Wood hemicelluloses exert distinct biomechanical contributions to cellulose fibrillar networks.

Hemicelluloses, a family of heterogeneous polysaccharides with complex molecular structures, constitute a fundamental component of lignocellulosic biomass. However, the contribution of each hemicellulose type to the mechanical properties of secondary plant cell walls remains elusive. Here we homogeneously incorporate different combinations of extracted and purified hemicelluloses (xylans and glucomannans) from softwood and hardwood species into self-assembled networks during cellulose biosynthesis in a bacterial model, without altering the morphology and the crystallinity of the cellulose bundles. These composite hydrogels can be therefore envisioned as models of secondary plant cell walls prior to lignification. The incorporated hemicelluloses exhibit both a rigid phase having close interactions with cellulose, together with a flexible phase contributing to the multiscale architecture of the bacterial cellulose hydrogels. The wood hemicelluloses exhibit distinct biomechanical contributions, with glucomannans increasing the elastic modulus in compression, and xylans contributing to a dramatic increase of the elongation at break under tension. These diverging effects cannot be explained solely from the nature of their direct interactions with cellulose, but can be related to the distinct molecular structure of wood xylans and mannans, the multiphase architecture of the hydrogels and the aggregative effects amongst hemicellulose-coated fibrils. Our study contributes to understanding the specific roles of wood xylans and glucomannans in the biomechanical integrity of secondary cell walls in tension and compression and has significance for the development of lignocellulosic materials with controlled assembly and tailored mechanical properties.

Identification of rhein as the metabolite responsible for toxicity of rhubarb anthraquinones.

Rhubarb is a popular food in Europe with laxative properties attributed to anthraquinones. Long term usage of rhubarb anthraquinones has been linked to colonic toxicity, including the formation of melanosis coli, which is associated with increased risk of colon cancer. The major purgative anthraquinone in rhubarb is thought to be sennoside A, which is metabolised by colonic microflora. Here, we sought to identify the toxic metabolite responsible for melanosis coli in rats dosed with rhubarb anthraquinones for up to 90 days. Three metabolites were detected in rat faeces using HPLC. Of these, rhein was identified as the metabolite that accumulated most over time. Fecal flora from treated rats were capable of greater biotransformation of sennoside A to rhein compared to that from control rats. Cell culture experiments suggested that apoptosis and autophagy induced by rhein is the likely mechanism of chronic toxicity of rhubarb anthraquinones.

Effectiveness of very low-volume preparation for colonoscopy: A prospective, multicenter observational study.

BACKGROUND: The effectiveness of colonoscopy strictly depends on adequate bowel cleansing. Recently, a 1 L polyethylene glycol plus ascorbate (PEG-ASC) solution (Plenvu; Norgine, Harefield, United Kingdom) has been introduced on the evidence of three phase-3 randomized controlled trials, but it had never been tested in the real-life. AIM: To assess the effectiveness and tolerability of the 1 L preparation compared to 4 L and 2 L- PEG solutions in a real-life setting. METHODS: All patients undergoing a screening or diagnostic colonoscopy after a 4, 2 or 1 L PEG preparation, were consecutively enrolled in 5 Italian centers from September 2018 to February 2019. The primary endpoints of the study were the assessment of bowel cleansing success and high-quality cleansing of the right colon. The secondary endpoints were the evaluation of tolerability, adherence and safety of the different bowel preparations. Bowel cleansing was assessed through the Boston Bowel Preparation Scale. Adherence was defined as consumption of at least 75% of each dose, while tolerability was evaluated through a semi-quantitative scale. Safety was systematically monitored through adverse events reporting. RESULTS: Overall, 1289 met the inclusion criteria and were enrolled in the study. Of these, 490 patients performed a 4 L-PEG preparation (Selgesse®), 566 a 2 L-PEG cleansing (Moviprep® or Clensia®) and 233 a 1 L-PEG preparation (Plenvu®). Bowel cleansing by Boston Bowel Preparation Scale was 6.5 ± 1.5 overall and 6.3 ± 1.5, 6.2 ± 1.5, 7.3 ± 1.5 (P < 0.001) in the subgroups of 4 L, 2 L and 1 L-PEG preparation, respectively. Cleansing success was achieved in 72.4%, 74.1% and 90.1% (P < 0.001), while a high-quality cleansing of the right colon in 15.9%, 12.0% and 41.4% (P < 0.001) for 4 L, 2 L and 1 L-PEG preparation groups, respectively. The 1 L preparation was the most tolerated compared to the 2 and 4 L-PEG solutions in the absence of serious adverse events within any of the three groups. Multiple regression models confirmed 1 L PEG-ASC preparation as an independent predictor of overall cleansing success, high-quality cleansing of the right colon and of tolerability. CONCLUSION: This study supports the effectiveness and tolerability of 1 L PEG-ASC, also showing it is an independent predictor of overall cleansing success, high-quality cleansing of the right colon and of tolerability.

