart from enabling direct inspection of the colonic mucosa, optical colonoscopy enables biopsies and techniques to treat and prevent colorectal cancer. Virtual colonoscopy or CT colonography has been validated in multicenter studies; virtual colonoscopy is as sensitive as optical colonoscopy for the detection of polyps and colon cancer. It is currently the only valid alternative to optical colonoscopy. Its role in patients with medium or high risk of colon cancer is in the process of being defined as multidisciplinary teams gain experience. This article aims to discuss the usefulness of virtual colonoscopy in different clinical situations, emphasizing the situations in which there is enough scientific evidence, and to discuss the controversies surrounding its possible use for population-based screening (AU)

Development and validation of an algorithm for classifying colonoscopy indication.

BACKGROUND: Accurate determination of colonoscopy indication is required for managing clinical programs and performing research; however, existing algorithms that use available electronic databases (eg, diagnostic and procedure codes) have yielded limited accuracy. OBJECTIVE: To develop and validate an algorithm for classifying colonoscopy indication that uses comprehensive electronic medical data sources. DESIGN: We developed an algorithm for classifying colonoscopy indication by using commonly available electronic diagnostic, pathology, cancer, and laboratory test databases and validated its performance characteristics in comparison with a comprehensive review of patient medical records. We also evaluated the influence of each data source on the algorithm's performance characteristics. SETTING: Kaiser Permanente Northern California healthcare system. PATIENTS: A total of 300 patients who underwent colonoscopy between 2007 and 2010. INTERVENTIONS: Colonoscopy. MAIN OUTCOME MEASUREMENTS: Algorithm's sensitivity, specificity, and positive predictive value (PPV) for classifying screening, surveillance, and diagnostic colonoscopies. The reference standard was the indication assigned after comprehensive medical record review. RESULTS: For screening indications, the algorithm's sensitivity was 88.5% (95% confidence interval [CI], 80.4%-91.7%), specificity was 91.7% (95% CI, 87.0%-95.1%), and PPV was 83.3% (95% CI, 74.7%-90.0%). For surveillance indications, the algorithm's sensitivity was 93.4% (95% CI, 86.2%-97.5%), specificity was 92.8% (95% CI, 88.4%-95.9%), and PPV was 85.0% (95% CI, 76.5%-91.4%). The algorithm's sensitivity, specificity, and PPV for diagnostic indications were 81.4% (95% CI, 73.0%-88.1%), 96.8% (95% CI, 93.2%-98.8%), and 93.9% (95% CI, 87.2%-97.7%), respectively. LIMITATIONS: Validation was confined to a single healthcare system. CONCLUSION: An algorithm that uses commonly available modern electronic medical data sources yielded a high sensitivity, specificity, and PPV for classifying screening, surveillance, and diagnostic colonoscopy indications. This algorithm had greater accuracy than the indication listed on the colonoscopy report.

High-dose barium impaction therapy for the recurrence of colonic diverticular bleeding: a randomized controlled trial.

OBJECTIVE: We compared the clinical efficacy of barium therapy and conservative therapy in preventing recurrence in patients with diverticular bleeding. BACKGROUND: Previous case reports have indicated that barium impaction therapy provides initial hemostasis for diverticular bleeding and prevention against rebleeding. METHODS: After spontaneous cessation of bleeding, patients were randomly assigned to conservative treatment (n = 27) or high-dose barium impaction therapy (n = 27). Patients were followed up for 1 year after enrollment of the last patient. The main outcome measure was rebleeding. RESULTS: Median follow-up period was 584.5 days. The probability of rebleeding at 30-day, 180-day, 1-year, and 2-year follow-up in all patients was 3.7%, 14.8%, 28.4%, and 32.7%, respectively. By group, probability at 1 year was 42.5% in the conservative group and 14.8% in the barium group (log-rank test, P = 0.04). After adjustment for a history of hypertension, the hazard ratio of rebleeding in the barium group was 0.34 (95% confidence interval, 0.12-0.98). No complications or laboratory abnormalities due to barium therapy were observed. Compared with the conservative group, the barium group had significantly (P < 0.05) fewer hospitalizations per patient (1.7 vs 1.2), units of blood transfused (1.9 vs 0.7), colonoscopies (1.4 times vs 1.1 times), and hospital stay days (15 days vs 11 days) during the follow-up period. No patients died and none required angiographic or surgical procedures in either group. CONCLUSIONS: High-dose barium impaction therapy was effective in the long-term prevention of recurrent bleeding, and reduced the frequency of rehospitalization and need for blood transfusion and colonoscopic examination. ClinicalTrials.gov Identifier, UMIN 000002832.

Oats and bowel disease: a systematic literature review.

