Establishment of high-performance liquid chromatography-photodiode array method for 43 weight loss agents and effect of basic environment on bisacodyl degradation.

RATIONALE: The demand for weight loss products is increasing as slimness emerges as the new aesthetic standard and people's desire to achieve it increases. In addition, the distribution and sale of products containing illegal ingredients, pharmaceuticals, and chemicals for which safety is not guaranteed and that cannot be used as foods or dietary supplements are increasing. Thus, the development of an analytical method that could monitor these illegal products is required. METHODS: A high-performance liquid chromatography-photodiode array method capable of rapid and reliable qualitative and quantitative analyses of 43 weight loss agents was established and validated. RESULTS: The process involved dividing analytes into three groups for rapid analysis; when bisacodyl was mixed with chlorocyclopentylsibutramine, it decomposed into its metabolites: monoacetyl bisacodyl and bis-(p-hydroxypheny)-pyridyl-2-methane. This decomposition was due to NaOH that was used to prepare the chlorocyclopentylsibutramine standard solution. Bisacodyl did not degrade when mixed with neutralized chlorocyclopentylsibutramine, whereas when NaOH was added, it rapidly degraded. We identified the bisacodyl degradation products using liquid chromatography-quadrupole-Orbitrap/mass spectrometry. MS2 spectra with proposed structures of fragment peaks were also obtained. CONCLUSIONS: The developed method could be used to regulate slimming products that threaten public health, and knowledge of bisacodyl degradation will be used as the basis for developing an analytic method.

Improved outcome models with denoising diffusion.

PURPOSE: Radiotherapy outcome modelling often suffers from class imbalance in the modelled endpoints. One of the main options to address this issue is by introducing new synthetically generated datapoints, using generative models, such as Denoising Diffusion Probabilistic Models (DDPM). In this study, we implemented DDPM to improve performance of a tumor local control model, trained on imbalanced dataset, and compare this approach with other common techniques. METHODS: A dataset of 535 NSCLC patients treated with SBRT (50 Gy/5 fractions) was used to train a deep learning outcome model for tumor local control prediction. The dataset included complete treatment planning data (planning CT images, 3D planning dose distribution and patient demographics) with sparsely distributed endpoints (6-7 % experiencing local failure). Consequently, we trained a novel conditional 3D DDPM model to generate synthetic treatment planning data. Synthetically generated treatment planning datapoints were used to supplement the real training dataset and the improvement in the model's performance was studied. Obtained results were also compared to other common techniques for class imbalanced training, such as Oversampling, Undersampling, Augmentation, Class Weights, SMOTE and ADASYN. RESULTS: Synthetic DDPM-generated data were visually trustworthy, with Fréchet inception distance (FID) below 50. Extending the training dataset with the synthetic data improved the model's performance by more than 10%, while other techniques exhibited only about 4% improvement. CONCLUSIONS: DDPM introduces a novel approach to class-imbalanced outcome modelling problems. The model generates realistic synthetic radiotherapy planning data, with a strong potential to increase performance and robustness of outcome models.

Efficacy of lubiprostone for functional constipation treatment in adolescents and children: Randomized controlled trial.

OBJECTIVES: Adolescent and pediatric functional constipation (FC) is a common clinical problem. Currently, data on lubiprostone for the treatment of pediatric FC are scarce. This study investigated the efficacy and safety of lubiprostone in the treatment of pediatric FC. METHODS: In a single-blinded, randomized controlled study, we included 280 patients aged 8-18 years with FC. Patients were randomized either to a weight-based lubiprostone dose (n = 140) or conventional laxatives (n = 140), including lactulose, bisacodyl, or sodium picosulfate, for 12 weeks, followed by 4 weeks posttreatment follow-up. RESULTS: Improvement in constipation was achieved in 128 (91.4%) patients in the lubiprostone group, and in 48 (34.3%) patients of the conventional therapy group (p < 0.001) and was sustained after treatment discontinuation. One quarter of the lubiprostone group experienced the first spontaneous bowel motion within 48 h after dose initiation. A total of 75.7% of the lubiprostone group could achieve and sustain Bristol stool form of 3 or 4 during the last 4 weeks of therapy and through the 4 weeks of follow-up versus 50 (35.7%) patients in the conventional therapy group (p < 0.001). No life-threatening adverse drug reactions were encountered, and no treatment-related discontinuation. Mild self-limited colicky abdominal pain and headache were the most prevalent side effects in the lubiprostone group. CONCLUSIONS: Lubiprostone is an effective and well-tolerated pharmacotherapy for youthful age and pediatric age groups, which may alter the paradigm of pediatric FC treatment.