Molecular properties and gut health benefits of enzyme-hydrolyzed konjac glucomannans.

Konjac glucomannan (KGM) with a molecular weight (MW) of 823.4 kDa was partially degraded by endo-1,4-ß-mannanase. Two hydrolyzed KGM fractions (KGM-M-1: 147.2 kDa and KGM-M-2: 21.5 kDa) were characterized and applied to the animal tests in comparison with the native KGM. After oral feeding to the mice, KGM-M-1 and KGM-M-2 significantly increased the levels of short chain fatty acids (SCFAs) in the colonic contents and the native KGM increased the SCFAs in the cecum. The more significant effect of the native KGM in the cecum may be attributable to its high viscosity, slowing down the movement of intestinal microflora through the cecum, while the lower MW KGM-M-1 and KGM-M-2 could move more easily through the colon to be fermented by colonic bacteria. This new finding may be useful for future research and development of low-MW KGM polysaccharides through enzyme hydrolysis for the desired gut health benefits.

Efficacy of low-dose versus high-dose simethicone with polyethylene glycol for bowel preparation: A prospective randomized controlled trial.

BACKGROUND AND AIM: Additional simethicone (SIM) can improve adequate bowel preparation and adenoma detection rate (ADR). However, there is no consensus on the optimal dose of SIM. In this study, we compared the adequate bowel preparation rate with supplementation of split-dose 2 L polyethylene glycol (PEG) with low-dose SIM (200 mg) versus high-dose SIM (1200 mg). METHODS: This was a prospective, randomized, observer-blinded trial involving consecutive subjects undergoing colonoscopy. The primary outcome was adequate bowel preparation as assessed by Boston Bowel Preparation Scale (BBPS) score. RESULTS: Four hundred subjects were randomly allocated to low-dose SIM or high-dose SIM group. Baseline characteristics were comparable in the two groups (P > 0.05). No significant between-group differences were observed with respect to total bubble scale (BS) (8.49 ± 1.00 vs 8.39 ± 1.10, P = 0.07), total BBPS score (8.70 ± 0.81 vs 8.29 ± 1.18, P = 0.98), ADR (33.68% vs 31.79%, P = 0.69) or withdrawal time (13 [range, 10-16] min vs 13 [10-15] min, P = 0.96). The intubation time in low-dose SIM group was significantly shorter than that in high-dose SIM group (8 (4-16) min vs 10 [6-17] min, P = 0.04). In addition, BS scores as well as diminutive ADR in right colon were superior in the low-dose SIM group (2.68 ± 0.59 vs 2.52 ± 0.73, P = 0.03 and 54.29% vs 30.30%, P = 0.046, respectively). CONCLUSION: Addition of low-dose SIM to split-dose 2 L PEG was as effective as addition of high-dose SIM with respect to adequate bowel preparation, ADR and patient tolerance. However, low-dose SIM was superior with respect to intubation time, right colon BS scores, right colon diminutive ADR and cost savings.