Whole-grain foods such as oats may protect against colorectal cancer and have benefits on inflammatory bowel disease and coeliac disease. The present study aimed to systematically review the literature describing intervention studies that investigated the effects of oats or oat bran on risk factors for bowel disease. A literature search was conducted using Embase, Medline and the Cochrane library, which identified 654 potential articles. Thirty-eight articles describing twenty-nine studies met the inclusion criteria. Two studies carried out in participants with a history of colorectal adenomas found no effects of increased oat-bran intake on indirect risk makers for colorectal cancer. One of two interventions with oat bran in patients with ulcerative colitis showed small improvements in the patients' conditions. Most of the eleven studies carried out in adults with coeliac disease showed no negative effects of uncontaminated oat consumption. The fourteen studies carried out in volunteers with no history of bowel disease suggest that oats or oat bran can significantly increase stool weight and decrease constipation, but there is a lack of evidence to support a specific effect of oats on bowel function compared with other cereals. A long-term dietary intake of oats or oat bran could benefit inflammatory bowel disorders, but this remains to be proven. A protective effect on colorectal adenoma and cancer incidence has not yet been convincingly shown. The majority of patients with coeliac disease could consume up to 100 g/d of uncontaminated oats, which would increase the acceptability of, and adherence to, a gluten-free diet.

Lesiones de colon diagnosticadas por colonoscopia en pacientes con sangre oculta positiva / Colon lesion diagnosed by colonoscopy in patients with hidden positive blood

Se realizó un estudio observacional, descriptivo, transversal, a todos los pacientes con sangre oculta positiva en heces fecales, a los cuales se le realizó colonoscopia, en el servicio de gastroenterología del Hospital Universitario Clínico Quirúrgico Comandante Faustino Pérez, de Matanzas, en el período comprendido de junio 2013 a junio 2014, con universo de 104 pacientes, previo consentimiento informado, con el objetivo de caracterizar las lesiones diagnosticadas. Se confeccionó una planilla de recolección de información (edad, sexo, positividad de colonoscopia y lesiones diagnosticadas). Los resultados se representaron en números y por cientos, mediante tablas o gráficos. Se concluyó que predominaron los pacientes entre 50 y 55 años, el sexo femenino, de ellos el 76,92 por ciento presentó algún tipo de lesión en el colon, 15,09 por ciento con cáncer de colon y 2,83 por ciento cáncer de recto, lo cual reafirma la importancia de este método de pesquisa para el diagnóstico precoz de estas patologías(AU)

We carried out an observational, descriptive, cross-sectional study to all the patients with hidden positive blood in fecal feces who were submitted to colonoscopy in the gastroenterology service of the Teaching Clinic-Surgical Hospital Faustino Pérez, of Matanzas, in the period from June 2013 to June 2014; the universe were 104 patients who gave their previous informed consent, and the aim was characterizing the diagnosed lesions. We elaborated a form for collecting information (age, gender, colonoscopy positivity and diagnosed lesions). Results were given in numbers and percents and displayed in tables and pictures. We arrived to the conclusion that there was a predominance of female patients aged 50-55 years; 76,92 percent of them had some kind of colon lesions; 15,09 percent had colon cancer and 2,83 percent rectum cancer, confirming the importance of this testing method for the precocious diagnosis of these pathologies(AU)

Probiotic Escherichia coli CFR 16 producing pyrroloquinoline quinone (PQQ) ameliorates 1,2-dimethylhydrazine-induced oxidative damage in colon and liver of rats.

Inflammation of the gastrointestinal tract is associated with reactive oxygen species (ROS) genesis. Alleviation of oxidative stress is achieved by using antioxidants and probiotics. Present study investigates a synergistic effect of the probiotic Escherichia coli CFR 16 containing Vitreoscilla haemoglobin gene (vgb), green fluorescent protein (gfp) gene and pyrroloquinoline quinone (pqq) gene cluster on oxidative stress induced by 1,2-dimethylhydrazine (DMH). Adult virgin Charles foster male rats (3-4 months) weighing 200-250 g were administered with DMH (25 mg/kg body weight, s.c.) twice a week for eight consecutive weeks. Rats receiving only DMH dose showed increased lipid peroxidation in liver and intestinal tissues with reduced activity of antioxidant enzymes, i.e. superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Oral dose of E. coli CFR 16::vgb-gfp harbouring pqq gene cluster increased rat faecal PQQ concentration by twofold, reduced lipid peroxidation and retained SOD, CAT and GPx activities close to normal levels in liver and colonic tissues following DMH treatment. In addition, significant protection was found in colonic histological sections of these rat groups. This study demonstrates a protective efficacy in the following order: E. coli CFR 16 < E. coli CFR 16::vgb-gfp < vitamin C = PQQ < E. coli CFR 16::vgb-gfp (pqq).

Prevention of colonic spasm using L-menthol in colonoscopic examination.