High-resolution MRI synthesis using a data-driven framework with denoising diffusion probabilistic modeling.

Objective. High-resolution magnetic resonance imaging (MRI) can enhance lesion diagnosis, prognosis, and delineation. However, gradient power and hardware limitations prohibit recording thin slices or sub-1 mm resolution. Furthermore, long scan time is not clinically acceptable. Conventional high-resolution images generated using statistical or analytical methods include the limitation of capturing complex, high-dimensional image data with intricate patterns and structures. This study aims to harness cutting-edge diffusion probabilistic deep learning techniques to create a framework for generating high-resolution MRI from low-resolution counterparts, improving the uncertainty of denoising diffusion probabilistic models (DDPM).Approach. DDPM includes two processes. The forward process employs a Markov chain to systematically introduce Gaussian noise to low-resolution MRI images. In the reverse process, a U-Net model is trained to denoise the forward process images and produce high-resolution images conditioned on the features of their low-resolution counterparts. The proposed framework was demonstrated using T2-weighted MRI images from institutional prostate patients and brain patients collected in the Brain Tumor Segmentation Challenge 2020 (BraTS2020).Main results. For the prostate dataset, the bicubic interpolation model (Bicubic), conditional generative-adversarial network (CGAN), and our proposed DDPM framework improved the noise quality measure from low-resolution images by 4.4%, 5.7%, and 12.8%, respectively. Our method enhanced the signal-to-noise ratios by 11.7%, surpassing Bicubic (9.8%) and CGAN (8.1%). In the BraTS2020 dataset, the proposed framework and Bicubic enhanced peak signal-to-noise ratio from resolution-degraded images by 9.1% and 5.8%. The multi-scale structural similarity indexes were 0.970 ± 0.019, 0.968 ± 0.022, and 0.967 ± 0.023 for the proposed method, CGAN, and Bicubic, respectively.Significance. This study explores a deep learning-based diffusion probabilistic framework for improving MR image resolution. Such a framework can be used to improve clinical workflow by obtaining high-resolution images without penalty of the long scan time. Future investigation will likely focus on prospectively testing the efficacy of this framework with different clinical indications.

Few-shot biomedical image segmentation using diffusion models: Beyond image generation.

BACKGROUND: Medical image analysis pipelines often involve segmentation, which requires a large amount of annotated training data, which is time-consuming and costly. To address this issue, we proposed leveraging generative models to achieve few-shot image segmentation. METHODS: We trained a denoising diffusion probabilistic model (DDPM) on 480,407 pelvis radiographs to generate 256 âœ• 256 px synthetic images. The DDPM was conditioned on demographic and radiologic characteristics and was rigorously validated by domain experts and objective image quality metrics (Frechet inception distance [FID] and inception score [IS]). For the next step, three landmarks (greater trochanter [GT], lesser trochanter [LT], and obturator foramen [OF]) were annotated on 45 real-patient radiographs; 25 for training and 20 for testing. To extract features, each image was passed through the pre-trained DDPM at three timesteps and for each pass, features from specific blocks were extracted. The features were concatenated with the real image to form an image with 4225 channels. The feature-set was broken into random patches, which were fed to a U-Net. Dice Similarity Coefficient (DSC) was used to compare the performance with a vanilla U-Net trained on radiographs. RESULTS: Expert accuracy was 57.5 % in determining real versus generated images, while the model reached an FID = 7.2 and IS = 210. The segmentation UNet trained on the 20 feature-sets achieved a DSC of 0.90, 0.84, and 0.61 for OF, GT, and LT segmentation, respectively, which was at least 0.30 points higher than the naively trained model. CONCLUSION: We demonstrated the applicability of DDPMs as feature extractors, facilitating medical image segmentation with few annotated samples.

Efficacy of different bowel preparation regimen volumes for colorectal cancer screening and compliance with European Society of Gastrointestinal Endoscopy performance measures.