The effect of a mixture of 2.7% sorbitol-0.54% mannitol solution on blood coagulation: an invitro, observational healthyvolunteer study using rotational thromboelastometry (ROTEM).

BACKGROUND: We investigated the effect of irrigation fluid on coagulation according to the hemodilution level using rotational thromboelastometry (ROTEM). METHODS: Venous blood was taken from 12 healthy volunteers and divided into four specimen tubes that were diluted to various levels (0%, 10%, 20%, and 40%) using an irrigation fluid composed of 2.7% sorbitol and 0.54% mannitol. RESULTS: Significant prolongation of clotting time was observed in the 40% diluted sample using both INTEM (P = 0.009) and EXTEM (P = 0.001) assays. However, the clot formation time was prolonged significantly in the 10%, 20%, and 40% diluted samples using both INTEM (P < 0.001) and EXTEM (P = 0.002, P < 0.001, and P < 0.001, respectively) assays. A significant decrease of α-angle of INTEM and EXTEM were observed in the 10% (P < 0.001), 20% (P < 0.001 and P = 0.001, respectively), and 40% (P < 0.001) groups compared with the 0% dilution group. The maximum clot firmness (MCF) of INTEM decreased significantly in the 20% (P < 0.001) and 40% (P < 0.001) diluted samples. In the MCF of EXTEM and FIBTEM assays, 10% (P = 0.009 and P = 0.015, respectively), 20% (P = 0.001), and 40% (P < 0.001) samples showed a significant decrease compared with the 0% sample. Nevertheless, most of the ROTEM values were within the reference range, except the 40% sample. CONCLUSIONS: Blood became hypocoagulable when it was diluted in vitro with a fluid composed of 2.7% sorbitol and 0.54% mannitol.

Factors influencing the properties and the stability of spray-dried Sennae fructus extracts.

OBJECTIVE: The objective of this study was to characterize the properties of aqueous Sennae fructus extracts prepared by spray-drying at varying process conditions. SIGNIFICANCE: From an industrial point of view it is essential to develop a formulation which has a constant quality over the whole period of its specified shelf-life. METHOD: Sennae fructus extracts were spray-dried with different atomizing gas pressures, pump feed rates, and inlet temperatures. The extracts were analyzed for their physical properties and stored at accelerated conditions. Sennoside degradation was monitored by HPLC analysis. RESULTS: An increase of the atomizing gas pressure had the most pronounced influence on the decrease of moisture content and particle size. An increase of the inlet temperature led to a decrease of moisture content and particle density, as well as an increase of smooth particle amount. An increase in the pump feed rate, increased the moisture content and resulted in stable hollow spheres. The different conditions also led to smooth or wrinkled particle surfaces, and to golfball, donut, and shard particle shapes. The chemical stability of the sennosides differed from each other after storage. Stability-reducing factors were the moisture content of the samples and their hygroscopicities, as well as different particle morphologies. These factors were influenced by the inlet temperature of the spray-drying process. High inlet temperatures led to a positive influence on dryness and particle morphology and therefore on the stability of the sennosides. CONCLUSIONS: Variation of the process conditions affected the resulting particle properties and their storage stability of Sennae fructus extract.

Layer-by-layer films containing emodin or emodin encapsulated in liposomes for transdermal applications.