PURPOSE: The detailed efficacy of intraluminal L-menthol for preventing colonic spasm is not known. The aim of this study was to evaluate the effectiveness of L-menthol in preventing colonic spasm during colonoscopy. METHODS: We analyzed 65 patients (mean age: 71.7 years; 49 men and 16 women) who were administered 0.8% L-menthol (MINCLEA, Nihon Seiyaku, Tokyo, Japan) intraluminally for severe colonic spasm during colonoscopic examination at Kyoto Prefectural University of Medicine between February 2012 and May 2013. The efficacy of L-menthol was defined as the absence of colonic spasm during a period of 30 s, and its effect was evaluated at 30 s, 1 min, and 5 min after administration. Additionally, various characteristics of these patients were analyzed. Twenty-seven patients with severe colonic spasm were administered intraluminal water and assessed as controls. RESULTS: L-Menthol was effective in preventing colonic spasms in 60.0%, 70.8%, and 46.5% of patients at 30 s, 1 min, and 5 min, respectively. In contrast, water was effective in 22.2%, 29.6%, and 48.1% of patients at 30 s, 1 min, and 5 min, respectively. There was a significant difference about the efficacy at 30 s and 1 min between L-menthol and water (P = 0.0009, P = 0.0006). CONCLUSIONS: L-Menthol (0.8%) was effective in preventing colonic spasm during colonoscopic examination.

Does sedation type affect colonoscopy perforation rates?

BACKGROUND: Sedation with propofol is gaining popularity. It is unclear whether sedation with propofol is associated with colonoscopic perforation. OBJECTIVE: The purpose of this study was to compare perforation rates during colonoscopy using sedation with or without propofol. DESIGN: This was a retrospective case series study. SETTINGS: Data from a tertiary center were analyzed. Demographics, method of sedation, and type of endoscopic procedure performed were collected. PATIENTS: Patients who underwent a colonoscopy from January 2003 to October 2012 were analyzed. MAIN OUTCOME MEASURES: Perforation rate expressed per 10,000 colonoscopies was measured. RESULTS: A total of 118,004 colonoscopies were performed during the study period, with 48 perforations (0.041% or 4.1 per 10,000). Overall, the use of propofol was associated with a 2.5 times increased rate of perforation (6.9 vs 2.7 per 10,000; p = 0.0015). Similarly, in patients undergoing therapeutic colonoscopies, there was a 3.4-times increased risk of perforation associated with the use of propofol (8.7 vs 2.6 per 10,000; p = 0.0016). However, in patients undergoing diagnostic colonoscopies, there was no significantly increased risk of perforation with the use of propofol (4.2 vs 2.9 per 10,000; p = 0.64). In univariate and multivariate analyses, there were no differential perforation risks on the basis of sex, but each decade increase in age was associated with an increased risk of perforation. In those patients having a therapeutic colonoscopy, age (per decade) and propofol use were independently and significantly associated with an increased perforation risk, with adjusted ORs of 1.32 (p = 0.04) and 3.38 (p = 0.001). LIMITATIONS: This was a retrospective study with the potential for selection bias. CONCLUSIONS: This study shows that propofol administration is associated with an increased risk of colonoscopic perforation among patients undergoing a therapeutic colonoscopy; however, this association was not evident in patients undergoing a diagnostic colonoscopy. Further studies, such as a prospective, randomized clinical trial, should be done to further evaluate this association.

Chemopreventive effects of aloin against 1,2-dimethylhydrazine-induced preneoplastic lesions in the colon of Wistar rats.

Chemoprevention opens new window in the prevention of all types of cancers including colon cancer. Aloin, an anthracycline in plant pigment, can be utilized as a protective agent in cancer induction. In the present study, we have evaluated the chemopreventive efficacy of aloin against 1,2-dimethylhydrazine (DMH)-induced preneoplastic lesions in the colon of Wistar rats. DMH-induced aberrant crypt foci (ACF) and mucin-depleted foci (MDF) have been used as biomarkers of colon cancer. Efficacy of aloin against the colon toxicity was evaluated in terms of biochemical estimation of antioxidant enzyme activities, lipid peroxidation, ACF, MDF, histopathological changes, and expression levels of molecular markers of inflammation and tumor promotion. Aloin pretreatment ameliorates the damaging effects induced by DMH through a protective mechanism that involved reduction in increased oxidative stress enzymes (p < 0.001), ACF, MDF, cyclooxygenase-2, inducible nitric oxide synthase, interleukin-6, proliferating cell nuclear antigen protein expression, and tumor necrosis factor-α (p < 0.001) release. From the results, it could be concluded that aloin clearly protects against chemically induced colon toxicity and acts reasonably by inducing antioxidant level, anti-inflammatory and antiproliferative markers.