BACKGROUND: Various volumes of bowel preparation are used in clinical practice. There is conflicting data on the effectiveness of individual regimens. This study aims to evaluate the efficacy and compliance of currently used bowel preparations with the European Society of Gastrointestinal Endoscopy (ESGE) performance measures using data of the Dutch nationwide colorectal cancer screening (CRC) program. METHODS: In a prospective, multicenter endoscopy database, we identified all CRC screening colonoscopies performed in 15 Dutch endoscopy centers from 2016 to 2020. We excluded procedures without documented bowel preparation or the Boston Bowel Preparation Scale (BBPS) score. Bowel preparation regimens were categorized into three groups, that is, 4-L (polyethylene glycol (PEG)), 2-L (2-L PEG with ascorbic acid) and ≤1-L volumes (sodium picosulfate with magnesium citrate, 1L-PEG with sodium sulfate and ascorbic acid or oral sulfate solution). European Society of Gastrointestinal Endoscopy performance measures included adequate BBPS score (≥6) (>90%), cecal intubation rate (CIR, >90%), adenoma detection rate (ADR, >25%) and polyp detection rate (PDR, >40%). Logistic regression was performed to identify predictive factors for adequate BBPS and patient discomfort. RESULTS: A total of 39,042 CRC screening colonoscopies were included. Boston Bowel Preparation Scale scores, CIR, ADR and PDR for 4L, 2L and ≤1L regimens all met the minimum ESGE performance measures standards. However, an adequate BBPS score was more frequently seen with 2L regimens (98.0%) as compared to 4L (97.1%) and ≤1L regimens (97.0%) (p < 0.001), respectively. In addition, CIR was higher for ≤1L (98.4%) versus 4L (97.7%) and 2L (97.9%) regimens (p = 0.001), ADR higher for lower volume (≤1L (60.0%) and 2L (61.2)) versus higher volume (4L (58.6%)) regimens (p < 0.001), and PDR higher for ≤1L (70.0%) and 2L (70.8%) versus 4L (67.2%) regimens (p < 0.001). Boston Bowel Preparation Scale for ≤1L regimens was higher when combined with bisacodyl (97.3%) than without (95.6%) (p < 0.001). Overall, bisacodyl use was independently associated with higher patient discomfort (odds ratios = 1.47, confidence intervals = 1.26-1.72). CONCLUSIONS: Despite variations in bowel preparation volumes, all regimens meet the minimum ESGE performance measures for bowel preparation and other quality parameters. Boston Bowel Preparation Scale can be further improved if ultra low volume regimens are combined with bisacodyl. The choice for either bowel preparation volume can therefore be based on volume-tolerance and patient preference.

Improving Bowel Management in Children With Spina Bifida.

OBJECTIVES: In individuals with spina bifida (SB), bowel incontinence is associated with lower quality of life and lower likelihood of employment. In an effort to maximize bowel continence in children and adolescents, we created a bowel management assessment and follow-up protocol in a multidisciplinary clinic. Here we report the results of this protocol using quality-improvement methodology. METHODS: Continence was defined as no unplanned bowel movements. Our protocol involved: (1) a standardized 4-item questionnaire about bowel continence and consistency; (2) if the patient was not achieving continence, an intervention starting with oral medication (stimulant and/or osmotic laxatives), and/or suppositories (glycerin or bisacodyl) followed by an escalation to trans-anal irrigation, or continence surgery; and (3) follow-up phone calls at regular intervals to monitor progress and make changes as needed. Results are summarized with descriptive statistics. RESULTS: We screened 178 eligible patients in the SB clinic. Eighty-eight agreed to participate in the bowel management program. Of those who did not participate, the majority (68/90, 76%) were already achieving continence with their bowel regimen. Of children in the program, most (68/88, 77%) had a diagnosis of meningomyelocoele. At 1 year, the proportion of patients who were bowel accident free improved to 46% (vs 22% initially, P = 0.0007). CONCLUSIONS: A standardized bowel management protocol, primarily the use of suppositories and trans-anal irrigation to achieve social continence, as well as frequent telephone follow-up, can reduce bowel incontinence in children and adolescents with SB.

Clinical utility of colonic low-amplitude propagating contractions in children with functional constipation.