Dermal drug release systems are an important area of research because they can be applied to the skin in a non-invasive procedure using a lower concentration of drugs. In this study, we have developed two types of Layer-by-Layer (LbL) films for releasing emodin (EM). In one system, EM was intercalated with poly(ethylenimine) PEI and poly(vinyl sufonate) (PVS) polyelectrolytes, forming (PEI/PVS)2(PEI/EM)7; in another, EM was incorporated in liposomes obtained by mixing dipalmitoyl phosphatidyl glycerol (DPPG) and palmitoyl oleoyl phosphatidyl glycerol (POPG) lipids, forming (PEI/PVS)2(PEI/DPPG-POPG-EM)7. UV-vis and FTIR spectroscopies were used to characterize the LbL films. These showed that the depositions of material by LbL were efficient, with increases in the absorbance of each bilayer evidencing the presence of EM in the film. The (PEI/PVS)2(PEI/EM)7 and (PEI/PVS)2(PEI/DPPG-POPG-EM)7 films released EM in three and five days, respectively. The cyclic voltammetry (CV) assay of the (PEI/PVS)2(PEI/EM)7 results are in agreement with UV-vis measurements, which suggest that EM was protonated in acid environments, while the CV of (PEI/PVS)2(PEI/DPPG-POPG-EM)7 demonstrated distinct protonation behaviour for EM within the inner liposome structure, even in acid solutions. Therefore, this study presents two systems based on LbL films and provides additional details about the release of EM from these films to create a viable alternative for transdermal applications.

Resin glycosides from Convolvulaceae plants.

Resin glycosides are well known as purgative ingredients, which are characteristic of certain crude drugs such as Mexican Scammony Radix, Orizabae Tuber, and Jalapae Tuber, all of which originate from Convolvulaceae plants. Depending on their solubility in ether, these are roughly classified into two groups-jalapin (soluble) and convolvulin (insoluble). Almost all jalapins hitherto isolated and characterized had common intramolecular macrocyclic ester structures. These are composed of 1 mol of oligoglycoside of hydroxyl fatty acid (glycosidic acid) partially acylated by some organic acids at the sugar moiety, some examples of which are ester-type dimers. On the other hand, convolvulin is regarded as an oligomer of a variety of acylated glycosidic acids. This review describes the isolation and structural elucidation of resin glycosides from some Convolvulaceae plants, including Ipomoea operculata, Pharbitis nil, Quamoclit pennata, Calystegia soldanella, and I. muricata.

MOST: most-similar ligand based approach to target prediction.

BACKGROUND: Many computational approaches have been used for target prediction, including machine learning, reverse docking, bioactivity spectra analysis, and chemical similarity searching. Recent studies have suggested that chemical similarity searching may be driven by the most-similar ligand. However, the extent of bioactivity of most-similar ligands has been oversimplified or even neglected in these studies, and this has impaired the prediction power. RESULTS: Here we propose the MOst-Similar ligand-based Target inference approach, namely MOST, which uses fingerprint similarity and explicit bioactivity of the most-similar ligands to predict targets of the query compound. Performance of MOST was evaluated by using combinations of different fingerprint schemes, machine learning methods, and bioactivity representations. In sevenfold cross-validation with a benchmark Ki dataset from CHEMBL release 19 containing 61,937 bioactivity data of 173 human targets, MOST achieved high average prediction accuracy (0.95 for pKi ≥ 5, and 0.87 for pKi ≥ 6). Morgan fingerprint was shown to be slightly better than FP2. Logistic Regression and Random Forest methods performed better than Naïve Bayes. In a temporal validation, the Ki dataset from CHEMBL19 were used to train models and predict the bioactivity of newly deposited ligands in CHEMBL20. MOST also performed well with high accuracy (0.90 for pKi ≥ 5, and 0.76 for pKi ≥ 6), when Logistic Regression and Morgan fingerprint were employed. Furthermore, the p values associated with explicit bioactivity were found be a robust index for removing false positive predictions. Implicit bioactivity did not offer this capability. Finally, p values generated with Logistic Regression, Morgan fingerprint and explicit activity were integrated with a false discovery rate (FDR) control procedure to reduce false positives in multiple-target prediction scenario, and the success of this strategy it was demonstrated with a case of fluanisone. In the case of aloe-emodin's laxative effect, MOST predicted that acetylcholinesterase was the mechanism-of-action target; in vivo studies validated this prediction. CONCLUSIONS: Using the MOST approach can result in highly accurate and robust target prediction. Integrated with a FDR control procedure, MOST provides a reliable framework for multiple-target inference. It has prospective applications in drug repurposing and mechanism-of-action target prediction.

A Model Prediction for Chenodeoxycholate Aggregate Formation.

A relationship between the chenodeoxycholate (CDC) monomer concentration and the total concentration of CDC was established using a kinetic dialysis technique. Meanwhile, the sizes of the formed simple CDC micelles were measured by a quasielastic light-scattering (QLS) technique to be nearly constant. The QLS results led to a suggestion for equilibrium models of CDC aggregate formation. According to the established relationship and the suggested models, the best curve-fitting model was selected by a least-squares technique. Furthermore, the model parameters were quantified. Based on the quantified parameters, at a minimum detectable concentration of simple CDC micelles to be ∼0.2 mM, an appropriate model corresponding concentration of CDC monomers was estimated to be ∼3.08 mM. This value is consistent with a minimum monomer CDC concentration of ∼3.13 mM for simple CDC micelle formation estimated according to the present QLS detection and the model prediction. The consistency confirms the model prediction that at a low CDC monomer concentration (<3 mM), the concentration of stable CDC dimers is much higher than that of simple CDC micelles but the contribution of simple CDC micelles to the total CDC concentration cannot be negligible.

[Comparative Study on Bowel Preparation Efficacy of Ascorbic Acid Containing Polyethylene Glycol by Adding Either Simethicone or 1 L of Water in Health Medical Examination Patients: A Prospective Randomized Controlled Study].

BACKGROUND/AIMS: There are no studies that looked into the bubble eliminating efficacy of polyethylene glycol with ascorbic acid (PEGA), which has been one of the shortcomings of polyethylene glycol (PEG). In this study, we compared newly introduced PEGA regimen by adding either simethicone or 1 L of water. METHODS: A prospective randomized controlled study was carried out at Dongguk Universtiy Gyeongju Hospital from July 2014 to September 2014. A total of 90 patients were randomly assigned to 3 groups; PEGA group (n=30) which served as control, simethicone addition group (n=30) to which simethicone 400 mg was additionally prescribed, and water addition group (n=30) to whom additional 1 L of water was given. Cleansing effectiveness, gas elimination efficacy, side effects, and patient satisfaction were compared between the groups. RESULTS: PEGA group demonstrated the highest cleansing effectiveness, but there was no statistically significant difference among the groups. Simethicone addition group showed significantly lesser amount of bubbles than the other groups (2.57±2.05 vs. 1.10±1.83 vs. 2.60±2.84, p=0.017). The rates of side effects in each group were 20.00% vs. 16.77% vs. 53.33%. Water addition group had significantly more side effects than the PEGA group and the simethicone addition group (p=0.003). The patient satisfaction score of each group was 3.37±0.85 vs. 3.73±0.74 vs. 3.20±0.66 with simethicone addition group showing significantly higher satisfaction than water addition group (p=0.020). CONCLUSIONS: PEGA bowel preparation agent showed satisfactory bowel cleansing despite the decrease in dosage, and addition of simethicone resulted in better bubble elimination.

Serum Albumin Concentrations Predict hypovolaemia Caused by Polyethylene Glycol Plus Ascorbic Acid Prior to Colonoscopy in Elderly Patients.