BACKGROUND: Colonic high-amplitude propagating contractions (HAPC) are generally accepted as a marker of neuromuscular integrity. Little is known about low-amplitude propagating contractions (LAPCs); we evaluated their clinical utility in children. METHODS: Retrospective review of children with functional constipation undergoing low-resolution colon manometry (CM) recording HAPCs and LAPCs (physiologic or bisacodyl-induced) in three groups: constipation, antegrade colonic enemas (ACE), and ileostomy. Outcome (therapy response) was compared to LAPCs in all patients and within groups. We evaluated LAPCs as potentially representing failed HAPCs. KEY RESULTS: A total of 445 patients were included (median age 9.0 years, 54% female), 73 had LAPCs. We found no association between LAPCs and outcome (all patients, p = 0.121), corroborated by logistic regression and excluding HAPCs. We found an association between physiologic LAPCs and outcome that disappears when excluding HAPCs or controlling with logistic regression. We found no association between outcome and bisacodyl-induced LAPCs or LAPC propagation. We found an association between LAPCs and outcome only in the constipation group that cancels with logistic regression and excluding HAPCs (p = 0.026, 0.062, and 0.243, respectively). We found a higher proportion of patients with LAPCs amongst those with absent or abnormally propagated (absent or partially propagated) HAPCs compared to those with fully propagated HAPCs (p = 0.001 and 0.004, respectively) suggesting LAPCs may represent failed HAPCs. CONCLUSIONS/INFERENCES: LAPCs do not seem to have added clinical significance in pediatric functional constipation; CM interpretation could rely primarily on the presence of HAPCs. LAPCs may represent failed HAPCs. Larger studies are needed to further validate these findings.

High amplitude propagated contractions with Glycerin versus Bisacodyl: A within-subject comparison in children undergoing colonic manometry.

BACKGROUND: The presence of high amplitude propagated contractions (HAPCs) measured by colonic manometry (CM) reflect an intact neuromuscular function of the colon. Bisacodyl and Glycerin are colonic stimulants that induce HAPCs and are used for the treatment of constipation. HAPCs characteristics with each drug have not been compared before. We aimed to compare the HAPC characteristics with Bisacodyl and Glycerin in children undergoing CM for constipation. METHODS: This is a prospective single-center cross-over study of children aged 2-18 years undergoing CM. All patients received both Glycerin and Bisacodyl during CM. They were randomized to group A with Bisacodyl first (n = 22) and group B with Glycerin first (n = 23), with 1.5 hours in between each dose. Differences in patient and HAPC characteristics between groups were summarized using descriptive statistics and compared using Chi-square test or Wilcoxon rank sum test as appropriate. KEY RESULTS: A total of 45 patients were included. HAPCs post Bisacodyl had a longer duration of action (median of 40 vs 21.5 min, p < 0.0001), longer propagation (median of 70 vs 60 cm, p = 0.02), and more HAPCs (median of 10 vs 5, p < 0.0001) compared Glycerin. No differences were found in the HAPC amplitude and onset of action between both medications.

Pre-referral rectal artesunate is no "magic bullet" in weak health systems.

Severe malaria is a potentially fatal condition that requires urgent treatment. In a clinical trial, a sub-group of children treated with rectal artesunate (RAS) before being referred to a health facility had an increased chance of survival. We recently published in BMC Medicine results of the CARAMAL Project that did not find the same protective effect of pre-referral RAS implemented at scale under real-world conditions in three African countries. Instead, CARAMAL identified serious health system shortfalls that impacted the entire continuum of care, constraining the effectiveness of RAS. Correspondence to the article criticized the observational study design and the alleged interpretation and consequences of our findings.Here, we clarify that we do not dispute the life-saving potential of RAS, and discuss the methodological criticism. We acknowledge the potential for confounding in observational studies. Nevertheless, the totality of CARAMAL evidence is in full support of our conclusion that the conditions under which RAS can be beneficial were not met in our settings, as children often failed to complete referral and post-referral treatment was inadequate.The criticism did not appear to acknowledge the realities of highly malarious settings documented in detail in the CARAMAL project. Suggesting that trial-demonstrated efficacy is sufficient to warrant large-scale deployment of pre-referral RAS ignores the paramount importance of functioning health systems for its delivery, for completing post-referral treatment, and for achieving complete cure. Presenting RAS as a "magic bullet" distracts from the most urgent priority: fixing health systems so they can provide a functioning continuum of care and save the lives of sick children.The data underlying our publication is freely accessible on Zenodo.