BACKGROUND: Previous studies have confirmed the safety of polyethylene glycol plus ascorbic acid for healthy middle-aged adults but not for the elderly. The osmotic pressure of polyethylene glycol plus ascorbic acid is approximately twice that of plasma osmolality and may cause dehydration. OBJECTIVE: In this study, we determined whether dehydration was induced in elderly patients by polyethylene glycol plus ascorbic acid, and we analysed the data obtained in order to identify predictors of dehydration. METHODS: This was a prospective, uncontrolled, before-and-after intervention study. All patients older than 65 years who underwent colonoscopies at the Moji Medical Center were administered polyethylene glycol plus ascorbic acid prior to colonoscopy. Clinical variables before and after bowel preparation were measured and analysed statistically. A multiple linear regression analysis was performed to identify predictors of dehydration due to this procedure. RESULTS: Eighty-three patients were assessed for eligibility, and 74 clinical variables were ultimately analysed. A significant increase in the red blood cell count (4.10 versus 4.25 × 10(6)/mm(3)), haemoglobin level (12.4 versus 13.0 g/dL) and haematocrit (38.1% versus 39.4%) suggested the presence of hypovolaemia after the procedure (P < 0.001). The serum concentration of albumin before bowel preparation was identified as the only significant predictor of hypovolaemia (ß = 0.47, P = 0.0001, adjusted R (2) = 0.22). CONCLUSION: The serum concentration of albumin before bowel preparation predicted hypovolaemia caused by polyethylene glycol plus ascorbic acid in elderly patients. Therefore, care is needed in order to prevent hypovolaemia, especially in elderly patients with hypoalbuminaemia. TRIAL REGISTRATION: No. 000015724 (University Hospital Medical Information Network Center).

[Effects of a Patient Educational Video Program on Bowel Preparation Prior to Colonoscopy].

PURPOSE: The purpose of this study was to evaluate the effects of an educational video program on bowel preparation for a colonoscopy. METHODS: The study used a non-equivalent control group and non-synchronized design as a quasi-experimental research involving 101 participants undergoing bowel preparation for a colonoscopy (experimental group 51, control group 50 subjects) at W. university hospital, from Aug. 7 to Oct. 31, 2013. The control group received verbal education with an explanatory note while the experimental group received education using a video program. To measure knowledge of diet restrictions and compliance with ingesting bowel preparation solutions, a questionnaire, based on The Korean Society of Gastrointestinal Endoscopy's Guide (2003), developed by Sam-Sook You, was used after revisions and supplementation was done. To measure bowel cleanness, the 'Aronchick Bowel Preparation Scale' was adopted. Data were analyzed using the SPSS WIN 12.0 program. RESULTS: A higher proportion of the experimental group showed a positive change in knowledge level on diet restrictions (U=1011.50, p=.035) and ingestion of bowel preparation solutions (U=980.50, p=.019), a higher level of compliance with diet restrictions (U=638.50, p<.001), ingesting bowel preparation solutions (U=668.00, p<.001) and the level of bowel cleanness (χ²=17.00, p<.001) than the control group. CONCLUSION: The results of this study indicate that a video educational program for patients having a colonoscopy can improve knowledge, level of compliance with diet restrictions, ingestion of bowel preparation solutions, and bowel cleanness. Therefore video educational program should be used with this patient group.

Investigations of bisacodyl with modified ß-cyclodextrins: Characterization, molecular modeling, and effect of PEG.

Bisacodyl inclusion into hydroxypropyl-ß-cyclodextrin and 2,6-di-O-methyl-ß-cyclodextrin cavities was experimentally and theoretically investigated, and the effect of PEG 4000 on these inclusions was studied. Isothermal calorimetry titration curves indicated that the binary inclusion processes are enthalpy- and entropy-driven. The solid-state complexes were fully characterized by FT-IR, XRPD, DSC and SEM analyses. FT-IR, (1)H NMR, and ROESY studies provided the most favorable encapsulation modes of binary complexes, and results were further confirmed by molecular docking and molecular dynamics studies. The presence of PEG 4000 slightly enhanced encapsulation efficiency, solubility and dissolution rates of the binary complexes. In vivo studies showed that complexes with CDs markedly accelerated gastrointestinal transit time compared with pure bisacodyl, whereas addition of PEG 4000 showed no further significant improvement of the bioavailability.

[Filtration of active fractions with function of expelling water retention with drastic purgative from Kansui Radix stir-baked with vinegar].

To study the function of expelling water retention with drastic purgative of different polarities of Kansui Radix stir-baked with vinegar on the cancerous ascites model rats, the furosemide was taken as positive control drug, and the cancerous ascites model rats were respectively orally administered with different polarities of Kansui Radix stir-baked with vinegar for 7 d. The amount of urine and ascites, the level of urinary sodium, potassium, chloride ion and pH, and the content of PRL1, AII, ALD in serum were investigated. Compared with model groups, ethyl acetate extract group showed a decreasing trend in ascites; the amount of urine of showed a significant increase (P < 0.05); the level of urinary sodium, potassium, chloride ion (P < 0.05, P < 0.01), pH (P < 0.05), and the content of PRL1, AII, ALD in serum all showed a significant decrease (P < 0.01). The effects of petroleum ether extract and n-butanol extract were weaker than that of ethyl acetate extract. The water exact was the weakest. The results showed that ethyl acetate extract is the active part of Kansui Radix stir-baked with vinegar on the function of expelling water retention with drastic purgative on the cancerous ascites model rats, alleviating the water-electrolyte disorder and body fluid acid-base imbalance, regulating the renin angiotensin aldosterone system.

Effects of a Patient Educational Video Program on Bowel Preparation Prior to Colonoscopy

PURPOSE: The purpose of this study was to evaluate the effects of an educational video program on bowel preparation for a colonoscopy. METHODS: The study used a non-equivalent control group and non-synchronized design as a quasi-experimental research involving 101 participants undergoing bowel preparation for a colonoscopy (experimental group 51, control group 50 subjects) at W. university hospital, from Aug. 7 to Oct. 31, 2013. The control group received verbal education with an explanatory note while the experimental group received education using a video program. To measure knowledge of diet restrictions and compliance with ingesting bowel preparation solutions, a questionnaire, based on The Korean Society of Gastrointestinal Endoscopy's Guide (2003), developed by Sam-Sook You, was used after revisions and supplementation was done. To measure bowel cleanness, the 'Aronchick Bowel Preparation Scale' was adopted. Data were analyzed using the SPSS WIN 12.0 program. RESULTS: A higher proportion of the experimental group showed a positive change in knowledge level on diet restrictions (U=1011.50, p=.035) and ingestion of bowel preparation solutions (U=980.50, p=.019), a higher level of compliance with diet restrictions (U=638.50, p<.001), ingesting bowel preparation solutions (U=668.00, p<.001) and the level of bowel cleanness (chi2=17.00, p<.001) than the control group. CONCLUSION: The results of this study indicate that a video educational program for patients having a colonoscopy can improve knowledge, level of compliance with diet restrictions, ingestion of bowel preparation solutions, and bowel cleanness. Therefore video educational program should be used with this patient group.

Thermal degradation behavior and kinetic analysis of spruce glucomannan and its methylated derivatives.

The thermal degradation behavior and kinetics of spruce glucomannan (SGM) and its methylated derivatives were investigated using thermogravimetric analysis to characterize its temperature-dependent changes for use in specific applications. The results were compared with those obtained for commercial konjac glucomannan (KGM). The SGM and the KGM exhibited two overlapping peaks from 200 to 375°C, which correspond to the intensive devolatilization of more than 59% of the total weight. Differences in the pyrolysis-product distributions and thermal stabilities appeared as a result of the different chemical compositions and molecular weights of the two GMs. The Friedman and Flynn-Wall-Ozawa isoconversional methods and the Coats-Redfern were adopted to determine the kinetic triplet of the intensive devolatilization region. Both GMs can be modeled using a complex mechanism that involves both a Dn-type and an Fn-type reaction. The comparative study of partially methylated GM indicated higher homogeneity and thermal resistance for the material with the higher degree of substitution.