A sensitive and quantitative immunochromatographic assay for simultaneous detection of three stimulant laxatives in slimming food.

Bisacodyl, sodium picosulfate and their metabolite bis-(p-hydroxyphenyl)-pyridyl-2-methane (BHPM) are clinically used to treat constipation. In this study, with the rational hapten design, a broad-specific and highly sensitive monoclonal antibody (mAb) was obtained with half of inhibitory concentrations of 0.16, 0.18 and 0.65 ng/mL for bisacodyl, sodium picosulfate and BHPM, respectively. Based on this mAb, a rapid and sensitive lateral flow immunochromatographic assay toward bisacodyl, sodium picosulfate and BHPM in slimming foods was developed. This method can qualitatively and quantitatively screen three stimulant laxatives with cut-off values of 3-6 ng/mL by naked eye and quantitative detection limits of 0.14-0.41 ng/mL by reader. The acceptable recoveries of spiked samples (78.00 %-120.12 %) and consistent results with liquid chromatography with tandem mass spectrometry (LC-MS/MS) in real sample detection confirmed the accuracy of the method. The established method provides a technique for multiplex, sensitive, fast, and on-site detection of three stimulant laxatives in slimming food.

Sleep Disturbances, Bowel Movement Kinetics, and Travel Interruption With Bowel Preparation: A Bowel CLEANsing National Initiative Substudy.

INTRODUCTION: We investigated sleep disturbances, bowel movement (BM) kinetics, and travel experience with different bowel preparation regimens in a substudy of patients enrolled in a randomized multicenter Canadian clinical trial. METHODS: Patients scheduled to have a colonoscopy between 7:30 am and 10:30 am (early morning) were randomized to (i) 4-L single-dose polyethylene glycol (PEG) given in the evening before, (ii) 2-L split-dose PEG (+bisacodyl 15 mg), or (iii) 4-L split-dose PEG. Patients scheduled to undergo a colonoscopy between 10:30 am and 4:30 pm (afternoon) were randomized to (iv) 2-L single-dose PEG (+bisacodyl 15 mg) in the morning, (v) 2-L split-dose PEG (+bisacodyl 15 mg), or (vi) 4-L split-dose PEG. Patients were asked to record information on BM kinetics, sleep, and travel to the endoscopy unit. Continuous and categorical variables were compared between groups using a Kruskal-Wallis test or χ 2 test, respectively. Intention-to-treat analyses were performed. RESULTS: Overall, 641 patients were included in this substudy. Patients undergoing early morning colonoscopies reported the most awakenings in the night when assigned to 4-L single-dose day-before PEG and the highest reduction in sleep hours when assigned to 4-L split-dose PEG. There were no significant between-group differences in urgent BMs, fecal incontinence episodes, or travel interruptions. Overall, 17% of those traveling for more than an hour had to stop for a BM during travel, with no significant difference between groups. DISCUSSION: Day-before and split-dose high-volume PEG regimens for colonoscopies scheduled before 10:30 am lead to the greatest sleep disturbance.

Effect of Caffeine on Colonic Manometry in Children.

OBJECTIVES: Coffee and caffeinated products have been widely consumed for many centuries. Previous adult studies have suggested that both coffee and decaffeinated beverages induce colonic motility. However, no study has been conducted in pediatrics, and the role of caffeine alone in pediatric colonic motility needs to be explored. METHODS: A prospective study of pediatric patients undergoing standard colonic motility testing that were able to consume caffeinated coffee, decaffeinated coffee, and caffeine tablet during colonic manometry. Patients who had a gastrocolonic reflex and high amplitude propagated contractions (HAPCs) in response to intraluminal administration of bisacodyl in the colon were included in the final analyses. RESULTS: Thirty-eight patients were recruited, 22 of which were excluded, 11 due to abnormal studies (no HAPC seen in response to intraluminal response to bisacodyl), and 11 due to inability to consume all study agents or complete the study. Sixteen patients met criteria for final analyses. Intracolonic bisacodyl produced a larger area under the curve (AUC) compared to all other agents. Caffeinated coffee resulted in a higher AUC, motility index (MI), and time to HAPC compared with decaffeinated coffee ( P < 0.05). There was no significant difference between caffeinated coffee and caffeine tablet, or caffeine tablet and decaffeinated coffee. CONCLUSIONS: Caffeine is indeed a colonic stimulant; however, other components of caffeinated and non-caffeinated beverages likely induce colonic response and require further evaluation for possible use as a colonic stimulant.