Monitoring of 29 weight loss compounds in foods and dietary supplements by LC-MS/MS.

Because of the rapid growth in dietary supplement availability and public concern for weight control, the investigation of foods and various dietary supplements illegally adulterated with weight loss compounds has become increasingly important. A total of 29 weight loss compounds, including sennoside, sibutramine, ephedrine and their analogues, found to be adulterated in foods and dietary supplements were simultaneously examined by LC-MS/MS. The 188 samples were collected between 2009 and 2012 in South Korea, and method validation was performed to determine the adulterants to the weight loss compounds. LODs, LOQs and linearity ranged from 0.03 to 7.5 ng ml⁻¹, from 0.08 to 30.00 ng ml⁻¹, and from 0.990 to 0.999, respectively. The results showed that nine weight loss compounds, namely bisacodyl, desmethylsibutramine, didesmethylsibutramine, ephedrine, fluoxetine, pseudoephedrine, sennoside A, sennoside B and sibutramine, were detected in 62 of all collected samples and were found in order of frequency as follows: sibutramine, 25.7%; sennoside A, 22.9%; sennoside B, 20.0%; fluoxetine, 8.6%; desmethylsibutramine, 7.1%; bisacodyl, ephedrine, and pseudoephedrine, 4.3%; and didesmethylsibutramine, 2.9%. Sibutramine, which was the most frequently found adulterant, ranged in levels from 0.03 to 132.40 mg g⁻¹ (2010), from 0.88 to 76.2 mg g⁻¹ (2011), and from 0.07 to 0.24 mg g⁻¹ (2012). Although the concentrations of most compounds ranged widely, some compounds such as bisacodyl and fluoxetine were found at high concentrations in several samples.

Sugar-free menthol candy drops improve the palatability and bowel cleansing effect of polyethylene glycol electrolyte solution.

BACKGROUND: Colon preparations are generally poorly tolerated. OBJECTIVE: To study the efficacy of sugar-free candy drops in improving palatability and tolerability of polyethylene glycol electrolyte solution (PEG-E). DESIGN: Single-blind, randomized, controlled trial. SETTING: University medical center. PATIENTS: Ambulatory patients scheduled for elective colonoscopy. INTERVENTION: Menthol candy drops. Patients were randomly assigned to split-dose, 4-L, PEG-E ± cough drops. Palatability was assessed on a linear scale of 1 to 5 (1 = disgusting; 5 = tasty). Quality of preparation, remaining unconsumed volume, and side effects were secondary outcomes. MAIN OUTCOME MEASUREMENTS: Palatability and tolerability of PEG-E. RESULTS: A total of 99 patients were enrolled (50 control group, 49 candy drops-added group). The mean (± standard deviation) palatability score was significantly better in candy drop users versus controls (3.9 ± 0.7 vs 2.8 ± 1.2, respectively; P < .001) as were the preparations scored as excellent (63.3% vs 34% of controls; P = .004). Side effects were similar except for nausea (24.5% candy drops vs 44% controls; P = .04). The amount of unconsumed PEG-E was not different between candy drop and control groups (128 [± 361 mL] versus 69 [± 194 mL], respectively; P = .32) but was significantly lower in excellent grade preparations versus other grades (31 [± 103 mL] versus 162 [± 384 mL], respectively; P = .024). On multivariate logistic regression, an excellent preparation was associated with candy drops (odds ratio [OR] 3.3, 95% confidence interval [CI], 1.4-7.8; P = .006) and smaller unconsumed volume of same-day PEG-E [OR 0.996, 95% CI, 0.992-1.000; P = .044). LIMITATIONS: Single-center study. CONCLUSION: Sugar-free menthol candy drops are a safe and effective addition to split-dose PEG-E, resulting in improved tolerability and patient compliance, which appears to translate into improved bowel cleansing. ( CLINICAL TRIAL REGISTRATION NUMBER: NCT01541683.).