Risk factors for inadequate bowel preparation in patients using high- and low-volume cleansing products.

INTRODUCTION: Bowel preparation is crucial for colonoscopy completeness and lesions detection. Today, several cleansing products are equally recommended by guidelines, irrespective of patients' characteristics. Identification of preparation-specific risk factors for inadequate bowel preparation may lead to a personalized prescription of cleansing products to refine patients' tolerance and improve endoscopic outcomes. METHODS: We prospectively enrolled consecutive outpatients referred for colonoscopy using either a high-volume [HV: 4 l polyethylene glycol (PEG)] or a low-volume (LV: 2 l PEG + bisacodyl) preparation. Day-before regimen or split-dose regimen was used for morning or afternoon colonoscopies, respectively. Univariate and multivariate analyses were conducted to identify risk factors related to inadequate bowel preparation, according to the Boston bowel preparation scale for HV and LV preparations. RESULTS: We enrolled 2040 patients, of which 1815 were included in the final analysis (average age 60.6 years, 50.2% men). Half of them (52%) used LV preparation. Adequate preparation was achieved by 87.6% without differences between the HV and LV groups (89.2% vs. 86.6%; P = 0.098). The use of day-before regimen and incomplete assumption of PEG were independent predictors of poor visibility for either HV or LV preparation. However, different specific risk factors for HV [diabetes: odds ratio (OR), 3.81; 95% confidence interval (CI), 1.91-7.58; low level of instruction: OR, 1.95; 95% CI, 1.11-3.44; and previous abdominal surgery: OR, 2.27; 95% CI, 1.20-4.30] and for LV (heart disease: OR, 2.06; 95% CI, 1.09-3.88; age > 65 years: OR, 1.51; 95% CI, 1.01-2.27) preparations were identified. CONCLUSION: Day-before preparation and incomplete assumption of the purgative agents affect bowel visibility irrespective of the preparation volume. LV should be preferred to HV preparations in patients with diabetes, low level of instruction, and previous abdominal surgery, whereas an HV preparation should be preferred in patients with heart disease and in older patients.

Effect of Bacillus coagulans SNZ 1969 on the Improvement of Bowel Movement in Loperamide-Treated SD Rats.

Bacillus coagulans SNZ 1969 (B. coagulans SNZ 1969) is a spore-forming bacterium reported to be effective in attenuating constipation. However, there is no study on whether B. coagulans SNZ 1969 could improve constipation through mucin secretion and changes in intestinal hormones. To address this knowledge gap, rats were orally administrated with various treatments for four weeks. The normal control (NOR) group received saline only. There were four constipation-induced groups. The LOP group received only loperamide (LOP), a constipation-inducing agent. The BIS group received both LOP and Bisacodyl (BIS, a constipation treatment agent). The SNZ-L group received both LOP and B. coagulans SNZ 1969 at 1 × 108 CFU/day. The SNZ-H group received LOP and B.coagulans SNZ 1969 at 1 × 1010 CFU/day. As indicators of constipation improvement, fecal pellet weight, fecal water content, gastrointestinal transit time, and intestinal motility were measured. Mucus secretion in the colon was determined by histological colon analysis and mucin-related gene expressions. Gastrointestinal (GI) hormones were also measured. SNZ-L and SNZ-H groups showed significantly increased fecal weights, fecal water contents, and intestinal motility than the LOP group. SNZ-L and SNZ-H groups also showed higher secretion of mucin in the colon and mRNA expression levels of Mucin 2 and Aquaporin 8 than the LOP group. The SNZ-H group showed significantly increased substance P but significantly decreased somatostatin and vasoactive intestinal peptide than the LOP group. The results of this study suggest that B. coagulans SNZ 1969 intake could attenuate constipation through mucin secretion and alteration of GI hormones.